Schwerpunkt Pflanzenwissenschaften am Julius-von-Sachs-Institut

Einrichtungen

Molekulare Pflanzenphysiologie und Biophysik (Botanik I)

N.N.

Bild und Link: Ökophysiologie der Pflanzen

Ökophysiologie der Pflanzen (Botanik II)

Prof. Dr. Katharina Markmann

katharina.markmann@uni-wuerzburg.de
+49 931 31-80792

Pharmazeutische Biologie

Prof. Dr. Dr. Martin J. Müller

martin.mueller@uni-wuerzburg.de
+49 931 31-86160

Kartenausschnitt des Botanischen Gartens

Botanischer Garten

Prof. Dr. Katharina Markmann

katharina.markmann@uni-wuerzburg.de
+49 931 31-80792

Veranstaltungen

Fränkisches Pflanzenforschermeeting — Fränkisches Pflanzenforschermeeting 2023

Veranstaltungskalender

Jan 23

Kolloquium des Julius-von-Sachs-Instituts
Living with fluctuations: time, scale, and reactions of crops
Marcel Quint, Martin-Luther-University Halle

Feb 06

Kolloquium des Julius-von-Sachs-Instituts
Towards an integrative global change ecology: species responses, biodiversity variation, and societal challenges
Christian Hof, JMU Würzburg

Apr 03

Girls' Day 2025 am Julius-von-Sachs-Insitut und Botanischen Garten

Nachwuchs

Nachwuchsgruppen

Dr. Kenji Fukushima
W1TTW2-Prof Dr. Nathalie Lackus

Habilitand/innen

Dr. Tobias Maierhofer
Dr. Ines Kreuzer
Dr. Kai Konrad
Shouguang Huang
Dr. Agnes Fekete
Dr. Daniel Maag
Dr. Christoph Weiste

Alumni/Nachwuchs mit Professuren

Zukunftskonzept

Zukunftskonzept des Julius-von-Sachs-Instituts

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Publikationen in Uni-weiten Kooperationen

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2023[ to top ]

Subgenome dominance shapes novel gene evolution in the decaploid pitcher plant Nepenthes gracilis. Saul, F.; Scharmann, M.; Wakatake, T.; Rajaraman, S.; Marques, A.; Freund, M.; Bringmann, G.; Channon, L.; Becker, D.; Carroll, E.; Low, Y. W.; Lindqvist, C.; Gilbert, K. J.; Renner, T.; Masuda, S.; Richter, M.; Vogg, G.; Shirasu, K.; Michael, T. P.; Hedrich, R.; Albert, V. A.; Fukushima, K. In Nat Plants. 2023.
- [ Abstract ]
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Subgenome dominance after whole-genome duplication generates distinction in gene number and expression at the level of chromosome sets, but it remains unclear how this process may be involved in evolutionary novelty. Here we generated a chromosome-scale genome assembly of the Asian pitcher plant Nepenthes gracilis to analyse how its novel traits (dioecy and carnivorous pitcher leaves) are linked to genomic evolution. We found a decaploid karyotype and a clear indication of subgenome dominance. A male-linked and pericentromerically located region on the putative sex chromosome was identified in a recessive subgenome and was found to harbour three transcription factors involved in flower and pollen development, including a likely neofunctionalized LEAFY duplicate. Transcriptomic and syntenic analyses of carnivory-related genes suggested that the paleopolyploidization events seeded genes that subsequently formed tandem clusters in recessive subgenomes with specific expression in the digestive zone of the pitcher, where specialized cells digest prey and absorb derived nutrients. A genome-scale analysis suggested that subgenome dominance likely contributed to evolutionary innovation by permitting recessive subgenomes to diversify functions of novel tissue-specific duplicates. Our results provide insight into how polyploidy can give rise to novel traits in divergent and successful high-ploidy lineages.

@article{saul2023subgenome, abstract = {Subgenome dominance after whole-genome duplication generates distinction in gene number and expression at the level of chromosome sets, but it remains unclear how this process may be involved in evolutionary novelty. Here we generated a chromosome-scale genome assembly of the Asian pitcher plant Nepenthes gracilis to analyse how its novel traits (dioecy and carnivorous pitcher leaves) are linked to genomic evolution. We found a decaploid karyotype and a clear indication of subgenome dominance. A male-linked and pericentromerically located region on the putative sex chromosome was identified in a recessive subgenome and was found to harbour three transcription factors involved in flower and pollen development, including a likely neofunctionalized LEAFY duplicate. Transcriptomic and syntenic analyses of carnivory-related genes suggested that the paleopolyploidization events seeded genes that subsequently formed tandem clusters in recessive subgenomes with specific expression in the digestive zone of the pitcher, where specialized cells digest prey and absorb derived nutrients. A genome-scale analysis suggested that subgenome dominance likely contributed to evolutionary innovation by permitting recessive subgenomes to diversify functions of novel tissue-specific duplicates. Our results provide insight into how polyploidy can give rise to novel traits in divergent and successful high-ploidy lineages.}, author = {Saul, F. and Scharmann, M. and Wakatake, T. and Rajaraman, S. and Marques, A. and Freund, M. and Bringmann, G. and Channon, L. and Becker, D. and Carroll, E. and Low, Y. W. and Lindqvist, C. and Gilbert, K. J. and Renner, T. and Masuda, S. and Richter, M. and Vogg, G. and Shirasu, K. and Michael, T. P. and Hedrich, R. and Albert, V. A. and Fukushima, K.}, journal = {Nat Plants}, keywords = {uni_network}, note = {Saul, Franziska Scharmann, Mathias Wakatake, Takanori Rajaraman, Sitaram Marques, Andre Freund, Matthias Bringmann, Gerhard Channon, Louisa Becker, Dirk Carroll, Emily Low, Yee Wen Lindqvist, Charlotte Gilbert, Kadeem J Renner, Tanya Masuda, Sachiko Richter, Michaela Vogg, Gerd Shirasu, Ken Michael, Todd P Hedrich, Rainer Albert, Victor A Fukushima, Kenji eng Sofja Kovalevskaja programme 2018/Alexander von Humboldt-Stiftung (Alexander von Humboldt Foundation)/ RGY0082/2021/Human Frontier Science Program (HFSP)/ 454506241/Deutsche Forschungsgemeinschaft (German Research Foundation)/ 699/14-2/Deutsche Forschungsgemeinschaft (German Research Foundation)/ 415282803/Deutsche Forschungsgemeinschaft (German Research Foundation)/ 2019-67012-37587/U.S. Department of Agriculture ( Department of Agriculture)/ JP20H05909/MEXT | Japan Society for the Promotion of Science (JSPS)/ 2030871/National Science Foundation (NSF)/ England 2023/11/24 Nat Plants. 2023 Nov 23. doi: 10.1038/s41477-023-01562-2.}, title = {Subgenome dominance shapes novel gene evolution in the decaploid pitcher plant Nepenthes gracilis}, type = {Journal Article}, year = 2023 }

%0 Journal Article %1 saul2023subgenome %A Saul, F. %A Scharmann, M. %A Wakatake, T. %A Rajaraman, S. %A Marques, A. %A Freund, M. %A Bringmann, G. %A Channon, L. %A Becker, D. %A Carroll, E. %A Low, Y. W. %A Lindqvist, C. %A Gilbert, K. J. %A Renner, T. %A Masuda, S. %A Richter, M. %A Vogg, G. %A Shirasu, K. %A Michael, T. P. %A Hedrich, R. %A Albert, V. A. %A Fukushima, K. %D 2023 %J Nat Plants %R 10.1038/s41477-023-01562-2 %T Subgenome dominance shapes novel gene evolution in the decaploid pitcher plant Nepenthes gracilis %U https://www.ncbi.nlm.nih.gov/pubmed/37996654https://www.nature.com/articles/s41477-023-01562-2 %X Subgenome dominance after whole-genome duplication generates distinction in gene number and expression at the level of chromosome sets, but it remains unclear how this process may be involved in evolutionary novelty. Here we generated a chromosome-scale genome assembly of the Asian pitcher plant Nepenthes gracilis to analyse how its novel traits (dioecy and carnivorous pitcher leaves) are linked to genomic evolution. We found a decaploid karyotype and a clear indication of subgenome dominance. A male-linked and pericentromerically located region on the putative sex chromosome was identified in a recessive subgenome and was found to harbour three transcription factors involved in flower and pollen development, including a likely neofunctionalized LEAFY duplicate. Transcriptomic and syntenic analyses of carnivory-related genes suggested that the paleopolyploidization events seeded genes that subsequently formed tandem clusters in recessive subgenomes with specific expression in the digestive zone of the pitcher, where specialized cells digest prey and absorb derived nutrients. A genome-scale analysis suggested that subgenome dominance likely contributed to evolutionary innovation by permitting recessive subgenomes to diversify functions of novel tissue-specific duplicates. Our results provide insight into how polyploidy can give rise to novel traits in divergent and successful high-ploidy lineages.
S₁ basic leucine zipper transcription factors shape plant architecture by controlling C/N partitioning to apical and lateral organs.. Kreisz, P.; Hellens, A.M.; Fröschel, C.; Krischke, M.; Maag, D.; Feil, R.; Wildenhain, T.; Draken, J.; Braune, G.; Erdelitsch, L.; Cecchino, L.; Wagner, T.C.; Mueller, M.J.; Becker, D.; Lunn, J.E.; Hanson, J.; Beveridge, C.A.; Fichtner, F.; Barbier, F.F.; Weiste, C. In bioRxiv, p. 2023.05.23.541964. 2023.
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Plants exhibit an immense plasticity in their architecture. While the impact of hormonal regulation is well-characterised, the importance of sugar-signalling has just recently emerged. Here, we addressed which sugar-signalling components mediate the trade-off between growth of apical versus lateral meristems and how they control organ sink-strength. Thereby, we unravelled a novel developmental function of the sugar-controlled S1 basic-leucine-zipper (S1-bZIP) transcription factors in establishing global source-sink interactions. Applying comprehensive molecular, analytical, and genetic approaches, we demonstrate that S1-bZIPs operate in a redundant manner to control tissue-specific expression of defined SWEET sugar-transporters and the GAT1_2.1 glutaminase. By these means, S1-bZIPs control carbohydrate (C)-channelling from source leaves to apical shoot and root organs and tune systemic organic nitrogen (N)-supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.Competing Interest StatementThe authors have declared no competing interest.

@article{kreisz2023ssub1sub, abstract = {Plants exhibit an immense plasticity in their architecture. While the impact of hormonal regulation is well-characterised, the importance of sugar-signalling has just recently emerged. Here, we addressed which sugar-signalling components mediate the trade-off between growth of apical versus lateral meristems and how they control organ sink-strength. Thereby, we unravelled a novel developmental function of the sugar-controlled S1 basic-leucine-zipper (S1-bZIP) transcription factors in establishing global source-sink interactions. Applying comprehensive molecular, analytical, and genetic approaches, we demonstrate that S1-bZIPs operate in a redundant manner to control tissue-specific expression of defined SWEET sugar-transporters and the GAT1_2.1 glutaminase. By these means, S1-bZIPs control carbohydrate (C)-channelling from source leaves to apical shoot and root organs and tune systemic organic nitrogen (N)-supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.Competing Interest StatementThe authors have declared no competing interest.}, author = {Kreisz, P. and Hellens, A.M. and Fröschel, C. and Krischke, M. and Maag, D. and Feil, R. and Wildenhain, T. and Draken, J. and Braune, G. and Erdelitsch, L. and Cecchino, L. and Wagner, T.C. and Mueller, M.J. and Becker, D. and Lunn, J.E. and Hanson, J. and Beveridge, C.A. and Fichtner, F. and Barbier, F.F. and Weiste, C.}, journal = {bioRxiv}, keywords = {uni_network}, pages = {2023.05.23.541964}, title = {S<sub>1</sub> basic leucine zipper transcription factors shape plant architecture by controlling C/N partitioning to apical and lateral organs}, type = {Journal Article}, year = 2023 }

%0 Journal Article %1 kreisz2023ssub1sub %A Kreisz, P. %A Hellens, A.M. %A Fröschel, C. %A Krischke, M. %A Maag, D. %A Feil, R. %A Wildenhain, T. %A Draken, J. %A Braune, G. %A Erdelitsch, L. %A Cecchino, L. %A Wagner, T.C. %A Mueller, M.J. %A Becker, D. %A Lunn, J.E. %A Hanson, J. %A Beveridge, C.A. %A Fichtner, F. %A Barbier, F.F. %A Weiste, C. %D 2023 %J bioRxiv %P 2023.05.23.541964 %R 10.1101/2023.05.23.541964 %T S<sub>1</sub> basic leucine zipper transcription factors shape plant architecture by controlling C/N partitioning to apical and lateral organs %U https://www.biorxiv.org/content/biorxiv/early/2023/05/24/2023.05.23.541964.full.pdf %X Plants exhibit an immense plasticity in their architecture. While the impact of hormonal regulation is well-characterised, the importance of sugar-signalling has just recently emerged. Here, we addressed which sugar-signalling components mediate the trade-off between growth of apical versus lateral meristems and how they control organ sink-strength. Thereby, we unravelled a novel developmental function of the sugar-controlled S1 basic-leucine-zipper (S1-bZIP) transcription factors in establishing global source-sink interactions. Applying comprehensive molecular, analytical, and genetic approaches, we demonstrate that S1-bZIPs operate in a redundant manner to control tissue-specific expression of defined SWEET sugar-transporters and the GAT1_2.1 glutaminase. By these means, S1-bZIPs control carbohydrate (C)-channelling from source leaves to apical shoot and root organs and tune systemic organic nitrogen (N)-supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.Competing Interest StatementThe authors have declared no competing interest.
DYSCALCULIA, a Venus flytrap mutant without the ability to count action potentials. Iosip, A. L.; Scherzer, S.; Bauer, S.; Becker, D.; Krischke, M.; Al-Rasheid, K. A. S.; Schultz, J.; Kreuzer, I.; Hedrich, R. In Curr Biol, 33(3), pp. 589–596 e5. 2023.
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The Venus flytrap Dionaea muscipula estimates prey nutrient content by counting trigger hair contacts initiating action potentials (APs) and calcium waves traveling all over the trap.(1)(,)(2)(,)(3) A first AP is associated with a subcritical rise in cytosolic calcium concentration, but when the second AP arrives in time, calcium levels pass the threshold required for fast trap closure. Consequently, memory function and decision-making are timed via a calcium clock.(3)(,)(4) For higher numbers of APs elicited by the struggling prey, the Ca(2+) clock connects to the networks governed by the touch hormone jasmonic acid (JA), which initiates slow, hermetic trap sealing and mining of the animal food stock.(5) Two distinct phases of trap closure can be distinguished within Dionaea's hunting cycle: (1) very fast trap snapping requiring two APs and crossing of a critical cytosolic Ca(2+) level and (2) JA-dependent slow trap sealing and prey processing induced by more than five APs. The Dionaea mutant DYSC is still able to fire touch-induced APs but does not snap close its traps and fails to enter the hunting cycle after prolonged mechanostimulation. Transcriptomic analyses revealed that upon trigger hair touch/AP stimulation, activation of calcium signaling is largely suppressed in DYSC traps. The observation that external JA application restored hunting cycle progression together with the DYSC phenotype and its transcriptional landscape indicates that DYSC cannot properly read, count, and decode touch/AP-induced calcium signals that are key in prey capture and processing.

@article{iosip2023dyscalculia, abstract = {The Venus flytrap Dionaea muscipula estimates prey nutrient content by counting trigger hair contacts initiating action potentials (APs) and calcium waves traveling all over the trap.(1)(,)(2)(,)(3) A first AP is associated with a subcritical rise in cytosolic calcium concentration, but when the second AP arrives in time, calcium levels pass the threshold required for fast trap closure. Consequently, memory function and decision-making are timed via a calcium clock.(3)(,)(4) For higher numbers of APs elicited by the struggling prey, the Ca(2+) clock connects to the networks governed by the touch hormone jasmonic acid (JA), which initiates slow, hermetic trap sealing and mining of the animal food stock.(5) Two distinct phases of trap closure can be distinguished within Dionaea's hunting cycle: (1) very fast trap snapping requiring two APs and crossing of a critical cytosolic Ca(2+) level and (2) JA-dependent slow trap sealing and prey processing induced by more than five APs. The Dionaea mutant DYSC is still able to fire touch-induced APs but does not snap close its traps and fails to enter the hunting cycle after prolonged mechanostimulation. Transcriptomic analyses revealed that upon trigger hair touch/AP stimulation, activation of calcium signaling is largely suppressed in DYSC traps. The observation that external JA application restored hunting cycle progression together with the DYSC phenotype and its transcriptional landscape indicates that DYSC cannot properly read, count, and decode touch/AP-induced calcium signals that are key in prey capture and processing.}, author = {Iosip, A. L. and Scherzer, S. and Bauer, S. and Becker, D. and Krischke, M. and Al-Rasheid, K. A. S. and Schultz, J. and Kreuzer, I. and Hedrich, R.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Iosip, Anda-Larisa Scherzer, Sonke Bauer, Sonja Becker, Dirk Krischke, Markus Al-Rasheid, Khaled A S Schultz, Jorg Kreuzer, Ines Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2023/01/25 Curr Biol. 2023 Feb 6;33(3):589-596.e5. doi: 10.1016/j.cub.2022.12.058. Epub 2023 Jan 23.}, number = 3, pages = {589-596 e5}, title = {DYSCALCULIA, a Venus flytrap mutant without the ability to count action potentials}, type = {Journal Article}, volume = 33, year = 2023 }

%0 Journal Article %1 iosip2023dyscalculia %A Iosip, A. L. %A Scherzer, S. %A Bauer, S. %A Becker, D. %A Krischke, M. %A Al-Rasheid, K. A. S. %A Schultz, J. %A Kreuzer, I. %A Hedrich, R. %D 2023 %J Curr Biol %N 3 %P 589-596 e5 %R 10.1016/j.cub.2022.12.058 %T DYSCALCULIA, a Venus flytrap mutant without the ability to count action potentials %U https://www.ncbi.nlm.nih.gov/pubmed/36693369 %V 33 %X The Venus flytrap Dionaea muscipula estimates prey nutrient content by counting trigger hair contacts initiating action potentials (APs) and calcium waves traveling all over the trap.(1)(,)(2)(,)(3) A first AP is associated with a subcritical rise in cytosolic calcium concentration, but when the second AP arrives in time, calcium levels pass the threshold required for fast trap closure. Consequently, memory function and decision-making are timed via a calcium clock.(3)(,)(4) For higher numbers of APs elicited by the struggling prey, the Ca(2+) clock connects to the networks governed by the touch hormone jasmonic acid (JA), which initiates slow, hermetic trap sealing and mining of the animal food stock.(5) Two distinct phases of trap closure can be distinguished within Dionaea's hunting cycle: (1) very fast trap snapping requiring two APs and crossing of a critical cytosolic Ca(2+) level and (2) JA-dependent slow trap sealing and prey processing induced by more than five APs. The Dionaea mutant DYSC is still able to fire touch-induced APs but does not snap close its traps and fails to enter the hunting cycle after prolonged mechanostimulation. Transcriptomic analyses revealed that upon trigger hair touch/AP stimulation, activation of calcium signaling is largely suppressed in DYSC traps. The observation that external JA application restored hunting cycle progression together with the DYSC phenotype and its transcriptional landscape indicates that DYSC cannot properly read, count, and decode touch/AP-induced calcium signals that are key in prey capture and processing.
Ambient and substrate energy influence decomposer diversity differentially across trophic levels. Kriegel, P.; Vogel, S.; Angeleri, R.; Baldrian, P.; Borken, W.; Bouget, C.; Brin, A.; Bussler, H.; Cocciufa, C.; Feldmann, B.; Gossner, M. M.; Haeler, E.; Hagge, J.; Hardersen, S.; Hartmann, H.; Hjalten, J.; Kotowska, M. M.; Lachat, T.; Larrieu, L.; Leverkus, A. B.; Macagno, A. L. M.; Mitesser, O.; Muller, J.; Obermaier, E.; Parisi, F.; Pelz, S.; Schuldt, B.; Seibold, S.; Stengel, E.; Sverdrup-Thygeson, A.; Weisser, W.; Thorn, S. In Ecol Lett, 26(7), pp. 1157–1173. 2023.
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The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non-structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood-inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host-phylogeny-controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non-structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species-energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy.

@article{kriegel2023ambient, abstract = {The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non-structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood-inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host-phylogeny-controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non-structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species-energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy.}, author = {Kriegel, P. and Vogel, S. and Angeleri, R. and Baldrian, P. and Borken, W. and Bouget, C. and Brin, A. and Bussler, H. and Cocciufa, C. and Feldmann, B. and Gossner, M. M. and Haeler, E. and Hagge, J. and Hardersen, S. and Hartmann, H. and Hjalten, J. and Kotowska, M. M. and Lachat, T. and Larrieu, L. and Leverkus, A. B. and Macagno, A. L. M. and Mitesser, O. and Muller, J. and Obermaier, E. and Parisi, F. and Pelz, S. and Schuldt, B. and Seibold, S. and Stengel, E. and Sverdrup-Thygeson, A. and Weisser, W. and Thorn, S.}, journal = {Ecol Lett}, keywords = {uni_network}, note = {Kriegel, Peter Vogel, Sebastian Angeleri, Romain Baldrian, Petr Borken, Werner Bouget, Christophe Brin, Antoine Bussler, Heinz Cocciufa, Cristiana Feldmann, Benedikt Gossner, Martin M Haeler, Elena Hagge, Jonas Hardersen, Sonke Hartmann, Henrik Hjalten, Joakim Kotowska, Martyna M Lachat, Thibault Larrieu, Laurent Leverkus, Alexandro B Macagno, Anna L M Mitesser, Oliver Muller, Jorg Obermaier, Elisabeth Parisi, Francesco Pelz, Stefan Schuldt, Bernhard Seibold, Sebastian Stengel, Elisa Sverdrup-Thygeson, Anne Weisser, Wolfgang Thorn, Simon eng Bauer-und Stemmler Stiftung/ 22-27166S/Czech Science Foundation/ 20016/466/Deutsche Bundesstiftung Umwelt/ TH 2218/5-1/Deutsche Forschungsgemeinschaft/ Letter England 2023/05/09 Ecol Lett. 2023 Jul;26(7):1157-1173. doi: 10.1111/ele.14227. Epub 2023 May 8.}, number = 7, pages = {1157-1173}, title = {Ambient and substrate energy influence decomposer diversity differentially across trophic levels}, type = {Journal Article}, volume = 26, year = 2023 }

%0 Journal Article %1 kriegel2023ambient %A Kriegel, P. %A Vogel, S. %A Angeleri, R. %A Baldrian, P. %A Borken, W. %A Bouget, C. %A Brin, A. %A Bussler, H. %A Cocciufa, C. %A Feldmann, B. %A Gossner, M. M. %A Haeler, E. %A Hagge, J. %A Hardersen, S. %A Hartmann, H. %A Hjalten, J. %A Kotowska, M. M. %A Lachat, T. %A Larrieu, L. %A Leverkus, A. B. %A Macagno, A. L. M. %A Mitesser, O. %A Muller, J. %A Obermaier, E. %A Parisi, F. %A Pelz, S. %A Schuldt, B. %A Seibold, S. %A Stengel, E. %A Sverdrup-Thygeson, A. %A Weisser, W. %A Thorn, S. %D 2023 %J Ecol Lett %N 7 %P 1157-1173 %R 10.1111/ele.14227 %T Ambient and substrate energy influence decomposer diversity differentially across trophic levels %U https://www.ncbi.nlm.nih.gov/pubmed/37156097 %V 26 %X The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non-structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood-inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host-phylogeny-controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non-structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species-energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy.
Tobacco leaf tissue rapidly detoxifies direct salt loads without activation of calcium and SOS signaling. Graus, D.; Li, K.; Rathje, J. M.; Ding, M.; Krischke, M.; Muller, M. J.; Cuin, T. A.; Al-Rasheid, K. A. S.; Scherzer, S.; Marten, I.; Konrad, K. R.; Hedrich, R. In New Phytol, 237(1), pp. 217–231. 2023.
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Salt stress is a major abiotic stress, responsible for declining agricultural productivity. Roots are regarded as hubs for salt detoxification, however, leaf salt concentrations may exceed those of roots. How mature leaves manage acute sodium chloride (NaCl) stress is mostly unknown. To analyze the mechanisms for NaCl redistribution in leaves, salt was infiltrated into intact tobacco leaves. It initiated pronounced osmotically-driven leaf movements. Leaf downward movement caused by hydro-passive turgor loss reached a maximum within 2 h. Salt-driven cellular water release was accompanied by a transient change in membrane depolarization but not an increase in cytosolic calcium ion (Ca(2+) ) level. Nonetheless, only half an hour later, the leaves had completely regained turgor. This recovery phase was characterized by an increase in mesophyll cell plasma membrane hydrogen ion (H(+) ) pumping, a salt uptake-dependent cytosolic alkalization, and a return of the apoplast osmolality to pre-stress levels. Although, transcript numbers of abscisic acid- and Salt Overly Sensitive pathway elements remained unchanged, salt adaptation depended on the vacuolar H(+) /Na(+) -exchanger NHX1. Altogether, tobacco leaves can detoxify sodium ions (Na(+) ) rapidly even under massive salt loads, based on pre-established posttranslational settings and NHX1 cation/H(+) antiport activity. Unlike roots, signaling and processing of salt stress in tobacco leaves does not depend on Ca(2+) signaling.

@article{graus2023tobacco, abstract = {Salt stress is a major abiotic stress, responsible for declining agricultural productivity. Roots are regarded as hubs for salt detoxification, however, leaf salt concentrations may exceed those of roots. How mature leaves manage acute sodium chloride (NaCl) stress is mostly unknown. To analyze the mechanisms for NaCl redistribution in leaves, salt was infiltrated into intact tobacco leaves. It initiated pronounced osmotically-driven leaf movements. Leaf downward movement caused by hydro-passive turgor loss reached a maximum within 2 h. Salt-driven cellular water release was accompanied by a transient change in membrane depolarization but not an increase in cytosolic calcium ion (Ca(2+) ) level. Nonetheless, only half an hour later, the leaves had completely regained turgor. This recovery phase was characterized by an increase in mesophyll cell plasma membrane hydrogen ion (H(+) ) pumping, a salt uptake-dependent cytosolic alkalization, and a return of the apoplast osmolality to pre-stress levels. Although, transcript numbers of abscisic acid- and Salt Overly Sensitive pathway elements remained unchanged, salt adaptation depended on the vacuolar H(+) /Na(+) -exchanger NHX1. Altogether, tobacco leaves can detoxify sodium ions (Na(+) ) rapidly even under massive salt loads, based on pre-established posttranslational settings and NHX1 cation/H(+) antiport activity. Unlike roots, signaling and processing of salt stress in tobacco leaves does not depend on Ca(2+) signaling.}, author = {Graus, D. and Li, K. and Rathje, J. M. and Ding, M. and Krischke, M. and Muller, M. J. and Cuin, T. A. and Al-Rasheid, K. A. S. and Scherzer, S. and Marten, I. and Konrad, K. R. and Hedrich, R.}, journal = {New Phytol}, keywords = {uni_network}, note = {Graus, Dorothea Li, Kunkun Rathje, Jan M Ding, Meiqi Krischke, Markus Muller, Martin J Cuin, Tracey Ann Al-Rasheid, Khaled A S Scherzer, Sonke Marten, Irene Konrad, Kai R Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2022/09/22 New Phytol. 2023 Jan;237(1):217-231. doi: 10.1111/nph.18501. Epub 2022 Oct 14.}, number = 1, pages = {217-231}, title = {Tobacco leaf tissue rapidly detoxifies direct salt loads without activation of calcium and SOS signaling}, type = {Journal Article}, volume = 237, year = 2023 }

%0 Journal Article %1 graus2023tobacco %A Graus, D. %A Li, K. %A Rathje, J. M. %A Ding, M. %A Krischke, M. %A Muller, M. J. %A Cuin, T. A. %A Al-Rasheid, K. A. S. %A Scherzer, S. %A Marten, I. %A Konrad, K. R. %A Hedrich, R. %D 2023 %J New Phytol %N 1 %P 217-231 %R 10.1111/nph.18501 %T Tobacco leaf tissue rapidly detoxifies direct salt loads without activation of calcium and SOS signaling %U https://www.ncbi.nlm.nih.gov/pubmed/36128659 %V 237 %X Salt stress is a major abiotic stress, responsible for declining agricultural productivity. Roots are regarded as hubs for salt detoxification, however, leaf salt concentrations may exceed those of roots. How mature leaves manage acute sodium chloride (NaCl) stress is mostly unknown. To analyze the mechanisms for NaCl redistribution in leaves, salt was infiltrated into intact tobacco leaves. It initiated pronounced osmotically-driven leaf movements. Leaf downward movement caused by hydro-passive turgor loss reached a maximum within 2 h. Salt-driven cellular water release was accompanied by a transient change in membrane depolarization but not an increase in cytosolic calcium ion (Ca(2+) ) level. Nonetheless, only half an hour later, the leaves had completely regained turgor. This recovery phase was characterized by an increase in mesophyll cell plasma membrane hydrogen ion (H(+) ) pumping, a salt uptake-dependent cytosolic alkalization, and a return of the apoplast osmolality to pre-stress levels. Although, transcript numbers of abscisic acid- and Salt Overly Sensitive pathway elements remained unchanged, salt adaptation depended on the vacuolar H(+) /Na(+) -exchanger NHX1. Altogether, tobacco leaves can detoxify sodium ions (Na(+) ) rapidly even under massive salt loads, based on pre-established posttranslational settings and NHX1 cation/H(+) antiport activity. Unlike roots, signaling and processing of salt stress in tobacco leaves does not depend on Ca(2+) signaling.
Vicia faba SV channel VfTPC1 is a hyperexcitable variant of plant vacuole Two Pore Channels. Lu, J.; Dreyer, I.; Dickinson, M. S.; Panzer, S.; Jaslan, D.; Navarro-Retamal, C.; Geiger, D.; Terpitz, U.; Becker, D.; Stroud, R. M.; Marten, I.; Hedrich, R. In Elife, 12. 2023.
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To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca(2+). In our search for species-dependent functional TPC1 channel variants with different luminal Ca(2+) sensitivity, we found in total three acidic residues present in Ca(2+) sensor sites 2 and 3 of the Ca(2+)-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca(2+). When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca(2+) sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca(2+) sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche.

@article{lu2023vicia, abstract = {To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca(2+). In our search for species-dependent functional TPC1 channel variants with different luminal Ca(2+) sensitivity, we found in total three acidic residues present in Ca(2+) sensor sites 2 and 3 of the Ca(2+)-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca(2+). When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca(2+) sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca(2+) sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche.}, author = {Lu, J. and Dreyer, I. and Dickinson, M. S. and Panzer, S. and Jaslan, D. and Navarro-Retamal, C. and Geiger, D. and Terpitz, U. and Becker, D. and Stroud, R. M. and Marten, I. and Hedrich, R.}, journal = {Elife}, keywords = {uni_network}, note = {Lu, Jinping Dreyer, Ingo Dickinson, Miles Sasha Panzer, Sabine Jaslan, Dawid Navarro-Retamal, Carlos Geiger, Dietmar Terpitz, Ulrich Becker, Dirk Stroud, Robert M Marten, Irene Hedrich, Rainer eng Koselleck award HE 1640/42-1/Deutsche Forschungsgemeinschaft/ priority programs 'MAdLand - Molecular Adaptation to Land: Plant Evolution to Change' HE 1640/45-1/Deutsche Forschungsgemeinschaft/ priority programs 'MAdLand - Molecular Adaptation to Land: Plant Evolution to Change' BE1867/9-1/Deutsche Forschungsgemeinschaft/ doctoral fellowship/China Scholarship Council/ STIPET fellowship/Deutscher Akademischer Austauschdienst/ FONDEQUIP EQM160063/Comision Nacional de Investigacion Cientifica y Tecnologica/ ATE220043/Anilio-Anid/ 3170434/Fondo Nacional de Desarrollo Cientifico y Tecnologico/ 1220504/Fondo Nacional de Desarrollo Cientifico y Tecnologico/ England 2023/11/22 Elife. 2023 Nov 22;12:e86384. doi: 10.7554/eLife.86384.}, title = {Vicia faba SV channel VfTPC1 is a hyperexcitable variant of plant vacuole Two Pore Channels}, type = {Journal Article}, volume = 12, year = 2023 }

%0 Journal Article %1 lu2023vicia %A Lu, J. %A Dreyer, I. %A Dickinson, M. S. %A Panzer, S. %A Jaslan, D. %A Navarro-Retamal, C. %A Geiger, D. %A Terpitz, U. %A Becker, D. %A Stroud, R. M. %A Marten, I. %A Hedrich, R. %D 2023 %J Elife %R 10.7554/eLife.86384 %T Vicia faba SV channel VfTPC1 is a hyperexcitable variant of plant vacuole Two Pore Channels %U https://www.ncbi.nlm.nih.gov/pubmed/37991833https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10665017/pdf/elife-86384.pdf %V 12 %X To fire action-potential-like electrical signals, the vacuole membrane requires the two-pore channel TPC1, formerly called SV channel. The TPC1/SV channel functions as a depolarization-stimulated, non-selective cation channel that is inhibited by luminal Ca(2+). In our search for species-dependent functional TPC1 channel variants with different luminal Ca(2+) sensitivity, we found in total three acidic residues present in Ca(2+) sensor sites 2 and 3 of the Ca(2+)-sensitive AtTPC1 channel from Arabidopsis thaliana that were neutral in its Vicia faba ortholog and also in those of many other Fabaceae. When expressed in the Arabidopsis AtTPC1-loss-of-function background, wild-type VfTPC1 was hypersensitive to vacuole depolarization and only weakly sensitive to blocking luminal Ca(2+). When AtTPC1 was mutated for these VfTPC1-homologous polymorphic residues, two neutral substitutions in Ca(2+) sensor site 3 alone were already sufficient for the Arabidopsis At-VfTPC1 channel mutant to gain VfTPC1-like voltage and luminal Ca(2+) sensitivity that together rendered vacuoles hyperexcitable. Thus, natural TPC1 channel variants exist in plant families which may fine-tune vacuole excitability and adapt it to environmental settings of the particular ecological niche.
Carnivory on demand: phosphorus deficiency induces glandular leaves in the African liana Triphyophyllum peltatum. Winkelmann, T.; Bringmann, G.; Herwig, A.; Hedrich, R. In New Phytol, 239(3), pp. 1140–1152. 2023.
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Triphyophyllum peltatum, a rare tropical African liana, is unique in its facultative carnivory. The trigger for carnivory is yet unknown, mainly because the plant is difficult to propagate and cultivate. This study aimed at identifying the conditions that result in the formation of carnivorous leaves. In vitro shoots were subjected to abiotic stressors in general and deficiencies of the major nutrients nitrogen, potassium and phosphorus in particular, to trigger carnivorous leaves' development. Adventitious root formation was improved to allow verification of the trigger in glasshouse-grown plants. Among all the stressors tested, only under phosphorus deficiency, the formation of carnivorous leaves was observed. These glandular leaves fully resembled those found under natural growing conditions including the secretion of sticky liquid by mature capture organs. To generate plants for glasshouse experiments, a pulse of 55.4 muM alpha-naphthaleneacetic acid was essential to achieve 90% in vitro rooting. This plant material facilitated the confirmation of phosphorus starvation to be essential and sufficient for carnivory induction, also under ex vitro conditions. Having established the cultivation of T. peltatum and the induction of carnivory, future gene expression profiles from phosphorus starvation-induced leaves will provide important insight to the molecular mechanism of carnivory on demand.

@article{winkelmann2023carnivory, abstract = {Triphyophyllum peltatum, a rare tropical African liana, is unique in its facultative carnivory. The trigger for carnivory is yet unknown, mainly because the plant is difficult to propagate and cultivate. This study aimed at identifying the conditions that result in the formation of carnivorous leaves. In vitro shoots were subjected to abiotic stressors in general and deficiencies of the major nutrients nitrogen, potassium and phosphorus in particular, to trigger carnivorous leaves' development. Adventitious root formation was improved to allow verification of the trigger in glasshouse-grown plants. Among all the stressors tested, only under phosphorus deficiency, the formation of carnivorous leaves was observed. These glandular leaves fully resembled those found under natural growing conditions including the secretion of sticky liquid by mature capture organs. To generate plants for glasshouse experiments, a pulse of 55.4 muM alpha-naphthaleneacetic acid was essential to achieve 90% in vitro rooting. This plant material facilitated the confirmation of phosphorus starvation to be essential and sufficient for carnivory induction, also under ex vitro conditions. Having established the cultivation of T. peltatum and the induction of carnivory, future gene expression profiles from phosphorus starvation-induced leaves will provide important insight to the molecular mechanism of carnivory on demand.}, author = {Winkelmann, T. and Bringmann, G. and Herwig, A. and Hedrich, R.}, journal = {New Phytol}, keywords = {*Phosphorus}, note = {Winkelmann, Traud Bringmann, Gerhard Herwig, Anne Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2023/05/16 New Phytol. 2023 Aug;239(3):1140-1152. doi: 10.1111/nph.18960. Epub 2023 May 16.}, number = 3, pages = {1140-1152}, title = {Carnivory on demand: phosphorus deficiency induces glandular leaves in the African liana Triphyophyllum peltatum}, type = {Journal Article}, volume = 239, year = 2023 }

%0 Journal Article %1 winkelmann2023carnivory %A Winkelmann, T. %A Bringmann, G. %A Herwig, A. %A Hedrich, R. %D 2023 %J New Phytol %N 3 %P 1140-1152 %R 10.1111/nph.18960 %T Carnivory on demand: phosphorus deficiency induces glandular leaves in the African liana Triphyophyllum peltatum %U https://www.ncbi.nlm.nih.gov/pubmed/37191044 %V 239 %X Triphyophyllum peltatum, a rare tropical African liana, is unique in its facultative carnivory. The trigger for carnivory is yet unknown, mainly because the plant is difficult to propagate and cultivate. This study aimed at identifying the conditions that result in the formation of carnivorous leaves. In vitro shoots were subjected to abiotic stressors in general and deficiencies of the major nutrients nitrogen, potassium and phosphorus in particular, to trigger carnivorous leaves' development. Adventitious root formation was improved to allow verification of the trigger in glasshouse-grown plants. Among all the stressors tested, only under phosphorus deficiency, the formation of carnivorous leaves was observed. These glandular leaves fully resembled those found under natural growing conditions including the secretion of sticky liquid by mature capture organs. To generate plants for glasshouse experiments, a pulse of 55.4 muM alpha-naphthaleneacetic acid was essential to achieve 90% in vitro rooting. This plant material facilitated the confirmation of phosphorus starvation to be essential and sufficient for carnivory induction, also under ex vitro conditions. Having established the cultivation of T. peltatum and the induction of carnivory, future gene expression profiles from phosphorus starvation-induced leaves will provide important insight to the molecular mechanism of carnivory on demand.
Central Role of Sibling Small RNAs NgncR_162 and NgncR_163 in Main Metabolic Pathways of Neisseria gonorrhoeae. Steiner, T.; Zachary, M.; Bauer, S.; Muller, M. J.; Krischke, M.; Radziej, S.; Klepsch, M.; Huettel, B.; Eisenreich, W.; Rudel, T.; Beier, D. In mBio, 14(1), p. e0309322. 2023.
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Small bacterial regulatory RNAs (sRNAs) have been implicated in the regulation of numerous metabolic pathways. In most of these studies, sRNA-dependent regulation of mRNAs or proteins of enzymes in metabolic pathways has been predicted to affect the metabolism of these bacteria. However, only in a very few cases has the role in metabolism been demonstrated. Here, we performed a combined transcriptome and metabolome analysis to define the regulon of the sibling sRNAs NgncR_162 and NgncR_163 (NgncR_162/163) and their impact on the metabolism of Neisseria gonorrhoeae. These sRNAs have been reported to control genes of the citric acid and methylcitric acid cycles by posttranscriptional negative regulation. By transcriptome analysis, we now expand the NgncR_162/163 regulon by several new members and provide evidence that the sibling sRNAs act as both negative and positive regulators of target gene expression. Newly identified NgncR_162/163 targets are mostly involved in transport processes, especially in the uptake of glycine, phenylalanine, and branched-chain amino acids. NgncR_162/163 also play key roles in the control of serine-glycine metabolism and, hence, probably affect biosyntheses of nucleotides, vitamins, and other amino acids via the supply of one-carbon (C(1)) units. Indeed, these roles were confirmed by metabolomics and metabolic flux analysis, which revealed a bipartite metabolic network with glucose degradation for the supply of anabolic pathways and the usage of amino acids via the citric acid cycle for energy metabolism. Thus, by combined deep RNA sequencing (RNA-seq) and metabolomics, we significantly extended the regulon of NgncR_162/163 and demonstrated the role of NgncR_162/163 in the regulation of central metabolic pathways of the gonococcus. IMPORTANCE Neisseria gonorrhoeae is a major human pathogen which infects more than 100 million people every year. An alarming development is the emergence of gonococcal strains that are resistant against virtually all antibiotics used for their treatment. Despite the medical importance and the vanishing treatment options of gonococcal infections, the bacterial metabolism and its regulation have been only weakly defined until today. Using RNA-seq, metabolomics, and (13)C-guided metabolic flux analysis, we here investigated the gonococcal metabolism and its regulation by the previously studied sibling sRNAs NgncR_162/163. The results demonstrate the regulation of transport processes and metabolic pathways involved in the biosynthesis of nucleotides, vitamins, and amino acids by NgncR_162/163. In particular, the combination of transcriptome and metabolic flux analyses provides a heretofore unreached depth of understanding the core metabolic pathways and their regulation by the neisserial sibling sRNAs. This integrative approach may therefore also be suitable for the functional analysis of a growing number of other bacterial metabolic sRNA regulators.

@article{steiner2023central, abstract = {Small bacterial regulatory RNAs (sRNAs) have been implicated in the regulation of numerous metabolic pathways. In most of these studies, sRNA-dependent regulation of mRNAs or proteins of enzymes in metabolic pathways has been predicted to affect the metabolism of these bacteria. However, only in a very few cases has the role in metabolism been demonstrated. Here, we performed a combined transcriptome and metabolome analysis to define the regulon of the sibling sRNAs NgncR_162 and NgncR_163 (NgncR_162/163) and their impact on the metabolism of Neisseria gonorrhoeae. These sRNAs have been reported to control genes of the citric acid and methylcitric acid cycles by posttranscriptional negative regulation. By transcriptome analysis, we now expand the NgncR_162/163 regulon by several new members and provide evidence that the sibling sRNAs act as both negative and positive regulators of target gene expression. Newly identified NgncR_162/163 targets are mostly involved in transport processes, especially in the uptake of glycine, phenylalanine, and branched-chain amino acids. NgncR_162/163 also play key roles in the control of serine-glycine metabolism and, hence, probably affect biosyntheses of nucleotides, vitamins, and other amino acids via the supply of one-carbon (C(1)) units. Indeed, these roles were confirmed by metabolomics and metabolic flux analysis, which revealed a bipartite metabolic network with glucose degradation for the supply of anabolic pathways and the usage of amino acids via the citric acid cycle for energy metabolism. Thus, by combined deep RNA sequencing (RNA-seq) and metabolomics, we significantly extended the regulon of NgncR_162/163 and demonstrated the role of NgncR_162/163 in the regulation of central metabolic pathways of the gonococcus. IMPORTANCE Neisseria gonorrhoeae is a major human pathogen which infects more than 100 million people every year. An alarming development is the emergence of gonococcal strains that are resistant against virtually all antibiotics used for their treatment. Despite the medical importance and the vanishing treatment options of gonococcal infections, the bacterial metabolism and its regulation have been only weakly defined until today. Using RNA-seq, metabolomics, and (13)C-guided metabolic flux analysis, we here investigated the gonococcal metabolism and its regulation by the previously studied sibling sRNAs NgncR_162/163. The results demonstrate the regulation of transport processes and metabolic pathways involved in the biosynthesis of nucleotides, vitamins, and amino acids by NgncR_162/163. In particular, the combination of transcriptome and metabolic flux analyses provides a heretofore unreached depth of understanding the core metabolic pathways and their regulation by the neisserial sibling sRNAs. This integrative approach may therefore also be suitable for the functional analysis of a growing number of other bacterial metabolic sRNA regulators.}, author = {Steiner, T. and Zachary, M. and Bauer, S. and Muller, M. J. and Krischke, M. and Radziej, S. and Klepsch, M. and Huettel, B. and Eisenreich, W. and Rudel, T. and Beier, D.}, journal = {mBio}, keywords = {uni_network}, note = {Steiner, Thomas Zachary, Marie Bauer, Susanne Muller, Martin J Krischke, Markus Radziej, Sandra Klepsch, Maximilian Huettel, Bruno Eisenreich, Wolfgang Rudel, Thomas Beier, Dagmar eng Research Support, Non-U.S. Gov't 2023/01/05 mBio. 2023 Feb 28;14(1):e0309322. doi: 10.1128/mbio.03093-22. Epub 2023 Jan 4.}, number = 1, pages = {e0309322}, title = {Central Role of Sibling Small RNAs NgncR_162 and NgncR_163 in Main Metabolic Pathways of Neisseria gonorrhoeae}, type = {Journal Article}, volume = 14, year = 2023 }

%0 Journal Article %1 steiner2023central %A Steiner, T. %A Zachary, M. %A Bauer, S. %A Muller, M. J. %A Krischke, M. %A Radziej, S. %A Klepsch, M. %A Huettel, B. %A Eisenreich, W. %A Rudel, T. %A Beier, D. %D 2023 %J mBio %N 1 %P e0309322 %R 10.1128/mbio.03093-22 %T Central Role of Sibling Small RNAs NgncR_162 and NgncR_163 in Main Metabolic Pathways of Neisseria gonorrhoeae %U https://www.ncbi.nlm.nih.gov/pubmed/36598194https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9973317/pdf/mbio.03093-22.pdf %V 14 %X Small bacterial regulatory RNAs (sRNAs) have been implicated in the regulation of numerous metabolic pathways. In most of these studies, sRNA-dependent regulation of mRNAs or proteins of enzymes in metabolic pathways has been predicted to affect the metabolism of these bacteria. However, only in a very few cases has the role in metabolism been demonstrated. Here, we performed a combined transcriptome and metabolome analysis to define the regulon of the sibling sRNAs NgncR_162 and NgncR_163 (NgncR_162/163) and their impact on the metabolism of Neisseria gonorrhoeae. These sRNAs have been reported to control genes of the citric acid and methylcitric acid cycles by posttranscriptional negative regulation. By transcriptome analysis, we now expand the NgncR_162/163 regulon by several new members and provide evidence that the sibling sRNAs act as both negative and positive regulators of target gene expression. Newly identified NgncR_162/163 targets are mostly involved in transport processes, especially in the uptake of glycine, phenylalanine, and branched-chain amino acids. NgncR_162/163 also play key roles in the control of serine-glycine metabolism and, hence, probably affect biosyntheses of nucleotides, vitamins, and other amino acids via the supply of one-carbon (C(1)) units. Indeed, these roles were confirmed by metabolomics and metabolic flux analysis, which revealed a bipartite metabolic network with glucose degradation for the supply of anabolic pathways and the usage of amino acids via the citric acid cycle for energy metabolism. Thus, by combined deep RNA sequencing (RNA-seq) and metabolomics, we significantly extended the regulon of NgncR_162/163 and demonstrated the role of NgncR_162/163 in the regulation of central metabolic pathways of the gonococcus. IMPORTANCE Neisseria gonorrhoeae is a major human pathogen which infects more than 100 million people every year. An alarming development is the emergence of gonococcal strains that are resistant against virtually all antibiotics used for their treatment. Despite the medical importance and the vanishing treatment options of gonococcal infections, the bacterial metabolism and its regulation have been only weakly defined until today. Using RNA-seq, metabolomics, and (13)C-guided metabolic flux analysis, we here investigated the gonococcal metabolism and its regulation by the previously studied sibling sRNAs NgncR_162/163. The results demonstrate the regulation of transport processes and metabolic pathways involved in the biosynthesis of nucleotides, vitamins, and amino acids by NgncR_162/163. In particular, the combination of transcriptome and metabolic flux analyses provides a heretofore unreached depth of understanding the core metabolic pathways and their regulation by the neisserial sibling sRNAs. This integrative approach may therefore also be suitable for the functional analysis of a growing number of other bacterial metabolic sRNA regulators.
Addressing controversies in the xylem embolism resistance-vessel diameter relationship. Isasa, E.; Link, R. M.; Jansen, S.; Tezeh, F. R.; Kaack, L.; Sarmento Cabral, J.; Schuldt, B. In New Phytol, 238(1), pp. 283–296. 2023.
- [ Abstract ]
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Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones. We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P(50) ) with hydraulically weighted vessel diameter (D(h) ) and tested its link to pit membrane thickness (T(PM) ) and specific conductivity (K(s) ) on species level. Embolism-resistant species had thick pit membranes and narrow vessels. While D(h) was weakly associated with T(PM) , the P(50) -D(h) relationship remained highly significant after accounting for T(PM) . The interspecific pattern between P(50) and D(h) was mirrored by a link between P(50) and K(s) , but there was no evidence for an intraspecific relationship. Our results provide robust evidence for an interspecific P(50) -D(h) relationship across our species. As a potential cause for the inconsistencies in published P(50) -D(h) relationships, our analysis suggests differences in the range of trait values covered, and the level of data aggregation (species, tree or sample level) studied.

@article{isasa2023addressing, abstract = {Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones. We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P(50) ) with hydraulically weighted vessel diameter (D(h) ) and tested its link to pit membrane thickness (T(PM) ) and specific conductivity (K(s) ) on species level. Embolism-resistant species had thick pit membranes and narrow vessels. While D(h) was weakly associated with T(PM) , the P(50) -D(h) relationship remained highly significant after accounting for T(PM) . The interspecific pattern between P(50) and D(h) was mirrored by a link between P(50) and K(s) , but there was no evidence for an intraspecific relationship. Our results provide robust evidence for an interspecific P(50) -D(h) relationship across our species. As a potential cause for the inconsistencies in published P(50) -D(h) relationships, our analysis suggests differences in the range of trait values covered, and the level of data aggregation (species, tree or sample level) studied.}, author = {Isasa, E. and Link, R. M. and Jansen, S. and Tezeh, F. R. and Kaack, L. and Sarmento Cabral, J. and Schuldt, B.}, journal = {New Phytol}, keywords = {uni_network}, note = {Isasa, Emilie Link, Roman Mathias Jansen, Steven Tezeh, Fon Robinson Kaack, Lucian Sarmento Cabral, Juliano Schuldt, Bernhard eng Research Support, Non-U.S. Gov't England 2023/01/14 New Phytol. 2023 Apr;238(1):283-296. doi: 10.1111/nph.18731. Epub 2023 Feb 3.}, number = 1, pages = {283-296}, title = {Addressing controversies in the xylem embolism resistance-vessel diameter relationship}, type = {Journal Article}, volume = 238, year = 2023 }

%0 Journal Article %1 isasa2023addressing %A Isasa, E. %A Link, R. M. %A Jansen, S. %A Tezeh, F. R. %A Kaack, L. %A Sarmento Cabral, J. %A Schuldt, B. %D 2023 %J New Phytol %N 1 %P 283-296 %R 10.1111/nph.18731 %T Addressing controversies in the xylem embolism resistance-vessel diameter relationship %U https://www.ncbi.nlm.nih.gov/pubmed/36636783 %V 238 %X Although xylem embolism is a key process during drought-induced tree mortality, its relationship to wood anatomy remains debated. While the functional link between bordered pits and embolism resistance is known, there is no direct, mechanistic explanation for the traditional assumption that wider vessels are more vulnerable than narrow ones. We used data from 20 temperate broad-leaved tree species to study the inter- and intraspecific relationship of water potential at 50% loss of conductivity (P(50) ) with hydraulically weighted vessel diameter (D(h) ) and tested its link to pit membrane thickness (T(PM) ) and specific conductivity (K(s) ) on species level. Embolism-resistant species had thick pit membranes and narrow vessels. While D(h) was weakly associated with T(PM) , the P(50) -D(h) relationship remained highly significant after accounting for T(PM) . The interspecific pattern between P(50) and D(h) was mirrored by a link between P(50) and K(s) , but there was no evidence for an intraspecific relationship. Our results provide robust evidence for an interspecific P(50) -D(h) relationship across our species. As a potential cause for the inconsistencies in published P(50) -D(h) relationships, our analysis suggests differences in the range of trait values covered, and the level of data aggregation (species, tree or sample level) studied.
The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition. Amatobi, K. M.; Ozbek-Unal, A. G.; Schabler, S.; Deppisch, P.; Helfrich-Forster, C.; Mueller, M. J.; Wegener, C.; Fekete, A. In J Lipid Res, 64(10), p. 100417. 2023.
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Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period(01) clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality.

@article{amatobi2023circadian, abstract = {Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period(01) clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality.}, author = {Amatobi, K. M. and Ozbek-Unal, A. G. and Schabler, S. and Deppisch, P. and Helfrich-Forster, C. and Mueller, M. J. and Wegener, C. and Fekete, A.}, journal = {J Lipid Res}, keywords = {rhythm}, note = {Amatobi, Kelechi M Ozbek-Unal, Ayten Gizem Schabler, Stefan Deppisch, Peter Helfrich-Forster, Charlotte Mueller, Martin J Wegener, Christian Fekete, Agnes eng 2023/07/23 J Lipid Res. 2023 Oct;64(10):100417. doi: 10.1016/j.jlr.2023.100417. Epub 2023 Jul 20.}, number = 10, pages = 100417, title = {The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition}, type = {Journal Article}, volume = 64, year = 2023 }

%0 Journal Article %1 amatobi2023circadian %A Amatobi, K. M. %A Ozbek-Unal, A. G. %A Schabler, S. %A Deppisch, P. %A Helfrich-Forster, C. %A Mueller, M. J. %A Wegener, C. %A Fekete, A. %D 2023 %J J Lipid Res %N 10 %P 100417 %R 10.1016/j.jlr.2023.100417 %T The circadian clock is required for rhythmic lipid transport in Drosophila in interaction with diet and photic condition %U https://www.ncbi.nlm.nih.gov/pubmed/37481037https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10550813/pdf/main.pdf %V 64 %X Modern lifestyle is often at odds with endogenously driven rhythmicity, which can lead to circadian disruption and metabolic syndrome. One signature for circadian disruption is a reduced or altered metabolite cycling in the circulating tissue reflecting the current metabolic status. Drosophila is a well-established model in chronobiology, but day-time dependent variations of transport metabolites in the fly circulation are poorly characterized. Here, we sampled fly hemolymph throughout the day and analyzed diacylglycerols (DGs), phosphoethanolamines (PEs) and phosphocholines (PCs) using LC-MS. In wild-type flies kept on sugar-only medium under a light-dark cycle, all transport lipid species showed a synchronized bimodal oscillation pattern with maxima at the beginning and end of the light phase which were impaired in period(01) clock mutants. In wild-type flies under constant dark conditions, the oscillation became monophasic with a maximum in the middle of the subjective day. In strong support of clock-driven oscillations, levels of the targeted lipids peaked once in the middle of the light phase under time-restricted feeding independent of the time of food intake. When wild-type flies were reared on full standard medium, the rhythmic alterations of hemolymph lipid levels were greatly attenuated. Our data suggest that the circadian clock aligns daily oscillations of DGs, PEs, and PCs in the hemolymph to the anabolic siesta phase, with a strong influence of light on phase and modality.
Enhancing the structural diversity between forest patches-A concept and real-world experiment to study biodiversity, multifunctionality and forest resilience across spatial scales. Muller, J.; Mitesser, O.; Cadotte, M. W.; van der Plas, F.; Mori, A. S.; Ammer, C.; Chao, A.; Scherer-Lorenzen, M.; Baldrian, P.; Bassler, C.; Biedermann, P.; Cesarz, S.; Classen, A.; Delory, B. M.; Feldhaar, H.; Fichtner, A.; Hothorn, T.; Kuenzer, C.; Peters, M. K.; Pierick, K.; Schmitt, T.; Schuldt, B.; Seidel, D.; Six, D.; Steffan-Dewenter, I.; Thorn, S.; von Oheimb, G.; Wegmann, M.; Weisser, W. W.; Eisenhauer, N. In Glob Chang Biol, 29(6), pp. 1437–1450. 2023.
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Intensification of land use by humans has led to a homogenization of landscapes and decreasing resilience of ecosystems globally due to a loss of biodiversity, including the majority of forests. Biodiversity-ecosystem functioning (BEF) research has provided compelling evidence for a positive effect of biodiversity on ecosystem functions and services at the local (alpha-diversity) scale, but we largely lack empirical evidence on how the loss of between-patch beta-diversity affects biodiversity and multifunctionality at the landscape scale (gamma-diversity). Here, we present a novel concept and experimental framework for elucidating BEF patterns at alpha-, beta-, and gamma-scales in real landscapes at a forest management-relevant scale. We examine this framework using 22 temperate broadleaf production forests, dominated by Fagus sylvatica. In 11 of these forests, we manipulated the structure between forest patches by increasing variation in canopy cover and deadwood. We hypothesized that an increase in landscape heterogeneity would enhance the beta-diversity of different trophic levels, as well as the beta-functionality of various ecosystem functions. We will develop a new statistical framework for BEF studies extending across scales and incorporating biodiversity measures from taxonomic to functional to phylogenetic diversity using Hill numbers. We will further expand the Hill number concept to multifunctionality allowing the decomposition of gamma-multifunctionality into alpha- and beta-components. Combining this analytic framework with our experimental data will allow us to test how an increase in between patch heterogeneity affects biodiversity and multifunctionality across spatial scales and trophic levels to help inform and improve forest resilience under climate change. Such an integrative concept for biodiversity and functionality, including spatial scales and multiple aspects of diversity and multifunctionality as well as physical and environmental structure in forests, will go far beyond the current widely applied approach in forestry to increase resilience of future forests through the manipulation of tree species composition.

@article{muller2023enhancing, abstract = {Intensification of land use by humans has led to a homogenization of landscapes and decreasing resilience of ecosystems globally due to a loss of biodiversity, including the majority of forests. Biodiversity-ecosystem functioning (BEF) research has provided compelling evidence for a positive effect of biodiversity on ecosystem functions and services at the local (alpha-diversity) scale, but we largely lack empirical evidence on how the loss of between-patch beta-diversity affects biodiversity and multifunctionality at the landscape scale (gamma-diversity). Here, we present a novel concept and experimental framework for elucidating BEF patterns at alpha-, beta-, and gamma-scales in real landscapes at a forest management-relevant scale. We examine this framework using 22 temperate broadleaf production forests, dominated by Fagus sylvatica. In 11 of these forests, we manipulated the structure between forest patches by increasing variation in canopy cover and deadwood. We hypothesized that an increase in landscape heterogeneity would enhance the beta-diversity of different trophic levels, as well as the beta-functionality of various ecosystem functions. We will develop a new statistical framework for BEF studies extending across scales and incorporating biodiversity measures from taxonomic to functional to phylogenetic diversity using Hill numbers. We will further expand the Hill number concept to multifunctionality allowing the decomposition of gamma-multifunctionality into alpha- and beta-components. Combining this analytic framework with our experimental data will allow us to test how an increase in between patch heterogeneity affects biodiversity and multifunctionality across spatial scales and trophic levels to help inform and improve forest resilience under climate change. Such an integrative concept for biodiversity and functionality, including spatial scales and multiple aspects of diversity and multifunctionality as well as physical and environmental structure in forests, will go far beyond the current widely applied approach in forestry to increase resilience of future forests through the manipulation of tree species composition.}, author = {Muller, J. and Mitesser, O. and Cadotte, M. W. and van der Plas, F. and Mori, A. S. and Ammer, C. and Chao, A. and Scherer-Lorenzen, M. and Baldrian, P. and Bassler, C. and Biedermann, P. and Cesarz, S. and Classen, A. and Delory, B. M. and Feldhaar, H. and Fichtner, A. and Hothorn, T. and Kuenzer, C. and Peters, M. K. and Pierick, K. and Schmitt, T. and Schuldt, B. and Seidel, D. and Six, D. and Steffan-Dewenter, I. and Thorn, S. and von Oheimb, G. and Wegmann, M. and Weisser, W. W. and Eisenhauer, N.}, journal = {Glob Chang Biol}, keywords = {uni_network}, note = {Muller, Jorg Mitesser, Oliver Cadotte, Marc W van der Plas, Fons Mori, Akira S Ammer, Christian Chao, Anne Scherer-Lorenzen, Michael Baldrian, Petr Bassler, Claus Biedermann, Peter Cesarz, Simone Classen, Alice Delory, Benjamin M Feldhaar, Heike Fichtner, Andreas Hothorn, Torsten Kuenzer, Claudia Peters, Marcell K Pierick, Kerstin Schmitt, Thomas Schuldt, Bernhard Seidel, Dominik Six, Diana Steffan-Dewenter, Ingolf Thorn, Simon von Oheimb, Goddert Wegmann, Martin Weisser, Wolfgang W Eisenhauer, Nico eng 202548816/Deutsche Forschungsgemeinschaft/ 1956/1-1/Deutsche Forschungsgemeinschaft/ England 2022/12/30 Glob Chang Biol. 2023 Mar;29(6):1437-1450. doi: 10.1111/gcb.16564. Epub 2022 Dec 29.}, number = 6, pages = {1437-1450}, title = {Enhancing the structural diversity between forest patches-A concept and real-world experiment to study biodiversity, multifunctionality and forest resilience across spatial scales}, type = {Journal Article}, volume = 29, year = 2023 }

%0 Journal Article %1 muller2023enhancing %A Muller, J. %A Mitesser, O. %A Cadotte, M. W. %A van der Plas, F. %A Mori, A. S. %A Ammer, C. %A Chao, A. %A Scherer-Lorenzen, M. %A Baldrian, P. %A Bassler, C. %A Biedermann, P. %A Cesarz, S. %A Classen, A. %A Delory, B. M. %A Feldhaar, H. %A Fichtner, A. %A Hothorn, T. %A Kuenzer, C. %A Peters, M. K. %A Pierick, K. %A Schmitt, T. %A Schuldt, B. %A Seidel, D. %A Six, D. %A Steffan-Dewenter, I. %A Thorn, S. %A von Oheimb, G. %A Wegmann, M. %A Weisser, W. W. %A Eisenhauer, N. %D 2023 %J Glob Chang Biol %N 6 %P 1437-1450 %R 10.1111/gcb.16564 %T Enhancing the structural diversity between forest patches-A concept and real-world experiment to study biodiversity, multifunctionality and forest resilience across spatial scales %U https://www.ncbi.nlm.nih.gov/pubmed/36579623 %V 29 %X Intensification of land use by humans has led to a homogenization of landscapes and decreasing resilience of ecosystems globally due to a loss of biodiversity, including the majority of forests. Biodiversity-ecosystem functioning (BEF) research has provided compelling evidence for a positive effect of biodiversity on ecosystem functions and services at the local (alpha-diversity) scale, but we largely lack empirical evidence on how the loss of between-patch beta-diversity affects biodiversity and multifunctionality at the landscape scale (gamma-diversity). Here, we present a novel concept and experimental framework for elucidating BEF patterns at alpha-, beta-, and gamma-scales in real landscapes at a forest management-relevant scale. We examine this framework using 22 temperate broadleaf production forests, dominated by Fagus sylvatica. In 11 of these forests, we manipulated the structure between forest patches by increasing variation in canopy cover and deadwood. We hypothesized that an increase in landscape heterogeneity would enhance the beta-diversity of different trophic levels, as well as the beta-functionality of various ecosystem functions. We will develop a new statistical framework for BEF studies extending across scales and incorporating biodiversity measures from taxonomic to functional to phylogenetic diversity using Hill numbers. We will further expand the Hill number concept to multifunctionality allowing the decomposition of gamma-multifunctionality into alpha- and beta-components. Combining this analytic framework with our experimental data will allow us to test how an increase in between patch heterogeneity affects biodiversity and multifunctionality across spatial scales and trophic levels to help inform and improve forest resilience under climate change. Such an integrative concept for biodiversity and functionality, including spatial scales and multiple aspects of diversity and multifunctionality as well as physical and environmental structure in forests, will go far beyond the current widely applied approach in forestry to increase resilience of future forests through the manipulation of tree species composition.
Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species. Paligi, S. S.; Link, R. M.; Isasa, E.; Bittencourt, P.; Cabral, J. S.; Jansen, S.; Oliveira, R. S.; Pereira, L.; Schuldt, B. In Plant Biol (Stuttg), 25(7), pp. 1171–1185. 2023.
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The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.

@article{paligi2023assessing, abstract = {The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.}, author = {Paligi, S. S. and Link, R. M. and Isasa, E. and Bittencourt, P. and Cabral, J. S. and Jansen, S. and Oliveira, R. S. and Pereira, L. and Schuldt, B.}, journal = {Plant Biol (Stuttg)}, keywords = {*Trees}, note = {Paligi, S S Link, R M Isasa, E Bittencourt, P Cabral, J S Jansen, S Oliveira, R S Pereira, L Schuldt, B eng Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/ 457287575/Deutsche Forschungsgemeinschaft/ NF170370/Royal Society/ England 2023/09/13 Plant Biol (Stuttg). 2023 Dec;25(7):1171-1185. doi: 10.1111/plb.13573. Epub 2023 Sep 13.}, number = 7, pages = {1171-1185}, title = {Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species}, type = {Journal Article}, volume = 25, year = 2023 }

%0 Journal Article %1 paligi2023assessing %A Paligi, S. S. %A Link, R. M. %A Isasa, E. %A Bittencourt, P. %A Cabral, J. S. %A Jansen, S. %A Oliveira, R. S. %A Pereira, L. %A Schuldt, B. %D 2023 %J Plant Biol (Stuttg) %N 7 %P 1171-1185 %R 10.1111/plb.13573 %T Assessing the agreement between the pneumatic and the flow-centrifuge method for estimating xylem safety in temperate diffuse-porous tree species %U https://www.ncbi.nlm.nih.gov/pubmed/37703535 %V 25 %X The increasing frequency of global change-type droughts has created a need for fast, accurate and widely applicable techniques for estimating xylem embolism resistance to improve forecasts of future forest changes. We used data from 12 diffuse-porous temperate tree species covering a wide range of xylem safety to compare the pneumatic and flow-centrifuge method, two rapid methods used for constructing xylem vulnerability curves. We evaluated the agreement between parameters estimated with both methods and the sensitivity of pneumatic measurements to the duration of air discharge (AD) measurements. There was close agreement between xylem water potentials at 50% air discharged (PAD), estimated with the Pneumatron, and 50% loss of hydraulic conductivity (PLC), estimated with the flow-centrifuge method (mean signed deviation: 0.12 MPa, Pearson correlation: 0.96 after 15 s of gas extraction). However, the relationship between the estimated slopes was more variable, resulting in lower agreement in the xylem water potential at 12% and 88% PAD/PLC. The agreement between the two methods was not affected by species-specific vessel length distributions. All pneumatic parameters were sensitive to AD time. Overall agreement was highest at relatively short AD times, with an optimum at 16 s. Our results highlight the value of the Pneumatron as an easy and reliable tool to estimate 50% embolism thresholds for a wide range of diffuse-porous temperate angiosperms. Further, our study provides a set of useful metrics for methodological comparisons of vulnerability curves in terms of systematic and random deviations, as well as overall agreement.
Design of Glycoengineered IL-4 Antagonists Employing Chemical and Biosynthetic Glycosylation. Thomas, S.; Fiebig, J. E.; Kuhn, E. M.; Mayer, D. S.; Filbeck, S.; Schmitz, W.; Krischke, M.; Gropp, R.; Mueller, T. D. In ACS Omega, 8(28), pp. 24841–24852. 2023.
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Interleukin-4 (IL-4) plays a key role in atopic diseases. It coordinates T-helper cell differentiation to subtype 2, thereby directing defense toward humoral immunity. Together with Interleukin-13, IL-4 further induces immunoglobulin class switch to IgE. Antibodies of this type activate mast cells and basophilic and eosinophilic granulocytes, which release pro-inflammatory mediators accounting for the typical symptoms of atopic diseases. IL-4 and IL-13 are thus major targets for pharmaceutical intervention strategies to treat atopic diseases. Besides neutralizing antibodies against IL-4, IL-13, or its receptors, IL-4 antagonists can present valuable alternatives. Pitrakinra, an Escherichia coli-derived IL-4 antagonist, has been evaluated in clinical trials for asthma treatment in the past; however, deficits such as short serum lifetime and potential immunogenicity among others stopped further development. To overcome such deficits, PEGylation of therapeutically important proteins has been used to increase the lifetime and proteolytic stability. As an alternative, glycoengineering is an emerging strategy used to improve pharmacokinetics of protein therapeutics. In this study, we have established different strategies to attach glycan moieties to defined positions in IL-4. Different chemical attachment strategies employing thiol chemistry were used to attach a glucose molecule at amino acid position 121, thereby converting IL-4 into a highly effective antagonist. To enhance the proteolytic stability of this IL-4 antagonist, additional glycan structures were introduced by glycoengineering utilizing eucaryotic expression. IL-4 antagonists with a combination of chemical and biosynthetic glycoengineering could be useful as therapeutic alternatives to IL-4 neutralizing antibodies already used to treat atopic diseases.

@article{thomas2023design, abstract = {Interleukin-4 (IL-4) plays a key role in atopic diseases. It coordinates T-helper cell differentiation to subtype 2, thereby directing defense toward humoral immunity. Together with Interleukin-13, IL-4 further induces immunoglobulin class switch to IgE. Antibodies of this type activate mast cells and basophilic and eosinophilic granulocytes, which release pro-inflammatory mediators accounting for the typical symptoms of atopic diseases. IL-4 and IL-13 are thus major targets for pharmaceutical intervention strategies to treat atopic diseases. Besides neutralizing antibodies against IL-4, IL-13, or its receptors, IL-4 antagonists can present valuable alternatives. Pitrakinra, an Escherichia coli-derived IL-4 antagonist, has been evaluated in clinical trials for asthma treatment in the past; however, deficits such as short serum lifetime and potential immunogenicity among others stopped further development. To overcome such deficits, PEGylation of therapeutically important proteins has been used to increase the lifetime and proteolytic stability. As an alternative, glycoengineering is an emerging strategy used to improve pharmacokinetics of protein therapeutics. In this study, we have established different strategies to attach glycan moieties to defined positions in IL-4. Different chemical attachment strategies employing thiol chemistry were used to attach a glucose molecule at amino acid position 121, thereby converting IL-4 into a highly effective antagonist. To enhance the proteolytic stability of this IL-4 antagonist, additional glycan structures were introduced by glycoengineering utilizing eucaryotic expression. IL-4 antagonists with a combination of chemical and biosynthetic glycoengineering could be useful as therapeutic alternatives to IL-4 neutralizing antibodies already used to treat atopic diseases.}, author = {Thomas, S. and Fiebig, J. E. and Kuhn, E. M. and Mayer, D. S. and Filbeck, S. and Schmitz, W. and Krischke, M. and Gropp, R. and Mueller, T. D.}, journal = {ACS Omega}, keywords = {uni_network}, note = {Thomas, Sarah Fiebig, Juliane E Kuhn, Eva-Maria Mayer, Dominik S Filbeck, Sebastian Schmitz, Werner Krischke, Markus Gropp, Roswitha Mueller, Thomas D eng 2023/07/24 ACS Omega. 2023 Jul 5;8(28):24841-24852. doi: 10.1021/acsomega.3c00726. eCollection 2023 Jul 18.}, number = 28, pages = {24841-24852}, title = {Design of Glycoengineered IL-4 Antagonists Employing Chemical and Biosynthetic Glycosylation}, type = {Journal Article}, volume = 8, year = 2023 }

%0 Journal Article %1 thomas2023design %A Thomas, S. %A Fiebig, J. E. %A Kuhn, E. M. %A Mayer, D. S. %A Filbeck, S. %A Schmitz, W. %A Krischke, M. %A Gropp, R. %A Mueller, T. D. %D 2023 %J ACS Omega %N 28 %P 24841-24852 %R 10.1021/acsomega.3c00726 %T Design of Glycoengineered IL-4 Antagonists Employing Chemical and Biosynthetic Glycosylation %U https://www.ncbi.nlm.nih.gov/pubmed/37483220https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10357448/pdf/ao3c00726.pdf %V 8 %X Interleukin-4 (IL-4) plays a key role in atopic diseases. It coordinates T-helper cell differentiation to subtype 2, thereby directing defense toward humoral immunity. Together with Interleukin-13, IL-4 further induces immunoglobulin class switch to IgE. Antibodies of this type activate mast cells and basophilic and eosinophilic granulocytes, which release pro-inflammatory mediators accounting for the typical symptoms of atopic diseases. IL-4 and IL-13 are thus major targets for pharmaceutical intervention strategies to treat atopic diseases. Besides neutralizing antibodies against IL-4, IL-13, or its receptors, IL-4 antagonists can present valuable alternatives. Pitrakinra, an Escherichia coli-derived IL-4 antagonist, has been evaluated in clinical trials for asthma treatment in the past; however, deficits such as short serum lifetime and potential immunogenicity among others stopped further development. To overcome such deficits, PEGylation of therapeutically important proteins has been used to increase the lifetime and proteolytic stability. As an alternative, glycoengineering is an emerging strategy used to improve pharmacokinetics of protein therapeutics. In this study, we have established different strategies to attach glycan moieties to defined positions in IL-4. Different chemical attachment strategies employing thiol chemistry were used to attach a glucose molecule at amino acid position 121, thereby converting IL-4 into a highly effective antagonist. To enhance the proteolytic stability of this IL-4 antagonist, additional glycan structures were introduced by glycoengineering utilizing eucaryotic expression. IL-4 antagonists with a combination of chemical and biosynthetic glycoengineering could be useful as therapeutic alternatives to IL-4 neutralizing antibodies already used to treat atopic diseases.

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A nonfunctional copy of the salmonid sex-determining gene (sdY) is responsible for the "apparent" XY females in Chinook salmon, Oncorhynchus tshawytscha. Bertho, S.; Herpin, A.; Jouanno, E.; Yano, A.; Bobe, J.; Parrinello, H.; Journot, L.; Guyomard, R.; Muller, T.; Swanson, P.; McKinney, G.; Williamson, K.; Meek, M.; Schartl, M.; Guiguen, Y. In G3 (Bethesda), 12(2). 2022.
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Many salmonids have a male heterogametic (XX/XY) sex determination system, and they are supposed to have a conserved master sex-determining gene (sdY) that interacts at the protein level with Foxl2 leading to the blockage of the synergistic induction of Foxl2 and Nr5a1 of the cyp19a1a promoter. However, this hypothesis of a conserved master sex-determining role of sdY in salmonids is challenged by a few exceptions, one of them being the presence of naturally occurring "apparent" XY Chinook salmon, Oncorhynchus tshawytscha, females. Here, we show that some XY Chinook salmon females have a sdY gene (sdY-N183), with 1 missense mutation leading to a substitution of a conserved isoleucine to an asparagine (I183N). In contrast, Chinook salmon males have both a nonmutated sdY-I183 gene and the missense mutation sdY-N183 gene. The 3-dimensional model of SdY-I183N predicts that the I183N hydrophobic to hydrophilic amino acid change leads to a modification in the SdY beta-sandwich structure. Using in vitro cell transfection assays, we found that SdY-I183N, like the wild-type SdY, is preferentially localized in the cytoplasm. However, compared to wild-type SdY, SdY-I183N is more prone to degradation, its nuclear translocation by Foxl2 is reduced, and SdY-I183N is unable to significantly repress the synergistic Foxl2/Nr5a1 induction of the cyp19a1a promoter. Altogether, our results suggest that the sdY-N183 gene of XY Chinook females is nonfunctional and that SdY-I183N is no longer able to promote testicular differentiation by impairing the synthesis of estrogens in the early differentiating gonads of wild Chinook salmon XY females.

@article{bertho2022nonfunctional, abstract = {Many salmonids have a male heterogametic (XX/XY) sex determination system, and they are supposed to have a conserved master sex-determining gene (sdY) that interacts at the protein level with Foxl2 leading to the blockage of the synergistic induction of Foxl2 and Nr5a1 of the cyp19a1a promoter. However, this hypothesis of a conserved master sex-determining role of sdY in salmonids is challenged by a few exceptions, one of them being the presence of naturally occurring "apparent" XY Chinook salmon, Oncorhynchus tshawytscha, females. Here, we show that some XY Chinook salmon females have a sdY gene (sdY-N183), with 1 missense mutation leading to a substitution of a conserved isoleucine to an asparagine (I183N). In contrast, Chinook salmon males have both a nonmutated sdY-I183 gene and the missense mutation sdY-N183 gene. The 3-dimensional model of SdY-I183N predicts that the I183N hydrophobic to hydrophilic amino acid change leads to a modification in the SdY beta-sandwich structure. Using in vitro cell transfection assays, we found that SdY-I183N, like the wild-type SdY, is preferentially localized in the cytoplasm. However, compared to wild-type SdY, SdY-I183N is more prone to degradation, its nuclear translocation by Foxl2 is reduced, and SdY-I183N is unable to significantly repress the synergistic Foxl2/Nr5a1 induction of the cyp19a1a promoter. Altogether, our results suggest that the sdY-N183 gene of XY Chinook females is nonfunctional and that SdY-I183N is no longer able to promote testicular differentiation by impairing the synthesis of estrogens in the early differentiating gonads of wild Chinook salmon XY females.}, author = {Bertho, S. and Herpin, A. and Jouanno, E. and Yano, A. and Bobe, J. and Parrinello, H. and Journot, L. and Guyomard, R. and Muller, T. and Swanson, P. and McKinney, G. and Williamson, K. and Meek, M. and Schartl, M. and Guiguen, Y.}, journal = {G3 (Bethesda)}, keywords = {uni_network}, note = {Bertho, Sylvain Herpin, Amaury Jouanno, Elodie Yano, Ayaka Bobe, Julien Parrinello, Hugues Journot, Laurent Guyomard, Rene Muller, Thomas Swanson, Penny McKinney, Garrett Williamson, Kevin Meek, Mariah Schartl, Manfred Guiguen, Yann eng Research Support, Non-U.S. Gov't England 2022/02/01 G3 (Bethesda). 2022 Feb 4;12(2):jkab451. doi: 10.1093/g3journal/jkab451.}, number = 2, title = {A nonfunctional copy of the salmonid sex-determining gene (sdY) is responsible for the "apparent" XY females in Chinook salmon, Oncorhynchus tshawytscha}, type = {Journal Article}, volume = 12, year = 2022 }

%0 Journal Article %1 bertho2022nonfunctional %A Bertho, S. %A Herpin, A. %A Jouanno, E. %A Yano, A. %A Bobe, J. %A Parrinello, H. %A Journot, L. %A Guyomard, R. %A Muller, T. %A Swanson, P. %A McKinney, G. %A Williamson, K. %A Meek, M. %A Schartl, M. %A Guiguen, Y. %D 2022 %J G3 (Bethesda) %N 2 %R 10.1093/g3journal/jkab451 %T A nonfunctional copy of the salmonid sex-determining gene (sdY) is responsible for the "apparent" XY females in Chinook salmon, Oncorhynchus tshawytscha %U https://www.ncbi.nlm.nih.gov/pubmed/35100376https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8824802/pdf/jkab451.pdf %V 12 %X Many salmonids have a male heterogametic (XX/XY) sex determination system, and they are supposed to have a conserved master sex-determining gene (sdY) that interacts at the protein level with Foxl2 leading to the blockage of the synergistic induction of Foxl2 and Nr5a1 of the cyp19a1a promoter. However, this hypothesis of a conserved master sex-determining role of sdY in salmonids is challenged by a few exceptions, one of them being the presence of naturally occurring "apparent" XY Chinook salmon, Oncorhynchus tshawytscha, females. Here, we show that some XY Chinook salmon females have a sdY gene (sdY-N183), with 1 missense mutation leading to a substitution of a conserved isoleucine to an asparagine (I183N). In contrast, Chinook salmon males have both a nonmutated sdY-I183 gene and the missense mutation sdY-N183 gene. The 3-dimensional model of SdY-I183N predicts that the I183N hydrophobic to hydrophilic amino acid change leads to a modification in the SdY beta-sandwich structure. Using in vitro cell transfection assays, we found that SdY-I183N, like the wild-type SdY, is preferentially localized in the cytoplasm. However, compared to wild-type SdY, SdY-I183N is more prone to degradation, its nuclear translocation by Foxl2 is reduced, and SdY-I183N is unable to significantly repress the synergistic Foxl2/Nr5a1 induction of the cyp19a1a promoter. Altogether, our results suggest that the sdY-N183 gene of XY Chinook females is nonfunctional and that SdY-I183N is no longer able to promote testicular differentiation by impairing the synthesis of estrogens in the early differentiating gonads of wild Chinook salmon XY females.
Sugar perception in honeybees. Degirmenci, L.; Roge Ferreira, F. L.; Vukosavljevic, A.; Heindl, C.; Keller, A.; Geiger, D.; Scheiner, R. In Front Physiol, 13, p. 1089669. 2022.
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Honeybees (Apis mellifera) need their fine sense of taste to evaluate nectar and pollen sources. Gustatory receptors (Grs) translate taste signals into electrical responses. In vivo experiments have demonstrated collective responses of the whole Gr-set. We here disentangle the contributions of all three honeybee sugar receptors (AmGr1-3), combining CRISPR/Cas9 mediated genetic knock-out, electrophysiology and behaviour. We show an expanded sugar spectrum of the AmGr1 receptor. Mutants lacking AmGr1 have a reduced response to sucrose and glucose but not to fructose. AmGr2 solely acts as co-receptor of AmGr1 but not of AmGr3, as we show by electrophysiology and using bimolecular fluorescence complementation. Our results show for the first time that AmGr2 is indeed a functional receptor on its own. Intriguingly, AmGr2 mutants still display a wildtype-like sugar taste. AmGr3 is a specific fructose receptor and is not modulated by a co-receptor. Eliminating AmGr3 while preserving AmGr1 and AmGr2 abolishes the perception of fructose but not of sucrose. Our comprehensive study on the functions of AmGr1, AmGr2 and AmGr3 in honeybees is the first to combine investigations on sugar perception at the receptor level and simultaneously in vivo. We show that honeybees rely on two gustatory receptors to sense all relevant sugars.

@article{degirmenci2022sugar, abstract = {Honeybees (Apis mellifera) need their fine sense of taste to evaluate nectar and pollen sources. Gustatory receptors (Grs) translate taste signals into electrical responses. In vivo experiments have demonstrated collective responses of the whole Gr-set. We here disentangle the contributions of all three honeybee sugar receptors (AmGr1-3), combining CRISPR/Cas9 mediated genetic knock-out, electrophysiology and behaviour. We show an expanded sugar spectrum of the AmGr1 receptor. Mutants lacking AmGr1 have a reduced response to sucrose and glucose but not to fructose. AmGr2 solely acts as co-receptor of AmGr1 but not of AmGr3, as we show by electrophysiology and using bimolecular fluorescence complementation. Our results show for the first time that AmGr2 is indeed a functional receptor on its own. Intriguingly, AmGr2 mutants still display a wildtype-like sugar taste. AmGr3 is a specific fructose receptor and is not modulated by a co-receptor. Eliminating AmGr3 while preserving AmGr1 and AmGr2 abolishes the perception of fructose but not of sucrose. Our comprehensive study on the functions of AmGr1, AmGr2 and AmGr3 in honeybees is the first to combine investigations on sugar perception at the receptor level and simultaneously in vivo. We show that honeybees rely on two gustatory receptors to sense all relevant sugars.}, author = {Degirmenci, L. and Roge Ferreira, F. L. and Vukosavljevic, A. and Heindl, C. and Keller, A. and Geiger, D. and Scheiner, R.}, journal = {Front Physiol}, keywords = {AmGr1}, note = {Degirmenci, Laura Roge Ferreira, Fabio Luiz Vukosavljevic, Adrian Heindl, Cornelia Keller, Alexander Geiger, Dietmar Scheiner, Ricarda eng Switzerland 2023/01/31 Front Physiol. 2023 Jan 13;13:1089669. doi: 10.3389/fphys.2022.1089669. eCollection 2022.}, pages = 1089669, title = {Sugar perception in honeybees}, type = {Journal Article}, volume = 13, year = 2022 }

%0 Journal Article %1 degirmenci2022sugar %A Degirmenci, L. %A Roge Ferreira, F. L. %A Vukosavljevic, A. %A Heindl, C. %A Keller, A. %A Geiger, D. %A Scheiner, R. %D 2022 %J Front Physiol %P 1089669 %R 10.3389/fphys.2022.1089669 %T Sugar perception in honeybees %U https://www.ncbi.nlm.nih.gov/pubmed/36714315https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9880324/pdf/fphys-13-1089669.pdf %V 13 %X Honeybees (Apis mellifera) need their fine sense of taste to evaluate nectar and pollen sources. Gustatory receptors (Grs) translate taste signals into electrical responses. In vivo experiments have demonstrated collective responses of the whole Gr-set. We here disentangle the contributions of all three honeybee sugar receptors (AmGr1-3), combining CRISPR/Cas9 mediated genetic knock-out, electrophysiology and behaviour. We show an expanded sugar spectrum of the AmGr1 receptor. Mutants lacking AmGr1 have a reduced response to sucrose and glucose but not to fructose. AmGr2 solely acts as co-receptor of AmGr1 but not of AmGr3, as we show by electrophysiology and using bimolecular fluorescence complementation. Our results show for the first time that AmGr2 is indeed a functional receptor on its own. Intriguingly, AmGr2 mutants still display a wildtype-like sugar taste. AmGr3 is a specific fructose receptor and is not modulated by a co-receptor. Eliminating AmGr3 while preserving AmGr1 and AmGr2 abolishes the perception of fructose but not of sucrose. Our comprehensive study on the functions of AmGr1, AmGr2 and AmGr3 in honeybees is the first to combine investigations on sugar perception at the receptor level and simultaneously in vivo. We show that honeybees rely on two gustatory receptors to sense all relevant sugars.
The digestive systems of carnivorous plants. Freund, M.; Graus, D.; Fleischmann, A.; Gilbert, K. J.; Lin, Q.; Renner, T.; Stigloher, C.; Albert, V. A.; Hedrich, R.; Fukushima, K. In Plant Physiol, 190(1), pp. 44–59. 2022.
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To survive in the nutrient-poor habitats, carnivorous plants capture small organisms comprising complex substances not suitable for immediate reuse. The traps of carnivorous plants, which are analogous to the digestive systems of animals, are equipped with mechanisms for the breakdown and absorption of nutrients. Such capabilities have been acquired convergently over the past tens of millions of years in multiple angiosperm lineages by modifying plant-specific organs including leaves. The epidermis of carnivorous trap leaves bears groups of specialized cells called glands, which acquire substances from their prey via digestion and absorption. The digestive glands of carnivorous plants secrete mucilage, pitcher fluids, acids, and proteins, including digestive enzymes. The same (or morphologically distinct) glands then absorb the released compounds via various membrane transport proteins or endocytosis. Thus, these glands function in a manner similar to animal cells that are physiologically important in the digestive system, such as the parietal cells of the stomach and intestinal epithelial cells. Yet, carnivorous plants are equipped with strategies that deal with or incorporate plant-specific features, such as cell walls, epidermal cuticles, and phytohormones. In this review, we provide a systematic perspective on the digestive and absorptive capacity of convergently evolved carnivorous plants, with an emphasis on the forms and functions of glands.

@article{freund2022digestive, abstract = {To survive in the nutrient-poor habitats, carnivorous plants capture small organisms comprising complex substances not suitable for immediate reuse. The traps of carnivorous plants, which are analogous to the digestive systems of animals, are equipped with mechanisms for the breakdown and absorption of nutrients. Such capabilities have been acquired convergently over the past tens of millions of years in multiple angiosperm lineages by modifying plant-specific organs including leaves. The epidermis of carnivorous trap leaves bears groups of specialized cells called glands, which acquire substances from their prey via digestion and absorption. The digestive glands of carnivorous plants secrete mucilage, pitcher fluids, acids, and proteins, including digestive enzymes. The same (or morphologically distinct) glands then absorb the released compounds via various membrane transport proteins or endocytosis. Thus, these glands function in a manner similar to animal cells that are physiologically important in the digestive system, such as the parietal cells of the stomach and intestinal epithelial cells. Yet, carnivorous plants are equipped with strategies that deal with or incorporate plant-specific features, such as cell walls, epidermal cuticles, and phytohormones. In this review, we provide a systematic perspective on the digestive and absorptive capacity of convergently evolved carnivorous plants, with an emphasis on the forms and functions of glands.}, author = {Freund, M. and Graus, D. and Fleischmann, A. and Gilbert, K. J. and Lin, Q. and Renner, T. and Stigloher, C. and Albert, V. A. and Hedrich, R. and Fukushima, K.}, journal = {Plant Physiol}, keywords = {uni_network}, note = {Freund, Matthias Graus, Dorothea Fleischmann, Andreas Gilbert, Kadeem J Lin, Qianshi Renner, Tanya Stigloher, Christian Albert, Victor A Hedrich, Rainer Fukushima, Kenji eng Research Support, Non-U.S. Gov't Review 2022/05/24 Plant Physiol. 2022 Aug 29;190(1):44-59. doi: 10.1093/plphys/kiac232.}, number = 1, pages = {44-59}, title = {The digestive systems of carnivorous plants}, type = {Journal Article}, volume = 190, year = 2022 }

%0 Journal Article %1 freund2022digestive %A Freund, M. %A Graus, D. %A Fleischmann, A. %A Gilbert, K. J. %A Lin, Q. %A Renner, T. %A Stigloher, C. %A Albert, V. A. %A Hedrich, R. %A Fukushima, K. %D 2022 %J Plant Physiol %N 1 %P 44-59 %R 10.1093/plphys/kiac232 %T The digestive systems of carnivorous plants %U https://www.ncbi.nlm.nih.gov/pubmed/35604105https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9434158/pdf/kiac232.pdf %V 190 %X To survive in the nutrient-poor habitats, carnivorous plants capture small organisms comprising complex substances not suitable for immediate reuse. The traps of carnivorous plants, which are analogous to the digestive systems of animals, are equipped with mechanisms for the breakdown and absorption of nutrients. Such capabilities have been acquired convergently over the past tens of millions of years in multiple angiosperm lineages by modifying plant-specific organs including leaves. The epidermis of carnivorous trap leaves bears groups of specialized cells called glands, which acquire substances from their prey via digestion and absorption. The digestive glands of carnivorous plants secrete mucilage, pitcher fluids, acids, and proteins, including digestive enzymes. The same (or morphologically distinct) glands then absorb the released compounds via various membrane transport proteins or endocytosis. Thus, these glands function in a manner similar to animal cells that are physiologically important in the digestive system, such as the parietal cells of the stomach and intestinal epithelial cells. Yet, carnivorous plants are equipped with strategies that deal with or incorporate plant-specific features, such as cell walls, epidermal cuticles, and phytohormones. In this review, we provide a systematic perspective on the digestive and absorptive capacity of convergently evolved carnivorous plants, with an emphasis on the forms and functions of glands.
Site-Directed Immobilization of an Engineered Bone Morphogenetic Protein 2 (BMP2) Variant to Collagen-Based Microspheres Induces Bone Formation In Vivo. Siverino, C.; Fahmy-Garcia, S.; Mumcuoglu, D.; Oberwinkler, H.; Muehlemann, M.; Mueller, T.; Farrell, E.; van Osch, Gjvm; Nickel, J. In Int J Mol Sci, 23(7). 2022.
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For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2's bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs.

@article{siverino2022sitedirected, abstract = {For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2's bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs.}, author = {Siverino, C. and Fahmy-Garcia, S. and Mumcuoglu, D. and Oberwinkler, H. and Muehlemann, M. and Mueller, T. and Farrell, E. and van Osch, Gjvm and Nickel, J.}, journal = {Int J Mol Sci}, keywords = {Amino}, note = {Siverino, Claudia Fahmy-Garcia, Shorouk Mumcuoglu, Didem Oberwinkler, Heike Muehlemann, Markus Mueller, Thomas Farrell, Eric van Osch, Gerjo J V M Nickel, Joachim eng FP7/2007-2013/ under REA grant agreement no. 607051/European Union/ Switzerland 2022/04/13 Int J Mol Sci. 2022 Apr 1;23(7):3928. doi: 10.3390/ijms23073928.}, number = 7, title = {Site-Directed Immobilization of an Engineered Bone Morphogenetic Protein 2 (BMP2) Variant to Collagen-Based Microspheres Induces Bone Formation In Vivo}, type = {Journal Article}, volume = 23, year = 2022 }

%0 Journal Article %1 siverino2022sitedirected %A Siverino, C. %A Fahmy-Garcia, S. %A Mumcuoglu, D. %A Oberwinkler, H. %A Muehlemann, M. %A Mueller, T. %A Farrell, E. %A van Osch, Gjvm %A Nickel, J. %D 2022 %J Int J Mol Sci %N 7 %R 10.3390/ijms23073928 %T Site-Directed Immobilization of an Engineered Bone Morphogenetic Protein 2 (BMP2) Variant to Collagen-Based Microspheres Induces Bone Formation In Vivo %U https://www.ncbi.nlm.nih.gov/pubmed/35409290https://mdpi-res.com/d_attachment/ijms/ijms-23-03928/article_deploy/ijms-23-03928-v2.pdf?version=1649066584 %V 23 %X For the treatment of large bone defects, the commonly used technique of autologous bone grafting presents several drawbacks and limitations. With the discovery of the bone-inducing capabilities of bone morphogenetic protein 2 (BMP2), several delivery techniques were developed and translated to clinical applications. Implantation of scaffolds containing adsorbed BMP2 showed promising results. However, off-label use of this protein-scaffold combination caused severe complications due to an uncontrolled release of the growth factor, which has to be applied in supraphysiological doses in order to induce bone formation. Here, we propose an alternative strategy that focuses on the covalent immobilization of an engineered BMP2 variant to biocompatible scaffolds. The new BMP2 variant harbors an artificial amino acid with a specific functional group, allowing a site-directed covalent scaffold functionalization. The introduced artificial amino acid does not alter BMP2's bioactivity in vitro. When applied in vivo, the covalently coupled BMP2 variant induces the formation of bone tissue characterized by a structurally different morphology compared to that induced by the same scaffold containing ab-/adsorbed wild-type BMP2. Our results clearly show that this innovative technique comprises translational potential for the development of novel osteoinductive materials, improving safety for patients and reducing costs.
A unique inventory of ion transporters poises the Venus flytrap to fast-propagating action potentials and calcium waves. Scherzer, S.; Bohm, J.; Huang, S.; Iosip, A. L.; Kreuzer, I.; Becker, D.; Heckmann, M.; Al-Rasheid, K. A. S.; Dreyer, I.; Hedrich, R. In Curr Biol, 32(19), pp. 4255–4263 e5. 2022.
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Since the 19(th) century, it has been known that the carnivorous Venus flytrap is electrically excitable. Nevertheless, the mechanism and the molecular entities of the flytrap action potential (AP) remain unknown. When entering the electrically excitable stage, the trap expressed a characteristic inventory of ion transporters, among which the increase in glutamate receptor GLR3.6 RNA was most pronounced. Trigger hair stimulation or glutamate application evoked an AP and a cytoplasmic Ca(2+) transient that both propagated at the same speed from the site of induction along the entire trap lobe surface. A priming Ca(2+) moiety entering the cytoplasm in the context of the AP was further potentiated by an organelle-localized calcium-induced calcium release (CICR)-like system prolonging the Ca(2+) signal. While the Ca(2+) transient persisted, SKOR K(+) channels and AHA H(+)-ATPases repolarized the AP already. By counting the number of APs and long-lasting Ca(2+) transients, the trap directs the different steps in the carnivorous plant's hunting cycle. VIDEO ABSTRACT.

@article{scherzer2022unique, abstract = {Since the 19(th) century, it has been known that the carnivorous Venus flytrap is electrically excitable. Nevertheless, the mechanism and the molecular entities of the flytrap action potential (AP) remain unknown. When entering the electrically excitable stage, the trap expressed a characteristic inventory of ion transporters, among which the increase in glutamate receptor GLR3.6 RNA was most pronounced. Trigger hair stimulation or glutamate application evoked an AP and a cytoplasmic Ca(2+) transient that both propagated at the same speed from the site of induction along the entire trap lobe surface. A priming Ca(2+) moiety entering the cytoplasm in the context of the AP was further potentiated by an organelle-localized calcium-induced calcium release (CICR)-like system prolonging the Ca(2+) signal. While the Ca(2+) transient persisted, SKOR K(+) channels and AHA H(+)-ATPases repolarized the AP already. By counting the number of APs and long-lasting Ca(2+) transients, the trap directs the different steps in the carnivorous plant's hunting cycle. VIDEO ABSTRACT.}, author = {Scherzer, S. and Bohm, J. and Huang, S. and Iosip, A. L. and Kreuzer, I. and Becker, D. and Heckmann, M. and Al-Rasheid, K. A. S. and Dreyer, I. and Hedrich, R.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Scherzer, Sonke Bohm, Jennifer Huang, Shouguang Iosip, Anda L Kreuzer, Ines Becker, Dirk Heckmann, Manfred Al-Rasheid, Khaled A S Dreyer, Ingo Hedrich, Rainer eng Research Support, Non-U.S. Gov't Video-Audio Media England 2022/09/11 Curr Biol. 2022 Oct 10;32(19):4255-4263.e5. doi: 10.1016/j.cub.2022.08.051. Epub 2022 Sep 9.}, number = 19, pages = {4255-4263 e5}, title = {A unique inventory of ion transporters poises the Venus flytrap to fast-propagating action potentials and calcium waves}, type = {Journal Article}, volume = 32, year = 2022 }

%0 Journal Article %1 scherzer2022unique %A Scherzer, S. %A Bohm, J. %A Huang, S. %A Iosip, A. L. %A Kreuzer, I. %A Becker, D. %A Heckmann, M. %A Al-Rasheid, K. A. S. %A Dreyer, I. %A Hedrich, R. %D 2022 %J Curr Biol %N 19 %P 4255-4263 e5 %R 10.1016/j.cub.2022.08.051 %T A unique inventory of ion transporters poises the Venus flytrap to fast-propagating action potentials and calcium waves %U https://www.ncbi.nlm.nih.gov/pubmed/36087579 %V 32 %X Since the 19(th) century, it has been known that the carnivorous Venus flytrap is electrically excitable. Nevertheless, the mechanism and the molecular entities of the flytrap action potential (AP) remain unknown. When entering the electrically excitable stage, the trap expressed a characteristic inventory of ion transporters, among which the increase in glutamate receptor GLR3.6 RNA was most pronounced. Trigger hair stimulation or glutamate application evoked an AP and a cytoplasmic Ca(2+) transient that both propagated at the same speed from the site of induction along the entire trap lobe surface. A priming Ca(2+) moiety entering the cytoplasm in the context of the AP was further potentiated by an organelle-localized calcium-induced calcium release (CICR)-like system prolonging the Ca(2+) signal. While the Ca(2+) transient persisted, SKOR K(+) channels and AHA H(+)-ATPases repolarized the AP already. By counting the number of APs and long-lasting Ca(2+) transients, the trap directs the different steps in the carnivorous plant's hunting cycle. VIDEO ABSTRACT.
Stalk cell polar ion transport provide for bladder-based salinity tolerance in Chenopodium quinoa. Bazihizina, N.; Bohm, J.; Messerer, M.; Stigloher, C.; Muller, H. M.; Cuin, T. A.; Maierhofer, T.; Cabot, J.; Mayer, K. F. X.; Fella, C.; Huang, S.; Al-Rasheid, K. A. S.; Alquraishi, S.; Breadmore, M.; Mancuso, S.; Shabala, S.; Ache, P.; Zhang, H.; Zhu, J. K.; Hedrich, R.; Scherzer, S. In New Phytol, 235(5), pp. 1822–1835. 2022.
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Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder. Under salt stress, sodium (Na(+) ), chloride (Cl(-) ), potassium (K(+) ) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller. In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell's polar organization and bladder-directed solute flow. RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.

@article{bazihizina2022stalk, abstract = {Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder. Under salt stress, sodium (Na(+) ), chloride (Cl(-) ), potassium (K(+) ) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller. In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell's polar organization and bladder-directed solute flow. RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.}, author = {Bazihizina, N. and Bohm, J. and Messerer, M. and Stigloher, C. and Muller, H. M. and Cuin, T. A. and Maierhofer, T. and Cabot, J. and Mayer, K. F. X. and Fella, C. and Huang, S. and Al-Rasheid, K. A. S. and Alquraishi, S. and Breadmore, M. and Mancuso, S. and Shabala, S. and Ache, P. and Zhang, H. and Zhu, J. K. and Hedrich, R. and Scherzer, S.}, journal = {New Phytol}, keywords = {uni_network}, note = {Bazihizina, Nadia Bohm, Jennifer Messerer, Maxim Stigloher, Christian Muller, Heike M Cuin, Tracey Ann Maierhofer, Tobias Cabot, Joan Mayer, Klaus F X Fella, Christian Huang, Shouguang Al-Rasheid, Khaled A S Alquraishi, Saleh Breadmore, Michael Mancuso, Stefano Shabala, Sergey Ache, Peter Zhang, Heng Zhu, Jian-Kang Hedrich, Rainer Scherzer, Sonke eng Research Support, Non-U.S. Gov't England 2022/05/06 New Phytol. 2022 Sep;235(5):1822-1835. doi: 10.1111/nph.18205. Epub 2022 Jun 1.}, number = 5, pages = {1822-1835}, title = {Stalk cell polar ion transport provide for bladder-based salinity tolerance in Chenopodium quinoa}, type = {Journal Article}, volume = 235, year = 2022 }

%0 Journal Article %1 bazihizina2022stalk %A Bazihizina, N. %A Bohm, J. %A Messerer, M. %A Stigloher, C. %A Muller, H. M. %A Cuin, T. A. %A Maierhofer, T. %A Cabot, J. %A Mayer, K. F. X. %A Fella, C. %A Huang, S. %A Al-Rasheid, K. A. S. %A Alquraishi, S. %A Breadmore, M. %A Mancuso, S. %A Shabala, S. %A Ache, P. %A Zhang, H. %A Zhu, J. K. %A Hedrich, R. %A Scherzer, S. %D 2022 %J New Phytol %N 5 %P 1822-1835 %R 10.1111/nph.18205 %T Stalk cell polar ion transport provide for bladder-based salinity tolerance in Chenopodium quinoa %U https://www.ncbi.nlm.nih.gov/pubmed/35510810 %V 235 %X Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder. Under salt stress, sodium (Na(+) ), chloride (Cl(-) ), potassium (K(+) ) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller. In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell's polar organization and bladder-directed solute flow. RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.
Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap. Scherzer, S.; Huang, S.; Iosip, A.; Kreuzer, I.; Yokawa, K.; Al-Rasheid, K. A. S.; Heckmann, M.; Hedrich, R. In Sci Rep, 12(1), p. 2851. 2022.
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Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca(2+) wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K(+) channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrap's prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca(2+) first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca(2+) transients, we, in mature trigger hairs firing fast Ca(2+) signals and APs, found OSCA1.7 and GLR3.6 type Ca(2+) channels and ACA2/10 Ca(2+) pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca(2+) and electrical event. Given that anesthetics affect K(+) channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca(2+) and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca(2+) activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ.

@article{scherzer2022ether, abstract = {Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca(2+) wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K(+) channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrap's prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca(2+) first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca(2+) transients, we, in mature trigger hairs firing fast Ca(2+) signals and APs, found OSCA1.7 and GLR3.6 type Ca(2+) channels and ACA2/10 Ca(2+) pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca(2+) and electrical event. Given that anesthetics affect K(+) channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca(2+) and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca(2+) activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ.}, author = {Scherzer, S. and Huang, S. and Iosip, A. and Kreuzer, I. and Yokawa, K. and Al-Rasheid, K. A. S. and Heckmann, M. and Hedrich, R.}, journal = {Sci Rep}, keywords = {Potentials/genetics}, note = {Scherzer, Sonke Huang, Shouguang Iosip, Anda Kreuzer, Ines Yokawa, Ken Al-Rasheid, Khaled A S Heckmann, Manfred Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2022/02/20 Sci Rep. 2022 Feb 18;12(1):2851. doi: 10.1038/s41598-022-06915-z.}, number = 1, pages = 2851, title = {Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap}, type = {Journal Article}, volume = 12, year = 2022 }

%0 Journal Article %1 scherzer2022ether %A Scherzer, S. %A Huang, S. %A Iosip, A. %A Kreuzer, I. %A Yokawa, K. %A Al-Rasheid, K. A. S. %A Heckmann, M. %A Hedrich, R. %D 2022 %J Sci Rep %N 1 %P 2851 %R 10.1038/s41598-022-06915-z %T Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap %U https://www.ncbi.nlm.nih.gov/pubmed/35181728https://www.nature.com/articles/s41598-022-06915-z.pdf %V 12 %X Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca(2+) wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K(+) channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrap's prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca(2+) first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca(2+) transients, we, in mature trigger hairs firing fast Ca(2+) signals and APs, found OSCA1.7 and GLR3.6 type Ca(2+) channels and ACA2/10 Ca(2+) pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca(2+) and electrical event. Given that anesthetics affect K(+) channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca(2+) and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca(2+) activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ.

2021[ to top ]

Endocrine signals fine-tune daily activity patterns in Drosophila. Pauls, D.; Selcho, M.; Raderscheidt, J.; Amatobi, K. M.; Fekete, A.; Krischke, M.; Hermann-Luibl, C.; Ozbek-Unal, A. G.; Ehmann, N.; Itskov, P. M.; Kittel, R. J.; Helfrich-Forster, C.; Kuhnlein, R. P.; Mueller, M. J.; Wegener, C. In Curr Biol, 31(18), pp. 4076–4087 e5. 2021.
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Animals need to balance competitive behaviors to maintain internal homeostasis. The underlying mechanisms are complex but typically involve neuroendocrine signaling. Using Drosophila, we systematically manipulated signaling between energy-mobilizing endocrine cells producing adipokinetic hormone (AKH), octopaminergic neurons, and the energy-storing fat body to assess whether this neuroendocrine axis involved in starvation-induced hyperactivity also balances activity levels under ad libitum access to food. Our results suggest that AKH signals via two divergent pathways that are mutually competitive in terms of activity and rest. AKH increases activity via the octopaminergic system during the day, while it prevents high activity levels during the night by signaling to the fat body. This regulation involves feedback signaling from octopaminergic neurons to AKH-producing cells (APCs). APCs are known to integrate a multitude of metabolic and endocrine signals. Our results add a new facet to the versatile regulatory functions of APCs by showing that their output contributes to shape the daily activity pattern under ad libitum access to food.

@article{pauls2021endocrine, abstract = {Animals need to balance competitive behaviors to maintain internal homeostasis. The underlying mechanisms are complex but typically involve neuroendocrine signaling. Using Drosophila, we systematically manipulated signaling between energy-mobilizing endocrine cells producing adipokinetic hormone (AKH), octopaminergic neurons, and the energy-storing fat body to assess whether this neuroendocrine axis involved in starvation-induced hyperactivity also balances activity levels under ad libitum access to food. Our results suggest that AKH signals via two divergent pathways that are mutually competitive in terms of activity and rest. AKH increases activity via the octopaminergic system during the day, while it prevents high activity levels during the night by signaling to the fat body. This regulation involves feedback signaling from octopaminergic neurons to AKH-producing cells (APCs). APCs are known to integrate a multitude of metabolic and endocrine signals. Our results add a new facet to the versatile regulatory functions of APCs by showing that their output contributes to shape the daily activity pattern under ad libitum access to food.}, author = {Pauls, D. and Selcho, M. and Raderscheidt, J. and Amatobi, K. M. and Fekete, A. and Krischke, M. and Hermann-Luibl, C. and Ozbek-Unal, A. G. and Ehmann, N. and Itskov, P. M. and Kittel, R. J. and Helfrich-Forster, C. and Kuhnlein, R. P. and Mueller, M. J. and Wegener, C.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Pauls, Dennis Selcho, Mareike Raderscheidt, Johanna Amatobi, Kelechi M Fekete, Agnes Krischke, Markus Hermann-Luibl, Christiane Ozbek-Unal, Ayten Gizem Ehmann, Nadine Itskov, Pavel M Kittel, Robert J Helfrich-Forster, Charlotte Kuhnlein, Ronald P Mueller, Martin J Wegener, Christian eng Research Support, Non-U.S. Gov't England 2021/07/31 Curr Biol. 2021 Sep 27;31(18):4076-4087.e5. doi: 10.1016/j.cub.2021.07.002. Epub 2021 Jul 29.}, number = 18, pages = {4076-4087 e5}, title = {Endocrine signals fine-tune daily activity patterns in Drosophila}, type = {Journal Article}, volume = 31, year = 2021 }

%0 Journal Article %1 pauls2021endocrine %A Pauls, D. %A Selcho, M. %A Raderscheidt, J. %A Amatobi, K. M. %A Fekete, A. %A Krischke, M. %A Hermann-Luibl, C. %A Ozbek-Unal, A. G. %A Ehmann, N. %A Itskov, P. M. %A Kittel, R. J. %A Helfrich-Forster, C. %A Kuhnlein, R. P. %A Mueller, M. J. %A Wegener, C. %D 2021 %J Curr Biol %N 18 %P 4076-4087 e5 %R 10.1016/j.cub.2021.07.002 %T Endocrine signals fine-tune daily activity patterns in Drosophila %U https://www.ncbi.nlm.nih.gov/pubmed/34329588 %V 31 %X Animals need to balance competitive behaviors to maintain internal homeostasis. The underlying mechanisms are complex but typically involve neuroendocrine signaling. Using Drosophila, we systematically manipulated signaling between energy-mobilizing endocrine cells producing adipokinetic hormone (AKH), octopaminergic neurons, and the energy-storing fat body to assess whether this neuroendocrine axis involved in starvation-induced hyperactivity also balances activity levels under ad libitum access to food. Our results suggest that AKH signals via two divergent pathways that are mutually competitive in terms of activity and rest. AKH increases activity via the octopaminergic system during the day, while it prevents high activity levels during the night by signaling to the fat body. This regulation involves feedback signaling from octopaminergic neurons to AKH-producing cells (APCs). APCs are known to integrate a multitude of metabolic and endocrine signals. Our results add a new facet to the versatile regulatory functions of APCs by showing that their output contributes to shape the daily activity pattern under ad libitum access to food.
Optogenetic control of plant growth by a microbial rhodopsin. Zhou, Y.; Ding, M.; Gao, S.; Yu-Strzelczyk, J.; Krischke, M.; Duan, X.; Leide, J.; Riederer, M.; Mueller, M. J.; Hedrich, R.; Konrad, K. R.; Nagel, G. In Nat Plants, 7(2), pp. 144–151. 2021.
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While rhodopsin-based optogenetics has revolutionized neuroscience(1,2), poor expression of opsins and the absence of the essential cofactor all-trans-retinal has complicated the application of rhodopsins in plants. Here, we demonstrate retinal production in plants and improved rhodopsin targeting for green light manipulation of plant cells using the Guillardia theta light-gated anion channelrhodopsin GtACR1(3). Green light induces a massive increase in anion permeability and pronounced membrane potential changes when GtACR1 is expressed, enabling non-invasive manipulation of plant growth and leaf development. Using light-driven anion loss, we could mimic drought conditions and bring about leaf wilting despite sufficient water supply. Expressed in pollen tubes, global GtACR1 activation triggers membrane potential depolarizations due to large anion currents. While global illumination was associated with a reversible growth arrest, local GtACR1 activation at the flanks of the apical dome steers growth direction away from the side with increased anion conductance. These results suggest a crucial role of anion permeability for the guidance of pollen tube tip growth. This plant optogenetic approach could be expanded to create an entire pallet of rhodopsin-based tools(4), greatly facilitating dissection of plant ion-signalling pathways.

@article{zhou2021optogenetic, abstract = {While rhodopsin-based optogenetics has revolutionized neuroscience(1,2), poor expression of opsins and the absence of the essential cofactor all-trans-retinal has complicated the application of rhodopsins in plants. Here, we demonstrate retinal production in plants and improved rhodopsin targeting for green light manipulation of plant cells using the Guillardia theta light-gated anion channelrhodopsin GtACR1(3). Green light induces a massive increase in anion permeability and pronounced membrane potential changes when GtACR1 is expressed, enabling non-invasive manipulation of plant growth and leaf development. Using light-driven anion loss, we could mimic drought conditions and bring about leaf wilting despite sufficient water supply. Expressed in pollen tubes, global GtACR1 activation triggers membrane potential depolarizations due to large anion currents. While global illumination was associated with a reversible growth arrest, local GtACR1 activation at the flanks of the apical dome steers growth direction away from the side with increased anion conductance. These results suggest a crucial role of anion permeability for the guidance of pollen tube tip growth. This plant optogenetic approach could be expanded to create an entire pallet of rhodopsin-based tools(4), greatly facilitating dissection of plant ion-signalling pathways.}, author = {Zhou, Y. and Ding, M. and Gao, S. and Yu-Strzelczyk, J. and Krischke, M. and Duan, X. and Leide, J. and Riederer, M. and Mueller, M. J. and Hedrich, R. and Konrad, K. R. and Nagel, G.}, journal = {Nat Plants}, keywords = {uni_network}, note = {Zhou, Yang Ding, Meiqi Gao, Shiqiang Yu-Strzelczyk, Jing Krischke, Markus Duan, Xiaodong Leide, Jana Riederer, Markus Mueller, Martin J Hedrich, Rainer Konrad, Kai R Nagel, Georg eng England 2021/02/18 Nat Plants. 2021 Feb;7(2):144-151. doi: 10.1038/s41477-021-00853-w. Epub 2021 Feb 16.}, number = 2, pages = {144-151}, title = {Optogenetic control of plant growth by a microbial rhodopsin}, type = {Journal Article}, volume = 7, year = 2021 }

%0 Journal Article %1 zhou2021optogenetic %A Zhou, Y. %A Ding, M. %A Gao, S. %A Yu-Strzelczyk, J. %A Krischke, M. %A Duan, X. %A Leide, J. %A Riederer, M. %A Mueller, M. J. %A Hedrich, R. %A Konrad, K. R. %A Nagel, G. %D 2021 %J Nat Plants %N 2 %P 144-151 %R 10.1038/s41477-021-00853-w %T Optogenetic control of plant growth by a microbial rhodopsin %U https://www.ncbi.nlm.nih.gov/pubmed/33594268https://www.nature.com/articles/s41477-021-00853-w %V 7 %X While rhodopsin-based optogenetics has revolutionized neuroscience(1,2), poor expression of opsins and the absence of the essential cofactor all-trans-retinal has complicated the application of rhodopsins in plants. Here, we demonstrate retinal production in plants and improved rhodopsin targeting for green light manipulation of plant cells using the Guillardia theta light-gated anion channelrhodopsin GtACR1(3). Green light induces a massive increase in anion permeability and pronounced membrane potential changes when GtACR1 is expressed, enabling non-invasive manipulation of plant growth and leaf development. Using light-driven anion loss, we could mimic drought conditions and bring about leaf wilting despite sufficient water supply. Expressed in pollen tubes, global GtACR1 activation triggers membrane potential depolarizations due to large anion currents. While global illumination was associated with a reversible growth arrest, local GtACR1 activation at the flanks of the apical dome steers growth direction away from the side with increased anion conductance. These results suggest a crucial role of anion permeability for the guidance of pollen tube tip growth. This plant optogenetic approach could be expanded to create an entire pallet of rhodopsin-based tools(4), greatly facilitating dissection of plant ion-signalling pathways.
Reproducibility challenges in the search for antibacterial compounds from nature. Masota, N. E.; Vogg, G.; Ohlsen, K.; Holzgrabe, U. In PLoS One, 16(7), p. e0255437. 2021.
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BACKGROUND: Reproducibility of reported antibacterial activities of plant extracts has long remained questionable. Although plant-related factors should be well considered in serious pharmacognostic research, they are often not addressed in many research papers. Here we highlight the challenges in reproducing antibacterial activities of plant extracts. METHODS: Plants with reported antibacterial activities of interest were obtained from a literature review. Antibacterial activities against Escherichia coli and Klebsiella pneumoniae were tested using extracts' solutions in 10% DMSO and acetone. Compositions of working solutions from both solvents were established using LC-MS analysis. Moreover, the availability of details likely to affect reproducibility was evaluated in articles which reported antibacterial activities of studied plants. RESULTS: Inhibition of bacterial growth at MIC of 256-1024 mug/mL was observed in only 15.4% of identical plant species. These values were 4-16-fold higher than those reported earlier. Further, 18.2% of related plant species had MICs of 128-256 mug/mL. Besides, 29.2% and 95.8% of the extracts were soluble to sparingly soluble in 10% DMSO and acetone, respectively. Extracts' solutions in both solvents showed similar qualitative compositions, with differing quantities of corresponding phytochemicals. Details regarding seasons and growth state at collection were missing in 65% and 95% of evaluated articles, respectively. Likewise, solvents used to dissolve the extracts were lacking in 30% of the articles, whereas 40% of them used unidentified bacterial isolates. CONCLUSION: Reproducibility of previously reported activities from plants' extracts is a multi-factorial aspect. Thus, collective approaches are necessary in addressing the highlighted challenges.

@article{masota2021reproducibility, abstract = {BACKGROUND: Reproducibility of reported antibacterial activities of plant extracts has long remained questionable. Although plant-related factors should be well considered in serious pharmacognostic research, they are often not addressed in many research papers. Here we highlight the challenges in reproducing antibacterial activities of plant extracts. METHODS: Plants with reported antibacterial activities of interest were obtained from a literature review. Antibacterial activities against Escherichia coli and Klebsiella pneumoniae were tested using extracts' solutions in 10% DMSO and acetone. Compositions of working solutions from both solvents were established using LC-MS analysis. Moreover, the availability of details likely to affect reproducibility was evaluated in articles which reported antibacterial activities of studied plants. RESULTS: Inhibition of bacterial growth at MIC of 256-1024 mug/mL was observed in only 15.4% of identical plant species. These values were 4-16-fold higher than those reported earlier. Further, 18.2% of related plant species had MICs of 128-256 mug/mL. Besides, 29.2% and 95.8% of the extracts were soluble to sparingly soluble in 10% DMSO and acetone, respectively. Extracts' solutions in both solvents showed similar qualitative compositions, with differing quantities of corresponding phytochemicals. Details regarding seasons and growth state at collection were missing in 65% and 95% of evaluated articles, respectively. Likewise, solvents used to dissolve the extracts were lacking in 30% of the articles, whereas 40% of them used unidentified bacterial isolates. CONCLUSION: Reproducibility of previously reported activities from plants' extracts is a multi-factorial aspect. Thus, collective approaches are necessary in addressing the highlighted challenges.}, author = {Masota, N. E. and Vogg, G. and Ohlsen, K. and Holzgrabe, U.}, journal = {PLoS One}, keywords = {Agents}, note = {Masota, Nelson E Vogg, Gerd Ohlsen, Knut Holzgrabe, Ulrike eng Research Support, Non-U.S. Gov't 2021/07/30 PLoS One. 2021 Jul 29;16(7):e0255437. doi: 10.1371/journal.pone.0255437. eCollection 2021.}, number = 7, pages = {e0255437}, title = {Reproducibility challenges in the search for antibacterial compounds from nature}, type = {Journal Article}, volume = 16, year = 2021 }

%0 Journal Article %1 masota2021reproducibility %A Masota, N. E. %A Vogg, G. %A Ohlsen, K. %A Holzgrabe, U. %D 2021 %J PLoS One %N 7 %P e0255437 %R 10.1371/journal.pone.0255437 %T Reproducibility challenges in the search for antibacterial compounds from nature %U https://www.ncbi.nlm.nih.gov/pubmed/34324599https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0255437&type=printable %V 16 %X BACKGROUND: Reproducibility of reported antibacterial activities of plant extracts has long remained questionable. Although plant-related factors should be well considered in serious pharmacognostic research, they are often not addressed in many research papers. Here we highlight the challenges in reproducing antibacterial activities of plant extracts. METHODS: Plants with reported antibacterial activities of interest were obtained from a literature review. Antibacterial activities against Escherichia coli and Klebsiella pneumoniae were tested using extracts' solutions in 10% DMSO and acetone. Compositions of working solutions from both solvents were established using LC-MS analysis. Moreover, the availability of details likely to affect reproducibility was evaluated in articles which reported antibacterial activities of studied plants. RESULTS: Inhibition of bacterial growth at MIC of 256-1024 mug/mL was observed in only 15.4% of identical plant species. These values were 4-16-fold higher than those reported earlier. Further, 18.2% of related plant species had MICs of 128-256 mug/mL. Besides, 29.2% and 95.8% of the extracts were soluble to sparingly soluble in 10% DMSO and acetone, respectively. Extracts' solutions in both solvents showed similar qualitative compositions, with differing quantities of corresponding phytochemicals. Details regarding seasons and growth state at collection were missing in 65% and 95% of evaluated articles, respectively. Likewise, solvents used to dissolve the extracts were lacking in 30% of the articles, whereas 40% of them used unidentified bacterial isolates. CONCLUSION: Reproducibility of previously reported activities from plants' extracts is a multi-factorial aspect. Thus, collective approaches are necessary in addressing the highlighted challenges.
Mechanosensitive channel gating by delipidation. Flegler, V. J.; Rasmussen, A.; Borbil, K.; Boten, L.; Chen, H. A.; Deinlein, H.; Halang, J.; Hellmanzik, K.; Loffler, J.; Schmidt, V.; Makbul, C.; Kraft, C.; Hedrich, R.; Rasmussen, T.; Bottcher, B. In Proc Natl Acad Sci U S A, 118(33). 2021.
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The mechanosensitive channel of small conductance (MscS) protects bacteria against hypoosmotic shock. It can sense the tension in the surrounding membrane and releases solutes if the pressure in the cell is getting too high. The membrane contacts MscS at sensor paddles, but lipids also leave the membrane and move along grooves between the paddles to reside as far as 15 A away from the membrane in hydrophobic pockets. One sensing model suggests that a higher tension pulls lipids from the grooves back to the membrane, which triggers gating. However, it is still unclear to what degree this model accounts for sensing and what contribution the direct interaction of the membrane with the channel has. Here, we show that MscS opens when it is sufficiently delipidated by incubation with the detergent dodecyl-beta-maltoside or the branched detergent lauryl maltose neopentyl glycol. After addition of detergent-solubilized lipids, it closes again. These results support the model that lipid extrusion causes gating: Lipids are slowly removed from the grooves and pockets by the incubation with detergent, which triggers opening. Addition of lipids in micelles allows lipids to migrate back into the pockets, which closes the channel even in the absence of a membrane. Based on the distribution of the aliphatic chains in the open and closed conformation, we propose that during gating, lipids leave the complex on the cytosolic leaflet at the height of highest lateral tension, while on the periplasmic side, lipids flow into gaps, which open between transmembrane helices.

@article{flegler2021mechanosensitive, abstract = {The mechanosensitive channel of small conductance (MscS) protects bacteria against hypoosmotic shock. It can sense the tension in the surrounding membrane and releases solutes if the pressure in the cell is getting too high. The membrane contacts MscS at sensor paddles, but lipids also leave the membrane and move along grooves between the paddles to reside as far as 15 A away from the membrane in hydrophobic pockets. One sensing model suggests that a higher tension pulls lipids from the grooves back to the membrane, which triggers gating. However, it is still unclear to what degree this model accounts for sensing and what contribution the direct interaction of the membrane with the channel has. Here, we show that MscS opens when it is sufficiently delipidated by incubation with the detergent dodecyl-beta-maltoside or the branched detergent lauryl maltose neopentyl glycol. After addition of detergent-solubilized lipids, it closes again. These results support the model that lipid extrusion causes gating: Lipids are slowly removed from the grooves and pockets by the incubation with detergent, which triggers opening. Addition of lipids in micelles allows lipids to migrate back into the pockets, which closes the channel even in the absence of a membrane. Based on the distribution of the aliphatic chains in the open and closed conformation, we propose that during gating, lipids leave the complex on the cytosolic leaflet at the height of highest lateral tension, while on the periplasmic side, lipids flow into gaps, which open between transmembrane helices.}, author = {Flegler, V. J. and Rasmussen, A. and Borbil, K. and Boten, L. and Chen, H. A. and Deinlein, H. and Halang, J. and Hellmanzik, K. and Loffler, J. and Schmidt, V. and Makbul, C. and Kraft, C. and Hedrich, R. and Rasmussen, T. and Bottcher, B.}, journal = {Proc Natl Acad Sci U S A}, keywords = {Domain}, note = {Flegler, Vanessa Judith Rasmussen, Akiko Borbil, Karina Boten, Lea Chen, Hsuan-Ai Deinlein, Hanna Halang, Julia Hellmanzik, Kristin Loffler, Jessica Schmidt, Vanessa Makbul, Cihan Kraft, Christian Hedrich, Rainer Rasmussen, Tim Bottcher, Bettina eng Research Support, Non-U.S. Gov't 2021/08/12 Proc Natl Acad Sci U S A. 2021 Aug 17;118(33):e2107095118. doi: 10.1073/pnas.2107095118.}, number = 33, title = {Mechanosensitive channel gating by delipidation}, type = {Journal Article}, volume = 118, year = 2021 }

%0 Journal Article %1 flegler2021mechanosensitive %A Flegler, V. J. %A Rasmussen, A. %A Borbil, K. %A Boten, L. %A Chen, H. A. %A Deinlein, H. %A Halang, J. %A Hellmanzik, K. %A Loffler, J. %A Schmidt, V. %A Makbul, C. %A Kraft, C. %A Hedrich, R. %A Rasmussen, T. %A Bottcher, B. %D 2021 %J Proc Natl Acad Sci U S A %N 33 %R 10.1073/pnas.2107095118 %T Mechanosensitive channel gating by delipidation %U https://www.ncbi.nlm.nih.gov/pubmed/34376558https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8379960/pdf/pnas.202107095.pdf %V 118 %X The mechanosensitive channel of small conductance (MscS) protects bacteria against hypoosmotic shock. It can sense the tension in the surrounding membrane and releases solutes if the pressure in the cell is getting too high. The membrane contacts MscS at sensor paddles, but lipids also leave the membrane and move along grooves between the paddles to reside as far as 15 A away from the membrane in hydrophobic pockets. One sensing model suggests that a higher tension pulls lipids from the grooves back to the membrane, which triggers gating. However, it is still unclear to what degree this model accounts for sensing and what contribution the direct interaction of the membrane with the channel has. Here, we show that MscS opens when it is sufficiently delipidated by incubation with the detergent dodecyl-beta-maltoside or the branched detergent lauryl maltose neopentyl glycol. After addition of detergent-solubilized lipids, it closes again. These results support the model that lipid extrusion causes gating: Lipids are slowly removed from the grooves and pockets by the incubation with detergent, which triggers opening. Addition of lipids in micelles allows lipids to migrate back into the pockets, which closes the channel even in the absence of a membrane. Based on the distribution of the aliphatic chains in the open and closed conformation, we propose that during gating, lipids leave the complex on the cytosolic leaflet at the height of highest lateral tension, while on the periplasmic side, lipids flow into gaps, which open between transmembrane helices.
How to Grow a Tree: Plant Voltage-Dependent Cation Channels in the Spotlight of Evolution. Dreyer, I.; Sussmilch, F. C.; Fukushima, K.; Riadi, G.; Becker, D.; Schultz, J.; Hedrich, R. In Trends Plant Sci, 26(1), pp. 41–52. 2021.
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Phylogenetic analysis can be a powerful tool for generating hypotheses regarding the evolution of physiological processes. Here, we provide an updated view of the evolution of the main cation channels in plant electrical signalling: the Shaker family of voltage-gated potassium channels and the two-pore cation (K(+)) channel (TPC1) family. Strikingly, the TPC1 family followed the same conservative evolutionary path as one particular subfamily of Shaker channels (K(out)) and remained highly invariant after terrestrialisation, suggesting that electrical signalling was, and remains, key to survival on land. We note that phylogenetic analyses can have pitfalls, which may lead to erroneous conclusions. To avoid these in the future, we suggest guidelines for analyses of ion channel evolution in plants.

@article{dreyer2021plant, abstract = {Phylogenetic analysis can be a powerful tool for generating hypotheses regarding the evolution of physiological processes. Here, we provide an updated view of the evolution of the main cation channels in plant electrical signalling: the Shaker family of voltage-gated potassium channels and the two-pore cation (K(+)) channel (TPC1) family. Strikingly, the TPC1 family followed the same conservative evolutionary path as one particular subfamily of Shaker channels (K(out)) and remained highly invariant after terrestrialisation, suggesting that electrical signalling was, and remains, key to survival on land. We note that phylogenetic analyses can have pitfalls, which may lead to erroneous conclusions. To avoid these in the future, we suggest guidelines for analyses of ion channel evolution in plants.}, author = {Dreyer, I. and Sussmilch, F. C. and Fukushima, K. and Riadi, G. and Becker, D. and Schultz, J. and Hedrich, R.}, journal = {Trends Plant Sci}, keywords = {Cations}, note = {Dreyer, Ingo Sussmilch, Frances C Fukushima, Kenji Riadi, Gonzalo Becker, Dirk Schultz, Jorg Hedrich, Rainer eng Research Support, Non-U.S. Gov't Review England 2020/09/02 Trends Plant Sci. 2021 Jan;26(1):41-52. doi: 10.1016/j.tplants.2020.07.011. Epub 2020 Aug 29.}, number = 1, pages = {41-52}, title = {How to Grow a Tree: Plant Voltage-Dependent Cation Channels in the Spotlight of Evolution}, type = {Journal Article}, volume = 26, year = 2021 }

%0 Journal Article %1 dreyer2021plant %A Dreyer, I. %A Sussmilch, F. C. %A Fukushima, K. %A Riadi, G. %A Becker, D. %A Schultz, J. %A Hedrich, R. %D 2021 %J Trends Plant Sci %N 1 %P 41-52 %R 10.1016/j.tplants.2020.07.011 %T How to Grow a Tree: Plant Voltage-Dependent Cation Channels in the Spotlight of Evolution %U https://www.ncbi.nlm.nih.gov/pubmed/32868178 %V 26 %X Phylogenetic analysis can be a powerful tool for generating hypotheses regarding the evolution of physiological processes. Here, we provide an updated view of the evolution of the main cation channels in plant electrical signalling: the Shaker family of voltage-gated potassium channels and the two-pore cation (K(+)) channel (TPC1) family. Strikingly, the TPC1 family followed the same conservative evolutionary path as one particular subfamily of Shaker channels (K(out)) and remained highly invariant after terrestrialisation, suggesting that electrical signalling was, and remains, key to survival on land. We note that phylogenetic analyses can have pitfalls, which may lead to erroneous conclusions. To avoid these in the future, we suggest guidelines for analyses of ion channel evolution in plants.
Plant roots employ cell-layer-specific programs to respond to pathogenic and beneficial microbes. Froschel, C.; Komorek, J.; Attard, A.; Marsell, A.; Lopez-Arboleda, W. A.; Le Berre, J.; Wolf, E.; Geldner, N.; Waller, F.; Korte, A.; Droge-Laser, W. In Cell Host Microbe, 29(2), pp. 299–310 e7. 2021.
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Plant roots are built of concentric cell layers that are thought to respond to microbial infections by employing specific, genetically defined programs. Yet, the functional impact of this radial organization remains elusive, particularly due to the lack of genome-wide techniques for monitoring expression at a cell-layer resolution. Here, cell-type-specific expression of tagged ribosomes enabled the isolation of ribosome-bound mRNA to obtain cell-layer translatomes (TRAP-seq, translating ribosome affinity purification and RNA sequencing). After inoculation with the vascular pathogen Verticillium longisporum, pathogenic oomycete Phytophthora parasitica, or mutualistic endophyte Serendipita indica, root cell-layer responses reflected the fundamentally different colonization strategies of these microbes. Notably, V. longisporum specifically suppressed the endodermal barrier, which restricts fungal progression, allowing microbial access to the root central cylinder. Moreover, localized biosynthesis of antimicrobial compounds and ethylene differed in response to pathogens and mutualists. These examples highlight the power of this resource to gain insights into root-microbe interactions and to develop strategies in crop improvement.

@article{froschel2021plant, abstract = {Plant roots are built of concentric cell layers that are thought to respond to microbial infections by employing specific, genetically defined programs. Yet, the functional impact of this radial organization remains elusive, particularly due to the lack of genome-wide techniques for monitoring expression at a cell-layer resolution. Here, cell-type-specific expression of tagged ribosomes enabled the isolation of ribosome-bound mRNA to obtain cell-layer translatomes (TRAP-seq, translating ribosome affinity purification and RNA sequencing). After inoculation with the vascular pathogen Verticillium longisporum, pathogenic oomycete Phytophthora parasitica, or mutualistic endophyte Serendipita indica, root cell-layer responses reflected the fundamentally different colonization strategies of these microbes. Notably, V. longisporum specifically suppressed the endodermal barrier, which restricts fungal progression, allowing microbial access to the root central cylinder. Moreover, localized biosynthesis of antimicrobial compounds and ethylene differed in response to pathogens and mutualists. These examples highlight the power of this resource to gain insights into root-microbe interactions and to develop strategies in crop improvement.}, author = {Froschel, C. and Komorek, J. and Attard, A. and Marsell, A. and Lopez-Arboleda, W. A. and Le Berre, J. and Wolf, E. and Geldner, N. and Waller, F. and Korte, A. and Droge-Laser, W.}, journal = {Cell Host Microbe}, keywords = {Arabidopsis/*microbiology/physiology}, note = {Froschel, Christian Komorek, Jaqueline Attard, Agnes Marsell, Alexander Lopez-Arboleda, William A Le Berre, Joelle Wolf, Elmar Geldner, Niko Waller, Frank Korte, Arthur Droge-Laser, Wolfgang eng 2020/12/31 Cell Host Microbe. 2021 Feb 10;29(2):299-310.e7. doi: 10.1016/j.chom.2020.11.014. Epub 2020 Dec 29.}, number = 2, pages = {299-310 e7}, title = {Plant roots employ cell-layer-specific programs to respond to pathogenic and beneficial microbes}, type = {Journal Article}, volume = 29, year = 2021 }

%0 Journal Article %1 froschel2021plant %A Froschel, C. %A Komorek, J. %A Attard, A. %A Marsell, A. %A Lopez-Arboleda, W. A. %A Le Berre, J. %A Wolf, E. %A Geldner, N. %A Waller, F. %A Korte, A. %A Droge-Laser, W. %D 2021 %J Cell Host Microbe %N 2 %P 299-310 e7 %R 10.1016/j.chom.2020.11.014 %T Plant roots employ cell-layer-specific programs to respond to pathogenic and beneficial microbes %U https://www.ncbi.nlm.nih.gov/pubmed/33378688 %V 29 %X Plant roots are built of concentric cell layers that are thought to respond to microbial infections by employing specific, genetically defined programs. Yet, the functional impact of this radial organization remains elusive, particularly due to the lack of genome-wide techniques for monitoring expression at a cell-layer resolution. Here, cell-type-specific expression of tagged ribosomes enabled the isolation of ribosome-bound mRNA to obtain cell-layer translatomes (TRAP-seq, translating ribosome affinity purification and RNA sequencing). After inoculation with the vascular pathogen Verticillium longisporum, pathogenic oomycete Phytophthora parasitica, or mutualistic endophyte Serendipita indica, root cell-layer responses reflected the fundamentally different colonization strategies of these microbes. Notably, V. longisporum specifically suppressed the endodermal barrier, which restricts fungal progression, allowing microbial access to the root central cylinder. Moreover, localized biosynthesis of antimicrobial compounds and ethylene differed in response to pathogens and mutualists. These examples highlight the power of this resource to gain insights into root-microbe interactions and to develop strategies in crop improvement.
The Developmental and Genetic Architecture of the Sexually Selected Male Ornament of Swordtails. Schartl, M.; Kneitz, S.; Ormanns, J.; Schmidt, C.; Anderson, J. L.; Amores, A.; Catchen, J.; Wilson, C.; Geiger, D.; Du, K.; Garcia-Olazabal, M.; Sudaram, S.; Winkler, C.; Hedrich, R.; Warren, W. C.; Walter, R.; Meyer, A.; Postlethwait, J. H. In Curr Biol, 31(5), pp. 911–922 e4. 2021.
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Sexual selection results in sex-specific characters like the conspicuously pigmented extension of the ventral tip of the caudal fin-the "sword"-in males of several species of Xiphophorus fishes. To uncover the genetic architecture underlying sword formation and to identify genes that are associated with its development, we characterized the sword transcriptional profile and combined it with genetic mapping approaches. Results showed that the male ornament of swordtails develops from a sexually non-dimorphic prepattern of transcription factors in the caudal fin. Among genes that constitute the exclusive sword transcriptome and are located in the genomic region associated with this trait we identify the potassium channel, Kcnh8, as a sword development gene. In addition to its neural function kcnh8 performs a known role in fin growth. These findings indicate that during evolution of swordtails a brain gene has been co-opted for an additional novel function in establishing a male ornament.

@article{schartl2021developmental, abstract = {Sexual selection results in sex-specific characters like the conspicuously pigmented extension of the ventral tip of the caudal fin-the "sword"-in males of several species of Xiphophorus fishes. To uncover the genetic architecture underlying sword formation and to identify genes that are associated with its development, we characterized the sword transcriptional profile and combined it with genetic mapping approaches. Results showed that the male ornament of swordtails develops from a sexually non-dimorphic prepattern of transcription factors in the caudal fin. Among genes that constitute the exclusive sword transcriptome and are located in the genomic region associated with this trait we identify the potassium channel, Kcnh8, as a sword development gene. In addition to its neural function kcnh8 performs a known role in fin growth. These findings indicate that during evolution of swordtails a brain gene has been co-opted for an additional novel function in establishing a male ornament.}, author = {Schartl, M. and Kneitz, S. and Ormanns, J. and Schmidt, C. and Anderson, J. L. and Amores, A. and Catchen, J. and Wilson, C. and Geiger, D. and Du, K. and Garcia-Olazabal, M. and Sudaram, S. and Winkler, C. and Hedrich, R. and Warren, W. C. and Walter, R. and Meyer, A. and Postlethwait, J. H.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Schartl, Manfred Kneitz, Susanne Ormanns, Jenny Schmidt, Cornelia Anderson, Jennifer L Amores, Angel Catchen, Julian Wilson, Catherine Geiger, Dietmar Du, Kang Garcia-Olazabal, Mateo Sudaram, Sudha Winkler, Christoph Hedrich, Rainer Warren, Wesley C Walter, Ronald Meyer, Axel Postlethwait, John H eng R24 RR032658/RR/NCRR NIH HHS/ R35 GM139635/GM/NIGMS NIH HHS/ R01 OD011116/OD/NIH HHS/ R24 OD018555/OD/NIH HHS/ R01 GM085318/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't England 2020/12/05 Curr Biol. 2021 Mar 8;31(5):911-922.e4. doi: 10.1016/j.cub.2020.11.028. Epub 2020 Dec 3.}, number = 5, pages = {911-922 e4}, title = {The Developmental and Genetic Architecture of the Sexually Selected Male Ornament of Swordtails}, type = {Journal Article}, volume = 31, year = 2021 }

%0 Journal Article %1 schartl2021developmental %A Schartl, M. %A Kneitz, S. %A Ormanns, J. %A Schmidt, C. %A Anderson, J. L. %A Amores, A. %A Catchen, J. %A Wilson, C. %A Geiger, D. %A Du, K. %A Garcia-Olazabal, M. %A Sudaram, S. %A Winkler, C. %A Hedrich, R. %A Warren, W. C. %A Walter, R. %A Meyer, A. %A Postlethwait, J. H. %D 2021 %J Curr Biol %N 5 %P 911-922 e4 %R 10.1016/j.cub.2020.11.028 %T The Developmental and Genetic Architecture of the Sexually Selected Male Ornament of Swordtails %U https://www.ncbi.nlm.nih.gov/pubmed/33275891https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8580132/pdf/nihms-1648538.pdf %V 31 %X Sexual selection results in sex-specific characters like the conspicuously pigmented extension of the ventral tip of the caudal fin-the "sword"-in males of several species of Xiphophorus fishes. To uncover the genetic architecture underlying sword formation and to identify genes that are associated with its development, we characterized the sword transcriptional profile and combined it with genetic mapping approaches. Results showed that the male ornament of swordtails develops from a sexually non-dimorphic prepattern of transcription factors in the caudal fin. Among genes that constitute the exclusive sword transcriptome and are located in the genomic region associated with this trait we identify the potassium channel, Kcnh8, as a sword development gene. In addition to its neural function kcnh8 performs a known role in fin growth. These findings indicate that during evolution of swordtails a brain gene has been co-opted for an additional novel function in establishing a male ornament.
In Vitro Rearing Changes Social Task Performance and Physiology in Honeybees. Schilcher, F.; Hilsmann, L.; Rauscher, L.; Degirmenci, L.; Krischke, M.; Krischke, B.; Ankenbrand, M.; Rutschmann, B.; Mueller, M. J.; Steffan-Dewenter, I.; Scheiner, R. In Insects, 13(1). 2021.
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In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees.

@article{schilcher2021vitro, abstract = {In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees.}, author = {Schilcher, F. and Hilsmann, L. and Rauscher, L. and Degirmenci, L. and Krischke, M. and Krischke, B. and Ankenbrand, M. and Rutschmann, B. and Mueller, M. J. and Steffan-Dewenter, I. and Scheiner, R.}, journal = {Insects}, keywords = {Per}, note = {Schilcher, Felix Hilsmann, Lioba Rauscher, Lisa Degirmenci, Laura Krischke, Markus Krischke, Beate Ankenbrand, Markus Rutschmann, Benjamin Mueller, Martin J Steffan-Dewenter, Ingolf Scheiner, Ricarda eng SCHE 1573/9-1/Deutsche Forschungsgemeinschaft/ HA 5324/2-1/Deutsche Forschungsgemeinschaft/ Switzerland 2022/01/22 Insects. 2021 Dec 21;13(1):4. doi: 10.3390/insects13010004.}, number = 1, title = {In Vitro Rearing Changes Social Task Performance and Physiology in Honeybees}, type = {Journal Article}, volume = 13, year = 2021 }

%0 Journal Article %1 schilcher2021vitro %A Schilcher, F. %A Hilsmann, L. %A Rauscher, L. %A Degirmenci, L. %A Krischke, M. %A Krischke, B. %A Ankenbrand, M. %A Rutschmann, B. %A Mueller, M. J. %A Steffan-Dewenter, I. %A Scheiner, R. %D 2021 %J Insects %N 1 %R 10.3390/insects13010004 %T In Vitro Rearing Changes Social Task Performance and Physiology in Honeybees %U https://www.ncbi.nlm.nih.gov/pubmed/35055848https://mdpi-res.com/d_attachment/insects/insects-13-00004/article_deploy/insects-13-00004-v2.pdf?version=1640167247 %V 13 %X In vitro rearing of honeybee larvae is an established method that enables exact control and monitoring of developmental factors and allows controlled application of pesticides or pathogens. However, only a few studies have investigated how the rearing method itself affects the behavior of the resulting adult honeybees. We raised honeybees in vitro according to a standardized protocol: marking the emerging honeybees individually and inserting them into established colonies. Subsequently, we investigated the behavioral performance of nurse bees and foragers and quantified the physiological factors underlying the social organization. Adult honeybees raised in vitro differed from naturally reared honeybees in their probability of performing social tasks. Further, in vitro-reared bees foraged for a shorter duration in their life and performed fewer foraging trips. Nursing behavior appeared to be unaffected by rearing condition. Weight was also unaffected by rearing condition. Interestingly, juvenile hormone titers, which normally increase strongly around the time when a honeybee becomes a forager, were significantly lower in three- and four-week-old in vitro bees. The effects of the rearing environment on individual sucrose responsiveness and lipid levels were rather minor. These data suggest that larval rearing conditions can affect the task performance and physiology of adult bees despite equal weight, pointing to an important role of the colony environment for these factors. Our observations of behavior and metabolic pathways offer important novel insight into how the rearing environment affects adult honeybees.
Perturbations in plant energy homeostasis prime lateral root initiation via SnRK1-bZIP63-ARF19 signaling. Muralidhara, P.; Weiste, C.; Collani, S.; Krischke, M.; Kreisz, P.; Draken, J.; Feil, R.; Mair, A.; Teige, M.; Muller, M. J.; Schmid, M.; Becker, D.; Lunn, J. E.; Rolland, F.; Hanson, J.; Droge-Laser, W. In Proc Natl Acad Sci U S A, 118(37). 2021.
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Plants adjust their energy metabolism to continuous environmental fluctuations, resulting in a tremendous plasticity in their architecture. The regulatory circuits involved, however, remain largely unresolved. In Arabidopsis, moderate perturbations in photosynthetic activity, administered by short-term low light exposure or unexpected darkness, lead to increased lateral root (LR) initiation. Consistent with expression of low-energy markers, these treatments alter energy homeostasis and reduce sugar availability in roots. Here, we demonstrate that the LR response requires the metabolic stress sensor kinase Snf1-RELATED-KINASE1 (SnRK1), which phosphorylates the transcription factor BASIC LEUCINE ZIPPER63 (bZIP63) that directly binds and activates the promoter of AUXIN RESPONSE FACTOR19 (ARF19), a key regulator of LR initiation. Consistently, starvation-induced ARF19 transcription is impaired in bzip63 mutants. This study highlights a positive developmental function of SnRK1. During energy limitation, LRs are initiated and primed for outgrowth upon recovery. Hence, this study provides mechanistic insights into how energy shapes the agronomically important root system.

@article{muralidhara2021perturbations, abstract = {Plants adjust their energy metabolism to continuous environmental fluctuations, resulting in a tremendous plasticity in their architecture. The regulatory circuits involved, however, remain largely unresolved. In Arabidopsis, moderate perturbations in photosynthetic activity, administered by short-term low light exposure or unexpected darkness, lead to increased lateral root (LR) initiation. Consistent with expression of low-energy markers, these treatments alter energy homeostasis and reduce sugar availability in roots. Here, we demonstrate that the LR response requires the metabolic stress sensor kinase Snf1-RELATED-KINASE1 (SnRK1), which phosphorylates the transcription factor BASIC LEUCINE ZIPPER63 (bZIP63) that directly binds and activates the promoter of AUXIN RESPONSE FACTOR19 (ARF19), a key regulator of LR initiation. Consistently, starvation-induced ARF19 transcription is impaired in bzip63 mutants. This study highlights a positive developmental function of SnRK1. During energy limitation, LRs are initiated and primed for outgrowth upon recovery. Hence, this study provides mechanistic insights into how energy shapes the agronomically important root system.}, author = {Muralidhara, P. and Weiste, C. and Collani, S. and Krischke, M. and Kreisz, P. and Draken, J. and Feil, R. and Mair, A. and Teige, M. and Muller, M. J. and Schmid, M. and Becker, D. and Lunn, J. E. and Rolland, F. and Hanson, J. and Droge-Laser, W.}, journal = {Proc Natl Acad Sci U S A}, keywords = {development/metabolism}, note = {Muralidhara, Prathibha Weiste, Christoph Collani, Silvio Krischke, Markus Kreisz, Philipp Draken, Jan Feil, Regina Mair, Andrea Teige, Markus Muller, Martin J Schmid, Markus Becker, Dirk Lunn, John E Rolland, Filip Hanson, Johannes Droge-Laser, Wolfgang eng Research Support, Non-U.S. Gov't 2021/09/11 Proc Natl Acad Sci U S A. 2021 Sep 14;118(37):e2106961118. doi: 10.1073/pnas.2106961118.}, number = 37, title = {Perturbations in plant energy homeostasis prime lateral root initiation via SnRK1-bZIP63-ARF19 signaling}, type = {Journal Article}, volume = 118, year = 2021 }

%0 Journal Article %1 muralidhara2021perturbations %A Muralidhara, P. %A Weiste, C. %A Collani, S. %A Krischke, M. %A Kreisz, P. %A Draken, J. %A Feil, R. %A Mair, A. %A Teige, M. %A Muller, M. J. %A Schmid, M. %A Becker, D. %A Lunn, J. E. %A Rolland, F. %A Hanson, J. %A Droge-Laser, W. %D 2021 %J Proc Natl Acad Sci U S A %N 37 %R 10.1073/pnas.2106961118 %T Perturbations in plant energy homeostasis prime lateral root initiation via SnRK1-bZIP63-ARF19 signaling %U https://www.ncbi.nlm.nih.gov/pubmed/34504003https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8449399/pdf/pnas.202106961.pdf %V 118 %X Plants adjust their energy metabolism to continuous environmental fluctuations, resulting in a tremendous plasticity in their architecture. The regulatory circuits involved, however, remain largely unresolved. In Arabidopsis, moderate perturbations in photosynthetic activity, administered by short-term low light exposure or unexpected darkness, lead to increased lateral root (LR) initiation. Consistent with expression of low-energy markers, these treatments alter energy homeostasis and reduce sugar availability in roots. Here, we demonstrate that the LR response requires the metabolic stress sensor kinase Snf1-RELATED-KINASE1 (SnRK1), which phosphorylates the transcription factor BASIC LEUCINE ZIPPER63 (bZIP63) that directly binds and activates the promoter of AUXIN RESPONSE FACTOR19 (ARF19), a key regulator of LR initiation. Consistently, starvation-induced ARF19 transcription is impaired in bzip63 mutants. This study highlights a positive developmental function of SnRK1. During energy limitation, LRs are initiated and primed for outgrowth upon recovery. Hence, this study provides mechanistic insights into how energy shapes the agronomically important root system.
Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis. Lehmann, J.; Jorgensen, M. E.; Fratz, S.; Muller, H. M.; Kusch, J.; Scherzer, S.; Navarro-Retamal, C.; Mayer, D.; Bohm, J.; Konrad, K. R.; Terpitz, U.; Dreyer, I.; Mueller, T. D.; Sauer, M.; Hedrich, R.; Geiger, D.; Maierhofer, T. In Curr Biol, 31(16), pp. 3575–3585 e9. 2021.
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Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance.

@article{lehmann2021acidosisinduced, abstract = {Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance.}, author = {Lehmann, J. and Jorgensen, M. E. and Fratz, S. and Muller, H. M. and Kusch, J. and Scherzer, S. and Navarro-Retamal, C. and Mayer, D. and Bohm, J. and Konrad, K. R. and Terpitz, U. and Dreyer, I. and Mueller, T. D. and Sauer, M. and Hedrich, R. and Geiger, D. and Maierhofer, T.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Lehmann, Julian Jorgensen, Morten E Fratz, Stefanie Muller, Heike M Kusch, Jana Scherzer, Sonke Navarro-Retamal, Carlos Mayer, Dominik Bohm, Jennifer Konrad, Kai R Terpitz, Ulrich Dreyer, Ingo Mueller, Thomas D Sauer, Markus Hedrich, Rainer Geiger, Dietmar Maierhofer, Tobias eng Research Support, Non-U.S. Gov't England 2021/07/08 Curr Biol. 2021 Aug 23;31(16):3575-3585.e9. doi: 10.1016/j.cub.2021.06.018. Epub 2021 Jul 6.}, number = 16, pages = {3575-3585 e9}, title = {Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis}, type = {Journal Article}, volume = 31, year = 2021 }

%0 Journal Article %1 lehmann2021acidosisinduced %A Lehmann, J. %A Jorgensen, M. E. %A Fratz, S. %A Muller, H. M. %A Kusch, J. %A Scherzer, S. %A Navarro-Retamal, C. %A Mayer, D. %A Bohm, J. %A Konrad, K. R. %A Terpitz, U. %A Dreyer, I. %A Mueller, T. D. %A Sauer, M. %A Hedrich, R. %A Geiger, D. %A Maierhofer, T. %D 2021 %J Curr Biol %N 16 %P 3575-3585 e9 %R 10.1016/j.cub.2021.06.018 %T Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis %U https://www.ncbi.nlm.nih.gov/pubmed/34233161 %V 31 %X Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance.
Optogenetic control of the guard cell membrane potential and stomatal movement by the light-gated anion channel GtACR1. Huang, S.; Ding, M.; Roelfsema, M. R. G.; Dreyer, I.; Scherzer, S.; Al-Rasheid, K. A. S.; Gao, S.; Nagel, G.; Hedrich, R.; Konrad, K. R. In Sci Adv, 7(28). 2021.
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Guard cells control the aperture of plant stomata, which are crucial for global fluxes of CO(2) and water. In turn, guard cell anion channels are seen as key players for stomatal closure, but is activation of these channels sufficient to limit plant water loss? To answer this open question, we used an optogenetic approach based on the light-gated anion channelrhodopsin 1 (GtACR1). In tobacco guard cells that express GtACR1, blue- and green-light pulses elicit Cl(-) and NO(3) (-) currents of -1 to -2 nA. The anion currents depolarize the plasma membrane by 60 to 80 mV, which causes opening of voltage-gated K(+) channels and the extrusion of K(+) As a result, continuous stimulation with green light leads to loss of guard cell turgor and closure of stomata at conditions that provoke stomatal opening in wild type. GtACR1 optogenetics thus provides unequivocal evidence that opening of anion channels is sufficient to close stomata.

@article{huang2021optogenetic, abstract = {Guard cells control the aperture of plant stomata, which are crucial for global fluxes of CO(2) and water. In turn, guard cell anion channels are seen as key players for stomatal closure, but is activation of these channels sufficient to limit plant water loss? To answer this open question, we used an optogenetic approach based on the light-gated anion channelrhodopsin 1 (GtACR1). In tobacco guard cells that express GtACR1, blue- and green-light pulses elicit Cl(-) and NO(3) (-) currents of -1 to -2 nA. The anion currents depolarize the plasma membrane by 60 to 80 mV, which causes opening of voltage-gated K(+) channels and the extrusion of K(+) As a result, continuous stimulation with green light leads to loss of guard cell turgor and closure of stomata at conditions that provoke stomatal opening in wild type. GtACR1 optogenetics thus provides unequivocal evidence that opening of anion channels is sufficient to close stomata.}, author = {Huang, S. and Ding, M. and Roelfsema, M. R. G. and Dreyer, I. and Scherzer, S. and Al-Rasheid, K. A. S. and Gao, S. and Nagel, G. and Hedrich, R. and Konrad, K. R.}, journal = {Sci Adv}, keywords = {uni_network}, note = {Huang, Shouguang Ding, Meiqi Roelfsema, M Rob G Dreyer, Ingo Scherzer, Sonke Al-Rasheid, Khaled A S Gao, Shiqiang Nagel, Georg Hedrich, Rainer Konrad, Kai R eng 2021/07/11 Sci Adv. 2021 Jul 9;7(28):eabg4619. doi: 10.1126/sciadv.abg4619. Print 2021 Jul.}, number = 28, title = {Optogenetic control of the guard cell membrane potential and stomatal movement by the light-gated anion channel GtACR1}, type = {Journal Article}, volume = 7, year = 2021 }

%0 Journal Article %1 huang2021optogenetic %A Huang, S. %A Ding, M. %A Roelfsema, M. R. G. %A Dreyer, I. %A Scherzer, S. %A Al-Rasheid, K. A. S. %A Gao, S. %A Nagel, G. %A Hedrich, R. %A Konrad, K. R. %D 2021 %J Sci Adv %N 28 %R 10.1126/sciadv.abg4619 %T Optogenetic control of the guard cell membrane potential and stomatal movement by the light-gated anion channel GtACR1 %U https://www.ncbi.nlm.nih.gov/pubmed/34244145https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8270491/pdf/abg4619.pdf %V 7 %X Guard cells control the aperture of plant stomata, which are crucial for global fluxes of CO(2) and water. In turn, guard cell anion channels are seen as key players for stomatal closure, but is activation of these channels sufficient to limit plant water loss? To answer this open question, we used an optogenetic approach based on the light-gated anion channelrhodopsin 1 (GtACR1). In tobacco guard cells that express GtACR1, blue- and green-light pulses elicit Cl(-) and NO(3) (-) currents of -1 to -2 nA. The anion currents depolarize the plasma membrane by 60 to 80 mV, which causes opening of voltage-gated K(+) channels and the extrusion of K(+) As a result, continuous stimulation with green light leads to loss of guard cell turgor and closure of stomata at conditions that provoke stomatal opening in wild type. GtACR1 optogenetics thus provides unequivocal evidence that opening of anion channels is sufficient to close stomata.
Under salt stress guard cells rewire ion transport and abscisic acid signaling. Karimi, S. M.; Freund, M.; Wager, B. M.; Knoblauch, M.; Fromm, J.; H, M. Mueller; Ache, P.; Krischke, M.; Mueller, M. J.; Muller, T.; Dittrich, M.; Geilfus, C. M.; Alfarhan, A. H.; Hedrich, R.; Deeken, R. In New Phytol, 231(3), pp. 1040–1055. 2021.
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Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.

@article{karimi2021under, abstract = {Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.}, author = {Karimi, S. M. and Freund, M. and Wager, B. M. and Knoblauch, M. and Fromm, J. and H, M. Mueller and Ache, P. and Krischke, M. and Mueller, M. J. and Muller, T. and Dittrich, M. and Geilfus, C. M. and Alfarhan, A. H. and Hedrich, R. and Deeken, R.}, journal = {New Phytol}, keywords = {uni_network}, note = {Karimi, Sohail M Freund, Matthias Wager, Brittney M Knoblauch, Michael Fromm, Jorg M Mueller, Heike Ache, Peter Krischke, Markus Mueller, Martin J Muller, Tobias Dittrich, Marcus Geilfus, Christoph-Martin Alfarhan, Ahmed H Hedrich, Rainer Deeken, Rosalia eng Research Support, Non-U.S. Gov't England 2021/03/29 New Phytol. 2021 Aug;231(3):1040-1055. doi: 10.1111/nph.17376. Epub 2021 Jun 16.}, number = 3, pages = {1040-1055}, title = {Under salt stress guard cells rewire ion transport and abscisic acid signaling}, type = {Journal Article}, volume = 231, year = 2021 }

%0 Journal Article %1 karimi2021under %A Karimi, S. M. %A Freund, M. %A Wager, B. M. %A Knoblauch, M. %A Fromm, J. %A H, M. Mueller %A Ache, P. %A Krischke, M. %A Mueller, M. J. %A Muller, T. %A Dittrich, M. %A Geilfus, C. M. %A Alfarhan, A. H. %A Hedrich, R. %A Deeken, R. %D 2021 %J New Phytol %N 3 %P 1040-1055 %R 10.1111/nph.17376 %T Under salt stress guard cells rewire ion transport and abscisic acid signaling %U https://www.ncbi.nlm.nih.gov/pubmed/33774818 %V 231 %X Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity.

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Metabolomic profiling and anti-infective potential of Zinnia elegans and Gazania rigens (Family Asteraceae). Gomaa, A. A.; Samy, M. N.; Abdelmohsen, U. R.; Krischke, M.; Mueller, M. J.; Wanas, A. S.; Desoukey, S. Y.; Kamel, M. S. In Nat Prod Res, 34(18), pp. 2612–2615. 2020.
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The present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC-HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC(50) values of 21.03 and 13.72 microg/mL against Plasmodium falciparum D(6) and P. falciparum W(2), respectively.

@article{gomaa2020metabolomic, abstract = {The present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC-HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC(50) values of 21.03 and 13.72 microg/mL against Plasmodium falciparum D(6) and P. falciparum W(2), respectively.}, author = {Gomaa, A. A. and Samy, M. N. and Abdelmohsen, U. R. and Krischke, M. and Mueller, M. J. and Wanas, A. S. and Desoukey, S. Y. and Kamel, M. S.}, journal = {Nat Prod Res}, keywords = {Agents/*isolation}, note = {Gomaa, Alshymaa Abdel-Rahman Samy, Mamdouh Nabil Abdelmohsen, Usama Ramadan Krischke, Markus Mueller, Martin J Wanas, Amira Samir Desoukey, Samar Yehia Kamel, Mohamed Salah eng England 2018/12/26 Nat Prod Res. 2020 Sep;34(18):2612-2615. doi: 10.1080/14786419.2018.1544975. Epub 2018 Dec 22.}, number = 18, pages = {2612-2615}, title = {Metabolomic profiling and anti-infective potential of Zinnia elegans and Gazania rigens (Family Asteraceae)}, type = {Journal Article}, volume = 34, year = 2020 }

%0 Journal Article %1 gomaa2020metabolomic %A Gomaa, A. A. %A Samy, M. N. %A Abdelmohsen, U. R. %A Krischke, M. %A Mueller, M. J. %A Wanas, A. S. %A Desoukey, S. Y. %A Kamel, M. S. %D 2020 %J Nat Prod Res %N 18 %P 2612-2615 %R 10.1080/14786419.2018.1544975 %T Metabolomic profiling and anti-infective potential of Zinnia elegans and Gazania rigens (Family Asteraceae) %U https://www.ncbi.nlm.nih.gov/pubmed/30580583 %V 34 %X The present study evaluates the chemical composition of Zinnia elegans and Gazania rigens based on their metabolomic profiles using liquid chromatography coupled with high-resolution mass spectrometry (LC-HR-MS), alongside with the anti-infective activities of their ethanol extracts, as well as, different fractions. A significant difference was observed between the LC-MS profiles of the two plants such as, coumarins, sesquiterpene lactones and phenylethanoids which were characteristic for Z. elegans, while amides and phenolic acid derivatives were characteristic for G. rigens. These results highlight the chemical potential of Z. elegans and G. rigens. Furthermore, the ethyl acetate fraction of Z. elegans showed a significant antimalarial activity with IC(50) values of 21.03 and 13.72 microg/mL against Plasmodium falciparum D(6) and P. falciparum W(2), respectively.
Targeting interleukin-4 to the arthritic joint. Spieler, V.; Ludwig, M. G.; Dawson, J.; Tigani, B.; Littlewood-Evans, A.; Safina, C.; Ebersbach, H.; Seuwen, K.; Raschig, M.; Ter Mors, B.; Muller, T. D.; Meinel, L.; Luhmann, T. In J Control Release, 326, pp. 172–180. 2020.
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Anti-inflammatory cytokines are a promising class of therapeutics for treatment of rheumatoid arthritis (RA), but their use is currently limited by a rapid clearance and systemic toxicity. Interleukin-4 is a small cytokine with potential for RA therapy. To increase its pharmacokinetic features, we engineered a murine IL4 conjugate by incorporating an unnatural amino acid through genetic code expansion to which PEG-folate, as a targeting moiety and PEG alone as control, were site-specifically bound. Both IL4 conjugates retained bioactivity and induced primary murine macrophage polarization into an alternatively activated (M2) related phenotype. The PEGylated conjugates had a terminal half-life of about four hours in healthy mice compared to unPEGylated IL4 (0.76 h). We showed that both conjugates successfully accumulated into arthritic joints in an antigen-induced arthritis (AIA) mouse model, as assessed by non-invasive fluorescence imaging. The modular nature of the IL4 conjugate chemistry presented herein facilitates easy adaption of PEG chain length and targeting moieties for further improvement of half-life and targeting function for future efficacy studies.

@article{spieler2020targeting, abstract = {Anti-inflammatory cytokines are a promising class of therapeutics for treatment of rheumatoid arthritis (RA), but their use is currently limited by a rapid clearance and systemic toxicity. Interleukin-4 is a small cytokine with potential for RA therapy. To increase its pharmacokinetic features, we engineered a murine IL4 conjugate by incorporating an unnatural amino acid through genetic code expansion to which PEG-folate, as a targeting moiety and PEG alone as control, were site-specifically bound. Both IL4 conjugates retained bioactivity and induced primary murine macrophage polarization into an alternatively activated (M2) related phenotype. The PEGylated conjugates had a terminal half-life of about four hours in healthy mice compared to unPEGylated IL4 (0.76 h). We showed that both conjugates successfully accumulated into arthritic joints in an antigen-induced arthritis (AIA) mouse model, as assessed by non-invasive fluorescence imaging. The modular nature of the IL4 conjugate chemistry presented herein facilitates easy adaption of PEG chain length and targeting moieties for further improvement of half-life and targeting function for future efficacy studies.}, author = {Spieler, V. and Ludwig, M. G. and Dawson, J. and Tigani, B. and Littlewood-Evans, A. and Safina, C. and Ebersbach, H. and Seuwen, K. and Raschig, M. and Ter Mors, B. and Muller, T. D. and Meinel, L. and Luhmann, T.}, journal = {J Control Release}, keywords = {Amino}, note = {Spieler, Valerie Ludwig, Marie-Gabrielle Dawson, Janet Tigani, Bruno Littlewood-Evans, Amanda Safina, Caterina Ebersbach, Hilmar Seuwen, Klaus Raschig, Martina Ter Mors, Bjorn Muller, Thomas D Meinel, Lorenz Luhmann, Tessa eng Research Support, Non-U.S. Gov't Netherlands 2020/07/13 J Control Release. 2020 Oct 10;326:172-180. doi: 10.1016/j.jconrel.2020.07.005. Epub 2020 Jul 10.}, pages = {172-180}, title = {Targeting interleukin-4 to the arthritic joint}, type = {Journal Article}, volume = 326, year = 2020 }

%0 Journal Article %1 spieler2020targeting %A Spieler, V. %A Ludwig, M. G. %A Dawson, J. %A Tigani, B. %A Littlewood-Evans, A. %A Safina, C. %A Ebersbach, H. %A Seuwen, K. %A Raschig, M. %A Ter Mors, B. %A Muller, T. D. %A Meinel, L. %A Luhmann, T. %D 2020 %J J Control Release %P 172-180 %R 10.1016/j.jconrel.2020.07.005 %T Targeting interleukin-4 to the arthritic joint %U https://www.ncbi.nlm.nih.gov/pubmed/32653504 %V 326 %X Anti-inflammatory cytokines are a promising class of therapeutics for treatment of rheumatoid arthritis (RA), but their use is currently limited by a rapid clearance and systemic toxicity. Interleukin-4 is a small cytokine with potential for RA therapy. To increase its pharmacokinetic features, we engineered a murine IL4 conjugate by incorporating an unnatural amino acid through genetic code expansion to which PEG-folate, as a targeting moiety and PEG alone as control, were site-specifically bound. Both IL4 conjugates retained bioactivity and induced primary murine macrophage polarization into an alternatively activated (M2) related phenotype. The PEGylated conjugates had a terminal half-life of about four hours in healthy mice compared to unPEGylated IL4 (0.76 h). We showed that both conjugates successfully accumulated into arthritic joints in an antigen-induced arthritis (AIA) mouse model, as assessed by non-invasive fluorescence imaging. The modular nature of the IL4 conjugate chemistry presented herein facilitates easy adaption of PEG chain length and targeting moieties for further improvement of half-life and targeting function for future efficacy studies.
An improved growth medium for enhanced inoculum production of the plant growth-promoting fungus Serendipita indica. Osman, M.; Stigloher, C.; Mueller, M. J.; Waller, F. In Plant Methods, 16, p. 39. 2020.
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BACKGROUND: The plant endophytic fungus Serendipita indica colonizes roots of a wide range of plant species and can enhance growth and stress resistance of these plants. Due to its ease of axenic cultivation and its broad host plant range including the model plant Arabidopsis thaliana and numerous crop plants, it is widely used as a model fungus to study beneficial fungus-root interactions. In addition, it was suggested to be utilized for commercial applications, e.g. to enhance yield in barley and other species. To produce inoculum, S. indica is mostly cultivated in a complex Hill-Kafer medium (CM medium), however, growth in this medium is slow, and yield of chlamydospores, which are often used for plant root inoculation, is relatively low. RESULTS: We tested and optimized a simple vegetable juice-based medium for an enhanced yield of fungal inoculum. The described vegetable juice (VJ) medium is based on commercially available vegetable juice and is easy to prepare. VJ medium was superior to the currently used CM medium with respect to biomass production in liquid medium and hyphal growth on agar plates. Using solid VJ medium supplemented with sucrose (VJS), a high amount of chlamydospores developed already after 8 days of cultivation, producing significantly more spores than on CM medium. Use of VJ medium is not restricted to S. indica, as it also supported growth of two pathogenic fungi often used in plant pathology experiments: the ascomycete Fusarium graminearum, the causal agent of Fusarium head blight disease on wheat and barley, and Verticillium longisporum, the causal agent of verticillium wilt. CONCLUSIONS: The described VJ medium is recommended for streamlined and efficient production of inoculum for the plant endophytic fungus Serendipita indica and might prove superior for the propagation of other fungi for research purposes.

@article{osman2020improved, abstract = {BACKGROUND: The plant endophytic fungus Serendipita indica colonizes roots of a wide range of plant species and can enhance growth and stress resistance of these plants. Due to its ease of axenic cultivation and its broad host plant range including the model plant Arabidopsis thaliana and numerous crop plants, it is widely used as a model fungus to study beneficial fungus-root interactions. In addition, it was suggested to be utilized for commercial applications, e.g. to enhance yield in barley and other species. To produce inoculum, S. indica is mostly cultivated in a complex Hill-Kafer medium (CM medium), however, growth in this medium is slow, and yield of chlamydospores, which are often used for plant root inoculation, is relatively low. RESULTS: We tested and optimized a simple vegetable juice-based medium for an enhanced yield of fungal inoculum. The described vegetable juice (VJ) medium is based on commercially available vegetable juice and is easy to prepare. VJ medium was superior to the currently used CM medium with respect to biomass production in liquid medium and hyphal growth on agar plates. Using solid VJ medium supplemented with sucrose (VJS), a high amount of chlamydospores developed already after 8 days of cultivation, producing significantly more spores than on CM medium. Use of VJ medium is not restricted to S. indica, as it also supported growth of two pathogenic fungi often used in plant pathology experiments: the ascomycete Fusarium graminearum, the causal agent of Fusarium head blight disease on wheat and barley, and Verticillium longisporum, the causal agent of verticillium wilt. CONCLUSIONS: The described VJ medium is recommended for streamlined and efficient production of inoculum for the plant endophytic fungus Serendipita indica and might prove superior for the propagation of other fungi for research purposes.}, author = {Osman, M. and Stigloher, C. and Mueller, M. J. and Waller, F.}, journal = {Plant Methods}, keywords = {medium}, note = {Osman, Mohamed Stigloher, Christian Mueller, Martin J Waller, Frank eng England 2020/03/20 Plant Methods. 2020 Mar 16;16:39. doi: 10.1186/s13007-020-00584-7. eCollection 2020.}, pages = 39, title = {An improved growth medium for enhanced inoculum production of the plant growth-promoting fungus Serendipita indica}, type = {Journal Article}, volume = 16, year = 2020 }

%0 Journal Article %1 osman2020improved %A Osman, M. %A Stigloher, C. %A Mueller, M. J. %A Waller, F. %D 2020 %J Plant Methods %P 39 %R 10.1186/s13007-020-00584-7 %T An improved growth medium for enhanced inoculum production of the plant growth-promoting fungus Serendipita indica %U https://www.ncbi.nlm.nih.gov/pubmed/32190103https://plantmethods.biomedcentral.com/counter/pdf/10.1186/s13007-020-00584-7.pdf %V 16 %X BACKGROUND: The plant endophytic fungus Serendipita indica colonizes roots of a wide range of plant species and can enhance growth and stress resistance of these plants. Due to its ease of axenic cultivation and its broad host plant range including the model plant Arabidopsis thaliana and numerous crop plants, it is widely used as a model fungus to study beneficial fungus-root interactions. In addition, it was suggested to be utilized for commercial applications, e.g. to enhance yield in barley and other species. To produce inoculum, S. indica is mostly cultivated in a complex Hill-Kafer medium (CM medium), however, growth in this medium is slow, and yield of chlamydospores, which are often used for plant root inoculation, is relatively low. RESULTS: We tested and optimized a simple vegetable juice-based medium for an enhanced yield of fungal inoculum. The described vegetable juice (VJ) medium is based on commercially available vegetable juice and is easy to prepare. VJ medium was superior to the currently used CM medium with respect to biomass production in liquid medium and hyphal growth on agar plates. Using solid VJ medium supplemented with sucrose (VJS), a high amount of chlamydospores developed already after 8 days of cultivation, producing significantly more spores than on CM medium. Use of VJ medium is not restricted to S. indica, as it also supported growth of two pathogenic fungi often used in plant pathology experiments: the ascomycete Fusarium graminearum, the causal agent of Fusarium head blight disease on wheat and barley, and Verticillium longisporum, the causal agent of verticillium wilt. CONCLUSIONS: The described VJ medium is recommended for streamlined and efficient production of inoculum for the plant endophytic fungus Serendipita indica and might prove superior for the propagation of other fungi for research purposes.
Epichloe Endophyte Infection rates and Alkaloid Content in Commercially Available Grass Seed Mixtures in Europe. Krauss, J.; Vikuk, V.; Young, C. A.; Krischke, M.; Mueller, M. J.; Baerenfaller, K. In Microorganisms, 8(4). 2020.
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Fungal endophytes of the genus Epichloe live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloe infected grasses, the inclusion of Epichloe in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloe infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloe endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloe infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloe festucae var. lolii infecting Lolium perenne. As Epichloe infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloe infection status or avoiding Epichloe infected seed mixtures.

@article{krauss2020epichloe, abstract = {Fungal endophytes of the genus Epichloe live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloe infected grasses, the inclusion of Epichloe in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloe infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloe endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloe infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloe festucae var. lolii infecting Lolium perenne. As Epichloe infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloe infection status or avoiding Epichloe infected seed mixtures.}, author = {Krauss, J. and Vikuk, V. and Young, C. A. and Krischke, M. and Mueller, M. J. and Baerenfaller, K.}, journal = {Microorganisms}, keywords = {spp.}, note = {Krauss, Jochen Vikuk, Veronika Young, Carolyn A Krischke, Markus Mueller, Martin J Baerenfaller, Katja eng KR 3559/3-2/Deutsche Forschungsgemeinschaft/ Switzerland 2020/04/05 Microorganisms. 2020 Mar 31;8(4):498. doi: 10.3390/microorganisms8040498.}, number = 4, title = {Epichloe Endophyte Infection rates and Alkaloid Content in Commercially Available Grass Seed Mixtures in Europe}, type = {Journal Article}, volume = 8, year = 2020 }

%0 Journal Article %1 krauss2020epichloe %A Krauss, J. %A Vikuk, V. %A Young, C. A. %A Krischke, M. %A Mueller, M. J. %A Baerenfaller, K. %D 2020 %J Microorganisms %N 4 %R 10.3390/microorganisms8040498 %T Epichloe Endophyte Infection rates and Alkaloid Content in Commercially Available Grass Seed Mixtures in Europe %U https://www.ncbi.nlm.nih.gov/pubmed/32244510https://mdpi-res.com/d_attachment/microorganisms/microorganisms-08-00498/article_deploy/microorganisms-08-00498-v2.pdf?version=1585811170 %V 8 %X Fungal endophytes of the genus Epichloe live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloe infected grasses, the inclusion of Epichloe in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloe infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloe endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloe infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloe festucae var. lolii infecting Lolium perenne. As Epichloe infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloe infection status or avoiding Epichloe infected seed mixtures.
Genomes of the Venus Flytrap and Close Relatives Unveil the Roots of Plant Carnivory. Palfalvi, G.; Hackl, T.; Terhoeven, N.; Shibata, T. F.; Nishiyama, T.; Ankenbrand, M.; Becker, D.; Forster, F.; Freund, M.; Iosip, A.; Kreuzer, I.; Saul, F.; Kamida, C.; Fukushima, K.; Shigenobu, S.; Tamada, Y.; Adamec, L.; Hoshi, Y.; Ueda, K.; Winkelmann, T.; Fuchs, J.; Schubert, I.; Schwacke, R.; Al-Rasheid, K.; Schultz, J.; Hasebe, M.; Hedrich, R. In Curr Biol, 30(12), pp. 2312–2320 e5. 2020.
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Most plants grow and develop by taking up nutrients from the soil while continuously under threat from foraging animals. Carnivorous plants have turned the tables by capturing and consuming nutrient-rich animal prey, enabling them to thrive in nutrient-poor soil. To better understand the evolution of botanical carnivory, we compared the draft genome of the Venus flytrap (Dionaea muscipula) with that of its aquatic sister, the waterwheel plant Aldrovanda vesiculosa, and the sundew Drosera spatulata. We identified an early whole-genome duplication in the family as source for carnivory-associated genes. Recruitment of genes to the trap from the root especially was a major mechanism in the evolution of carnivory, supported by family-specific duplications. Still, these genomes belong to the gene poorest land plants sequenced thus far, suggesting reduction of selective pressure on different processes, including non-carnivorous nutrient acquisition. Our results show how non-carnivorous plants evolved into the most skillful green hunters on the planet.

@article{palfalvi2020genomes, abstract = {Most plants grow and develop by taking up nutrients from the soil while continuously under threat from foraging animals. Carnivorous plants have turned the tables by capturing and consuming nutrient-rich animal prey, enabling them to thrive in nutrient-poor soil. To better understand the evolution of botanical carnivory, we compared the draft genome of the Venus flytrap (Dionaea muscipula) with that of its aquatic sister, the waterwheel plant Aldrovanda vesiculosa, and the sundew Drosera spatulata. We identified an early whole-genome duplication in the family as source for carnivory-associated genes. Recruitment of genes to the trap from the root especially was a major mechanism in the evolution of carnivory, supported by family-specific duplications. Still, these genomes belong to the gene poorest land plants sequenced thus far, suggesting reduction of selective pressure on different processes, including non-carnivorous nutrient acquisition. Our results show how non-carnivorous plants evolved into the most skillful green hunters on the planet.}, author = {Palfalvi, G. and Hackl, T. and Terhoeven, N. and Shibata, T. F. and Nishiyama, T. and Ankenbrand, M. and Becker, D. and Forster, F. and Freund, M. and Iosip, A. and Kreuzer, I. and Saul, F. and Kamida, C. and Fukushima, K. and Shigenobu, S. and Tamada, Y. and Adamec, L. and Hoshi, Y. and Ueda, K. and Winkelmann, T. and Fuchs, J. and Schubert, I. and Schwacke, R. and Al-Rasheid, K. and Schultz, J. and Hasebe, M. and Hedrich, R.}, journal = {Curr Biol}, keywords = {*Biological}, note = {Palfalvi, Gergo Hackl, Thomas Terhoeven, Niklas Shibata, Tomoko F Nishiyama, Tomoaki Ankenbrand, Markus Becker, Dirk Forster, Frank Freund, Matthias Iosip, Anda Kreuzer, Ines Saul, Franziska Kamida, Chiharu Fukushima, Kenji Shigenobu, Shuji Tamada, Yosuke Adamec, Lubomir Hoshi, Yoshikazu Ueda, Kunihiko Winkelmann, Traud Fuchs, Jorg Schubert, Ingo Schwacke, Rainer Al-Rasheid, Khaled Schultz, Jorg Hasebe, Mitsuyasu Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2020/05/16 Curr Biol. 2020 Jun 22;30(12):2312-2320.e5. doi: 10.1016/j.cub.2020.04.051. Epub 2020 May 14.}, number = 12, pages = {2312-2320 e5}, title = {Genomes of the Venus Flytrap and Close Relatives Unveil the Roots of Plant Carnivory}, type = {Journal Article}, volume = 30, year = 2020 }

%0 Journal Article %1 palfalvi2020genomes %A Palfalvi, G. %A Hackl, T. %A Terhoeven, N. %A Shibata, T. F. %A Nishiyama, T. %A Ankenbrand, M. %A Becker, D. %A Forster, F. %A Freund, M. %A Iosip, A. %A Kreuzer, I. %A Saul, F. %A Kamida, C. %A Fukushima, K. %A Shigenobu, S. %A Tamada, Y. %A Adamec, L. %A Hoshi, Y. %A Ueda, K. %A Winkelmann, T. %A Fuchs, J. %A Schubert, I. %A Schwacke, R. %A Al-Rasheid, K. %A Schultz, J. %A Hasebe, M. %A Hedrich, R. %D 2020 %J Curr Biol %N 12 %P 2312-2320 e5 %R 10.1016/j.cub.2020.04.051 %T Genomes of the Venus Flytrap and Close Relatives Unveil the Roots of Plant Carnivory %U https://www.ncbi.nlm.nih.gov/pubmed/32413308 %V 30 %X Most plants grow and develop by taking up nutrients from the soil while continuously under threat from foraging animals. Carnivorous plants have turned the tables by capturing and consuming nutrient-rich animal prey, enabling them to thrive in nutrient-poor soil. To better understand the evolution of botanical carnivory, we compared the draft genome of the Venus flytrap (Dionaea muscipula) with that of its aquatic sister, the waterwheel plant Aldrovanda vesiculosa, and the sundew Drosera spatulata. We identified an early whole-genome duplication in the family as source for carnivory-associated genes. Recruitment of genes to the trap from the root especially was a major mechanism in the evolution of carnivory, supported by family-specific duplications. Still, these genomes belong to the gene poorest land plants sequenced thus far, suggesting reduction of selective pressure on different processes, including non-carnivorous nutrient acquisition. Our results show how non-carnivorous plants evolved into the most skillful green hunters on the planet.
The MscS-like channel YnaI has a gating mechanism based on flexible pore helices. Flegler, V. J.; Rasmussen, A.; Rao, S.; Wu, N.; Zenobi, R.; Sansom, M. S. P.; Hedrich, R.; Rasmussen, T.; Bottcher, B. In Proc Natl Acad Sci U S A, 117(46), pp. 28754–28762. 2020.
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The mechanosensitive channel of small conductance (MscS) is the prototype of an evolutionarily diversified large family that fine-tunes osmoregulation but is likely to fulfill additional functions. Escherichia coli has six osmoprotective paralogs with different numbers of transmembrane helices. These helices are important for gating and sensing in MscS but the role of the additional helices in the paralogs is not understood. The medium-sized channel YnaI was extracted and delivered in native nanodiscs in closed-like and open-like conformations using the copolymer diisobutylene/maleic acid (DIBMA) for structural studies. Here we show by electron cryomicroscopy that YnaI has an extended sensor paddle that during gating relocates relative to the pore concomitant with bending of a GGxGG motif in the pore helices. YnaI is the only one of the six paralogs that has this GGxGG motif allowing the sensor paddle to move outward. Access to the pore is through a vestibule on the cytosolic side that is fenestrated by side portals. In YnaI, these portals are obstructed by aromatic side chains but are still fully hydrated and thus support conductance. For comparison with large-sized channels, we determined the structure of YbiO, which showed larger portals and a wider pore with no GGxGG motif. Further in silico comparison of MscS, YnaI, and YbiO highlighted differences in the hydrophobicity and wettability of their pores and vestibule interiors. Thus, MscS-like channels of different sizes have a common core architecture but show different gating mechanisms and fine-tuned conductive properties.

@article{flegler2020mscslike, abstract = {The mechanosensitive channel of small conductance (MscS) is the prototype of an evolutionarily diversified large family that fine-tunes osmoregulation but is likely to fulfill additional functions. Escherichia coli has six osmoprotective paralogs with different numbers of transmembrane helices. These helices are important for gating and sensing in MscS but the role of the additional helices in the paralogs is not understood. The medium-sized channel YnaI was extracted and delivered in native nanodiscs in closed-like and open-like conformations using the copolymer diisobutylene/maleic acid (DIBMA) for structural studies. Here we show by electron cryomicroscopy that YnaI has an extended sensor paddle that during gating relocates relative to the pore concomitant with bending of a GGxGG motif in the pore helices. YnaI is the only one of the six paralogs that has this GGxGG motif allowing the sensor paddle to move outward. Access to the pore is through a vestibule on the cytosolic side that is fenestrated by side portals. In YnaI, these portals are obstructed by aromatic side chains but are still fully hydrated and thus support conductance. For comparison with large-sized channels, we determined the structure of YbiO, which showed larger portals and a wider pore with no GGxGG motif. Further in silico comparison of MscS, YnaI, and YbiO highlighted differences in the hydrophobicity and wettability of their pores and vestibule interiors. Thus, MscS-like channels of different sizes have a common core architecture but show different gating mechanisms and fine-tuned conductive properties.}, author = {Flegler, V. J. and Rasmussen, A. and Rao, S. and Wu, N. and Zenobi, R. and Sansom, M. S. P. and Hedrich, R. and Rasmussen, T. and Bottcher, B.}, journal = {Proc Natl Acad Sci U S A}, keywords = {uni_network}, note = {Flegler, Vanessa Judith Rasmussen, Akiko Rao, Shanlin Wu, Na Zenobi, Renato Sansom, Mark S P Hedrich, Rainer Rasmussen, Tim Bottcher, Bettina eng WT_/Wellcome Trust/United Kingdom 208361/Z/17/Z/WT_/Wellcome Trust/United Kingdom BB/N000145/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom Research Support, Non-U.S. Gov't 2020/11/06 Proc Natl Acad Sci U S A. 2020 Nov 17;117(46):28754-28762. doi: 10.1073/pnas.2005641117. Epub 2020 Nov 4.}, number = 46, pages = {28754-28762}, title = {The MscS-like channel YnaI has a gating mechanism based on flexible pore helices}, type = {Journal Article}, volume = 117, year = 2020 }

%0 Journal Article %1 flegler2020mscslike %A Flegler, V. J. %A Rasmussen, A. %A Rao, S. %A Wu, N. %A Zenobi, R. %A Sansom, M. S. P. %A Hedrich, R. %A Rasmussen, T. %A Bottcher, B. %D 2020 %J Proc Natl Acad Sci U S A %N 46 %P 28754-28762 %R 10.1073/pnas.2005641117 %T The MscS-like channel YnaI has a gating mechanism based on flexible pore helices %U https://www.ncbi.nlm.nih.gov/pubmed/33148804https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7682570/pdf/pnas.202005641.pdf %V 117 %X The mechanosensitive channel of small conductance (MscS) is the prototype of an evolutionarily diversified large family that fine-tunes osmoregulation but is likely to fulfill additional functions. Escherichia coli has six osmoprotective paralogs with different numbers of transmembrane helices. These helices are important for gating and sensing in MscS but the role of the additional helices in the paralogs is not understood. The medium-sized channel YnaI was extracted and delivered in native nanodiscs in closed-like and open-like conformations using the copolymer diisobutylene/maleic acid (DIBMA) for structural studies. Here we show by electron cryomicroscopy that YnaI has an extended sensor paddle that during gating relocates relative to the pore concomitant with bending of a GGxGG motif in the pore helices. YnaI is the only one of the six paralogs that has this GGxGG motif allowing the sensor paddle to move outward. Access to the pore is through a vestibule on the cytosolic side that is fenestrated by side portals. In YnaI, these portals are obstructed by aromatic side chains but are still fully hydrated and thus support conductance. For comparison with large-sized channels, we determined the structure of YbiO, which showed larger portals and a wider pore with no GGxGG motif. Further in silico comparison of MscS, YnaI, and YbiO highlighted differences in the hydrophobicity and wettability of their pores and vestibule interiors. Thus, MscS-like channels of different sizes have a common core architecture but show different gating mechanisms and fine-tuned conductive properties.
An Activating Deletion Variant in the Submembrane Region of Natriuretic Peptide Receptor-B Causes Tall Stature. Lauffer, P.; Miranda-Laferte, E.; van Duyvenvoorde, H. A.; van Haeringen, A.; Werner, F.; Boudin, E.; Schmidt, H.; Mueller, T. D.; Kuhn, M.; van der Kaay, D. C. M. In J Clin Endocrinol Metab, 105(7), pp. 2354–66. 2020.
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CONTEXT: C-type natriuretic peptide (CNP) is critically involved in endochondral bone growth. Variants in the genes encoding CNP or its cyclic guanosine monophosphate (cGMP)-forming receptor (natriuretic peptide receptor-B [NPR-B], gene NPR2) cause monogenic growth disorders. Here we describe a novel gain-of-function variant of NPR-B associated with tall stature and macrodactyly of the great toes (epiphyseal chondrodysplasia, Miura type). DESIGN: History and clinical characteristics of 3 family members were collected. NPR2 was selected for sequencing. Skin fibroblasts and transfected HEK-293 cells were used to compare mutant versus wild-type NPR-B activities. Homology modeling was applied to understand the molecular consequences of the variant. RESULTS: Mother's height was +2.77 standard deviation scores (SDS). The heights of her 2 daughters were +1.96 SDS at 7 years and +1.30 SDS at 4 years of age. Skeletal surveys showed macrodactyly of the great toes and pseudo-epiphyses of the mid- and proximal phalanges. Sequencing identified a novel heterozygous variant c.1444_1449delATGCTG in exon 8 of NPR2, predicted to result in deletion of 2 amino acids Met482-Leu483 within the submembrane region of NPR-B. In proband's skin fibroblasts, basal cGMP levels and CNP-stimulated cGMP production were markedly increased compared with controls. Consistently, assays with transfected HEK-293 cells showed markedly augmented baseline and ligand-dependent activity of mutant NPR-B. CONCLUSIONS: We report the second activating variant within the intracellular submembrane region of NPR-B resulting in tall stature and macrodactyly. Our functional and modeling studies suggest that this domain plays a critical role in the baseline conformation and ligand-dependent structural rearrangement of NPR-B required for cGMP production.

@article{lauffer2020activating, abstract = {CONTEXT: C-type natriuretic peptide (CNP) is critically involved in endochondral bone growth. Variants in the genes encoding CNP or its cyclic guanosine monophosphate (cGMP)-forming receptor (natriuretic peptide receptor-B [NPR-B], gene NPR2) cause monogenic growth disorders. Here we describe a novel gain-of-function variant of NPR-B associated with tall stature and macrodactyly of the great toes (epiphyseal chondrodysplasia, Miura type). DESIGN: History and clinical characteristics of 3 family members were collected. NPR2 was selected for sequencing. Skin fibroblasts and transfected HEK-293 cells were used to compare mutant versus wild-type NPR-B activities. Homology modeling was applied to understand the molecular consequences of the variant. RESULTS: Mother's height was +2.77 standard deviation scores (SDS). The heights of her 2 daughters were +1.96 SDS at 7 years and +1.30 SDS at 4 years of age. Skeletal surveys showed macrodactyly of the great toes and pseudo-epiphyses of the mid- and proximal phalanges. Sequencing identified a novel heterozygous variant c.1444_1449delATGCTG in exon 8 of NPR2, predicted to result in deletion of 2 amino acids Met482-Leu483 within the submembrane region of NPR-B. In proband's skin fibroblasts, basal cGMP levels and CNP-stimulated cGMP production were markedly increased compared with controls. Consistently, assays with transfected HEK-293 cells showed markedly augmented baseline and ligand-dependent activity of mutant NPR-B. CONCLUSIONS: We report the second activating variant within the intracellular submembrane region of NPR-B resulting in tall stature and macrodactyly. Our functional and modeling studies suggest that this domain plays a critical role in the baseline conformation and ligand-dependent structural rearrangement of NPR-B required for cGMP production.}, author = {Lauffer, P. and Miranda-Laferte, E. and van Duyvenvoorde, H. A. and van Haeringen, A. and Werner, F. and Boudin, E. and Schmidt, H. and Mueller, T. D. and Kuhn, M. and van der Kaay, D. C. M.}, journal = {J Clin Endocrinol Metab}, keywords = {Adult}, note = {Lauffer, Peter Miranda-Laferte, Erick van Duyvenvoorde, Hermine A van Haeringen, Arie Werner, Franziska Boudin, Eveline Schmidt, Hannes Mueller, Thomas D Kuhn, Michaela van der Kaay, Danielle C M eng Case Reports Research Support, Non-U.S. Gov't 2020/04/14 J Clin Endocrinol Metab. 2020 Jul 1;105(7):2354-66. doi: 10.1210/clinem/dgaa190.}, number = 7, pages = {2354-66}, title = {An Activating Deletion Variant in the Submembrane Region of Natriuretic Peptide Receptor-B Causes Tall Stature}, type = {Journal Article}, volume = 105, year = 2020 }

%0 Journal Article %1 lauffer2020activating %A Lauffer, P. %A Miranda-Laferte, E. %A van Duyvenvoorde, H. A. %A van Haeringen, A. %A Werner, F. %A Boudin, E. %A Schmidt, H. %A Mueller, T. D. %A Kuhn, M. %A van der Kaay, D. C. M. %D 2020 %J J Clin Endocrinol Metab %N 7 %P 2354-66 %R 10.1210/clinem/dgaa190 %T An Activating Deletion Variant in the Submembrane Region of Natriuretic Peptide Receptor-B Causes Tall Stature %U https://www.ncbi.nlm.nih.gov/pubmed/32282051https://watermark.silverchair.com/dgaa190.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAA1UwggNRBgkqhkiG9w0BBwagggNCMIIDPgIBADCCAzcGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMYbNWbhaARt8AzI-GAgEQgIIDCBWo33Lx4pJ3hgvtEeqU37MKrMS8fjjXELxC_Hp2nkCoDZKFrOyEdLEh-NrHM0liJ3eG9ZZ6_h1rmudvEo0b8UU50lKtFng5LmwarKLQ3cSYpw7N6OgqlnWwb0QV1u6OOY4eYAMAENrJb3q-UEgGPHMRaKrwhH2NhS0ypvlMq4gCpLBZE00wymBYflQ1pawGep-wr50lUlrsnBu-dPE_WXI_wzj_4ZiRdxFVSlICIyJdSS7z89_HD4GUO89EEb6s9RTWXFeNtyPW7yzZ8ndc2IKZq-pHovUehgDFPeMKBgjxr13uy3q94pkCxF6A34m-3CVBwGExSgrroBNfQ11YpbRKmOsiwU3R6-gjF7HJUIU4E1Wny_KgwZk2RGs6AGzsK8yHL2X3U2-oCRlU3ldawGDDJ6ekiU4kBSPqo3BVEqQlToNSYVXD0beIhGG4BvRo7_p_MYfmW9-oj1bY1GpsvLS76uvpDDKtPhQAm0BpKmrC-pQqn3O-M6gvmRnfbpIRMwpUUeTiX2StKhfg0ilwUi2SrejTazNZS4Zn_g_oYqENhU8c828NZakHuXaIpshLRtvNsZTM68x7NmYuSVsT0gm0rzFiDPTnb_tHLmfBNhRACnjVDVd2frB-0GXwmh8oikQO0CEeLmHxddmyNGvW5qDlKV1o5_E6R1i1bqpHCRdcO27OQyEYcGTtd4L-60FCx3Z8MkNNIzUnbGbe1lTkKlzAJI1XZ66VVSiNxdRzTaC95li0IjfhvwamydkjVOmY7lYealAZZTcuQng0LcBk9WtLEaD767Hoyk-RAwltjcY87k2hGxPzOCj0timfPdo1bYyuq5xKyM5SwEoBM5aj1hy3Ha6WWf8RsY4iEFR6vLnCUuEYPiPgr6OSK6_rW0pPqUM-5AXfdoYx8okjaCyd9S7sOAdDLfGRBjeOT74vVSUGpZD3SbXizB85kqskTm_AeIWXkjtimm2pMr5CToldxONwlnipEHRPqiqvnBaEliZOusblHvGPvMFR-mgknj5bKoP6CI-8QmfK %V 105 %X CONTEXT: C-type natriuretic peptide (CNP) is critically involved in endochondral bone growth. Variants in the genes encoding CNP or its cyclic guanosine monophosphate (cGMP)-forming receptor (natriuretic peptide receptor-B [NPR-B], gene NPR2) cause monogenic growth disorders. Here we describe a novel gain-of-function variant of NPR-B associated with tall stature and macrodactyly of the great toes (epiphyseal chondrodysplasia, Miura type). DESIGN: History and clinical characteristics of 3 family members were collected. NPR2 was selected for sequencing. Skin fibroblasts and transfected HEK-293 cells were used to compare mutant versus wild-type NPR-B activities. Homology modeling was applied to understand the molecular consequences of the variant. RESULTS: Mother's height was +2.77 standard deviation scores (SDS). The heights of her 2 daughters were +1.96 SDS at 7 years and +1.30 SDS at 4 years of age. Skeletal surveys showed macrodactyly of the great toes and pseudo-epiphyses of the mid- and proximal phalanges. Sequencing identified a novel heterozygous variant c.1444_1449delATGCTG in exon 8 of NPR2, predicted to result in deletion of 2 amino acids Met482-Leu483 within the submembrane region of NPR-B. In proband's skin fibroblasts, basal cGMP levels and CNP-stimulated cGMP production were markedly increased compared with controls. Consistently, assays with transfected HEK-293 cells showed markedly augmented baseline and ligand-dependent activity of mutant NPR-B. CONCLUSIONS: We report the second activating variant within the intracellular submembrane region of NPR-B resulting in tall stature and macrodactyly. Our functional and modeling studies suggest that this domain plays a critical role in the baseline conformation and ligand-dependent structural rearrangement of NPR-B required for cGMP production.
Alkaloid Concentrations of Lolium perenne Infected with Epichloe festucae var. lolii with Different Detection Methods-A Re-Evaluation of Intoxication Risk in Germany?. Vikuk, V.; Fuchs, B.; Krischke, M.; Mueller, M. J.; Rueb, S.; Krauss, J. In J Fungi (Basel), 6(3). 2020.
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Mycotoxins in agriculturally used plants can cause intoxication in animals and can lead to severe financial losses for farmers. The endophytic fungus Epichloe festucae var. lolii living symbiotically within the cool season grass species Lolium perenne can produce vertebrate and invertebrate toxic alkaloids. Hence, an exact quantitation of alkaloid concentrations is essential to determine intoxication risk for animals. Many studies use different methods to detect alkaloid concentrations, which complicates the comparability. In this study, we showed that alkaloid concentrations of individual plants exceeded toxicity thresholds on real world grasslands in Germany, but not on the population level. Alkaloid concentrations on five German grasslands with high alkaloid levels peaked in summer but were also below toxicity thresholds on population level. Furthermore, we showed that alkaloid concentrations follow the same seasonal trend, regardless of whether plant fresh or dry weight was used, in the field and in a common garden study. However, alkaloid concentrations were around three times higher when detected with dry weight. Finally, we showed that alkaloid concentrations can additionally be biased to different alkaloid detection methods. We highlight that toxicity risks should be analyzed using plant dry weight, but concentration trends of fresh weight are reliable.

@article{vikuk2020alkaloid, abstract = {Mycotoxins in agriculturally used plants can cause intoxication in animals and can lead to severe financial losses for farmers. The endophytic fungus Epichloe festucae var. lolii living symbiotically within the cool season grass species Lolium perenne can produce vertebrate and invertebrate toxic alkaloids. Hence, an exact quantitation of alkaloid concentrations is essential to determine intoxication risk for animals. Many studies use different methods to detect alkaloid concentrations, which complicates the comparability. In this study, we showed that alkaloid concentrations of individual plants exceeded toxicity thresholds on real world grasslands in Germany, but not on the population level. Alkaloid concentrations on five German grasslands with high alkaloid levels peaked in summer but were also below toxicity thresholds on population level. Furthermore, we showed that alkaloid concentrations follow the same seasonal trend, regardless of whether plant fresh or dry weight was used, in the field and in a common garden study. However, alkaloid concentrations were around three times higher when detected with dry weight. Finally, we showed that alkaloid concentrations can additionally be biased to different alkaloid detection methods. We highlight that toxicity risks should be analyzed using plant dry weight, but concentration trends of fresh weight are reliable.}, author = {Vikuk, V. and Fuchs, B. and Krischke, M. and Mueller, M. J. and Rueb, S. and Krauss, J.}, journal = {J Fungi (Basel)}, keywords = {uni_network}, note = {Vikuk, Veronika Fuchs, Benjamin Krischke, Markus Mueller, Martin J Rueb, Selina Krauss, Jochen eng KR 3559/3-2/Deutsche Forschungsgemeinschaft/ Switzerland 2020/09/24 J Fungi (Basel). 2020 Sep 18;6(3):177. doi: 10.3390/jof6030177.}, number = 3, title = {Alkaloid Concentrations of Lolium perenne Infected with Epichloe festucae var. lolii with Different Detection Methods-A Re-Evaluation of Intoxication Risk in Germany?}, type = {Journal Article}, volume = 6, year = 2020 }

%0 Journal Article %1 vikuk2020alkaloid %A Vikuk, V. %A Fuchs, B. %A Krischke, M. %A Mueller, M. J. %A Rueb, S. %A Krauss, J. %D 2020 %J J Fungi (Basel) %N 3 %R 10.3390/jof6030177 %T Alkaloid Concentrations of Lolium perenne Infected with Epichloe festucae var. lolii with Different Detection Methods-A Re-Evaluation of Intoxication Risk in Germany? %U https://www.ncbi.nlm.nih.gov/pubmed/32961967https://mdpi-res.com/d_attachment/jof/jof-06-00177/article_deploy/jof-06-00177-v2.pdf?version=1600695814 %V 6 %X Mycotoxins in agriculturally used plants can cause intoxication in animals and can lead to severe financial losses for farmers. The endophytic fungus Epichloe festucae var. lolii living symbiotically within the cool season grass species Lolium perenne can produce vertebrate and invertebrate toxic alkaloids. Hence, an exact quantitation of alkaloid concentrations is essential to determine intoxication risk for animals. Many studies use different methods to detect alkaloid concentrations, which complicates the comparability. In this study, we showed that alkaloid concentrations of individual plants exceeded toxicity thresholds on real world grasslands in Germany, but not on the population level. Alkaloid concentrations on five German grasslands with high alkaloid levels peaked in summer but were also below toxicity thresholds on population level. Furthermore, we showed that alkaloid concentrations follow the same seasonal trend, regardless of whether plant fresh or dry weight was used, in the field and in a common garden study. However, alkaloid concentrations were around three times higher when detected with dry weight. Finally, we showed that alkaloid concentrations can additionally be biased to different alkaloid detection methods. We highlight that toxicity risks should be analyzed using plant dry weight, but concentration trends of fresh weight are reliable.
Loss of function in the Drosophila clock gene period results in altered intermediary lipid metabolism and increased susceptibility to starvation. Schabler, S.; Amatobi, K. M.; Horn, M.; Rieger, D.; Helfrich-Forster, C.; Mueller, M. J.; Wegener, C.; Fekete, A. In Cell Mol Life Sci, 77(23), pp. 4939–4956. 2020.
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The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period(01) (per(01)) clock mutants and Canton-S wildtype (WT(CS)) flies in an isogenic and non-isogenic background using LC-MS. In the non-isogenic background, metabolites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per(01) mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WT(CS) in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per(01) mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per(01) did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per(01) mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants.

@article{schabler2020function, abstract = {The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period(01) (per(01)) clock mutants and Canton-S wildtype (WT(CS)) flies in an isogenic and non-isogenic background using LC-MS. In the non-isogenic background, metabolites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per(01) mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WT(CS) in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per(01) mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per(01) did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per(01) mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants.}, author = {Schabler, S. and Amatobi, K. M. and Horn, M. and Rieger, D. and Helfrich-Forster, C. and Mueller, M. J. and Wegener, C. and Fekete, A.}, journal = {Cell Mol Life Sci}, keywords = {uni_network}, note = {Schabler, Stefan Amatobi, Kelechi M Horn, Melanie Rieger, Dirk Helfrich-Forster, Charlotte Mueller, Martin J Wegener, Christian Fekete, Agnes eng SFB1047, Project A4/Deutsche Forschungsgemeinschaft (DFG)/ SFB1047, Project B5/Deutsche Forschungsgemeinschaft (DFG)/ SFB1047, Project B2/Deutsche Forschungsgemeinschaft (DFG)/ SFB1047, Project A1/Deutsche Forschungsgemeinschaft (DFG)/ PhD Scholarship/Graduate School of Life Sciences, University of Wuerzburg (DE)/ Switzerland 2020/01/22 Cell Mol Life Sci. 2020 Dec;77(23):4939-4956. doi: 10.1007/s00018-019-03441-6. Epub 2020 Jan 20.}, number = 23, pages = {4939-4956}, title = {Loss of function in the Drosophila clock gene period results in altered intermediary lipid metabolism and increased susceptibility to starvation}, type = {Journal Article}, volume = 77, year = 2020 }

%0 Journal Article %1 schabler2020function %A Schabler, S. %A Amatobi, K. M. %A Horn, M. %A Rieger, D. %A Helfrich-Forster, C. %A Mueller, M. J. %A Wegener, C. %A Fekete, A. %D 2020 %J Cell Mol Life Sci %N 23 %P 4939-4956 %R 10.1007/s00018-019-03441-6 %T Loss of function in the Drosophila clock gene period results in altered intermediary lipid metabolism and increased susceptibility to starvation %U https://www.ncbi.nlm.nih.gov/pubmed/31960114https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7658074/pdf/18_2019_Article_3441.pdf %V 77 %X The fruit fly Drosophila is a prime model in circadian research, but still little is known about its circadian regulation of metabolism. Daily rhythmicity in levels of several metabolites has been found, but knowledge about hydrophobic metabolites is limited. We here compared metabolite levels including lipids between period(01) (per(01)) clock mutants and Canton-S wildtype (WT(CS)) flies in an isogenic and non-isogenic background using LC-MS. In the non-isogenic background, metabolites with differing levels comprised essential amino acids, kynurenines, pterinates, glycero(phospho)lipids, and fatty acid esters. Notably, detectable diacylglycerols (DAG) and acylcarnitines (AC), involved in lipid metabolism, showed lower levels in per(01) mutants. Most of these differences disappeared in the isogenic background, yet the level differences for AC as well as DAG were consistent for fly bodies. AC levels were dependent on the time of day in WT(CS) in phase with food consumption under LD conditions, while DAGs showed weak daily oscillations. Two short-chain ACs continued to cycle even in constant darkness. per(01) mutants in LD showed no or very weak diel AC oscillations out of phase with feeding activity. The low levels of DAGs and ACs in per(01) did not correlate with lower total food consumption, body mass or weight. Clock mutant flies showed higher sensitivity to starvation independent of their background-dependent activity level. Our results suggest that neither feeding, energy storage nor mobilisation is significantly affected in per(01) mutants, but point towards impaired mitochondrial activity, supported by upregulation of the mitochondrial stress marker 4EBP in the clock mutants.
Chemical Priming by Isothiocyanates Protects Against Intoxication by Products of the Mustard Oil Bomb. Ferber, E.; Gerhards, J.; Sauer, M.; Krischke, M.; Dittrich, M. T.; Muller, T.; Berger, S.; Fekete, A.; Mueller, M. J. In Front Plant Sci, 11, p. 887. 2020.
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In Brassicaceae, tissue damage triggers the mustard oil bomb i.e., activates the degradation of glucosinolates by myrosinases leading to a rapid accumulation of isothiocyanates at the site of damage. Isothiocyanates are reactive electrophilic species (RES) known to covalently bind to thiols in proteins and glutathione, a process that is not only toxic to herbivores and microbes but can also cause cell death of healthy plant tissues. Previously, it has been shown that subtoxic isothiocyanate concentrations can induce transcriptional reprogramming in intact plant cells. Glutathione depletion by RES leading to breakdown of the redox potential has been proposed as a central and common RES signal transduction mechanism. Using transcriptome analyses, we show that after exposure of Arabidopsis seedlings (grown in liquid culture) to subtoxic concentrations of sulforaphane hundreds of genes were regulated without depletion of the cellular glutathione pool. Heat shock genes were among the most highly up-regulated genes and this response was found to be dependent on the canonical heat shock factors A1 (HSFA1). HSFA1-deficient plants were more sensitive to isothiocyanates than wild type plants. Moreover, pretreatment of Arabidopsis seedlings with subtoxic concentrations of isothiocyanates increased resistance against exposure to toxic levels of isothiocyanates and, hence, may reduce the autotoxicity of the mustard oil bomb by inducing cell protection mechanisms.

@article{ferber2020chemical, abstract = {In Brassicaceae, tissue damage triggers the mustard oil bomb i.e., activates the degradation of glucosinolates by myrosinases leading to a rapid accumulation of isothiocyanates at the site of damage. Isothiocyanates are reactive electrophilic species (RES) known to covalently bind to thiols in proteins and glutathione, a process that is not only toxic to herbivores and microbes but can also cause cell death of healthy plant tissues. Previously, it has been shown that subtoxic isothiocyanate concentrations can induce transcriptional reprogramming in intact plant cells. Glutathione depletion by RES leading to breakdown of the redox potential has been proposed as a central and common RES signal transduction mechanism. Using transcriptome analyses, we show that after exposure of Arabidopsis seedlings (grown in liquid culture) to subtoxic concentrations of sulforaphane hundreds of genes were regulated without depletion of the cellular glutathione pool. Heat shock genes were among the most highly up-regulated genes and this response was found to be dependent on the canonical heat shock factors A1 (HSFA1). HSFA1-deficient plants were more sensitive to isothiocyanates than wild type plants. Moreover, pretreatment of Arabidopsis seedlings with subtoxic concentrations of isothiocyanates increased resistance against exposure to toxic levels of isothiocyanates and, hence, may reduce the autotoxicity of the mustard oil bomb by inducing cell protection mechanisms.}, author = {Ferber, E. and Gerhards, J. and Sauer, M. and Krischke, M. and Dittrich, M. T. and Muller, T. and Berger, S. and Fekete, A. and Mueller, M. J.}, journal = {Front Plant Sci}, keywords = {uni_network}, note = {Ferber, Elena Gerhards, Julian Sauer, Miriam Krischke, Markus Dittrich, Marcus T Muller, Tobias Berger, Susanne Fekete, Agnes Mueller, Martin J eng Switzerland 2020/07/18 Front Plant Sci. 2020 Jun 26;11:887. doi: 10.3389/fpls.2020.00887. eCollection 2020.}, pages = 887, title = {Chemical Priming by Isothiocyanates Protects Against Intoxication by Products of the Mustard Oil Bomb}, type = {Journal Article}, volume = 11, year = 2020 }

%0 Journal Article %1 ferber2020chemical %A Ferber, E. %A Gerhards, J. %A Sauer, M. %A Krischke, M. %A Dittrich, M. T. %A Muller, T. %A Berger, S. %A Fekete, A. %A Mueller, M. J. %D 2020 %J Front Plant Sci %P 887 %R 10.3389/fpls.2020.00887 %T Chemical Priming by Isothiocyanates Protects Against Intoxication by Products of the Mustard Oil Bomb %U https://www.ncbi.nlm.nih.gov/pubmed/32676087https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7333730/pdf/fpls-11-00887.pdf %V 11 %X In Brassicaceae, tissue damage triggers the mustard oil bomb i.e., activates the degradation of glucosinolates by myrosinases leading to a rapid accumulation of isothiocyanates at the site of damage. Isothiocyanates are reactive electrophilic species (RES) known to covalently bind to thiols in proteins and glutathione, a process that is not only toxic to herbivores and microbes but can also cause cell death of healthy plant tissues. Previously, it has been shown that subtoxic isothiocyanate concentrations can induce transcriptional reprogramming in intact plant cells. Glutathione depletion by RES leading to breakdown of the redox potential has been proposed as a central and common RES signal transduction mechanism. Using transcriptome analyses, we show that after exposure of Arabidopsis seedlings (grown in liquid culture) to subtoxic concentrations of sulforaphane hundreds of genes were regulated without depletion of the cellular glutathione pool. Heat shock genes were among the most highly up-regulated genes and this response was found to be dependent on the canonical heat shock factors A1 (HSFA1). HSFA1-deficient plants were more sensitive to isothiocyanates than wild type plants. Moreover, pretreatment of Arabidopsis seedlings with subtoxic concentrations of isothiocyanates increased resistance against exposure to toxic levels of isothiocyanates and, hence, may reduce the autotoxicity of the mustard oil bomb by inducing cell protection mechanisms.
The Venus flytrap trigger hair-specific potassium channel KDM1 can reestablish the K+ gradient required for hapto-electric signaling. Iosip, A. L.; Bohm, J.; Scherzer, S.; Al-Rasheid, K. A. S.; Dreyer, I.; Schultz, J.; Becker, D.; Kreuzer, I.; Hedrich, R. In PLoS Biol, 18(12), p. e3000964. 2020.
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The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula's trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair's sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula's hapto-electric signaling.

@article{iosip2020venus, abstract = {The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula's trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair's sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula's hapto-electric signaling.}, author = {Iosip, A. L. and Bohm, J. and Scherzer, S. and Al-Rasheid, K. A. S. and Dreyer, I. and Schultz, J. and Becker, D. and Kreuzer, I. and Hedrich, R.}, journal = {PLoS Biol}, keywords = {Potentials/physiology}, note = {Iosip, Anda L Bohm, Jennifer Scherzer, Sonke Al-Rasheid, Khaled A S Dreyer, Ingo Schultz, Jorg Becker, Dirk Kreuzer, Ines Hedrich, Rainer eng Research Support, Non-U.S. Gov't 2020/12/10 PLoS Biol. 2020 Dec 9;18(12):e3000964. doi: 10.1371/journal.pbio.3000964. eCollection 2020 Dec.}, number = 12, pages = {e3000964}, title = {The Venus flytrap trigger hair-specific potassium channel KDM1 can reestablish the K+ gradient required for hapto-electric signaling}, type = {Journal Article}, volume = 18, year = 2020 }

%0 Journal Article %1 iosip2020venus %A Iosip, A. L. %A Bohm, J. %A Scherzer, S. %A Al-Rasheid, K. A. S. %A Dreyer, I. %A Schultz, J. %A Becker, D. %A Kreuzer, I. %A Hedrich, R. %D 2020 %J PLoS Biol %N 12 %P e3000964 %R 10.1371/journal.pbio.3000964 %T The Venus flytrap trigger hair-specific potassium channel KDM1 can reestablish the K+ gradient required for hapto-electric signaling %U https://www.ncbi.nlm.nih.gov/pubmed/33296375https://journals.plos.org/plosbiology/article/file?id=10.1371/journal.pbio.3000964&type=printable %V 18 %X The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula's trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair's sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula's hapto-electric signaling.
Comparison of extraction efficiency and selectivity between low-temperature pressurized microwave-assisted extraction and prolonged maceration. Masota, N. E.; Vogg, G.; Heller, E.; Holzgrabe, U. In Arch Pharm (Weinheim), 353(10), p. e2000147. 2020.
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Extraction is a key step in studying compounds from plants and other natural sources. The common use of high temperatures in pressurized microwave-assisted extraction (PMAE) makes it unsuitable for the extraction of compounds with low or unknown thermal stability. This study aimed at determining the suitability of low-temperature, short-time PMAE in attaining yields comparable to those of prolonged maceration at room temperature. Additionally, we explored the phytochemical differences of the extracts from both techniques. Maceration at room temperature for 24 hr and PMAE at 40-45 degrees C and 10 bar for 30 min were carried out on 18 samples from 14 plant species at a solvent-to-feeds ratio of 10. The PMAE yields of 16 out of 18 samples were within the proportions of 91-139.2% as compared with the respective extracts from maceration. Varying numbers of nonmatching peaks were noted in MS chromatograms of five extract pairs, indicating selective extraction of some compounds. Low-temperature PMAE can attain reasonable extraction efficiency with the added value of sparing compounds of low thermal stability. The method can also enable the recovery of compounds distinct from those obtained by maceration.

@article{masota2020comparison, abstract = {Extraction is a key step in studying compounds from plants and other natural sources. The common use of high temperatures in pressurized microwave-assisted extraction (PMAE) makes it unsuitable for the extraction of compounds with low or unknown thermal stability. This study aimed at determining the suitability of low-temperature, short-time PMAE in attaining yields comparable to those of prolonged maceration at room temperature. Additionally, we explored the phytochemical differences of the extracts from both techniques. Maceration at room temperature for 24 hr and PMAE at 40-45 degrees C and 10 bar for 30 min were carried out on 18 samples from 14 plant species at a solvent-to-feeds ratio of 10. The PMAE yields of 16 out of 18 samples were within the proportions of 91-139.2% as compared with the respective extracts from maceration. Varying numbers of nonmatching peaks were noted in MS chromatograms of five extract pairs, indicating selective extraction of some compounds. Low-temperature PMAE can attain reasonable extraction efficiency with the added value of sparing compounds of low thermal stability. The method can also enable the recovery of compounds distinct from those obtained by maceration.}, author = {Masota, N. E. and Vogg, G. and Heller, E. and Holzgrabe, U.}, journal = {Arch Pharm (Weinheim)}, keywords = {Chromatography}, note = {Masota, Nelson E Vogg, Gerd Heller, Eberhard Holzgrabe, Ulrike eng 2018/19 (57381412)/Deutscher Akademischer Austauschdienst/ Comparative Study Germany 2020/09/01 Arch Pharm (Weinheim). 2020 Oct;353(10):e2000147. doi: 10.1002/ardp.202000147. Epub 2020 Aug 31.}, number = 10, pages = {e2000147}, title = {Comparison of extraction efficiency and selectivity between low-temperature pressurized microwave-assisted extraction and prolonged maceration}, type = {Journal Article}, volume = 353, year = 2020 }

%0 Journal Article %1 masota2020comparison %A Masota, N. E. %A Vogg, G. %A Heller, E. %A Holzgrabe, U. %D 2020 %J Arch Pharm (Weinheim) %N 10 %P e2000147 %R 10.1002/ardp.202000147 %T Comparison of extraction efficiency and selectivity between low-temperature pressurized microwave-assisted extraction and prolonged maceration %U https://www.ncbi.nlm.nih.gov/pubmed/32865816 %V 353 %X Extraction is a key step in studying compounds from plants and other natural sources. The common use of high temperatures in pressurized microwave-assisted extraction (PMAE) makes it unsuitable for the extraction of compounds with low or unknown thermal stability. This study aimed at determining the suitability of low-temperature, short-time PMAE in attaining yields comparable to those of prolonged maceration at room temperature. Additionally, we explored the phytochemical differences of the extracts from both techniques. Maceration at room temperature for 24 hr and PMAE at 40-45 degrees C and 10 bar for 30 min were carried out on 18 samples from 14 plant species at a solvent-to-feeds ratio of 10. The PMAE yields of 16 out of 18 samples were within the proportions of 91-139.2% as compared with the respective extracts from maceration. Varying numbers of nonmatching peaks were noted in MS chromatograms of five extract pairs, indicating selective extraction of some compounds. Low-temperature PMAE can attain reasonable extraction efficiency with the added value of sparing compounds of low thermal stability. The method can also enable the recovery of compounds distinct from those obtained by maceration.
CRISPR/Cas 9-Mediated Mutations as a New Tool for Studying Taste in Honeybees. Degirmenci, L.; Geiger, D.; Roge Ferreira, F. L.; Keller, A.; Krischke, B.; Beye, M.; Steffan-Dewenter, I.; Scheiner, R. In Chem Senses, 45(8), pp. 655–666. 2020.
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Honeybees rely on nectar as their main source of carbohydrates. Sucrose, glucose, and fructose are the main components of plant nectars. Intriguingly, honeybees express only 3 putative sugar receptors (AmGr1, AmGr2, and AmGr3), which is in stark contrast to many other insects and vertebrates. The sugar receptors are only partially characterized. AmGr1 detects different sugars including sucrose and glucose. AmGr2 is assumed to act as a co-receptor only, while AmGr3 is assumedly a fructose receptor. We show that honeybee gustatory receptor AmGr3 is highly specialized for fructose perception when expressed in Xenopus oocytes. When we introduced nonsense mutations to the respective AmGr3 gene using CRISPR/Cas9 in eggs of female workers, the resulting mutants displayed almost a complete loss of responsiveness to fructose. In contrast, responses to sucrose were normal. Nonsense mutations introduced by CRISPR/Cas9 in honeybees can thus induce a measurable behavioral change and serve to characterize the function of taste receptors in vivo. CRISPR/Cas9 is an excellent novel tool for characterizing honeybee taste receptors in vivo. Biophysical receptor characterization in Xenopus oocytes and nonsense mutation of AmGr3 in honeybees unequivocally demonstrate that this receptor is highly specific for fructose.

@article{degirmenci2020crisprcas, abstract = {Honeybees rely on nectar as their main source of carbohydrates. Sucrose, glucose, and fructose are the main components of plant nectars. Intriguingly, honeybees express only 3 putative sugar receptors (AmGr1, AmGr2, and AmGr3), which is in stark contrast to many other insects and vertebrates. The sugar receptors are only partially characterized. AmGr1 detects different sugars including sucrose and glucose. AmGr2 is assumed to act as a co-receptor only, while AmGr3 is assumedly a fructose receptor. We show that honeybee gustatory receptor AmGr3 is highly specialized for fructose perception when expressed in Xenopus oocytes. When we introduced nonsense mutations to the respective AmGr3 gene using CRISPR/Cas9 in eggs of female workers, the resulting mutants displayed almost a complete loss of responsiveness to fructose. In contrast, responses to sucrose were normal. Nonsense mutations introduced by CRISPR/Cas9 in honeybees can thus induce a measurable behavioral change and serve to characterize the function of taste receptors in vivo. CRISPR/Cas9 is an excellent novel tool for characterizing honeybee taste receptors in vivo. Biophysical receptor characterization in Xenopus oocytes and nonsense mutation of AmGr3 in honeybees unequivocally demonstrate that this receptor is highly specific for fructose.}, author = {Degirmenci, L. and Geiger, D. and Roge Ferreira, F. L. and Keller, A. and Krischke, B. and Beye, M. and Steffan-Dewenter, I. and Scheiner, R.}, journal = {Chem Senses}, keywords = {uni_network}, note = {Degirmenci, Laura Geiger, Dietmar Roge Ferreira, Fabio Luiz Keller, Alexander Krischke, Beate Beye, Martin Steffan-Dewenter, Ingolf Scheiner, Ricarda eng Research Support, Non-U.S. Gov't England 2020/09/25 Chem Senses. 2020 Nov 7;45(8):655-666. doi: 10.1093/chemse/bjaa063.}, number = 8, pages = {655-666}, title = {CRISPR/Cas 9-Mediated Mutations as a New Tool for Studying Taste in Honeybees}, type = {Journal Article}, volume = 45, year = 2020 }

%0 Journal Article %1 degirmenci2020crisprcas %A Degirmenci, L. %A Geiger, D. %A Roge Ferreira, F. L. %A Keller, A. %A Krischke, B. %A Beye, M. %A Steffan-Dewenter, I. %A Scheiner, R. %D 2020 %J Chem Senses %N 8 %P 655-666 %R 10.1093/chemse/bjaa063 %T CRISPR/Cas 9-Mediated Mutations as a New Tool for Studying Taste in Honeybees %U https://www.ncbi.nlm.nih.gov/pubmed/32968780https://watermark.silverchair.com/bjaa063.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAA1YwggNSBgkqhkiG9w0BBwagggNDMIIDPwIBADCCAzgGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMYMUrAcQMAfk-q7Z7AgEQgIIDCSOX1Oggh-RJhEw1awG9K2lgW8gb7z__ZPVyU56PT8fit3EwMN2kKwtPlZG2l0HV9zrx6T7Clat0p1hne5HHgLrZ72y-i9-0eGK73UU2kNgo6lxvuARctRvT3j-glKgmMYI-RKE_f-vr6VabOWlI10UcjX1OKKLv_xwBLbxMp8j-uHOOS4K5vFx6Q91TR8KNT-Kxsdt75EP3aywxUSMSL0Q24cwMQ3SzSQeGYXm2ci6yaEMnHGpL_0edMv8T1LVCKf7Ba-1vbOxsdXP_ZEPiLd-u36cXoGUzXlFg9h6dy_Yp4zEvdb5ureJvCT39g_Zes5BnhzDiskjKDMdru01Ebv-IdjrnWkWhKUhol1oBuq5pJX2FnUu8bkWjHaysN8uAfBpN_e-ZHcpPfbhE56GVJrRLFXTAHiQ-TZWmTfwoGH_9RcMawqXtEPYTl0f6cj2nJjye_BGrEJZcKqXrBA7fJvbkqdO9rcMUZEv8wmXT6-0dQIsIJivRJP6SDcr0Lgz5Xt5LxqiYcGooHAaj2F-Fm5xcOnXFy2WbzbYCUou5taNErH9anqxE6knvPHZbiBhzUYr8z9lDZQB0pAx0gp42SsHlvOVHTnzAGbKWZErZmx2Elq_88aN6c8RNh1bcQJFPBIrEoRemdAq3Mt7PyQa8BuQNrDkB1ia8u4HUTabkMc8Ff78Fv1jBOiDwhnVXOBGkSa6MqNRYsrkLxot-QhixM271e7qmskBDpbyyxlZ8RWr8nFhmzR9P-L2hP5S-8zI7hw983CmtTEFTvYRvs0h94IZy227e93_6uX6IhURbjLvyerBrJH8EVpw-qUXV6ive7iM6PI7r1h9vOMeXgHNR_ArQCj4qkabxqFxKUTA-pIXGOfmHq5YZ0MSdn113yt4i6LdaTmcVqY6kxkTEw7foeHOojGEeZo6Dgzoh-ViO2srEfFrBy1K6mdvKxyvceTIs--V-ti7nlsoCwFOXyyawA2cB6QV0eO1m8ya8y0QtgJZkwKRf49Tm_VifXs_KSGyOn7AJbyhhnccFFA %V 45 %X Honeybees rely on nectar as their main source of carbohydrates. Sucrose, glucose, and fructose are the main components of plant nectars. Intriguingly, honeybees express only 3 putative sugar receptors (AmGr1, AmGr2, and AmGr3), which is in stark contrast to many other insects and vertebrates. The sugar receptors are only partially characterized. AmGr1 detects different sugars including sucrose and glucose. AmGr2 is assumed to act as a co-receptor only, while AmGr3 is assumedly a fructose receptor. We show that honeybee gustatory receptor AmGr3 is highly specialized for fructose perception when expressed in Xenopus oocytes. When we introduced nonsense mutations to the respective AmGr3 gene using CRISPR/Cas9 in eggs of female workers, the resulting mutants displayed almost a complete loss of responsiveness to fructose. In contrast, responses to sucrose were normal. Nonsense mutations introduced by CRISPR/Cas9 in honeybees can thus induce a measurable behavioral change and serve to characterize the function of taste receptors in vivo. CRISPR/Cas9 is an excellent novel tool for characterizing honeybee taste receptors in vivo. Biophysical receptor characterization in Xenopus oocytes and nonsense mutation of AmGr3 in honeybees unequivocally demonstrate that this receptor is highly specific for fructose.

2019[ to top ]

Infection Rates and Alkaloid Patterns of Different Grass Species with Systemic Epichloe Endophytes. Vikuk, V.; Young, C. A.; Lee, S. T.; Nagabhyru, P.; Krischke, M.; Mueller, M. J.; Krauss, J. In Appl Environ Microbiol, 85(17). 2019.
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Symbiotic Epichloe species are fungal endophytes of cool-season grasses that can produce alkaloids with toxicity to vertebrates and/or invertebrates. Monitoring infections and presence of alkaloids in grasses infected with Epichloe species can provide an estimate of possible intoxication risks for livestock. We sampled 3,046 individuals of 13 different grass species in three regions on 150 study sites in Germany. We determined infection rates and used PCR to identify Epichloe species diversity based on the presence of different alkaloid biosynthesis genes, then confirmed the possible chemotypes with high-performance liquid chromatography (HPLC)/ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) measurements. Infections of Epichloe spp. were found in Festuca pratensis Huds. (81%), Festuca ovina L. aggregate (agg.) (73%), Lolium perenne L. (15%), Festuca rubra L. (15%) and Dactylis glomerata L. (8%). The other eight grass species did not appear to be infected. For the majority of Epichloe-infected L. perenne samples (98%), the alkaloids lolitrem B and peramine were present, but ergovaline was not detected, which was consistent with the genetic evaluation, as dmaW, the gene encoding the first step of the ergot alkaloid biosynthesis pathway, was absent. Epichloe uncinata in F. pratensis produced anti-insect loline compounds. The Epichloe spp. observed in the F. ovina agg. samples showed the greatest level of diversity, and different intermediates of the indole-diterpene pathway could be detected. Epichloe infection rates alone are insufficient to estimate intoxication risks for livestock, as other factors, like the ability of the endophyte to produce the alkaloids, also need to be assessed.IMPORTANCE Severe problems of livestock intoxication from Epichloe-infected forage grasses have been reported from New Zealand, Australia, and the United States, but much less frequently from Europe, and particularly not from Germany. Nevertheless, it is important to monitor infection rates and alkaloids of grasses with Epichloe fungi to estimate possible intoxication risks. Most studies focus on agricultural grass species like Lolium perenne and Festuca arundinacea, but other cool-season grass species can also be infected. We show that in Germany, infection rates and alkaloids differ between grass species and that some of the alkaloids can be toxic to livestock. Changes in grassland management due to changing climate, especially with a shift toward grasslands dominated with Epichloe-infected species such as Lolium perenne, may result in greater numbers of intoxicated livestock in the near future. We therefore suggest regular monitoring of grass species for infections and alkaloids and call for maintaining heterogenous grasslands for livestock.

@article{vikuk2019infection, abstract = {Symbiotic Epichloe species are fungal endophytes of cool-season grasses that can produce alkaloids with toxicity to vertebrates and/or invertebrates. Monitoring infections and presence of alkaloids in grasses infected with Epichloe species can provide an estimate of possible intoxication risks for livestock. We sampled 3,046 individuals of 13 different grass species in three regions on 150 study sites in Germany. We determined infection rates and used PCR to identify Epichloe species diversity based on the presence of different alkaloid biosynthesis genes, then confirmed the possible chemotypes with high-performance liquid chromatography (HPLC)/ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) measurements. Infections of Epichloe spp. were found in Festuca pratensis Huds. (81%), Festuca ovina L. aggregate (agg.) (73%), Lolium perenne L. (15%), Festuca rubra L. (15%) and Dactylis glomerata L. (8%). The other eight grass species did not appear to be infected. For the majority of Epichloe-infected L. perenne samples (98%), the alkaloids lolitrem B and peramine were present, but ergovaline was not detected, which was consistent with the genetic evaluation, as dmaW, the gene encoding the first step of the ergot alkaloid biosynthesis pathway, was absent. Epichloe uncinata in F. pratensis produced anti-insect loline compounds. The Epichloe spp. observed in the F. ovina agg. samples showed the greatest level of diversity, and different intermediates of the indole-diterpene pathway could be detected. Epichloe infection rates alone are insufficient to estimate intoxication risks for livestock, as other factors, like the ability of the endophyte to produce the alkaloids, also need to be assessed.IMPORTANCE Severe problems of livestock intoxication from Epichloe-infected forage grasses have been reported from New Zealand, Australia, and the United States, but much less frequently from Europe, and particularly not from Germany. Nevertheless, it is important to monitor infection rates and alkaloids of grasses with Epichloe fungi to estimate possible intoxication risks. Most studies focus on agricultural grass species like Lolium perenne and Festuca arundinacea, but other cool-season grass species can also be infected. We show that in Germany, infection rates and alkaloids differ between grass species and that some of the alkaloids can be toxic to livestock. Changes in grassland management due to changing climate, especially with a shift toward grasslands dominated with Epichloe-infected species such as Lolium perenne, may result in greater numbers of intoxicated livestock in the near future. We therefore suggest regular monitoring of grass species for infections and alkaloids and call for maintaining heterogenous grasslands for livestock.}, author = {Vikuk, V. and Young, C. A. and Lee, S. T. and Nagabhyru, P. and Krischke, M. and Mueller, M. J. and Krauss, J.}, journal = {Appl Environ Microbiol}, keywords = {Alkaloids/*analysis}, note = {Vikuk, Veronika Young, Carolyn A Lee, Stephen T Nagabhyru, Padmaja Krischke, Markus Mueller, Martin J Krauss, Jochen eng Research Support, Non-U.S. Gov't 2019/06/23 Appl Environ Microbiol. 2019 Aug 14;85(17):e00465-19. doi: 10.1128/AEM.00465-19. Print 2019 Sep 1.}, number = 17, title = {Infection Rates and Alkaloid Patterns of Different Grass Species with Systemic Epichloe Endophytes}, type = {Journal Article}, volume = 85, year = 2019 }

%0 Journal Article %1 vikuk2019infection %A Vikuk, V. %A Young, C. A. %A Lee, S. T. %A Nagabhyru, P. %A Krischke, M. %A Mueller, M. J. %A Krauss, J. %D 2019 %J Appl Environ Microbiol %N 17 %R 10.1128/AEM.00465-19 %T Infection Rates and Alkaloid Patterns of Different Grass Species with Systemic Epichloe Endophytes %U https://www.ncbi.nlm.nih.gov/pubmed/31227553https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6696963/pdf/AEM.00465-19.pdf %V 85 %X Symbiotic Epichloe species are fungal endophytes of cool-season grasses that can produce alkaloids with toxicity to vertebrates and/or invertebrates. Monitoring infections and presence of alkaloids in grasses infected with Epichloe species can provide an estimate of possible intoxication risks for livestock. We sampled 3,046 individuals of 13 different grass species in three regions on 150 study sites in Germany. We determined infection rates and used PCR to identify Epichloe species diversity based on the presence of different alkaloid biosynthesis genes, then confirmed the possible chemotypes with high-performance liquid chromatography (HPLC)/ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) measurements. Infections of Epichloe spp. were found in Festuca pratensis Huds. (81%), Festuca ovina L. aggregate (agg.) (73%), Lolium perenne L. (15%), Festuca rubra L. (15%) and Dactylis glomerata L. (8%). The other eight grass species did not appear to be infected. For the majority of Epichloe-infected L. perenne samples (98%), the alkaloids lolitrem B and peramine were present, but ergovaline was not detected, which was consistent with the genetic evaluation, as dmaW, the gene encoding the first step of the ergot alkaloid biosynthesis pathway, was absent. Epichloe uncinata in F. pratensis produced anti-insect loline compounds. The Epichloe spp. observed in the F. ovina agg. samples showed the greatest level of diversity, and different intermediates of the indole-diterpene pathway could be detected. Epichloe infection rates alone are insufficient to estimate intoxication risks for livestock, as other factors, like the ability of the endophyte to produce the alkaloids, also need to be assessed.IMPORTANCE Severe problems of livestock intoxication from Epichloe-infected forage grasses have been reported from New Zealand, Australia, and the United States, but much less frequently from Europe, and particularly not from Germany. Nevertheless, it is important to monitor infection rates and alkaloids of grasses with Epichloe fungi to estimate possible intoxication risks. Most studies focus on agricultural grass species like Lolium perenne and Festuca arundinacea, but other cool-season grass species can also be infected. We show that in Germany, infection rates and alkaloids differ between grass species and that some of the alkaloids can be toxic to livestock. Changes in grassland management due to changing climate, especially with a shift toward grasslands dominated with Epichloe-infected species such as Lolium perenne, may result in greater numbers of intoxicated livestock in the near future. We therefore suggest regular monitoring of grass species for infections and alkaloids and call for maintaining heterogenous grasslands for livestock.
Specification of BMP Signaling. Nickel, J.; Mueller, T. D. In Cells, 8(12). 2019.
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Bone Morphogenetic Proteins (BMPs) together with the Growth and Differentiation Factors (GDFs) form the largest subgroup of the Transforming Growth Factor (TGF)beta family and represent secreted growth factors, which play an essential role in many aspects of cell communication in higher organisms. As morphogens they exert crucial functions during embryonal development, but are also involved in tissue homeostasis and regeneration in the adult organism. Their involvement in maintenance and repair processes of various tissues and organs made these growth factors highly interesting targets for novel pharmaceutical applications in regenerative medicine. A hallmark of the TGFbeta protein family is that all of the more than 30 growth factors identified to date signal by binding and hetero-oligomerization of a very limited set of transmembrane serine-threonine kinase receptors, which can be classified into two subgroups termed type I and type II. Only seven type I and five type II receptors exist for all 30plus TGFbeta members suggesting a pronounced ligand-receptor promiscuity. Indeed, many TGFbeta ligands can bind the same type I or type II receptor and a particular receptor of either subtype can usually interact with and bind various TGFbeta ligands. The possible consequence of this ligand-receptor promiscuity is further aggravated by the finding that canonical TGFbeta signaling of all family members seemingly results in the activation of just two distinct signaling pathways, that is either SMAD2/3 or SMAD1/5/8 activation. While this would implicate that different ligands can assemble seemingly identical receptor complexes that activate just either one of two distinct pathways, in vitro and in vivo analyses show that the different TGFbeta members exert quite distinct biological functions with high specificity. This discrepancy indicates that our current view of TGFbeta signaling initiation just by hetero-oligomerization of two receptor subtypes and transduction via two main pathways in an on-off switch manner is too simplified. Hence, the signals generated by the various TGFbeta members are either quantitatively interpreted using the subtle differences in their receptor-binding properties leading to ligand-specific modulation of the downstream signaling cascade or additional components participating in the signaling activation complex allow diversification of the encoded signal in a ligand-dependent manner at all cellular levels. In this review we focus on signal specification of TGFbeta members, particularly of BMPs and GDFs addressing the role of binding affinities, specificities, and kinetics of individual ligand-receptor interactions for the assembly of specific receptor complexes with potentially distinct signaling properties.

@article{nickel2019specification, abstract = {Bone Morphogenetic Proteins (BMPs) together with the Growth and Differentiation Factors (GDFs) form the largest subgroup of the Transforming Growth Factor (TGF)beta family and represent secreted growth factors, which play an essential role in many aspects of cell communication in higher organisms. As morphogens they exert crucial functions during embryonal development, but are also involved in tissue homeostasis and regeneration in the adult organism. Their involvement in maintenance and repair processes of various tissues and organs made these growth factors highly interesting targets for novel pharmaceutical applications in regenerative medicine. A hallmark of the TGFbeta protein family is that all of the more than 30 growth factors identified to date signal by binding and hetero-oligomerization of a very limited set of transmembrane serine-threonine kinase receptors, which can be classified into two subgroups termed type I and type II. Only seven type I and five type II receptors exist for all 30plus TGFbeta members suggesting a pronounced ligand-receptor promiscuity. Indeed, many TGFbeta ligands can bind the same type I or type II receptor and a particular receptor of either subtype can usually interact with and bind various TGFbeta ligands. The possible consequence of this ligand-receptor promiscuity is further aggravated by the finding that canonical TGFbeta signaling of all family members seemingly results in the activation of just two distinct signaling pathways, that is either SMAD2/3 or SMAD1/5/8 activation. While this would implicate that different ligands can assemble seemingly identical receptor complexes that activate just either one of two distinct pathways, in vitro and in vivo analyses show that the different TGFbeta members exert quite distinct biological functions with high specificity. This discrepancy indicates that our current view of TGFbeta signaling initiation just by hetero-oligomerization of two receptor subtypes and transduction via two main pathways in an on-off switch manner is too simplified. Hence, the signals generated by the various TGFbeta members are either quantitatively interpreted using the subtle differences in their receptor-binding properties leading to ligand-specific modulation of the downstream signaling cascade or additional components participating in the signaling activation complex allow diversification of the encoded signal in a ligand-dependent manner at all cellular levels. In this review we focus on signal specification of TGFbeta members, particularly of BMPs and GDFs addressing the role of binding affinities, specificities, and kinetics of individual ligand-receptor interactions for the assembly of specific receptor complexes with potentially distinct signaling properties.}, author = {Nickel, J. and Mueller, T. D.}, journal = {Cells}, keywords = {uni_network}, note = {Nickel, Joachim Mueller, Thomas D eng Research Support, Non-U.S. Gov't Review Switzerland 2019/12/11 Cells. 2019 Dec 5;8(12):1579. doi: 10.3390/cells8121579.}, number = 12, title = {Specification of BMP Signaling}, type = {Journal Article}, volume = 8, year = 2019 }

%0 Journal Article %1 nickel2019specification %A Nickel, J. %A Mueller, T. D. %D 2019 %J Cells %N 12 %R 10.3390/cells8121579 %T Specification of BMP Signaling %U https://www.ncbi.nlm.nih.gov/pubmed/31817503https://mdpi-res.com/d_attachment/cells/cells-08-01579/article_deploy/cells-08-01579-v2.pdf?version=1576664953 %V 8 %X Bone Morphogenetic Proteins (BMPs) together with the Growth and Differentiation Factors (GDFs) form the largest subgroup of the Transforming Growth Factor (TGF)beta family and represent secreted growth factors, which play an essential role in many aspects of cell communication in higher organisms. As morphogens they exert crucial functions during embryonal development, but are also involved in tissue homeostasis and regeneration in the adult organism. Their involvement in maintenance and repair processes of various tissues and organs made these growth factors highly interesting targets for novel pharmaceutical applications in regenerative medicine. A hallmark of the TGFbeta protein family is that all of the more than 30 growth factors identified to date signal by binding and hetero-oligomerization of a very limited set of transmembrane serine-threonine kinase receptors, which can be classified into two subgroups termed type I and type II. Only seven type I and five type II receptors exist for all 30plus TGFbeta members suggesting a pronounced ligand-receptor promiscuity. Indeed, many TGFbeta ligands can bind the same type I or type II receptor and a particular receptor of either subtype can usually interact with and bind various TGFbeta ligands. The possible consequence of this ligand-receptor promiscuity is further aggravated by the finding that canonical TGFbeta signaling of all family members seemingly results in the activation of just two distinct signaling pathways, that is either SMAD2/3 or SMAD1/5/8 activation. While this would implicate that different ligands can assemble seemingly identical receptor complexes that activate just either one of two distinct pathways, in vitro and in vivo analyses show that the different TGFbeta members exert quite distinct biological functions with high specificity. This discrepancy indicates that our current view of TGFbeta signaling initiation just by hetero-oligomerization of two receptor subtypes and transduction via two main pathways in an on-off switch manner is too simplified. Hence, the signals generated by the various TGFbeta members are either quantitatively interpreted using the subtle differences in their receptor-binding properties leading to ligand-specific modulation of the downstream signaling cascade or additional components participating in the signaling activation complex allow diversification of the encoded signal in a ligand-dependent manner at all cellular levels. In this review we focus on signal specification of TGFbeta members, particularly of BMPs and GDFs addressing the role of binding affinities, specificities, and kinetics of individual ligand-receptor interactions for the assembly of specific receptor complexes with potentially distinct signaling properties.
Rat Organic Cation Transporter 1 Contains Three Binding Sites for Substrate 1-Methyl-4-phenylpyridinium per Monomer. Keller, T.; Gorboulev, V.; Mueller, T. D.; Dotsch, V.; Bernhard, F.; Koepsell, H. In Mol Pharmacol, 95(2), pp. 169–182. 2019.
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Organic cation transporters OCT1 (SLC22A1) and OCT2 (SLC22A2) are critically involved in absorption and excretion of diverse cationic drugs. Because drug-drug interactions at these transporters may induce adverse drug effects in patients, in vitro testing during drug development for interaction with the human transporters is mandatory. Recent data performed with rat OCT1 (rOCT1) suggest that currently performed in vitro tests assuming one polyspecific binding site are insufficient. Here we measured the binding and transport of model substrate 1-methyl-4-phenylpyridinium(+) (MPP(+)) by cell-free-expressed fusion proteins of rOCT1 and rOCT1 mutants with green fluorescent protein that had been reconstituted into nanodiscs or proteoliposomes. The nanodiscs were formed with major scaffold protein (MSP) and different phospholipids, whereas the proteoliposomes were formed with a mixture of cholesterol, phosphatidylserine, and phosphatidylcholine. In nanodiscs formed with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine or cholesterol, phosphatidylserine, and phosphatidylcholine, two low-affinity MPP(+) binding sites and one high-affinity MPP(+) binding site per transporter monomer were determined. Mutagenesis revealed that tryptophan 218 and aspartate 475 in neighboring positions in the modeled outward-open cleft contribute to one low-affinity binding site, whereas arginine 440 located distantly in the cleft is critical for MPP(+) binding to another low-affinity site. Comparing MPP(+) binding with MPP(+) transport suggests that the low-affinity sites are involved in MPP(+) transport, whereas high-affinity MPP(+) binding influences transport allosterically. The data will be helpful in the interpretation of future crystal structures and provides a rationale for future in vitro testing that is more sophisticated and reliable, leading to the generation of pharmacophore models with high predictive power.

@article{keller2019organic, abstract = {Organic cation transporters OCT1 (SLC22A1) and OCT2 (SLC22A2) are critically involved in absorption and excretion of diverse cationic drugs. Because drug-drug interactions at these transporters may induce adverse drug effects in patients, in vitro testing during drug development for interaction with the human transporters is mandatory. Recent data performed with rat OCT1 (rOCT1) suggest that currently performed in vitro tests assuming one polyspecific binding site are insufficient. Here we measured the binding and transport of model substrate 1-methyl-4-phenylpyridinium(+) (MPP(+)) by cell-free-expressed fusion proteins of rOCT1 and rOCT1 mutants with green fluorescent protein that had been reconstituted into nanodiscs or proteoliposomes. The nanodiscs were formed with major scaffold protein (MSP) and different phospholipids, whereas the proteoliposomes were formed with a mixture of cholesterol, phosphatidylserine, and phosphatidylcholine. In nanodiscs formed with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine or cholesterol, phosphatidylserine, and phosphatidylcholine, two low-affinity MPP(+) binding sites and one high-affinity MPP(+) binding site per transporter monomer were determined. Mutagenesis revealed that tryptophan 218 and aspartate 475 in neighboring positions in the modeled outward-open cleft contribute to one low-affinity binding site, whereas arginine 440 located distantly in the cleft is critical for MPP(+) binding to another low-affinity site. Comparing MPP(+) binding with MPP(+) transport suggests that the low-affinity sites are involved in MPP(+) transport, whereas high-affinity MPP(+) binding influences transport allosterically. The data will be helpful in the interpretation of future crystal structures and provides a rationale for future in vitro testing that is more sophisticated and reliable, leading to the generation of pharmacophore models with high predictive power.}, author = {Keller, T. and Gorboulev, V. and Mueller, T. D. and Dotsch, V. and Bernhard, F. and Koepsell, H.}, journal = {Mol Pharmacol}, keywords = {uni_network}, note = {Keller, Thorsten Gorboulev, Valentin Mueller, Thomas D Dotsch, Volker Bernhard, Frank Koepsell, Hermann eng Research Support, Non-U.S. Gov't 2018/11/10 Mol Pharmacol. 2019 Feb;95(2):169-182. doi: 10.1124/mol.118.113498. Epub 2018 Nov 8.}, number = 2, pages = {169-182}, title = {Rat Organic Cation Transporter 1 Contains Three Binding Sites for Substrate 1-Methyl-4-phenylpyridinium per Monomer}, type = {Journal Article}, volume = 95, year = 2019 }

%0 Journal Article %1 keller2019organic %A Keller, T. %A Gorboulev, V. %A Mueller, T. D. %A Dotsch, V. %A Bernhard, F. %A Koepsell, H. %D 2019 %J Mol Pharmacol %N 2 %P 169-182 %R 10.1124/mol.118.113498 %T Rat Organic Cation Transporter 1 Contains Three Binding Sites for Substrate 1-Methyl-4-phenylpyridinium per Monomer %U https://www.ncbi.nlm.nih.gov/pubmed/30409791https://molpharm.aspetjournals.org/content/molpharm/95/2/169.full.pdf %V 95 %X Organic cation transporters OCT1 (SLC22A1) and OCT2 (SLC22A2) are critically involved in absorption and excretion of diverse cationic drugs. Because drug-drug interactions at these transporters may induce adverse drug effects in patients, in vitro testing during drug development for interaction with the human transporters is mandatory. Recent data performed with rat OCT1 (rOCT1) suggest that currently performed in vitro tests assuming one polyspecific binding site are insufficient. Here we measured the binding and transport of model substrate 1-methyl-4-phenylpyridinium(+) (MPP(+)) by cell-free-expressed fusion proteins of rOCT1 and rOCT1 mutants with green fluorescent protein that had been reconstituted into nanodiscs or proteoliposomes. The nanodiscs were formed with major scaffold protein (MSP) and different phospholipids, whereas the proteoliposomes were formed with a mixture of cholesterol, phosphatidylserine, and phosphatidylcholine. In nanodiscs formed with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine or cholesterol, phosphatidylserine, and phosphatidylcholine, two low-affinity MPP(+) binding sites and one high-affinity MPP(+) binding site per transporter monomer were determined. Mutagenesis revealed that tryptophan 218 and aspartate 475 in neighboring positions in the modeled outward-open cleft contribute to one low-affinity binding site, whereas arginine 440 located distantly in the cleft is critical for MPP(+) binding to another low-affinity site. Comparing MPP(+) binding with MPP(+) transport suggests that the low-affinity sites are involved in MPP(+) transport, whereas high-affinity MPP(+) binding influences transport allosterically. The data will be helpful in the interpretation of future crystal structures and provides a rationale for future in vitro testing that is more sophisticated and reliable, leading to the generation of pharmacophore models with high predictive power.
Effects of temperature on the cuticular transpiration barrier of two desert plants with water-spender and water-saver strategies. Bueno, A.; Alfarhan, A.; Arand, K.; Burghardt, M.; Deininger, A. C.; Hedrich, R.; Leide, J.; Seufert, P.; Staiger, S.; Riederer, M. In J Exp Bot, 70(5), pp. 1613–1625. 2019.
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The efficacy of the cuticular transpiration barrier and its resistance to elevated temperatures are significantly higher in a typical water-saver than in a water-spender plant growing in hot desert.

@article{bueno2019effects, abstract = {The efficacy of the cuticular transpiration barrier and its resistance to elevated temperatures are significantly higher in a typical water-saver than in a water-spender plant growing in hot desert.}, author = {Bueno, A. and Alfarhan, A. and Arand, K. and Burghardt, M. and Deininger, A. C. and Hedrich, R. and Leide, J. and Seufert, P. and Staiger, S. and Riederer, M.}, journal = {J Exp Bot}, keywords = {Citrullus}, note = {Bueno, Amauri Alfarhan, Ahmed Arand, Katja Burghardt, Markus Deininger, Ann-Christin Hedrich, Rainer Leide, Jana Seufert, Pascal Staiger, Simona Riederer, Markus eng Research Support, Non-U.S. Gov't England 2019/02/05 J Exp Bot. 2019 Mar 11;70(5):1613-1625. doi: 10.1093/jxb/erz018.}, number = 5, pages = {1613-1625}, title = {Effects of temperature on the cuticular transpiration barrier of two desert plants with water-spender and water-saver strategies}, type = {Journal Article}, volume = 70, year = 2019 }

%0 Journal Article %1 bueno2019effects %A Bueno, A. %A Alfarhan, A. %A Arand, K. %A Burghardt, M. %A Deininger, A. C. %A Hedrich, R. %A Leide, J. %A Seufert, P. %A Staiger, S. %A Riederer, M. %D 2019 %J J Exp Bot %N 5 %P 1613-1625 %R 10.1093/jxb/erz018 %T Effects of temperature on the cuticular transpiration barrier of two desert plants with water-spender and water-saver strategies %U https://www.ncbi.nlm.nih.gov/pubmed/30715440https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6416792/pdf/erz018.pdf %V 70 %X The efficacy of the cuticular transpiration barrier and its resistance to elevated temperatures are significantly higher in a typical water-saver than in a water-spender plant growing in hot desert.
Acquiring Control: The Evolution of Stomatal Signalling Pathways. Sussmilch, F. C.; Schultz, J.; Hedrich, R.; Roelfsema, M. R. G. In Trends Plant Sci, 24(4), pp. 342–351. 2019.
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In vascular plants, stomata balance two opposing functions: they open to facilitate CO(2) uptake and close to prevent excessive water loss. Here, we discuss the evolution of three major signalling pathways that are known to control stomatal movements in angiosperms in response to light, CO(2), and abscisic acid (ABA). We examine the evolutionary origins of key signalling genes involved in these pathways, and compare their expression patterns between an angiosperm and moss. We propose that variation in stomatal sensitivity to stimuli between plant groups are rooted in differences in: (i) gene presence/absence, (ii) specificity of gene spatial expression pattern, and (iii) protein characteristics and functional interactions.

@article{sussmilch2019acquiring, abstract = {In vascular plants, stomata balance two opposing functions: they open to facilitate CO(2) uptake and close to prevent excessive water loss. Here, we discuss the evolution of three major signalling pathways that are known to control stomatal movements in angiosperms in response to light, CO(2), and abscisic acid (ABA). We examine the evolutionary origins of key signalling genes involved in these pathways, and compare their expression patterns between an angiosperm and moss. We propose that variation in stomatal sensitivity to stimuli between plant groups are rooted in differences in: (i) gene presence/absence, (ii) specificity of gene spatial expression pattern, and (iii) protein characteristics and functional interactions.}, author = {Sussmilch, F. C. and Schultz, J. and Hedrich, R. and Roelfsema, M. R. G.}, journal = {Trends Plant Sci}, keywords = {uni_network}, note = {Sussmilch, Frances C Schultz, Jorg Hedrich, Rainer Roelfsema, M Rob G eng Research Support, Non-U.S. Gov't Review England 2019/02/25 Trends Plant Sci. 2019 Apr;24(4):342-351. doi: 10.1016/j.tplants.2019.01.002. Epub 2019 Feb 20.}, number = 4, pages = {342-351}, title = {Acquiring Control: The Evolution of Stomatal Signalling Pathways}, type = {Journal Article}, volume = 24, year = 2019 }

%0 Journal Article %1 sussmilch2019acquiring %A Sussmilch, F. C. %A Schultz, J. %A Hedrich, R. %A Roelfsema, M. R. G. %D 2019 %J Trends Plant Sci %N 4 %P 342-351 %R 10.1016/j.tplants.2019.01.002 %T Acquiring Control: The Evolution of Stomatal Signalling Pathways %U https://www.ncbi.nlm.nih.gov/pubmed/30797685 %V 24 %X In vascular plants, stomata balance two opposing functions: they open to facilitate CO(2) uptake and close to prevent excessive water loss. Here, we discuss the evolution of three major signalling pathways that are known to control stomatal movements in angiosperms in response to light, CO(2), and abscisic acid (ABA). We examine the evolutionary origins of key signalling genes involved in these pathways, and compare their expression patterns between an angiosperm and moss. We propose that variation in stomatal sensitivity to stimuli between plant groups are rooted in differences in: (i) gene presence/absence, (ii) specificity of gene spatial expression pattern, and (iii) protein characteristics and functional interactions.

2018[ to top ]

Collagen I derived recombinant protein microspheres as novel delivery vehicles for bone morphogenetic protein-2. Mumcuoglu, D.; de Miguel, L.; Jekhmane, S.; Siverino, C.; Nickel, J.; Mueller, T. D.; van Leeuwen, J. P.; van Osch, G. J.; Kluijtmans, S. G. In Mater Sci Eng C Mater Biol Appl, 84, pp. 271–280. 2018.
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Bone morphogenetic protein-2 (BMP-2) is a powerful osteoinductive protein; however, there is a need for the development of a safe and efficient BMP-2 release system for bone regeneration therapies. Recombinant extracellular matrix proteins are promising next generation biomaterials since the proteins are well-defined, reproducible and can be tailored for specific applications. In this study, we have developed a novel and versatile BMP-2 delivery system using microspheres from a recombinant protein based on human collagen I (RCP). In general, a two-phase release pattern was observed while the majority of BMP-2 was retained in the microspheres for at least two weeks. Among different parameters studied, the crosslinking and the size of the RCP microspheres changed the in vitro BMP-2 release kinetics significantly. Increasing the chemical crosslinking (hexamethylene diisocyanide) degree decreased the amount of initial burst release (24h) from 23% to 17%. Crosslinking by dehydrothermal treatment further decreased the burst release to 11%. Interestingly, the 50 and 72mum-sized spheres showed a significant decrease in the burst release compared to 207-mum sized spheres. Very importantly, using a reporter cell line, the released BMP-2 was shown to be bioactive. SPR data showed that N-terminal sequence of BMP-2 was important for the binding and retention of BMP-2 and suggested the presence of a specific binding epitope on RCP (K(D): 1.2nM). This study demonstrated that the presented RCP microspheres are promising versatile BMP-2 delivery vehicles.

@article{mumcuoglu2018collagen, abstract = {Bone morphogenetic protein-2 (BMP-2) is a powerful osteoinductive protein; however, there is a need for the development of a safe and efficient BMP-2 release system for bone regeneration therapies. Recombinant extracellular matrix proteins are promising next generation biomaterials since the proteins are well-defined, reproducible and can be tailored for specific applications. In this study, we have developed a novel and versatile BMP-2 delivery system using microspheres from a recombinant protein based on human collagen I (RCP). In general, a two-phase release pattern was observed while the majority of BMP-2 was retained in the microspheres for at least two weeks. Among different parameters studied, the crosslinking and the size of the RCP microspheres changed the in vitro BMP-2 release kinetics significantly. Increasing the chemical crosslinking (hexamethylene diisocyanide) degree decreased the amount of initial burst release (24h) from 23% to 17%. Crosslinking by dehydrothermal treatment further decreased the burst release to 11%. Interestingly, the 50 and 72mum-sized spheres showed a significant decrease in the burst release compared to 207-mum sized spheres. Very importantly, using a reporter cell line, the released BMP-2 was shown to be bioactive. SPR data showed that N-terminal sequence of BMP-2 was important for the binding and retention of BMP-2 and suggested the presence of a specific binding epitope on RCP (K(D): 1.2nM). This study demonstrated that the presented RCP microspheres are promising versatile BMP-2 delivery vehicles.}, author = {Mumcuoglu, D. and de Miguel, L. and Jekhmane, S. and Siverino, C. and Nickel, J. and Mueller, T. D. and van Leeuwen, J. P. and van Osch, G. J. and Kluijtmans, S. G.}, journal = {Mater Sci Eng C Mater Biol Appl}, keywords = {uni_network}, note = {Mumcuoglu, Didem de Miguel, Laura Jekhmane, Shehrazade Siverino, Claudia Nickel, Joachim Mueller, Thomas D van Leeuwen, Johannes P van Osch, Gerjo J Kluijtmans, Sebastiaan G eng Netherlands 2018/03/10 Mater Sci Eng C Mater Biol Appl. 2018 Mar 1;84:271-280. doi: 10.1016/j.msec.2017.11.031. Epub 2017 Dec 1.}, pages = {271-280}, title = {Collagen I derived recombinant protein microspheres as novel delivery vehicles for bone morphogenetic protein-2}, type = {Journal Article}, volume = 84, year = 2018 }

%0 Journal Article %1 mumcuoglu2018collagen %A Mumcuoglu, D. %A de Miguel, L. %A Jekhmane, S. %A Siverino, C. %A Nickel, J. %A Mueller, T. D. %A van Leeuwen, J. P. %A van Osch, G. J. %A Kluijtmans, S. G. %D 2018 %J Mater Sci Eng C Mater Biol Appl %P 271-280 %R 10.1016/j.msec.2017.11.031 %T Collagen I derived recombinant protein microspheres as novel delivery vehicles for bone morphogenetic protein-2 %U https://www.ncbi.nlm.nih.gov/pubmed/29519439https://www.sciencedirect.com/science/article/pii/S0928493117317447?via%3Dihub %V 84 %X Bone morphogenetic protein-2 (BMP-2) is a powerful osteoinductive protein; however, there is a need for the development of a safe and efficient BMP-2 release system for bone regeneration therapies. Recombinant extracellular matrix proteins are promising next generation biomaterials since the proteins are well-defined, reproducible and can be tailored for specific applications. In this study, we have developed a novel and versatile BMP-2 delivery system using microspheres from a recombinant protein based on human collagen I (RCP). In general, a two-phase release pattern was observed while the majority of BMP-2 was retained in the microspheres for at least two weeks. Among different parameters studied, the crosslinking and the size of the RCP microspheres changed the in vitro BMP-2 release kinetics significantly. Increasing the chemical crosslinking (hexamethylene diisocyanide) degree decreased the amount of initial burst release (24h) from 23% to 17%. Crosslinking by dehydrothermal treatment further decreased the burst release to 11%. Interestingly, the 50 and 72mum-sized spheres showed a significant decrease in the burst release compared to 207-mum sized spheres. Very importantly, using a reporter cell line, the released BMP-2 was shown to be bioactive. SPR data showed that N-terminal sequence of BMP-2 was important for the binding and retention of BMP-2 and suggested the presence of a specific binding epitope on RCP (K(D): 1.2nM). This study demonstrated that the presented RCP microspheres are promising versatile BMP-2 delivery vehicles.
Understanding the Molecular Basis of Salt Sequestration in Epidermal Bladder Cells of Chenopodium quinoa. Bohm, J.; Messerer, M.; Muller, H. M.; Scholz-Starke, J.; Gradogna, A.; Scherzer, S.; Maierhofer, T.; Bazihizina, N.; Zhang, H.; Stigloher, C.; Ache, P.; Al-Rasheid, K. A. S.; Mayer, K. F. X.; Shabala, S.; Carpaneto, A.; Haberer, G.; Zhu, J. K.; Hedrich, R. In Curr Biol, 28(19), pp. 3075–3085 e7. 2018.
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Soil salinity is destroying arable land and is considered to be one of the major threats to global food security in the 21st century. Therefore, the ability of naturally salt-tolerant halophyte plants to sequester large quantities of salt in external structures, such as epidermal bladder cells (EBCs), is of great interest. Using Chenopodium quinoa, a pseudo-cereal halophyte of great economic potential, we have shown previously that, upon removal of salt bladders, quinoa becomes salt sensitive. In this work, we analyzed the molecular mechanism underlying the unique salt dumping capabilities of bladder cells in quinoa. The transporters differentially expressed in the EBC transcriptome and functional electrophysiological testing of key EBC transporters in Xenopus oocytes revealed that loading of Na(+) and Cl(-) into EBCs is mediated by a set of tailored plasma and vacuole membrane-based sodium-selective channel and chloride-permeable transporter.

@article{bohm2018understanding, abstract = {Soil salinity is destroying arable land and is considered to be one of the major threats to global food security in the 21st century. Therefore, the ability of naturally salt-tolerant halophyte plants to sequester large quantities of salt in external structures, such as epidermal bladder cells (EBCs), is of great interest. Using Chenopodium quinoa, a pseudo-cereal halophyte of great economic potential, we have shown previously that, upon removal of salt bladders, quinoa becomes salt sensitive. In this work, we analyzed the molecular mechanism underlying the unique salt dumping capabilities of bladder cells in quinoa. The transporters differentially expressed in the EBC transcriptome and functional electrophysiological testing of key EBC transporters in Xenopus oocytes revealed that loading of Na(+) and Cl(-) into EBCs is mediated by a set of tailored plasma and vacuole membrane-based sodium-selective channel and chloride-permeable transporter.}, author = {Bohm, J. and Messerer, M. and Muller, H. M. and Scholz-Starke, J. and Gradogna, A. and Scherzer, S. and Maierhofer, T. and Bazihizina, N. and Zhang, H. and Stigloher, C. and Ache, P. and Al-Rasheid, K. A. S. and Mayer, K. F. X. and Shabala, S. and Carpaneto, A. and Haberer, G. and Zhu, J. K. and Hedrich, R.}, journal = {Curr Biol}, keywords = {uni_network}, note = {Bohm, Jennifer Messerer, Maxim Muller, Heike M Scholz-Starke, Joachim Gradogna, Antonella Scherzer, Sonke Maierhofer, Tobias Bazihizina, Nadia Zhang, Heng Stigloher, Christian Ache, Peter Al-Rasheid, Khaled A S Mayer, Klaus F X Shabala, Sergey Carpaneto, Armando Haberer, Georg Zhu, Jian-Kang Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2018/09/25 Curr Biol. 2018 Oct 8;28(19):3075-3085.e7. doi: 10.1016/j.cub.2018.08.004. Epub 2018 Sep 20.}, number = 19, pages = {3075-3085 e7}, title = {Understanding the Molecular Basis of Salt Sequestration in Epidermal Bladder Cells of Chenopodium quinoa}, type = {Journal Article}, volume = 28, year = 2018 }

%0 Journal Article %1 bohm2018understanding %A Bohm, J. %A Messerer, M. %A Muller, H. M. %A Scholz-Starke, J. %A Gradogna, A. %A Scherzer, S. %A Maierhofer, T. %A Bazihizina, N. %A Zhang, H. %A Stigloher, C. %A Ache, P. %A Al-Rasheid, K. A. S. %A Mayer, K. F. X. %A Shabala, S. %A Carpaneto, A. %A Haberer, G. %A Zhu, J. K. %A Hedrich, R. %D 2018 %J Curr Biol %N 19 %P 3075-3085 e7 %R 10.1016/j.cub.2018.08.004 %T Understanding the Molecular Basis of Salt Sequestration in Epidermal Bladder Cells of Chenopodium quinoa %U https://www.ncbi.nlm.nih.gov/pubmed/30245105 %V 28 %X Soil salinity is destroying arable land and is considered to be one of the major threats to global food security in the 21st century. Therefore, the ability of naturally salt-tolerant halophyte plants to sequester large quantities of salt in external structures, such as epidermal bladder cells (EBCs), is of great interest. Using Chenopodium quinoa, a pseudo-cereal halophyte of great economic potential, we have shown previously that, upon removal of salt bladders, quinoa becomes salt sensitive. In this work, we analyzed the molecular mechanism underlying the unique salt dumping capabilities of bladder cells in quinoa. The transporters differentially expressed in the EBC transcriptome and functional electrophysiological testing of key EBC transporters in Xenopus oocytes revealed that loading of Na(+) and Cl(-) into EBCs is mediated by a set of tailored plasma and vacuole membrane-based sodium-selective channel and chloride-permeable transporter.
The unusual rainbow trout sex determination gene hijacked the canonical vertebrate gonadal differentiation pathway. Bertho, S.; Herpin, A.; Branthonne, A.; Jouanno, E.; Yano, A.; Nicol, B.; Muller, T.; Pannetier, M.; Pailhoux, E.; Miwa, M.; Yoshizaki, G.; Schartl, M.; Guiguen, Y. In Proc Natl Acad Sci U S A, 115(50), pp. 12781–12786. 2018.
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Evolutionary novelties require rewiring of transcriptional networks and/or the evolution of new gene functions. Sex determination (SD), one of the most plastic evolutionary processes, requires such novelties. Studies on the evolution of vertebrate SD revealed that new master SD genes are generally recruited from genes involved in the downstream SD regulatory genetic network. Only a single exception to this rule is currently known in vertebrates: the intriguing case of the salmonid master SD gene (sdY), which arose from duplication of an immune-related gene. This exception immediately posed the question of how a gene outside from the classical sex differentiation cascade could acquire its function as a male SD gene. Here we show that SdY became integrated in the classical vertebrate sex differentiation cascade by interacting with the Forkhead box domain of the female-determining transcription factor, Foxl2. In the presence of Foxl2, SdY is translocated to the nucleus where the SdY:Foxl2 complex prevents activation of the aromatase (cyp19a1a) promoter in cooperation with Nr5a1 (Sf1). Hence, by blocking a positive loop of regulation needed for the synthesis of estrogens in the early differentiating gonad, SdY disrupts a preset female differentiation pathway, consequently allowing testicular differentiation to proceed. These results also suggest that the evolution of unusual vertebrate master sex determination genes recruited from outside the classical pathway like sdY is strongly constrained by their ability to interact with the canonical gonadal differentiation pathway.

@article{bertho2018unusual, abstract = {Evolutionary novelties require rewiring of transcriptional networks and/or the evolution of new gene functions. Sex determination (SD), one of the most plastic evolutionary processes, requires such novelties. Studies on the evolution of vertebrate SD revealed that new master SD genes are generally recruited from genes involved in the downstream SD regulatory genetic network. Only a single exception to this rule is currently known in vertebrates: the intriguing case of the salmonid master SD gene (sdY), which arose from duplication of an immune-related gene. This exception immediately posed the question of how a gene outside from the classical sex differentiation cascade could acquire its function as a male SD gene. Here we show that SdY became integrated in the classical vertebrate sex differentiation cascade by interacting with the Forkhead box domain of the female-determining transcription factor, Foxl2. In the presence of Foxl2, SdY is translocated to the nucleus where the SdY:Foxl2 complex prevents activation of the aromatase (cyp19a1a) promoter in cooperation with Nr5a1 (Sf1). Hence, by blocking a positive loop of regulation needed for the synthesis of estrogens in the early differentiating gonad, SdY disrupts a preset female differentiation pathway, consequently allowing testicular differentiation to proceed. These results also suggest that the evolution of unusual vertebrate master sex determination genes recruited from outside the classical pathway like sdY is strongly constrained by their ability to interact with the canonical gonadal differentiation pathway.}, author = {Bertho, S. and Herpin, A. and Branthonne, A. and Jouanno, E. and Yano, A. and Nicol, B. and Muller, T. and Pannetier, M. and Pailhoux, E. and Miwa, M. and Yoshizaki, G. and Schartl, M. and Guiguen, Y.}, journal = {Proc Natl Acad Sci U S A}, keywords = {uni_network}, note = {Bertho, Sylvain Herpin, Amaury Branthonne, Adele Jouanno, Elodie Yano, Ayaka Nicol, Barbara Muller, Thomas Pannetier, Maelle Pailhoux, Eric Miwa, Misako Yoshizaki, Goro Schartl, Manfred Guiguen, Yann eng Research Support, Non-U.S. Gov't 2018/11/23 Proc Natl Acad Sci U S A. 2018 Dec 11;115(50):12781-12786. doi: 10.1073/pnas.1803826115. Epub 2018 Nov 21.}, number = 50, pages = {12781-12786}, title = {The unusual rainbow trout sex determination gene hijacked the canonical vertebrate gonadal differentiation pathway}, type = {Journal Article}, volume = 115, year = 2018 }

%0 Journal Article %1 bertho2018unusual %A Bertho, S. %A Herpin, A. %A Branthonne, A. %A Jouanno, E. %A Yano, A. %A Nicol, B. %A Muller, T. %A Pannetier, M. %A Pailhoux, E. %A Miwa, M. %A Yoshizaki, G. %A Schartl, M. %A Guiguen, Y. %D 2018 %J Proc Natl Acad Sci U S A %N 50 %P 12781-12786 %R 10.1073/pnas.1803826115 %T The unusual rainbow trout sex determination gene hijacked the canonical vertebrate gonadal differentiation pathway %U https://www.ncbi.nlm.nih.gov/pubmed/30463951https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294932/pdf/pnas.201803826.pdf %V 115 %X Evolutionary novelties require rewiring of transcriptional networks and/or the evolution of new gene functions. Sex determination (SD), one of the most plastic evolutionary processes, requires such novelties. Studies on the evolution of vertebrate SD revealed that new master SD genes are generally recruited from genes involved in the downstream SD regulatory genetic network. Only a single exception to this rule is currently known in vertebrates: the intriguing case of the salmonid master SD gene (sdY), which arose from duplication of an immune-related gene. This exception immediately posed the question of how a gene outside from the classical sex differentiation cascade could acquire its function as a male SD gene. Here we show that SdY became integrated in the classical vertebrate sex differentiation cascade by interacting with the Forkhead box domain of the female-determining transcription factor, Foxl2. In the presence of Foxl2, SdY is translocated to the nucleus where the SdY:Foxl2 complex prevents activation of the aromatase (cyp19a1a) promoter in cooperation with Nr5a1 (Sf1). Hence, by blocking a positive loop of regulation needed for the synthesis of estrogens in the early differentiating gonad, SdY disrupts a preset female differentiation pathway, consequently allowing testicular differentiation to proceed. These results also suggest that the evolution of unusual vertebrate master sex determination genes recruited from outside the classical pathway like sdY is strongly constrained by their ability to interact with the canonical gonadal differentiation pathway.
Hepatoprotective potential of Malvaviscus arboreus against carbon tetrachloride-induced liver injury in rats. Abdelhafez, O. H.; Fawzy, M. A.; Fahim, J. R.; Desoukey, S. Y.; Krischke, M.; Mueller, M. J.; Abdelmohsen, U. R. In PLoS One, 13(8), p. e0202362. 2018.
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Malvaviscus arboreus Cav. is a medicinal plant belonging to family Malvaceae with both ethnomedical and culinary value; however, its phytochemical and biological profiles have been scarcely studied. Accordingly, this work was designed to explore the chemical composition and the hepatoprotective potential of M. arboreus against carbon tetrachloride (CCl4)-induced hepatotoxicity. The total extract of the aerial parts and its derived fractions (petroleum ether, dichloromethane, ethyl acetate, and aqueous) were orally administered to rats for six consecutive days, followed by injection of CCl4 (1:1 v/v, in olive oil, 1.5 ml/kg, i.p.) on the next day. Results showed that the ethyl acetate and dichloromethane fractions significantly alleviated liver injury in rats as indicated by the reduced levels of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin (TB), and malondialdehyde (MDA), along with enhancement of the total antioxidant capacities of their livers, with the maximum effects were recorded by the ethyl acetate fraction. Moreover, the protective actions of both fractions were comparable to those of silymarin (100 mg/kg), and have been also substantiated by histopathological evaluations. On the other hand, liquid chromatography-high resolution electrospray ionization mass spectrometry (LC‒HR‒ESI‒MS) metabolomic profiling of the crude extract of M. arboreus aerial parts showed the presence of a variety of phytochemicals, mostly phenolics, whereas the detailed chemical analysis of the most active fraction (i.e. ethyl acetate) resulted in the isolation and identification of six compounds for the first time in the genus, comprising four phenolic acids; beta-resorcylic, caffeic, protocatechuic, and 4-hydroxyphenylacetic acids, in addition to two flavonoids; trifolin and astragalin. Such phenolic principles, together with their probable synergistic antioxidant and liver-protecting properties, seem to contribute to the observed hepatoprotective potential of M. arboreus.

@article{abdelhafez2018hepatoprotective, abstract = {Malvaviscus arboreus Cav. is a medicinal plant belonging to family Malvaceae with both ethnomedical and culinary value; however, its phytochemical and biological profiles have been scarcely studied. Accordingly, this work was designed to explore the chemical composition and the hepatoprotective potential of M. arboreus against carbon tetrachloride (CCl4)-induced hepatotoxicity. The total extract of the aerial parts and its derived fractions (petroleum ether, dichloromethane, ethyl acetate, and aqueous) were orally administered to rats for six consecutive days, followed by injection of CCl4 (1:1 v/v, in olive oil, 1.5 ml/kg, i.p.) on the next day. Results showed that the ethyl acetate and dichloromethane fractions significantly alleviated liver injury in rats as indicated by the reduced levels of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin (TB), and malondialdehyde (MDA), along with enhancement of the total antioxidant capacities of their livers, with the maximum effects were recorded by the ethyl acetate fraction. Moreover, the protective actions of both fractions were comparable to those of silymarin (100 mg/kg), and have been also substantiated by histopathological evaluations. On the other hand, liquid chromatography-high resolution electrospray ionization mass spectrometry (LC‒HR‒ESI‒MS) metabolomic profiling of the crude extract of M. arboreus aerial parts showed the presence of a variety of phytochemicals, mostly phenolics, whereas the detailed chemical analysis of the most active fraction (i.e. ethyl acetate) resulted in the isolation and identification of six compounds for the first time in the genus, comprising four phenolic acids; beta-resorcylic, caffeic, protocatechuic, and 4-hydroxyphenylacetic acids, in addition to two flavonoids; trifolin and astragalin. Such phenolic principles, together with their probable synergistic antioxidant and liver-protecting properties, seem to contribute to the observed hepatoprotective potential of M. arboreus.}, author = {Abdelhafez, O. H. and Fawzy, M. A. and Fahim, J. R. and Desoukey, S. Y. and Krischke, M. and Mueller, M. J. and Abdelmohsen, U. R.}, journal = {PLoS One}, keywords = {Oral}, note = {Abdelhafez, Omnia Hesham Fawzy, Michael Atef Fahim, John Refaat Desoukey, Samar Yehia Krischke, Markus Mueller, Martin J Abdelmohsen, Usama Ramadan eng Research Support, Non-U.S. Gov't 2018/08/24 PLoS One. 2018 Aug 23;13(8):e0202362. doi: 10.1371/journal.pone.0202362. eCollection 2018.}, number = 8, pages = {e0202362}, title = {Hepatoprotective potential of Malvaviscus arboreus against carbon tetrachloride-induced liver injury in rats}, type = {Journal Article}, volume = 13, year = 2018 }

%0 Journal Article %1 abdelhafez2018hepatoprotective %A Abdelhafez, O. H. %A Fawzy, M. A. %A Fahim, J. R. %A Desoukey, S. Y. %A Krischke, M. %A Mueller, M. J. %A Abdelmohsen, U. R. %D 2018 %J PLoS One %N 8 %P e0202362 %R 10.1371/journal.pone.0202362 %T Hepatoprotective potential of Malvaviscus arboreus against carbon tetrachloride-induced liver injury in rats %U https://www.ncbi.nlm.nih.gov/pubmed/30138328https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0202362&type=printable %V 13 %X Malvaviscus arboreus Cav. is a medicinal plant belonging to family Malvaceae with both ethnomedical and culinary value; however, its phytochemical and biological profiles have been scarcely studied. Accordingly, this work was designed to explore the chemical composition and the hepatoprotective potential of M. arboreus against carbon tetrachloride (CCl4)-induced hepatotoxicity. The total extract of the aerial parts and its derived fractions (petroleum ether, dichloromethane, ethyl acetate, and aqueous) were orally administered to rats for six consecutive days, followed by injection of CCl4 (1:1 v/v, in olive oil, 1.5 ml/kg, i.p.) on the next day. Results showed that the ethyl acetate and dichloromethane fractions significantly alleviated liver injury in rats as indicated by the reduced levels of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin (TB), and malondialdehyde (MDA), along with enhancement of the total antioxidant capacities of their livers, with the maximum effects were recorded by the ethyl acetate fraction. Moreover, the protective actions of both fractions were comparable to those of silymarin (100 mg/kg), and have been also substantiated by histopathological evaluations. On the other hand, liquid chromatography-high resolution electrospray ionization mass spectrometry (LC‒HR‒ESI‒MS) metabolomic profiling of the crude extract of M. arboreus aerial parts showed the presence of a variety of phytochemicals, mostly phenolics, whereas the detailed chemical analysis of the most active fraction (i.e. ethyl acetate) resulted in the isolation and identification of six compounds for the first time in the genus, comprising four phenolic acids; beta-resorcylic, caffeic, protocatechuic, and 4-hydroxyphenylacetic acids, in addition to two flavonoids; trifolin and astragalin. Such phenolic principles, together with their probable synergistic antioxidant and liver-protecting properties, seem to contribute to the observed hepatoprotective potential of M. arboreus.
Snf1-RELATED KINASE1-Controlled C/S(1)-bZIP Signaling Activates Alternative Mitochondrial Metabolic Pathways to Ensure Plant Survival in Extended Darkness. Pedrotti, L.; Weiste, C.; Nagele, T.; Wolf, E.; Lorenzin, F.; Dietrich, K.; Mair, A.; Weckwerth, W.; Teige, M.; Baena-Gonzalez, E.; Droge-Laser, W. In Plant Cell, 30(2), pp. 495–509. 2018.
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Sustaining energy homeostasis is of pivotal importance for all living organisms. In Arabidopsis thaliana, evolutionarily conserved SnRK1 kinases (Snf1-RELATED KINASE1) control metabolic adaptation during low energy stress. To unravel starvation-induced transcriptional mechanisms, we performed transcriptome studies of inducible knockdown lines and found that S(1)-basic leucine zipper transcription factors (S(1)-bZIPs) control a defined subset of genes downstream of SnRK1. For example, S(1)-bZIPs coordinate the expression of genes involved in branched-chain amino acid catabolism, which constitutes an alternative mitochondrial respiratory pathway that is crucial for plant survival during starvation. Molecular analyses defined S(1)-bZIPs as SnRK1-dependent regulators that directly control transcription via binding to G-box promoter elements. Moreover, SnRK1 triggers phosphorylation of group C-bZIPs and the formation of C/S(1)-heterodimers and, thus, the recruitment of SnRK1 directly to target promoters. Subsequently, the C/S(1)-bZIP-SnRK1 complex interacts with the histone acetylation machinery to remodel chromatin and facilitate transcription. Taken together, this work reveals molecular mechanisms underlying how energy deprivation is transduced to reprogram gene expression, leading to metabolic adaptation upon stress.

@article{pedrotti2018snf1related, abstract = {Sustaining energy homeostasis is of pivotal importance for all living organisms. In Arabidopsis thaliana, evolutionarily conserved SnRK1 kinases (Snf1-RELATED KINASE1) control metabolic adaptation during low energy stress. To unravel starvation-induced transcriptional mechanisms, we performed transcriptome studies of inducible knockdown lines and found that S(1)-basic leucine zipper transcription factors (S(1)-bZIPs) control a defined subset of genes downstream of SnRK1. For example, S(1)-bZIPs coordinate the expression of genes involved in branched-chain amino acid catabolism, which constitutes an alternative mitochondrial respiratory pathway that is crucial for plant survival during starvation. Molecular analyses defined S(1)-bZIPs as SnRK1-dependent regulators that directly control transcription via binding to G-box promoter elements. Moreover, SnRK1 triggers phosphorylation of group C-bZIPs and the formation of C/S(1)-heterodimers and, thus, the recruitment of SnRK1 directly to target promoters. Subsequently, the C/S(1)-bZIP-SnRK1 complex interacts with the histone acetylation machinery to remodel chromatin and facilitate transcription. Taken together, this work reveals molecular mechanisms underlying how energy deprivation is transduced to reprogram gene expression, leading to metabolic adaptation upon stress.}, author = {Pedrotti, L. and Weiste, C. and Nagele, T. and Wolf, E. and Lorenzin, F. and Dietrich, K. and Mair, A. and Weckwerth, W. and Teige, M. and Baena-Gonzalez, E. and Droge-Laser, W.}, journal = {Plant Cell}, keywords = {Physiological}, note = {Pedrotti, Lorenzo Weiste, Christoph Nagele, Thomas Wolf, Elmar Lorenzin, Francesca Dietrich, Katrin Mair, Andrea Weckwerth, Wolfram Teige, Markus Baena-Gonzalez, Elena Droge-Laser, Wolfgang eng P 28491/FWF_/Austrian Science Fund FWF/Austria Research Support, Non-U.S. Gov't England 2018/01/20 Plant Cell. 2018 Feb;30(2):495-509. doi: 10.1105/tpc.17.00414. Epub 2018 Jan 18.}, number = 2, pages = {495-509}, title = {Snf1-RELATED KINASE1-Controlled C/S(1)-bZIP Signaling Activates Alternative Mitochondrial Metabolic Pathways to Ensure Plant Survival in Extended Darkness}, type = {Journal Article}, volume = 30, year = 2018 }

%0 Journal Article %1 pedrotti2018snf1related %A Pedrotti, L. %A Weiste, C. %A Nagele, T. %A Wolf, E. %A Lorenzin, F. %A Dietrich, K. %A Mair, A. %A Weckwerth, W. %A Teige, M. %A Baena-Gonzalez, E. %A Droge-Laser, W. %D 2018 %J Plant Cell %N 2 %P 495-509 %R 10.1105/tpc.17.00414 %T Snf1-RELATED KINASE1-Controlled C/S(1)-bZIP Signaling Activates Alternative Mitochondrial Metabolic Pathways to Ensure Plant Survival in Extended Darkness %U https://www.ncbi.nlm.nih.gov/pubmed/29348240https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5868691/pdf/PC_TPC2017RA00414R1.pdf %V 30 %X Sustaining energy homeostasis is of pivotal importance for all living organisms. In Arabidopsis thaliana, evolutionarily conserved SnRK1 kinases (Snf1-RELATED KINASE1) control metabolic adaptation during low energy stress. To unravel starvation-induced transcriptional mechanisms, we performed transcriptome studies of inducible knockdown lines and found that S(1)-basic leucine zipper transcription factors (S(1)-bZIPs) control a defined subset of genes downstream of SnRK1. For example, S(1)-bZIPs coordinate the expression of genes involved in branched-chain amino acid catabolism, which constitutes an alternative mitochondrial respiratory pathway that is crucial for plant survival during starvation. Molecular analyses defined S(1)-bZIPs as SnRK1-dependent regulators that directly control transcription via binding to G-box promoter elements. Moreover, SnRK1 triggers phosphorylation of group C-bZIPs and the formation of C/S(1)-heterodimers and, thus, the recruitment of SnRK1 directly to target promoters. Subsequently, the C/S(1)-bZIP-SnRK1 complex interacts with the histone acetylation machinery to remodel chromatin and facilitate transcription. Taken together, this work reveals molecular mechanisms underlying how energy deprivation is transduced to reprogram gene expression, leading to metabolic adaptation upon stress.
Site-Directed Immobilization of Bone Morphogenetic Protein 2 to Solid Surfaces by Click Chemistry. Siverino, C.; Tabisz, B.; Luhmann, T.; Meinel, L.; Muller, T.; Walles, H.; Nickel, J. In J Vis Exp, (133). 2018.
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Different therapeutic strategies for the treatment of non-healing long bone defects have been intensively investigated. Currently used treatments present several limitations that have led to the use of biomaterials in combination with osteogenic growth factors, such as bone morphogenetic proteins (BMPs). Commonly used absorption or encapsulation methods require supra-physiological amounts of BMP2, typically resulting in a so-called initial burst release effect that provokes several severe adverse side effects. A possible strategy to overcome these problems would be to covalently couple the protein to the scaffold. Moreover, coupling should be performed in a site-specific manner in order to guarantee a reproducible product outcome. Therefore, we created a BMP2 variant, in which an artificial amino acid (propargyl-L-lysine) was introduced into the mature part of the BMP2 protein by codon usage expansion (BMP2-K3Plk). BMP2-K3Plk was coupled to functionalized beads through copper catalyzed azide-alkyne cycloaddition (CuAAC). The biological activity of the coupled BMP2-K3Plk was proven in vitro and the osteogenic activity of the BMP2-K3Plk-functionalized beads was proven in cell based assays. The functionalized beads in contact with C2C12 cells were able to induce alkaline phosphatase (ALP) expression in locally restricted proximity of the bead. Thus, by this technique, functionalized scaffolds can be produced that can trigger cell differentiation towards an osteogenic lineage. Additionally, lower BMP2 doses are sufficient due to the controlled orientation of site-directed coupled BMP2. With this method, BMPs are always exposed to their receptors on the cell surface in the appropriate orientation, which is not the case if the factors are coupled via non-site-directed coupling techniques. The product outcome is highly controllable and, thus, results in materials with homogeneous properties, improving their applicability for the repair of critical size bone defects.

@article{siverino2018sitedirected, abstract = {Different therapeutic strategies for the treatment of non-healing long bone defects have been intensively investigated. Currently used treatments present several limitations that have led to the use of biomaterials in combination with osteogenic growth factors, such as bone morphogenetic proteins (BMPs). Commonly used absorption or encapsulation methods require supra-physiological amounts of BMP2, typically resulting in a so-called initial burst release effect that provokes several severe adverse side effects. A possible strategy to overcome these problems would be to covalently couple the protein to the scaffold. Moreover, coupling should be performed in a site-specific manner in order to guarantee a reproducible product outcome. Therefore, we created a BMP2 variant, in which an artificial amino acid (propargyl-L-lysine) was introduced into the mature part of the BMP2 protein by codon usage expansion (BMP2-K3Plk). BMP2-K3Plk was coupled to functionalized beads through copper catalyzed azide-alkyne cycloaddition (CuAAC). The biological activity of the coupled BMP2-K3Plk was proven in vitro and the osteogenic activity of the BMP2-K3Plk-functionalized beads was proven in cell based assays. The functionalized beads in contact with C2C12 cells were able to induce alkaline phosphatase (ALP) expression in locally restricted proximity of the bead. Thus, by this technique, functionalized scaffolds can be produced that can trigger cell differentiation towards an osteogenic lineage. Additionally, lower BMP2 doses are sufficient due to the controlled orientation of site-directed coupled BMP2. With this method, BMPs are always exposed to their receptors on the cell surface in the appropriate orientation, which is not the case if the factors are coupled via non-site-directed coupling techniques. The product outcome is highly controllable and, thus, results in materials with homogeneous properties, improving their applicability for the repair of critical size bone defects.}, author = {Siverino, C. and Tabisz, B. and Luhmann, T. and Meinel, L. and Muller, T. and Walles, H. and Nickel, J.}, journal = {J Vis Exp}, keywords = {uni_network}, note = {Siverino, Claudia Tabisz, Barbara Luhmann, Tessa Meinel, Lorenz Muller, Thomas Walles, Heike Nickel, Joachim eng Video-Audio Media 2018/04/17 J Vis Exp. 2018 Mar 29;(133):56616. doi: 10.3791/56616.}, number = 133, title = {Site-Directed Immobilization of Bone Morphogenetic Protein 2 to Solid Surfaces by Click Chemistry}, type = {Journal Article}, year = 2018 }

%0 Journal Article %1 siverino2018sitedirected %A Siverino, C. %A Tabisz, B. %A Luhmann, T. %A Meinel, L. %A Muller, T. %A Walles, H. %A Nickel, J. %D 2018 %J J Vis Exp %N 133 %R 10.3791/56616 %T Site-Directed Immobilization of Bone Morphogenetic Protein 2 to Solid Surfaces by Click Chemistry %U https://www.ncbi.nlm.nih.gov/pubmed/29658921https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5933278/pdf/jove-133-56616.pdf %X Different therapeutic strategies for the treatment of non-healing long bone defects have been intensively investigated. Currently used treatments present several limitations that have led to the use of biomaterials in combination with osteogenic growth factors, such as bone morphogenetic proteins (BMPs). Commonly used absorption or encapsulation methods require supra-physiological amounts of BMP2, typically resulting in a so-called initial burst release effect that provokes several severe adverse side effects. A possible strategy to overcome these problems would be to covalently couple the protein to the scaffold. Moreover, coupling should be performed in a site-specific manner in order to guarantee a reproducible product outcome. Therefore, we created a BMP2 variant, in which an artificial amino acid (propargyl-L-lysine) was introduced into the mature part of the BMP2 protein by codon usage expansion (BMP2-K3Plk). BMP2-K3Plk was coupled to functionalized beads through copper catalyzed azide-alkyne cycloaddition (CuAAC). The biological activity of the coupled BMP2-K3Plk was proven in vitro and the osteogenic activity of the BMP2-K3Plk-functionalized beads was proven in cell based assays. The functionalized beads in contact with C2C12 cells were able to induce alkaline phosphatase (ALP) expression in locally restricted proximity of the bead. Thus, by this technique, functionalized scaffolds can be produced that can trigger cell differentiation towards an osteogenic lineage. Additionally, lower BMP2 doses are sufficient due to the controlled orientation of site-directed coupled BMP2. With this method, BMPs are always exposed to their receptors on the cell surface in the appropriate orientation, which is not the case if the factors are coupled via non-site-directed coupling techniques. The product outcome is highly controllable and, thus, results in materials with homogeneous properties, improving their applicability for the repair of critical size bone defects.
Bioresponsive release of insulin-like growth factor-I from its PEGylated conjugate. Braun, A. C.; Gutmann, M.; Mueller, T. D.; Luhmann, T.; Meinel, L. In J Control Release, 279, pp. 17–28. 2018.
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PEGylation of protein ligands, the attachment of polyethylene glycol (PEG) polymers to a therapeutic protein, increases therapeutics' half-life but frequently comes at the cost of reduced bioactivity. We are now presenting a bioinspired strategy leading out of this dilemma. To this end, we selected a position within insulin-like growth factor I (IGF-I) for decoration with a PEG(30kDa)-modified protease-sensitive peptide linker (PSL) using a combination of enzymatic and chemical bioorthogonal coupling strategies. The PSL sequence responded to matrix metalloproteinases (MMP) to provide a targeted release in diseased tissue. The IGF-PSL-PEG conjugate had different binding protein affinity, cell proliferation, and endocytosis patterns as compared to the wild type. Exposure of the conjugate to elevated levels of activated MMPs, as present in inflamed tissues, fully reestablished the wild type properties through effective PSL cleavage. In conclusion, this bioinspired approach provided a blueprint for PEGylated therapeutics combining the pharmacokinetic advantages of PEGylation, while locally restoring the full suite of biological potential of therapeutics.

@article{braun2018bioresponsive, abstract = {PEGylation of protein ligands, the attachment of polyethylene glycol (PEG) polymers to a therapeutic protein, increases therapeutics' half-life but frequently comes at the cost of reduced bioactivity. We are now presenting a bioinspired strategy leading out of this dilemma. To this end, we selected a position within insulin-like growth factor I (IGF-I) for decoration with a PEG(30kDa)-modified protease-sensitive peptide linker (PSL) using a combination of enzymatic and chemical bioorthogonal coupling strategies. The PSL sequence responded to matrix metalloproteinases (MMP) to provide a targeted release in diseased tissue. The IGF-PSL-PEG conjugate had different binding protein affinity, cell proliferation, and endocytosis patterns as compared to the wild type. Exposure of the conjugate to elevated levels of activated MMPs, as present in inflamed tissues, fully reestablished the wild type properties through effective PSL cleavage. In conclusion, this bioinspired approach provided a blueprint for PEGylated therapeutics combining the pharmacokinetic advantages of PEGylation, while locally restoring the full suite of biological potential of therapeutics.}, author = {Braun, A. C. and Gutmann, M. and Mueller, T. D. and Luhmann, T. and Meinel, L.}, journal = {J Control Release}, keywords = {uni_network}, note = {Braun, Alexandra C Gutmann, Marcus Mueller, Thomas D Luhmann, Tessa Meinel, Lorenz eng Comparative Study Research Support, Non-U.S. Gov't Netherlands 2018/04/11 J Control Release. 2018 Jun 10;279:17-28. doi: 10.1016/j.jconrel.2018.04.009. Epub 2018 Apr 7.}, pages = {17-28}, title = {Bioresponsive release of insulin-like growth factor-I from its PEGylated conjugate}, type = {Journal Article}, volume = 279, year = 2018 }

%0 Journal Article %1 braun2018bioresponsive %A Braun, A. C. %A Gutmann, M. %A Mueller, T. D. %A Luhmann, T. %A Meinel, L. %D 2018 %J J Control Release %P 17-28 %R 10.1016/j.jconrel.2018.04.009 %T Bioresponsive release of insulin-like growth factor-I from its PEGylated conjugate %U https://www.ncbi.nlm.nih.gov/pubmed/29634992 %V 279 %X PEGylation of protein ligands, the attachment of polyethylene glycol (PEG) polymers to a therapeutic protein, increases therapeutics' half-life but frequently comes at the cost of reduced bioactivity. We are now presenting a bioinspired strategy leading out of this dilemma. To this end, we selected a position within insulin-like growth factor I (IGF-I) for decoration with a PEG(30kDa)-modified protease-sensitive peptide linker (PSL) using a combination of enzymatic and chemical bioorthogonal coupling strategies. The PSL sequence responded to matrix metalloproteinases (MMP) to provide a targeted release in diseased tissue. The IGF-PSL-PEG conjugate had different binding protein affinity, cell proliferation, and endocytosis patterns as compared to the wild type. Exposure of the conjugate to elevated levels of activated MMPs, as present in inflamed tissues, fully reestablished the wild type properties through effective PSL cleavage. In conclusion, this bioinspired approach provided a blueprint for PEGylated therapeutics combining the pharmacokinetic advantages of PEGylation, while locally restoring the full suite of biological potential of therapeutics.
Assay Conditions Influence Affinities of Rat Organic Cation Transporter 1: Analysis of Mutagenesis in the Modeled Outward-Facing Cleft by Measuring Effects of Substrates and Inhibitors on Initial Uptake. Gorboulev, V.; Rehman, S.; Albert, C. M.; Roth, U.; Meyer, M. J.; Tzvetkov, M. V.; Mueller, T. D.; Koepsell, H. In Mol Pharmacol, 93(4), pp. 402–415. 2018.
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The effects of mutations in the modeled outward-open cleft of rat organic cation transporter 1 (rOCT1) on affinities of substrates and inhibitors were investigated. Human embryonic kidney 293 cells were stably transfected with rOCT1 or rOCT1 mutants, and uptake of the substrates 1-methyl-4-phenylpyridinium(+) (MPP(+)) and tetraethylammonium(+) (TEA(+)) or inhibition of MPP(+) uptake by the nontransported inhibitors tetrabutylammonium(+) (TBuA(+)), tetrapentylammonium(+) (TPeA(+)), and corticosterone was measured. Uptake measurements were performed on confluent cell layers using a 2-minute incubation or in dissociated cells using incubation times of 1, 5, or 10 seconds. With both methods, different apparent Michaelis-Menten constant (K(m)) values, different IC(50) values, and varying effects of mutations were determined. In addition, varying IC(50) values for the inhibition of MPP(+) uptake and varying effects of mutations were obtained when different MPP(+) concentrations far below the apparent K(m) value were used for uptake measurements. Eleven mutations were investigated by measuring initial uptake in dissociated cells and employing 0.1 microM MPP(+) for uptake during inhibition experiments. Altered affinities for substrates and/or inhibitors were observed when Phe160, Trp218, Arg440, Leu447, and Asp475 were mutated. The mutations resulted in changes of apparent K(m) values for TEA(+) and/or MPP(+) Mutation of Trp218 and Asp475 led to altered IC(50) values for TBuA(+), TPeA(+), and corticosterone, whereas the mutation of Phe160 and Leu447 changed the IC(50) values for two inhibitors. Thereby amino acids in the outward-facing conformation of rOCT1 could be identified that interact with structurally different inhibitors and probably also with different substrates.

@article{gorboulev2018assay, abstract = {The effects of mutations in the modeled outward-open cleft of rat organic cation transporter 1 (rOCT1) on affinities of substrates and inhibitors were investigated. Human embryonic kidney 293 cells were stably transfected with rOCT1 or rOCT1 mutants, and uptake of the substrates 1-methyl-4-phenylpyridinium(+) (MPP(+)) and tetraethylammonium(+) (TEA(+)) or inhibition of MPP(+) uptake by the nontransported inhibitors tetrabutylammonium(+) (TBuA(+)), tetrapentylammonium(+) (TPeA(+)), and corticosterone was measured. Uptake measurements were performed on confluent cell layers using a 2-minute incubation or in dissociated cells using incubation times of 1, 5, or 10 seconds. With both methods, different apparent Michaelis-Menten constant (K(m)) values, different IC(50) values, and varying effects of mutations were determined. In addition, varying IC(50) values for the inhibition of MPP(+) uptake and varying effects of mutations were obtained when different MPP(+) concentrations far below the apparent K(m) value were used for uptake measurements. Eleven mutations were investigated by measuring initial uptake in dissociated cells and employing 0.1 microM MPP(+) for uptake during inhibition experiments. Altered affinities for substrates and/or inhibitors were observed when Phe160, Trp218, Arg440, Leu447, and Asp475 were mutated. The mutations resulted in changes of apparent K(m) values for TEA(+) and/or MPP(+) Mutation of Trp218 and Asp475 led to altered IC(50) values for TBuA(+), TPeA(+), and corticosterone, whereas the mutation of Phe160 and Leu447 changed the IC(50) values for two inhibitors. Thereby amino acids in the outward-facing conformation of rOCT1 could be identified that interact with structurally different inhibitors and probably also with different substrates.}, author = {Gorboulev, V. and Rehman, S. and Albert, C. M. and Roth, U. and Meyer, M. J. and Tzvetkov, M. V. and Mueller, T. D. and Koepsell, H.}, journal = {Mol Pharmacol}, keywords = {1-Methyl-4-phenylpyridinium/metabolism/pharmacology}, note = {Gorboulev, Valentin Rehman, Saba Albert, Christoph M Roth, Ursula Meyer, Marleen J Tzvetkov, Mladen V Mueller, Thomas D Koepsell, Hermann eng Research Support, Non-U.S. Gov't 2018/01/18 Mol Pharmacol. 2018 Apr;93(4):402-415. doi: 10.1124/mol.117.110767. Epub 2018 Jan 16.}, number = 4, pages = {402-415}, title = {Assay Conditions Influence Affinities of Rat Organic Cation Transporter 1: Analysis of Mutagenesis in the Modeled Outward-Facing Cleft by Measuring Effects of Substrates and Inhibitors on Initial Uptake}, type = {Journal Article}, volume = 93, year = 2018 }

%0 Journal Article %1 gorboulev2018assay %A Gorboulev, V. %A Rehman, S. %A Albert, C. M. %A Roth, U. %A Meyer, M. J. %A Tzvetkov, M. V. %A Mueller, T. D. %A Koepsell, H. %D 2018 %J Mol Pharmacol %N 4 %P 402-415 %R 10.1124/mol.117.110767 %T Assay Conditions Influence Affinities of Rat Organic Cation Transporter 1: Analysis of Mutagenesis in the Modeled Outward-Facing Cleft by Measuring Effects of Substrates and Inhibitors on Initial Uptake %U https://www.ncbi.nlm.nih.gov/pubmed/29339398https://molpharm.aspetjournals.org/content/molpharm/93/4/402.full.pdf %V 93 %X The effects of mutations in the modeled outward-open cleft of rat organic cation transporter 1 (rOCT1) on affinities of substrates and inhibitors were investigated. Human embryonic kidney 293 cells were stably transfected with rOCT1 or rOCT1 mutants, and uptake of the substrates 1-methyl-4-phenylpyridinium(+) (MPP(+)) and tetraethylammonium(+) (TEA(+)) or inhibition of MPP(+) uptake by the nontransported inhibitors tetrabutylammonium(+) (TBuA(+)), tetrapentylammonium(+) (TPeA(+)), and corticosterone was measured. Uptake measurements were performed on confluent cell layers using a 2-minute incubation or in dissociated cells using incubation times of 1, 5, or 10 seconds. With both methods, different apparent Michaelis-Menten constant (K(m)) values, different IC(50) values, and varying effects of mutations were determined. In addition, varying IC(50) values for the inhibition of MPP(+) uptake and varying effects of mutations were obtained when different MPP(+) concentrations far below the apparent K(m) value were used for uptake measurements. Eleven mutations were investigated by measuring initial uptake in dissociated cells and employing 0.1 microM MPP(+) for uptake during inhibition experiments. Altered affinities for substrates and/or inhibitors were observed when Phe160, Trp218, Arg440, Leu447, and Asp475 were mutated. The mutations resulted in changes of apparent K(m) values for TEA(+) and/or MPP(+) Mutation of Trp218 and Asp475 led to altered IC(50) values for TBuA(+), TPeA(+), and corticosterone, whereas the mutation of Phe160 and Leu447 changed the IC(50) values for two inhibitors. Thereby amino acids in the outward-facing conformation of rOCT1 could be identified that interact with structurally different inhibitors and probably also with different substrates.
High V-PPase activity is beneficial under high salt loads, but detrimental without salinity. Graus, D.; Konrad, K. R.; Bemm, F.; Patir Nebioglu, M. G.; Lorey, C.; Duscha, K.; Guthoff, T.; Herrmann, J.; Ferjani, A.; Cuin, T. A.; Roelfsema, M. R. G.; Schumacher, K.; Neuhaus, H. E.; Marten, I.; Hedrich, R. In New Phytol, 219(4), pp. 1421–1432. 2018.
- [ Abstract ]
- [ BibTeX ]
- [ EndNote ]
- [ URL ]
- [ DOI ]
The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H(+) -ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PP(i) hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na(+) sequestration.

@article{graus2018vppase, abstract = {The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H(+) -ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PP(i) hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na(+) sequestration.}, author = {Graus, D. and Konrad, K. R. and Bemm, F. and Patir Nebioglu, M. G. and Lorey, C. and Duscha, K. and Guthoff, T. and Herrmann, J. and Ferjani, A. and Cuin, T. A. and Roelfsema, M. R. G. and Schumacher, K. and Neuhaus, H. E. and Marten, I. and Hedrich, R.}, journal = {New Phytol}, keywords = {Death/drug}, note = {Graus, Dorothea Konrad, Kai R Bemm, Felix Patir Nebioglu, Meliha Gorkem Lorey, Christian Duscha, Kerstin Guthoff, Tilman Herrmann, Johannes Ferjani, Ali Cuin, Tracey Ann Roelfsema, M Rob G Schumacher, Karin Neuhaus, H Ekkehard Marten, Irene Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2018/06/26 New Phytol. 2018 Sep;219(4):1421-1432. doi: 10.1111/nph.15280. Epub 2018 Jun 25.}, number = 4, pages = {1421-1432}, title = {High V-PPase activity is beneficial under high salt loads, but detrimental without salinity}, type = {Journal Article}, volume = 219, year = 2018 }

%0 Journal Article %1 graus2018vppase %A Graus, D. %A Konrad, K. R. %A Bemm, F. %A Patir Nebioglu, M. G. %A Lorey, C. %A Duscha, K. %A Guthoff, T. %A Herrmann, J. %A Ferjani, A. %A Cuin, T. A. %A Roelfsema, M. R. G. %A Schumacher, K. %A Neuhaus, H. E. %A Marten, I. %A Hedrich, R. %D 2018 %J New Phytol %N 4 %P 1421-1432 %R 10.1111/nph.15280 %T High V-PPase activity is beneficial under high salt loads, but detrimental without salinity %U https://www.ncbi.nlm.nih.gov/pubmed/29938800 %V 219 %X The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H(+) -ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PP(i) hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na(+) sequestration.
TGF-beta family co-receptor function and signaling. Nickel, J.; Ten Dijke, P.; Mueller, T. D. In Acta Biochim Biophys Sin (Shanghai), 50(1), pp. 12–36. 2018.
- [ Abstract ]
- [ BibTeX ]
- [ EndNote ]
- [ URL ]
- [ DOI ]
Transforming growth factor-beta (TGF-beta) family members, which include TGF-betas, activins and bone morphogenetic proteins, are pleiotropic cytokines that elicit cell type-specific effects in a highly context-dependent manner in many different tissues. These secreted protein ligands signal via single-transmembrane Type I and Type II serine/threonine kinase receptors and intracellular SMAD transcription factors. Deregulation in signaling has been implicated in a broad array of diseases, and implicate the need for intricate fine tuning in cellular signaling responses. One important emerging mechanism by which TGF-beta family receptor signaling intensity, duration, specificity and diversity are regulated and/or mediated is through cell surface co-receptors. Here, we provide an overview of the co-receptors that have been identified for TGF-beta family members. While some appear to be specific to TGF-beta family members, others are shared with other pathways and provide possible ways for signal integration. This review focuses on novel functions of TGF-beta family co-receptors, which continue to be discovered.

@article{nickel2018tgfbeta, abstract = {Transforming growth factor-beta (TGF-beta) family members, which include TGF-betas, activins and bone morphogenetic proteins, are pleiotropic cytokines that elicit cell type-specific effects in a highly context-dependent manner in many different tissues. These secreted protein ligands signal via single-transmembrane Type I and Type II serine/threonine kinase receptors and intracellular SMAD transcription factors. Deregulation in signaling has been implicated in a broad array of diseases, and implicate the need for intricate fine tuning in cellular signaling responses. One important emerging mechanism by which TGF-beta family receptor signaling intensity, duration, specificity and diversity are regulated and/or mediated is through cell surface co-receptors. Here, we provide an overview of the co-receptors that have been identified for TGF-beta family members. While some appear to be specific to TGF-beta family members, others are shared with other pathways and provide possible ways for signal integration. This review focuses on novel functions of TGF-beta family co-receptors, which continue to be discovered.}, author = {Nickel, J. and Ten Dijke, P. and Mueller, T. D.}, journal = {Acta Biochim Biophys Sin (Shanghai)}, keywords = {uni_network}, note = {Nickel, Joachim Ten Dijke, Peter Mueller, Thomas D eng Review China 2018/01/03 Acta Biochim Biophys Sin (Shanghai). 2018 Jan 1;50(1):12-36. doi: 10.1093/abbs/gmx126.}, number = 1, pages = {12-36}, title = {TGF-beta family co-receptor function and signaling}, type = {Journal Article}, volume = 50, year = 2018 }

%0 Journal Article %1 nickel2018tgfbeta %A Nickel, J. %A Ten Dijke, P. %A Mueller, T. D. %D 2018 %J Acta Biochim Biophys Sin (Shanghai) %N 1 %P 12-36 %R 10.1093/abbs/gmx126 %T TGF-beta family co-receptor function and signaling %U https://www.ncbi.nlm.nih.gov/pubmed/29293886https://watermark.silverchair.com/gmx126.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAABH8wggR7BgkqhkiG9w0BBwagggRsMIIEaAIBADCCBGEGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMnTMrh0xVdPS4-mr7AgEQgIIEMnobTpVjLs6_Yu9Gh6feYO4yZ4PIPPtdn_KhB0Tjr0nd7jqoBZ3VwQjs-SQnvpnfCzkIne3_9F5nzanT5Qc2ihXsknbcld58S8U0-H2PzT5ZZhuTdV1-GTVeLkUvnJlgqLQt_0tWB4PVdwAvUJ8rL9t4EKW0jEqvjfZwLSIGOLwEl8Gprsxw_W1SR_vp50qF_fbo-A7zp0dc4uYE2l69xpq-qyqC0PzL1hCvoUd66vhb65EqkEOO2r4NjLyK6OriW2o438GdpK37MXVSpqQ5_DBuHkF3vcbL8DU8teAUBlsk5H2Vtx1mry--1UsmLeEgjw9BOuq-FAJM37oNgvA2dSE83muhq3hSF6JFmtlwOT5025Qn-cvqoxUiZJAvJFKVHPwaEflAr_03Vd_-EFOO29Y10UmfQPfyVDFkCttaHZTB74GVGEneZv-cxAvWymUqWfcwcoZkfQ-HAL-pDHnK5ivhQoJX_S6G7_PoHSwIMZcA_zVzfalayQJow75FzYYb9YsJ5rcsPq7ivNsUF72TgjN4BrWUGQGrqXD-rcRvFPMsO9cmkahTdZnJ_Dia5-BDx9uKlDLIbBRfK9-AZ4_oV4Uzw3VUtTLEjzrz3Ud8tNZKwkGOSO7gsfEVJvPL3egax4l0mHjBKclAUW1YtnOcOj4jxK2bNKBunyYMXHWBhApNr4MG3KAAgW_7zd2lGlBGmQTzQh5g8xJhfgzs4HaPIKHZS1tvW10LMzOFFiDsYfHrttYLg9uFJ6x5uI-ly9QlOJp6Uhq2QErnHqYoC5t7_aqD0vDwPfjpmZcWLAXUMx72DyWbuiDLl2mrHJNdlEqTP4iFSyKmF0pxNK72VfnxU_IIvfTmQ_L2xha6S6wkmONAl4LOJX-9lUvzCReXHs5J5WjR3ZlUVw79gcY6HWVB2ReJHQVZ09Vbk3r1rknD-e4R7q3Dvwtl8sME9vJoA5lle_765LSwO94J4gPFxi0RYLZlt45ppoHstvCtXC6Olg8zuC1xWmWlKPPnC_sfbC3mu_1i8RbfzErA3zbYiU3bmltBcFfFTmkUUj9RqtwQ9J7Z6i3Ns8vb-bsjj3RF1nAi9bIM4cPiqKrs1AW4FI64NcDbHLSyw38js47daRN6i8-d3RT7_QHz386GhHqaDgSlaAVxN8hTGvAEMcTI9DWUoIZEsEnlOxL9pfxbs7HAF1NcRrwpkNc37zv_443WDVmn3QJ2z5koPDKwx7QvhrRlDMdoju-64OQn_Jrw_rTqsiFSR_c2z7ZT1-jcRCoIUuoIAOqsbuCGgTnHnLFLtB4bMGE2XMEqTgy388xsH7tZz4jLRHu1dLtG7mtDyATpA-5Y47glw-MlmOfsLYqizhF28CewsNox4gVHmEq8zEIBrvPWFhk4h33V_MrhrD8lm8vzOnSgVkhJIMkaIT2pp8Wm2NqdXw %V 50 %X Transforming growth factor-beta (TGF-beta) family members, which include TGF-betas, activins and bone morphogenetic proteins, are pleiotropic cytokines that elicit cell type-specific effects in a highly context-dependent manner in many different tissues. These secreted protein ligands signal via single-transmembrane Type I and Type II serine/threonine kinase receptors and intracellular SMAD transcription factors. Deregulation in signaling has been implicated in a broad array of diseases, and implicate the need for intricate fine tuning in cellular signaling responses. One important emerging mechanism by which TGF-beta family receptor signaling intensity, duration, specificity and diversity are regulated and/or mediated is through cell surface co-receptors. Here, we provide an overview of the co-receptors that have been identified for TGF-beta family members. While some appear to be specific to TGF-beta family members, others are shared with other pathways and provide possible ways for signal integration. This review focuses on novel functions of TGF-beta family co-receptors, which continue to be discovered.

Schwerpunkt Pflanzenwissenschaften am Julius-von-Sachs-Institut

Einrichtungen

Molekulare Pflanzenphysiologie und Biophysik (Botanik I)

Ökophysiologie der Pflanzen (Botanik II)

Pharmazeutische Biologie

Botanischer Garten

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Veranstaltungskalender

Nachwuchs

Nachwuchsgruppen

Habilitand/innen

Alumni/Nachwuchs mit Professuren

Zukunftskonzept

Metabolomics Core Unit

Lehre

Aktuelle Meldungen aus dem Biozentrum

Ein schnelles Ende für mRNA

Wüstenameisen nutzen Polarität des Erdmagnetfeldes zur Orientierung

Ein Bauplan für die Innere Uhr des Gehirns

Wie Landwirtschaft ohne chemischen Pflanzenschutz geht

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