Janz, Dennis

[["dc.bibliographiccitation.firstpage","129"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","New Phytologist"],["dc.bibliographiccitation.lastpage","141"],["dc.bibliographiccitation.volume","194"],["dc.contributor.author","Janz, Dennis"],["dc.contributor.author","Lautner, Silke"],["dc.contributor.author","Wildhagen, Henning"],["dc.contributor.author","Behnke, Katja"],["dc.contributor.author","Schnitzler, Jörg-Peter"],["dc.contributor.author","Rennenberg, Heinz"],["dc.contributor.author","Fromm, Jörg"],["dc.contributor.author","Polle, Andrea"],["dc.date.accessioned","2017-09-07T11:49:19Z"],["dc.date.available","2017-09-07T11:49:19Z"],["dc.date.issued","2012"],["dc.description.abstract","Summary - Salinity causes osmotic stress and limits biomass production of plants. The goal of this study was to investigate mechanisms underlying hydraulic adaptation to salinity. - Anatomical, ecophysiological and transcriptional responses to salinity were investigated in the xylem of a salt‐sensitive (Populus × canescens) and a salt‐tolerant species (Populus euphratica). - Moderate salt stress, which suppressed but did not abolish photosynthesis and radial growth in P. × canescens, resulted in hydraulic adaptation by increased vessel frequencies and decreased vessel lumina. Transcript abundances of a suite of genes (FLA, COB‐like, BAM, XET, etc.) previously shown to be activated during tension wood formation, were collectively suppressed in developing xylem, whereas those for stress and defense‐related genes increased. A subset of cell wall‐related genes was also suppressed in salt‐exposed P. euphratica, although this species largely excluded sodium and showed no anatomical alterations. Salt exposure influenced cell wall composition involving increases in the lignin : carbohydrate ratio in both species. - In conclusion, hydraulic stress adaptation involves cell wall modifications reciprocal to tension wood formation that result in the formation of a novel type of reaction wood in upright stems named ‘pressure wood’. Our data suggest that transcriptional co‐regulation of a core set of genes determines reaction wood composition."],["dc.identifier.doi","10.1111/j.1469-8137.2011.03975.x"],["dc.identifier.gro","3147274"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7404"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/4894"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","chake"],["dc.relation.issn","0028-646X"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","Salt stress induces the formation of a novel type of ‘pressure wood’ in two Populus species"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dc.type.version","submitted_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","150"],["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.journal","BMC Plant Biology"],["dc.bibliographiccitation.lastpage","17"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Janz, Dennis"],["dc.contributor.author","Behnke, Katja"],["dc.contributor.author","Schnitzler, Jörg-Peter"],["dc.contributor.author","Kanawati, Basem"],["dc.contributor.author","Schmitt-Kopplin, Philippe"],["dc.contributor.author","Polle, Andrea"],["dc.date.accessioned","2017-09-07T11:50:39Z"],["dc.date.available","2017-09-07T11:50:39Z"],["dc.date.issued","2010"],["dc.description.abstract","Background Populus euphratica is a salt tolerant and Populus × canescens a salt sensitive poplar species. Because of low transcriptional responsiveness of P. euphratica to salinity we hypothesized that this species exhibits an innate activation of stress protective genes compared with salt sensitive poplars. To test this hypothesis, the transcriptome and metabolome of mature unstressed leaves of P. euphratica and P. × canescens were compared by whole genome microarray analyses and FT-ICR-MS metabolite profiling. Results Direct cross-species comparison of the transcriptomes of the two poplar species from phylogenetically different sections required filtering of the data set. Genes assigned to the GO slim categories 'mitochondria', 'cell wall', 'transport', 'energy metabolism' and 'secondary metabolism' were significantly enriched, whereas genes in the categories 'nucleus', 'RNA or DNA binding', 'kinase activity' and 'transcription factor activity' were significantly depleted in P. euphratica compared with P. × canescens. Evidence for a general activation of stress relevant genes in P. euphratica was not detected. Pathway analyses of metabolome and transcriptome data indicated stronger accumulation of primary sugars, activation of pathways for sugar alcohol production, and faster consumption of secondary metabolites in P. euphratica compared to P. × canescens. Physiological measurements showing higher respiration, higher tannin and soluble phenolic contents as well as enrichment of glucose and fructose in P. euphratica compared to P. × canescens corroborated the results of pathway analyses. Conclusion P. euphratica does not rely on general over-expression of stress pathways to tolerate salt stress. Instead, it exhibits permanent activation of control mechanisms for osmotic adjustment (sugar and sugar alcohols), ion compartmentalization (sodium, potassium and other metabolite transporters) and detoxification of reactive oxygen species (phenolic compounds). The evolutionary adaptation of P. euphratica to saline environments is apparently linked with higher energy requirement of cellular metabolism and a loss of transcriptional regulation."],["dc.identifier.doi","10.1186/1471-2229-10-150"],["dc.identifier.gro","3147722"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/5667"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5120"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.notes.submitter","chake"],["dc.relation.issn","1471-2229"],["dc.rights","CC BY 2.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.0"],["dc.title","Pathway analysis of the transcriptome and metabolome of salt sensitive and tolerant poplar species reveals evolutionary adaption of stress tolerance mechanisms"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","61"],["dc.bibliographiccitation.issue","1-2"],["dc.bibliographiccitation.journal","Plant molecular biology"],["dc.bibliographiccitation.lastpage","75"],["dc.bibliographiccitation.volume","74"],["dc.contributor.author","Behnke, Katja"],["dc.contributor.author","Kaiser, Andreas"],["dc.contributor.author","Zimmer, Ina"],["dc.contributor.author","Brüggemann, Nicolas"],["dc.contributor.author","Janz, Dennis"],["dc.contributor.author","Polle, Andrea"],["dc.contributor.author","Hampp, Rüdiger"],["dc.contributor.author","Hänsch, Robert"],["dc.contributor.author","Popko, Jennifer"],["dc.contributor.author","Schmitt-Kopplin, Philippe"],["dc.contributor.author","Ehlting, Barbara"],["dc.contributor.author","Rennenberg, Heinz"],["dc.contributor.author","Barta, Csengele"],["dc.contributor.author","Loreto, Francesco"],["dc.contributor.author","Schnitzler, Jörg-Peter"],["dc.date.accessioned","2018-06-12T08:31:25Z"],["dc.date.available","2018-06-12T08:31:25Z"],["dc.date.issued","2010"],["dc.description.abstract","In plants, isoprene plays a dual role: (a) as thermo-protective agent proposed to prevent degradation of enzymes/membrane structures involved in photosynthesis, and (b) as reactive molecule reducing abiotic oxidative stress. The present work addresses the question whether suppression of isoprene emission interferes with genome wide transcription rates and metabolite fluxes in grey poplar (Populus x canescens) throughout the growing season. Gene expression and metabolite profiles of isoprene emitting wild type plants and RNAi-mediated non-isoprene emitting poplars were compared by using poplar Affymetrix microarrays and non-targeted FT-ICR-MS (Fourier transform ion cyclotron resonance mass spectrometry). We observed a transcriptional down-regulation of genes encoding enzymes of phenylpropanoid regulatory and biosynthetic pathways, as well as distinct metabolic down-regulation of condensed tannins and anthocyanins, in non-isoprene emitting genotypes during July, when high temperature and light intensities possibly caused transient drought stress, as indicated by stomatal closure. Under these conditions leaves of non-isoprene emitting plants accumulated hydrogen peroxide (H(2)O(2)), a signaling molecule in stress response and negative regulator of anthocyanin biosynthesis. The absence of isoprene emission under high temperature and light stress resulted transiently in a new chemo(pheno)type with suppressed production of phenolic compounds. This may compromise inducible defenses and may render non-isoprene emitting poplars more susceptible to environmental stress."],["dc.identifier.doi","10.1007/s11103-010-9654-z"],["dc.identifier.pmid","20526857"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/6811"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/15024"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.eissn","1573-5028"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.title","RNAi-mediated suppression of isoprene emission in poplar transiently impacts phenolic metabolism under high temperature and high light intensities: a transcriptomic and metabolomic analysis"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]