TY - JOUR A1 - Czarnocka, Weronika A1 - Van Der Kelen, Katrien A1 - Willems, Patrick A1 - Szechynska-Hebda, Magdalena A1 - Shahnejat-Bushehri, Sara A1 - Balazadeh, Salma A1 - Rusaczonek, Anna A1 - Müller-Röber, Bernd A1 - Van Breusegem, Frank A1 - Karpinski, Stanislaw T1 - The dual role of LESION SIMULATING DISEASE 1 as a condition-dependent scaffold protein and transcription regulator JF - Plant, cell & environment : cell physiology, whole-plant physiology, community physiology N2 - Since its discovery over two decades ago as an important cell death regulator in Arabidopsis thaliana, the role of LESION SIMULATING DISEASE 1 (LSD1) has been studied intensively within both biotic and abiotic stress responses as well as with respect to plant fitness regulation. However, its molecular mode of action remains enigmatic. Here, we demonstrate that nucleo-cytoplasmic LSD1 interacts with a broad range of other proteins that are engaged in various molecular pathways such as ubiquitination, methylation, cell cycle control, gametogenesis, embryo development and cell wall formation. The interaction of LSD1 with these partners is dependent on redox status, as oxidative stress significantly changes the quantity and types of LSD1-formed complexes. Furthermore, we show that LSD1 regulates the number and size of leaf mesophyll cells and affects plant vegetative growth. Importantly, we also reveal that in addition to its function as a scaffold protein, LSD1 acts as a transcriptional regulator. Taken together, our results demonstrate that LSD1 plays a dual role within the cell by acting as a condition-dependent scaffold protein and as a transcription regulator. KW - Arabidopsis KW - thaliana KW - dry weight KW - LSD1 KW - oxidative stress KW - protein interaction KW - transcription regulation Y1 - 2017 U6 - https://doi.org/10.1111/pce.12994 SN - 0140-7791 SN - 1365-3040 VL - 40 SP - 2644 EP - 2662 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Castellanos, Reynel Urrea A1 - Friedrich, Thomas A1 - Petrovic, Nevena A1 - Altmann, Simone A1 - Brzezinka, Krzysztof A1 - Gorka, Michal A1 - Graf, Alexander A1 - Bäurle, Isabel T1 - FORGETTER2 protein phosphatase and phospholipase D modulate heat stress memory in Arabidopsis JF - The plant journal N2 - Plants can mitigate environmental stress conditions through acclimation. In the case of fluctuating stress conditions such as high temperatures, maintaining a stress memory enables a more efficient response upon recurring stress. In a genetic screen forArabidopsis thalianamutants impaired in the memory of heat stress (HS) we have isolated theFORGETTER2(FGT2) gene, which encodes a type 2C protein phosphatase (PP2C) of the D-clade.Fgt2mutants acquire thermotolerance normally; however, they are defective in the memory of HS. FGT2 interacts with phospholipase D alpha 2 (PLD alpha 2), which is involved in the metabolism of membrane phospholipids and is also required for HS memory. In summary, we have uncovered a previously unknown component of HS memory and identified the FGT2 protein phosphatase and PLD alpha 2 as crucial players, suggesting that phosphatidic acid-dependent signaling or membrane composition dynamics underlie HS memory. KW - priming KW - protein phosphatase KW - stress memory KW - heat stress KW - Arabidopsis KW - thaliana Y1 - 2020 U6 - https://doi.org/10.1111/tpj.14927 SN - 0960-7412 SN - 1365-313X VL - 104 IS - 1 SP - 7 EP - 17 PB - Wiley CY - Hoboken ER - TY - GEN A1 - Breuninger, Holger A1 - Lenhard, Michael T1 - Expression of the central growth regulator BIG BROTHER is regulated by multiple cis-elements N2 - Background Much of the organismal variation we observe in nature is due to differences in organ size. The observation that even closely related species can show large, stably inherited differences in organ size indicates a strong genetic component to the control of organ size. Despite recent progress in identifying factors controlling organ growth in plants, our overall understanding of this process remains limited, partly because the individual factors have not yet been connected into larger regulatory pathways or networks. To begin addressing this aim, we have studied the upstream regulation of expression of BIG BROTHER (BB), a central growth-control gene in Arabidopsis thaliana that prevents overgrowth of organs. Final organ size and BB expression levels are tightly correlated, implying the need for precise control of its expression. BB expression mirrors proliferative activity, yet the gene functions to limit proliferation, suggesting that it acts in an incoherent feedforward loop downstream of growth activators to prevent over-proliferation. Results To investigate the upstream regulation of BB we combined a promoter deletion analysis with a phylogenetic footprinting approach. We were able to narrow down important, highly conserved, cis-regulatory elements within the BB promoter. Promoter sequences of other Brassicaceae species were able to partially complement the A. thaliana bb-1 mutant, suggesting that at least within the Brassicaceae family the regulatory pathways are conserved. Conclusions This work underlines the complexity involved in precise quantitative control of gene expression and lays the foundation for identifying important upstream regulators that determine BB expression levels and thus final organ size. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 374 KW - Asymmetric interlaced PCR KW - Organ Groth KW - DNA Elements KW - Arabidopsis KW - Plants KW - Brassicaceae KW - Phylogeny KW - Database KW - Place KW - Size Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-400971 ER - TY - THES A1 - Blacha, Anna Maria T1 - Investigating the role of regulatory genes in heterosis for superior growth and biomass production in Arabidopsis thaliana T1 - Die Rolle von Regulatorischen Genen bei der Entstehung von Wachstums- und Biomassen-Heterosis in Arabidopsis thaliana N2 - ‘Heterosis’ is a term used in genetics and breeding referring to hybrid vigour or the superiority of hybrids over their parents in terms of traits such as size, growth rate, biomass, fertility, yield, nutrient content, disease resistance or tolerance to abiotic and abiotic stress. Parental plants which are two different inbred (pure) lines that have desired traits are crossed to obtain hybrids. Maximum heterosis is observed in the first generation (F1) of crosses. Heterosis has been utilised in plant and animal breeding programs for at least 90 years: by the end of the 21st century, 65% of worldwide maize production was hybrid-based. Generally, it is believed that an understanding of the molecular basis of heterosis will allow the creation of new superior genotypes which could either be used directly as F1 hybrids or form the basis for the future breeding selection programmes. Two selected accessions of a research model plant Arabidopsis thaliana (thale cress) were crossed to obtain hybrids. These typically exhibited a 60-80% increase of biomass when compared to the average weight of both parents. This PhD project focused on investigating the role of selected regulatory genes given their potentially key involvement in heterosis. In the first part of the project, the most appropriate developmental stage for this heterosis study was determined by metabolite level measurements and growth observations in parents and hybrids. At the selected stage, around 60 candidate regulatory genes (i.e. differentially expressed in hybrids when compared to parents) were identified. Of these, the majority were transcription factors, genes that coordinate the expression of other genes. Subsequent expression analyses of the candidate genes in biomass-heterotic hybrids of other Arabidopsis accessions revealed a differential expression in a gene subset, highlighting their relevance for heterosis. Moreover, a fraction of the candidate regulatory genes were found within DNA regions closely linked to the genes that underlie the biomass or growth heterosis. Additional analyses to validate the role of selected candidate regulatory genes in heterosis appeared insufficient to establish their role in heterosis. This uncovered a need for using novel approaches as discussed in the thesis. Taken together, the work provided an insight into studies on the molecular mechanisms underlying heterosis. Although studies on heterosis date back to more than one hundred years, this project as many others revealed that more investigations will be needed to uncover this phenomenon. N2 - „Heterosis“ ist ein in der Genetik und der Züchtung verwendeter Begriff, der die Hybridwüchsigkeit oder die Überlegenheit der Hybriden über ihre Eltern in Bezug auf Eigenschaften wie Größe, Wachstumsrate, Biomasse, Fruchtbarkeit, Ertrag, Nährstoffgehalt, Widerstand gegen Krankheiten oder Toleranz in Bezug auf biotischen oder abiotischen Stress bezeichnet. Um Hybriden zu erzeugen, werden aus zwei verschiedenen Inzuchtlinien (reine Linien) bestehende Elternpflanzen, welche die gewünschten Eigenschaften besitzen, miteinander gekreuzt. Der stärkste Heterosiseffekt wird in der ersten Kreuzungsgeneration (F1) beobachtet. Heterosis wird in Pflanzen- und Tierzuchtprogrammen schon seit mindestens 90 Jahren genutzt. So beruhte zum Ende des 20. Jahrhunderts 65% der weltweiten Maisproduktion auf Hybridzüchtung. Es wird angenommen, dass ein Verständnis der molekularen Grundlagen der Heterosis die Schaffung neuer, überlegener Genotypen erlaubt, die dann direkt als F1-Hybriden verwendet, oder als Grundlage für zukünftige Zucht- und Selektionsprogramme dienen können. Zwei ausgewählte Akzessionen der Modellpflanze Arabidopsis thaliana (Ackerschmalwand) wurden miteinander gekreuzt, um Hybriden zu erzeugen. Verglichen mit dem durchschnittlichen Gewicht ihren beiden Elternlinien zeigten diese eine 60-80%ige Zunahme an Biomasse. Diese Doktorarbeit befasst sich damit, die Rolle ausgewählter, regulatorischer Gene und ihre mögliche Schlüsselrolle bei der Heterosis zu untersuchen. Im ersten Teil der Arbeit wurde anhand der Gehaltsbestimmung ausgewählter Stoffwechselprodukte und Wachstumsbeobachtungen bei den Eltern und Hybriden das günstigste Entwicklungsstadium für diese Heterosisstudie bestimmt. In diesem Entwicklungsstadium wurden ungefähr 60 regulatorische Gene (d.h. Expressionsunterschiede zwischen Hybriden und Elternlinien) als Kandidaten identifiziert. Ein Großteil dieser Kandidaten waren Transkriptionsfaktoren, also Gene, die die Expression anderer Gene regulieren. Die nachfolgende Expressionsanalyse dieser Kandidatengene in Biomasse-Heterosis Hybriden anderer Arabidopsis Akzessionen zeigte bei einem Teil dieser Gene Expressionsunterschiede, die ihre Bedeutung bei der Heterosis betonen. Darüber hinaus wurde ein Teil dieser regulatorischen Kandidatengene innerhalb von DNS-Regionen gefunden, die eng mit Biomasse- oder Wachstumsheterosis in Verbindung stehen, und somit ihre Wichtigkeit in Bezug auf Heterosis unterstreichen. Weitergehende Analysen um die Rolle dieser ausgewählten regulatorischen Kandidatengene bei der Heterosis aufzuklären, waren nicht aussagekräftig genug, um ihre Rolle bei der Heterosis zu bestätigen. In der Doktorarbeit wird die Notwendigkeit neue Wege zur Aufklärung der Heterosis zu finden, diskutiert. Zusammenfassend gibt diese Doktorarbeit einen Einblick über Studien der molekularen Mechanismen, die der Heterosis zugrunde liegen. Diese Arbeit zeigt, dass obwohl Heterosis bereits seit mehr als hundert Jahren studiert wird, weitere Untersuchungen zur Aufklärung dieses Phänomens notwendig sind. KW - Heterosis KW - Arabidopsis KW - Biomasse KW - Regulatorische Gene KW - heterosis KW - Arabidopsis KW - biomass KW - regulatory genes Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-46146 ER - TY - JOUR A1 - Benina, Maria A1 - Ribeiro, Dimas Mendes A1 - Gechev, Tsanko S. A1 - Müller-Röber, Bernd A1 - Schippers, Jos H. M. T1 - A cell type-specific view on the translation of mRNAs from ROS-responsive genes upon paraquat treatment of Arabidopsis thaliana leaves JF - Plant, cell & environment : cell physiology, whole-plant physiology, community physiology N2 - Oxidative stress causes dramatic changes in the expression levels of many genes. The formation of a functional protein through successful mRNA translation is central to a coordinated cellular response. To what extent the response towards reactive oxygen species (ROS) is regulated at the translational level is poorly understood. Here we analysed leaf- and tissue-specific translatomes using a set of transgenic Arabidopsis thaliana lines expressing a FLAG-tagged ribosomal protein to immunopurify polysome-bound mRNAs before and after oxidative stress. We determined transcript levels of 171 ROS-responsive genes upon paraquat treatment, which causes formation of superoxide radicals, at the whole-organ level. Furthermore, the translation of mRNAs was determined for five cell types: mesophyll, bundle sheath, phloem companion, epidermal and guard cells. Mesophyll and bundle sheath cells showed the strongest response to paraquat treatment. Interestingly, several ROS-responsive transcription factors displayed cell type-specific translation patterns, while others were translated in all cell types. In part, cell type-specific translation could be explained by the length of the 5-untranslated region (5-UTR) and the presence of upstream open reading frames (uORFs). Our analysis reveals insights into the translational regulation of ROS-responsive genes, which is important to understanding cell-specific responses and functions during oxidative stress. The study illustrates the response of different Arabidopsis thaliana leaf cells and tissues to oxidative stress at the translational level, an aspect of reactive oxygen species (ROS) biology that has been little studied in the past. Our data reveal insights into how translational regulation of ROS-responsive genes is fine-tuned at the cellular level, a phenomenon contributing to the integrated physiological response of leaves to stresses involving changes in ROS levels. KW - Arabidopsis KW - gene regulation KW - oxidative stress KW - tissue-specific KW - translation Y1 - 2015 U6 - https://doi.org/10.1111/pce.12355 SN - 0140-7791 SN - 1365-3040 VL - 38 IS - 2 SP - 349 EP - 363 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Balazadeh, Salma A1 - Schildhauer, Joerg A1 - Araujo, Wagner L. A1 - Munne-Bosch, Sergi A1 - Fernie, Alisdair R. A1 - Proost, Sebastian A1 - Humbeck, Klaus A1 - Müller-Röber, Bernd T1 - Reversal of senescence by N resupply to N-starved Arabidopsis thaliana: transcriptomic and metabolomic consequences JF - Journal of experimental botany N2 - Leaf senescence is a developmentally controlled process, which is additionally modulated by a number of adverse environmental conditions. Nitrogen shortage is a well-known trigger of precocious senescence in many plant species including crops, generally limiting biomass and seed yield. However, leaf senescence induced by nitrogen starvation may be reversed when nitrogen is resupplied at the onset of senescence. Here, the transcriptomic, hormonal, and global metabolic rearrangements occurring during nitrogen resupply-induced reversal of senescence in Arabidopsis thaliana were analysed. The changes induced by senescence were essentially in keeping with those previously described; however, these could, by and large, be reversed. The data thus indicate that plants undergoing senescence retain the capacity to sense and respond to the availability of nitrogen nutrition. The combined data are discussed in the context of the reversibility of the senescence programme and the evolutionary benefit afforded thereby. Future prospects for understanding and manipulating this process in both Arabidopsis and crop plants are postulated. KW - Arabidopsis KW - gene expression KW - metabolomics KW - nitrogen limitation KW - senescence KW - transcriptome Y1 - 2014 U6 - https://doi.org/10.1093/jxb/eru119 SN - 0022-0957 SN - 1460-2431 VL - 65 IS - 14 SP - 3975 EP - 3992 PB - Oxford Univ. Press CY - Oxford ER - TY - THES A1 - Arvidsson, Samuel Janne T1 - Identification of growth-related tonoplast proteins in Arabidopsis thaliana T1 - Identifizierung von wachstumsrelevanten Tonoplast-Proteinen in Arabidopsis thaliana (Ackerschmalwand) N2 - In a very simplified view, the plant leaf growth can be reduced to two processes, cell division and cell expansion, accompanied by expansion of their surrounding cell walls. The vacuole, as being the largest compartment of the plant cell, plays a major role in controlling the water balance of the plant. This is achieved by regulating the osmotic pressure, through import and export of solutes over the vacuolar membrane (the tonoplast) and by controlling the water channels, the aquaporins. Together with the control of cell wall relaxation, vacuolar osmotic pressure regulation is thought to play an important role in cell expansion, directly by providing cell volume and indirectly by providing ion and pH homestasis for the cytosoplasm. In this thesis the role of tonoplast protein coding genes in cell expansion in the model plant Arabidopsis thaliana is studied and genes which play a putative role in growth are identified. Since there is, to date, no clearly identified protein localization signal for the tonoplast, there is no possibility to perform genome-wide prediction of proteins localized to this compartment. Thus, a series of recent proteomic studies of the tonoplast were used to compile a list of cross-membrane tonoplast protein coding genes (117 genes), and other growth-related genes from notably the growth regulating factor (GRF) and expansin families were included (26 genes). For these genes a platform for high-throughput reverse transcription quantitative real time polymerase chain reaction (RT-qPCR) was developed by selecting specific primer pairs. To this end, a software tool (called QuantPrime, see http://www.quantprime.de) was developed that automatically designs such primers and tests their specificity in silico against whole transcriptomes and genomes, to avoid cross-hybridizations causing unspecific amplification. The RT-qPCR platform was used in an expression study in order to identify candidate growth related genes. Here, a growth-associative spatio-temporal leaf sampling strategy was used, targeting growing regions at high expansion developmental stages and comparing them to samples taken from non-expanding regions or stages of low expansion. Candidate growth related genes were identified after applying a template-based scoring analysis on the expression data, ranking the genes according to their association with leaf expansion. To analyze the functional involvement of these genes in leaf growth on a macroscopic scale, knockout mutants of the candidate growth related genes were screened for growth phenotypes. To this end, a system for non-invasive automated leaf growth phenotyping was established, based on a commercially available image capture and analysis system. A software package was developed for detailed developmental stage annotation of the images captured with the system, and an analysis pipeline was constructed for automated data pre-processing and statistical testing, including modeling and graph generation, for various growth-related phenotypes. Using this system, 24 knockout mutant lines were analyzed, and significant growth phenotypes were found for five different genes. N2 - Sehr vereinfacht gesagt kann Blattwachstum auf zwei Prozesse reduziert werden, Zellteilung und Zellexpansion, gefolgt von Zellwandexpansion. Die Vakuole, das größte Organell der Zelle, übt durch die Kontrolle des Wasserhaushaltes der Pflanze eine wichtige Funktion im Zusammenhang mit der Zellexpansion aus. Dies geschieht durch die Regulierung des osmotischen Druckes, durch Import und Export von organischen und anorganischen Ionen über die Vakuolenmembran (den Tonoplast) und durch die Kontrolle ihrer Wasserkanäle (der Aquaporine). Es wird angenommen, dass die Regulierung des vakuolären osmotischen Druckes eine große Rolle bei der Zellexpansion spielt, da der osmotische Druck die Stärke der mechanischen Kraft des Tonoplast auf die Plasmamembran und die Zellwand bestimmt. In dieser Dissertation wird die Rolle von Tonoplastproteinen und ihrer Gene auf die Zellexpansion anhand der Modellpflanze Arabidopsis thaliana (Ackerschmalwand) untersucht, und Kandidaten für wachstumsrelevante Gene werden identifiziert. Da bisher noch kein Signal für die Lokalisierung von Proteinen im Tonoplast identifiziert wurde, gibt es keine Möglichkeit, genomweite Voraussagen über solche Proteinlokalisierungen zu machen. Daher haben wir eine Reihe von aktuellen Proteom-Studien genutzt, um eine Liste von 117 Genen, die für transmembrane tonoplastproteinkodierende Gene kodieren, zusammenzustellen. Zusätzlich wurden andere wachstumsrelevante Gene und Zellzyklus-Gene in die Liste aufgenommen (38 Gene). Die Expression der Gene während der Blattentwicklung sollte mittels einer sensitiven Technik, der quantitativen Polymerasekettenreaktion (qPCR), untersucht werden. Um rasch die für dieses Verfahren notwendigen Oligonukleotide zu entwerfen, wurde ein Computerprogramm („QuantPrime“) entwickelt. Das Programm entwirft automatisch solche Oligonukleotide und überprüft deren Spezifizität in silico auf Ebene der Transkriptome und Genome um Kreuz-Hybridisierungen zu vermeiden, die zu unspezifischen Amplifikationen führen würden. Die qPCR-Plattform wurde in einer Expressions-Studie eingesetzt, um wachstumsrelevante Gen-Kandidaten zu identifizieren. Um wachstumsaktive und nichtaktive Prozesse vergleichen zu können, wurden Proben von unterschiedlichen Bereichen des Blattes zu unterschiedlichen Wachstumsstadien beprobt. Eine musterbasierte Expressionsdatenanalyse wurde eingesetzt, um die Gene hinischtlich ihrer Assoziation mit der Blattexpansionen in eine Rangordnung zu bringen. Die Gene mit dem höchsten Rang wurden als Kandidaten für weitere Experimente ausgewählt. Um die funktionelle Beteiligung dieser Gene auf einer makroskopischen Ebene zu untersuchen, wurden Knockout-Mutanten für die Gen-Kandidaten hinsichtlich ihres Wachstums analysiert. Zu diesem Zweck wurde ein System für die automatisierte Phänotypisierung des Blattwachstums etabliert. Zum einen wurde ein Programm-Paket für detaillierte Annotation von Wachstumsstadien und zum anderen ein Analyse-Paket für automatisierte Datenvorbereitung und statistische Tests entwickelt. Das Analyse-Paket erlaubt die Modellierung und graphische Darstellung verschiedener wachstumsrelevanter Phänotypen. Mit Hilfe dieses Systems wurden 24 Knockout-Mutanten untersucht und signifikante Phänotypen wurden für fünf verschiedene Gene gefunden. KW - Ackerschmalwand KW - Wachstum KW - Tonoplast KW - qPCR KW - Phänotypisierung KW - Arabidopsis KW - Growth KW - Tonoplast KW - qPCR KW - Phenotyping Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-52408 ER - TY - JOUR A1 - Allu, Annapurna Devi A1 - Soja, Aleksandra Maria A1 - Wu, Anhui A1 - Szymanski, Jedrzej A1 - Balazadeh, Salma T1 - Salt stress and senescence: identification of cross-talk regulatory components JF - Journal of experimental botany N2 - Leaf senescence is an active process with a pivotal impact on plant productivity. It results from extensive signalling cross-talk coordinating environmental factors with intrinsic age-related mechanisms. Although many studies have shown that leaf senescence is affected by a range of external parameters, knowledge about the regulatory systems that govern the interplay between developmental programmes and environmental stress is still vague. Salinity is one of the most important environmental stresses that promote leaf senescence and thus affect crop yield. Improving salt tolerance by avoiding or delaying senescence under stress will therefore play an important role in maintaining high agricultural productivity. Experimental evidence suggests that hydrogen peroxide (H2O2) functions as a common signalling molecule in both developmental and salt-induced leaf senescence. In this study, microarray-based gene expression profiling on Arabidopsis thaliana plants subjected to long-term salinity stress to induce leaf senescence was performed, together with co-expression network analysis for H2O2-responsive genes that are mutually up-regulated by salt induced-and developmental leaf senescence. Promoter analysis of tightly co-expressed genes led to the identification of seven cis-regulatory motifs, three of which were known previously, namely CACGTGT and AAGTCAA, which are associated with reactive oxygen species (ROS)-responsive genes, and CCGCGT, described as a stress-responsive regulatory motif, while the others, namely ACGCGGT, AGCMGNC, GMCACGT, and TCSTYGACG were not characterized previously. These motifs are proposed to be novel elements involved in the H2O2-mediated control of gene expression during salinity stress-triggered and developmental senescence, acting through upstream transcription factors that bind to these sites. KW - Arabidopsis KW - hydrogen peroxide KW - longevity KW - reactive oxygen species KW - salt stress KW - senescence KW - signal cross-talk KW - transcription factor Y1 - 2014 U6 - https://doi.org/10.1093/jxb/eru173 SN - 0022-0957 SN - 1460-2431 VL - 65 IS - 14 SP - 3993 EP - 4008 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Allu, Annapurna Devi A1 - Brotman, Yariv A1 - Xue, Gang-Ping A1 - Balazadeh, Salma T1 - Transcription factor ANAC032 modulates JA/SA signalling in response to Pseudomonas syringae infection JF - EMBO reports N2 - Responses to pathogens, including host transcriptional reprogramming, require partially antagonistic signalling pathways dependent on the phytohormones salicylic (SA) and jasmonic (JA) acids. However, upstream factors modulating the interplay of these pathways are not well characterized. Here, we identify the transcription factor ANAC032 from Arabidopsis thaliana as one such regulator in response to the bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst). ANAC032 directly represses MYC2 activation upon Pst attack, resulting in blockage of coronatine-mediated stomatal reopening which restricts entry of bacteria into plant tissue. Furthermore, ANAC032 activates SA signalling by repressing NIMIN1, a key negative regulator of SA-dependent defence. Finally, ANAC032 reduces expression of JA-responsive genes, including PDF1.2A. Thus, ANAC032 enhances resistance to Pst by generating an orchestrated transcriptional output towards key SA- and JA-signalling genes coordinated through direct binding of ANAC032 to the MYC2, NIMIN1 and PDF1.2A promoters. KW - Arabidopsis KW - jasmonic acid KW - pathogens KW - salicylic acid KW - transcription factor Y1 - 2016 U6 - https://doi.org/10.15252/embr.201642197 SN - 1469-221X SN - 1469-3178 VL - 17 SP - 1578 EP - 1589 PB - Wiley-Blackwell CY - Hoboken ER -