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Nair A, Goyal I, Voß E, Mrozek P, Prajapati S, Thurow C, Tietze L, Tittmann K, Gatz C. N-hydroxypipecolic acid-induced transcription requires the salicylic acid signaling pathway at basal SA levels. Plant Physiol 2021; 187:2803-2819. [PMID: 34890459 PMCID: PMC8644824 DOI: 10.1093/plphys/kiab433] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 08/31/2021] [Indexed: 05/04/2023]
Abstract
Systemic acquired resistance (SAR) is a plant immune response established in uninfected leaves after colonization of local leaves with biotrophic or hemibiotrophic pathogens. The amino acid-derived metabolite N-hydroxypipecolic acid (NHP) travels from infected to systemic leaves, where it activates salicylic acid (SA) biosynthesis through the isochorismate pathway. The resulting increased SA levels are essential for induction of a large set of SAR marker genes and full SAR establishment. In this study, we show that pharmacological treatment of Arabidopsis thaliana with NHP induces a subset of SAR-related genes even in the SA induction-deficient2 (sid2/isochorismate synthase1) mutant, which is devoid of NHP-induced SA. NHP-mediated induction is abolished in sid2-1 NahG plants, in which basal SA levels are degraded. The SA receptor NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1) and its interacting TGACG SEQUENCE-SPECIFIC BINDING PROTEIN (TGA) transcription factors are required for the NHP-mediated induction of SAR genes at resting SA levels. Isothermal titration analysis determined a KD of 7.9 ± 0.5 µM for the SA/NPR1 complex, suggesting that basal levels of SA would not bind to NPR1 unless yet unknown potentially NHP-induced processes increase the affinity. Moreover, the nucleocytoplasmic protein PHYTOALEXIN DEFICIENT4 is required for a slight NHP-mediated increase in NPR1 protein levels and NHP-induced expression of SAR-related genes. Our experiments have unraveled that NHP requires basal SA and components of the SA signaling pathway to induce SAR genes. Still, the mechanism of NHP perception remains enigmatic.
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Affiliation(s)
- Aswin Nair
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Isha Goyal
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Edgar Voß
- Institute of Organic and Biomolecular Chemistry, Georg-August University Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Pascal Mrozek
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Sabin Prajapati
- Department of Molecular Enzymology, Göttingen Centre for Molecular Biosciences and Albrecht-von-Haller Institute, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
- Department of Structural Dynamics, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077 Göttingen, Germany
| | - Corinna Thurow
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Lutz Tietze
- Institute of Organic and Biomolecular Chemistry, Georg-August University Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Kai Tittmann
- Department of Molecular Enzymology, Göttingen Centre for Molecular Biosciences and Albrecht-von-Haller Institute, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
- Department of Structural Dynamics, Max-Planck-Institute for Biophysical Chemistry, Am Faßberg 11, 37077 Göttingen, Germany
| | - Christiane Gatz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
- Author for communication:
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Ulrich L, Schmitz J, Thurow C, Gatz C. The jasmonoyl-isoleucine receptor CORONATINE INSENSITIVE1 suppresses defense gene expression in Arabidopsis roots independently of its ligand. Plant J 2021; 107:1119-1130. [PMID: 34145662 DOI: 10.1111/tpj.15372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 06/02/2021] [Indexed: 06/12/2023]
Abstract
The F-box protein CORONANTINE INSENSITIVE1 (COI1) serves as the receptor for the plant hormone jasmonoyl-isoleucine (JA-Ile). COI1, its co-receptors of the JASMONATE ZIM-domain (JAZ) protein family, and JA-Ile form a functional unit that regulates growth or defense mechanisms in response to various stress cues. Strikingly, COI1, but not JA-Ile, is required for susceptibility of Arabidopsis thaliana towards the soil-borne vascular pathogen Verticillium longisporum. In order to obtain marker genes for further analysis of this JA-Ile-independent COI1 function, transcriptome analysis of roots of coi1 and allene oxide synthase (aos) plants (impaired in JA biosynthesis) was performed. Intriguingly, nearly all of the genes that are differentially expressed in coi1 versus aos and wild type are constitutively more highly expressed in coi1. To support our notion that COI1 acts independently of its known downstream signaling components, coi1 plants were complemented with a COI1 variant (COI1AA ) that is compromised in its interaction with JAZs. As expected, these plants showed only weak induction of the expression of the JA-Ile marker gene VEGETATIVE STORAGE PROTEIN2 after wounding and remained sterile. On the other hand, genes affected by COI1 but not by JA-Ile were still strongly repressed by COI1AA . We suggest that COI1 has a potential moonlighting function that serves to repress gene expression in a JA-Ile- and JAZ-independent manner.
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Affiliation(s)
- Louisa Ulrich
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - Johanna Schmitz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - Corinna Thurow
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
| | - Christiane Gatz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen, Göttingen, Germany
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Yildiz I, Mantz M, Hartmann M, Zeier T, Kessel J, Thurow C, Gatz C, Petzsch P, Köhrer K, Zeier J. The mobile SAR signal N-hydroxypipecolic acid induces NPR1-dependent transcriptional reprogramming and immune priming. Plant Physiol 2021; 186:1679-1705. [PMID: 33871649 PMCID: PMC8260123 DOI: 10.1093/plphys/kiab166] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/29/2021] [Indexed: 05/07/2023]
Abstract
N-hydroxypipecolic acid (NHP) accumulates in the plant foliage in response to a localized microbial attack and induces systemic acquired resistance (SAR) in distant leaf tissue. Previous studies indicated that pathogen inoculation of Arabidopsis (Arabidopsis thaliana) systemically activates SAR-related transcriptional reprogramming and a primed immune status in strict dependence of FLAVIN-DEPENDENT MONOOXYGENASE 1 (FMO1), which mediates the endogenous biosynthesis of NHP. Here, we show that elevations of NHP by exogenous treatment are sufficient to induce a SAR-reminiscent transcriptional response that mobilizes key components of immune surveillance and signal transduction. Exogenous NHP primes Arabidopsis wild-type and NHP-deficient fmo1 plants for a boosted induction of pathogen-triggered defenses, such as the biosynthesis of the stress hormone salicylic acid (SA), accumulation of the phytoalexin camalexin and branched-chain amino acids, as well as expression of defense-related genes. NHP also sensitizes the foliage systemically for enhanced SA-inducible gene expression. NHP-triggered SAR, transcriptional reprogramming, and defense priming are fortified by SA accumulation, and require the function of the transcriptional coregulator NON-EXPRESSOR OF PR GENES1 (NPR1). Our results suggest that NPR1 transduces NHP-activated immune signaling modes with predominantly SA-dependent and minor SA-independent features. They further support the notion that NHP functions as a mobile immune regulator capable of moving independently of active SA signaling between leaves to systemically activate immune responses.
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Affiliation(s)
- Ipek Yildiz
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Melissa Mantz
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Michael Hartmann
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Tatyana Zeier
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Jana Kessel
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Corinna Thurow
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, University of Göttingen, Göttingen D-37077, Germany
| | - Christiane Gatz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, University of Göttingen, Göttingen D-37077, Germany
| | - Patrick Petzsch
- Medical Faculty, Biological and Medical Research Center (BMFZ), Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Karl Köhrer
- Medical Faculty, Biological and Medical Research Center (BMFZ), Heinrich Heine University, Düsseldorf D-40225, Germany
| | - Jürgen Zeier
- Department of Biology, Institute for Molecular Ecophysiology of Plants, Heinrich Heine University, Düsseldorf D-40225, Germany
- Cluster of Excellence on Plant Sciences (CEPLAS), Düsseldorf D-40225, Germany
- Author for communication:
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Thurow C, Krischke M, Mueller MJ, Gatz C. Induction of Jasmonoyl-Isoleucine (JA-Ile)-Dependent JASMONATE ZIM-DOMAIN (JAZ) Genes in NaCl-Treated Arabidopsis thaliana Roots Can Occur at Very Low JA-Ile Levels and in the Absence of the JA/JA-Ile Transporter JAT1/AtABCG16. Plants 2020; 9:plants9121635. [PMID: 33255380 PMCID: PMC7760663 DOI: 10.3390/plants9121635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 12/03/2022]
Abstract
The plant hormone jasmonoyl-isoleucine (JA-Ile) is an important regulator of plant growth and defense in response to various biotic and abiotic stress cues. Under our experimental conditions, JA-Ile levels increased approximately seven-fold in NaCl-treated Arabidopsis thaliana roots. Although these levels were around 1000-fold lower than in wounded leaves, genes of the JA-Ile signaling pathway were induced by a factor of 100 or more. Induction was severely compromised in plants lacking the JA-Ile receptor CORONATINE INSENSITIVE 1 or enzymes required for JA-Ile biosynthesis. To explain efficient gene expression at very low JA-Ile levels, we hypothesized that salt-induced expression of the JA/JA-Ile transporter JAT1/AtABCG16 would lead to increased nuclear levels of JA-Ile. However, mutant plants with different jat1 alleles were similar to wild-type ones with respect to salt-induced gene expression. The mechanism that allows COI1-dependent gene expression at very low JA-Ile levels remains to be elucidated.
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Affiliation(s)
- Corinna Thurow
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, University of Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany;
| | - Markus Krischke
- Pharmaceutical Biology, Julius-von-Sachs-Institute for Biosciences, University of Würzburg, 97082 Würzburg, Germany; (M.K.); (M.J.M.)
| | - Martin J. Mueller
- Pharmaceutical Biology, Julius-von-Sachs-Institute for Biosciences, University of Würzburg, 97082 Würzburg, Germany; (M.K.); (M.J.M.)
| | - Christiane Gatz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller Institute for Plant Sciences, University of Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany;
- Correspondence:
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Li N, Uhrig JF, Thurow C, Huang LJ, Gatz C. Reconstitution of the Jasmonate Signaling Pathway in Plant Protoplasts. Cells 2019; 8:cells8121532. [PMID: 31795159 PMCID: PMC6953042 DOI: 10.3390/cells8121532] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 11/23/2019] [Accepted: 11/26/2019] [Indexed: 01/11/2023] Open
Abstract
The phytohormone jasmonic acid (JA) plays an important role in various plant developmental processes and environmental adaptations. The JA signaling pathway has been well-elucidated in the reference plant Arabidopsis thaliana. It starts with the perception of the active JA derivative, jasmonoyl-isoleucine (JA-Ile), by the F-box protein COI1 which is part of the E3-ligase SCFCOI1. Binding of JA-Ile enables the interaction between COI1 and JAZ repressor proteins. Subsequent degradation of JAZ proteins leads to the activation of transcription factors like e.g., MYC2. Here we demonstrate that the pathway can be reconstituted in transiently transformed protoplasts. Analysis of the stability of a JAZ1-fLuc fusion protein as a function of COI1 transiently expressed in coi1 protoplasts allows structure function analysis of both JAZs and COI1. Using this system, we found that conserved cysteines in COI1 influence steady state COI1 protein levels. Using a luciferase reporter gene under the control of the JAZ1 promoter enable to address those features of JAZ1 that are required for MYC2 repression. Interestingly, the conserved TIFY-motif previously described to interact with NINJA to recruit the corepressor TOPLESS is not necessary for repression. This result is in favor of the alternative repression mode that proposes a direct competition between repressive JAZs and promotive MEDIATOR25 at MYC2. Finally, using protoplasts from the aos coi1 double mutant, which is deficient in JA synthesis and perception, we provide a system that has the potential to study the activity of different COI1 variants in the presence of different ligands.
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Affiliation(s)
- Ning Li
- State Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees, Ministry of Education, Central South University of Forestry and Technology, Hunan 410004, China;
- College of Forestry, Central South University of Forestry and Technology, Hunan 410004, China
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, 37077 Göttingen, Germany; (J.F.U.); (C.T.)
| | - Joachim F. Uhrig
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, 37077 Göttingen, Germany; (J.F.U.); (C.T.)
| | - Corinna Thurow
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, 37077 Göttingen, Germany; (J.F.U.); (C.T.)
| | - Li-Jun Huang
- College of Forestry, Central South University of Forestry and Technology, Hunan 410004, China
- Correspondence: (L.-J.H.); (C.G.)
| | - Christiane Gatz
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, 37077 Göttingen, Germany; (J.F.U.); (C.T.)
- Correspondence: (L.-J.H.); (C.G.)
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Li N, Muthreich M, Huang LJ, Thurow C, Sun T, Zhang Y, Gatz C. TGACG-BINDING FACTORs (TGAs) and TGA-interacting CC-type glutaredoxins modulate hyponastic growth in Arabidopsis thaliana. New Phytol 2019; 221:1906-1918. [PMID: 30252136 DOI: 10.1111/nph.15496] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 09/13/2018] [Indexed: 06/08/2023]
Abstract
TGACG-BINDING FACTORs (TGAs) control the developmental or defense-related processes. In Arabidopsis thaliana, the functions of at least TGA2 and PERIANTHIA (PAN) can be repressed by interacting with CC-type glutaredoxins, which have the potential to control the redox state of target proteins. As TGA1 can be redox modulated in planta, we analyzed whether some of the 21 CC-type glutaredoxins (ROXYs) encoded in the Arabidopsis genome can influence TGA1 activity in planta and whether the redox active cysteines of TGA1 are functionally important. We show that the tga1 tga4 mutant and plants ectopically expressing ROXY8 or ROXY9 are impaired in hyponastic growth. As expression of ROXY8 and ROXY9 is activated upon transfer of plants from hyponasty-inducing low light to normal light, they might interfere with the growth-promoting function of TGA1/TGA4 to facilitate reversal of hyponastic growth. The redox-sensitive cysteines of TGA1 are not required for induction or reversal of hyponastic growth. TGA1 and TGA4 interact with ROXYs 8, 9, 18, and 19/GRX480, but ectopically expressed ROXY18 and ROXY19/GRX480 do not interfere with hyponastic growth. Our results therefore demonstrate functional specificities of individual ROXYs for distinct TGAs despite promiscuous protein-protein interactions and point to different repression mechanisms, depending on the TGA/ROXY combination.
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Affiliation(s)
- Ning Li
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Martin Muthreich
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Li-Jun Huang
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Corinna Thurow
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
| | - Tongjun Sun
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Yuelin Zhang
- Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Christiane Gatz
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
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Uhrig JF, Huang LJ, Barghahn S, Willmer M, Thurow C, Gatz C. CC-type glutaredoxins recruit the transcriptional co-repressor TOPLESS to TGA-dependent target promoters in Arabidopsis thaliana. Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms 2017; 1860:218-226. [DOI: 10.1016/j.bbagrm.2016.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 10/28/2016] [Accepted: 11/08/2016] [Indexed: 01/13/2023]
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Huang LJ, Li N, Thurow C, Wirtz M, Hell R, Gatz C. Ectopically expressed glutaredoxin ROXY19 negatively regulates the detoxification pathway in Arabidopsis thaliana. BMC Plant Biol 2016; 16:200. [PMID: 27624344 PMCID: PMC5022239 DOI: 10.1186/s12870-016-0886-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 09/01/2016] [Indexed: 05/20/2023]
Abstract
BACKGROUND Glutaredoxins (GRXs) are small proteins which bind glutathione to either reduce disulfide bonds or to coordinate iron sulfur clusters. Whereas these well-established functions are associated with ubiquitously occurring GRXs that encode variants of a CPYC or a CGFS motif in the active center, land plants also possess CCxC/S-type GRXs (named ROXYs) for which the biochemical functions are yet unknown. ROXYs physically and genetically interact with bZIP transcription factors of the TGA family. In Arabidopsis, ectopically expressed ROXY19 (originally named GRX480 or GRXC9) negatively regulates expression of jasmonic acid/ethylene-induced defense genes through an unknown mechanism that requires at least one of the redundant transcription factors TGA2, TGA5 or TGA6. RESULTS Ectopically expressed ROXY19 interferes with the activation of TGA-dependent detoxification genes. Similar to the tga2 tga5 tga6 mutant, 35S:ROXY19 plants are more susceptible to the harmful chemical TIBA (2,3,5-triiodobenzoic acid). The repressive function of ROXY19 depends on the integrity of the active site, which can be either CCMC or CPYC but not SSMS. Ectopic expression of the related GRX ROXY18/GRXS13 also led to increased susceptibility to TIBA, indicating potential functional redundancy of members of the ROXY gene family. This redundancy might explain why roxy19 knock-out plants did not show a phenotype with respect to the regulation of the TIBA-induced detoxification program. Complementation of the tga2 tga5 tga6 mutant with either TGA5 or TGA5C186S, in which the single potential target-site of ROXY19 had been eliminated, did not reveal any evidence for a critical redox modification that might be important for controlling the detoxification program. CONCLUSIONS ROXY19 and related proteins of the ROXY gene family can function as negative regulators of TGA-dependent promoters controlling detoxification genes.
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Affiliation(s)
- Li-Jun Huang
- Albrecht-von-Haller-Institute for Plant Sciences, Molecular Biology and Physiology, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Ning Li
- Albrecht-von-Haller-Institute for Plant Sciences, Molecular Biology and Physiology, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Corinna Thurow
- Albrecht-von-Haller-Institute for Plant Sciences, Molecular Biology and Physiology, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Markus Wirtz
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Rüdiger Hell
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Christiane Gatz
- Albrecht-von-Haller-Institute for Plant Sciences, Molecular Biology and Physiology, Georg-August-University Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
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Gutsche N, Thurow C, Zachgo S, Gatz C. Plant-specific CC-type glutaredoxins: functions in developmental processes and stress responses. Biol Chem 2015; 396:495-509. [DOI: 10.1515/hsz-2014-0300] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 03/02/2015] [Indexed: 01/25/2023]
Abstract
Abstract
Glutaredoxins (GRXs) are small oxidoreductases of the thioredoxin family proteins that can either regulate the thiol redox state of proteins or are linked to iron metabolism because of their ability to incorporate iron-sulfur [2Fe–2S] clusters. Here we review recent research on a land plant-specific class of GRX-like proteins, which are characterized by the conserved CC motif in the active centre. Loss-of-function mutants of CC-type GRXs in Arabidopsis (also named ROXYs), maize, and rice have unraveled a role in floral development, including regulation of organ primordia initiation, control of organ identity gene expression, and progression into meiosis in the male germ line. Other CC-type GRXs play a role in stress responses, most likely through their capacity to regulate nuclear gene expression. Consistently, CC-type GRXs, physically and genetically interact with individual members of the TGA transcription factor family. One of the challenges in the future is to unravel whether ROXYs control the redox state of TGA factors or other yet unknown target proteins or whether they regulate gene expression through other processes. Other intriguing questions concern the original function of the first CC-type GRXs in basal land plants and their potential contribution to the extremely successful radiation of angiosperms.
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Zander M, Thurow C, Gatz C. TGA Transcription Factors Activate the Salicylic Acid-Suppressible Branch of the Ethylene-Induced Defense Program by Regulating ORA59 Expression. Plant Physiol 2014; 165:1671-1683. [PMID: 24989234 PMCID: PMC4119047 DOI: 10.1104/pp.114.243360] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 06/26/2014] [Indexed: 05/18/2023]
Abstract
Salicylic acid (SA), a hormone essential for defense against biotrophic pathogens, triggers increased susceptibility of plants against necrotrophic attackers by suppressing the jasmonic acid-ethylene (ET) defense response. Here, we show that this disease-promoting SA effect is abolished in plants lacking the three related TGACG sequence-specific binding proteins TGA2, TGA5, and TGA6 (class II TGAs). After treatment of plants with the ET precursor 1-aminocyclopropane-1-carboxylic acid (ACC), activation of all those genes that are suppressed by SA depended on class II TGAs. Rather than TGA binding sites, GCC-box motifs were significantly enriched in the corresponding promoters. GCC-box motifs are recognized by members of the superfamily of APETALA2/ETHYLENE RESPONSE FACTORs (ERFs). Of 11 activating ACC-induced APETALA2/ERFs, only ORA59 (for OCTADECANOID-RESPONSIVE ARABIDOPSIS APETALA2/ETHYLENE RESPONSE FACTOR domain protein59) and ERF96 were strongly suppressed by SA. ORA59 is the master regulator of the jasmonic acid-ET-induced defense program. ORA59 transcript levels do not reach maximal levels in the tga2 tga5 tga6 triple mutant, and this residual activity cannot be suppressed by SA. The ORA59 promoter contains an essential TGA binding site and is a direct target of class II TGAs as revealed by chromatin immunoprecipitation experiments. We suggest that class II TGAs at the ORA59 promoter constitute an important regulatory hub for the activation and SA suppression of ACC-induced genes.
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Affiliation(s)
- Mark Zander
- Molecular Biology and Physiology of Plants, Albrecht-von-Haller-Institute, Georg-August-University Goettingen, D-37077 Goettingen, Germany
| | - Corinna Thurow
- Molecular Biology and Physiology of Plants, Albrecht-von-Haller-Institute, Georg-August-University Goettingen, D-37077 Goettingen, Germany
| | - Christiane Gatz
- Molecular Biology and Physiology of Plants, Albrecht-von-Haller-Institute, Georg-August-University Goettingen, D-37077 Goettingen, Germany
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König S, Feussner K, Kaever A, Landesfeind M, Thurow C, Karlovsky P, Gatz C, Polle A, Feussner I. Soluble phenylpropanoids are involved in the defense response of Arabidopsis against Verticillium longisporum. New Phytol 2014; 202:823-837. [PMID: 24483326 DOI: 10.1111/nph.12709] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 01/04/2014] [Indexed: 05/18/2023]
Abstract
Verticillium longisporum is a soil-borne vascular pathogen causing economic loss in rape. Using the model plant Arabidopsis this study analyzed metabolic changes upon fungal infection in order to identify possible defense strategies of Brassicaceae against this fungus. Metabolite fingerprinting identified infection-induced metabolites derived from the phenylpropanoid pathway. Targeted analysis confirmed the accumulation of sinapoyl glucosides, coniferin, syringin and lignans in leaves from early stages of infection on. At later stages, the amounts of amino acids increased. To test the contribution of the phenylpropanoid pathway, mutants in the pathway were analyzed. The sinapate-deficient mutant fah1-2 showed stronger infection symptoms than wild-type plants, which is most likely due to the lack of sinapoyl esters. Moreover, the coniferin accumulating transgenic plant UGT72E2-OE was less susceptible. Consistently, sinapoyl glucose, coniferyl alcohol and coniferin inhibited fungal growth and melanization in vitro, whereas sinapyl alcohol and syringin did not. The amount of lignin was not significantly altered supporting the notion that soluble derivatives of the phenylpropanoid pathway contribute to defense. These data show that soluble phenylpropanoids are important for the defense response of Arabidopsis against V. longisporum and that metabolite fingerprinting is a valuable tool to identify infection-relevant metabolic markers.
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Affiliation(s)
- Stefanie König
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Kirstin Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Alexander Kaever
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University, Goldschmidtstr. 1, 37077, Göttingen, Germany
| | - Manuel Landesfeind
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University, Goldschmidtstr. 1, 37077, Göttingen, Germany
| | - Corinna Thurow
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Julia-Lermontowa-Weg 3, 37077, Göttingen, Germany
| | - Petr Karlovsky
- Department of Molecular Phytopathology and Mycotoxin Research, Faculty of Agricultural Sciences, Georg-August-University, Grisebachstr. 6, 37077, Göttingen, Germany
| | - Christiane Gatz
- Department of Plant Molecular Biology and Physiology, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Julia-Lermontowa-Weg 3, 37077, Göttingen, Germany
| | - Andrea Polle
- Department of Forest Botany and Tree Physiology, Büsgen-Institute, Georg-August-University, Büsgenweg 2, 37077, Göttingen, Germany
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
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Landesfeind M, Kaever A, Feussner K, Thurow C, Gatz C, Feussner I, Meinicke P. Integrative study of Arabidopsis thaliana metabolomic and transcriptomic data with the interactive MarVis-Graph software. PeerJ 2014; 2:e239. [PMID: 24688832 PMCID: PMC3961162 DOI: 10.7717/peerj.239] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 12/17/2013] [Indexed: 11/20/2022] Open
Abstract
State of the art high-throughput technologies allow comprehensive experimental studies of organism metabolism and induce the need for a convenient presentation of large heterogeneous datasets. Especially, the combined analysis and visualization of data from different high-throughput technologies remains a key challenge in bioinformatics. We present here the MarVis-Graph software for integrative analysis of metabolic and transcriptomic data. All experimental data is investigated in terms of the full metabolic network obtained from a reference database. The reactions of the network are scored based on the associated data, and sub-networks, according to connected high-scoring reactions, are identified. Finally, MarVis-Graph scores the detected sub-networks, evaluates them by means of a random permutation test and presents them as a ranked list. Furthermore, MarVis-Graph features an interactive network visualization that provides researchers with a convenient view on the results. The key advantage of MarVis-Graph is the analysis of reactions detached from their pathways so that it is possible to identify new pathways or to connect known pathways by previously unrelated reactions. The MarVis-Graph software is freely available for academic use and can be downloaded at: http://marvis.gobics.de/marvis-graph.
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Affiliation(s)
- Manuel Landesfeind
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University , Göttingen , Germany
| | - Alexander Kaever
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University , Göttingen , Germany
| | - Kirstin Feussner
- Department for Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University , Göttingen , Germany
| | - Corinna Thurow
- Department for Plant Molecular Biology and Physiology, Schwann-Schleiden-Research-Center for Molecular Cell Biology, Georg-August-University , Göttingen , Germany
| | - Christiane Gatz
- Department for Plant Molecular Biology and Physiology, Schwann-Schleiden-Research-Center for Molecular Cell Biology, Georg-August-University , Göttingen , Germany
| | - Ivo Feussner
- Department for Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University , Göttingen , Germany
| | - Peter Meinicke
- Department of Bioinformatics, Institute of Microbiology and Genetics, Georg-August-University , Göttingen , Germany
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Ralhan A, Thurow C, Gatz C. The tolerance of the Arabidopsis defense hormone receptor mutant coi1 against the vascular pathogen Verticillium longisporum is not due to increased levels of the active hormone jasmonoyl-isoleucine. Plant Signal Behav 2013; 8:e27008. [PMID: 24300304 PMCID: PMC4091333 DOI: 10.4161/psb.27008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Verticillium longisporum is a soil-borne vascular pathogen found primarily on oilseed rape in Northern Europe. Infection of the model plant Arabidopsis thaliana can be achieved under laboratory conditions. In the article related to this addendum, we have shown that Arabidopsis dde2-2 mutants that are compromised in their ability to synthesize the defense hormone jasmonoyl-isoleucine (JA-Ile) are slightly more susceptible than wild-type. Contrary to the expectation that hormone biosynthesis mutants and their respective receptor mutants should have the same phenotype, we found that plants that lack the JA-Ile receptor CORONATINE INSENSITIVE1 (COI1) are more tolerant to the disease. This addendum addressed the question whether the increased JA-Ile levels found in coi1 are responsible for its tolerance phenotype. Based on the evidence that the JA-Ile-deficient dde2-2 coi1-t double mutant is as tolerant as coi1-t, we conclude that increased JA-Ile levels do not protect Arabidopsis against the fungus in the absence of COI1.
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Ralhan A, Schöttle S, Thurow C, Iven T, Feussner I, Polle A, Gatz C. The vascular pathogen Verticillium longisporum requires a jasmonic acid-independent COI1 function in roots to elicit disease symptoms in Arabidopsis shoots. Plant Physiol 2012; 159:1192-203. [PMID: 22635114 PMCID: PMC3387704 DOI: 10.1104/pp.112.198598] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 05/19/2012] [Indexed: 05/18/2023]
Abstract
Verticillium longisporum is a soil-borne vascular pathogen that causes reduced shoot growth and early senescence in Arabidopsis (Arabidopsis thaliana). Here, we report that these disease symptoms are less pronounced in plants that lack the receptor of the plant defense hormone jasmonic acid (JA), CORONATINE INSENSITIVE1 (COI1). Initial colonization of the roots was comparable in wild-type and coi1 plants, and fungal DNA accumulated to almost similar levels in petioles of wild-type and coi1 plants at 10 d post infection. Completion of the fungal life cycle was impaired in coi1, as indicated by the reduced number of plants with microsclerotia, which are detected on dead plant material at late stages of the disease. Contrary to the expectation that the hormone receptor mutant coi1 should display the same phenotype as the corresponding hormone biosynthesis mutant delayed dehiscence2 (dde2), dde2 plants developed wild-type-like disease symptoms. Marker genes of the JA and the JA/ethylene defense pathway were induced in petioles of wild-type plants but not in petioles of dde2 plants, indicating that fungal compounds that would activate the known COI1-dependent signal transduction chain were absent. Grafting experiments revealed that the susceptibility-enhancing COI1 function acts in the roots. Moreover, we show that the coi1-mediated tolerance is not due to the hyperactivation of the salicylic acid pathway. Together, our results have unraveled a novel COI1 function in the roots that acts independently from JA-isoleucine or any JA-isoleucine mimic. This COI1 activity is required for a yet unknown root-to-shoot signaling process that enables V. longisporum to elicit disease symptoms in Arabidopsis.
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Zander M, Chen S, Imkampe J, Thurow C, Gatz C. Repression of the Arabidopsis thaliana jasmonic acid/ethylene-induced defense pathway by TGA-interacting glutaredoxins depends on their C-terminal ALWL motif. Mol Plant 2012; 5:831-40. [PMID: 22207719 DOI: 10.1093/mp/ssr113] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Glutaredoxins are small heat-stable oxidoreductases that transfer electrons from glutathione (GSH) to oxidized cysteine residues, thereby contributing to protein integrity and regulation. In Arabidopsis thaliana, floral glutaredoxins ROXY1 and ROXY2 and pathogen-induced ROXY19/GRX480 interact with bZIP transcription factors of the TGACG (TGA) motif-binding family. ROXY1, ROXY2, and TGA factors PERIANTHIA, TGA9, and TGA10 play essential roles in floral development. In contrast, ectopically expressed ROXY19/GRX480 negatively regulates expression of jasmonic acid (JA)/ethylene (ET)-induced defense genes through an unknown mechanism that requires clade II transcription factors TGA2, TGA5, and/or TGA6. Here, we report that at least 17 of the 21 land plant-specific glutaredoxins encoded in the Arabidopsis genome interact with TGA2 in a yeast-two-hybrid system. To investigate their capacity to interfere with the expression of JA/ET-induced genes, we developed a transient expression system. Activation of the ORA59 (OCTADECANOID-RESPONSIVE ARABIDOPSIS AP2/ERF-domain protein 59) promoter by transcription factor EIN3 (ETHYLENE INSENSITVE 3) was suppressed by co-expressed ROXY19/GRX480. Suppression depended on the L**LL motif in the C-terminus of ROXY19/GRX480. This putative protein interaction domain was recently described as being essential for the TGA/ROXY interaction. Ten of the 17 tested ROXY proteins suppressed ORA59 promoter activity, which correlated with the presence of the C-terminal ALWL motif, which is essential for ROXY1 function in flower development. ROXY19/GRX480-mediated repression depended on the GSH binding site, suggesting that redox modification of either TGA factors or as yet unknown target proteins is important for the suppression of ORA59 promoter activity.
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Affiliation(s)
- Mark Zander
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Göttingen, Germany
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Köster J, Thurow C, Kruse K, Meier A, Iven T, Feussner I, Gatz C. Xenobiotic- and jasmonic acid-inducible signal transduction pathways have become interdependent at the Arabidopsis CYP81D11 promoter. Plant Physiol 2012; 159:391-402. [PMID: 22452854 PMCID: PMC3375972 DOI: 10.1104/pp.112.194274] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plants modify harmful substances through an inducible detoxification system. In Arabidopsis (Arabidopsis thaliana), chemical induction of the cytochrome P450 gene CYP81D11 and other genes linked to the detoxification program depends on class II TGA transcription factors. CYP81D11 expression is also induced by the phytohormone jasmonic acid (JA) through the established pathway requiring the JA receptor CORONATINE INSENSITIVE1 (COI1) and the JA-regulated transcription factor MYC2. Here, we report that the xenobiotic- and the JA-dependent signal cascades have become interdependent at the CYP81D11 promoter. On the one hand, MYC2 can only activate the expression of CYP81D11 when both the MYC2- and the TGA-binding sites are present in the promoter. On the other hand, the xenobiotic-regulated class II TGA transcription factors can only mediate maximal promoter activity if TGA and MYC2 binding motifs, MYC2, and the JA-isoleucine biosynthesis enzymes DDE2/AOS and JAR1 are functional. Since JA levels and degradation of JAZ1, a repressor of the JA response, are not affected by reactive chemicals, we hypothesize that basal JA signaling amplifies the response to chemical stress. Remarkably, stress-induced expression levels were 3-fold lower in coi1 than in the JA biosynthesis mutant dde2-2, [corrected] revealing that COI1 can contribute to the activation of the promoter in the absence of JA. Moreover, we show that deletion of the MYC2 binding motifs abolishes the JA responsiveness of the promoter but not the responsiveness to COI1. These findings suggest that yet unknown cis-element(s) can mediate COI1-dependent transcriptional activation in the absence of JA.
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La Camera S, L'haridon F, Astier J, Zander M, Abou-Mansour E, Page G, Thurow C, Wendehenne D, Gatz C, Métraux JP, Lamotte O. The glutaredoxin ATGRXS13 is required to facilitate Botrytis cinerea infection of Arabidopsis thaliana plants. Plant J 2011; 68:507-19. [PMID: 21756272 DOI: 10.1111/j.1365-313x.2011.04706.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Botrytis cinerea is a major pre- and post-harvest necrotrophic pathogen with a broad host range that causes substantial crop losses. The plant hormone jasmonic acid (JA) is involved in the basal resistance against this fungus. Despite basal resistance, virulent strains of B. cinerea can cause disease on Arabidopsis thaliana and virulent pathogens can interfere with the metabolism of the host in a way to facilitate infection of the plant. However, plant genes that are required by the pathogen for infection remain poorly described. To find such genes, we have compared the changes in gene expression induced in A. thaliana by JA with those induced after B. cinerea using genome-wide microarrays. We have identified genes that are repressed by JA but that are induced by B. cinerea. In this study, we describe one candidate gene, ATGRXS13, that encodes for a putative glutaredoxin and that exhibits such a crossed expression. In plants that are infected by this necrotrophic fungus, ATGRXS13 expression was negatively controlled by JA and TGA transcription factors but also through a JA-salicylic acid (SA) cross-talk mechanism as B. cinerea induced SA production that positively controlled ATGRXS13 expression. Furthermore, plants impaired in ATGRXS13 exhibited resistance to B. cinerea. Finally, we present a model whereby B. cinerea takes advantage of defence signalling pathways of the plant to help the colonization of its host.
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Affiliation(s)
- Sylvain La Camera
- Département de Biologie, Université de Fribourg, 10 chemin du Musée, CH-1700 Fribourg, Germany
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Abstract
Plant responses to wounding are part of their defense responses against insects, and are tightly regulated. The isoleucin conjugate of jasmonic acid (JA-Ile) is a major regulatory molecule. We have previously shown that inositol polyphosphate signals are required for defense responses in Arabidopsis; however, the way in which inositol polyphosphates contribute to plant responses to wounding has so far remained unclear. Arabidopsis F-box proteins involved in the perception of JA-Ile (COI1) and auxin (TIR1) are structurally similar. Because TIR1 has recently been shown to contain inositol hexakisphosphate (InsP₆) as a co-factor of unknown function, here we explored the possibility that InsP₆ or another inositol polyphosphate is required for COI1 function. In support of this hypothesis, COI1 variants with changes in putative inositol polyphosphate coordinating residues exhibited a reduced interaction with the COI1 target, JAZ9, in yeast two-hybrid tests. The equivalent COI1 variants displayed a reduced capability to rescue jasmonate-mediated root growth inhibition or silique development in Arabidopsis coi1 mutants. Yeast two-hybrid tests using wild-type COI1 in an ipk1Δ yeast strain exhibiting increased levels of inositol pentakisphosphate (InsP₅) and reduced levels of InsP₆ indicate an enhanced COI1/JAZ9 interaction. Consistent with these findings, Arabidopsis ipk1-1 mutants, also with increased InsP₅ and reduced InsP₆ levels, showed increased defensive capabilities via COI1-mediated processes, including wound-induced gene expression, defense against caterpillars or root growth inhibition by jasmonate. The combined data from experiments using mutated COI1 variants, as well as yeast and Arabidopsis backgrounds altered in inositol polyphosphate metabolism, indicate that an inositol polyphosphate, and probably InsP₅, contributes to COI1 function.
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Affiliation(s)
- Alina Mosblech
- Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
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Pape S, Thurow C, Gatz C. Exchanging the as-1-like element of the PR-1 promoter by the as-1 element of the CaMV 35S promoter abolishes salicylic acid responsiveness and regulation by NPR1 and SNI1. Plant Signal Behav 2010; 5:1669-1671. [PMID: 21139438 PMCID: PMC3115131 DOI: 10.4161/psb.5.12.14033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 10/26/2010] [Indexed: 05/30/2023]
Abstract
The plant defense hormone salicylic acid (SA) activates gene expression through a number of different mechanisms. In Arabidopsis thaliana, the SA-induced PATHOGENESIS RELATED (PR)-1 promoter is regulated through TGA transcription factors binding to the two TGACG motifs of the so called as-1 (activation sequence-1)-like element which is located between base pair positions -665 and -641. Activation is mediated by the transcriptional co-activator NPR1 (NON EXPRESSOR OF PR GENES1), which physically interacts with TGA factors. Moreover, the promoter is under the control of the negative regulator SNI1 (SUPPRESSOR OF NPR1, INDUCIBLE1). We have recently reported that SNI1-mediated repression of basal promoter activities and NPR1-dependent induction are maintained in a truncated PR-1 promoter that contains sequences between -816 and -573 upstream of the -68 promoter region. In this addendum, we report that the expression characteristics of this truncated PR-1 promoter is changed profoundly when its as-1-like element is replaced by the as-1 element of Cauliflower Mosaic Virus 35S promoter which also contains two TGACG motifs. The resulting chimeric promoter showed high constitutive activity that was independent from SA, NPR1 and SNI1. Thus, the configuration of two TGA binding sites within the PR-1 promoter determines whether NPR1 can induce and whether SNI1 can repress the promoter.
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Affiliation(s)
- Sebastian Pape
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Göttingen, Germany
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Pape S, Thurow C, Gatz C. The Arabidopsis PR-1 promoter contains multiple integration sites for the coactivator NPR1 and the repressor SNI1. Plant Physiol 2010; 154:1805-18. [PMID: 20935179 PMCID: PMC2996008 DOI: 10.1104/pp.110.165563] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Accepted: 10/05/2010] [Indexed: 05/21/2023]
Abstract
Systemic acquired resistance is a broad-spectrum plant immune response involving massive transcriptional reprogramming. The Arabidopsis (Arabidopsis thaliana) PATHOGENESIS-RELATED-1 (PR-1) gene has been used in numerous studies to elucidate transcriptional control mechanisms regulating systemic acquired resistance. WRKY transcription factors and basic leucine zipper proteins of the TGA family regulate the PR-1 promoter by binding to specific cis-elements. In addition, the promoter is under the control of two proteins that do not directly contact the DNA: the positive regulator NONEXPRESSOR OF PR GENES1 (NPR1), which physically interacts with TGA factors, and the repressor SUPPRESSOR OF NPR1, INDUCIBLE1 (SNI1). In this study, we analyzed the importance of the TGA-binding sites LS5 and LS7 and the WKRY box LS4 for regulation by NPR1 and SNI1. In the absence of LS5 and LS7, NPR1 activates the PR-1 promoter through a mechanism that requires LS4. Since transcriptional activation of WRKY genes is under the control of NPR1 and since LS4 is not sufficient for the activation of a truncated PR-1 promoter by the effector protein NPR1-VP16 in transient assays, it is concluded that the LS4-dependent activation of the PR-1 promoter is indirect. In the case of NPR1 acting directly through TGA factors at its target promoters, two TGA-binding sites are necessary but not sufficient for NPR1 function in transgenic plants and in the NPR-VP16-based trans-activation assay in protoplasts. SNI1 exerts its negative effect in the noninduced state by targeting unknown proteins associated with sequences between bp -816 and -573. Under induced conditions, SNI1 negatively regulates the function of WRKY transcription factors binding to WKRY boxes between bp -550 and -510.
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Islam KMD, Dilcher M, Thurow C, Vock C, Krimmelbein IK, Tietze LF, Gonzalez V, Zhao H, Gatz C. Directed evolution of estrogen receptor proteins with altered ligand-binding specificities. Protein Eng Des Sel 2009; 22:45-52. [DOI: 10.1093/protein/gzn067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Fode B, Siemsen T, Thurow C, Weigel R, Gatz C. The Arabidopsis GRAS protein SCL14 interacts with class II TGA transcription factors and is essential for the activation of stress-inducible promoters. Plant Cell 2008; 20:3122-35. [PMID: 18984675 PMCID: PMC2613660 DOI: 10.1105/tpc.108.058974] [Citation(s) in RCA: 171] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Revised: 10/10/2008] [Accepted: 10/24/2008] [Indexed: 05/17/2023]
Abstract
The plant signaling molecule salicylic acid (SA) and/or xenobiotic chemicals like the auxin mimic 2,4-D induce transcriptional activation of defense- and stress-related genes that contain activation sequence-1 (as-1)-like cis-elements in their promoters. as-1-like sequences are recognized by basic/leucine zipper transcription factors of the TGA family. Expression of genes related to the SA-dependent defense program systemic acquired resistance requires the TGA-interacting protein NPR1. However, a number of as-1-containing promoters can be activated independently from NPR1. Here, we report the identification of Arabidopsis thaliana SCARECROW-like 14 (SCL14), a member of the GRAS family of regulatory proteins, as a TGA-interacting protein that is required for the activation of TGA-dependent but NPR1-independent SA- and 2,4-D-inducible promoters. Chromatin immunoprecipitation experiments revealed that class II TGA factors TGA2, TGA5, and/or TGA6 are needed to recruit SCL14 to promoters of selected SCL14 target genes identified by whole-genome transcript profiling experiments. The coding regions and the expression profiles of the SCL14-dependent genes imply that they might be involved in the detoxification of xenobiotics and possibly endogenous harmful metabolites. Consistently, plants ectopically expressing SCL14 showed increased tolerance to toxic doses of the chemicals isonicotinic acid and 2,4,6-triiodobenzoic acid, whereas the scl14 and the tga2 tga5 tga6 mutants were more susceptible. Hence, the TGA/SCL14 complex seems to be involved in the activation of a general broad-spectrum detoxification network upon challenge of plants with xenobiotics.
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Affiliation(s)
- Benjamin Fode
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, D-37073 Göttingen, Germany
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Ndamukong I, Abdallat AA, Thurow C, Fode B, Zander M, Weigel R, Gatz C. SA-inducible Arabidopsis glutaredoxin interacts with TGA factors and suppresses JA-responsive PDF1.2 transcription. Plant J 2007; 50:128-39. [PMID: 17397508 DOI: 10.1111/j.1365-313x.2007.03039.x] [Citation(s) in RCA: 264] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Salicylic acid (SA) is a plant signaling molecule that mediates the induction of defense responses upon attack by a variety of pathogens. Moreover, it antagonizes gene induction by the stress signaling molecule jasmonic acid (JA). Several SA-responsive genes are regulated by basic/leucine zipper-type transcription factors of the TGA family. TGA factors interact with NPR1, a central regulator of many SA-induced defense responses including SA/JA antagonism. In order to identify further regulatory proteins of SA-dependent signaling pathways, a yeast protein interaction screen with tobacco TGA2.2 as bait and an Arabidopsis thaliana cDNA prey library was performed and led to the identification of a member of the glutaredoxin family (GRX480, encoded by At1g28480). Glutaredoxins are candidates for mediating redox regulation of proteins because of their capacity to catalyze disulfide transitions. This agrees with previous findings that the redox state of both TGA1 and NPR1 changes under inducing conditions. Transgenic Arabidopsis plants ectopically expressing GRX480 show near wild-type expression of standard marker genes for SA- and xenobiotic-inducible responses. In contrast, transcription of the JA-dependent defensin gene PDF1.2 was antagonized by transgenic GRX480. This, together with the observation that GRX480 transcription is SA-inducible and requires NPR1, suggests a role of GRX480 in SA/JA cross-talk. Suppression of PDF1.2 by GRX480 depends on the presence of TGA factors, indicating that the GRX480/TGA interaction is effective in planta.
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Affiliation(s)
- Ivan Ndamukong
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Untere Karspüle 2, D-37073 Göttingen, Germany
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Butterbrodt T, Thurow C, Gatz C. Chromatin immunoprecipitation analysis of the tobacco PR-1a- and the truncated CaMV 35S promoter reveals differences in salicylic acid-dependent TGA factor binding and histone acetylation. Plant Mol Biol 2006; 61:665-74. [PMID: 16897482 DOI: 10.1007/s11103-006-0039-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Accepted: 03/07/2006] [Indexed: 05/11/2023]
Abstract
Salicylic acid (SA) is a plant signalling molecule needed for the induction of defence responses upon attack by a variety of pathogens. Truncation of the Cauliflower Mosaic Virus (CaMV) 35S promoter down to 90 bp has identified activation sequence-1 (as-1) as an autonomous SA-responsive cis element. The as-1-like elements are found in a number of SA-inducible promoters like e.g. the tobacco PR-1a promoter. They are recognized by basic/leucine zipper (bZIP) transcription factors of the TGA family. In tobacco leaves, TGA2.2 is the most abundant TGA factor. TGA2.2 is required for the expression of as-1-containing promoters. Here we unravel clear differences between the "truncated" CaMV 35S and the PR-1a promoter with respect to in vivo TGA binding and histone acetylation. Chromatin immunoprecipitation (ChIP) analysis revealed SA-inducible recruitment of tobacco TGA2.2 as well as SA-inducible histone acetylation at the PR-1a promoter. In contrast, no influence of SA on TGA2.2 binding and histone acetylation was detectable at the "truncated" CaMV 35S promoter. The finding of SA-independent TGA factor binding in the absence of additional flanking regulatory sequences suggests that transcriptional activation is not necessarily mediated by inducible DNA binding of TGA factors. Plants with severely reduced TGA2.2 protein levels also showed SA-induced histone acetylation at the PR-1a promoter indicating that regulatory events independent from TGA2.2 function are initiated at the PR-1a promoter.
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Affiliation(s)
- Thomas Butterbrodt
- Albrecht-von-Haller-Institut fuer Pflanzenwissenschaften, Georg-August-Universitaet Goettingen, Untere Karspuele 2, 37073 Goettingen, Germany
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Thurow C, Schiermeyer A, Krawczyk S, Butterbrodt T, Nickolov K, Gatz C. Tobacco bZIP transcription factor TGA2.2 and related factor TGA2.1 have distinct roles in plant defense responses and plant development. Plant J 2005; 44:100-13. [PMID: 16167899 DOI: 10.1111/j.1365-313x.2005.02513.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Salicylic acid (SA) is a crucial internal signaling molecule needed for the induction of plant defense responses upon attack of a variety of pathogens. Basic leucine zipper transcription factors of the TGA family bind to activating sequence-1 (as-1)-like elements which are SA-responsive cis elements found in promoters of 'immediate early' and 'late' SA-inducible genes. TGA2.2 constitutes the main component of tobacco as-1-binding factor-1 (ASF-1). TGA2.1, which differs from TGA2.2 by being able to activate transcription in yeast, constitutes a minor fraction of the complex. Both proteins interact with NPR1, a protein essential for SA inducibility of 'late' genes. Here we demonstrate using dsRNAi mediated gene silencing that reducing the amount of TGA2.2 and TGA2.1 correlates with a significant decrease in ASF-1 activity and with a decreased inducibility of both 'immediate early' and 'late' genes. In contrast, reducing the amount of TGA2.1 alone had no effect on the expression of these target genes suggesting that TGA2.1 is dispensable for SA-inducible gene expression from the as-1 element. Expression of a TGA2.2 mutant unable to form heterodimers with the endogenous pool of TGA factors led to reduced SA-inducibility of 'immediate early' gene Nt103, indicating that the native leucine zipper is important for the protein to act positively on transcription. Plants with reduced amounts of TGA2.1 developed petal like stamens indicating a regulatory role of TGA2.1 in defining organ identity in tobacco flowers. A model is suggested that unifies conflicting results on the function of tobacco TGA factors with respect to activation of the 'late' PR-1a promoter.
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Affiliation(s)
- Corinna Thurow
- Albrecht-von-Haller-Institut fuer Pflanzenwissenschaften, Universitaet Goettingen, Untere Karspuele 2, 37073 Goettingen, Germany
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26
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Abstract
TGA factors constitute a family of conserved plant bZ1P transcription factors that regulate transcription from as-1-like elements in response to plant signalling molecules salicylic acid (SA), methyl jasmonate (MJ) and auxin. Based on sequence similarities, two subclasses of TGA factors have been identified before in tobacco: class I factors (TGA1a and PG13) are preferentially expressed in root tip meristems, whereas class II factors (TGA2.1 and TGA2.2) are found in leaves and in roots. Here we describe a novel member of the tobacco TGA family (TGA10), which defines a distinct subclass of its own. TGA10 mRNA and TGA10 protein were found in roots but not in leaves of mature tobacco plants. TGA10 binds specifically to the as-1 element, interacts with TGA2.2, and activates transcription in yeast. When ectopically expressed in leaves, TGA10 enhanced SA-, auxin- and MJ-inducibility of target gene Nt103, which responds in the same manner to enhanced levels of TGA2.2. This indicates that TGA10, albeit normally not present in leaves, can interact with the leaf regulatory network controlling transcription from as-1-containing promoters. However, Nt103 expression was not affected in roots of TGA10-over-expressing plants, implying the existence of root-specific mechanisms which do not allow a positive effect of increased TGA10 levels on target gene expression.
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MESH Headings
- Acetates/pharmacology
- Amino Acid Sequence
- Binding Sites/genetics
- Blotting, Northern
- Cyclopentanes/pharmacology
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Electrophoretic Mobility Shift Assay
- Gene Expression Regulation, Plant/drug effects
- Glucuronidase/genetics
- Glucuronidase/metabolism
- Indoleacetic Acids/pharmacology
- Molecular Sequence Data
- Multigene Family/genetics
- Oligonucleotides/genetics
- Oligonucleotides/metabolism
- Oxylipins
- Plant Leaves/genetics
- Plant Leaves/metabolism
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plant Roots/drug effects
- Plant Roots/genetics
- Plant Roots/metabolism
- Plants, Genetically Modified
- Protein Binding
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Saccharomyces cerevisiae/genetics
- Salicylic Acid/pharmacology
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Nicotiana/genetics
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcriptional Activation
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Affiliation(s)
- Andreas Schiermeyer
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Untere Karspüle 2, 37073 Göttingen, Germany
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27
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Krawczyk S, Thurow C, Niggeweg R, Gatz C. Analysis of the spacing between the two palindromes of activation sequence-1 with respect to binding to different TGA factors and transcriptional activation potential. Nucleic Acids Res 2002; 30:775-81. [PMID: 11809891 PMCID: PMC100291 DOI: 10.1093/nar/30.3.775] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2001] [Revised: 11/19/2001] [Accepted: 11/29/2001] [Indexed: 11/12/2022] Open
Abstract
In higher plants, activation sequence-1 (as-1) of the cauliflower mosaic virus 35S promoter mediates both salicylic acid- and auxin-inducible transcriptional activation. Originally found in viral and T-DNA promoters, as-1-like elements are also functional elements of plant promoters activated in the course of a defence response upon pathogen attack. as-1-like elements are characterised by two imperfect palindromes with the palindromic centres being spaced by 12 bp. They are recognised by plant nuclear as-1-binding factor ASF-1, the major component of which is basic/leucine zipper (bZIP) protein TGA2.2 (approximately 80%) in Nicotiana tabacum. In electrophoretic mobility shift assays, ASF-1 as well as bZIP proteins TGA2.2, TGA2.1 and TGA1a showed a 3-10-fold reduced binding affinity to mutant as-1 elements encoding insertions of 2, 4, 6, 8 or 10 bp between the palindromes, respectively. This correlated with a 5-10-fold reduction in transcriptional activation from these elements in transient expression assays. Although ASF-1 and TGA factors bound efficiently to a mutant element carrying a 2 bp deletion between the palindromes [as-1/(-2)], the latter was strongly compromised with respect to mediating gene expression in vivo. A fusion protein consisting of TGA2.2 and a constitutive activation domain mediated transactivation from as-1/(-2) demonstrating binding of TGA factors in vivo. We therefore conclude that both DNA binding and transactivation require optimal positioning of TGA factors on the as-1 element.
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Affiliation(s)
- Stefanie Krawczyk
- Albrecht-von-Haller-Institut fuer Pflanzenwissenschaften, Universitaet Goettingen, Untere Karspuele 2, 37073 Goettingen, Germany
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28
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Broderick T, Long P, Thurow C, Nguyen Q. Chronic food restriction restores the cardioprotective effect of ischemic preconditioning in the aging rat heart. J Mol Cell Cardiol 2001. [DOI: 10.1016/s0022-2828(01)90623-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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29
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Niggeweg R, Thurow C, Kegler C, Gatz C. Tobacco transcription factor TGA2.2 is the main component of as-1-binding factor ASF-1 and is involved in salicylic acid- and auxin-inducible expression of as-1-containing target promoters. J Biol Chem 2000; 275:19897-905. [PMID: 10751419 DOI: 10.1074/jbc.m909267199] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In higher plants, activating sequence-1 (as-1) of the cauliflower mosaic virus 35 S promoter mediates both salicylic acid (SA)- and auxin-inducible transcriptional activation. Originally found in promoters of several viral and bacterial plant pathogens, as-1-like elements are also functional elements of plant promoters activated in the course of a defense response upon pathogen attack. Nuclear as-1-binding factor (ASF-1) and cellular salicylic acid response protein (SARP) bind specifically to as-1. Four different tobacco bZIP transcription factors (TGA1a, PG13, TGA2.1, and TGA2.2) are potential components of either ASF-1 or SARP. Here we show that ASF-1 and SARP are very similar in their composition. TGA2.2 is a major component of either complex, as shown by supershift analysis and Western blot analysis of DNA affinity-purified SARP. Minor amounts of a protein immunologically related to TGA2.1 were detected, whereas TGA1a was not detectable. Overexpression of either TGA2.2 or a dominant negative TGA2.2 mutant affected both SA and auxin (2, 4D) inducibility of various target promoters encoding as-1-like elements, albeit to different extents. This indicates that TGA2.2 is a component of the enhancosome assembling on these target promoters, both under elevated SA and 2,4D concentrations. However, the effect of altered TGA2.2 levels on gene expression was more pronounced upon SA treatment than upon 2,4D treatment.
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MESH Headings
- Alleles
- Basic-Leucine Zipper Transcription Factors
- Blotting, Northern
- Blotting, Western
- Cell Nucleus/metabolism
- Cells, Cultured
- DNA-Binding Proteins/chemistry
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- DNA-Binding Proteins/physiology
- Escherichia coli/metabolism
- Gene Expression Regulation
- Gene Expression Regulation, Plant
- Genes, Dominant
- Glucuronidase/metabolism
- Indoleacetic Acids/pharmacology
- Mutation
- Plant Proteins/metabolism
- Plants, Genetically Modified/genetics
- Plants, Toxic
- Promoter Regions, Genetic
- Protein Biosynthesis
- Protein Structure, Tertiary
- Recombinant Proteins/metabolism
- Salicylic Acid/pharmacology
- Time Factors
- Nicotiana/chemistry
- Nicotiana/metabolism
- Transcription Factors/chemistry
- Transcription Factors/genetics
- Transcription Factors/physiology
- Transcription, Genetic
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Affiliation(s)
- R Niggeweg
- Albrecht-von-Haller-Institut fuer Pflanzenwissenschaften, Universitaet Goettingen, Untere Karspuele 2, 37073 Goettingen, Germany
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30
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Niggeweg R, Thurow C, Weigel R, Pfitzner U, Gatz C. Tobacco TGA factors differ with respect to interaction with NPR1, activation potential and DNA-binding properties. Plant Mol Biol 2000; 42:775-88. [PMID: 10809449 DOI: 10.1023/a:1006319113205] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In higher plants, as-1-like cis elements mediate auxin- and salicylic acid-inducible transcription. Originally found in viral and T-DNA promoters, they are also functional elements of plant promoters activated during the defence response against pathogens. Tobacco bZIP transcription factor TGA1a was the first recombinant protein shown to bind to as-1. cDNAs for two novel tobacco as-1-binding bZIP proteins (TGA2.1 and TGA2.2) were isolated. Revealing a high degree of amino acid identity in the bZIP domain (89%) and the C-terminus (79%), the two TGA2 factors differ remarkably with respect to the length of the N-terminus (170 amino acids in TGA2.1 versus 43 amino acids in TGA2.2). TGA2.1 and TGA2.2, but not TGA1a, interacted with ankyrin repeat protein NPR1, a central activator of the plant defence response. In contrast, TGA2.1 and TGA1a, but not TGA2.2, functioned as transcriptional activators in yeast. Apart from conferring transcriptional activation, the N-terminal domain of TGA2.1 led to reduced in vitro as-1-binding activity and almost completely abolished binding to one half site of this bifunctional element. When being part of a heterodimer with TGA2.2, TGA2.1 was efficiently recruited to a single half site, though double occupancy of the element was still preferred. In contrast, TGA1a preferred to bind to only one palindrome, a feature that was also maintained in heterodimers between TGA1a and TGA2.1 or TGA2.2.
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MESH Headings
- Amino Acid Sequence
- Arabidopsis Proteins
- Blotting, Northern
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Dimerization
- Gene Expression Regulation, Plant
- Lac Operon/genetics
- Molecular Sequence Data
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plants, Toxic
- Promoter Regions, Genetic/genetics
- Protein Binding
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Saccharomyces cerevisiae/genetics
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tissue Distribution
- Nicotiana/genetics
- Nicotiana/metabolism
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcriptional Activation
- Two-Hybrid System Techniques
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Affiliation(s)
- R Niggeweg
- Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Georg-August-Universität Göttingen, Germany
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