RRC ID 3079
著者 Zheng Z, Mosher SL, Fan B, Klessig DF, Chen Z.
タイトル Functional analysis of Arabidopsis WRKY25 transcription factor in plant defense against Pseudomonas syringae.
ジャーナル BMC Plant Biol
Abstract BACKGROUND:A common feature of plant defense responses is the transcriptional regulation of a large number of genes upon pathogen infection or treatment with pathogen elicitors. A large body of evidence suggests that plant WRKY transcription factors are involved in plant defense including transcriptional regulation of plant host genes in response to pathogen infection. However, there is only limited information about the roles of specific WRKY DNA-binding transcription factors in plant defense.
RESULTS:We analyzed the role of the WRKY25 transcription factor from Arabidopsis in plant defense against the bacterial pathogen Pseudomonas syringae. WRKY25 protein recognizes the TTGACC W-box sequences and its translational fusion with green fluorescent protein is localized to the nucleus. WRKY25 expression is responsive to general environmental stress. Analysis of stress-induced WRKY25 in the defense signaling mutants npr1, sid2, ein2 and coi1 further indicated that this gene is positively regulated by the salicylic acid (SA) signaling pathway and negatively regulated by the jasmonic acid signaling pathway. Two independent T-DNA insertion mutants for WRKY25 supported normal growth of a virulent strain of P. syringae but developed reduced disease symptoms after infection. By contrast, Arabidopsis constitutively overexpressing WRKY25 supported enhanced growth of P. syringae and displayed increased disease symptom severity as compared to wild-type plants. These WRKY25-overexpressing plants also displayed reduced expression of the SA-regulated PR1 gene after the pathogen infection, despite normal levels of free SA.
CONCLUSION:The nuclear localization and sequence-specific DNA-binding activity support that WRKY25 functions as a transcription factor. Based on analysis of both T-DNA insertion mutants and transgenic overexpression lines, stress-induced WRKY25 functions as a negative regulator of SA-mediated defense responses to P. syringae. This proposed role is consistent with the recent finding that WRKY25 is a substrate of Arabidopsis MAP kinase 4, a repressor of SA-dependent defense responses.
巻・号 7
ページ 2
公開日 2007-1-10
DOI 10.1186/1471-2229-7-2
PII 1471-2229-7-2
PMID 17214894
PMC PMC1780049
MeSH Amino Acid Sequence Arabidopsis / genetics Arabidopsis / metabolism* Arabidopsis / microbiology* Arabidopsis Proteins / chemistry Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism Arabidopsis Proteins / physiology* Cyclopentanes / pharmacology Ethylenes / pharmacology Gene Expression Regulation, Plant / drug effects Green Fluorescent Proteins / analysis Immunity, Innate / genetics Molecular Sequence Data Oxylipins Plant Growth Regulators / metabolism Plant Growth Regulators / pharmacology Plants, Genetically Modified / metabolism Pseudomonas syringae / physiology* Recombinant Fusion Proteins / analysis Regulatory Sequences, Nucleic Acid Salicylic Acid / metabolism Salicylic Acid / pharmacology Signal Transduction Transcription Factors / chemistry Transcription Factors / genetics Transcription Factors / physiology*
IF 3.497
引用数 135
WOS 分野 PLANT SCIENCES
リソース情報
シロイヌナズナ / 植物培養細胞・遺伝子 pda04973