The MAP kinase substrate MKS1 is a regulator of plant defense responses.
Research output: Contribution to journal › Journal article › Research › peer-review
Arabidopsis MAP kinase 4 (MPK4) functions as a regulator of pathogen defense responses, because it is required for both repression of salicylic acid (SA)-dependent resistance and for activation of jasmonate (JA)-dependent defense gene expression. To understand MPK4 signaling mechanisms, we used yeast two-hybrid screening to identify the MPK4 substrate MKS1. Analyses of transgenic plants and genome-wide transcript profiling indicated that MKS1 is required for full SA-dependent resistance in mpk4 mutants, and that overexpression of MKS1 in wild-type plants is sufficient to activate SA-dependent resistance, but does not interfere with induction of a defense gene by JA. Further yeast two-hybrid screening revealed that MKS1 interacts with the WRKY transcription factors WRKY25 and WRKY33. WRKY25 and WRKY33 were shown to be in vitro substrates of MPK4, and a wrky33 knockout mutant was found to exhibit increased expression of the SA-related defense gene PR1. MKS1 may therefore contribute to MPK4-regulated defense activation by coupling the kinase to specific WRKY transcription factors.
Original language | English |
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Journal | EMBO Journal |
Volume | 24 |
Issue number | 14 |
Pages (from-to) | 2579-89 |
Number of pages | 10 |
ISSN | 0261-4189 |
DOIs | |
Publication status | Published - 2005 |
Bibliographical note
Keywords: Amino Acid Motifs; Amino Acid Sequence; Arabidopsis Proteins; Gene Expression Profiling; Immunity, Natural; Immunohistochemistry; Mitogen-Activated Protein Kinases; Molecular Sequence Data; Phosphoproteins; Phosphorylation; Plants; Saccharomyces cerevisiae; Substrate Specificity; Two-Hybrid System Techniques
ID: 6474536