title: Arabidopsis MAP kinase 4 regulates gene expression through transcription factor release in the nucleus.
abstract: Plant and animal perception of microbes through pathogen surveillance proteins leads to MAP kinase signalling and the expression of defence genes. However, little is known about how plant MAP kinases regulate specific gene expression. We report that, in the absence of pathogens, Arabidopsis MAP kinase 4 (MPK4) exists in nuclear complexes with the WRKY33 transcription factor. This complex depends on the MPK4 substrate MKS1. Challenge with Pseudomonas syringae or flagellin leads to the activation of MPK4 and phosphorylation of MKS1. Subsequently, complexes with MKS1 and WRKY33 are released from MPK4, and WRKY33 targets the promoter of PHYTOALEXIN DEFICIENT3 (PAD3) encoding an enzyme required for the synthesis of antimicrobial camalexin. Hence, wrky33 mutants are impaired in the accumulation of PAD3 mRNA and camalexin production upon infection. That WRKY33 is an effector of MPK4 is further supported by the suppression of PAD3 expression in mpk4-wrky33 double mutant backgrounds. Our data establish direct links between MPK4 and innate immunity and provide an example of how a plant MAP kinase can regulate gene expression by releasing transcription factors in the nucleus upon activation.
authors.affiliation: Department of Biology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Qiu
authors.forename: Berthe Katrine
authors.initials: BK
authors.lastname: Fiil
authors.forename: Klaus
authors.initials: K
authors.lastname: Petersen
authors.forename: Henrik Bjørn
authors.initials: HB
authors.lastname: Nielsen
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Botanga
authors.forename: Stephan
authors.initials: S
authors.lastname: Thorgrimsen
authors.forename: Kristoffer
authors.initials: K
authors.lastname: Palma
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Suarez-Rodriguez
authors.forename: Signe
authors.initials: S
authors.lastname: Sandbech-Clausen
authors.forename: Jacek
authors.initials: J
authors.lastname: Lichota
authors.forename: Peter
authors.initials: P
authors.lastname: Brodersen
authors.forename: Klaus D
authors.initials: KD
authors.lastname: Grasser
authors.forename: Ole
authors.initials: O
authors.lastname: Mattsson
authors.forename: Jane
authors.initials: J
authors.lastname: Glazebrook
authors.forename: John
authors.initials: J
authors.lastname: Mundy
authors.forename: Morten
authors.initials: M
authors.lastname: Petersen
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics* / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D007211:Indoles / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins; D010750:Phosphoproteins / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D044224:Pseudomonas syringae / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020156:Salicylic Acid / Q000494:pharmacology; D013844:Thiazoles / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D000094162:Phytoalexins
chemical_list: D029681:Arabidopsis Proteins; D003577:Cytochrome P-450 Enzyme System; D007211:Indoles; D020928:Mitogen-Activated Protein Kinases; D009687:Nuclear Proteins; D010750:Phosphoproteins; D020156:Salicylic Acid; D013844:Thiazoles; D014157:Transcription Factors; C503586:MKS1 protein, Arabidopsis; C517860:WRKY33 protein, Arabidopsis; C102405:camalexin; D000094162:Phytoalexins; C417307:PAD3 protein, Arabidopsis; C436292:AtMPK4 protein, Arabidopsis