title: Repressor- and activator-type ethylene response factors functioning in jasmonate signaling and disease resistance identified via a genome-wide screen of Arabidopsis transcription factor gene expression.
abstract: To identify transcription factors (TFs) involved in jasmonate (JA) signaling and plant defense, we screened 1,534 Arabidopsis (Arabidopsis thaliana) TFs by real-time quantitative reverse transcription-PCR for their altered transcript at 6 h following either methyl JA treatment or inoculation with the incompatible pathogen Alternaria brassicicola. We identified 134 TFs that showed a significant change in expression, including many APETALA2/ethylene response factor (AP2/ERF), MYB, WRKY, and NAC TF genes with unknown functions. Twenty TF genes were induced by both the pathogen and methyl JA and these included 10 members of the AP2/ERF TF family, primarily from the B1a and B3 subclusters. Functional analysis of the B1a TF AtERF4 revealed that AtERF4 acts as a novel negative regulator of JA-responsive defense gene expression and resistance to the necrotrophic fungal pathogen Fusarium oxysporum and antagonizes JA inhibition of root elongation. In contrast, functional analysis of the B3 TF AtERF2 showed that AtERF2 is a positive regulator of JA-responsive defense genes and resistance to F. oxysporum and enhances JA inhibition of root elongation. Our results suggest that plants coordinately express multiple repressor- and activator-type AP2/ERFs during pathogen challenge to modulate defense gene expression and disease resistance.
authors.affiliation: Cooperative Research Centre for Tropical Plant Protection, University of Queensland, St. Lucia, Australia.
authors.forename: Ken C
authors.initials: KC
authors.lastname: McGrath
authors.forename: Bruno
authors.initials: B
authors.lastname: Dombrecht
authors.forename: John M
authors.initials: JM
authors.lastname: Manners
authors.forename: Peer M
authors.initials: PM
authors.lastname: Schenk
authors.forename: Cameron I
authors.initials: CI
authors.lastname: Edgar
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Maclean
authors.forename: Wolf-Rüdiger
authors.initials: WR
authors.lastname: Scheible
authors.forename: Michael K
authors.initials: MK
authors.lastname: Udvardi
authors.forename: Kemal
authors.initials: K
authors.lastname: Kazan
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D003517:Cyclopentanes / Q000378:metabolism*; D005030:Ethylenes / Q000378:metabolism*; D015870:Gene Expression; D017343:Genes, Plant; D018745:Genome, Plant; D054883:Oxylipins; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D003517:Cyclopentanes; D005030:Ethylenes; D054883:Oxylipins; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C011006:jasmonic acid; C036216:ethylene