title: AtsPLA2-alpha nuclear relocalization by the Arabidopsis transcription factor AtMYB30 leads to repression of the plant defense response.
abstract: The hypersensitive response (HR), characterized by a rapid and localized cell death at the inoculation site, is one of the most efficient resistance reactions to pathogen attack in plants. The transcription factor AtMYB30 was identified as a positive regulator of the HR and resistance responses during interactions between Arabidopsis and bacteria. Here, we show that AtMYB30 and the secreted phospholipase AtsPLA(2)-alpha physically interact in vivo, following the AtMYB30-mediated specific relocalization of AtsPLA(2)-alpha from cytoplasmic vesicles to the plant cell nucleus. This protein interaction leads to repression of AtMYB30 transcriptional activity and negative regulation of plant HR. Moreover, Atspla(2)-alpha mutant plants are more resistant to bacterial inoculation, whereas AtsPLA(2)-alpha overexpression leads to decreased resistance, confirming that AtsPLA(2)-alpha is a negative regulator of AtMYB30-mediated defense. These data underline the importance of cellular dynamics and, particularly, protein translocation to the nucleus, for defense-associated gene regulation in plants.
authors.affiliation: Laboratoire des Interactions Plantes-Microorganismes, Unité Mixte de Recherche, Centre National de la Recherche Scientifique-Institut National de la Recherche Agronomique 2594/441, F-31320 Castanet-Tolosan, France.
authors.forename: Solène
authors.initials: S
authors.lastname: Froidure
authors.forename: Joanne
authors.initials: J
authors.lastname: Canonne
authors.forename: Xavier
authors.initials: X
authors.lastname: Daniel
authors.forename: Alain
authors.initials: A
authors.lastname: Jauneau
authors.forename: Christian
authors.initials: C
authors.lastname: Brière
authors.forename: Dominique
authors.initials: D
authors.lastname: Roby
authors.forename: Susana
authors.initials: S
authors.lastname: Rivas
mesh_terms: D021581:Active Transport, Cell Nucleus; D017360:Arabidopsis / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D005816:Genetic Complementation Test; D009154:Mutation; D054497:Phospholipases A2, Secretory / Q000235:genetics / Q000378:metabolism*; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D030821:Plants, Genetically Modified; D044224:Pseudomonas syringae / Q000472:pathogenicity; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics / Q000382:microbiology / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D029681:Arabidopsis Proteins; D017931:DNA Primers; C464659:MYB30 protein, Arabidopsis; D018749:RNA, Plant; D014157:Transcription Factors; D054497:Phospholipases A2, Secretory