title: Mediated plastid RNA editing in plant immunity.
abstract: Plant regulatory circuits coordinating nuclear and plastid gene expression have evolved in response to external stimuli. RNA editing is one of such control mechanisms. We determined the Arabidopsis nuclear-encoded homeodomain-containing protein OCP3 is incorporated into the chloroplast, and contributes to control over the extent of ndhB transcript editing. ndhB encodes the B subunit of the chloroplast NADH dehydrogenase-like complex (NDH) involved in cyclic electron flow (CEF) around photosystem I. In ocp3 mutant strains, ndhB editing efficiency decays, CEF is impaired and disease resistance to fungal pathogens substantially enhanced, a process recapitulated in plants defective in editing plastid RNAs encoding NDH complex subunits due to mutations in previously described nuclear-encoded pentatricopeptide-related proteins (i.e. CRR21, CRR2). Furthermore, we observed that following a pathogenic challenge, wild type plants respond with editing inhibition of ndhB transcript. In parallel, rapid destabilization of the plastidial NDH complex is also observed in the plant following perception of a pathogenic cue. Therefore, NDH complex activity and plant immunity appear as interlinked processes.
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Ciudad Politécnica de la Innovación, Ingeniero Fausto Elio, Valencia, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: García-Andrade
authors.forename: Vicente
authors.initials: V
authors.lastname: Ramírez
authors.forename: Ana
authors.initials: A
authors.lastname: López
authors.forename: Pablo
authors.initials: P
authors.lastname: Vera
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D018398:Homeodomain Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D009154:Mutation; D009245:NADH Dehydrogenase / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D057865:Plant Immunity / Q000502:physiology*; D018087:Plastids / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D017393:RNA Editing / Q000502:physiology*; D020871:RNA Stability / Q000502:physiology*; D018749:RNA, Plant / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; C507065:OCP3 protein, Arabidopsis; D018749:RNA, Plant; D014157:Transcription Factors; C079008:ndhB protein, Arabidopsis; D009245:NADH Dehydrogenase