title: Two interacting proteins are necessary for the editing of the NdhD-1 site in Arabidopsis plastids.
abstract: After transcription, mRNA editing in angiosperm chloroplasts and mitochondria results in the conversion of cytidine to uridine by deamination. Analysis of Arabidopsis thaliana mutants affected in RNA editing have shown that many pentatricopeptide repeat proteins (PPRs) are required for specific cytidine deamination events. PPR proteins have been shown to be sequence-specific RNA binding proteins allowing the recognition of the C to be edited. The C-terminal DYW domain present in many editing factors has been proposed to catalyze C deamination, as it shows sequence similarities with cytidine deaminases in other organisms. However, many editing factors, such as the first to be discovered, CHLORORESPIRATORY REDUCTION4 (CRR4), lack this domain, so its importance has been unclear. Using a reverse genetic approach, we identified DYW1, an RNA editing factor acting specifically on the plastid ndhD-1 editing site recognized by CRR4. Unlike other known editing factors, DYW1 contains no identifiable PPR motifs but does contain a clear DYW domain. We were able to show interaction between CRR4 and DYW1 by bimolecular fluorescence complementation and to reconstitute a functional chimeric CRR4-DYW1 protein complementing the crr4 dyw1double mutant. We propose that CRR4 and DYW1 act together to edit the ndhD-1 site.
authors.affiliation: Unité de Recherche en Génomique Végétale, Unité Mixte de Recherche, Institut National de la Recherche Agronomique/Université Evry Val d'Essone/Equipe de Recherche Labellisée, Centre National de la Recherche Scientifique 91057, 91057 Evry cedex, France.
authors.forename: Clément
authors.initials: C
authors.lastname: Boussardon
authors.forename: Véronique
authors.initials: V
authors.lastname: Salone
authors.forename: Alexandra
authors.initials: A
authors.lastname: Avon
authors.forename: Richard
authors.initials: R
authors.lastname: Berthomé
authors.forename: Kamel
authors.initials: K
authors.lastname: Hammani
authors.forename: Kenji
authors.initials: K
authors.lastname: Okuda
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Shikanai
authors.forename: Ian
authors.initials: I
authors.lastname: Small
authors.forename: Claire
authors.initials: C
authors.lastname: Lurin
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D055786:Gene Knockout Techniques; D008969:Molecular Sequence Data; D009154:Mutation; D018087:Plastids / Q000378:metabolism; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D017393:RNA Editing / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D029681:Arabidopsis Proteins; C583236:CRR4 protein, Arabidopsis; D002352:Carrier Proteins; C583235:DYW1 protein, Arabidopsis; D018749:RNA, Plant; D016601:RNA-Binding Proteins; C538752:pentatricopeptide repeat protein, Arabidopsis