title: The cytidine deaminase signature HxE(x)n CxxC of DYW1 binds zinc and is necessary for RNA editing of ndhD-1.
abstract: In flowering plants, RNA editing involves deamination of specific cytidines to uridines in both mitochondrial and chloroplast transcripts. Pentatricopeptide repeat (PPR) proteins and multiple organellar RNA editing factor (MORF) proteins have been shown to be involved in RNA editing but none have been shown to possess cytidine deaminase activity. The DYW domain of some PPR proteins contains a highly conserved signature resembling the zinc-binding active site motif of known nucleotide deaminases. We modified these highly conserved amino acids in the DYW motif of DYW1, an editing factor required for editing of the ndhD-1 site in Arabidopsis chloroplasts. We demonstrate that several amino acids of this signature motif are required for RNA editing in vivo and for zinc binding in vitro. We conclude that the DYW domain of DYW1 has features in common with cytidine deaminases, reinforcing the hypothesis that this domain forms part of the active enzyme that carries out RNA editing in plants.
authors.affiliation: Unité de Recherche en Génomique Végétale (URGV), UMR INRA/UEVE - ERL CNRS, SPS Labex, CP 5708, 91057, Evry Cedex, France.|Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, 6009, Australia.
authors.forename: Clément
authors.initials: C
authors.lastname: Boussardon
authors.affiliation: Unité de Recherche en Génomique Végétale (URGV), UMR INRA/UEVE - ERL CNRS, SPS Labex, CP 5708, 91057, Evry Cedex, France.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Avon
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, 6009, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Kindgren
authors.affiliation: School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA, 6009, Australia.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Bond
authors.affiliation: School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA, 6009, Australia.
authors.forename: Michael
authors.initials: M
authors.lastname: Challenor
authors.affiliation: Unité de Recherche en Génomique Végétale (URGV), UMR INRA/UEVE - ERL CNRS, SPS Labex, CP 5708, 91057, Evry Cedex, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Lurin
authors.affiliation: Australian Research Council Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA, 6009, Australia.
authors.forename: Ian
authors.initials: I
authors.lastname: Small
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism*; D003564:Cytidine Deaminase / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017393:RNA Editing / Q000235:genetics*; D016415:Sequence Alignment; D013054:Spectrophotometry, Atomic; D040681:Structural Homology, Protein; D013329:Structure-Activity Relationship; D014364:Tryptophan / Q000378:metabolism; D015032:Zinc / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; C583235:DYW1 protein, Arabidopsis; D014364:Tryptophan; D003564:Cytidine Deaminase; D015032:Zinc
keywords: DYW domain; RNA editing; cytidine deaminase; pentatricopeptide repeat (PPR) proteins; zinc-binding motif