title: Different patterns in the recognition of editing sites in plant mitochondria.
abstract: Higher plant mitochondrial mRNAs are extensively modified by highly specific C-to-U conversions. However, the determinants of recognition specificity are, to date, unknown. Here, we analyse the cis-elements involved in the recognition of two editing sites in a cox2 gene in wheat mitochondria. A minimal region of 23 nt was found to be involved in recognition of the editing site C77, similar to our previous report for site C259. These regions were correctly recognized by the mitochondrial editing machinery when placed elsewhere in the transcript. The nearest neighbour residues of the target C play a crucial role in editing, but the nature and position of the residue varies according to the editing site concerned. The target region seems to be formed by two regions 5' and 3', which can be separated by a maximum of two residues. Studies on single residue mutants concerning every position in the 23 nt region indicated that editing sites are affected differently by their neighbouring sequences. These results suggest that, notwithstanding the similar extent and location of cis-elements, the editing site recognition mechanisms may differ in plant mitochondria.
authors.affiliation: Laboratoire de Réplication et Expression des Génomes Eucaryotes et Rétroviraux, UMR 5097, Centre National de la Recherche Scientifique and Université Victor Segalen-Bordeaux II 146, rue Leo Saignat 33076 Bordeaux Cedex, France.
authors.forename: David
authors.initials: D
authors.lastname: Choury
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Farré
authors.forename: Xavier
authors.initials: X
authors.lastname: Jordana
authors.forename: Alejandro
authors.initials: A
authors.lastname: Araya
mesh_terms: D003596:Cytosine / Q000378:metabolism; D004252:DNA Mutational Analysis; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D009711:Nucleotides / Q000235:genetics; D012313:RNA / Q000737:chemistry / Q000378:metabolism*; D017393:RNA Editing; D000077278:RNA, Mitochondrial; D018749:RNA, Plant / Q000737:chemistry / Q000378:metabolism*; D014908:Triticum / Q000235:genetics / Q000378:metabolism
chemical_list: D009711:Nucleotides; D000077278:RNA, Mitochondrial; D018749:RNA, Plant; D012313:RNA; D003596:Cytosine; C117108:cytochrome C oxidase subunit II; D003576:Electron Transport Complex IV