Fiche publication
Date publication
décembre 2017
Journal
Nucleic acids research
Auteurs
Membres identifiés du Cancéropôle Est :
Mme COGNAT Valérie
Tous les auteurs :
Salinas-Giegé T, Cavaiuolo M, Cognat V, Ubrig E, Remacle C, Duchêne AM, Vallon O, Maréchal-Drouard L
Lien Pubmed
Résumé
The unicellular photosynthetic organism, Chlamydomonas reinhardtii, represents a powerful model to study mitochondrial gene expression. Here, we show that the 5'- and 3'-extremities of the eight Chlamydomonas mitochondrial mRNAs present two unusual characteristics. First, all mRNAs start primarily at the AUG initiation codon of the coding sequence which is often marked by a cluster of small RNAs. Second, unusual tails are added post-transcriptionally at the 3'-extremity of all mRNAs. The nucleotide composition of the tails is distinct from that described in any other systems and can be partitioned between A/U-rich tails, predominantly composed of Adenosine and Uridine, and C-rich tails composed mostly of Cytidine. Based on 3' RACE experiments, 22% of mRNAs present C-rich tails, some of them composed of up to 20 consecutive Cs. Polycytidylation is specific to mitochondria and occurs primarily on mRNAs. This unprecedented post-transcriptional modification seems to be a specific feature of the Chlorophyceae class of green algae and points out the existence of novel strategies in mitochondrial gene expression.
Mots clés
Base Sequence, Chlamydomonas reinhardtii, genetics, Chlorophyta, classification, Genome, Mitochondrial, genetics, Mitochondria, genetics, Phylogeny, Poly C, metabolism, RNA, Messenger, genetics, RNA, Mitochondrial, Sequence Homology, Nucleic Acid, Transcription, Genetic
Référence
Nucleic Acids Res. 2017 Dec 15;45(22):12963-12973
