Large gene overlaps and tRNA processing in the compact mitochondrial genome of the crustacean Armadillidium vulgare.
Fiche publication
Date publication
janvier 2015
Journal
RNA biology
Auteurs
Membres identifiés du Cancéropôle Est :
Dr MARÉCHAL-DROUARD Laurence, Mr ALIOUA Abdelmalek
Tous les auteurs :
Doublet V, Ubrig E, Alioua A, Bouchon D, Marcadé I, Maréchal-Drouard L
Lien Pubmed
Résumé
A faithful expression of the mitochondrial DNA is crucial for cell survival. Animal mitochondrial DNA (mtDNA) presents a highly compact gene organization. The typical 16.5 kbp animal mtDNA encodes 13 proteins, 2 rRNAs and 22 tRNAs. In the backyard pillbug Armadillidium vulgare, the rather small 13.9 kbp mtDNA encodes the same set of proteins and rRNAs as compared to animal kingdom mtDNA, but seems to harbor an incomplete set of tRNA genes. Here, we first confirm the expression of 13 tRNA genes in this mtDNA. Then we show the extensive repair of a truncated tRNA, the expression of tRNA involved in large gene overlaps and of tRNA genes partially or fully integrated within protein-coding genes in either direct or opposite orientation. Under selective pressure, overlaps between genes have been likely favored for strong genome size reduction. Our study underlines the existence of unknown biochemical mechanisms for the complete gene expression of A. vulgare mtDNA, and of co-evolutionary processes to keep overlapping genes functional in a compacted mitochondrial genome.
Mots clés
Animals, Crustacea, genetics, DNA, Mitochondrial, genetics, Gene Expression Regulation, Genome, Mitochondrial, RNA, Transfer, genetics
Référence
RNA Biol. 2015 ;12(10):1159-68