Genome-wide analysis of mRNAs targeted to yeast mitochondria.
It is agreed that nuclear-encoded mitochondrial proteins are post-translationally targeted to mitochondria, even if, in some cases, a co-translational phase can assist the import of precursor proteins. We used yeast DNA microarrays to analyse the mRNA populations associated with free and mitochondrion-bound polysomes. As expected, many mRNAs, known to encode mitochondrial proteins, are localized to free cytoplasmic polysomes, but many are localized to mitochondrion-bound polysomes. Furthermore, the 3'-UTR of six randomly chosen mitochondrion-bound mRNAs contains sufficient information to target, in vivo, non-translatable RNA to the vicinity of mitochondria. Interestingly, genes producing mRNAs that are targeted to mitochondria are mainly of ancient bacterial origin, whereas those producing mRNAs that are translated in the cytoplasm are mainly of eukaryotic origin. These observations, which support the recent hypotheses concerning the dual origin of the mitochondrial proteome, provide new insights into the biogenesis of mitochondria.
Marc
Philippe
P
Laboratoire de Génétique Moléculaire (UMR CNRS 8541), Ecole Normale Supérieure, 46 rue d'Ulm, F-75005 Paris, France.
Margeot
Antoine
A
Devaux
Frederic
F
Blugeon
Corinne
C
Corral-Debrinski
Marisol
M
Jacq
Claude
C
D004272:DNA, Mitochondrial / Q000235:genetics*; D016681:Genome, Fungal; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000502:physiology
D004272:DNA, Mitochondrial; D012333:RNA, Messenger