Published on Sept. 4, 2007 in FEBS Lett volume 581.
PubMed ID: 17706197
We report here the characterization of the yeast mto2 null mutants carrying wild-type mitochondrial DNA or 15S rRNA C1049G allele. The amounts of mitochondrial tRNA(Lys), tRNA(Glu), tRNA(Gln), tRNA(Leu), tRNA(Gly) and tRNA(Met) were markedly decreased but those of tRNA(Arg) and tRNA(His) were not affected in mto2 strains. The mto2 strains exhibited significant reduction in the aminoacylation of tRNA(Lys), tRNA(Leu) but almost no effect in those of tRNA(His). Interestingly, the strain carrying the C1049G allele exhibited an impairment of aminoacylation of those tRNAs. Furthermore, the steady-state levels of mitochondrial mRNA CYTB, COX1, COX2, COX3, and ATP6 were markedly decreased in mto2 strains. These data strongly indicate that unmodified tRNA caused by the deletion of MTO2 caused the instability of mitochondrial tRNAs and mRNAs and impairment of aminoacylation of tRNAs.