Schizosaccharomyces pombe homologs of the Saccharomyces cerevisiae mitochondrial proteins Cbp6 and Mss51 function at a post-translational step of respiratory complex biogenesis.

Centre de Génétique Moléculaire du CNRS, UPR 3404, FRC3115, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France.
Mitochondrion (Impact Factor: 4.03). 02/2012; 12(3):381-90. DOI: 10.1016/j.mito.2012.02.002
Source: PubMed

ABSTRACT Complexes III and IV of the mitochondrial respiratory chain contain a few key subunits encoded by the mitochondrial genome. In Saccharomyces cerevisiae, fifteen mRNA-specific translational activators control mitochondrial translation, of which five are conserved in Schizosaccharomyces pombe. These include homologs of Cbp3, Cbp6 and Mss51 that participate in translation and the post-translational steps leading to the assembly of respiratory complexes III and IV. In this study we show that in contrast to budding yeast, Cbp3, Cbp6 and Mss51 from S. pombe are not required for the translation of mitochondrial mRNAs, but fulfill post-translational functions, thus probably accounting for their conservation.

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