RRC ID 75906
Author Herbert CJ, Labarre-Mariotte S, Cornu D, Sophie C, Panozzo C, Michel T, Dujardin G, Bonnefoy N.
Title Translational activators and mitoribosomal isoforms cooperate to mediate mRNA-specific translation in Schizosaccharomyces pombe mitochondria.
Journal Nucleic Acids Res
Abstract Mitochondrial mRNAs encode key subunits of the oxidative phosphorylation complexes that produce energy for the cell. In Saccharomyces cerevisiae, mitochondrial translation is under the control of translational activators, specific to each mRNA. In Schizosaccharomyces pombe, which more closely resembles the human system by its mitochondrial DNA structure and physiology, most translational activators appear to be either lacking, or recruited for post-translational functions. By combining bioinformatics, genetic and biochemical approaches we identified two interacting factors, Cbp7 and Cbp8, controlling Cytb production in S. pombe. We show that their absence affects cytb mRNA stability and impairs the detection of the Cytb protein. We further identified two classes of Cbp7/Cbp8 partners and showed that they modulated Cytb or Cox1 synthesis. First, two isoforms of bS1m, a protein of the small mitoribosomal subunit, that appear mutually exclusive and confer translational specificity. Second, a complex of four proteins dedicated to Cox1 synthesis, which includes an RNA helicase that interacts with the mitochondrial ribosome. Our results suggest that S. pombe contains, in addition to complexes of translational activators, a heterogeneous population of mitochondrial ribosomes that could specifically modulate translation depending on the mRNA translated, in order to optimally balance the production of different respiratory complex subunits.
Volume 49(19)
Pages 11145-11166
Published 2021-11-8
DOI 10.1093/nar/gkab789
PII 6389634
PMID 34634819
PMC PMC8565316
MeSH Computational Biology / methods Cytochromes b / genetics Cytochromes b / metabolism DNA, Mitochondrial / genetics DNA, Mitochondrial / metabolism Electron Transport Chain Complex Proteins / genetics* Electron Transport Chain Complex Proteins / metabolism Electron Transport Complex IV / genetics Electron Transport Complex IV / metabolism Gene Expression Regulation, Fungal Mitochondria / genetics* Mitochondria / metabolism Oxidative Phosphorylation Protein Biosynthesis* Protein Isoforms / genetics Protein Isoforms / metabolism RNA Stability RNA, Messenger / genetics* RNA, Messenger / metabolism RNA, Mitochondrial / genetics* RNA, Mitochondrial / metabolism Ribosomes / genetics Ribosomes / metabolism Saccharomyces cerevisiae / genetics* Saccharomyces cerevisiae / metabolism Saccharomyces cerevisiae Proteins / genetics Saccharomyces cerevisiae Proteins / metabolism Schizosaccharomyces / genetics* Schizosaccharomyces / metabolism Trans-Activators / genetics Trans-Activators / metabolism
IF 11.502
Yeast pTN-L1