title: Mitochondrial protein synthesis: efficiency and accuracy.
abstract: CONCLUSIONS
  The mitochondrial genetic system is responsible for the production of a few core-subunits of the respiratory chain and ATP synthase, the membrane protein complexes driving oxidative phosphorylation (OXPHOS). Efficiency and accuracy of mitochondrial protein synthesis determines how efficiently new OXPHOS complexes can be made.
  
  
  BACKGROUND
  The system responsible for expression of the mitochondrial-encoded subunits developed from that of the bacterial ancestor of mitochondria. Importantly, many aspects of genome organization, transcription, and translation have diverged during evolution. Recent research has provided new insights into the architecture, regulation, and organelle-specific features of mitochondrial translation. Mitochondrial ribosomes contain a number of proteins absent from prokaryotic ribosomes, implying that in mitochondria, ribosomes were tailored to fit the requirements of the organelle. In addition, mitochondrial gene expression is regulated post-transcriptionally by a number of mRNA-specific translational activators. At least in yeast, these factors can regulate translation in respect to OXPHOS complex assembly to adjust the level of newly synthesized proteins to amounts that can be successfully assembled into respiratory chain complexes.
  
  
  RESULTS
  Mitochondrial gene expression is determining aging in eukaryotes, and a number of recent reports indicate that efficiency of translation directly influences this process.
  
  
  CONCLUSIONS
  Here we will summarize recent advances in our understanding of mitochondrial protein synthesis by comparing the knowledge acquired in the systems most commonly used to study mitochondrial biogenesis. However, many steps have not been understood mechanistically. Innovative biochemical and genetic approaches have to be elaborated to shed light on these important processes.
authors.affiliation: 1 Center for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University , Stockholm, Sweden .
authors.forename: Kirsten
authors.initials: K
authors.lastname: Kehrein
authors.forename: Nathalie
authors.initials: N
authors.lastname: Bonnefoy
authors.forename: Martin
authors.initials: M
authors.lastname: Ott
mesh_terms: D000818:Animals; D006801:Humans; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000096:biosynthesis*; D010085:Oxidative Phosphorylation
chemical_list: D024101:Mitochondrial Proteins