title: Proteomics unravels the exportability of mitochondrial respiratory chains.
abstract: Expression of F1Fo-ATP synthase, which generates the majority of cellular ATP and is believed to be strictly confined to mitochondria, has recently been identified in ectopic locations, together with the four complexes of oxidative phosphorylation (OXPHOS) or enzymes from the Krebs cycle. Identification of these proteins has mostly been accomplished by proteomic methods and mass spectrometry - techniques that hold great promise in increasing our understanding of the proteome. The ectopic presence of ATP synthase has variably been attributed to contamination of the sample or to its action as a cell-surface receptor for apparently unrelated ligands, but OXPHOS proteins have sometimes been found to be catalytically active in oxidative phosphorylation, as they were true components of the system under investigation. The present article focuses on how mass spectrometry can increase our understanding of the proteome of subcellular membranes. We review the recent evidence for an extra-mitochondrial expression of OXPHOS by proteomics studies, highlighting what we can learn by combining these data.
authors.affiliation: Department of Biology, University of Genoa, Viale Bendetto XV, 5, 16132 Genova, Italy.
authors.forename: Isabella
authors.initials: I
authors.lastname: Panfoli
authors.forename: Silvia
authors.initials: S
authors.lastname: Ravera
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bruschi
authors.forename: Giovanni
authors.initials: G
authors.lastname: Candiano
authors.forename: Alessandro
authors.initials: A
authors.lastname: Morelli
mesh_terms: D000818:Animals; D002952:Citric Acid Cycle / Q000235:genetics / Q000502:physiology; D004579:Electron Transport / Q000235:genetics / Q000502:physiology*; D006801:Humans; D024101:Mitochondrial Proteins / Q000378:metabolism*; D010085:Oxidative Phosphorylation; D040901:Proteomics / Q000379:methods*
chemical_list: D024101:Mitochondrial Proteins