title: Oxa1p, which is required for cytochrome c oxidase and ATP synthase complex formation, is embedded in the mitochondrial inner membrane.
abstract: We have previously isolated the yeast nuclear gene OXA1 and showed that Oxa1p is required for the formation of the cytochrome c oxidase and ATP synthase complexes. We have expressed Oxa1p in E. coli and shown that it is toxic and rapidly degraded. Nevertheless, a truncated protein was successfully expressed and antibodies have been raised against this truncated protein. These antibodies recognise a protein in mitochondrially enriched fractions. In vitro mitochondrial import experiments demonstrate that the import of Oxa1p is accompanied by the cleavage of a long pre-sequence. Osmotic swelling and alkaline carbonate extraction show that Oxa1p is an integral membrane protein located in the inner membrane of mitochondria. The relationships between the sub-mitochondrial location and the function of Oxa1p are discussed.
authors.affiliation: Centre de Génétique Moléculaire du CNRS, Avenue de la Terrasse, F-91198 Gif sur Yvette, France.
authors.forename: M
authors.initials: M
authors.lastname: Kermorgant
authors.forename: N
authors.initials: N
authors.lastname: Bonnefoy
authors.forename: G
authors.initials: G
authors.lastname: Dujardin
mesh_terms: D000818:Animals; D001692:Biological Transport; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000276:immunology; D008928:Mitochondria / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure*; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; C090858:OXA1 protein; D011993:Recombinant Fusion Proteins; D003576:Electron Transport Complex IV; D006180:Proton-Translocating ATPases