Bovine coupling factor 6, with just 14.5% shared identity, replaces subunit h in the yeast ATP synthase.
The mammalian mitochondrial ATP synthase is composed of at least 16 polypeptides. With the exception of coupling factor F(6), there are likely yeast homologs for each of these polypeptides. There are no obvious yeast homologs of F(6), as predicted from primary sequence comparison of the putative peptides encoded by the open reading frames in the yeast genome. In this manuscript, we demonstrate that expression of bovine F(6) complements a null mutant in ATP14 gene in yeast Saccharomyces cerevisiae. Subunit h of the yeast ATP synthase is encoded by ATP14 and is just 14.5% identical to bovine F(6). Expression of bovine F(6) in an atp14 null mutant strain recovers oxidative phosphorylation, and the ATP synthase is active, although functioning with a lower efficiency than the wild type enzyme. Like subunit h, bovine F(6) is shown to interact mainly with subunit 4 (subunit b), a component of the second stalk of the enzyme. These data indicated the subunit h is the yeast homolog of mammalian coupling factor F(6).
Velours
J
J
Institut de Biochimie et Génétique Cellulaires du CNRS, Université Victor Ségalen, Bordeaux 2, 1 rue Camille Saint Saëns, 33077 Bordeaux, cedex France. jean.velours@ibgc.u-bordeaux2.fr
Vaillier
J
J
Paumard
P
P
Soubannier
V
V
Lai-Zhang
J
J
Mueller
D M
DM
D000251:Adenosine Triphosphatases / Q000737:chemistry*; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D025261:Mitochondrial Proton-Translocating ATPases; D008969:Molecular Sequence Data; D010086:Oxidative Phosphorylation Coupling Factors; D021122:Protein Subunits; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins
D010086:Oxidative Phosphorylation Coupling Factors; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; C101128:ATP14 protein, S cerevisiae; D000251:Adenosine Triphosphatases; C000628217:F(6) ATPase; D025261:Mitochondrial Proton-Translocating ATPases; D006180:Proton-Translocating ATPases