title: The peripheral stalk participates in the yeast ATP synthase dimerization independently of e and g subunits.
abstract: It is now clearly established that dimerization of the F(1)F(o) ATP synthase takes place in the mitochondrial inner membrane. Interestingly, oligomerization of this enzyme seems to be involved in cristae morphogenesis. As they were able to form homodimers, subunits 4, e, and g have been proposed as potential ATP synthase dimerization subunits. In this paper, we provide evidence that subunit h, a peripheral stalk component, is located either at or near the ATP synthase dimerization interface. Subunit h homodimers were formed in mitochondria and were found to be associated to ATP synthase dimers. Moreover, homodimerization of subunit h and of subunit i turned out to be independent of subunits e and g, confirming the existence of an ATP synthase dimer in the mitochondrial inner membrane in the absence of subunits e and g. For the first time, this dimer has been observed by BN-PAGE. Finally, from these results we are now able to update our model for the supramolecular organization of the ATP synthase in the membrane and propose a role for subunits e and g, which stabilize the ATP synthase dimers and are involved in the oligomerization of the complex.
authors.affiliation: Institut de Biochimie et Génétique Cellulaires du Centre National de la Recherche Scientifique, UMR5095, Université Victor Segalen Bordeaux 2, 1 rue Camille Saint-Saëns, 33077 Bordeaux Cedex, France.
authors.forename: Rémi
authors.initials: R
authors.lastname: Fronzes
authors.forename: Théodore
authors.initials: T
authors.lastname: Weimann
authors.forename: Jacques
authors.initials: J
authors.lastname: Vaillier
authors.forename: Jean
authors.initials: J
authors.lastname: Velours
authors.forename: Daniel
authors.initials: D
authors.lastname: Brèthes
mesh_terms: D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D025261:Mitochondrial Proton-Translocating ATPases / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
chemical_list: C474451:F1F0-ATP synthase; D025261:Mitochondrial Proton-Translocating ATPases