title: Mitochondrial F1Fo-ATP synthase: the small subunits e and g associate with monomeric complexes to trigger dimerization.
abstract: Mitochondrial F(1)F(o)-ATP synthase catalyzes the formation of ATP from ADP and inorganic phosphate. The enzyme is found in monomeric, dimeric and higher oligomeric forms in the inner mitochondrial membrane. Dimerization of ATP synthase complexes is a prerequisite for the generation of larger oligomers that promote membrane bending and formation of tubular cristae membranes. Two small proteins of the membrane-embedded F(o)-domain, subunit e (Su e; Atp21) and Su g (Atp20), were identified as dimer-specific subunits of yeast ATP synthase and shown to be required for stabilization of the dimers. We have identified two distinct monomeric forms of yeast ATP synthase. Su e and Su g are present not only in the dimer but also in one of the monomeric forms. We demonstrate that Su e and Su g sequentially assemble with monomeric ATP synthase to form a dimerization-competent primed monomer. We conclude that association of Su e and Su g with monomeric F(1)F(o)-ATP synthase represents an initial step of oligomer formation.
authors.affiliation: Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany.
authors.forename: Karina
authors.initials: K
authors.lastname: Wagner
authors.forename: Peter
authors.initials: P
authors.lastname: Rehling
authors.forename: Luiza K
authors.initials: LK
authors.lastname: Sanjuán Szklarz
authors.forename: Rebecca D
authors.initials: RD
authors.lastname: Taylor
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Pfanner
authors.forename: Martin
authors.initials: M
authors.lastname: van der Laan
mesh_terms: D019281:Dimerization; D025261:Mitochondrial Proton-Translocating ATPases / Q000378:metabolism*; D011485:Protein Binding; D055503:Protein Multimerization / Q000502:physiology; D021122:Protein Subunits / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013997:Time Factors
chemical_list: C503883:ATP20 protein, S cerevisiae; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; D025261:Mitochondrial Proton-Translocating ATPases; C102550:TIM11 protein, S cerevisiae; D006180:Proton-Translocating ATPases