The F1F0-ATP synthase complex influences the assembly state of the cytochrome bc1-cytochrome oxidase supercomplex and its association with the TIM23 machinery. J Biol Chem 2008 Mar 14;283(11):6677-86
Date
01/12/2008Pubmed ID
18187422DOI
10.1074/jbc.M708440200Abstract
The enzyme complexes involved in mitochondrial oxidative phosphorylation are organized into higher ordered assemblies termed supercomplexes. Subunits e and g (Su e and Su g, respectively) are catalytically nonessential subunits of the F1F0-ATP synthase whose presence is required to directly support the stable dimerization of the ATP synthase complex. We report here that Su g and Su e are also important for securing the correct organizational state of the cytochrome bc1-cytochrome oxidase (COX) supercomplex. Mitochondria isolated from the Delta su e and Delta su g null mutant strains exhibit decreased levels of COX enzyme activity but appear to have normal COX subunit protein levels. An altered stoichiometry of the cytochrome bc1-COX supercomplex was observed in mitochondria deficient in Su e and/or Su g, and a perturbation in the association of Cox4, a catalytically important subunit of the COX complex, was also detected. In addition, an increase in the level of the TIM23 translocase associated with the cytochrome bc1-COX supercomplex is observed in the absence of Su e and Su g. Together, our data highlight that a further level of complexity exists between the oxidative phosphorylation supercomplexes, whereby the organizational state of one complex, i.e. the ATP synthase, may influence that of another supercomplex, namely the cytochrome bc1-COX complex.
Author List
Saddar S, Dienhart MK, Stuart RAAuthor
Rosemary Stuart PhD Professor in the Biology department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
Chromatography, GelDimerization
Electron Transport Complex III
Electron Transport Complex IV
Electrophoresis, Gel, Two-Dimensional
Electrophoresis, Polyacrylamide Gel
Membrane Transport Proteins
Mitochondria
Mitochondrial Proton-Translocating ATPases
Models, Biological
Oxygen
Phosphorylation
Protein Structure, Tertiary
Saccharomyces cerevisiae
Saccharomyces cerevisiae Proteins
