title: A stabilizing factor for mitochondrial respiratory supercomplex assembly regulates energy metabolism in muscle.
abstract: The mitochondrial respiratory chain is essential for oxidative phosphorylation and comprises multiple complexes, including cytochrome c oxidase, assembled in macromolecular supercomplexes. Little is known about factors that contribute to supercomplex organization. Here we identify COX7RP as a factor that promotes supercomplex assembly. Cox7rp-knockout mice exhibit decreased muscular activity and heat production failure in the cold due to reduced COX activity. In contrast, COX7RP-transgenic mice exhibit increased exercise performance with increased cytochrome c oxidase activity. Two-dimensional blue native electrophoresis reveals that COX7RP is a key molecule that promotes assembly of the III2/IVn supercomplex with complex I. Our study identified COX7RP as a protein that functions in I/III2/IVn supercomplex assembly and is required for full activity of mitochondrial respiration.
authors.affiliation: Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, 1397-1 Yamane, Hidaka-shi, Saitama, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ikeda
authors.forename: Sachiko
authors.initials: S
authors.lastname: Shiba
authors.forename: Kuniko
authors.initials: K
authors.lastname: Horie-Inoue
authors.forename: Kunitoshi
authors.initials: K
authors.lastname: Shimokata
authors.forename: Satoshi
authors.initials: S
authors.lastname: Inoue
mesh_terms: D000818:Animals; D001833:Body Temperature Regulation; D042967:Electron Transport Complex I / Q000235:genetics / Q000378:metabolism*; D014450:Electron Transport Complex III / Q000235:genetics / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D008931:Mitochondria, Muscle / Q000201:enzymology* / Q000235:genetics; D018482:Muscle, Skeletal / Q000201:enzymology*; D010085:Oxidative Phosphorylation
chemical_list: C585960:Cox7a2l protein, mouse; D003576:Electron Transport Complex IV; D042967:Electron Transport Complex I; D014450:Electron Transport Complex III