Entrez 10975 | Ensembl ENSG00000127540 | |
Aliases UQCR11, 0710008D09Rik, QCR10, UQCR, ubiquinol-cytochrome c reductase, complex III subunit XI External IDs MGI: 1913844 HomoloGene: 4974 GeneCards: UQCR11 | ||
UQCR11 (ubiquinol-cytochrome c reductase, complex III subunit XI) is a protein that in humans is encoded by the UQCR11 gene. UQCR11 is the smallest known component of Complex III in the mitochondrial respiratory chain.
Contents
Structure
The UQCR11 gene, located on the p arm of chromosome 19 in position 13.3, is made up of 3 exons and is 8,329 base pairs in length. The UQCR11 protein weighs 6.6 kDa and is composed of 56 amino acids. This gene encodes the smallest known component of the ubiquinol-cytochrome c reductase complex, which is also known as Complex III and is part of the mitochondrial respiratory chain. In vertebrates, Complex III contains 11 subunits: 3 respiratory subunits, 2 core proteins and 6 low-molecular weight proteins. Proteobacterial complexes may contain as few as three subunits.
Function
The UQCR11 protein may function as a binding factor for the iron-sulfur protein in Complex III, which is ubiquitous in human cells. Complex III catalyzes the chemical reaction
QH2 + 2 ferricytochrome cThus, the two substrates of Complex III are dihydroquinone (QH2) and ferri- (Fe3+) cytochrome c, whereas its 3 products are quinone (Q), ferro- (Fe2+) cytochrome c, and H+. This complex belongs to the family of oxidoreductases, specifically those acting on diphenols and related substances as donor with a cytochrome as acceptor. This enzyme participates in oxidative phosphorylation. It has four cofactors: cytochrome c1, cytochrome b-562, cytochrome b-566 and a 2-Iron ferredoxin of the Rieske type.