UQCRB
Function
Component of the ubiquinol-cytochrome c oxidoreductase, a multisubunit transmembrane complex that is part of the mitochondrial electron transport chain which drives oxidative phosphorylation. The respiratory chain contains 3 multisubunit complexes succinate dehydrogenase (complex II, CII), ubiquinol-cytochrome c oxidoreductase (cytochrome b-c1 complex, complex III, CIII) and cytochrome c oxidase (complex IV, CIV), that cooperate to transfer electrons derived from NADH and succinate to molecular oxygen, creating an electrochemical gradient over the inner membrane that drives transmembrane transport and the ATP synthase. The cytochrome b-c1 complex catalyzes electron transfer from ubiquinol to cytochrome c, linking this redox reaction to translocation of protons across the mitochondrial inner membrane, with protons being carried across the membrane as hydrogens on the quinol. In the process called Q cycle, 2 protons are consumed from the matrix, 4 protons are released into the intermembrane space and 2 electrons are passed to cytochrome c.
Involvement in disease
Mitochondrial complex III deficiency, nuclear type 3
MC3DN3
A disorder of the mitochondrial respiratory chain resulting in a highly variable phenotype depending on which tissues are affected. Clinical features include mitochondrial encephalopathy, psychomotor retardation, ataxia, severe failure to thrive, liver dysfunction, renal tubulopathy, muscle weakness and exercise intolerance.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the UQCRB/QCR7 family.
Cellular localization
- Mitochondrion inner membrane
- Peripheral membrane protein
- Matrix side
Alternative names
UQBP, UQCRB, Cytochrome b-c1 complex subunit 7, Complex III subunit 7, Complex III subunit VII, QP-C, Ubiquinol-cytochrome c reductase complex 14 kDa protein