UQCRH
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 11
MC3DN11
A form of mitochondrial complex III deficiency, a disorder of the mitochondrial respiratory chain resulting in a highly variable phenotype depending on which tissues are affected. MC3DN11 is an autosomal recessive form characterized by recurrent episodes of severe lactic acidosis, hyperammonemia, hypoglycemia, and encephalopathy.
None
The disease may be caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the UQCRH/QCR6 family.
Cellular localization
- Mitochondrion inner membrane
- Peripheral membrane protein
- Intermembrane side
Alternative names
Complex III subunit 6, Complex III subunit VIII, Cytochrome c1 non-heme 11 kDa protein, Mitochondrial hinge protein, Ubiquinol-cytochrome c reductase complex 11 kDa protein, UQCRH