Ubiquinol-cytochrome c reductase complex III subunit XI (UQCR11)

Ubiquinol-cytochrome c reductase complex III subunit XI (UQCR11) is the smallest known subunit (approximately 6.6 kDa) of mitochondrial Complex III (the cytochrome bc1 complex), a key enzyme complex in the electron transport chain responsible for oxidative phosphorylation and energy production in human cells. UQCR11 may assist as a binding factor for the iron-sulfur protein required for electron transfer, supporting both assembly and stability of Complex III. Mutations in UQCR11 have been associated with combined oxidative phosphorylation deficiencies and mitochondrial disease. While not a direct drug target, alteration or inhibition of Complex III (e.g., via antimycin A or related compounds) involves the entire complex, including UQCR11, with effects on cellular energy generation and oxygen utilization. UQCR11 is ubiquitously expressed but is especially critical for tissues with high energy demands due to its role in mitochondrial respiration.

Other names

UQCR11QCR10UQCRComplex III subunit 10Complex III subunit XIUbiquinol-cytochrome c reductase complex 6.4 kDa protein0710008D09RikLOC686951Cytochrome b-c1 complex subunit 10

Inhibition of electron transfer in Complex III (for drugs such as antimycin A acting on the cytochrome bc1 complex). Disruption of oxidative phosphorylation and ATP production, leading to cell death in susceptible cells.