Cytochrome b-c1 complex subunit 2, mitochondrial (UQCRC2)

Cytochrome b-c1 complex subunit 2, mitochondrial (UQCRC2), is a nuclear-encoded core protein of mitochondrial Complex III (ubiquinol-cytochrome c reductase) within the electron transport chain. It is essential for assembly and stabilization of Complex III and proper electron transfer from ubiquinol to cytochrome c, thus driving oxidative phosphorylation and ATP synthesis. UQCRC2 is upregulated or downregulated in certain cancers and its mutations lead to complex III deficiency, manifesting as mitochondrial disease with variable systemic symptoms. The protein plays roles not only in energy metabolism, but regulation of mitophagy under stress via AMPK-NFE2L2/NRF2 pathways, making it a potential biomarker and therapeutic target in specific disease contexts.

Other names

UQCRC2QCR2UQCR2Core protein IIComplex III subunit 2Ubiquinol-cytochrome-c reductase complex core protein 2MC3DN5

Drugs targeting the mitochondrial respiratory chain typically inhibit electron transfer, leading to reduced ATP production and oxidative stress. For experimental agents acting on complex III, the blockade impedes activity of subunits including UQCRC2, but selective molecular inhibition for UQCRC2 is not established.