UQCRC2 (ubiquinol-cytochrome c reductase core protein 2) is a core catalytic component of mitochondrial complex III, which catalyzes electron transfer from ubiquinol to cytochrome c while translocating protons across the inner membrane to generate the electrochemical gradient driving ATP synthesis 1. Beyond its canonical role in the electron transport chain, UQCRC2 functions as a critical regulator of mitochondrial quality control and cellular homeostasis. AMPK enhances UQCRC2 expression through NFE2L2/NRF2-mediated transcriptional activation, and elevated UQCRC2 significantly increases mitophagy to attenuate alcohol-induced liver injury 1. UQCRC2 maintains mitochondrial membrane potential and oxidative phosphorylation capacity; knockdown impairs these functions and accelerates cellular senescence in stem cells 2. UQCRC2 expression is downregulated during aging and age-related muscle degeneration; betaine restores UQCRC2 levels and mitigates sarcopenia by suppressing the mitochondrial repressor Mss51 via Yy1 3. In cardioprotection, curcumin upregulates UQCRC2 to improve mitochondrial function and energy homeostasis during ischemia/reperfusion injury 4. UQCRC2 also mediates metabolic reprogramming in tumors; the AMPK/FOXO3a/UQCRC2 axis improves tumor microenvironment oxygenation to suppress metastasis 5. Dysregulation of UQCRC2 is implicated in mitochondrial complex III deficiency and age-related pathologies, suggesting therapeutic potential in metabolic and degenerative diseases.