SCO2 cytochrome c oxidase assembly protein (SCO2)

SCO2 cytochrome c oxidase assembly protein (SCO2) is a mitochondrial metallochaperone essential for the assembly of cytochrome c oxidase (Complex IV) in the mitochondrial respiratory chain[1][2]. It specifically mediates delivery of copper ions to the CuA site of cytochrome c oxidase subunit II, working alongside SCO1 and interacting with additional assembly factors[1][2][3]. SCO2 also acts as a thiol-disulfide oxidoreductase during later stages of assembly, thereby regulating cysteine residues and facilitating correct maturation and enzymatic activity of Complex IV[1][2]. Dysfunction (largely due to mutations) in SCO2 impairs mitochondrial respiration, leading to tissue-specific deficiencies in oxidative phosphorylation, which manifest clinically as severe neuromuscular, cardiac, or ocular syndromes[1][2]. Recent evidence supports roles for SCO2 in metabolic regulation and as a possible cancer biomarker, owing to its linkage with p53-regulated metabolic switching and prognostic significance in multiple tumor types[2].

Other names

SCO2 homolog, mitochondrialSCO cytochrome oxidase deficient homolog 2CEMCOX1MYP6SCO1L

Supplementation with copper rescues cytochrome c oxidase function in cells with SCO2 mutations[2] Potential future targeting: enhancement of copper delivery, or modulation of redox-regulating chaperone activity[2]