SCO2 is one of the COX assembly factors. SCO2 protein is a metallochaperone that is involved in the biogenesis of cytochrome c oxidase subunit II. SCO2 is a mitochondrial inner membrane-associated metallochaperone required for cytochrome c oxidase (complex IV) biogenesis by delivering copper to the COX2 subunit and supporting assembly of the respiratory chain. Through its role in oxidative phosphorylation, SCO2 helps maintain mitochondrial membrane potential, ATP production, and redox homeostasis, linking it to cellular energy metabolism and stress responses. Disruption of SCO2 impairs complex IV activity and can shift cells toward altered metabolic states, impacting processes such as reactive oxygen species handling and apoptosis sensitivity.