Cytochrome c oxidase subunit 7C, mitochondrial

COX7C is a small structural component of cytochrome c oxidase (Complex IV), the terminal enzyme of the mitochondrial electron transport chain (UniProt: P15954). It participates in the transfer of electrons from cytochrome c to molecular oxygen, a critical step in oxidative phosphorylation that generates the proton gradient driving ATP synthesis.

COX7C is a mitochondrial matrix protein and integral part of respiratory chain function. No primary disease associations are documented in UniProt curated records; however, given its role in energy metabolism, mitochondrial dysfunction is a relevant biological context.

COX7C is downregulated in Alzheimer's Disease brain tissue. According to post-mortem AD proteomics analysis (Chaparral AD proteomics), COX7C expression is reduced relative to age-matched controls with a mean log2 fold-change of −0.685 across subcellular fractions. This downregulation may reflect compromised mitochondrial oxidative capacity and energy deficit, consistent with known metabolic dysfunction in AD pathophysiology.