Cytochrome c oxidase subunit 7A1, mitochondrial

COX7A1 is a 79-amino acid mitochondrial protein that functions as a component of cytochrome c oxidase complex IV (CIV), the terminal enzyme of the electron transport chain responsible for reducing oxygen to water during oxidative phosphorylation (UniProt: P24310). The protein also acts as an assembly factor that promotes homodimerization of CIV complexes to form respirasomes, mitochondrial respiratory supercomplexes with enhanced catalytic activity (UniProt: P24310).

COX7A1 is expressed widely across tissues, with notably high levels in brown adipose tissue, though it is not required for thermogenesis (UniProt: P24310). No disease associations are documented in UniProt curated records.

COX7A1 is associated with Alzheimer's Disease through proteomic analysis (Chaparral AD proteomics). The protein is significantly downregulated in post-mortem AD brain tissue compared to age-matched controls, with a mean log2 fold-change of −0.65 across one subcellular fraction examined in TMT-labeled proteomics data (Chaparral AD proteomics). This downregulation suggests compromised mitochondrial oxidative capacity in AD pathology.