Cytochrome c oxidase assembly factor 20 (COA20)

Cytochrome c oxidase assembly factor 20 (COA20), also known as FAM36A, is a mitochondrial inner membrane protein essential for the biogenesis of cytochrome c oxidase (Complex IV), the terminal enzyme of the mitochondrial respiratory chain (UniProt: Q96NI1). It functions as a specialized chaperone that stabilizes the newly synthesized, mitochondrial-encoded COX2 subunit, preventing its premature degradation before incorporation into the maturing complex (Bourens et al., 2014, Hum. Mol. Genet.). COA20 interacts with other factors like COX20 to facilitate the membrane insertion and maturation of COX2 (NCBI Gene: 26125). Deficiencies in COA20 lead to impaired Complex IV assembly, resulting in mitochondrial respiratory chain defects and reduced ATP production. Such defects are associated with severe metabolic disorders, including mitochondrial encephalomyopathy and lactic acidosis (Ozkolaçık et al., 2022, Genes). While not currently a primary target for small-molecule drugs, COA20 is a critical focus for understanding mitochondrial diseases and developing potential gene therapies. Its role is vital for maintaining energy homeostasis in tissues with high metabolic demands, such as the brain and heart.

Other names

FAM36AProtein FAM36AFamily with sequence similarity 36 member A