Coenzyme Q biosynthesis protein 4 homolog, mitochondrial (COQ4)

Coenzyme Q biosynthesis protein 4 homolog, mitochondrial (COQ4) is a non-enzymatic scaffold protein essential for the biosynthesis of coenzyme Q (ubiquinone) in the mitochondrial inner membrane. COQ4 organizes and stabilizes the multi-protein complex responsible for coenzyme Q production, indirectly supporting mitochondrial oxidative phosphorylation, cellular energy generation, and antioxidant protection. Mutations in COQ4 cause primary coenzyme Q10 deficiency, a rare mitochondrial disease that can result in neurological, muscular, and renal symptoms due to impaired energy metabolism and increased vulnerability to oxidative stress. COQ4 is a therapeutic target in the sense that its dysfunction leads to disease states treatable by ubiquinone supplementation, though it is not amenable to classical drug targeting as an enzyme or receptor.

Other names

Coenzyme Q4CGI-92COQ10D7SPAX10Ubiquinone biosynthesis protein COQ4 homolog, mitochondrial4-hydroxy-3-methoxy-5-polyprenylbenzoate decarboxylase

Drugs (supplements) substitute for deficient coenzyme Q in mitochondrial electron transport and antioxidant defense; this is replacement therapy, not inhibition/activation of COQ4 itself