Succinate dehydrogenase complex, subunit A, flavoprotein (Fp)
Complex II of the respiratory chain, which is specifically involved in the oxidation of succinate, carries electrons from FADH to CoQ. The complex is composed of four nuclear-encoded subunits and is localized in the mitochondrial inner membrane. The 70 kDa flavoprotein subunit contains a characteristic cysteine triplet. Mutations in the flavoprotein subunit gene have been linked to a form of mitochondrial respiratory chain deficiency known as Leigh syndrome.