Mitochondrial NADP+-isocitrate dehydrogenase Idp1 involves CoQ biosynthesis in parallel with NAD kinase Pos5.
Mitochondrial NADPH is synthesized by isocitrate dehydrogenase (Idp1) from NADP+ and NAD kinase (Pos5) from NADH. Coenzyme Q levels in Schizosaccharomyces pombe were decreased by deletion of idp1 and further lowered by deletion of pos5. The NADP+/NADPH ratio of the ∆idp1 strain shifted to an oxidized state. The mitochondrial NADPH pool and its redox state are critical for CoQ biosynthesis.
Nishihara S, Matsuo Y, Kawamukai M