Core subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I which catalyzes electron transfer from NADH through the respiratory chain, using ubiquinone as an electron acceptor. Essential for the catalytic activity and assembly of complex I.,MTND4,MT-ND4,Endocrine & Metabolism,Mitochondrial metabolism,Neuroscience,Neurodegenerative Diseases,MT-ND4