NADH-ubiquinone oxidoreductase chain 3 MT-ND3 MTND3 ND3 NADH dehydrogenase subunit 3 115 NU3M_HORSE NADH3 MNLMLTLLTNTLLASLLVLIAFWLPQLNIYAEKTSPYECGFDPMGSARLPFSMKFFLVAITFLLFDLEIALLLPLPWASQTTNLNTMLIMALVLISLLAISLAYEWTQKGLEWTE Core subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I) that is believed to belong to the minimal assembly required for catalysis. Complex I functions in the transfer of electrons from NADH to the respiratory chain. The immediate electron acceptor for the enzyme is believed to be ubiquinone (By similarity).