NADH dehydrogenase [ubiquinone] flavoprotein 3, mitochondrial is a protein in humans that is encoded by NDUFV3 gene. Accessory subunit of the mitochondrial membrane respiratory chain NADH dehydrogenase (Complex I), that is believed not to be involved in 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. May be the terminally assembled subunit of Complex I.