Predicted to enable NAD binding activity; oxidoreductase activity, acting on NAD(P)H; and quinone binding activity. Predicted to be involved in mitochondrial electron transport, NADH to ubiquinone. Predicted to be part of mitochondrial respiratory chain complex I. Human ortholog(s) of this gene implicated in several diseases, including Leigh disease; multiple sclerosis; and nuclear type mitochondrial complex I deficiency 6. Is an ortholog of human NDUFS2 (NADH:ubiquinone oxidoreductase core subunit S2).