Abstract
NADH dehydrogenase (ubiquinone) Fe-S protein 7 (NDUFS7) is one of the nuclear-encoded and highly conserved core subunits of mitochondrial complex I. This protein houses the tetranuclear iron-sulfur cluster N2, which is the terminal receptor of electrons and the reducer for quinone in complex I peripheral arm. NDUFS7 protein plays a critical role in complex I assembly and activity, according to the results of studies from simple organisms and human disease models. Mutations of NDUFS7 have been associated with Leigh Syndrome and bipolar disorder. To detailedly investigate the role of NDUFS7 in mitochondrial complex I of human cells, NDUFS7 was suppressed in human T-REx293 cells by RNA interference system in this study. In the NDUFS7 knockdown cells, the growth rate, ATP generation, oxygen consumption and complex I activity were reduced. These results provided the evidence of the essential role of NDUFS7 for complex I activity and energy production in human cells.