Complex I (NADH:ubiquinone oxidoreductase) is active in but non-essential for procyclic Trypanosoma brucei

0358455 - BC 2012 RIV NL eng J - Journal Article
Verner, Zdeněk - Čermáková, P. - Škodová, Ingrid - Kriegová, Eva - Horváth, A. - Lukeš, Julius
Complex I (NADH:ubiquinone oxidoreductase) is active in but non-essential for procyclic Trypanosoma brucei.
Molecular and Biochemical Parasitology. Roč. 175, č. 2 (2011), s. 196-200. ISSN 0166-6851. E-ISSN 1872-9428
R&D Projects: GA ČR GA204/09/1667; GA ČR GD206/09/H026; GA MŠMT 2B06129; GA MŠMT LC07032
Institutional research plan: CEZ:AV0Z60220518
Keywords : Trypanosoma * Mitochondrion * Respiration * Complex I
Subject RIV: EB - Genetics ; Molecular Biology
Impact factor: 2.551, year: 2011

The requirement of complex I (NADH:ubiquionone oxidoreductase) for respiration in Trypanosoma brucei is controversial. Recent identification of its homologues in mitochondrial proteome resolved a question of its presence or absence. However, with one exception, no data have been available concerning the function(s) of complex I. Here we present a functional RNAi study of 3 (NUBM, NUKM, NUEM) putative subunits of this complex. Although no changes were detected in growth, mitochondrial membrane potential or reactive oxygen species production in cell lines depleted for target transcript, the NUBM and NUKM RNAi knock-downs showed decreased specific NADH:ubiquinone oxidoreductase activity. Moreover, glycerol gradients revealed the presence of two distinct peaks of NADH dehydrogenase activity, with shifted sensitivity to inhibitors of complex I upon RNAi induction. Thus complex I is not only present in the procyclic stage, but it does participate in electron transport chain.
Permanent Link: http://hdl.handle.net/11104/0196495