Genetic inhibition of mitochondrial biogenesis factor TFAM rescues effects of oxidative stress. (A-B) OCI-AML-2 cells were infected with TFAM targeting shRNAs or control sequences in lentiviral vectors. Four days posttransduction, TFAM mRNA expression relative to 18S was made by qRT-PCR (A) and TFAM protein expression was determined by immunoblotting (B). (C) DNA was extracted from cells, and quantitative PCR was used to measure levels of ND1 relative to HGB. ND1/HGB ratio is shown relative to control cells. (D) Citrate synthase activity as a marker of mitochondrial mass was determined in TFAM knockdown clones. (E) Basal OCR was shown after 1 hour of incubation in cell chambers. (F) Activity of complex III was measured in control and TFAM knockdown cells. Left panel shows complex activity was normalized to total protein concentration. Right panel shows complex activity was normalized to mitochondrial mass using citrate synthase activity. Data represent the mean complex activity ± standard deviation (SD) from representative experiments performed in triplicate. TFAM knockdown experiments in AML cells were repeated twice. In all panels, *P < .05; **P < .001; ***P < .0001 as determined by the unpaired Student t test.