FTO overexpression in liver of mice regulates mitochondrial density and funtion. Liver of mice were infected with recombinant adenovirus encoding human FTO or GFP (control) proteins for 10 days (2.108ifu/g of body weight). A) Effect of FTO on mtDNA quantity, calculated as the ratio of COX1 to cyclophilin A DNA levels, and measured by real-time PCR in the liver of infected mice. B) Effect of FTO on the mRNA levels of POLG1, POLG2, SSBP1, TFAM, NRF1, NRF2, COX3 measured by real-time PCR in the liver of Ad-GFP and Ad-FTO mice. C) Effect of FTO on oxygen consumption of mitochondria isolated from liver of Ad-GFP and Ad-FTO mice. Data are means ± SEM (n = 5/group). *p < 0.05 compared to GFP infected mice.