A NAD(P)H-dependent oxidoreductase involved in cellular oxidative stress response. At the plasma membrane, catalyzes reduction of coenzyme Q/ubiquinone-10 to ubiquinol-10, a lipophilic radical-trapping antioxidant that prevents lipid oxidative damage and consequently ferroptosis. Cooperates with GPX4 to suppress phospholipid peroxidation and ferroptosis. This anti-ferroptotic function is independent of cellular glutathione levels (By similarity). May play a role in mitochondrial oxidative signaling (PubMed:26689472). Upon oxidative stress, associates with the lipid peroxidation end product 4-hydroxy-2-nonenal (HNE) forming a lipid adduct devoid of oxidoreductase activity, which then translocates from mitochondria into the nucleus triggering DNA damage and cell death (PubMed:26689472). Capable of DNA binding in a non-sequence specific way (By similarity). H(+) + NADH + ubiquinone-10 = NAD(+) + ubiquinol-10 Binds 6-hydroxy-FAD non-covalently. The modification by 4-hydroxy-2-nonenal (HNE) adduction in mitochondria results in loss of the oxidoreductase activity and activation of a novel function in mitochondrial oxidative stress signaling. Interacts with importin subunits KPNA2 and IPO5; this interaction likely mediates the translocation into the nucleus upon oxidative stress. Detected in most normal tissues as two transcripts of 1.8 and 4.0 kb in length, respectively. Highly expressed in liver, testis, and kidney, and expressed at lower levels in pancreas, spleen, brain and lung (PubMed:16186796). Expressed in heart (at protein level) (PubMed:26689472). Expression is up-regulated in mouse embryonic fibroblasts by genotoxic reagents 5-fluorouracil and etoposide (PubMed:16186796). Up-regulated in cardiac cells by anticancer drug doxorubicin (PubMed:26689472). N-myristoylation at Gly-2 mediates the recruitment to lipid droplets and plasma membrane. Belongs to the FAD-dependent oxidoreductase family. Truncated C-terminus.