NQO1 is a 274aa protein belonging to the NAD(P)H dehydrogenase (quinone) family. Its enzymatic activity prevents reduction of quinones that results in the production of radical species and is involved in detoxification pathways as well as in biosynthetic processes such as the vitamin K-dependent gamma-carboxylation of glutamate residues in prothrombin synthesis. It plays a role in regulating ubiquitin-independent degradation of ornithine decarboxylase by the 20S proteasome and regulates p53 proteasomal degradation in cancer. Defects in NQO1 lead to tardive dyskinesia (TD), an increased risk of hematotoxicity after exposure to benzene, susceptibility to various forms of cancer and Alzheimer's disease (AD). It is widely expressed.