Human NQO-2 Antibody

NQO-2 (NADPH Quinone acceptor Oxidoreductase 2; also QR2, melatonin receptor 3/MT3 and NRH dehydrogenase) is a 25-26 kDa cytoplasmic flavoprotein member of the NAD(P)H dehydrogenase family of enzymes. It shows restricted expression, being found in retinal pigment epithelium, prostatic fibroblasts, select CNS neurons and RBCs. Like NQO-1, NQO-2 would appear to reduce catechol quinones, but without the use of NADH. In contrast to NQO-1, NQO-2 would appear to activate some quinones, generating cytotoxic products. NQO-2 also reportedly binds and stabilizes key cell protection molecules such as p53, thus acting as a gatekeeper for proteosome-mediated protein turnover. Finally, NQO-2 reportedly binds to melatonin, an act that may promote the subsequent binding of the androgen receptor and an inhibition of cell proliferation. Human NQO-2 is 231 amino acids (aa) in length. It contains a flavodoxin-like domain (aa 4-212) and three utilized Ser phosphorylation sites. NQO-2 functions as a noncovalent homodimer. There are two potential isoform variants. One shows an alternative start site at Met117, while another shows a deletion of aa 102-139. Full length human NQO-2 shares 81% aa sequence identity with mouse NQO-2, and less than 50% aa sequence identity with human NQO-1.