UROC1 Full-Length MS Protein Standard (NP_653240), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. This gene encodes an enzyme involved in histidine catabolism, metabolizing urocanic acid to formiminoglutamic acid. The gene product is known to protect the skin from ultra violet rays and is contained in human sweat. Deficiency of this gene product in the liver is an apparent cause of mental retardation. Multiple transcript variants encoding different isoforms have been found for this gene.