Anti-UGT1A4

This gene encodes a UDP-glucuronosyltransferase, an enzyme of the glucuronidation pathway that transforms small lipophilic molecules, such as steroids, bilirubin, hormones, and drugs, into water-soluble, excretable metabolites. This gene is part of a complex locus that encodes several UDP-glucuronosyltransferases. The locus includes thirteen unique alternate first exons followed by four common exons. Four of the alternate first exons are considered pseudogenes. Each of the remaining nine 5' exons may be spliced to the four common exons, resulting in nine proteins with different N-termini and identical C-termini. Each first exon encodes the substrate binding site, and is regulated by its own promoter. This enzyme has some glucuronidase activity towards bilirubin, although is is more active on amines, steroids, and sapogenins. Protein function: [Isoform 1]: UDP-glucuronosyltransferase (UGT) that catalyzes phase II biotransformation reactions in which lipophilic substrates are conjugated with glucuronic acid to increase the metabolite's water solubility, thereby facilitating excretion into either the urine or bile (PubMed:18177842, PubMed:24641623). Essential for the elimination and detoxification of drugs, xenobiotics and endogenous compounds (PubMed:18177842). Involved in the glucuronidation of calcidiol, which is the major circulating form of vitamin D3 essential for the regulation of calcium and phosphate homeostasis (PubMed:24641623). Also glucuronidates the biologically active form of vitamin D3, calcitriol, probably leading to its biliary transport and intestinal reabsorption (PubMed:18177842). [The UniProt Consortium]