UDP glucuronosyltransferase family 1 member A4
The information on this page was automatically extracted from online scientific databases.
From NCBI Gene:
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. [provided by RefSeq, Jul 2008]
UDPGT is of major importance in the conjugation and subsequent elimination of potentially toxic xenobiotics and endogenous compounds. This isoform glucuronidates bilirubin IX-alpha to form both the IX-alpha-C8 and IX-alpha-C12 monoconjugates and diconjugate. Isoform 2 lacks transferase activity but acts as a negative regulator of isoform 1.
Gilbert syndrome (GILBS): Occurs as a consequence of reduced bilirubin transferase activity and is often detected in young adults with vague non-specific complaints. [MIM:143500]
Crigler-Najjar syndrome 1 (CN1): Patients have severe hyperbilirubinemia and usually die of kernicterus (bilirubin accumulation in the basal ganglia and brainstem nuclei) within the first year of life. CN1 inheritance is autosomal recessive. [MIM:218800]
Crigler-Najjar syndrome 2 (CN2): Patients have less severe hyperbilirubinemia and usually survive into adulthood without neurologic damage. Phenobarbital, which induces the partially deficient glucuronyl transferase, can diminish the jaundice. CN2 inheritance is autosomal dominant. [MIM:606785]
- UDPGT 1-4