Anticorps UGT1A1

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. Is also able to catalyze the glucuronidation of 17beta-estradiol, 17alpha-ethinylestradiol, 1-hydroxypyrene, 4-methylumbelliferone, 1-naphthol, paranitrophenol, scopoletin, and umbelliferone. Isoform 2 lacks transferase activity but acts as a negative regulator of isoform 1.

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. The preferred substrate of this enzyme is bilirubin, although it also has moderate activity with simple phenols, flavones, and C18 steroids. Mutations in this gene result in Crigler-Najjar syndromes types I and II and in Gilbert syndrome.

Isoform 1 and isoform 2 are expressed in liver, colon and small intestine. Isoform 2 but not isoform 1 is expressed in kidney. Isoform 1 and isoform 2 are not expressed in esophagus. Not expressed in skin.

Gilbert syndrome: Occurs as a consequence of reduced bilirubin transferase activity and is often detected in young adults with vague non-specific complaints.

Transient familial neonatal hyperbilirubinemia: A condition characterized by excessive concentration of bilirubin in the blood, which may lead to jaundice. Breast milk jaundice is a common problem in nursing infants.

Crigler-Najjar syndrome 1: 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.

Crigler-Najjar syndrome 2: 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.

Belongs to the UDP-glycosyltransferase family.

Microsome. Endoplasmic reticulum membrane.