Seroatlas · Human Serome Atlas

UGT1A1

UDP-glucuronosyltransferase 1A1

Also known as: GNT1, UD11_HUMAN, UGT1, UGT1A

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P22309
Gene
UGT1A1
Ensembl
ENSG00000241635
Chromosome
2
Canonical length
533 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted membrane proteins
Quaternary structure
Homodimer

OverviewNCBI 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. 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. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

533 residues, UniProt reviewed canonical sequence.

>P22309|UGT1A1
     1  MAVESQGGRP LVLGLLLCVL GPVVSHAGKI LLIPVDGSHW LSMLGAIQQL QQRGHEIVVL
    61  APDASLYIRD GAFYTLKTYP VPFQREDVKE SFVSLGHNVF ENDSFLQRVI KTYKKIKKDS
   121  AMLLSGCSHL LHNKELMASL AESSFDVMLT DPFLPCSPIV AQYLSLPTVF FLHALPCSLE
   181  FEATQCPNPF SYVPRPLSSH SDHMTFLQRV KNMLIAFSQN FLCDVVYSPY ATLASEFLQR
   241  EVTVQDLLSS ASVWLFRSDF VKDYPRPIMP NMVFVGGINC LHQNPLSQEF EAYINASGEH
   301  GIVVFSLGSM VSEIPEKKAM AIADALGKIP QTVLWRYTGT RPSNLANNTI LVKWLPQNDL
   361  LGHPMTRAFI THAGSHGVYE SICNGVPMVM MPLFGDQMDN AKRMETKGAG VTLNVLEMTS
   421  EDLENALKAV INDKSYKENI MRLSSLHKDR PVEPLDLAVF WVEFVMRHKG APHLRPAAHD
   481  LTWYQYHSLD VIGFLLAVVL TVAFITFKCC AYGYRKCLGK KGRVKKAHKS KTH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against UGT1A1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
345 nTPM

Expression across tissuesHPA

Tissue

  • liver: 345 nTPM
  • duodenum: 189 nTPM
  • small intestine: 75 nTPM
  • urinary bladder: 9.3 nTPM
  • kidney: 3.7 nTPM
  • esophagus: 3.3 nTPM

Single-cell type

  • hepatocytes: 0.4 nCPM
  • epididymal basal cells: 0.2 nCPM
  • urothelial cells: 0.2 nCPM
  • enterocytes: 0.1 nCPM
  • adipocytes: 0 nCPM
  • adrenal cortex cells: 0 nCPM

Immune cell

  • neutrophil: 1.4 nTPM
  • basophil: 0.8 nTPM
  • NK-cell: 0.3 nTPM
  • naive B-cell: 0.2 nTPM
  • classical monocyte: 0.1 nTPM
  • eosinophil: 0.1 nTPM

Brain region

  • cerebellum: 9.7 nTPM
  • hypothalamus: 8.5 nTPM
  • cerebral cortex: 8.1 nTPM
  • basal ganglia: 7.8 nTPM
  • white matter: 7.8 nTPM
  • amygdala: 7.3 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about UGT1A1.

Disease | AllUniProt

Conditions UGT1A1 is implicated in, by any mechanism.

Disease | GeneticClinVar

74 pathogenic / likely-pathogenic of 343 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Crigler-Najjar syndrome type 1
  • Gilbert syndrome
  • Crigler-Najjar syndrome, type II
  • Lucey-Driscoll syndrome
  • BILIRUBIN, SERUM LEVEL OF, QUANTITATIVE TRAIT LOCUS 1

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.08
gnomAD pLI
0
gnomAD missense Z
-0.25
DepMap mean gene effect
0.07
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of UGT1A1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads UGT1A1 as an antibody target. Whether an autoantibody or antibody against UGT1A1 could matter depends on whether native UGT1A1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

UGT1A1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label UGT1A1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/UGT1A1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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