Seroatlas · Human Serome Atlas

NR1I3

Nuclear receptor subfamily 1 group I member 3

Also known as: CAR, CAR1, MB67, NR1I3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q14994
Gene
NR1I3
Ensembl
ENSG00000143257
Chromosome
1
Canonical length
352 aa
Protein class
Nuclear receptors, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene encodes a member of the nuclear receptor superfamily, and is a key regulator of xenobiotic and endobiotic metabolism. The protein binds to DNA as a monomer or a heterodimer with the retinoid X receptor and regulates the transcription of target genes involved in drug metabolism and bilirubin clearance, such as cytochrome P450 family members. Unlike most nuclear receptors, this transcriptional regulator is constitutively active in the absence of ligand but is regulated by both agonists and inverse agonists. Ligand binding results in translocation of this protein to the nucleus, where it activates or represses target gene transcription. These ligands include bilirubin, a variety of foreign compounds, steroid hormones, and prescription drugs. In addition to drug metabolism, the CAR protein is also reported to regulate genes involved in glucose metabolism, lipid metabolism, cell proliferation, and circadian clock regulation. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2020]

Canonical amino-acid sequenceUniProt

352 residues, UniProt reviewed canonical sequence.

>Q14994|NR1I3
     1  MASREDELRN CVVCGDQATG YHFNALTCEG CKGFFRRTVS KSIGPTCPFA GSCEVSKTQR
    61  RHCPACRLQK CLDAGMRKDM ILSAEALALR RAKQAQRRAQ QTPVQLSKEQ EELIRTLLGA
   121  HTRHMGTMFE QFVQFRPPAH LFIHHQPLPT LAPVLPLVTH FADINTFMVL QVIKFTKDLP
   181  VFRSLPIEDQ ISLLKGAAVE ICHIVLNTTF CLQTQNFLCG PLRYTIEDGA RVSPTVGFQV
   241  EFLELLFHFH GTLRKLQLQE PEYVLLAAMA LFSPDRPGVT QRDEIDQLQE EMALTLQSYI
   301  KGQQRRPRDR FLYAKLLGLL AELRSINEAY GYQIQHIQGL SAMMPLLQEI CS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against NR1I3 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.3
Highest tissue expression
159 nTPM

Expression across tissuesHPA

Tissue

  • liver: 159 nTPM
  • kidney: 9.4 nTPM
  • small intestine: 3.4 nTPM
  • basal ganglia: 2.8 nTPM
  • duodenum: 2.2 nTPM
  • pituitary gland: 1.6 nTPM

Single-cell type

  • hepatocytes: 195 nCPM
  • cardiomyocytes: 26 nCPM
  • epicardial cells: 9.1 nCPM
  • proximal tubule cells: 8.9 nCPM
  • enterocytes: 7.6 nCPM
  • early spermatids: 7.4 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • basal ganglia: 8.3 nTPM
  • cerebral cortex: 5.2 nTPM
  • white matter: 4.8 nTPM
  • cerebellum: 4.6 nTPM
  • pons: 4.3 nTPM
  • medulla oblongata: 4.1 nTPM

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)
1.15
gnomAD pLI
0
gnomAD missense Z
0.81
DepMap mean gene effect
-0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 NR1I3 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 NR1I3 as an antibody target. Whether an autoantibody or antibody against NR1I3 could matter depends on whether native NR1I3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

NR1I3 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 NR1I3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/NR1I3. 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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