Seroatlas · Human Serome Atlas

ABCG2

Broad substrate specificity ATP-binding cassette transporter ABCG2

Also known as: ABCG2_HUMAN, ABCP, BCRP, CD338, EST157481, MXR

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

Protein identityUniProt · HPA

UniProt accession
Q9UNQ0
Gene
ABCG2
Ensembl
ENSG00000118777
Chromosome
4
Canonical length
655 aa
Protein class
Cancer-related genes, CD markers, Enzymes, Human disease related genes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins, Transporters
Subcellular location
Nucleoplasm,Plasma membrane
Quaternary structure
Homotetramer

OverviewNCBI Gene

The membrane-associated protein encoded by this gene is included in the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the White subfamily. Alternatively referred to as a breast cancer resistance protein, this protein functions as a xenobiotic transporter which may play a major role in multi-drug resistance. It likely serves as a cellular defense mechanism in response to mitoxantrone and anthracycline exposure. Significant expression of this protein has been observed in the placenta, which may suggest a potential role for this molecule in placenta tissue. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Apr 2012]

Canonical amino-acid sequenceUniProt

655 residues, UniProt reviewed canonical sequence.

>Q9UNQ0|ABCG2
     1  MSSSNVEVFI PVSQGNTNGF PATASNDLKA FTEGAVLSFH NICYRVKLKS GFLPCRKPVE
    61  KEILSNINGI MKPGLNAILG PTGGGKSSLL DVLAARKDPS GLSGDVLING APRPANFKCN
   121  SGYVVQDDVV MGTLTVRENL QFSAALRLAT TMTNHEKNER INRVIQELGL DKVADSKVGT
   181  QFIRGVSGGE RKRTSIGMEL ITDPSILFLD EPTTGLDSST ANAVLLLLKR MSKQGRTIIF
   241  SIHQPRYSIF KLFDSLTLLA SGRLMFHGPA QEALGYFESA GYHCEAYNNP ADFFLDIING
   301  DSTAVALNRE EDFKATEIIE PSKQDKPLIE KLAEIYVNSS FYKETKAELH QLSGGEKKKK
   361  ITVFKEISYT TSFCHQLRWV SKRSFKNLLG NPQASIAQII VTVVLGLVIG AIYFGLKNDS
   421  TGIQNRAGVL FFLTTNQCFS SVSAVELFVV EKKLFIHEYI SGYYRVSSYF LGKLLSDLLP
   481  MRMLPSIIFT CIVYFMLGLK PKADAFFVMM FTLMMVAYSA SSMALAIAAG QSVVSVATLL
   541  MTICFVFMMI FSGLLVNLTT IASWLSWLQY FSIPRYGFTA LQHNEFLGQN FCPGLNATGN
   601  NPCNYATCTG EEYLVKQGID LSPWGLWKNH VALACMIVIF LTIAYLKLLF LKKYS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ABCG2 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
Cell surface
Secreted
No
Transmembrane segments
6
Mean surface accessibility (rSASA)
0.29
Highest tissue expression
83 nTPM

Expression across tissuesHPA

Tissue

  • small intestine: 83 nTPM
  • duodenum: 45 nTPM
  • liver: 34 nTPM
  • seminal vesicle: 32 nTPM
  • midbrain: 22 nTPM
  • endometrium: 22 nTPM

Single-cell type

  • breast lactating cells: 317 nCPM
  • hofbauer cells: 299 nCPM
  • enterocytes: 267 nCPM
  • vascular endothelial cells: 142 nCPM
  • extravillous trophoblasts: 116 nCPM
  • colonocytes: 105 nCPM

Immune cell

  • MAIT T-cell: 2.2 nTPM
  • NK-cell: 1.1 nTPM
  • T-reg: 0.8 nTPM
  • gdT-cell: 0.7 nTPM
  • naive B-cell: 0.5 nTPM
  • memory CD4 T-cell: 0.2 nTPM

Brain region

  • thalamus: 60 nTPM
  • pons: 60 nTPM
  • medulla oblongata: 56 nTPM
  • hypothalamus: 42 nTPM
  • white matter: 40 nTPM
  • spinal cord: 40 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)
1.55
gnomAD pLI
0
gnomAD missense Z
-0.88
DepMap mean gene effect
0.06
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ABCG2 as an antibody target. Whether an autoantibody or antibody against ABCG2 could matter depends on whether native ABCG2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ABCG2 is annotated at the cell surface, where native ABCG2 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label ABCG2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ABCG2. 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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