ABCG2

ABCG2
Identifiers
Aliases	ABCG2, ATP-binding cassette, sub-family G (WHITE), member 2 (Junior blood group), ABC15, ABCP, BCRP, BCRP1, BMDP, CD338, CDw338, EST157481, GOUT1, MRX, MXR, MXR1, UAQTL1, MXR-1, ATP binding cassette subfamily G member 2 (Junior blood group)
External IDs	OMIM: 603756 MGI: 1347061 HomoloGene: 55852 GeneCards: ABCG2
Gene location (Human) Chr. Chromosome 4 (human)[1] Band 4q22.1 Start 88,090,150 bp[1] End 88,231,628 bp[1]
Gene location (Mouse) Chr. Chromosome 6 (mouse)[2] Band 6 B3|6 27.82 cM Start 58,584,523 bp[2] End 58,695,676 bp[2]
RNA expression pattern Bgee Top expressed in jejunal mucosa duodenum small intestine colon sigmoid colon More reference expression data BioGPS More reference expression data
Gene ontology Molecular function nucleotide binding ABC-type xenobiotic transporter activity heme transmembrane transporter activity protein homodimerization activity transporter activity ATPase activity GO:0001948 protein binding ATP binding ATPase-coupled transmembrane transporter activity GO:0017127 cholesterol transfer activity identical protein binding GO:0015238 xenobiotic transmembrane transporter activity Cellular component mitochondrial membrane membrane mitochondrion nucleus plasma membrane integral component of membrane apical plasma membrane receptor complex Biological process urate metabolic process cellular iron ion homeostasis heme transport xenobiotic transmembrane transport xenobiotic transport transmembrane transport cholesterol efflux cellular detoxification Sources:Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	9429	26357
Ensembl	ENSG00000118777	ENSMUSG00000029802
UniProt	Q9UNQ0	Q7TMS5
RefSeq (mRNA)	NM_001257386 NM_004827 NM_001348985 NM_001348986 NM_001348987 NM_001348988 NM_001348989	NM_011920 NM_001355477 NM_001381925 NM_001381926 NM_001381927
RefSeq (protein)	NP_001244315 NP_004818 NP_001335914 NP_001335915 NP_001335916 NP_001335917 NP_001335918	NP_036050 NP_001342406 NP_001368854 NP_001368855 NP_001368856
Location (UCSC)	Chr 4: 88.09 – 88.23 Mb	Chr 6: 58.58 – 58.7 Mb
PubMed search	[3]	[4]
Wikidata
View/Edit Human View/Edit Mouse

ATP-binding cassette super-family G member 2 is a protein that in humans is encoded by the ABCG2 gene.^[5][6] ABCG2 has also been designated as CDw338 (cluster of differentiation w338).

Function[]

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 the breast cancer resistance protein (BCRP), this protein functions as a xenobiotic transporter which may play a role in multi-drug resistance to chemotherapeutic agents including mitoxantrone and camptothecin analogues. Early observations of significant ABCG2-mediated resistance to anthracyclines were subsequently attributed mutations encountered in vitro but not in nature or the clinic. Significant expression of this protein has been observed in the placenta,^[7] and it has been shown to have a role in protecting the fetus from xenobiotics in the maternal circulation.^[8]

The transporter has been shown to play protective roles in blocking absorption at the apical membrane of the intestine, and at the blood-testis barrier,^[8] the blood–brain barrier,^[8] and the membranes of hematopoietic progenitor and other stem cells. At the apical membranes of the liver and kidney, it enhances excretion of xenobiotics. In the lactating mammary gland, it has a role on excreting vitamins such as riboflavin and biotin into milk.^[8] In the kidney and gastrointestinal tract, it has a role in urate excretion.

The protein also carries the Jr(a) antigen, which defines the Junior blood group system.^[9]

Interactive pathway map[]

Click on genes, proteins and metabolites below to link to respective articles.[§ 1] [[File: [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] |alt=Fluorouracil (5-FU) Activity edit]] Fluorouracil (5-FU) Activity edit ^ The interactive pathway map can be edited at WikiPathways: "FluoropyrimidineActivity_WP1601".

Click on genes, proteins and metabolites below to link to respective articles. [§ 1] [[File: [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] [[ ]] |alt=Irinotecan Pathway edit]] Irinotecan Pathway edit ^ The interactive pathway map can be edited at WikiPathways: "IrinotecanPathway_WP46359".

Inhibition[]

It is inhibited by some calcium channel blockers such as amlodipine, felodipine and nifedipine.^[10]

See also[]

• ATP-binding cassette transporter

References[]

Further reading[]

External links[]

• ABCG2+protein,+human at the US National Library of Medicine Medical Subject Headings (MeSH)
• Human ABCG2 genome location and ABCG2 gene details page in the UCSC Genome Browser.
• Overview of all the structural information available in the PDB for UniProt: Q9UNQ0 (Broad substrate specificity ATP-binding cassette transporter ABCG2) at the PDBe-KB.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.