ATP-binding cassette sub-family G member 2; placenta-specific ATP-binding cassette transporter; breast cancer resistance protein; mitoxantrone resistance-associated protein; CDw338; CD338 (ABCG2, ABCP, BCRP, BCRP1, MXR)

Function

• xenobiotic transporter
• may play a role in the exclusion of xenobiotics from the brain
• may be involved in brain-to-blood efflux
• appears to play a role in the multidrug resistance phenotype of several cancer cell lines
• when overexpressed, the transfected cells become resistant to mitoxantrone, daunorubicin & doxorubicin, display diminished intracellular accumulation of daunorubicin, & manifest an ATP- dependent increase in the efflux of rhodamine 123
• glycosylation-deficient ABCG2 is normally expressed & functional

Structure

• monomer or homodimer
• disulfide-linked belongs to the ABC transporter family, ABCG (White) subfamily
• contains 1 ABC transporter domain

Compartment

cell membrane

Alternative splicing

named isoforms=2

Expression

• highly expressed in placenta
• low expression in small intestine, liver & colon

Pathology

up-regulated in brain tumors

More general terms

• transmembrane 6 protein
• ATP-binding cassette sub-family G (ABC transporter-G, ABG)
• CD antigen
• glycoprotein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:9429
• OMIM: https://mirror.omim.org/entry/603756
• UniProt: http://www.uniprot.org/uniprot/Q9UNQ0.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=9429