Probable transporter, its substrate specificity is unknown. Expressed in testis (at protein level). Widely expressed at low level (PubMed:11483364, PubMed:11688999, PubMed:12011458, PubMed:17472575). Isoform 5 is specifically expressed in brain, testis and breast cancer cells (PubMed:11483364, PubMed:11688999, PubMed:12011458). Expressed in fetal tissues. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the ABC transporter superfamily. ABCC family. Conjugate transporter (TC 3.A.1.208) subfamily. Does not transport any of the organic anions transported by the other multidrug resistance-associated proteins (MRPs) in vesicular transport assays, nor does it confer resistance to cytotoxic agents in intact cell assays. Database for mutations in ABC proteins