Mediates export of organic anions and drugs from the cytoplasm (PubMed:
7961706, PubMed:
16230346, PubMed:
9281595, PubMed:
10064732, PubMed:
11114332). Mediates ATP-dependent transport of glutathione and glutathione conjugates, leukotriene C4, estradiol-17- beta-o-glucuronide, methotrexate, antiviral drugs and other xenobiotics (PubMed:
7961706, PubMed:
16230346, PubMed:
9281595, PubMed:
10064732, PubMed:
11114332). Confers resistance to anticancer drugs by decreasing accumulation of drug in cells, and by mediating ATP- and GSH-dependent drug export (PubMed:
9281595). Hydrolyzes ATP with low efficiency (PubMed:
16230346). Catalyzes the export of sphingosine 1-phosphate from mast cells independently of their degranulation (PubMed:
17050692). Participates in inflammatory response by allowing export of leukotriene C4 from leukotriene C4-synthezing cells (By similarity).