由该基因编码的膜相关蛋白是ATP结合盒（ABC）转运蛋白超家族的成员。ABC蛋白通过细胞外膜和细胞内膜转运各种分子。ABC基因分为7个不同的亚家族（abc1，mdr/tap，mrp，ald，oabp，gcn20，white）。这种蛋白是MDR/TAP亚家族的成员。MDR/TAP亚家族成员参与多药耐药。该基因编码的蛋白质是一种具有广泛底物特异性的外源性化合物的ATP依赖性药物外排泵。它负责减少多药耐药细胞中的药物积累，并经常介导抗肿瘤药物的发展。这种蛋白也作为血脑屏障的转运蛋白发挥作用。
The membrane-associated protein encoded by this gene is a member of 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 MDR/TAP subfamily. Members of the MDR/TAP subfamily are involved in multidrug resistance. The protein encoded by this gene is an ATP-dependent drug efflux pump for xenobiotic compounds with broad substrate specificity. It is responsible for decreased drug accumulation in multidrug-resistant cells and often mediates the development of resistance to anticancer drugs. This protein also functions as a transporter in the blood-brain barrier.