ABCB4（ATP binding cassette subfamily B member 4），癌症关联基因，基因ID：5244，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蛋白通过细胞外和细胞内的膜运输各种分子。abc基因分为七个不同的亚家族（abc1，mdr/tap，mrp，ald，oabp，gcn20，white）。这种蛋白质是mdr/tap亚家族的一员。mdr/tap亚家族成员参与多药耐药和抗原递呈。该基因编码以卵磷脂为底物的膜蛋白p-糖蛋白家族的一个全转运体和成员。这种蛋白质的功能尚未确定，但它可能涉及磷脂从肝细胞运输到胆汁。这个基因的选择性剪接导致了一些功能不确定的产物。[由RefSeq提供，2008年7月]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 as well as antigen presentation. This gene encodes a full transporter and member of the p-glycoprotein family of membrane proteins with phosphatidylcholine as its substrate. The fu。