ABCB4基因属于ATP结合盒(ABC)转运蛋白超家族,具体属于B亚家族(ABCB),该家族成员通常作为跨膜转运蛋白参与多种物质的主动运输,依赖ATP水解提供能量。ABCB4基因编码的蛋白也被称为多药耐药蛋白3(MDR3),主要在肝脏胆管膜上表达,负责将磷脂(尤其是磷脂酰胆碱)从肝细胞转运至胆汁中,这对胆汁的形成和胆固醇的溶解至关重要。ABCB4的功能异常会导致胆汁中磷脂含量不足,使胆固醇结晶析出,引发胆汁淤积性疾病如进行性家族性肝内胆汁淤积症3型(PFIC3)和妊娠期肝内胆汁淤积症(ICP)。突变可能造成蛋白折叠错误、膜定位障碍或转运活性丧失,表现为黄疸、瘙痒及肝纤维化等症状。若ABCB4过表达可能增强胆汁磷脂分泌,理论上可改善胆固醇结石的溶解,但过度活跃可能扰乱胆汁成分平衡;而表达降低会直接导致胆汁磷脂缺乏,促使胆结石形成并损伤胆管上皮。该基因与ABCB1(MDR1/P-gp)等家族成员共享典型的ABC转运蛋白结构域,包括核苷酸结合域(NBD)和跨膜域(TMD),但底物特异性不同——ABCB1主要外排药物分子,而ABCB4专一性转运磷脂。研究还发现ABCB4单核苷酸多态性(SNPs)可能影响药物代谢,例如某些患者对化疗药物敏感性的差异。此外,ABCB4表达受核受体FXR和LXR调控,与脂代谢网络相关联,其表达异常可能间接影响其他脂相关基因(如CYP7A1)的功能。
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 function of this protein has not yet been determined; however, it may involve transport of phospholipids from liver hepatocytes into bile. Alternative splicing of this gene results in several products of undetermined function. [provided by RefSeq, Jul 2008]
由该基因编码的膜相关蛋白是ATP结合盒(ABC)转运蛋白的超家族中的一员。 ABC蛋白质跨越预算外内和细胞膜输送各种分子。 ABC基因被分为七个不同亚科(ABC1,MDR / TAP,MRP,ALD,OABP,GCN20,白色)。这种蛋白是对MDR / TAP亚科的成员。耐多药/ TAP亚家族成员都参与了多药耐药以及抗原提呈。该基因编码的膜蛋白的P-糖蛋白家族的一个完整的转运和构件用磷脂作为其底物。这种蛋白质的功能尚未确定;然而,它可能涉及从肝细胞磷脂的转运到胆汁。该基因的可变剪接导致未确定功能的几款产品。 [由RefSeq的,2008年7月提供]
ABCB4基因(以及对应的蛋白质)的细胞分布位置:
ABCB4基因的本体(GO)信息:
名称 |
---|
2010 ABC transporters [PATH:hsa02010] |
4976 Bile secretion [PATH:hsa04976] |
名称 |
---|
Fatty acid, triacylglycerol, and ketone body metabolism |
Metabolism |
Metabolism of lipids and lipoproteins |
PPARA activates gene expression |
Regulation of lipid metabolism by Peroxisome proliferator-activated receptor alpha (PPARalpha) |
疾病名称 | 关系值 | NofPmids | NofSnps | 来源 |
Cholestasis, progressive familial intrahepatic 3 | 0.560542884 | 9 | 8 | BeFree_CLINVAR_CTD_human_MGD_ORPHANET_UNIPROT |
Low phospholipid-associated cholelithiasis | 0.442442977 | 15 | 0 | BeFree_CTD_human_MGD_ORPHANET_UNIPROT |
Cholestasis of pregnancy | 0.246786047 | 25 | 0 | BeFree_CTD_human_ORPHANET |
CHOLESTASIS, INTRAHEPATIC, OF PREGNANCY 3 | 0.24 | 3 | 7 | CLINVAR_UNIPROT |
Liver carcinoma | 0.201628651 | 7 | 0 | BeFree_CTD_human_MGD |
Progressive intrahepatic cholestasis (disorder) | 0.127871814 | 30 | 0 | BeFree_CTD_human |
Biliary cirrhosis | 0.126448592 | 7 | 0 | BeFree_CTD_human_GAD_LHGDN |
Cholangitis, Sclerosing | 0.123181358 | 4 | 0 | BeFree_CTD_human_GAD |
Inflammation | 0.122367032 | 2 | 0 | CTD_human_GAD |
Liver Cirrhosis | 0.121085767 | 6 | 0 | BeFree_CTD_human |
山东省济南市章丘区文博路2号 齐鲁师范学院 genelibs生信实验室
山东省济南市高新区舜华路750号大学科技园北区F座4单元2楼
电话: 0531-88819269
E-mail: product@genelibs.com
关注微信订阅号,实时查看信息,关注医学生物学动态。