Drug export activity of the human canalicular multispecific organic anion transporter in polarized kidney MDCK cells expressing cMOAT (MRP2) cDNA
Drug export activity of the human canalicular multispecific organic anion transporter in polarized kidney MDCK cells expressing cMOAT (MRP2) cDNA
复制标题
DOI：
10.1172/jci928
复制
发表时间：
1998-04-01
影响因子：
15.9
通讯作者：
Borsi, P
中科院分区：
文献类型：
--
作者：
Evers, R;Kool, M;Borsi, P
肝细胞的小管（顶）膜含有臂ATP依赖性有机阴离子转运系统，称为多特异性有机阴离子转运蛋白（cMOAT），推导的cMOAT的氨基酸序列与人类多药耐药相关蛋白（MRP）MRP1的氨基酸序列有49%相同，并且cMOAT和MRP1是同一腺嘌呤核苷酸结合盒转运蛋白亚家族的成员。与MRP1相反，cMOAT主要存在于非极化细胞的细胞内，这表明cMOAT需要极化细胞进行质膜路由，因此，我们在极化肾上皮MDCK细胞系中表达cMOAT cDNA，当这些细胞在单层中生长时，cMOAT定位于顶端质膜，我们证明cMOAT导致有机阴离子S-(2,4-二硝基苯基)谷胱甘肽（谷胱甘肽）的转运依他尼酸和 S-(PGA(1))-谷胱甘肽（一种先前未显示可被有机阴离子转运蛋白转运的底物）的缀合物，已知可阻断 MRP1 的化合物只能低效地抑制转运。我们还表明，cMOAT 导致抗癌药物长春碱转运至细胞单层的顶端。我们得出结论，cMOAT 是一种 5'-三磷酸腺苷结合盒转运蛋白，可能参与哺乳动物细胞的耐药性。
The canalicular (apical) membrane of the hepatocyte contains arm ATP-dependent transport system for organic anions, known as the multispecific organic anion transporter (cMOAT), The deduced amino acid sequence of cMOAT is 49% identical to that of the human multidrug resistance-associated protein (MRP) MRP1, and cMOAT and MRP1 are members of the same sub-family of adenine nucleotide binding cassette transporters. In contrast io MRP1, cMOAT was predominantly found intracellularly in nonpolarized cells, suggesting that cMOAT requires a polarized cell for plasma membrane routing, Therefore, we expressed cMOAT cDNA in polarized kidney epithelial MDCK cell lines, When these cells are grown in a monolayer, cMOAT localizes to the apical plasma membrane, We demonstrate that cMOAT causes transport of the organic anions S-(2,4-dinitrophenyl)glutathione, the glutathione conjugate of ethacrynic acid, and S-(PGA(1))-glutathione, a substrate not shown to be transported by organic anion transporters previously, Transport is inhibited only inefficiently by compounds known to block MRP1. We also show that cMOAT causes transport of the anticancer drug vinblastine to the apical side of a cell monolayer, We conclude that cMOAT is a 5'-adenosine triphosphate binding cassette transporter that potentially might be involved in drug resistance in mammalian cells.