Identification and characterization of human organic anion transporter 3 expressing predominantly in the kidney
Identification and characterization of human organic anion transporter 3 expressing predominantly in the kidney
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DOI：
10.1124/mol.59.5.1277
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发表时间：
2001-05-01
影响因子：
3.6
通讯作者：
Endou, H
中科院分区：
文献类型：
--
作者：
Cha, SH;Sekine, T;Endou, H
从人肾cDNA文库中分离出一种编码多特异性有机阴离子转运体3（hOAT3）的cDNA。hOAT3 cDNA由2179个碱基对组成，编码一个含543个氨基酸残基的蛋白质，具有12个假定的跨膜结构域。hOAT3推导的氨基酸序列与OAT家族其他成员有36% - 51%的同一性。Northern杂交分析显示，hOAT3 mRNA在肾脏、大脑和骨骼肌中表达。当在非洲爪蟾卵母细胞中表达时，hOAT3以不依赖钠的方式介导硫酸雌酮（Km = 3.1 μM）、对氨基马尿酸（Km = 87.2 μM）、甲氨蝶呤（Km = 10.9 μM）和西咪替丁（Km = 57.4 μM）的转运。hOAT3还介导硫酸脱氢表雄酮、赭曲霉毒素A、PGE₂、雌二醇葡糖苷酸、牛磺胆酸、戊二酸、cAMP和尿酸的转运。硫酸雌酮对通过hOAT3的[³H]硫酸雌酮的流入或流出均未显示任何转刺激作用。hOAT3与化学性质不同的阴离子化合物相互作用，如非甾体抗炎药、利尿剂、磺溴酞、青霉素G、胆汁盐和溴化四乙铵。hOAT3蛋白被证明定位于肾近端小管的基底外侧膜，通过荧光原位杂交分析确定hOAT3基因位于人类染色体11q12 - q13.3。这些结果表明hOAT3在肾脏内源性和外源性有机阴离子的排泄/解毒中起重要作用。
A cDNA encoding a multispecific organic anion transporter 3 (hOAT3) was isolated from a human kidney cDNA library. The hOAT3 cDNA consisted of 2179 base pairs that encoded a 543-amino-acid residue protein with 12 putative transmembrane domains. The deduced amino acid sequence of hOAT3 showed 36 to 51% identity to those of other members of the OAT family. Northern blot analysis revealed that hOAT3 mRNA is expressed in the kidney, brain, and skeletal muscle. When expressed in Xenopus laevis oocytes, hOAT3 mediated the transport of estrone sulfate (K-m = 3.1 muM), p-aminohippurate (K-m = 87.2 muM), methotrexate (K-m = 10.9 muM), and cimetidine (K-m = 57.4 muM) in a sodium-independent manner. hOAT3 also mediated the transport of dehydroepiandrosterone sulfate, ochratoxin A, PGE(2), estradiol glucuronide, taurocholate, glutarate, cAMP and uric acid. Estrone sulfate did not show any trans-stimulatory effects on either influx or efflux of [H-3]estrone sulfate via hOAT3. hOAT3 interacted with chemically heterogeneous anionic compounds, such as nonsteroidal anti-inflammatory drugs, diuretics, sulfobromophthalein, penicillin G, bile salts and tetraethyl ammonium bromide. The hOAT3 protein was shown to be localized in the basolateral membrane of renal proximal tubules and the hOAT3 gene was determined to be located on the human chromosome 11q12-q13.3 by fluorescent in situ hybridization analysis. These results suggest an important role of hOAT3 in the excretion/detoxification of endogenous and exogenous organic anions in the kidney.