Taurine transporter (TauT) is a sodium‐ and chloride‐dependent transport carrier, and it plays a key role in the transportation of taurine. At present, the many functions of TauT in fish remain obscure. In this study, a cDNA clone for encoding a taurine transporter was isolated from Goldfish Carassius auratus. The nucleotide sequence predicted 625 amino acids with significant homology to the TauT gene of Zebrafish Danio rerio. Hydropathic analysis revealed stretches of hydrophobic amino acids that were indicative of 12 transmembrane domains that were similar to those proposed for other cloned TauT genes. The results of a reverse transcription polymerase chain reaction (RT‐PCR) analysis demonstrated that TauT broadly expressed in all of the selected tissues and developmental stages in Goldfish but with prominent differential expression levels. The expression of TauT in Goldfish has diurnal changes. The highest expression was at 1200 hours, and the lowest was at 2100 hours. Moreover, taurine treatments showed similar stimulatory effects on the expression of TauT in the intestines of Goldfish both in vitro and in vivo. Overall, these results may provide new insights into the regulation of TauT expression in fish, which has potential applications for improving fish dietary formulations.

中文翻译：

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金鱼中牛磺酸转运蛋白的分子表征和牛磺酸调控

牛磺酸转运蛋白（TauT）是依赖钠和氯的转运载体，在牛磺酸的转运中起关键作用。目前，TauT在鱼类中的许多功能仍然不清楚。在这项研究中，从金鱼Car鱼中分离出了一个编码牛磺酸转运蛋白的cDNA克隆。该核苷酸序列预测了625个氨基酸，与斑马鱼Danio rerio的TauT基因具有显着同源性。亲水性分析揭示了疏水性氨基酸的延伸，这些延伸指示了12个跨膜结构域，这些结构域与为其他克隆的TauT基因提出的结构域相似。逆转录聚合酶链反应（RT-PCR）分析的结果表明，TauT在金鱼的所有选定组织和发育阶段中广泛表达，但表达水平差异显着。TauT在金鱼中的表达有昼夜变化。最高表达时间为1200小时，最低表达时间为2100小时。此外，牛磺酸治疗在体外和体内均显示出对金鱼肠中TauT表达的类似刺激作用。总体而言，这些结果可能会为鱼类中TauT表达的调控提供新的见解，