Tate S S, Yan N, Udenfriend S
Department of Biochemistry, Cornell University Medical College, New York, NY 10021.
Proc Natl Acad Sci U S A. 1992 Jan 1;89(1):1-5. doi: 10.1073/pnas.89.1.1.
Uptake of long-chain and aromatic neutral amino acids into cells is known to be catalyzed by the Na(+)-independent system L transporter, which is ubiquitous in animal cells and tissues. We have used a Xenopus oocyte expression system to clone the cDNA of a system L transporter from a rat kidney cDNA library. The 2.3-kilobase cDNA codes for a protein of 683 amino acids. The transporter has four putative membrane-spanning domains and bears no sequence or structural homology to any known animal or bacterial transporter. When transcribed and expressed in Xenopus oocytes, the transporter exhibits many, but not all, of the characteristics of L-system transporters, suggesting that this represents one of several related L-system transporters.
已知长链和芳香族中性氨基酸进入细胞是由不依赖钠离子的L系统转运体催化的，该转运体在动物细胞和组织中普遍存在。我们利用非洲爪蟾卵母细胞表达系统从大鼠肾脏cDNA文库中克隆了一种L系统转运体的cDNA。这个2.3千碱基的cDNA编码一个由683个氨基酸组成的蛋白质。该转运体有四个假定的跨膜结构域，与任何已知的动物或细菌转运体没有序列或结构同源性。当在非洲爪蟾卵母细胞中转录并表达时，该转运体表现出L系统转运体的许多但并非全部特征，这表明它代表了几种相关L系统转运体之一。
