Chen L, Ortiz-Lopez A, Jung A, Bush D R
Program in Physiological and Molecular Plant Biology, Urbana, Illinois 61801.
Plant Physiol. 2001 Apr;125(4):1813-20. doi: 10.1104/pp.125.4.1813.
A new amino acid transporter was identified from the Arabidopsis expressed sequence tag cDNAs by expressing the cDNA in a yeast amino acid transport mutant. Transport analysis of the expressed protein in yeast showed that it transports aromatic and neutral amino acids, as well as arginine. This transporter (ANT1, aromatic and neutral transporter) also transports indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid. The cDNA is 1.6 kb in length with an open reading frame that codes for a protein with 432 amino acids and a calculated molecular mass of 50 kD. Hydropathy analysis showed ANT1 is an integral membrane protein with 11 putative membrane-spanning domains. Southern analysis and a BLAST search of the Arabidopsis genome database suggests that ANT1 is part of a small gene family containing at least five members. Phylogenetic comparisons with other known amino acid transporters in plants suggests that ANT1 represents a new class of amino acid transporter. RNA gel-blot analysis showed that this transporter is expressed in all organs with highest abundance in flowers and cauline leaves.
通过在酵母氨基酸转运突变体中表达拟南芥表达序列标签cDNA，鉴定出一种新的氨基酸转运蛋白。对酵母中表达的蛋白进行转运分析表明，它能转运芳香族和中性氨基酸以及精氨酸。这种转运蛋白（ANT1，芳香族和中性氨基酸转运蛋白）还能转运吲哚 - 3 - 乙酸和2,4 - 二氯苯氧乙酸。该cDNA长度为1.6 kb，具有一个开放阅读框，编码一个含有432个氨基酸、计算分子量为50 kD的蛋白。亲水性分析表明ANT1是一种具有11个推定跨膜结构域的整合膜蛋白。对拟南芥基因组数据库的Southern分析和BLAST搜索表明，ANT1是一个至少包含五个成员的小基因家族的一部分。与植物中其他已知氨基酸转运蛋白的系统发育比较表明，ANT1代表了一类新的氨基酸转运蛋白。RNA凝胶印迹分析表明，这种转运蛋白在所有器官中均有表达，在花和茎生叶中丰度最高。
