茶树磷酸烯醇式丙酮酸转运子基因CsPPT的克隆与表达分析

以白叶1号为试验材料,通过RT-PCR和RACE技术克隆获得茶树磷酸烯醇式丙酮酸转运子基因CsPPT（GenBank登录号：KJ652972）。CsPPT完整ORF长度为1β227βbp,编码408个氨基酸,蛋白分子量为44.7βkDa,理论等电点为10.16;无信号肽位点,属于非分泌型蛋白;建立了茶树CsPPT蛋白的系统发育树;磷酸化修饰预测该蛋白质多肽链中共有26个磷酸化位点;TMHMM预测表明CsPPT蛋白为跨膜蛋白;亚细胞定位发现,CsPPT蛋白定位于叶绿体上,推测CsPPT蛋白可能定位于叶绿体膜上。荧光定量PCR结果表明CsPPT基因在茶树花中表达量最高,其次为芽、叶和嫩茎,根中最低。

Cloning and Expression Analysis of Phosphoenolpyruvate Transporter Gene CsPPT from Tea Plant (Camellia sinensis)

The open reading frame (ORF) ofCsPPT(GenBank accession number: KJ652972)fromCamellia sinensis‘Baiye1’was obtained using RT-PCR and RACE technology.ThededucedORF ofCsPPThas1227 nucleotides, encoding 408 amino acids. Bioinformatic analysis showed that the molecular weight of the predicted protein was 44.7 kDa,and the theoretic isoelectric point was 10.16.The predicted protein had no signal peptide, belonging to non-secretory protein. Poylogenetic treeofCsPPThadbeenbuilt. Phosphorylation predictionshowedthe whole protein polypeptidecontained26 phosphorylation sites.Subcellular localization ofCsPPTprotein displayed that it waslocatedinthe chloroplast. TMHMM analysisshowedthatCsPPTproteinbelongedtotransmembrane proteins. QRT-PCR analysis results showed that the expression ofCsPPThas obvious tissue specificity, which was higher in flower,followed by buds, leaves, and tender stems,but lower in roots.