红肉蜜柚 PDR 型转运蛋白基因的发掘及 CmPDR11-2 表达与耐草甘膦初步分析

基于红肉蜜柚 RNA-seq 数据库，筛选出 50 个 ABC 转运蛋白家族基因，其中包含 11 条 PDR 型基因。对11 条柚 PDR 基因进行命名和生物信息学分析。同源性分析结果表明：CmPDR11-2 编码的氨基酸序列与拟南芥中转运百草枯除草剂的 AtPDR11 基因同源性最高，达 69.25%，利用 RT-PCR 技术克隆得到 CmPDR11-2 的 ORF 序列。该序列长度为 4 371 bp，编码一个含有 1 456 个氨基酸的蛋白质，分子量 165.138 03 ku，该蛋白属于稳定的亲水性蛋白，无信号肽，具有 12 个跨膜结构，定位于细胞膜。实时荧光定量 PCR 结果表明，草甘膦除草剂胁迫处理条件下，1~15 d 处理组柚叶的 CmPDR11-2 基因相对表达量呈整体上升趋势，且均高于对照组，反应迅速且持久，这表明 CmPDR11-2 基因表达与红肉蜜柚耐草甘膦有关。

Discovery of PDR Transporter Gene in ‘Hongrou miyou’ and Preliminary Analysis of CmPDR11-2 Expressed with Glyphosate Tolerance

Based on the RNA-seq database of ‘Hongrou miyou’50 ABC transporter family genes were screened, including 11 PDR type genes. The nomenclature and bioinformatics analysis of 11 pomelo PDR genes were carried out. Homology analysis showed that the amino acid sequence encoded by CmPDR11-2 had the highest homology (69.25%)  with the AtPDR11 gene that transports paraquat herbicides in Arabidopsis. The ORF of PDR gene was named as  CmPDR11-2, which was a full-length of 4 371 bp, encoding a 1 456 amino acids with molecular weight 165.138 03 ku. The protein was stably hydrophilic, without signal peptide, with 12 transmembrane structure located in cell membrane. The results of real-time fluorescence quantitative PCR analysis showed that under the condition of glyphosate herbicide stress, the relative expression of CmPDR11-2 in the leaves treated with glyphosate for 1–15 days showed an overall upward trend, both of which were higher than the control, and the reaction was rapid and durable. This indicated that the expression of CmPDR11-2 gene was related to ‘Hong rou mi you’ glyphosate tolerance