茶树CsPIP2;7和CsPIP2;8基因的克隆及其对干旱胁迫的响应  

Cloning of CsPIP2;7 and CsPIP2;8 Genes in Tea Plant and Its Response to Drought Stress

作　　者：段梦莎 刘祥宏 万思卿 张永恒 贺镜元 刘焕 余有本[1] DUAN Meng-sha;LIU Xiang-hong;WAN Si-qing;ZHANG Yong-heng;HE Jing-yuan;LIU Huan;YU You-ben(College of Horticulture,Northwest A&F University,Shaanxi Yangling 712100)

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100

出　　处：《植物遗传资源学报》2020年第4期1009-1019,共11页Journal of Plant Genetic Resources

基　　金：国家现代农业产业技术体系(CARS-19);陕西省农业专项资金项目(SXNY2018-26);西北农林科技大学农业科技推广专项基金(TGZX2019-04)。

摘　　要：为了探究茶树水分胁迫中水通道蛋白的作用,以福鼎大白茶树(Camellia sinensis (L.)Kuntze‘Fuding Dabai’)为材料,克隆获得了2个水通道蛋白基因(AQPs,aquaporins),并分析了其在模拟干旱、外源施加ABA以及干旱和复水下的表达模式。氨基酸序列分析表明,2个水通道蛋白均含有MIP蛋白家族保守的信号序列SGGHINPAVT和2个高度保守的NPA(Asn-Pro-Ala)单元,均含有6个跨膜区。基于同源比对结果和细胞定位预测,将其归为质膜水通道蛋白(PIPs,plasma membrane intrinsic proteins)亚家族。实时荧光定量PCR的结果表明,2个CsPIPs的基因表达具有一定组织特异性,CsPIP2;7在叶中表达量最高,CsPIP2;8在花和叶中表达量较高。20%PEG模拟干旱胁迫处理后,CsPIP2;7转录水平显著下调,CsPIP2;8波动变化,24 h后轻微上调。外源施加ABA后,CsPIP2;7显著下调,而CsPIP2;8显著上调。此外,盆栽自然干旱及复水试验表明,2个水通道蛋白基因均在根部受到干旱胁迫的诱导上调表达,停灌24 d时转录水平达到最大值,CsPIP2;7和CsPIP2;8分别上调了7.13倍和3.68倍;停灌29 d时2个基因转录水平又下调,复水后下调或保持稳定。叶部表达模式与之不同,CsPIP2;7在缓慢干旱的过程中缓慢下调,复水后又显著上调;CsPIP2;8波动变化,与PEG处理时的表达模式相同,复水后下调。In order to investigate the effect of aquaporin in tea plant under water stress,two aquaporin genes(AQPs,aquaporins) were cloned from Camellia sinensis(L.)Kuntze‘Fuding Dabai’,and their expression patterns under simulated drought,exogenous application of ABA,natural drought and rehydration were analyzed. Amino acid sequence analysis showed that both aquaporins contained SGGHINPAVT,a conserved signal sequence of MIP protein family,and two highly conserved NPA(Asn-Pro-Ala) units,both of which contained six transmembrane regions. Based on the results of homologous alignment and the prediction of cell localization,they were assigned to the plasma membrane aquaporin(PIPs,plasma membrane intrinsic proteins) subfamily. The results of real-time fluorescence quantitative PCR showed that the gene expression of the two CsPIPs was tissue-specific,the expression level of CsPIP2;7 was the highest in leaves,and CsPIP2;8 was higher in flowers and leaves. After 20% PEG simulated drought stress,CsPIP2;7 was significantly down-regulated,CsPIP2;8 fluctuated,and was slightly up-regulated 24 hours later. After exogenous application of ABA,CsPIP2;7 was significantly down-regulated,while CsPIP2;8 was significantly up-regulated. In addition,experiments of natural drought and rehydration showed that the expression of the two aquaporin genes was up-regulated by drought stress and reached the maximum 24 days after irrigation stopped,CsPIP2;7 and CsPIP2;8 were up-regulated by 7.13 times and 3.68 times respectively,and the two genes were down-regulated 29 days after irrigation stopped,and were down-regulated or remained stable after rehydration. Different from the expression pattern of leaves,CsPIP2;7 decreased slowly in the process of slow drought and was up-regulated significantly after rehydration,and CsPIP2;8 fluctuated as with PEG treatment,but was down-regulated after rehydration.

关 键 词：茶树 水分胁迫 水通道蛋白 基因克隆 表达分析 干旱复水 

分 类 号：S571.1[农业科学—茶叶生产加工]