茶树小分子量热激蛋白基因CsHSP17.2的克隆与表达分析  

Molecular cloning and expression analysis of low molecular weight heat shock protein gene CsHSP17.2 from Camellia sinensis

作　　者：王明乐[1] 朱旭君[1] 王伟东[1] 王炫清 林明露 黎星辉[1] 

机构地区：[1]南京农业大学茶叶科学研究所,江苏南京210095

出　　处：《南京农业大学学报》2015年第3期389-394,共6页Journal of Nanjing Agricultural University

基　　金：现代农业产业技术体系建设专项资金(CARS-23);江苏省科技支撑计划项目(BE2013426;BE2012440)

摘　　要：[目的]进一步了解茶树小分子量热激蛋白基因Cs HSP17.2在逆境胁迫条件下的分子生物学功能。[方法]利用RT-PCR技术从茶树‘迎霜’中克隆得到Cs HSP17.2基因,运用生物信息学软件分析其核苷酸和编码蛋白,通过Real-time PCR分析其表达模式。[结果]该基因开放阅读框长度为453 bp,编码150个氨基酸,蛋白质相对分子质量为17.2×103,理论等电点5.56;无信号肽位点,属于非分泌型蛋白;被定位于细胞质中。系统发育树分析表明,茶树Cs HSP17.2与水稻(Gen Bank登录号:P27777)和花生(ABC41131)的进化关系较近,属于小分子量热激蛋白基因家族第Ⅰ亚族。qRT-PCR分析发现,茶树Cs HSP17.2属于组成型基因;高温(38℃)处理1 h能显著提高Cs HSP17.2 mRNA的相对表达量(P<0.05);干旱(100 g·L-1PEG 6000)、高盐(200 mmol·L-1Na Cl)和外源脱落酸(200 mg·L-1ABA)处理条件下,该基因的转录水平均出现不同程度的上调。[结论]克隆得到茶树‘迎霜’小分子量热激蛋白基因Cs HSP17.2,其在花中表达量最高,且响应高温、干旱、高盐和外源脱落酸胁迫。[ Objectives ] To our knowledge,little is known about its molecular biological functions in Camellia sinensis. [ Methods ] The open reading frame （ORF）of CsHSP17.2 gene was isolated from C. sinensis＇Yingshuang＇. The obtained ORF sequence and deduced amino acid sequence was analysed with corresponding bioinformatic softwares. The real-time PCR was performed to study the expression profile of CsHSP 17.2 gene. [Resuhs]The ORF of CsHSP17.2 was 453 bp,encoding 150 amino acids. Bioinformatic analysis showed that the relative molecular weight of the predicted protein was 17.2 × 10^3 and the theoretic isoelectric point was 5.56. Besides, the predicted protein had no signal peptide, belonging to non-secretory protein. Subcellular localization indicated that CsHSP17.2 protein was distributed in cytoplasm. Poylogenetic tree analysis showed that CsHSP17. 2 had a close genetic relationship with Oryza sativa （GenBank accession No. ：P27777）and Arachis hypogaea （ABC41131 ） ,which was grouped to subfamily Class I. Real-time quantitative PCR found that CsHSP17.2 gene was expressed in various organs （roots, stems,leaves, buds ,flowers and fruits）, and also revealed that this gene could be significantly induced by high temperature （P〈0.05）. Besides, the relative transcript accumulation of CsHSPIZ2 was up-regulated by drought, high salinity and ABA treatment at certain levels. [Conclusions] CsHSP1Z 2 gene from C. sinensis ＇ Yingshuang＇ was isolated. This gene was up-regnlated by high temperature,which provided evidence for heat tolerence of tea plant.

关 键 词：茶 小分子量热激蛋白 CsHSP17.2 克隆 差异表达 实时荧光定量PCR 

分 类 号：S571.1[农业科学—茶叶生产加工]