胡杨肉质化关键基因PeXTH的启动子分析与转录调控研究

项目名称： 胡杨肉质化关键基因PeXTH的启动子分析与转录调控研究

项目编号： No.31500504

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 农业科学

项目作者： 韩彦莎

作者单位： 山西大学

项目金额： 20万元

中文摘要： 盐胁迫下组织发生肉质化是胡杨适应长期盐渍环境的重要方式。前期研究表明胡杨PeXTH基因在叶片肉质化过程中发挥重要作用，该基因受到盐胁迫诱导转录，但其转录调控的分子机制并不明确。我们前期从胡杨叶片中分离了PeXTH基因的启动子，通过生物信息学预测发现该启动子序列中包含多个盐诱导元件。在此基础上，本项目将采用5’端缺失法确定PeXTH启动子的盐胁迫响应关键区域；再经凝胶迁移分析和缺失突变实验鉴定该区域上的盐诱导元件；进一步利用酵母单杂交系统从胡杨叶片中分离与盐诱导元件相互作用的转录因子，分别通过荧光素酶活性分析和凝胶电泳迁移实验从体内和体外两个方面验证候选转录因子的作用，探讨盐胁迫诱导PeXTH基因转录的调控机理。本项目是前期研究的延续和深入，项目的开展有助于深入理解盐诱导胡杨组织肉质化发生的分子机制，对于丰富胡杨抗盐机理具有重要意义。

中文关键词： 胡杨；盐诱导肉质化；PeXTH；启动子；转录调控

英文摘要： Salt-induced tissue succulence is an important way of adaptation to a prolonged period of salinity stress in Populus euphratica. Our previous study demonstrated that PeXTH gene played crucial roles in the development of leaf succulence. In addition, salt treatment induced higher expression of the PeXTH gene in P. euphratica, while its transcriptional regulatory mechanism remains unknown. Salt-induced promoter of the PeXTH gene had been isolated in our previous study. Bioinformatics analysis showed that the promoter contained several salt-induced cis-elements. In this research, we intend to identify the critical salt-responsive region in the PeXTH promoter using 5’-sequence deletion method, and seek out salinity tolerance-related elements in the salt-responsive region by electrophoretic mobility shift assay and deletion mutation experiments. Then, using these elements as baits, we will isolate candidate transcription factors from P. euphratica leaves by yeast one-hybrid library screening system. At last, we verify the target ones with luciferase activity analysis and electrophoretic mobility shift assay in vivo and in vitro, respectively, which may help us to understand the transcriptional regulatory mechanisms of PeXTH. This study will contribute to a deeper understanding on the molecular mechanisms of salt-induced succulence, and enrich our knowledge in salt tolerance of P. euphratica.

英文关键词： Populus euphratica ;salt-induced succulence;PeXTH;promoter;transcriptional regulation