百合热激转录因子LlHSFA1调控百合耐热性的机理解析

项目名称： 百合热激转录因子LlHSFA1调控百合耐热性的机理解析

项目编号： No.31471904

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 农业科学

项目作者： 义鸣放

作者单位： 中国农业大学

项目金额： 83万元

中文摘要： 百合是花卉市场中重要的切花之一，在我国广泛栽培。其性喜凉爽湿润环境，多能耐受低温，但耐热性较差。夏季高温会造成百合切花和种球产量及品质的下降，是制约我国百合切花周年生产的主要限制因素。通过对拟南芥和番茄的研究表明，热激转录因子（Heat shock transcription factor,HSF）在调节植株耐热性上发挥重要作用，其中HSFA1是热激转录因子-热激蛋白途径中起主要作用的调节因子，在热激响应中表达量迅速升高，诱导下游多种逆境响应基因的表达，提高植株的耐热性。本项目拟从百合耐热品种'White Heaven'中克隆LlHSFA1基因，通过qRT-PCR检测其表达，亚细胞定位和转录活性分析其生化特征，拟南芥中过表达研究其耐热功能，通过基因芯片筛选下游调控基因并研究两者之间的相互关系，解析其调控百合耐热的机理。为采用基因工程技术改良百合品种的耐热性奠定理论基础和提供技术支撑。

中文关键词： 百合；热胁迫；热激转录因子；转录调控；耐热性

英文摘要： Lily holds a major market share in cut flower industry worldwide，which is widely cultivated in China. As for its characteristics, lilies are well adapted to cool and humid environments and most of them can even bear low temperature conditions; however, exposure to high temperature during summer may result in diminished cut-flower quality and in degeneration of the bulb, and which consequently restrict the year-round production of lilies as cut flowers. Heat shock transcription factors (HSFs) play an important role in thermotolerance of Arabidopsis and tomato, among which HSFA1 is the key transcription factor in the pathway of heat shock transcription factor-heat shock protein. HSFA1 which can be sharply induced by heat stress activates downstream stress-responsive genes to enhance plant thermotolerance. Here, we want to isolate homologous HSFA1 (LlHSFA1) from the thermotolerant cultivar 'White Heaven' of Lily, to detect its expression by qRT-PCR, to analyze its biochemical characteristics using subcellular localization and transactivation activity assay, to investigate its thermotolerant function through overexpression in Arabidopsis, to screen its target genes by gene microarray, and to analyze relationships between LlHSFA1 and these target genes. Taken together, these results can provide evidences for thermotolerant regulation of Lily. This work lays a foundation of theory and technique for improving thermotolerance of Lily via genetic engineering.

英文关键词： Lily;heat stress;heat shock transcription factor;transcription regulation;thermotolerance