中文摘要：

[目的]为了研究拟南芥热激因子AtHsfA1a对热胁迫中抗坏血酸过氧化物酶（APX，EC1．11．1．7）的调控。[方法]以内源AtHsfA1a基因沉默的转基因拟南芥及野生型植株为材料，热胁迫后,采用分光光度法分析APX酶活性的变化,采用实时荧光定量PCR研究APX基因的表达水平，采用染色质免疫沉淀技术研究AtHsfA1a与APX基因启动子区的体内结合情况。[结果]在热胁迫下内源AtHsfA1a基因沉默植株中的APx的活性和mRNA的表达量均低于野生型，内源AtHsfA1a基因沉默的植株中未筛选出APX基因启动子区片断,而野生型则筛选出APX基因启动子区片断。[结论]AtHsfA1a对APX调控是直接的。该研究为进一步认识AtHsfA1a对植物耐逆境的作用及其应用提供理论依据，对揭示植物耐递境机理有重要意义。

英文摘要：

[Objective] This study was conducted to investigate the regulation of heat shock factor AtHsfA1a on ascorbate peroxidase under heat stress in Arabidopsis thaliana. [Method] After heat stress treatment on transgenetic A. thaliana with silenced endogenetic AtHsfA1a gene and wild A. thaliana plants as materials, the change in activity of APX enzyme was analyzed by spectrophotometry, the expression level of APX gene was investigated by real-time fluorescent quantitative PCR, and the binding condition of AtHsfAla with the promoter region of APX gene was analyzed by chromatin immunoprecipitation assay. [Result] The activity and mRNA level of APX in plants with silenced endogenetic AtHsfAla gene were higher than those in wild plants. Fragments of the promoter region of APX gene were not screened from the plants with silenced endogenetic AtHsfA1a gene, but found in wild plants. [Conclusion] This study provides a theoretical basis for the understanding of the important role of AtHsfAla in resistance to stress in plant, and is of great significance to the revealing of mechanism of resistance to stress in plant.