ESB1基因在植物对灰霉病抗性中的分子机制研究

Botrytis cinerea causes severe disease both in the field and in postharvest situations, resulting in enormous economic losses. To seek resistant genes, and grow disease resistant crops is the most effective and environment-friendly strategy for protecting the crop from grey mould disease. In our previous research, we screened mutants from a T-DNA insertion-mutagenized Arabidopsis population. A mutant with enhanced susceptibility to Botrytis was identified, named esb1. The further analysis showed that esb1 mutant was not only susceptibility to Botryti stress, but also impaired tolerance to water deficit and increased salinity. The insertion of T-DNA suppresses the expression of ESB1 gene in esb1 mutant according to RT-PCR analysis. DNA sequence analysis indicates that ESB1 encods a hypothetical protein. And its function remains unclear. The result of transformation ESB1 gene to the mutant showed that ESB1 gene could recovery its susceptibility to Botrytis mutant phenotype into the phenotype same as the wild type. This result showed that ESB1 gene is essential for resistance to gray mould disease. Those mentioned results indicated that ESB1 gene probably involved in signal transduction of plant response to biotic and abiotic stresses. And this project plan to conduct the following research based on the above experimental data: 1. Analysis the expressional pattern of ESB1 gene, in order to determine the period and location of ESB1 gene working during interaction between plant and pathogen. 2. Explore the panorama of how ESB1 gene mediates expression of related genes in response to infection of Botrytis. 3. Find the signaling pathway components which interaction with ESB1 gene and identifying which pathway that ESB1 involved. Our work will provide insights into the molecular mechanisms of Arabidopsis defense against pathogen and facilitates the development of resistant crops to control this devastating pathogen.

灰霉菌对农作物生长和储运均有重大危害，寻找具有抗性的基因并培育抗性作物甚为重要。本项目前期研究已从拟南芥的T-DNA插入群体中筛选到一个对灰霉菌及干旱和盐渍均敏感的突变体，命名为esb1。RT-PCR分析表明T-DNA插入突变导致ESB1基因转录抑制。DNA序列分析表明该基因编码一个功能未知的推定蛋白。导入野生型基因，能够互补灰霉病敏感的突变性状，证明该基因是灰霉病抗性所必需的。前期研究结果表明ESB1基因可能参与了植物对生物和非生物胁迫反应的信号转导。本项目拟在上述基础上，利用分子生物学和生理学技术开展以下研究：1.分析该基因的表达模式，确定该基因在植物与灰霉菌互作中发挥作用的时期和部位。2.研究该基因对灰霉菌反应相关基因表达调控的全景图像。3.寻找与其互作的其它组分，探索其参与的信号转导途径。本研究能深入认识ESB1基因调控抗灰霉病的分子机制，对于利用基因工程提高作物抗病性具有意义。