拟南芥AtBT4对灰葡萄孢的抗性机制分析

【目的】揭示AtBT4在拟南芥抗灰葡萄孢中与SA、JA信号途经的相互关系。【方法】利用RT-PCR技术，检测用SA、SA类似物BTH、JA、ACC及灰葡萄孢处理拟南芥野生型Col-0后其AtBT4的表达情况；检测经SA和JA处理后拟南芥SA、JA途径相关突变体AtBT4的表达情况；并检测接种灰葡萄孢后拟南芥野生型Col-0、bt4突变体和回复突变体抗病相关基因的表达情况。【结果】JA处理和接种灰葡萄孢后，拟南芥野生型Col-0中AtBT4的表达明显增强。但经JA处理后，JA不敏感突变体jar1的AtBT4表达变化趋势与野生型明显不同，AtBT4的表达水平不受JA诱导。SA信号途径相关突变体eds5、sid2和npr1中AtBT4的表达明显低于野生型，但变化趋势与野生型基本一致。bt4突变体中抗病相关基因PR1、PR4、PDF1.2和BIK1的表达明显低于野生型和回复突变体。【结论】AtBT4的表达受JA和灰葡萄孢的诱导，AtBT4突变影响抗病相关基因PR1、PR4、PDF1.2和BIK1的表达，AtBT4可能通过SA、JA信号途径影响拟南芥对灰葡萄孢的抗性。

Mechanism Analysis of AtBT4 from Arabidopsis thaliana Against Botrytis cinerea

【Objective】The objective of this study is to reveal the interactions between AtBT4 gene and SA, JA signal pathways in Arabidopsis thaliana resistance to Botrytis cinerea.【Method】RT-PCR technology was used to analyze the expression of AtBT4 in Col-0 treated with SA, its analogues BTH, JA, ACC and B. cinerea, the expression of AtBT4 in various signals pathway mutants following SA or JA treatment and the expression of resistance-related genes in Col-0, bt4 and AtBT4 complemented plants. 【Result】The expression of AtBT4 in Col-0 treated with JA and B. cinerea was significantly enhanced. But no significant difference was observed in AtBT4 expression between the JA-insensitive jar1 mutants treated for 0 and 12 h with JA. The AtBT4 expression was significantly down-regulated in the eds5, sid2, and npr1 mutants compared with the Col-0 plants. Compared with the Col-0 and AtBT4 complemented plants, the expression of PR1, PR4, PDF1.2 and BIK1 genes was significantly down-regulated in the bt4 mutants. 【Conclusion】 The AtBT4 gene expression is induced by JA and B. cinerea and the AtBT4 gene deficiency alters expression of resistance-related genes, PR1, PR4, PDF1.2 and BIK1, suggesting the AtBT4 gene may be involved in the regulation of SA and JA singnal pathway to impact the resistance to B. cinerea in A. thaliana.