IDENTIFYING VIRULENCE FACTORS OF PATHOGENIC BACTERIA

鉴定致病菌的毒力因子

• 批准号: 6489918
• 负责人: JEFFREY H CHANG
• 金额: $ 4.42万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6489918
• 关键词: Arabidopsis; Pseudomonas; bacterial cytopathogenic effect; gene expression; genetic manipulation; genetic techniques; host organism interaction; microorganism interaction; molecular cloning; nucleic acid sequence; pathologic process; plant diseases; plant genetics; restriction mapping; southern blotting; technology /technique development; transfection /expression vector

We propose to use IVET to investigate the interaction between P. syringae pv. maculicola race M6 (Psm M6) and Arabidopsis. Psm M6 is compatible on ecotypes of Arabidopsis lacking Rpm1. However, it carries avrRpm1 and is incompatible on Arabidopsis expressing Rpm1. A small percentage of Psm M6 cells recovered after growth in planta are virulent on all tested ecotypes of Arabidopsis. Rearrangements in the genome, resulting in a Tn3 insertion into avrRpm1 and an excision of a plasmid, were demonstrated to have occurred in these now virulent cells. This is an active response by Psm M6 to signals of the plant. We are interested in characterizing the induced genes of Psm M6 for initiating disease in compatible Arabidopsis plants and the genes that respond to in planta signals which lead to the plasmid excision. These studies will provide a comprehensive analysis of how Psm M6 initiates disease in Arabidopsis. IVET is a promoter-trapping technique that has been used successfully to identify induced virulence genes of many pathogenic bacteria. IVET will be adapted to increase its capability, reduce the amount of labor required, and examine only the initial events of pathogenesis. All necessary DNA constructs are in our possession and necessary modifications are facile and in progress. We have already demonstrated that several facets of the proposal are feasible. Finally, we present several possible directions to pursue in characterizing the mechanisms of pathogenesis. A complete understanding could lead to the creation of novel, more robust forms of resistance against phytopathogenic bacteria.

我们建议使用IVET来研究丁香疫霉之间的相互作用。黑斑病小种M6(PSM M6)和拟南芥。PSM M6与缺乏Rpm1的拟南芥的生态型亲和。然而，它携带avrRpm1，与表达Rpm1的拟南芥不亲和。在植物中生长后恢复的一小部分PSM M6细胞对所有测试的拟南芥生态型都是毒力的。基因组中的重排，导致Tn3插入avrRpm1并切除了一个质粒，被证明发生在这些现在的毒力细胞中。这是PSM M6对植物信号的积极反应。我们感兴趣的是鉴定PSM M6在拟南芥亲和植物中引发病害的诱导基因，以及对导致质粒切除的植物信号做出反应的基因。这些研究将对PSM M6如何在拟南芥中引发疾病提供全面的分析。IVET是一种启动子捕获技术，已成功地用于鉴定许多病原菌的诱导毒力基因。IVET将被调整以增加其能力，减少所需的劳动量，并仅检查发病的初始事件。所有必要的DNA构建都在我们手中，必要的修改很容易，而且正在进行中。我们已经证明，该提案的几个方面是可行的。最后，我们提出了几个可能的方向，以表征发病机制。完全了解可能会导致对植物病原菌产生新的、更强大的抗性形式。