IDENTIFYING VIRULENCE FACTORS OF PATHOGENIC BACTERIA

鉴定致病菌的毒力因子

• 批准号: 6292984
• 负责人: JEFFREY H CHANG
• 金额: $ 3.48万
• 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/6292984
• 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P. maculicola race M6（Psm M6）和拟南芥属。Psm M6在缺乏Rpm 1的拟南芥生态型上是相容的。然而，它携带avrRpm 1，并且在表达Rpm 1的拟南芥上不相容。在植物生长后回收的Psm M6细胞的一小部分对所有测试的拟南芥生态型都是有毒的。在基因组中的重排，导致在一个Tn3插入avrRpm1和切除的质粒，被证明已经发生在这些现在的毒性细胞。这是Psm M6对植物信号的主动响应。我们感兴趣的是表征诱导基因Psm M6启动疾病在兼容的拟南芥植物和基因，响应于在植物中的信号，导致质粒切除。这些研究将为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致病菌的诱导毒力基因。IVET将适应于增加其能力，减少所需的劳动量，并仅检查发病机制的初始事件。所有必要的DNA结构都在我们手中，必要的修改也很容易，正在进行中。我们已经表明，该建议的几个方面是可行的。最后，我们提出了几个可能的方向，以追求在表征发病机制。一个完整的理解可能会导致创造新的，更强大的形式的抵抗植物病原细菌。