Regulation of Plant Gene Expression in Response to Infectionby Streptomyces Scabies

链霉菌是一种革兰氏阳性土壤细菌，是引起多种地下蔬菜赤霉病的病原菌。在侵染部位形成的赤霉病是由植物增殖的硫化物质组成的。生物体在块茎上形成典型的结痂病变的机制还不是很清楚，但可能涉及病原菌产生化合物，如紫杉素。这项建议的目的是开始研究植物基因表达的调控，以响应感染过程。为了鉴定这些植物调控基因，我们将从病斑发育的组织中构建一个cdna文库。将该文库与从非赤霉病植物组织制备的cDNA与从赤霉病组织制备的cDNA进行差异杂交，将用于鉴定在病变形成过程中特异表达的基因。未来的工作将集中在研究基因的调节和识别为应对感染而产生的基因产物。

Streptomyces scabies is a gram positive soil bacterium that is the causative organism for scab disease on a variety of underground vegetables. The scab lesion that forms at the site of infection is composed of a proliferation of suberinized material by the plant. The mechanism by which the organism elicits the formation of the typical scab lesion on the tuber is not well understood, but may involve the production of compounds such as thaxtomin by the pathogen. The goal of this proposal is to begin to study the regulation of expression of plant genes, in response to the infection process. In order to identify these plant regulated genes, a cDNA library will be prepared from tissue with developing scab lesions. Differential hybridization of the library with cDNAs prepared from non-scab plant tissue versus cDNAs prepared from scab tissue will be used to identify genes expressed specifically during lesion formation. Future work will be focused on studying the regulation of the genes and on the identification of the gene products that are made in response to infection.