含双病原物诱导启动子植物安全表达载体的构建

 本研究用来自烟草的具有高度病原物特异性的两个诱导启动子EAS4和hsr203J,串联驱动GUS基因的表达,同时考虑到转基因植物的安全性,引入双边界序列,构建了含双病原物诱导启动子的植物安全表达载体。将表达载体转化烟草获得转基因植株。分析显示,在正常生长情况下转基因烟草检测不到GUS活性,或活性极低;而受疫霉激发子parasiticein、Phytophthora nicotianea0]的孢子悬浮液和Ralstonia solanacarum的菌悬液诱导后,转基因烟草叶片中可检测到明显的GUS活性。结果表明,构建的植物表达载体所含双病原物诱导启动子均具有良好的诱导活性,可用于植物遗传转化。

Construct of plant safety expression vector harboring two pathogen inducible promoters

Plants are often subjected to infections of various pathogens in their whole life. This is so called complex infections. Complex infections of pathogens are challenged for genetic engineering of plant disease resistance. In this study a plant safety expression vector was constructed. The vector harbored twin T-DNAs and the selective marker gene NPTⅡ expression cassette was separated in different T-DNAs from the GUS expre-ssion cassette in which two highly pathogen-specific inducible promoters, EAS4 and hsr203J, were used to drive report gene. Transgenic plants were obtained from the transformation of tobacco by the vector. The GUS activity could not be detected or was very low in the transgenic tobacco plants without induction. Whereas the GUS activity was much higher when the plants were treated with parasiticein or inoculated with spore suspensions of Phytophthora nicotianea0] and Ralstonia solanacarum. The results showed that the two promoters in transgenic plants were highly pathogen-specific inducible and could be used as a powerful tool for genetic engineering in plant disease resistance.