新疆小拟南芥NPR1基因对植物系统获得性抗性的影响

Effect of NPR1 Gene from Arabidopsis pumila on Plant Systemic Acquired Resistance

旨在研究小拟南芥NPR1基因的第三内含子对基因表达的影响。克隆出带有第三内含子的小拟南芥NPR1基因,构建诱导型植物表达载体并对拟南芥进行农杆菌遗传转化,经5 mmol/L外源水杨酸12 h诱导,利用Real-time PCR技术检测拟南芥病程相关蛋白的表达量。结果显示野生型拟南芥的NPR1、PR-1、PR-2、PR-5表达量高于转基因拟南芥;相对于野生型拟南芥,转基因拟南芥中SOD、POD酶活显著降低,而CAT酶活增加未达到显著水平。结果表明转入含有第三内含子的Ap.NPR1基因,转基因植株系统获得性抗性途径受到抑制,植株抗病性降低,说明第三内含子使得系统获得性抗性途径的基因表达受到抑制。

The aim is to study the effect of the third intron in Arabidopsis pumila＇s NPR1 gene on geneexpression. Arabidopsis pumila NPR1 gene was cloned with the third intron, plant expression vector of NPR1 gene was constructed and Arabidopsis thaliana were transformed via Agrobacterium tumefaciens. After beinginduced 12 h with 5 mmol/L exogenous salicylic acid, the expression of the pathogenesis-related protein wasdetected with Real-time PCR. The results showed that the expression of NPR1, PR-1, PR-2, PR-5 in wild-type Arabidopsis thaliana was higher than those of the transgenic Arabidopsis thaliana. Compared with wild-type Arabidopsis thaliana, the SOD and POD activities significantly decreased in transgenic Arabidopsis thaliana, while the CAT activity did not increase significantly. The results showed that when the gene Ap.NPR1 containing the third intron was transferred into Arabidopsis thaliana, the transgenic plants systemic acquiredresistance pathway was inhibited, and the plant disease resistance was reduced, which indicated that the thirdintron inhibited the gene expression of the systemic acquired resistance pathway.