油菜菌核病菌激发子基因SsXYN克隆及表达载体构建

以核盘菌菌株NGA₄提取的总RNA为模版，利用RT-PCR技术扩增获得SsXYN基因的全长cDNA片段，将其克隆到pMD19-T载体上，菌落PCR、酶切鉴定和cDNA测序结果表明成功克隆了核盘菌SsXYN基因。从pMD19-T : SsXYN载体上，用BamH I和Sal I 双酶切切下目的基因片段，将该基因片段连接到原核表达载体pET32a中。菌落PCR和酶切鉴定结果显示成功构建了表达载体pET32a : SsXYN。利用热击法将该重组表达载体导入大肠杆菌BL21，获得携带SsXYN基因的大肠杆菌菌株，为进一步研究激发子诱发植物抗病性机理奠定了基础。

Cloning of Sclerotinia sclerotiorum elicitor gene SsXYN and the expression vector construction

Total RNA was extracted from Sclerotinia sclerotiorum NGA₄ mycelia and used as the template to amplify the full length of cDNA of SsXYN gene by RT-PCR, and the gene fragment was subsequently cloned into pMD19-T vector. The results of bacterial colony PCR, enzyme analysis and sequencing analysis indicated that the S. sclerotiorum SsXYN gene was successfully cloned. SsXYN gene was digested completely from pMD19-T : SsXYN by BamH I and Sal I, and then was cloned into expression vector pET32a. The results of bacterial colony PCR and enzyme analysis showed the expression vector pET32a : SsXYN was successfully constructed. After that, the recombinant expression vector was carried into E.coli BL21 by heat-shock transformation, and the strain of E.coli BL21 carrying SsXYN gene was obtained. The study provides a basis for our understanding of the elicitor SsXYN downstream signaling pathway in plant immunity.