HPV16 E7蛋白编码基因原核表达与鉴定

目的研究HPV16E7蛋白的生物学特性及其细胞转化机制，对HPV16E7蛋白原核表达质粒进行构建、表达和鉴定。方法以临床确诊的HPV16感染患者子宫颈细胞DNA为模板，采用PCR方法扩增HPV16E7基因，经BamH Ⅰ和Hind Ⅱ双酶切后插入相同酶切pET32a（＋）载体，转化JM109感受态细胞，并进行阳性克隆筛选。经IPTG对重组质粒进行蛋白诱导表达，SDS—PAGE和Western blot检测目标蛋白表达情况。结果成功构建了原核表达质粒pET32／E7，HPV16E7-TRX融合蛋白在BL21（DE3）菌株中高效表达，在1mmol／L IPTG、30℃诱导条件下融合蛋白表达量占菌体总蛋白的30％左右。结论pET32／E7原核表达质粒的构建、HPV16E7融合蛋白的表达为进一步深入研究HPV16E7蛋白的生物学特性及其致细胞转化的作用机制奠定了基础。

Prokaryotic Expression and Identification of Human Papillomavirus Type 16 E7 Protein Encoding Gene

OBJECTIVE: To construct the prokaryotic expression plasmid pET32/E7 and express the human papillomavirus type 16 E7 protein in E. coli. METHODS: HPV16 E7 gene was amplified by PCR. The amplified E7 fragment was inserted into the plasmid pET32a (+) that was digested with BamH I and Hind III. The recombinant plasmid pET32/E7 was transformed into E. coli JM109 which was selected with ampicillin. The positive clones containing recombinant plasmid pET32/E7 were verified by BamH I and Xho I digestion, and then sequenced. HPV16 E7-TRX recombinant protein expression in the E. coli BL21(ED3) was identified by SDS-PAGE and Western blot. RESULTS: The prokaryotic recombinant plasmid pET32/E7 was successfully constructed. The BL21(DE3) transformed recombinant plasmid pET32/E7 had expressed HPV16 E7-TRX recombinant protein effectively. Under the conditions of 1 mmol/L IPTG and 30 degrees C, the amount of HPV16 E7-TRX recombinant protein was about 30% of bacterial total proteins. CONCLUSION: The construction of the prokaryotic recombinant plasmid pET32/E7 and the successful expression of the recombinant protein HPV16 E7-TRX would strongly promote the research of the biological properties and the transformational mechanism of the HPV16 E7 protein on the specific cells.