HPV16E7-HSP70融合基因原核表达质粒的构建和鉴定

目的构建HPV16E7-HSP70融合基因原核表达质粒,为进一步研究HPV16E7-HSP70融合蛋白抗喉癌免疫活性奠定基础。方法PCR扩增HPV16E7、HSP70并分别导入相应酶切位点;HPV16E7采用NheI和SacI接入原核表达载体pET28a得到pET28a-HPV16E7中间质粒;HSP70的PCR产物采用TA连接亚克隆到pGEM-Teasy载体;SalI和NotI双酶切后的HSP70片段和pET28a-HPV16E7线性质粒,经连接酶连接,采用PCR、DNA测序鉴定重组质粒;同时,重组质粒转入BL21(DE3)表达,采用IPTG诱导和WesternBlot进一步鉴定重组质粒的表达情况。结果重组质粒经PCR、DNA测序证实插入了HPV16E7-HSP70融合基因,且蛋白开放读码框与pET28a的6×His标签一致。通过IPTG诱导表达和WesternBlot证实融合蛋白可以在原核细菌中正确表达。结论成功构建pET28a-HPV16E7-HSP70重组原核表达质粒。

Construction and identification of a prokaryotic expression plasmid encoding HPV16E7-HSP70 fusion gene

OBJECTIVE To construct a prokaryotic expression plasmid encoding HPV16E7-HSP70 fusion gene for further study on the immunity of HPV16E7- HSP70 fusion protein against laryngeal carcinoma. METHODS HPV16E7 was PCR-amplified,digested by NheI and SacI,and ligated into pET28a. HSP70 was cloned into pGEMTeasy,then recut from the vector by SalI and NotI and ligated into pET28a-HPV16E7. PCR amplification, restrict enzyme digestion, DNA sequencing, IPTG induction and Western Blot were used to identify the recombinant plasmid. RESULTS Double digestion and PCR amplification of the recombinant plas- mid have shown that the size of the inserted fragment is as expected. Sequence analysis has demonstrated that the inserted fragment encodes for the HPV16E7- HSP70 fusion gene. IPTG induction and Western Blot have shown that the fusion protein is expressed suc- cessfully in the prokaryotic expression plasmid. CONCLUSION The recombinant prokaryotic expression plasmid pET28a-HPV16E7-HSP70 has been con- structed successfully.