大鼠HSP27基因RNA干扰慢病毒载体的构建与鉴定

目的构建大鼠的热休克蛋白27(heat shock protein27,HSP27)RNA干扰慢病毒载体。方法设计并合成3对互补针对大鼠HSP27 mRNA的oligoDNA片段。磷酸化和退火后,分别克隆入pSUPER-basic质粒载体,获重组的pSU-PER-HSP27-oligoDNA。将其中表达shRNA的结构酶切插入慢病毒转移质粒pNL-IRES2-EGFP,产生pNL-HSP27-IRES2-EGFP,在293T细胞中与VSVG、pHelper包装产生慢病毒。48 h后收集上清液,离心过滤后进行病毒滴度测定。用构建正确的慢病毒质粒载体感染血管平滑肌细胞(vascularsmooth muscle cells,VSMCs),检测干扰效果。结果酶切和测序两种方法结果证明3种质粒载体的插入序列完全正确,慢病毒载体构建成功并获得相应的慢病毒,病毒悬液的滴度为3.12×109fu.L-1。重组慢病毒质粒pNL-HSP27-IRES2-EGFP-1的RNA干扰效率最高,为0.771。结论成功构建靶向大鼠HSP27基因RNAi慢病毒载体。为进一步研究HSP27功能和用慢病毒进行基因治疗奠定基础。

Construction and identification of a recombinant lentiviral vector harboring RNAi targeting rat HSP27 gene

Aim To construct the recombinant lentiviral RNA interference(RNAi) sequence targeting rat heat shock protein 27(HSP27)gene.Methods Three complementary DNA sequences targeting rat HSP27gene were designed and synthesized.After phosphorylation and annealing,these double strands DNA were cloned into vector pSUPER-basic respectively.Next the ds-oligo DNA which expressed short hairpin RNA(shRNA) was subcloned into lentiviral vector.The transfer plasmid(pNL-HSP27-IRES2-EGFP) was constructed and confirmed by electrophoresis and sequencing.Then the three plasmids of the lentiviral vector: pNL-HSP27-IRES2-EGFP,VSVG,and pHeler were cotransfected to 293T cells by Lipofectamine 2000 to package lentiviral particles.Forty eight hours later the supernatant was collected and the titer of virus was measured by detecting expression leve1 of enhanced green fluorescent protein(EGFP).Results The analysis using restriction endonuclease digestion and sequencing confirmed that the ds-oligo DNA was successfully inserted into the lentiviral vector.The recombinant lentivirus was harvested from 293T cells with a viral titer of 3.12 ×109 fu·L-1.Vascular smooth muscle cells(VSMCs) were infected by lentivirus,and the interfering efficiency was detected by RT-PCR and Western blot.The plasmid with the highest interfering efficiency was pNL-HSP27-IRES2-EGFP-1,and the interfering efficiency was 0.771.Conclusions The recombinant lentivirus containing RNAi targeting HSP27 gene has been successfully constructed,which lay a foundation for further study of the function and gene therapy of HSP27.