建立表达HCMVUL49基因的转基因小鼠,为抗病毒药物研究提供有效的实验动物模型。将UL49-GFP基因插入腺病毒穿梭质粒pDC316中,构建重组质粒pDC316-UL49-GFP,与腺病毒骨架质粒pBHGloxΔE1,3Cre通过脂质体介导共转染293细胞,重组产生腺病毒Ad-UL49-GFP,经PCR和Western blot鉴定正确后,大量扩增、纯化,制备高滴度重组腺病毒。纯化腺病毒经尾静脉注射感染小鼠,通过荧光定量PCR和Western blot方法,检测UL49基因在小鼠体内组织分布和表达时相。结果显示UL49基因在小鼠的心、肝、脾、肺、肾组织均有表达,并且表达量由高到低顺序依次是:肝、脾、肾、心、肺,在腺病毒感染第3天在各靶器官表达水平较高,此后逐渐下降,第14天时仅存在肝和脾中。表明表达UL49基因的小鼠模型构建成功。小鼠模型的成功建立为下一步筛选以UL49基因为靶的抗病毒药物奠定了基础。
Human cytomegalovirus (HCMV) is extremely species specific and does not replicate in experimental animal tissues.To overcome the problem and establish suitable animal models for studying antiviral strategies,the expression of HCMV UL49 gene was explored in mice.UL49-GFP gene was subcloned into the adenovirus shuttle plasmid pDC316,the products(pDC316-UL49-GFP)were co-transfected with helper plasmid pBHGloxE1,3Cre into HEK293 cell lines by liposome reagent,recombinant adenovirus(Ad-UL49-GFP) was generated and confirmed by PCR and Western blot.Ad-UL49-GFP was propagated in 293 cells and purified.The titer of viral stocks was determined by end-point dilution assay.The purified adenoviruses were delivered into mice via the tail vein injection.Fluorescence quantitative PCR and Western blot experiments were used to examine the tissue distribution and duration of UL49 gene expression.The results showed that the recombinant adenovirus were present in vivo.The expression level in tissues arranged in descending order was liver,spleen,kidney,heart and lung.3 days after injection,the liver,spleen,kidney,heart and lung expressed protein UL49 in high lever and then declined gradually.14 days after injection,UL49 protein expression was disappear in some organs except liver and spleen.In conclusion,transgene animal model carrying UL49 gene was successfully established.Therefore,the system may be suitable for selecting anti-HCMV drugs targeting UL49 gene.