摘要:Objective To establish a zebrafish model for liver-specific expression of HCV non-structural protein NS5A, and to explore the effects of HCV NS5A on liver pathological marker genes in vivo.Methods Liver-specific gene expression regulating element zebrafish fatty acid binding protein enhancer (eFABP) sequence and HCV NS5A was cloned. By ligating the eFABP, CMV promoter, NS5A, the IRES of encephalomyocarditis virus (EMCV) and DsRed in turn, a liver-specific gene expression vector pFC-5AiR was constructed. Reporter gene DsRed was detected in Huh7 cells transfected with pFC-5AiR. The linearized vector was subsequently microinjected into zebrafish embryos. Liver-specific expression of pFC-5AiR was detected by observation under fluorescence microscopy and whole mount in situ hybridization methods. Moreover, the transcriptional and translational levels of NS5A were investigated by RT-PCR and western blot. Finally, expression level of some liver pathology associated genes was investigated by RT-PCR.Results Cell transfection results showed that red fluorescent protein gene DsRed in pFC-5AiR is able to be expressed in Huh7 cells. After microinjection of the vector into zebrafish embryos, red fluorescence was observed to be located in the zebrafish liver under fluorescent microscopy. RT-PCR and western blot results indicated that NS5A is able to be expressed in zebrafish. In situ hybridization results further confirmed that the expression of NS5A in zebrafish liver. In addition, some pathological marker genes, such as Adiponectin, Argsyn, LDLR, TGF-β and HMGR etc., were up-regulated in response to HCV NS5A expression, suggesting that NS5A may be involved in liver lipid metabolism disorder and fibrosis.Conclusion A zebrafish model for HCV NS5A expression in liver has been successfully established. Preliminary investigation shows that HCV NS5A expression in vivo is associated with aberrant genes expression involved in liver pathological process. This model can be used to study the pathological role of HCV NS5A in vivo.%目的 建立HCV非结构蛋白NS5A基因在斑马鱼肝脏特异表达的模型,研究HCV NS5A的体内作用机制并初步探讨HCV NS5A对肝病理标志基因表达的影响.方法 克隆肝基因表达调控序列——斑马鱼脂肪酸结合蛋白基因增强子序列(eFABP)和HCV非结构蛋白基因NS5A序列,利用CMV启动子序列,构建HCV NS5A基因和报告基因绿色荧光蛋白基因eGFP在肝脏共表达的基因构件pFC-5AiR.经细胞转染实验验证所建构件的报告基因DsRed表达红色荧光蛋白后,将该基因构件线性化并经显微注射导入斑马鱼胚胎;通过荧光显微镜观察和整体原位杂交技术对目的基因NSSA的表达进行定位,验证其肝脏特异性表达.采用RT-PCR方法和western blot方法对HCV NS5A基因的转录和翻译水平进行检测;并检测肝脏病理相关的标志基因的转录水平变化.结果 细胞转染实验证明基因构件pFC-5AiR的报告基因DsRed能够在肝癌细胞Huh7中表达;斑马鱼胚胎注射该基因构件后在肝脏能够观察到红色荧光蛋白基因DsRed的表达;RT-PCR和western blot结果显示HCV基因NS5A能够在斑马鱼体内正确表达;原位杂交结果进一步证明了NS5A的表达集中在斑马鱼肝脏内.进一步RT-PCR检测表明HCV NS5A在斑马鱼体内的表达可导致一些肝代谢和纤维化相关基因的上调,如Adiponectin、LDLR、Argsyn、TGF-β和HMGR等,推测NS5A在肝脏脂肪病变和纤维化中具有一定作用.结论 成功建立了斑马鱼肝脏表达HCV NS5A的模型;初步数据表明HCV NS5A在斑马鱼体内的表达与部分肝代谢和纤维化标志基因的异常表达相关;该模型可以用于HCV NS5A的体内病理机制的研究.