Abstract：The idea and the elements for semliki frost virus(SFV) RNA replicon, a kind of new generation vector, come from the Alphavirus genus. It was designed to overcome the poor efficacy of some current DNA-based and RNA-based vector. Genes coding for viral replicases are reserved while genes coding for structure proteins are replaced by foreign gene in RNA replicon. High level replication of RNA and expression of foreign gene in cytoplasm are regulated by the replicases.To evaluate the effects of the SFV RNA replicon on the efficiency of gene expression, LacZ gene was inserted into pIRES-neo which digested by BamHⅠand dephosphorylated by shrimp alkaline phosphatase, creating pIRES-neo-LacZ in the present study. RNA replicon vector pCMV-rep-LacZ and two conventional CMV promoter-based vector pLNCX-LacZ, pIRES-neo-LacZ were transfected by Lipofectin to prepared 293 cells respectively. RNA replicon vector pCMV-Rep-GHRH and two conventional CMV promoter-based vector pCDNA3.1(+)-GHRH, pIRES-neo-GHRH were transfected by Lipofectin to prepared 293.
