真核表达载体pSMG的构建

CONSTRUCTION OF MAMMALIAN EXPRESSION VECTOR pSMG

In this paper,the construction process of a new kind of mammalian expression vector is described. Prokaryotic amplification vector pSP72A, Which was generated by deleting some single restriction endonuclease sites from pSP72 plasmid,was recombined with eukaryotic selecting marker gpt gene fragment to get the intermediate vector pSP72A-gpt.The final vector pSMG (pSP72A-gpt-MMTV)was then constructed by inserting 2.4kb initation ,splicing and termination region(derived from pMAMneo,including RSV and MMTV)for eukaryotic gene expressions into pSP72A-gpt. This vector can express exogenous genes cloned in its MCS (multiple cloning sites) in many kind of cultured cells and can be induced at high level expression by administration of glucocorticoid. Combining pSMG with other mammalian expression vectors containing different selecting markers Such as aminoglycoside phosphotransferase (neo or G418), dihydrofolate reductase (DHFR),adenosine deaminase (ADA) etc. ],two or more kinds of exogenous genes can be easily introduced into the same cell line and this will provide an useful tool for studying multiple genes interaction in eukaryotic cells.