CONSTRUCTION AND EXPRESSION OF THE PCDNA3.1(+)-MS EUKARYOTIC EXPRESSION PLASMID.

Objecticve:To construct and express the pcDNA3.1(+)-MS eukaryotic expression plasmid.Methods:Extracted DNA from M.Tuberculosis was amplified by PCR and the target gene we got was cloned into the unique HindⅢ and EcoR ⅰcloning sites of pcDNA3.1(+).Correct pcDNA3.1(+)-MS recombinant plasmid was identified by PCR,RE digestion and DNA sequencing .COS-7 cells were transfected with pcDNA3.1(+)-MS constructs by cationic liposom 48 hours later,mRNA of targets gene were detected by RT-PCR.Results:The accuracy of pcDNA3.1(+)-MS plasmid constructs was confirmed by a series of molecular biology techniques.Transfection of COS-7 cells with plasmid pcDNA3.1(+)-MS led to transient expression of MS proteins.Conclusion:The construction and expression of pcDNA3.1(+)-MS provided the possibility for investigating immunogenicity of the recombinant plasmid and preparing a new tuberculosis vaccine .