Construction of an eukaryotic expression vector of SAG1 gene from Neospora caninum Jilin strain

Based on the SAG1 gene sequence of Neospora caninum in the GenBank(AF132217),a pair of primers containing Kozak sequence,initiation codon,termination codon,and BamHⅠ and EcoRⅠ enzyme digestion sites were designed.Using the recombinant plasmid pMD-18T-SAG1 containing SAG1 gene as template,the SAG1 gene was amplified by PCR.The PCR product was digested with BamHⅠand EcoRⅠ,and ligated into the digested eukaryotic expression vector pVAX1 with the same restriction endonuclease.Finally the recombinant plasmid named pVAX1-SAG1 was obtained.Further verification was performed by enzyme digestion,PCR amplification and sequencing.