Abstract：The present study is to construct prokaryotic expression vector of bovine Nanog gene and to induce its expression in E.coli (JM109). By means of reverse transcription –polymerase chain reaction(RT-PCR), cDNA of bovine Nanog gene was amplyfied from the tissues of fetal primodial genital ridges at age of six weeks. It was inserted into PMD18-T vector , then subcloned into vector pGEX-KG by gene recombination technique. After being confirmed by restriction enzyme digestion and sequencing, the recombinant plasmid pGEX-KG -Nanog was induced by IPTG（0.1-2m M/L）to express in JM109 at 25, 30, and 37℃. The results showed that（1）IPTG concentration and culture temperature exerted little impact on the expression yield of GST- Nanog fusion protein in JM109；(2) as indicated by western blotting , expressed efficiently in JM109 and reactivated with GST antibody, the fusion protein is about 60KD, which can be used to prepare polyclonal antibody of bovine Nanog gene.
