Construction and eukaryotic expression of recombinant plasmid ?hCG-CTP/pcDNA3 / 第三军医大学学报

ABSTRACT

Objective To clone and express the gene fragment of human chorionic gonadotrophin-? carboxyl terminal peptide (?hCG-CTP) and to explore the possibility of mouse immunocontraception with ?hCG-CTP gene fragment. Methods ?hCG-CTP gene fragment was chemically synthesized. ?hCG-CTP DNA fragment was digested with EcoRⅠ and BamHⅠ together, and then ligated to eukaryotic expression vector pcDNA3 which was also digested under the same condition. Product of ligation reaction was transformed into Escherichia coli DH5?. Recombinant plasmid pcDNA3/?hCG-CTP was then transfected into COS-7 cells with liposome. The expression of ?hCG-CTP gene fragment in mammalian animal cells was detected by immunohistochemistry. Results Double restriction enzyme digestion and subsequent sequencing of recombinant plasmids confirmed the correctness of the recombinant plasmids. Recombinant plasmid pcDNA3/?hCG-CTP was transfected into COS-7 cells with liposome, and transient expression of ?hCG-CTP protein was obtained. Conclusion Recombinant plasmid pcDNA3/?hCG-CTP which can express ?hCG-CTP gene in mammalian animal cells has been constructed correctly. The expressed product ?hCG-CTP can be recognized by antibody against ?hCG.