ObjectiveTo construct eukaryotic expression vector of pEGFP-N3-TFPI-2, and to provide the base of studying the function of TFPI-2 gene. MethodsExtraction of total RNA from placental tissue was extracted at first, and then reverse transcriptase synthesis of cDNA was carried out. The cDNA fragment of TFPI-2 gene which was obtained by real time PCR (RT-PCR) was inserted into eukaryotic expression vector of pEGFP-N3. After double digestion with XhoⅠand KpnⅠ, the recombinant vector of pEGFP-N3-TFPI-2 was identified in 1% agarose gel electrophoresis and was tested by the sequence analysis. Then, the recombinant vector of pEGFP-N3-TFPI-2 (transfection group) and vector of pEGFP-N3 (blank control group) were transfected into Top10 competent cells with LipofectamineTM 2000, but no transfection-related treatment was performed in cells of untransfection group. Western blot method was used to test the expression of TFPI-2 protein in cells of 3 groups. ResultsThe purity of total RNA which were analysis by agarose gel electrophoresis and spectrophotometry were fit for PCR. After coding of TFPI-2 gene fragment and eukaryotic expression vector of pEGFP-N3, the recombinant plasmid of pEGFP-N3-TFPI-2 were got double digestion with XhoⅠand KpnⅠ, and was identified in 1% agarose gel electrophoresis, of which showing that there were 2 specific amplification of strips at 708 bp and 4 700 bp. Result of sequence analysis confirmed that the size of recombinant vector was consistent with the theoretical value. Results of Western blot showed that the expression of TFPI-2 protein in transfection group (0.657 3±0.032 5) was higher than those of blank control group (0.301 7±0.028 7) and untransfection group (0.314 3±0.026 6), P < 0.01. ConclusionsThe eukaryotic expression vector of pEGFP-N3-TFPI-2 has been constructed successfully, which laiding the foundation for the analysis about function of TFPI-2 gene.