中国生物工程杂志

Based on the EIAV vector pcPPTWPRE, the plasmids pWCAGP0.8 containing part of the chicken β-actin intron 1 and pWCAGP1.6 containing the full intron were constructed by restriction enzyme digestion.Then the EIAV gene transfer vectors pWCAGP0.8, pWCAGP1.6 and pcPPTWCAG which were previously constructed without the chicken β-actin intron 1 were transfected into HEK293 cells and DF-1 cells using Calcium Phosphate Transfection Kit, respectively. The cells were investigated under fluorescence microscope at 12, 24, 36 and 48h after transfection. Flow-cytometric analysis was carried out at 48h. Results showed that the pcPPTWCAG had the equal EGFP expression level with pWCAGP0.8, while both of them could express EGFP much more efficiently than pWCAGP1.6 in HEK293 cells. In DF-1 cells, the pcPPTWCAG could express the EGFP a little more efficiently than pWCAGP0.8, while both of them could express EGFP much more efficiently than pWCAGP1.6. Results indicated that the chicken β-actin intron 1 could decrease, rather than increase the EGFP expression of EIAV vectors in both HEK293 cells and DF-1 cells.