Construction Of A Bicistron Gene Transfer Body And The Impact Of Mar On Gene Integration And Expression

Due to the importance of transgenic safety in animals especially in farm animals, the present study was designed to construct marker-free expression vectors with regulation of MAR (matrix attachment regions). We have constructed a bicistron gene transfer body, that is, CAG-FSTN-IRES-AcGFP1-polyA, from the plasmid vector pCAG-FSTN-IRES-AcGFP1-polyA in which the bacteria sequence and resistant gene were deleted. We also constructed a bicistron gene transfer body with the addition of MARs on both side of the vector MAR-CAG-FSTN-IRES-AcGFPl-polyA-MAR. The transfection, integration and expression of these three vectors were analyzed. The results showed that the bicistron gene transfer body with no carrier frame sequence can be transfected, integrated and expressed normally; the MAR-bicistron gene transfer body had the highest integration efficiency and superior to other two groups in gene expressions.Furthermore, we screened the monoclonal cells derived from the three transgenic vectors, and obtained8strains of cells after transfection by the vector MAR-CAG-FSTN-IRES-AcGFP1-polyA-MAR. The gene integration and mRNA expression of the cells were investigated. In conclusion, the bicistron gene transfer body regulated by MAR is valued in the construction of marker-free with safety and high efficiency of transgenic vectors.