Figure 7. Schematic illustration of expression vectors containing different promoters.

The vectors were derived from the commercial pEGFP-C1 plasmid²⁴. A MAR sequence comprising a characteristic MAR motif from the human IFN-β gene was cloned into the multiple cloning site (MCS) of pEGFP-C1 resulting in the vector pEGFP-C1-MAR-promoter. The Neo/Kan gene is driven by dual promoters to confer kanamycin resistance in bacteria and G418 resistance in mammalian cells. AseI and NheI restriction sites are indicated. SV40, simian virus 40; ori, origin of replication; HSV, herpes simplex virus. The CMV promoter was excised and replaced by different promoters (RSV, UBC, SV40, PGK, and β-globin promoters) to produce the vectors used in this study.