pTARGET™ Mammalian Expression Vector System Technical Manual

Literature # TM044

The pTARGET™ Mammalian Expression Vector System is a convenient system for cloning PCR products and for expression of cloned PCR products in mammalian cells. The vector is prepared by cutting the pTARGET™ Vector with EcoR V and adding a 3´ terminal thymidine to both ends. These single 3´-T overhangs at the insertion site greatly improve the efficiency of ligation of a PCR product into the plasmid in two ways. First the overhangs prevent recircularization of the vector; secondly they provide a compatible overhang for PCR products generated by certain thermostable polymerases. These polymerases often add a single deoxyadenosine in a template-independent fashion to the 3´-ends of amplified fragments. The pTARGET™ Vector also contains a modified version of the coding sequence of the α-peptide of β-galactosidase, allowing blue/white recombinant screening.