pcDNA™ vectors enable high-level constitutive expression in a variety of mammalian cell lines. The pcDNA3.2/GW/D-TOPO vector offers the following key features:

• Cytomegalovirus (CMV) promoter for high-level expression
• Adaptable directional TOPO™ clones, allowing you to use Calibrate the polymerase and clone your PCR product in a specific orientation
• Neomycin resistance gene for stable selection
• C-terminal V5 tag for easy detection
• Ampicillin resistance gene and pUC starting point for selection and maintenance in E. coli

TOPO™ Cloning
Cloning your gene into an expression vector using restriction enzymes often forces you to destroy the final sequence of the insert ( Figure 1A), especially if there are no useful restriction sites near the gene for your coding sequence. This can result in suboptimal spacing of expression elements or the incorporation of unnatural amino acid residues, which may reduce your expression levels and/or result in the production of non-functional proteins.

TOPO™ cloning eliminates these potential expression issues, in addition to being a more efficient cloning method. TOPO™ expression vectors can insert the precise DNA sequence you require by PCR with appropriately designed primers. Your PCR product can be efficiently cloned into a topoisomerase I-activated expression vector in just 5 minutes. The resulting recombinant expression vector contains the exact DNA sequence without any non-coding regions (Figure 1B).

Many of our powerful expression vectors are available for one-step TOPO™ cloning and expression of PCR products. In addition, several expression vectors are now available for directional TOPO™ cloning, allowing you to use proofreading polymerases and clone PCR products in a specific orientation.