The pcDNA™ 3.4 TOPO® vector is a constitutive mammalian expression vector designed to deliver exceptionally high levels of transgene expression. It can be used in suspension-adapted cells, such as Expi293F™, FreeStyle™ 293-F, and FreeStyle™ CHO-S cells, for transient protein expression. The vector can also be used as a Geneticin®-selectable expression plasmid for engineering stable cell lines. The enhanced, full-length CMV promoter and other expression elements typically enable higher expression levels than pcDNA™ 3.1-, 3.2-, and 3.3-based expression constructs.

The pcDNA 3.4 TOPO® vector contains the following elements:

• Full length human cytomegalovirus (CMV) immediate-early promoter/enhancer for high level gene expression in a wide range of mammalian cells
• WPRE (woodchuck posttranscriptional regulatory element) downstream of the cloning site to enhance transcript expression
• TOPO® cloning site for rapid and efficient (>85%) cloning of Taq-amplified PCR products
• Neomycin resistance gene for selection of stable cell lines with Geneticin®
• pUC origin for high copy replication and maintenance of the plasmid in E. coli

The pcDNA3.4™ TOPO® TA Cloning Kit includes TOPO®-adapted plasmid vector, reagents for PCR cloning of your gene of choice into the vector, a sequencing primer for confirmation of insert orientation, and One Shot® TOP10 competent cells.