Our piggyBac vector system is highly effective for inserting foreign DNA into the host genome of mammalian cells. This system is technically simple, utilizing plasmid transfection (rather than viral transduction) to permanently integrate your gene(s) of interest into the host genome.
The system is derived from the piggyBac transposon, which is originally isolated from the cabbage looper (Trichoplusia ni; a moth species). Based on sequence homology, the piggyBac transposon was found to belong to a class of transposons common to many animals.
The piggyBac system contains two vectors, both engineered as E. coli plasmids. One vector, referred to as the helper PBase plasmid, encodes the transposase. The other vector, referred to as the transposon plasmid, contains two terminal repeats (TRs) bracketing the region to be transposed. The gene to be delivered into host cells is cloned into this region.
When the PBase vector and the piggyBac transposon vector are co-transfected into target cells, the transposase produced from the helper would recognize the two TRs on the transposon, and insert the flanked region including the two TRs into the host genome. Insertion typically occurs at host chromosomal sites that contain the TTAA sequence, which is duplicated on the two flanks of the integrated fragment.
PiggyBac is a class II transposon, meaning that it moves in a cut-and-paste manner, hopping from place to place without leaving copies behind. (In contrast, class I transposons move in a copy-and-paste manner.) Because the helper plasmid is only transiently transfected into host cells, it will get lost over time. With the loss of the helper plasmid, the integration of the transposon in the genome of host cells becomes permanent. If these cells are transfected with the helper plasmid again, the transposon could get excised from the genome of some cells, footprint free.
For further information about this vector system, please refer to the papers below.