This vector system is designed for efficient analysis of mammalian promoters in mouse models utilizing the piggyBac transposon system. Typically, a putative promoter of interest is cloned into this vector, upstream of a LacZ reporter gene and the resulting construct is used to make transgenic mice. Expression of the LacZ reporter in transgenic embryos or adult mice can then be used as a readout of promoter activity. This vector system is useful for identifying promoter elements, determining tissue-specificity of promoters, comparing promoter variants, lineage-tracing and many other applications.
Our piggyBac transposon-based vector systems are highly effective for inserting foreign DNA into the host genome of mammalian cells. This system is technically simple, utilizing plasmids (rather than viral transduction) to permanently integrate your gene(s) of interest into the host genome.
The piggyBac system contains two vectors, both engineered as E. coli plasmids. One vector, referred to as the helper plasmid, encodes the transposase. The other vector, referred to as the transposon plasmid, contains two inverted terminal repeats (ITRs) bracketing the region to be transposed. The promoter sequence of interest is cloned into this region. When the helper and transposon plasmids are co-injected or co-transfected into target cells, the transposase produced from the helper would recognize the two ITRs on the transposon, and insert the flanked region including the two ITRs 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 after transposition.
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 introduced 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.
For further information about this vector system, please refer to the papers below.