Figure 1. Schematic of the piggyBac ‘Tet-On’ vectors.

The PB Tet-On vectors contain a CAG enhancer/promoter that drives the expression of a 3^rd generation reverse tetracycline transactivator (rtTA3) coupled to an IRES and puromycin resistance gene. Immediately downstream is a minimal tetracycline response element (TRE) promoter that drives: (A) Apple fluorescent protein gene containing a short hairpin (hp) RNA in the 3′ UTR against the GFP gene (B) the GFP gene (C) a constitutively active form of the human AKT gene. EN = Enhancer, IR  =  Inverted Repeat, IRES  =  Internal Ribosome Entry Site, PA = polyA tail, Puro = puromycin resistance gene.