Fig. 3
Structures of the transformation vectors pFeIFN-α15/MSG1.1 MG and pIM1. Each vector consisted of expression units for a selection marker and the recombinant protein, located between the right and left arms of piggyBac. The selection marker MGFP was placed between the 3xP3 promoter (P3xP3) and the SV40 polyA signal sequence (SV40 polyA) and between the B. mori actin promoter (PA3) and SV40 polyA in pFeIFNα-15/MSG1.1MG and pIM1 vectors, respectively. The cDNA of FeIFN-α15 on pFeIFN-α15/MSG1.1 MG was placed between the ser1 promoter (Pser1) and the fibroin L-chain polyA signal sequence (fibL polyA). The BmNPV hr3 enhancer was located upstream of Pser1, and the IE1 trans activator gene (ie1) on pIM1 was placed between Pser1 and fibL polyA