Cloning And Activity Analysis Of Promoter Of Sericin-1 Gene From Bombyx Mori And Study On Transgene.

The silk gland of Bombyx mori was an important organ for silk protein synthesizingand secreting with extremely power. It was feasible and hopeful for Bombyx mori silk glandbioreactor to express foreign medicinal protein safely and efficiently.The PigA3GFP transposon vector was constructed of several basic elements, i. e.,sericin-1 gene promoter of Bombyx mori, human insulin-like growth factor-1, thepolyadenylation acid signal of fibroin light-chain gene, the first intron of fibroin light-chaingene and the neo gene. The vector was further confirmed by PCR, enzyme digestion andsequencing analysis, and the results showed that all elements had been inserted into thePigA3GFP vector correctly. We have constructed PigA3GFP-hIGF-1. A in which the neogene was driven by SV40 promoter, and PigA3GFP-hIGF-1.B in which the neo gene wasdriven by IE-1 promoter.Then these transgenic vectors and the helper plasmid helper-PigA3 were transferredinto silkworm and BmN cells by sperm-mediated gene transfer and particle bombardmentgene transfer. We have abtained both silkworm and BmN cells, which could eradiate greenfluorescent. We ascertained that the most suitable concentration of G418 for BmN cell was700μg/mL～800μg/mL. We have screened transgenic BmN cells by antibiotics G418 at700μg/mL continuously for about one month. Now we have abtained high proportiontransgenic BmN cells with green fluorescent emission.