蚕素Bombyxin A-4在家蚕杆状病毒表达系统中的表达与功能研究

Bombyxin is a 5 kDa brain peptide of the silkmoth Bonbyx nori, whose amino acid sequences have 40% identity with human insulin , belonging to the insulin peptide family. In this study, the target BA gene recombianted with B Chain and A Chain was obtained by SOE-PCR according to BombyxinA-4 ORF. The target BA gene was cloned into pGEX4T-1 to constuct expression vector pGEX4T-1-BA, then recombiant protein was expressed in E.coli Rosetta-gami(DE3)pLysS and purified, the purified protein immunize male New Zealand rabbit and the obtained antibody was used for detection. Then a Bombyxin protein gene (BombyxinA-4) sequence was obtained from silkworm cDNA library constructed by our laboratory. The target gene was recombined to Bacmid by Bac-to-Bac baculovirus expression system, transfected into BmN cells to generate recombinant baculovirus vBmBombyxinA-4. Then the silkworm pupae was infected with vBmBombyxinA-4. Results of Western blotting showed that the BombyxinA-4 could be expressed in silkworm pupa.The expression product can promote the growth of BmN cells. The normal pupa and the pupa infected by recombinant virus were made into the powder, to observe the effect of hypoglycemic effect on the experimental diabetes model mice.Results found that the pupa infected by recombinant virus can reduce blood sugar more significantly than the normal pupa. These results lay a foundation for how to development of new classes of hypoglycemic drugs and health products.