家蚕小热休克蛋白BmHSP20.8基因的表达及功能研 究

Small heat shock protein (sHSP) is a family of proteins induced by heat treatment. We obtained a sequence from the cDNA library constructed by our laboratory. The sequence is 764 bp, contaning a full-length open reading frame(ORF) of 561 bp, encoding 186 amino acids of the analysis of homology, the results shows that the protein is a highly conservative silkworm small heat shock protein 20.8(BmHSP20.8). Firstly the ORF was ligated into the T7-based expression vector pET-28a(+), and are combination vector was constructed, secondly it was transformed to the BL21 for expression, and then the combined protein were purified By immunization of New Zealand rabbit with purified recombinant protein, the antiserum were generated. Finally, we carried out sub-cellular localization about BmHSP20.8 in the Bm5 and BmN ovarian cells under the normal and stimulated condition. The results show that after 3 hours of heat treatment of the BmHSP20.8, the protein migrated from the cytoplasm to cell membrance. It could improve the survival rate in the high temperate environment expressed by the E.coli, and after the heat treatment of 48℃, the survival rate is 4 times than the E.coli without the BmHSP20.8.