家蚕hsp70启动子的克隆及功能研究

Identification of Bombyx mori hsp70 Promoter and Its Function

该研究通过PCR的方法克隆得到家蚕热激蛋白70基因(Bombyx mori hsp70)的5'侧翼的两个长度分别为538 bp和305 bp的序列hsp70-538和hsp70-305。生物信息分析结果表明这两段序列在TATA序列的上游存在保守的热激元件HSE(heat shock element)CTnGAAnnTTCnAG。采用双荧光报告基因技术研究表明这两段序列在BmN细胞中都表现出热激活性,转基因家蚕实验证明hsp70-305在家蚕个体中也具有热激活性,可以认为这两个片段具有hsp70热激启动子特性。

We have got two fragments located in the upstream ofBombyx mori hsp70 gene, one was hsp70- 538 （538bp in length）, and the other was hsp70-305 （305bp） through the PCR amplification. By comparing analysis, these two fragments possess of the consensus sequence of riSE （heat shock element） associated with the heat shock genes of Drosophila： CTnGAAnnTTCnAG. Applying the technology of dual-luciferase vector, these two fragments can confer heat inducement in BmN cells. And the hsp70-538 fragment can induce more activity than hsp70-305 fragment. We also informed it by transgenic analysis in silkworm. Its activity was increased with the elevated tem- perature. The more exposure to 42℃, the more amount of target gene expression we got. So these two fragments can be considered as heat shock promoters.