3种微生物诱导的家蚕attacin基因异常表达形式的研究

Abnormal Expression of Silkworm attacin Gene Induced by 3 Kinds of Microorganisms

[目的]研究家蚕抗菌肽attacin基因在不同诱导源诱导时的表达情况。[方法]应用3种外源微生物BmNPV、JM109以及农杆菌LBA4404对家蚕进行诱导,半定量PCR检测attacin基因在诱导后的家蚕血液和脂肪体的表达情况,对诱导表达产物进行克隆测序及进一步的分析。[结果]attacin基因在所有诱导后的脂肪体中均出现1条800 bp左右的特异表达条带,克隆测序(GenBank登录号:FJ373020)后发现其产生由正常表达形式的2个内含子未被剪接引起,且原序列第1内含子5′端的1个TGA终止密码子使得加长的特异表达序列翻译氨基酸时在此处终止,最终导致了attacin C末端结构的缺失。[结论]attacin基因有2种剪接形式,该研究对探明atta-cin基因在家蚕免疫中的作用具有参考价值。

[ Objective ] The aim of this research was to study the expression of silkworm attacin gene induced by some different microorganisms. [ Method] The silkworms were induced by 3 kinds of exogenous microorganisms, that is, BmNPV, JM109 and Agrobacterium LBA4404. After induction, the expression level in silkworm blood and fat body were detected by semi-quantitative PCR and subsequently the PCR products were cloned and sequenced for further analysis. [ Result] A specific band, about 800 bp, appeared in fat body of all induced silkworms. As indicated by the results of cloning and sequencing （ GenBank accession number： FJ373020）, the band was produced because the 2 introns existing in normal expression form were not spliced. Furthermore, when the extended expression sequence was translated into amino acids, the translation stopped earlier by the TGA stop eodon at the 5＇ end of the first intron of the original sequence, leading the loss of attaein C terminus. [Conclusion]There are two splicesomes of attacin gene, which has reference value to study the role of the attacin gene in silkworm immunity.