家蝇幼虫抗菌肽Defensins基因的克隆与序列分析

目的：克隆家蝇幼虫的抗菌肽defensins基因并对其进行序列分析。方法：提取家蝇幼虫总RNA，根据家蝇成虫defensins基因cDNA序列设计一对引物，RT-PCR扩增目的基因片段，T-A克隆后测序，应用相关生物信息学软件对该序列进行分析。结果：RT—PCR扩增出一条约310bp的目的片段，序列分析表明，其与家蝇成虫防御素基因同源性高达97％，核酸序列变异主要发生在信号肽区域。结论：成功克隆及分析了家蝇幼虫防御素基因全长编码区cDNA序列，为其下一步的重组表达和生物活性研究奠定了基础。

Cloning and Sequence Analysis of the Defensins Gene from Musua domestica Larva

Objective To clone and sequence analysis the defensins genes from Musca domestica larva. Methods Total RNA was extracted from Musca domestica larva. The PCR was carried out, and the product of PCR were puified and cloned into plasmid T vector. The recombinant plasmid was sequenced and analyzed. Results The amplified products from Musca domestica larva were about 310bp. The sequence analysis showed that the amplified fragment from Musca domestic larva had a high homology compared with the published defensins sequence from Musca domestica.There has a single nucleotide variation at signal peptide region. Conclusions The defensins cDNA of Musca domestica larva have been cloned successfully.This will lay the foundation for the research of expression of the recombinant defensins and its antibiotic activity.