日本血吸虫thioredoxin基因的克隆和表达

目的 结合分子生物学和生物信息学方法筛选鉴定日本血吸虫新基因。方法 从日本血吸虫(Schistosoma japonicum，大陆株)成虫cDNA库中获取表达序列标签(expressed sequence tag，EST)，用电子拼接的方法延伸序列，用NCBI提供的BLAETx程序和Genbank数据库进行同源性分析以筛选基因；设计特异性引物从日本血吸虫成虫mRNA中扩增筛选基因并预测和分析；扩增产物克隆到原核表达载体并表达。结果 筛选出日本血吸虫Thioredoxin全长基因并对其进行了序列分析，克隆全长cDNA至PET原核载体并表达成功。结论 结合EST、电子延伸和传统的分子生物学方法是高效筛选S.jiaponicum功能基因的有效策略。

The Cloning and Expression of Thioredoxin of S.Japonicum

Objective To screen and identify novel genes from Schistosoma japonicum. Methods Expressed sequence tag(EST) from the cDNA library of S.japonicum was elongated by in silicon elongation system. The elongated ESTs were analyzed by BLASTx to find similar sequence in Genbank. According to the information of elongated sequence, design special primers to amplify the full length sequence of interested gene, and then, predict the function, clone and express the gene. Result The full length gene encoding Sj thioredoxin was cloned into PET vector and the recombinant protein whose molecular was about 12000u was expressed as well as identified by SDS PAGE. Conclusion It prove a effective method for obtaining important functional genes to combine the approach of molecular biology and bioinformatics.