家蝇变应原Tropomyosin基因的克隆、序列分析及诱导表达

Cloning,Sequence Analysis and Prokaryotic Expression of Musca domestica Allergen Tropomyosin Gene

对家蝇变应原原肌球蛋白(Tropomyosin)基因进行同源克隆,序列分析;构建原核表达载体并在大肠杆菌中表达。从家蝇幼虫cDNA文库中筛选获得Tropomyosin基因。以该基因的cDNA文库质粒为模板,进行PCR扩增,获得家蝇Tropomyosin完整编码序列。运用生物信息学方法对该基因及其编码蛋白的基本理化性质、信号肽、二级结构、三级结构、抗原表位和亚细胞定位等方面进行预测和分析。构建pEASY-E1-Tropomyosin重组质粒,转化到大肠杆菌OrigamiB(DE3)中进行诱导表达。Tropomyosin基因ORF全长828 bp,编码275个氨基酸,理论分子量31.6 kD;等电点为4.65,具有Tropomyosin家族的蛋白保守结构域。成功构建重组原核表达pEASY-E1-Tropomyosin并诱导表达重组蛋白。

It was to probe into the homologous cloning of the Musca domestica allergen Tropomyosin gene, and then construct the prokaryotic expression vector which was expressed in Escherichia coli. Screening and isolation of Musca domestica Tropomyosin gene from Musca domestica cDNA library was carried out. The gene and encoded protein sequence of Tropomyosin was analyzed by bioinformatics methods , including general physical and chemical properties, signal peptide, secondary structure, tertiary structure, epitope and subcellular localization. Then plasmid pEASY-E1-Tropomysin were transformed into Escherichia coli BL21（DE3） competent cells for expression. The open reading frames of the Tropomyosin gene was 828 bp that encded a putative protein with 275 amino acids. The protein, with predicted molecular weight 31.6 kD and pI of 4.65, has the conserved Tropomyosin domain so belongs to Tropomyosin family. The result showed that the recombinant prokaryotic expression vector pEASY-E1-Tropomysin was successfully constructed and fusion protein was expressed in E. coli.