柔嫩艾美耳球虫杨凌株SO7基因的克隆表达与保护性试验

Cloning and expression of E.tenella YL strain SO7 gene and protective experiments

【目的】克隆鸡柔嫩艾美耳球虫SO7基因并进行原核表达,检测表达产物的免疫原性,为鸡球虫基因疫苗的制备奠定基础。【方法】以纯化的柔嫩艾美耳球虫杨凌(Eimeria tenella YL)株孢子化卵囊的总RNA为模板,用RT-PCR方法扩增出E.tenella YL株的SO7基因,对其测序后进行序列分析。将SO7基因克隆到表达载体pET-32a中,构建pET-SO7重组质粒,并在大肠埃希菌BL21中诱导表达出重组蛋白,将重组蛋白纯化后免疫雏鸡,评价其免疫效果。【结果】鸡柔嫩艾美耳球虫SO7基因序列的开放阅读框(ORF)为651个碱基,共编码217个氨基酸。E.tenella YL株SO7基因与E.tenella LS18株、E.tenella BJ株、E.tenella GD株SO7基因ORF区序列相似性分别为99.1%,98.6%和99.1%,其氨基酸序列相似性分别为99.1%,98.6%和99.1%。SDS-PAGE分析表明,表达产物成功地表达出了分子质量为45ku的融合蛋白。各种抗球虫指标的测定结果显示,该蛋白对球虫感染鸡体具有一定的保护性。【结论】SO7基因具有很强的保守性,各虫株之间差异不大;重组蛋白具有一定的保护效果,适合用来制备基因疫苗。

【Objective】The research studied cloning and expression of E.tenella YL strain SO7 gene.【Method】E.tenella SO7 gene was cloned fromE.tenellasporulated oocysts sporozoites by RT-PCR.The recombinant expression plasmid pET-SO7 was constructed and expressed in BL21 strain of E.coli.The product was analysed by SDS-PAGE.Then,recombinant proteins were used in chickens infected with E.tenella YL strain to judge the protective rate of the recombined proteins.【Result】Sequence analysis suggested that the ORF of SO7 gene...