斯氏艾美耳球虫MIC5蛋白表达及生物信息学分析

Expression and bioinformatics analysis of MIC5 protein of Eimeria stiedai

为研究斯氏艾美耳球虫(Eimeria stiedai)的入侵及免疫机制,从基于Gateway技术构建的孢子化卵囊c DNA原核表达文库中扩增出了微线蛋白5(MIC5)部分基因序列,融合表达、纯化了相应的GST-MIC5蛋白多肽,并对该融合蛋白进行了生物信息学分析。结果显示,获得的MIC5基因部分序列长552 bp,与参考序列的同源性高达99%;经原核表达、纯化,获得大小约46 ku的融合蛋白,与预测相符;生物信息学分析发现,目的蛋白含3个由半胱氨酸序列构成的Apple结构域,揭示其与虫体黏附和入侵宿主细胞相关;诱导表达并纯化了与虫体黏附和入侵宿主细胞相关的MIC5部分蛋白。本研究为深入探讨斯氏艾美耳球虫MIC5蛋白的功能奠定了理论基础。

To investigate the invasion and immune mechanism of Eimeria Stiedai, an E. stiedai microneme 5 （ MIC5 ） sequence of 552 bp, which has 99% sequence homology with that of E. taneUa, was amplified from the prokaryotic cDNA expression library of the sporulated oo- cytes constructed using Gateway~ technology. Then the corresponding polypeptide was expressed and purified. The result showed that a fusion protein with an anticipated molecular weight of approximately 46 ku was obtained. Bioinformatics analysis revealed that the target protein con- tain Apple domains, including three cysteine residues that may be relevant with parasite adhesion and host cell invasion. Then the target frag- ment of E. stiedai MIC5 was induced to express and further purified. This study provides a basis for investigation of MIC5 function of E. stie- dai.