中国寄生虫学与寄生虫病杂志 ›› 2007, Vol. 25 ›› Issue (4): 10-319.

• 实验研究 • 上一篇    下一篇

伯氏疟原虫pbmag-1基因片段克隆及原核表达优化

高宇辉; 王恒   

  1. 中国医学科学院中国协和医科大学基础医学研究所病原系分子寄生虫学实验室, 北京 100005
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2007-08-30 发布日期:2007-08-30
  • 通讯作者: 王恒

Cloning and Optimized Prokaryotic Expression of a pbmag-1 cDNA Fragment from Plasmodium berghei ANKA

GAO Yu-hui;WANG Heng   

  1. Etiology Department, Institute of Basic Medical Sciences, CAMS and PUMC, Beijing 100005, China
  • Received:1900-01-01 Revised:1900-01-01 Online:2007-08-30 Published:2007-08-30
  • Contact: WANG Heng

摘要: 【摘要】 目的 克隆并表达伯氏疟原虫pbmag-1基因cDNA片段。 方法 在GenBank中检索伯氏疟原虫编码基因pbmag-1部分cDNA序列, 设计特异引物, 经RT-PCR从伯氏疟原虫ANKA株扩增出该基因的部分cDNA片段。 以锚定Oligo dT引物反转录mRNA获得的cDNA为模板, 利用已知序列设计特异引物, 通过cDNA末端快速扩增(RACE)技术延伸pbmag-1 3′端未知的编码序列, 并将其克隆于原核表达载体后转入大肠埃希菌(E. coli)BL21-(DE3)-RIL 株, 经优化诱导条件, 表达了重组蛋白PbMAg-1并用其免疫小鼠。 结果 获得1 341 bp具有完整3′末端序列的pbmag-1基因片段, 其A/T含量为73%。以包涵体形式表达的重组蛋白免疫小鼠, 其血清抗体经蛋白质印迹(Western blotting)分析, 能特异性地识别伯氏疟原虫感染红细胞相对分子质量约为Mr 64 000的蛋白。 结论 获得重组蛋白PbMAg-1的3′端完整的pbmag-1基因cDNA片段, 为研究伯氏疟原虫PbMAg-1蛋白在鼠疟免疫反应中的作用奠定了实验基础。

关键词: pbmag-1, 伯氏疟原虫, 基因克隆, 原核表达

Abstract: 【Abstract】 Objective To clone and express a novel gene cDNA fragment, pbmag-1, from Plasmodium berghei ANKA strain. Methods The cDNA sequence of pbmag-1 was obtained from the GenBank of P.berghei ANKA genomic databases, with which a pair of primers was designed and RT-PCR was used to get a cDNA fragment of the gene from the parasite. The expanded cDNA 3′ fragment of the gene was obtained by 3′-RACE using the oligo dT primer and a set of specific primers. The intact cDNA 3′ fragment was cloned into a prokaryotic expressional vector and transformed into the BL21-(DE3)-RIL strain of Escherichia coli. The recombinant protein of PbMAg-1 was expressed with an optimized strategy and used to immunize mice. Results The pbmag-1 cDNA fragment obtained was 1 341 bp in length, A/T rich (73%) and with a correct 3′ end sequence. By Western blot, the anti-serum of mice immunized with the recombinant protein of PbMAg-1/GST, which was expressed as inclusion bodies, specifically recognized a band with Mr 64 000 molecule from the protein extracts of P. berghei-infected mouse erythrocytes. Conclusion The pbmag-1 cDNA sequence with intact 3′ has been obtained, which will be used for further study on its role in the immune response of P. berghei infection.

Key words: pbmag-1, Plasmodium berghei, Gene cloning, Prokaryotic expression