论文部分内容阅读
目的 克隆并分析日本血吸虫(Sj)新的抗原基因,为血吸虫病疫苗研制提供有效的候选抗原分子。方法 用日本吸虫肝门型童虫表膜抗原(SjHmAg)免疫兔血清筛选日本血吸虫成虫cDNA文库,并对阳性克隆的插入片段进行PCR扩增及测序,通过互联网对测序获得的核苷酸序列进行同源性比较分析,并预测蛋白质结构与功能。结果 经3轮筛选,获10个阳性克隆,其插入的Sj成虫cDNA片段大小自0.6～3.0kb不等。对其中3个阳性克隆测序的结果显示,两个为新基因片段,SjHm1、SjHm2的Genbank登录号分别为AY118085,AY124772,分别编码79、66个氨基酸。SjHml蛋白为跨膜蛋白,含1个跨膜区,1个N-肉豆蔻酰化位点。SjHm2蛋白为一个非跨膜蛋白,含1个酪蛋白激酶Ⅱ磷酸化位点。 结论 获得的阳性克隆插入基因片段可能为编码具有保护性作用的日本血吸虫抗原的基因片段。
Objective To clone and analyze the new antigen gene of Schistosoma japonicum (Sj) and provide an effective candidate antigen for the development of schistosomiasis vaccine. Methods Rabbit Schistosoma japonicum cDNA library was screened by immunization with rabbit schistosoma japonicum schistosomula surface antigen (SjHmAg), and the inserted fragment of positive clones was amplified by PCR and sequenced. The nucleotide sequence obtained from sequencing was obtained through Internet Homology comparative analysis, and predict protein structure and function. Results After 3 rounds of screening, 10 positive clones were obtained, and the inserted cDNA fragments of Sj adults ranged from 0.6 to 3.0 kb in size. Three of the positive clones were sequenced. The two new gene fragments were SjHm1 and SjHm2 with the GenBank accession numbers AY118085 and AY124772, encoding 79 and 66 amino acids, respectively. The SjHml protein is a transmembrane protein containing 1 transmembrane region and 1 N-myristoylation site. The SjHm2 protein is a non-transmembrane protein containing one casein kinase II phosphorylation site. Conclusion The positive cloned gene fragment obtained may be a gene fragment encoding a protective Schistosoma japonicum antigen.