日本血吸虫SjBT基因的获得与生物信息学分析

目的　从日本血吸虫 (Schistosomajaponicum ,Sj)成虫cDNA文库中获得并分析日本血吸虫新基因 ,为防治日本血吸虫病提供药物靶标或候选疫苗。　方法　构建日本血吸虫成虫cDNA文库 ,用序列标签法随机挑取重组阳性克隆进行测序 ,对部分序列进行步移法测序获取其全长cDNA ,并进行生物信息学分析和登录。　结果　获得了 1个日本血吸虫新基因 ,全长 14 3 9bp ,编码 44 3个氨基酸 ,与肝片形吸虫微管蛋白基因具有 79%的同源性。编码蛋白的理论分子质量为 7.2 198ku ,等电点为 9.12 ;抗原表位可能位于cDNA序列 3 73～ 3 96处。　结论　表达序列标签法、步移法测序和生物信息学技术有利于发现日本血吸虫新基因。

ACQUIRING AND BIOINFORMATICS ANALYZING OF BETA-TUBULIN GENE OF SCHISTOSOMA JAPONICUM

Objective To acquire and analyze new genes from an adult Schistosoma japonicum cDNA library and so as to search new drug targets or vaccine candidates for preventing,controlling and treating schistosomasis. Methods A cDNA library was constructed from S. japonicum (Chinese strain) adult stage. Clones were selected randomly from the cDNA library and were sequenced by using the method of expression sequence Tags (ESTs). Novel genes,including beta-tubulin gene were acquired by primer-walking form some ESTs and after analyzing with bioinformatics methods in GenBank database and in Expasy database. Results Beta-tubulin genes,1 439 bp and coding for 443 amino acids,was acquired and submitted to GenBank to get an accession number that was AY220457. The beta-tubulin gene of S. japonicum and Fasciola hepatica were homologous with identity 79%. The academic pI was 9.12,and the antigen determinant was probably from 373 to 396 on the cDNA sequence. Conclusion It is a feasible method to discover and acquire novel genes of S. japonicum by ESTs,combination of primer-walking sequncing and bioinformatics technique.