摘要
目的 :比较我国 195 3年从患者脑组织分离的森张株和 2 0 0 1年从患者血清中分离的MDJ0 1株森林脑炎病毒 (TBE)的生物学特性及E蛋白基因核苷酸序列的变化 ,分析TBE病毒E蛋白基因的变化与功能的关系 ,从分子水平上探讨我国TBE的传播、流行规律及致病机制。方法 :两株病毒同时接种乳鼠和BHK 2 1细胞 ,观察两株病毒对乳鼠和BHK 2 1细胞的致病性 ;从两株病毒感染的BHK 2 1细胞中提取病毒的RNA ,对E蛋白基因进行RT_PCR扩增 ,扩增产物纯化后与pGEM_T载体连接 ,分别进行克隆测序。结果 :森张株对乳鼠和BHK 2 1的致病性均比MDJ0 1株明显 ;两株病毒E蛋白基因长为 14 88nt,编码 4 96个氨基酸 ,核苷酸的变异为 33个 ,导致了 2个氨基酸的变化 ,第一个氨基酸的变异发生在 113位 (MDJ0 1株由I变成V) ,第二个氨基酸的变异发生在 16 3位 (MDJ0 1由P变成A) ,两株病毒核苷酸序列的同源性为 97.8% ,推测的氨基酸序列的同源性为 99.6 %。与国外远东株比较 ,森张株核苷酸序列的同源性稍高于MDJ0 1株 ,与欧洲株、西伯利亚株的同源性基本一致。结论 :新分离株MDJ0 1对细胞和乳鼠的致病性稍低于 195 3年分离的森张株 ,E蛋白基因的核苷酸序列分析表明两株病毒同属于远东亚型 ,推测MDJ0 1株可能是由森张株在自然界长期演变而来。
Objective:To compare the biological function and variation of E protein gene nucleotide of two strains of tick_borne encephalitis(TBE) viruses isolated in 1953 ( Senzhang strain) and 2001 (MDJ01 strain) in China.Methods:The suspensions of mouse brains infected by Senzhang and MDJ01 strains were inoculated into suckling mice and BHK/21 cells. Total RNA was extracted from BHK/21 cells infected by Senzhang and MDJ01 strains. The E protein gene was amplified by RT_PCR and the amplified fragment was cloned in pGEM_T easy vector. The nucleotide sequence was determined by PRISM TM ABI377automated sequencer.Results:Two virus strains were different in virulence to suckling mice and BHK/21 cells. The E gene of both strains was 1?488 nucleotides in length. nucleotide sequence homology was 97.2% and deduced amino acid sequence homology was 99.6%. Comparison of nucleotide sequences of Senzhang and MDJ01 strains with far_eastern subtype respectively found that homology of Senzhang strain was higher than that of MDJ01 strain. Homology of the two strains was similar in comparison with Europe and Siberia subtypes.Conclusion:The virulence of the two virus strains in suckling mice and BHK/21 cells was different with MDJ01 strain being weaker than Senzhang strain. Nucleotide sequence analysis of the E gene of two virus strains showed that they belonged to Far_eastern subtype of tick_borne encephalitis virus. MDJ01 strain may be a variant of Senzhang strain. [
出处
《军事医学科学院院刊》
CSCD
北大核心
2003年第4期259-261,285,共4页
Bulletin of the Academy of Military Medical Sciences
基金
军事医学科学院创新基金 ( 0 2 0 80 49)
