猪瘟病毒Thiverval株3′非编码区插入片段对病毒拯救的影响  

Influence of insertion in the 3'untranslated region on the rescue of attenuated classical swine fever virus

作　　者：范运峰[1,2] 赵启祖[1] 赵耘[1] 邹兴启[1] 张仲秋[1,2] 王琴[1] 宁宜宝[1] 

机构地区：[1]中国兽医药品监察所,北京100081 [2]中国动物疫病预防控制中心,北京100026

出　　处：《中国预防兽医学报》2009年第6期420-423,共4页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家自然科学基金(30571377);国家863计划(2006AA10A204)

摘　　要：猪瘟病毒(CSFV)疫苗株Thiverval株与亲本病毒Alfort株相比,最明显的区别就是其3'-UTR含有一定长度的插入序列。本研究通过反向遗传学操作,构建了3'-UTR含有19nt、32nt以及插入片段完全缺失的CSFV Thiverval株全长cDNA感染性克隆,将突变病毒基因组进行体外转录,利用BHK-21细胞转染、PK-15细胞传代增殖的方式成功的从3种重组突变感染性克隆中拯救出活病毒粒子,表明CSFV疫苗株3'-UTR插入片段并不影响病毒的拯救。通过3'-UTR二级结构模拟,发现疫苗株的插入片段导致3'-UTR空间构型发生改变、自由能升高、影响二级结构的稳定性,可能是导致疫苗株毒力减弱的原因之一。The Thiverval vaccine strain of classical swine feuer virus （CSFV） differs from its parent Alfort strain by having an insertion in the 3′-UTR of genome. In this study, a series of CSFV Thiverval strain infectious cDNA clone with different insertions or complete deletion of insertion in the 3′-UTR were constructed through reverse genetics. Viruses were rescued from all the cDNA clone using the BHK-21 cells for transfection and PK-15 cells for multiplication. The results showed that insertion in 3′-UTR of attenuated CSFV did not effect the virus rescue, and it was not the decisive factor for maintaining viable virus. Secondary structure Modeling of the 3′-UTR suggests that the T-rich insertion could result in the change of structure and free energy, thus affecting the stability of the 3′-UTR structure, which could account for the attenuation of vaccine strain.

关 键 词：猪瘟病毒 3′非编码区 插入片段 病毒拯救 二级结构分析 

分 类 号：S852.651[农业科学—基础兽医学]