传染性法氏囊病病毒基因组A节段3'-UTR对病毒复制影响的研究

摘要

为探究传染性法氏囊病病毒(IBDV)基因组A节段3’-UTR是否影响IBDV的复制,本实验应用融合PCR技术将IBDV弱毒Gt株A节段的3’-UTR替换为超强毒Gx株的相应区段,并利用反向遗传操作系统拯救嵌合病毒rGt-Gx3'UTR,对拯救病毒进行鉴定.结果显示嵌合病毒拯救成功,Gt株的RNA依赖的RNA聚合酶既能识别Gt株的3’-UTR,也能识别超强毒Gx株的3’-UTR.通过比较嵌合病毒与亲本病毒的体外复制曲线,表明3’-UTR能够影响IBDV的复制.3’-UTR二级结构的预测结果表明其可能是以特定的二级结构而非一级序列发挥其功能.本研究为认识IBDV复制特点奠定了基础.%In order to explore whether the 3'-un-translated region (3'-UTR) of segment A influences the replication of infectious bursal disease virus (IBDV),the fusion PCR technology was used to replace 3'-UTR of attenuated Gt strain with the corresponding section of very virulent IBDV (vvIBDV) Gx strain and rescued another chimeric virus named rGt-Gx3'UTR successfully.The results of viral replication kinetic curves showed that 3'-UTR of segment A could affect the replication of IBDV.Moreover,the RNA dependent RNA polymerase of Gt not only could identify the Gt-3'UTR but also could identify vvIBDV Gx-3'UTR.Besides,we predicted the 3'-UTR secondary structure and made the speculation that 3'-UTR with specific secondary structure rather than the primary sequence played its function.This study offers the foundation for further research on replication of IBDV.