Establishment of a Reverse Genetic System of Severe Fever with Thrombocytopenia Syndrome Virus Based on a C4 Strain  

作　　者：Mingyue Xu Bo Wang Fei Deng Hualin Wang Manli Wang Zhihong Hu Jia Liu 

机构地区：[1]State Key Laboratory of Virology and National Virus Resource Center,Wuhan Institute of Virology,Center for Biosafety Mega-Science,Chinese Academy of Sciences,Wuhan 430071,China [2]University of the Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Virologica Sinica》2021年第5期958-967,共10页中国病毒学（英文版）

基　　金：supported by grants from the National Natural Science Foundation of China(No.31900146;Open Research Fund Program of the State Key Laboratory of Virology of China(No.2020IOV003);Team project of Health Commission of Hubei Province(WJ2019C003)。

摘　　要：Severe fever with thrombocytopenia syndrome virus(SFTSV)is an emerging tick-borne bunyavirus that causes hemorrhagic fever-like disease(SFTS)in humans with a case fatality rate up to 30%.To date,the molecular biology involved in SFTSV infection remains obscure.There are seven major genotypes of SFTSV(C1-C4 and J1-J3)and previously a reverse genetic system was established on a C3 strain of SFTSV.Here,we reported successfully establishment of a reverse genetics system based on a SFTSV C4 strain.First,we obtained the 5’-and 3’-terminal untranslated region(UTR)sequences of the Large(L),Medium(M)and Small(S)segments of a laboratory-adapted SFTSV C4 strain through rapid amplification of cDNA ends analysis,and developed functional T7 polymerase-based L-,M-and S-segment minigenome assays.Then,fulllength cDNA clones were constructed and infectious SFTSV were recovered from co-transfected cells.Viral infectivity,growth kinetics,and viral protein expression profile of the rescued virus were compared with the laboratory-adapted virus.Focus formation assay showed that the size and morphology of the foci formed by the rescued SFTSV were indistinguishable with the laboratory-adapted virus.However,one-step growth curve and nucleoprotein expression analyses revealed the rescued virus replicated less efficiently than the laboratory-adapted virus.Sequence analysis indicated that the difference may be due to the mutations in the laboratory-adapted strain which are more prone to cell culture.The results help us to understand the molecular biology of SFTSV,and provide a useful tool for developing vaccines and antivirals against SFTS.

关 键 词：BUNYAVIRUS Severe fever with thrombocytopenia syndrome virus(SFTSV) MINIGENOME Reverse genetic system T7 polymerase C4 strain 

分 类 号：R373.3[医药卫生—病原生物学]