Mapping of transcription termination within the S segment of SFTS phlebovirus facilitated the generation of NSs-deletant viruses

Brennan, B. , Rezelj, V. V. and Elliott, R. M. (2017) Mapping of transcription termination within the S segment of SFTS phlebovirus facilitated the generation of NSs-deletant viruses. Journal of Virology, 91(16), e00743-17. (doi:10.1128/JVI.00743-17) (PMID:28592543) (PMCID:PMC5533932)

[img]
Preview
Text
142357.pdf - Published Version
Available under License Creative Commons Attribution.

2MB

Abstract

SFTS phlebovirus (severe fever with thrombocytopenia syndrome virus; SFTSV) is an emerging tick-borne bunyavirus that was first reported in China in 2009. Here we report the generation of a recombinant SFTSV (rHB29NSsKO) that cannot express the viral non-structural protein (NSs) upon infection of cells in culture. We show that rHB29NSsKO replication kinetics are greater in interferon (IFN)-incompetent cells and that the virus is unable to suppress IFN induced in response to viral replication. The data confirm for the first time in the context of virus infection that NSs acts as a virally encoded IFN antagonist and that NSs is dispensable for virus replication. Using 3’ RACE we mapped the 3’ -end of the N and NSs mRNAs, showing that the mRNAs terminate within the coding region of the opposite open reading frame. We show that the 3’ end of the N mRNA terminates upstream of a 5’ -GCCAGCC-3’ motif present in the viral genomic RNA. With this knowledge, and using virus-like particles, we could demonstrate that the last 36 nt of the NSs ORF were needed to ensure the efficient termination of the N mRNA and were required for recombinant virus rescue. We demonstrate it is possible to recover viruses lacking NSs, expressing just a 12 amino acid NSs peptide or viruses encoding eGFP or a NSs-eGFP fusion protein in the NSs locus. This opens the possibility for further studies of NSs and potentially the design of attenuated viruses for vaccination studies.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Brennan, Dr Benjamin and Elliott, Professor Richard and Rezelj, Veronica Valentina
Authors: Brennan, B., Rezelj, V. V., and Elliott, R. M.
College/School:College of Medical Veterinary and Life Sciences > Institute of Infection Immunity and Inflammation
Journal Name:Journal of Virology
Publisher:American Society for Microbiology
ISSN:0022-538X
ISSN (Online):1098-5514
Published Online:07 June 2017
Copyright Holders:Copyright © 2017 The Authors
First Published:First published in Journal of Virology 91(16):e00743-17
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
635361Molecular analyses of arbovirus-host interactionsMassimo PalmariniWellcome Trust (WELLCOTR)099220/B/12/ZMVLS III - CENTRE FOR VIRUS RESEARCH