Send to

Choose Destination
J Virol. 2018 Dec 19. pii: JVI.02068-18. doi: 10.1128/JVI.02068-18. [Epub ahead of print]

M segment-based minigenomes and virus-like particle assays as an approach to assess the potential of tick-borne Phlebovirus genome reassortment.

Author information

MRC-University of Glasgow Centre for Virus Research, Glasgow, Scotland, United Kingdom.
MRC-University of Glasgow Centre for Virus Research, Glasgow, Scotland, United Kingdom


Bunyaviruses have a tripartite negative-sense RNA genome. Due to the segmented nature of these viruses, if two closely related viruses co-infect the same host or vector cell, it is possible that RNA segments from either of the two parental viruses are incorporated into progeny virions to give reassortant viruses. Little is known about the ability of tick-borne phleboviruses to reassort. The present study describes the development of minigenome assays for the tick-borne viruses Uukuniemi phlebovirus (UUKV) and Heartland phlebovirus (HRTV). We used these minigenome assays in conjunction with the existing minigenome system of SFTS phlebovirus (SFTSV) to assess the ability of viral N and L proteins to recognize, transcribe and replicate the M segment-based minigenome of a heterologous virus. The highest minigenome activity was detected with the M segment-based minigenome of cognate viruses. However, our findings indicate that several combinations utilizing N and L proteins of heterologous viruses resulted in M segment minigenome activity. This suggests that the M segment untranslated regions (UTRs) are recognised as a functional promoter of transcription and replication by the N and L proteins of related viruses. Further, virus-like particle assays demonstrated that HRTV glycoproteins can package UUKV and SFTSV S and L segment-based minigenomes. Taken together, these results suggest that co-infection of these viruses could lead to the generation of viable reassortant progeny. Thus, the tools developed herein could aid in understanding the role of genome reassortment in the evolution of these emerging pathogens under an experimental setting.IMPORTANCE In recent years, there has been a large expansion in the number of tick-borne viruses emerging that are assigned to the Phlebovirus genus. Bunyaviruses have a tripartite segmented genome and infection of the same host cell by two closely related bunyaviruses can in theory result in eight potential progeny viruses, with different genome segment combinations. We used genome analogues expressing reporter genes to assess the ability of phlebovirus nucleocapsid protein and RNA-dependent RNA polymerase to recognize the untranslated region of a genome segment of related phleboviruses, and virus-like particle assays to assess whether viral glycoproteins can package genome analogues of related phleboviruses. Our results provide strong evidence that these emerging pathogens could reassort their genomes if they were to meet in nature in an infected host or vector. This reassortment process can result in viruses with new pathogenic properties.

Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center