Induction of type I IFN response by alphavirus replicases in the absence of viral RNA templates
Date
2023
Authors
Journal Title
Journal ISSN
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Publisher
Tartu Ülikool
Abstract
Alphaviruses are arthropod transmitted viruses with global distribution and wide host range.
Upon infection, some alphaviruses may cause acute muscle pain, arthritis, rash, and
encephalitis. In the past decades alphavirus-caused epidemics are not uncommon, but despite
that there are currently no licensed vaccines or antiviral drugs for any of the alphavirus species.
During viral replication and transcription, alphavirus replicase generates 5’-triphosphate RNA
and double-stranded RNA (dsRNA), which trigger type I interferon production. Remarkably, it
has been shown that SFV and SINV replicases induce IFN- response in absence of viral RNA
templates by generating 5’-ppp dsRNA from host cell RNA. In the current work we investigated
whether some other alphavirus replicases possess such property and how it differs in human
and insect cells. We observed that other alphavirus replicases can generate IFN-inducing RNA
without presence of viral RNA templates. We also concluded that correlation between
replicase’s ability to transcribe and replicate viral RNA template and its ability to synthesize
IFN-inducing RNA from host’s cellular RNA is not universal attribute of all alphaviruses.
Description
Keywords
alphavirus, alphavirus replicase, RNA pathogen-associated molecular patterns, type I interferons