Recurrent evolution of high virulence in isolated populations of a DNA virus
Abstract
Hosts and viruses are constantly evolving in response to each other: as a host attempts to suppress a virus, the virus attempts to evade and suppress the host's immune system. Here we describe the recurrent evolution of a virulent strain of a DNA virus which infects multiple Drosophila species. Specifically, we identified two distinct viral types that differ 100-fold in viral titer in infected individuals, with similar differences observed in multiple species. Our analysis suggests that one of the viral types appears to have recurrently evolved at least 4 times in the past ~30,000 years, 3X in Arizona and once in another geographically distinct species. This recurrent evolution may be facilitated by an effective mutation rate which increases as each prior mutation increases viral titer and effective population size. The higher titer viral type suppresses the host immune system and an increased virulence compared to the low viral titer type.
Data availability
Sequencing data have been deposited on the NCBI SRA under the study accession: SRP187240Genomes used in this study are available at the following accessions:Drosophila innubila - GCF_004354385.1Drosophila innubila Nudivirus - GCF_004132165.1Drosophila azteca - GCA_005876895.1
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Drosophila Sky Island data analysisDryad Digital Repository, doi:10.5061/dryad.2fqz612mh.
Article and author information
Author details
Funding
KU CMADP (P20 GM103638)
- Tom Hill
- Robert L Unckless
K-INBRE (P20 GM103418)
- Tom Hill
National Institutes of Health (R00 GM114714)
- Robert L Unckless
National Institutes of Health (R01 AI139154)
- Robert L Unckless
National Science Foundation (DEB-1737824)
- Tom Hill
- Robert L Unckless
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Dieter Ebert, University of Basel, Switzerland
Version history
- Received: May 14, 2020
- Accepted: October 28, 2020
- Accepted Manuscript published: October 28, 2020 (version 1)
- Version of Record published: November 24, 2020 (version 2)
Copyright
© 2020, Hill & Unckless
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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- Developmental Biology
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