Entomophthovirus: an insect-derived iflavirus that infects a behavior-manipulating fungal pathogen of dipterans
Maxwell C Coyle1, Carolyn N Elya1, Michael J Bronski1
1Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, USA.
Abstract:
We report a virus infecting Entomophthora muscae, a behavior-manipulating fungal pathogen of dipterans. The virus, which we name Berkeley Entomophthovirus, is a positive-strand RNA virus in the iflaviridae family of capsid-forming viruses, which are mostly known to infect insects. The viral RNA is expressed at high levels in fungal cells in vitro and during in vivo infections of Drosophila melanogaster, and virus particles can be seen intracellularly in E. muscae. This virus, of which we find two closely related variants in our culture of E. muscae, is also closely related to three different viruses reported from metagenomic surveys, two of which were isolated from wild dipterans, and a third isolated from wild ticks. By analyzing sequencing data from these earlier reports, we find abundant reads aligning to E. muscae specifically in the samples from which viral reads were sequenced. These data establish a wide and perhaps obligate association with E. muscae in the wild, consistent with our laboratory data that E. muscae is the host for these closely related viruses. Because of this, we propose the name Entomophthovirus (EV) for this group of highly related virus variants. As other members of the iflaviridae have been reported to cause behavioral changes in insects, we speculate on the possibility that EV plays a role in the behavioral manipulation of flies infected with E. muscae.
Insights
A novel virus, Berkeley Entomophthovirus, infects the behavior-manipulating fungus Entomophthora muscae. This discovery suggests a potential role for this virus in altering host fly behavior.
Area of Science:
- Virology
- Mycology
- Entomology
Background:
- Entomophthora muscae is a fungal pathogen known to manipulate insect behavior.
- The iflaviridae family comprises viruses primarily known to infect insects.
Purpose of the Study:
- To identify and characterize a novel virus infecting Entomophthora muscae.
- To investigate the relationship of this virus to other known viruses.
- To explore the potential role of the virus in host behavior manipulation.
Main Methods:
- Virus isolation and characterization from Entomophthora muscae.
- In vitro and in vivo expression analysis of viral RNA in fungal and insect hosts (Drosophila melanogaster).
- Phylogenetic analysis of viral sequences and comparison with metagenomic data.
Main Results:
- A new positive-strand RNA virus, named Berkeley Entomophthovirus (EV), was identified within E. muscae.
- Viral RNA expression was high in fungal cells, and virus particles were observed intracellularly.
- EV showed close relatedness to viruses found in metagenomic surveys of dipterans and ticks, indicating a broader association with E. muscae.
Conclusions:
- Berkeley Entomophthovirus (EV) is closely associated with Entomophthora muscae, likely representing a new group within the iflaviridae family.
- The findings suggest a potentially obligate association between EV and E. muscae in the wild.
- Further research is warranted to determine if EV contributes to the behavioral manipulation observed in fly hosts infected by E. muscae.
