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Updated: Jun 27, 2026
12:30
Use of a Recombinant Mosquito Densovirus As a Gene Delivery Vector for the Functional Analysis of Genes in Mosquito Larvae
Published on: October 6, 2017
Alphavirus-derived small RNAs modulate pathogenesis in disease vector mosquitoes.
Kevin M Myles1, Michael R Wiley, Elaine M Morazzani
1Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA. mylesk@vt.edu
Summary
Mosquito-borne viruses rely on RNA interference (RNAi) for mosquito survival. Virus-derived small interfering RNAs (viRNAs) are crucial for controlling alphavirus infections in mosquitoes, ensuring viral transmission.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Mosquito-borne viruses cause significant human and animal disease.
- Viral transmission requires persistent, nonpathogenic infections in mosquito vectors.
- The RNAi pathway's role in antiviral defense in mammals remains unclear.
Purpose of the Study:
- To investigate the role of virus-derived small interfering RNAs (viRNAs) in mosquito antiviral defense.
- To determine the importance of the RNAi pathway in mosquito survival during alphavirus infection.
Main Methods:
- Identification of 21 nt viRNAs in Aedes aegypti infected with Sindbis virus (SINV).
- Analysis of viRNA distribution across the SINV genome.
- Infection of mosquitoes with recombinant alphaviruses expressing RNA silencing suppressors.
Main Results:
- Virus-derived small interfering RNAs (viRNAs) were identified in SINV-infected Aedes aegypti.
- viRNAs exhibited an asymmetric distribution spanning the viral genome.
- Suppression of viRNA accumulation led to decreased mosquito survival.
Conclusions:
- An exogenous siRNA pathway is essential for mosquito survival following alphavirus infection.
- viRNAs play a critical role in controlling alphavirus replication and pathogenesis in mosquitoes.
- This antiviral RNAi mechanism is vital for the natural maintenance of mosquito-borne alphaviruses.
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