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bioRxiv · 10.64898/2026.03.30.715342

Infection with non-retroviral RNA viruses produces virus-derived DNA across diverse insect species

Bilsen, A.·Ottati, S.·Parise, C.·Abba, S.·Vanden Broeck, J.·Galetto, L.·Santos, D.
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Abstract

Growing evidence shows that eukaryotic genomes contain DNA sequences of non-retroviral RNA virus origin, yet the mechanisms underlying the generation of this virus-derived complementary DNA (vDNA) remain poorly understood, particularly in insects. Here, we demonstrate that infection with diverse non-retroviral RNA viruses induces the production of reverse-transcribed vDNA across multiple lepidopteran and hemipteran species. We further show that a Drosophila melanogaster-derived cell line actively secretes reverse-transcribed vDNA associated with extracellular vesicles (EVs), widely conserved nanoscale mediators of intercellular communication. Together, these findings reveal that infection-induced vDNA formation is a widespread phenomenon in insects and suggest that EVs may facilitate the systemic dissemination of vDNA.

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Bilsen, A., Ottati, S., Parise, C., Abba, S., Vanden Broeck, J., Galetto, L., Santos, D.. 2026-03-31. Infection with non-retroviral RNA viruses produces virus-derived DNA across diverse insect species. https://doi.org/10.64898/2026.03.30.715342

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