Extant hybrids of RNA viruses and viroid-like elements

Forgia, M.; Navarro, B.; Daghino, S.; Cervera, A.; Gisel, A.; Perotto, S.; Aghayeva, D. N.; Akinyuwa, M. F.; Gobbi, E.; Zheludev, I. N.; Edgar, R. C.; Chikhi, R. C.; Turina, M.; Babaian, A.; Di Serio, F.; de la Pena, M.

doi:10.1101/2022.08.21.504695

bioRxiv · 10.1101/2022.08.21.504695

Extant hybrids of RNA viruses and viroid-like elements

Forgia, M.·Navarro, B.·Daghino, S.·Cervera, A.·Gisel, A.·Perotto, S.·Aghayeva, D. N.·Akinyuwa, M. F.·Gobbi, E.·Zheludev, I. N.·Edgar, R. C.·Chikhi, R. C.·Turina, M.·Babaian, A.·Di Serio, F.·de la Pena, M.

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Abstract

Earths life may have originated as self-replicating RNA. Some of the simplest current RNA replicators are RNA viruses, defined by linear RNA genomes encoding an RNA-dependent RNA polymerase (RdRP), and subviral agents with single-stranded, circular RNA genomes, such as viroids encoding paired self-cleaving ribozymes. Amongst a massive expansion of candidate viroid and viroid-like elements, we report that fungal pathogens, ambiviruses, are viroid-like elements which undergo rolling circle replication and encode their own viral RdRP, thus they are a distinct hybrid infectious agent. These findings point to a deep evolutionary history between modern RNA viruses and sub-viral elements and offer new perspectives on the evolution of primordial infectious agents, and RNA life. One-Sentence SummaryNovel infectious agents resembling self-cleaving viroid-like RNAs whilst encoding a viral RNA-dependent RNA polymerase.

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Forgia, M., Navarro, B., Daghino, S., Cervera, A., Gisel, A., Perotto, S., Aghayeva, D. N., Akinyuwa, M. F., Gobbi, E., Zheludev, I. N., Edgar, R. C., Chikhi, R. C., Turina, M., Babaian, A., Di Serio, F., de la Pena, M.. 2022-08-21. Extant hybrids of RNA viruses and viroid-like elements. https://doi.org/10.1101/2022.08.21.504695

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