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bioRxiv · 10.1101/2022.07.28.501842

Infection cycle and phylogeny of the Polinton-like virus Phaeocystis globosa virus virophage-14T

Roitman, S.·Rozenberg, A.·Lavy, T.·Brussaard, C. P. D.·Kleifeld, O.·Beja, O.
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Abstract

Virophages are small dsDNA viruses dependent on a nucleocytoplasmic large-DNA virus infection of a cellular host for replication. Putative virophages infecting algal hosts are classified together with polinton-like viruses, transposable elements widely found in algal genomes, yet the lack of isolated strains raises questions about their existence as independent entities. In this work we isolated and characterized a virophage (PgVV-14T) co-infecting Phaeocystis globosa with the Phaeocystis globosa virus-14T (PgV-14T). PgVV-14T decreases the fitness of its PgV-14T viral host, yet it does not salvage the cellular host population. We found viral-like elements resembling PgVV-14T in Phaeocystis genomes, suggesting that these virophages are capable of integrating to the cellular host genome, bridging the gap between Polinton-like viruses and virophages. This system, with a giant virus, a virophage and endogenous viral elements preying on an algal host, presents an opportunity to gain a better understanding on the evolution of eukaryotes and their viruses.

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Roitman, S., Rozenberg, A., Lavy, T., Brussaard, C. P. D., Kleifeld, O., Beja, O.. 2022-07-28. Infection cycle and phylogeny of the Polinton-like virus Phaeocystis globosa virus virophage-14T. https://doi.org/10.1101/2022.07.28.501842

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