Anellovirus protein coded by ORF2/3 recruits host cell replication andhomologous recombination machinery during replication

Boisvert, N.; Thurmond, S.; Elenberger, C.; Jeraldo, P.; Prince, C.; Sutherland, N.; Melo, J.; Tsheowang, K.; Dodier, C.; Nogalski, M.; Verma, D.; Parsons, G. B.; Cabral, J.

doi:10.1101/2025.05.28.656439

bioRxiv · 10.1101/2025.05.28.656439

Anellovirus protein coded by ORF2/3 recruits host cell replication andhomologous recombination machinery during replication

Boisvert, N.·Thurmond, S.·Elenberger, C.·Jeraldo, P.·Prince, C.·Sutherland, N.·Melo, J.·Tsheowang, K.·Dodier, C.·Nogalski, M.·Verma, D.·Parsons, G. B.·Cabral, J.

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Abstract

Anelloviridae is a family of single-stranded DNA viruses that are thought to be non-pathogenic and commensal. Despite their ubiquitous presence in human populations, little is known about the anellovirus mechanism of replication in host cells. We identified the protein coded by ORF2/3 as necessary and sufficient to initiate replication from the minimal origin of replication for viruses of both the Beta- and Alphatorquevirus genera. Supporting this observation, we identified components of the polymerase alpha and BTR complexes as interacting with the viral replication initiation protein (Rip) during DNA replication, suggesting a recombination-dependent mechanism of replication that uses host cell machinery to mediate dissolution of replication intermediates. Furthermore, we mapped a 92-bp minimal origin of replication sequence for the Betatorquevirus genus comprised of an AT-rich stretch and a portion of the GC-rich region. Altogether, this study provides a first insight into the mechanism by which anelloviruses manipulate host cell machinery to facilitate viral genome replication and represents a significant step forward in understanding the complex processes underlying anellovirus replication and persistent infection of these important commensal viruses.

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Boisvert, N., Thurmond, S., Elenberger, C., Jeraldo, P., Prince, C., Sutherland, N., Melo, J., Tsheowang, K., Dodier, C., Nogalski, M., Verma, D., Parsons, G. B., Cabral, J.. 2025-05-30. Anellovirus protein coded by ORF2/3 recruits host cell replication andhomologous recombination machinery during replication. https://doi.org/10.1101/2025.05.28.656439

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