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bioRxiv · 10.1101/2024.08.02.606351

A new clade of pararetroviruses distantly related to hepadnaviruses and nackednaviruses

Buigues, J.·Vinals, A.·Martinez-Recio, R.·Monros, J. S.·Cuevas, J. M.·Sanjuan, R.
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Abstract

Group VII of the Baltimore classification comprises reverse-transcribing, non-integrated DNA viruses, also known as pararetroviruses. These include the hepadnaviruses, a family of small enveloped DNA viruses that infect vertebrates, but also a sister family of non-enveloped fish viruses, the nackednaviruses. Here we describe the complete sequence of a new pararetrovirus found in the feces of an insectivorous bat. This virus encodes a core protein and a reverse transcriptase but no envelope protein. A database search identified a viral sequence from a permafrost sample as its closest relative. The two viruses form a cluster that occupies a basal phylogenetic position relative to hepadnaviruses and nackednaviruses, with an estimated divergence time of 500 million years. These findings may lead to the definition of a new viral family and support the hypothesis that ancestral animal pararetroviruses were non-enveloped.

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Buigues, J., Vinals, A., Martinez-Recio, R., Monros, J. S., Cuevas, J. M., Sanjuan, R.. 2024-08-04. A new clade of pararetroviruses distantly related to hepadnaviruses and nackednaviruses. https://doi.org/10.1101/2024.08.02.606351

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