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The Characterization of a Novel Virus Discovered in the Yeast Pichia membranifaciens.

ABSTRACT: Mycoviruses are widely distributed across fungi, including the yeasts of the Saccharomycotina subphylum. This manuscript reports the first double-stranded RNA (dsRNA) virus isolated from Pichia membranifaciens. This novel virus has been named Pichia membranifaciens virus L-A (PmV-L-A) and is a member of the Totiviridae. PmV-L-A is 4579 bp in length, with RNA secondary structures similar to the packaging, replication, and frameshift signals of totiviruses that infect Saccharomycotina yeasts. PmV-L-A was found to be part of a monophyletic group within the I-A totiviruses, implying a shared ancestry between mycoviruses isolated from the Pichiaceae and Saccharomycetaceae yeasts. Energy-minimized AlphaFold2 molecular models of the PmV-L-A Gag protein revealed structural conservation with the Gag protein of Saccharomyces cerevisiae virus L-A (ScV-L-A). The predicted tertiary structure of the PmV-L-A Pol and other homologs provided a possible mechanism for totivirus RNA replication due to structural similarities with the RNA-dependent RNA polymerases of mammalian dsRNA viruses. Insights into the structure, function, and evolution of totiviruses gained from yeasts are essential because of their emerging role in animal disease and their parallels with mammalian viruses.

SUBMITTER: Lee MD

PROVIDER: S-EPMC8951182 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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The Characterization of a Novel Virus Discovered in the Yeast Pichia membranifaciens.

Lee Mark D MD Creagh Jack W JW Fredericks Lance R LR Crabtree Angela M AM Patel Jagdish Suresh JS Rowley Paul A PA

Viruses 20220313 3

Mycoviruses are widely distributed across fungi, including the yeasts of the Saccharomycotina subphylum. This manuscript reports the first double-stranded RNA (dsRNA) virus isolated from Pichia membranifaciens. This novel virus has been named Pichia membranifaciens virus L-A (PmV-L-A) and is a member of the Totiviridae. PmV-L-A is 4579 bp in length, with RNA secondary structures similar to the packaging, replication, and frameshift signals of totiviruses that infect Saccharomycotin ...[more]

PMID: 35337001

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The Characterization of a Novel Virus Discovered in the Yeast Pichia membranifaciens.

Publications

The Characterization of a Novel Virus Discovered in the Yeast <i>Pichia membranifaciens</i>.

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