Narnavirus
Narnavirus | |
---|---|
Narnaviruses have no capsid or viral envelope, RNA genome and RdRp form a naked ribonucleoprotein complex | |
Virus classification | |
(unranked): | Virus |
Realm: | Riboviria |
Kingdom: | Orthornavirae |
Phylum: | Lenarviricota |
Class: | Amabiliviricetes |
Order: | Wolframvirales |
Family: | Narnaviridae |
Genus: | Narnavirus |
Species | |
Narnavirus is a genus of positive-strand RNA viruses in the family Narnaviridae. Fungi serve as natural hosts. There are two species in this genus.[1][2] Member viruses have been shown to be required for sexual reproduction of Rhizopus microsporus ("Narnaviruses decrease asexual reproduction, but together with Mycetohabitans, are required for sexual reproductive success. This fungal–bacterial-viral system represents an outstanding model to investigate three-way microbial symbioses and their evolution.").[3] Narnaviruses have a naked RNA genome without a virion and derive their name from this feature.[4]
Virology
[edit]Structure
[edit]Narnaviruses have no true virion. They do not have structural proteins or a capsid.[5]
Genome
[edit]Narnaviruses have nonsegmented, linear, positive-sense, single-stranded RNA genomes. The genome has one open reading frame which encodes the RNA-dependent RNA polymerase (RdRp). The genome is associated with the RdRp in the cytoplasm of the fungi host and forms a naked ribonucleoprotein complex.[2]
Replication cycle
[edit]Viral replication is cytoplasmic. Replication follows the positive-strand RNA virus replication model. Positive-strand RNA virus transcription is the method of transcription. The virus exits the host cell by cell-to-cell movement. Fungi serve as the natural host. Transmission routes are parental and sexual.[2]
Taxonomy
[edit]The genus has the following two species:[1]
References
[edit]- ^ a b "Virus Taxonomy: 2020 Release". International Committee on Taxonomy of Viruses (ICTV). March 2021. Retrieved 16 May 2021.
- ^ a b c "Viral Zone". ExPASy. Retrieved 15 June 2015.
- ^ Espino-Vázquez AN; Bermúdez-Barrientos JR; Cabrera-Rangel JF; Córdova-López G; Cardoso-Martínez F; Martínez-Vázquez A; Camarena-Pozos DA; Mondo SJ; Pawlowska TE; Abreu-Goodger C; Partida-Martínez LP. (2020). "Narnaviruses: Novel players in fungal–bacterial symbioses". The ISME Journal. 14 (7): 1743–1754. doi:10.1038/s41396-020-0638-y. PMC 7305303. PMID 32269378.
- ^ "Narnaviridae - Positive Sense RNA Viruses - Positive Sense RNA Viruses (2011) - ICTV". talk.ictvonline.org. Retrieved 15 June 2021.[dead link ]
- ^ Dolja, V. V.; Koonin, E. V. (2012). "Capsid-Less RNA Viruses". ELS. doi:10.1002/9780470015902.a0023269. ISBN 978-0-470-01617-6.