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.[3] Narnaviruses have a naked RNA genome without a virion and derive their name from this feature.[4]
| Narnavirus | |
|---|---|
 | |
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| 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 | |
Virology
Structure
Narnaviruses have no true virion. They do not have structural proteins or a capsid.[5]
Genome
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
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
The genus has the following two species:[1]
- Saccharomyces 20S RNA narnavirus
- Saccharomyces 23S RNA narnavirus