Fungi harbor a vast diversity of mobile genetic elements (MGEs). Recently, novel fungal MGEs, tentatively referred to as 'ambiviruses,' were described. 'Ambiviruses' have single-stranded RNA genomes of about 4-5 kb in length that contain at least two open reading frames (ORFs) in non-overlapping ambisense orientation. Both ORFs are conserved among all currently known 'ambiviruses,' and one of them encodes a distinct viral RNA-directed RNA polymerase (RdRP), the hallmark gene of ribovirian kingdom Orthornavirae. However, 'ambivirus' genomes are circular and predicted to replicate via a rolling-circle mechanism. Their genomes are also predicted to form rod-like structures and contain ribozymes in various combinations in both sense and antisense orientations-features reminiscent of viroids, virusoids, ribozyvirian kolmiovirids, and yet-unclassified MGEs (such as 'epsilonviruses,' 'zetaviruses,' and some 'obelisks'). As a first step toward the formal classification of 'ambiviruses,' the International Committee on Taxonomy of Viruses (ICTV) recently approved the establishment of a novel ribovirian phylum, Ambiviricota, to accommodate an initial set of 20 members with well-annotated genome sequences.
- Klíčová slova
- Ambiviricota, Ascomycota, Basidiomycota, ICTV, International Committee on Taxonomy of Viruses, Riboviria, ambiviricot, ambivirus, deltavirus, fungi, fungus, hairpin, hammerhead, phylum, ribozyme, twister, viroid, virus classification, virus nomenclature, virus taxonomy,
- MeSH
- fylogeneze MeSH
- genom virový * MeSH
- houby genetika virologie MeSH
- mykoviry genetika klasifikace izolace a purifikace MeSH
- otevřené čtecí rámce * MeSH
- RNA virová genetika MeSH
- RNA-dependentní RNA-polymerasa genetika MeSH
- RNA-viry genetika klasifikace MeSH
- viroidy * genetika klasifikace MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- RNA virová MeSH
- RNA-dependentní RNA-polymerasa MeSH
