Ambiviricota, a novel ribovirian phylum for viruses with viroid-like properties.
J Virol
; 98(7): e0083124, 2024 Jul 23.
Article
in En
| MEDLINE
| ID: mdl-38856119
ABSTRACT
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.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Viroids
/
Open Reading Frames
/
Genome, Viral
Language:
En
Journal:
J Virol
Year:
2024
Type:
Article
Affiliation country:
United States