Endornaviridae

Endornaviridae
Endornaviridae particle. Shown is the replicative form (dsRNA) of the (+)ssRNA virus.
Virus classification
(unranked): Virus
Realm: Riboviria
Kingdom: Orthornavirae
Phylum: Kitrinoviricota
Class: Alsuviricetes
Order: Martellivirales
Family: Endornaviridae
Genera

Alphaendornavirus
Betaendornavirus

Endornaviridae is a family of viruses. Plants, fungi, and oomycetes serve as natural hosts. There are 31 species in this family, assigned to 2 genera (Alphaendornavirus and Betaendornavirus). Members of Alphaendornavirus infect plants, fungi and the oomycete Phytophthora sp., members of Betaendornavirus infect ascomycete fungi.[1][2][3][4]

Taxonomy

The following genera are assigned to the family:[1]

  • Alphaendornavirus
  • Betaendornavirus

Structure

Linear, single-stranded, positive-sense RNA genome of about 14 kb to 17.6 kb. A site specific break (nick) is found in the coding strand about 1 to 2 kb from the 5’ terminus. ViralZone conflicts with ICTV, listing Endornaviridae as dsRNA viruses.[1][2]

As the Endornaviridae genomes don't include a coat protein (CP) gene, no true virions are associated with members of this family. For Vicia faba endornavirus, the RNA genome has been associated with some pleomorphic cytoplasmic membrane vesicles.[1]

Life cycle

Viral replication is cytoplasmic. The viral replicative form of the Endornaviridae is dsRNA. Replication follows the double-stranded RNA virus replication model. Double-stranded RNA virus transcription is the method of transcription.[2][1]

As the replicative dsRNA form is relatively stable, it can be found in comparatively high quantities in host tissues, and therefore is a likely subject of isolations[1] (this is the reason why Endornaviridae often are classified as dsRNA viruses,[2] in contrast to the official ssRNA(+) ICTV classification).

The virus exits the host cell by cell to cell movement.[1][2]

Plants, fungi, and oomycetes serve as the natural hosts. Transmission routes are pollen associated.[1][2]

References

  1. ^ a b c d e f g h Valverde, RA; Khalifa, ME; Okada, R; Fukuhara, T; Sabanadzovic, S; ICTV Report, Consortium (August 2019). "ICTV Virus Taxonomy Profile: Endornaviridae". The Journal of General Virology. 100 (8): 1204–1205. doi:10.1099/jgv.0.001277. PMC 12643110. PMID 31184570.
  2. ^ a b c d e f "Viral Zone". ExPASy. Retrieved 15 June 2015.
  3. ^ Dolja, Valerian V (2001). "Capsid-Less RNA Viruses". Encyclopedia of Life Sciences. doi:10.1002/9780470015902.a0023269. ISBN 978-0470016176.
  4. ^ ICTVdB Management (2006). 00.108.0.01. Endornavirus. In: ICTVdB—The Universal Virus Database, version 4. Büchen-Osmond, C. (Ed), Columbia University, New York, USA.