Birnaviridae

Birnaviridae
Systematics
Classification : Viruses Area : Riboviria Empire : Orthornavirae Phylum : unclassified Order : unclassified Family : Birnaviridae
Taxonomic characteristics
Genome : dsRNA, 2 segments Baltimore : Group 3 Symmetry : icosahedral Cover : no
Scientific name
Birnaviridae
Left
NCBI  Taxonomy: 10993 ViralZone ( ExPASy , SIB): 162 ICTVdB Virus Code : 00.009

The family Birnaviridae comprises three genera of virus species with double-stranded RNA , which is similar to the family Partitiviridae in two segments. The family name is derived from the property of this segmentation (bi-RNA). The viruses of this family have no similarities in the nucleic acid sequence with other virus taxa. The VP4 protease of the Birnaviridae shows homologies to an ATP -dependent protease in bacteria and organelles . According to recent studies, there are similarities in the secondary structure of the viral RNA-dependent RNA polymerase (RdRP) of the Birnaviridae to members of the earlier family Tetraviridae (2011 by the International Committee on Taxonomy of Viruses (ICTV) divided into the families Alphatetraviridae , Carmotetraviridae and Permutotetraviridae . These findings allow the conclusion that the Birnaviridae belong to the oldest viruses in evolutionary terms .

Systematics

Internal system

The following breakdown into genera of the Birnaviridae follows the requirements of the International Committee on Taxonomy of Viruses (ICTV) as of November 2018,

• Family Birnaviridae
  • Genus Aquabirnavirus , in fish, molluscs and crustaceans , species:
    • Virus of the infectious pancreatic necrosis (en. Infectious pancreatic necrosis virus , IPNV), type species - causative agent of the infectious pancreatic necrosis of the salmonids d. H. Salmon fish
    • Yellowtail ascites virus ( en.Yellowtail ascites virus , YTAV)
    • Tellina virus (en. Tellina virus ), see Tellinoidea
  • Avibirnavirus genus in birds, species:
    • Infectious Bursitis virus (s. Infectious bursal disease virus , IBDV), only one so far, so type species
  • Genus Entomobirnavirus in insects, species:
    • Drosophila X virus (en. Drosophila X virus , DXV - see Drosophila ), so far the only one, therefore type species
  • Genus Blosnavirus , species:
    • Blotched snakehead virus (en. Blotched snakehead virus , BSNV - see snakehead fish: Channa maculata English Blotched snakehead ), so far the only one, therefore type species
• According to the proposal, the family also includes the following species that have not yet been assigned to any genus:
  • Species ' Rotifer Birnavirus ' (RBV)

External system

In 2015, Koonin et al assigned the Birnaviridae taxonomically (due to their relationship) to the supergroup 'Alphavirus-like superfamily' they postulated. The families that were previously grouped together as ' Tetraviridae ' can be found in close relatives : Alphatetraviridae , Carmotetraviridae and Permutotetraviridae (not yet distinguished by the authors). The members of this proposed supergroup belong to different groups in the Baltimore classification , usually single-stranded RNA viruses of positive polarity ((+) ssRNA, Baltimore group 4); however - like the Birnaviridae  - double-stranded representatives (marked with dsRNA, Baltimore group 3) can be found.

This suggestion has now been replaced by the ICTV Master Species List # 35 of March 2020. A comparison of the cladograms can be found in Tymovirales §ICTV Master Species List # 35 .

literature

• P. Dobos, BJ Hill, R. Hallett, DT Kells, H. Becht, D. Teninges: Biophysical and biochemical characterization of five animal viruses with bisegmented double-stranded RNA genomes . In: J Virology , 1979, 32 (2), pp. 593-605, PMID 228080 (with EM images)
• B. Delmas, FSB Kibenge et al .: Family Birnaviridae . In: CM Fauquet, MA Mayo et al .: Eighth Report of the International Committee on Taxonomy of Viruses . London San Diego 2004, p. 561 ff.

Individual evidence

1. ↑ ICTV Master Species List 2018b.v2 . MSL # 34, March 2019
2. ↑ ^{a b c d} ICTV: ICTV Master Species List 2019.v1 , New MSL including all taxa updates since the 2018b release, March 2020 (MSL # 35)
3. ↑ ^{a b} Master Species List 2018a v1 ICTV , MSL (# 33) including all taxa updates since the 2017 release. Fall 2018
4. ↑ AE Gorbalenya, FM Pringle, JL Zeddam, BT Luke, CE Cameron, J Kalmakoff, TN Hanzlik, KH Gordon, VK Ward: The palm subdomain-based active site is internally permuted in viral RNA-dependent RNA polymerases of an ancient lineage . In: J Mol Biol. , 2002, 15; 324 (1), pp. 47-62, PMID 12421558
5. ^ Michel Comps, Bruno Menu: Infectious diseases affecting mass production of the marine rotifer Brachionus plicatilis , in: Hydrobiologia, December 1997, Volume 358, Issue 1-3, pp. 179-183
6. ↑ Since this group (referred to by the authors as English superfamily ) contains an order with the Tymovirales , their rank must be higher than this and should not be understood as a superfamily . Ranks higher than order were not given by the ICTV at the time of the work.
7. ^ Eugene V. Koonin, Valerian V. Dolja, Mart Krupovic: Origins and evolution of viruses of eukaryotes: The ultimate modularity . In: Virology , May 2015, pp. 479-480. 2-25, Epub March 12, 2015, PMC 5898234 (free full text), PMID 25771806