Protoparvovirus

Protoparvovirus
Virus classification
Group: Group II (ssDNA)
Family: Parvoviridae
Subfamily: Parvovirinae
Genus: Protoparvovirus
Type Species

Protoparvovirus is a genus of viruses in the subfamily Parvovirinae of the virus family Parvoviridae. Vertebrates serve as natural hosts. There are currently five species in this genus including the type species Rodent protoparvovirus 1. This genus includes canine parvovirus, which causes gastrointestinal tract damage in puppies that is about 80% fatal.[1][2] Until 2014, the genus was called Parvovirus, but it was renamed to eliminate confusion between members of this genus and members of the entire family Parvoviridae.[3][4]

Taxonomy

Group: ssDNA

[2]

Five species are currently recognized, most containing several named viruses, virus strains, genotypes or serotypes. When applied to viruses, the definition of species is a little unusual.[5] It is simply an abstract taxonomic concept that clusters a selected range of genetic variants, helping to distinguish branches in a phylogenetic lineage, but it is not a physical entity like a virus that can infect an animal or be isolated.[6] If the diversity level used to define a species is set very low, many will effectively contain a single virus, and the virus and species may even be given the same name, resulting in confusion between the two concepts in the literature, and marginalizing the phylogenetic role of the species taxon. To counter this problem, the diversity level now recognized for species in the Parvoviridae is relatively broad: species are defined as a cluster of similar viruses that encode a particular replication protein, typically called NS1, that is at least 85% identical to the protein encoded by other members of the species, as discussed in [3] and.[4]

Recognized species in genus Protoparvovirus include:

Another candidate virus in this group - Tusavirus 1 - has been reported in the feces of a single human, but whether or not it is able to infect humans or was simply ingested remains to be clarified.[7]

Structure

Viruses in genus Protoparvovirus have non-enveloped protein capsids around 18-26 nm in diameter, which show T=1 icosahedral symmetry. Genomes are single-stranded linear DNA between 4-6kb in length, with small (100-500b) imperfect palindromic sequences at each terminus that fold to form distinctive duplex hairpin telomeres.[1]

Genus Structure Symmetry Capsid Genomic Arrangement Genomic Segmentation
ProtoparvovirusIcosahedralT=1Non-EnvelopedLinear ssDNANo

Life Cycle

Viral replication is nuclear. Entry into the host cell is achieved by attachment to host receptors, which mediates clathrin-mediated endocytosis. Replication follows the rolling-hairpin model. In some virus/host cell combinations, progeny virions can be trafficked through the cytoplasm in vesicles and released from the parental host cell prior to cell death, while the remaining virions are released following cell lysis. Vertebrates from 4 orders are currently known to serve as natural hosts. Transmission routes are fecal-oral and/or respiratory.[1]

Genus Host Details Tissue Tropism Entry Details Release Details Replication Site Assembly Site Transmission
ProtoparvovirusVertebratesVariableendocytosisearly vesicular export/cell lysisNucleusNucleusfecal-oral or respiratory

History

Kilham rat virus, isolated in 1959,[8] was the first member of this family of small, linear, single-stranded DNA viruses to be identified.

In following years a series of physically similar viruses, including H1, LuIII, minute virus of mice and tumor virus X, were extracted from cells or tissues in routine use in research laboratories[9] and porcine parvovirus, PPV, one of the major causes of reproductive failure in swine, was isolated from infected pigs.[10] In 1971 these viruses were all recognized as part of a taxonomic genus called Parvovirus in the First Report of the newly created International Committee on Taxonomy of Viruses (ICTV)[11]

The Second ICTV Report, published in 1976, established the family Parvoviridae, which at that time included three genera, one of which retained the name Parvovirus and contained all of the aforementioned viruses plus feline panleukopenia virus (now called feline parvovirus, abbreviated to FPV), which had been shown to cause epidemics of enteritis, panleukopenia and congenital cerebellar ataxia in domestic cats. In 1978 a virus from the same species as FPV emerged that was able to infect dogs (called canine parvovirus or CPV), which rapidly spread globally, causing pandemics of severe intestinal and coronary disease.[12]

Genus Parvovirus continued to accrue new viruses[13] until 2014, when its name was changed to Protoparvovirus.

A new virus in this genus was recently discovered in the feces of children from Burkina Faso, and named using the siglum Bufavirus.[14] Three genotypes of bufaviruses have so far been detected, circulating in Tunisia, Finland[15] and Bhutan[16]

References

  1. 1 2 3 "Viral Zone". ExPASy. Retrieved 15 June 2015.
  2. 1 2 ICTV. "Virus Taxonomy: 2014 Release". Retrieved 15 June 2015.
  3. 1 2 "ICTV Official Taxonomy: Updates since the 8th Report". ICTV Official Taxonomy. ICTV Official Taxonomy. Retrieved 11 June 2014.
  4. 1 2 Cotmore SF, Agbandje-McKenna M, Chiorini JA, Mukha DV, Pintel DJ, Qiu J, Soderlund-Venermo M, Tattersall P, Tijssen P, Gatherer D, Davison AJ. 2014. The family Parvoviridae. Arch. Virol. 159: 1239—47.
  5. ↑ Van Regenmortel MHV (2000) Introduction to the species concept in virus taxonomy. In: Van Regenmortel MHV, Fauquet CM, Bishop DHL, Carstens EB, Estes MK, Lemon SM, McGeogh DJ, Maniloff J, Mayo MA, Pringle CR, Wickner RB. (eds) Virus Taxonomy-Seventh Report of the International Committee on Taxonomy of Viruses. Elsevier Academic Press, London.
  6. ↑ Van Regenmortel MHV (2003) Viruses are real, virus species are man-made taxonomic constructions. Arch. Virol. 148: 2481–2488.
  7. ↑ Phan TG, Sdiri-Loulizi K, Aouni M, Ambert-Balay K, Pothier P, Deng X, Delwart E (2014) New parvovirus in child with unexplained diarrhea, Tunisia. Emerg Infect Dis 20(11):1911-1913. doi: 10.3201/eid2011.140428
  8. ↑ Kilham, L. and Olivier, L. J. 1959. A latent virus of rats isolated in tissue culture. Virology 7: 428–37
  9. ↑ Tattersall, P. 2006. The evolution of parvovirus taxonomy. In: ‘‘The Parvoviruses’’. J. Kerr, S. F. Cotmore, M. E. Bloom, R. M. Linden, and C. R. Parrish (eds), Chap. 1, pp. 5–4. Hodder Arnold, London.
  10. ↑ Ren X, Tao Y, Cui J, Suo S, Cong Y, Tijssen P. 2013. Phylogeny and evolution of porcine parvovirus. Virus Research. 178:392-397.
  11. ↑ http://ictvonline.org/taxonomyReleases.asp
  12. ↑ Hoelzer K, Parrish CR. 2010. The emergence of parvoviruses of carnivores. Vet. Res. 41:39.
  13. ↑ Tijssen P, Agbandje-McKenna M, Almendral JM, Bergoin M, Flegel TW, Hedman K, Kleinschmidt J, Li Y, Pintel DJ, Tattersall P (2011) The family Parvoviridae. In: King AMQ, Adams MJ, Carstens EB, Lefkowitz EJ (eds) Virus taxonomy—Ninth Report of the International Committee on Taxonomy of Viruses. Elsevier/ Academic Press, London, pp 405–425.
  14. ↑ Phan TG, Vo NP, Bonkoungou IJ, Kapoor A, Barro N, O’Ryan M, Kapusinszky B, Wang C, Delwart E. 2012. Acute diarrhea in West African children: diverse enteric viruses and a novel parvovirus genus. J Virol. 86:11024–30
  15. ↑ Väisänen E, Kuisma I, Phan TG, Delwart E, Lappalainen M, Tarkka E, Hedman K, Söderlund-Venermo M. 2014. Bufavirus in feces of patients with gastroenteritis, Finland. Emerg Infect Dis. 20(6):1078-80.
  16. ↑ Yahiro T, Wangchuk S, Tshering K, Bandhari P, Zangmo S, Dorji T, Tshering K, Matsumoto T, Nishizono A, Söderlund-Venermo M, Ahmed K. 2014. Novel human bufavirus genotype 3 in children with severe diarrhea, Bhutan. Emerg Infect Dis. 20(6):1037-9.

External Links

This article is issued from Wikipedia - version of the Friday, August 28, 2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.