Picobirnavirus

From Infogalactic: the planetary knowledge core
(Redirected from Picobirnaviridae)
Jump to: navigation, search
Picobirnavirus
Virus classification
Group:
Group III (dsRNA)
Family:
Picobirnaviridae
Genus:
Picobirnavirus
Type Species

Lua error in Module:Taxonbar/candidate at line 22: attempt to index field 'wikibase' (a nil value).

Picobirnavirus is a genus of dsRNA viruses, the only genus in the family Picobirnaviridae. Amniotes, especially mammals, serve as natural hosts. There are currently only two species in this genus including the type species Human picobirnavirus. Diseases associated with this genus include: gastroenteritis in animals and humans, but the disease association is unclear.[1][2]

History

First detection of Picobirnavirus (PBV) was in humans and black-footed pigmy rice rats in 1988.[3]

Life Cycle

Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the double-stranded RNA virus replication model. Double-stranded RNA virus transcription is the method of transcription. Mammals serve as the natural host. Transmission routes are fecal-oral.[1]

Genus Host Details Tissue Tropism Entry Details Release Details Replication Site Assembly Site Transmission
Picobirnavirus Mammals Intestine (enteric) Unknown Budding Unknown Unknown Fecal-oral

Structure

Viruses in Picobirnavirus are non-enveloped, with icosahedral geometries, and T=3 symmetry. The diameter is around 35-40 nm.[1]

Genus Structure Symmetry Capsid Genomic Arrangement Genomic Segmentation
Picobirnavirus Icosahedral T=3 Non-Enveloped Linear Segmented

Genome

The genome is linear, bipartate, and double stranded RNA. It includes a segment 1 – 2.5 (2.2–2.7) kilobases (kb) length and a segment 2 – 1.7 (1.2–1.9) kb in length. The genome codes for 3 to 4 proteins.[1] The capsid protein gene is encoded by the second open reading frame of the larger genomic segment.

These viruses are divided into two genogroups on the basis of the sequence of segment 2.

They have been isolated from humans and other mammals, as well as birds and squamates.[4] Their role in pathogenicity if any is not yet clear.

Classification

PBV was initially thought to belong to family Birnaviridae but later confirmed to differ with respect to host, virion size, capsid, RNA polymerase, genome size, and organization. Now PBV has been classified distinctly[5] A new viral family named Picobirnaviridae under the proposed order Diplornavirales was created to accommodate this unique virus and a complete new taxonomic order was assigned [1]. This new viral family is composed of only one viral genus, Picobirnavirus. The two species under the genus are Human Picobirnavirus and Rabbit Picobirnavirus, where the former one is nominated as a type species and the latter one was designated species by the International Committee on Taxonomy of Viruses in 2008. The nomenclature of the virus has been derived from its size and genome characteristics: the prefix “pico” signifies the small diameter of the viral particle (35 nm) and “birna” signposts a genome composed of two segments of dsRNA.

Taxonomy

Group: dsRNA

Order: Unassigned

[2]

References

  1. 1.0 1.1 1.2 1.3 Lua error in package.lua at line 80: module 'strict' not found.
  2. 2.0 2.1 Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. Lua error in package.lua at line 80: module 'strict' not found.

External links