Alphaherpesvirinae

Alphaherpesvirinae
Electron micrograph of a Human alphaherpesvirus 3 virion
Virus classification Edit this classification
(unranked): Virus
Realm: Duplodnaviria
Kingdom: Heunggongvirae
Phylum: Peploviricota
Class: Herviviricetes
Order: Herpesvirales
Family: Orthoherpesviridae
Subfamily: Alphaherpesvirinae
Genera

See text

Alphaherpesvirinae is a subfamily of viruses in the family Herpesviridae, primarily distinguished by reproducing more quickly than other subfamilies in the Herpesviridae. In animal virology the most important herpesviruses belong to the Alphaherpesvirinae. Pseudorabies virus is the causative agent of Aujeszky's disease in pigs and Bovine herpesvirus 1 is the causative agent of bovine infectious rhinotracheitis and pustular vulvovaginitis.[1][2] Mammals serve as natural hosts. There are currently 45 species in this subfamily, divided among 5 genera with one species unassigned to a genus. Diseases associated with this subfamily include: HHV-1 and HHV-2: skin vesicles or mucosal ulcers, rarely encephalitis and meningitis, HHV-3: chickenpox (varicella) and shingles, GaHV-2: Marek's disease.[3][4]

Genera

Alphaherpesvirinae consists of the following five genera:[4]

The species Chelonid alphaherpesvirus 6 is currently unassigned to a genus.[4]

Structure

Viruses in Alphaherpesvirinae are enveloped, with icosahedral, spherical to pleomorphic, and round geometries, and T=16 symmetry. The diameter is around 150-200 nm. Genomes are linear and non-segmented, around 120 to 180 kb in length.[3]

Genus Structure Symmetry Capsid Genomic arrangement Genomic segmentation
Iltovirus Spherical pleomorphic T=16 Enveloped Linear Monopartite
Mardivirus Spherical pleomorphic T=16 Enveloped Linear Monopartite
Simplexvirus Spherical pleomorphic T=16 Enveloped Linear Monopartite
Scutavirus Spherical pleomorphic T=16 Enveloped Linear Monopartite
Varicellovirus Spherical pleomorphic T=16 Enveloped Linear Monopartite

Life cycle

Viral replication is nuclear, and is lysogenic. Entry into the host cell is achieved by attachment of the viral gB, gC, gD and gH proteins to host receptors, which mediates endocytosis. Replication follows the dsDNA bidirectional replication model. DNA-templated transcription, with some alternative splicing mechanism is the method of transcription. Translation takes place by leaky scanning. The virus exits the host cell by nuclear egress, budding, and microtubular outwards viral transport. Mammals serve as the natural host. Transmission routes are sexual, contact, body fluids, lesions, and respiratory.[3]

Genus Host details Tissue tropism Entry details Release details Replication site Assembly site Transmission
Iltovirus Birds: galliform: psittacine None Cell receptor endocytosis Budding Nucleus Nucleus Oral-fecal; aerosol
Mardivirus Chickens; turkeys; quail None Cell receptor endocytosis Budding Nucleus Nucleus Aerosol
Simplexvirus Humans; mammals Epithelial mucosa Cell receptor endocytosis Budding Nucleus Nucleus Saliva
Scutavirus Sea turtles None Cell receptor endocytosis Budding Nucleus Nucleus Aerosol
Varicellovirus Mammals Epithelial mucosa Glycoproteins Budding Nucleus Nucleus Aerosol

References

  1. ^ Mettenleiter; et al. (2008). "Molecular Biology of Animal Herpesviruses". Animal Viruses: Molecular Biology. Caister Academic Press. ISBN 978-1-904455-22-6.
  2. ^ Sandri-Goldin RM., ed. (2006). Alpha Herpesviruses: Molecular and Cellular Biology. Caister Academic Press. ISBN 978-1-904455-09-7.
  3. ^ a b c "Viral Zone". ExPASy. Retrieved 12 June 2015.
  4. ^ a b c "Virus Taxonomy: 2020 Release". International Committee on Taxonomy of Viruses (ICTV). March 2021. Retrieved 10 May 2021.