Orthohepadnavirus

Orthohepadnavirus
TEM micrograph showing Hepatitis B virus virions
Virus classification
(unranked): Virus
Realm: Riboviria
Kingdom: Pararnavirae
Phylum: Artverviricota
Class: Revtraviricetes
Order: Blubervirales
Family: Hepadnaviridae
Genus: Orthohepadnavirus
Species

See text

Orthohepadnavirus is a genus of viruses, in the family Hepadnaviridae.[1] Humans and other mammals serve as natural hosts. There are 19 species in this genus.[1] Diseases associated with this genus include: hepatitis, hepatocellular carcinoma (chronic infections), and cirrhosis.[1][2]

Taxonomy

The genus contains the following species, listed by scientific name and followed by the exemplar virus of the species:[3]

  • Orthohepadnavirus bassarisci, Ringtail hepatitis B virus
  • Orthohepadnavirus equidae, Equid hepatitis B virus
  • Orthohepadnavirus felisdomestici, Domestic cat hepatitis B virus
  • Orthohepadnavirus hominoidei, Hepatitis B virus genotype D
  • Orthohepadnavirus lagothricis, Woolly monkey hepatitis B virus
  • Orthohepadnavirus longidigiti, Long-fingered bat hepatitis B virus
  • Orthohepadnavirus magniferrequini, Greater Horseshoe bat hepatitis B virus
  • Orthohepadnavirus magnimyotis, Large myotis bat hepatitis B virus
  • Orthohepadnavirus marmotae, Woodchuck hepatitis virus
  • Orthohepadnavirus myominrhinus, Myodav bat hepatitis B virus
  • Orthohepadnavirus philantombae, Tai Forest hepatitis B virus
  • Orthohepadnavirus pomi, Pomona bat hepatitis B virus
  • Orthohepadnavirus rotundifolii, Roundleaf bat hepatitis B virus
  • Orthohepadnavirus sapaji, Capuchin monkey hepatitis B virus
  • Orthohepadnavirus sciuri, Ground squirrel hepatitis virus
  • Orthohepadnavirus soricicoronati, Crowned shrew hepatitis B virus
  • Orthohepadnavirus soriciodoris, Musk shrew hepatitis B virus
  • Orthohepadnavirus soricisinensis, Chinese shrew hepatitis B virus
  • Orthohepadnavirus tabernarii, Tent-making bat hepatitis B virus

Structure

Viruses in the genus Orthohepadnavirus are enveloped, with spherical geometries, and T=4 symmetry. The diameter is around 42 nm. Genomes are circular, around 3.2kb in length. The genome codes for 7 proteins.[1][2]

Genus Structure Symmetry Capsid Genomic arrangement Genomic segmentation
Orthohepadnavirus Icosahedral T=4 Non-enveloped Circular Monopartite

Life cycle

Viral replication is nucleo-cytoplasmic. Replication follows the dsDNA(RT) replication model. DNA-templated transcription, specifically dsDNA(RT) transcription, with some alternative splicing mechanism is the method of transcription. Translation takes place by leaky scanning. The virus exits the host cell by budding, and nuclear pore export. Human and mammals serve as the natural host. Transmission routes are sexual, blood, and contact.[1][2]

Genus Host details Tissue tropism Entry details Release details Replication site Assembly site Transmission
Orthohepadnavirus Humans; mammals Hepatocytes Cell receptor endocytosis Budding Nucleus Cytoplasm Vertical: parental; sex; blood

References

  1. ^ a b c d e "ICTV Report Hepadnaviridae".
  2. ^ a b c "Viral Zone". ExPASy. Retrieved 15 June 2015.
  3. ^ "Virus Taxonomy: 2024 Release". International Committee on Taxonomy of Viruses. Retrieved 22 March 2025.