Avihepadnavirus
Avihepadnavirus is a genus of viruses, in the family Hepadnaviridae.[1] Birds serve as natural hosts. There are three species in this genus including the type species Duck hepatitis B virus.[1] Diseases associated with this genus include: hepatitis, hepatocellular carcinomas (chronic infections), and cirrhosis.[2][3]
| Avihepadnavirus | |
|---|---|
Virus classification  | |
| (unranked): | Virus |
| Realm: | Riboviria |
| Kingdom: | Pararnavirae |
| Phylum: | Artverviricota |
| Class: | Revtraviricetes |
| Order: | Blubervirales |
| Family: | Hepadnaviridae |
| Genus: | Avihepadnavirus |
| Type species | |
| Duck hepatitis B virus | |
| Species | |
| |
Structure
Viruses in the genus Avihepadnavirus 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 |
|---|---|---|---|---|---|
| Avihepadnavirus | 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 ribosomal shunting. The virus exits the host cell by budding, and nuclear pore export. Birds serve as the natural host. Transmission routes are parental, sexual, and blood.[1][2]
| Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
|---|---|---|---|---|---|---|---|
| Avihepadnavirus | Birds | Hepatocytes | Cell receptor endocytosis | Budding | Nucleus | Cytoplasm | Vertical: parental; sex; blood |
References
- "ICTV Report Hepadnaviridae".
- "Viral Zone". ExPASy. Retrieved 12 June 2015.
- Guo, Haitao; Mason, William (2005). "Identification and Characterization of Avihepadnaviruses Isolated from Exotic Anseriformes Maintained in Captivity". Journal of Virology. American Society for Microbiology. 79 (5): 2729–2742. doi:10.1128/JVI.79.5.2729-2742.2005. PMC 548436. PMID 15708992.