''Avihepadnavirus'' is a genus of

virus A virus is a submicroscopic infectious agent that replicates only inside the living Cell (biology), cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are ...

es, in the family ''

Hepadnaviridae ''Hepadnaviridae'' is a family of viruses. Humans, apes, and birds serve as natural hosts. The family contains five genera. Its best-known member is hepatitis B virus. Diseases associated with this family include: liver infections, such as hep ...

''. Birds serve as natural hosts. There are five species in this genus. Diseases associated with this genus include:

hepatitis Hepatitis is inflammation of the liver parenchyma, liver tissue. Some people or animals with hepatitis have no symptoms, whereas others develop yellow discoloration of the skin and whites of the eyes (jaundice), Anorexia (symptom), poor appetite ...

hepatocellular carcinoma Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide. HCC most common ...

s (chronic infections), and

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, chronic liver failure or chronic hepatic failure and end-stage liver disease, is a chronic condition of the liver in which the normal functioning tissue, or parenchyma, is replaced ...

Taxonomy

The genus contains the following species, listed by scientific name and followed by the exemplar virus of the species: * ''Avihepadnavirus anatigruidae'',

Duck hepatitis B virus Duck hepatitis B virus, abbreviated DHBV, is part of the genus '' Avihepadnavirus'' of the ''Hepadnaviridae'', and is the causal agent of duck hepatitis B. DHBV is a small DNA virus with a diameter of 40–45 nm. The viral envelope is ma ...

* ''Avihepadnavirus ciconiardeae'', Heron hepatitis B virus * ''Avihepadnavirus psittaunius'', Parrot hepatitis B virus 1 * ''Avihepadnavirus psittaduorum'', Parrot hepatitis B virus 2 * ''Avihepadnavirus bonicursoris'', Elegant-crested tinamou hepatitis B virus

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.

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.

References

External links

ICTV Report: ''Hepadnaviridae''

{{Taxonbar, from=Q842413 Hepadnaviridae Virus genera