Orthohepevirinae
Subfamily of viruses
From Wikipedia, the free encyclopedia
Orthohepevirinae is a subfamily of viruses assigned to the family Hepeviridae.[1][2] Viruses in the subfamily, called orthohepeviruses, have virions that are characterized by round, non-enveloped and isometric capsids with a diameter of 27–34 nm. The hepatitis E virus belongs to this subfamily as the species Paslahepevirus balayani.[1][2]
| Orthohepevirinae | |
|---|---|
| |
| TEM micrograph of Hepatitis E virus virions | |
Virus classification  | |
| (unranked): | Virus |
| Realm: | Riboviria |
| Kingdom: | Orthornavirae |
| Phylum: | Kitrinoviricota |
| Class: | Alsuviricetes |
| Order: | Hepelivirales |
| Family: | Hepeviridae |
| Subfamily: | Orthohepevirinae |
Genome
Orthohepeviruses have RNA genomes of 7176 nucleotides in length and infect vertebrates. Additionally, the genome is monopartite, linear, and single-stranded. The genome is 5' capped with a poly A tail at the 3' end. The genome possesses three main open reading frames. The first encodes non-structural proteins, the second encodes the capsid proteins, and the third encodes a small, multifunctional protein.[1]
Hosts
Evolution
One study has suggested that hepeviruses may have originated in birds and then spread to bats and other mammalian species.[3]
Taxonomy
The subfamily contains the following genera:[2]
- Avihepevirus
- Chirohepevirus
- Paslahepevirus, which contains Hepatitis E virus
- Rocahepevirus
History
Hepatitis E was first isolated in 1990. It was thought to be restricted to humans until 1997 when it was isolated from pigs.[6] The first isolation from birds was in 2001.[7]
The subfamily shares the name (Orthohepe-) of the former genus Orthohepevirus. This genus was abolished and orthohepeviruses were promoted to the rank of subfamily in 2022 with the establishment of the subfamily that year.[8][9]