Viral ion channels are short homo-oligomerizing small transmembrane
proteins usually expressed both in the viral envelope and/or host cell
membranes. They affect membrane permeability to ions and play an
important role either in facilitating virus entry, assembly and
release or modulating the ionic homeostasis of host cells. Viral ionic
channels are not necessarily required for the production of infectious
virions, although their expression usually significantly increases
growth.
Depending on the concerned virus, may:
- facilitate the uncoating of some viruses during entry.
- play a role during assembly by protecting viral glycoproteins from low pH during secretion
- facilitate virus budding.
| Family | Genus/species | Viral proteins | Reference | Function |
| Orthomyxoviridae | Influenzavirus A | M2 |
| Entry |
| Influenzavirus B | NB, BM2 | |
Entry | |
| Influenzavirus C | CM2 | |
Entry | |
| Flaviviridae | Hepacivirus | P7 |
|
?Assembly |
| Picornaviridae | Enterovirus | 2B |
| ? Release |
| * Togaviridae | Alphavirus | 6K |
|
Budding |
| * Retroviridae | Human immunodeficiency virus 1 | Vpu |
| Budding |
| Coronaviridae | Betacoronavirus | E |
|
Assembly |
| 3A |
|
Release | ||
| Phycodnaviridae | Chlorovirus | Kcv |
| Budding |
| Polyomaviridae | Polyomavirus | Agnoprotein |
|
Release |
- For those viruses, the channel activity has been shown in artificial lipid bilayers (ex-vivo) without linking it to functionality.