| Lavidaviridae | |
|---|---|
| |
| Sputnik virophage | |
Virus classification 
| |
| (unranked): | Virus |
| Realm: | Varidnaviria |
| Kingdom: | Bamfordvirae |
| Phylum: | Preplasmiviricota |
| Class: | Maveriviricetes |
| Order: | Priklausovirales |
| Family: | Lavidaviridae |
| Genera and species | |
The parasitic lifestyle of virophages [1]
(A) When the host cell is only infected by a giant virus, the latter establishes a cytoplasmic virus factory to replicate and generates new virions, and the host cell is most likely lysed at the end of its replication cycle.(B) When the host cell is co-infected with a giant virus and its virophage, the latter parasitizes the giant virus factory. The presence of virophages could seriously impact the infectivity of the giant virus by decreasing its replication efficiency and increasing the survival of the host cell.
(C) When the giant virus genome is parasitized by a provirophage, the latter is expressed during the giant virus replication. The virophage is produced from the giant virus factory and inhibits the giant virus replication, thus increasing the host cell survival.
VF: Virus factory
Virophages and satellite virus’ lifestyle [1]
(A) The replication of virophages is supposed to occur entirely in the virus factory of its giant virus host, depending on the giant virus expression/replication complex.(B) The concept of satellite virus implicates that the virus initiates the expression and replication of its genome in the nucleus using the host cell machinery and then goes to the cytoplasm. In the cytoplasm, the satellite virus hijacks the morphogenesis machinery of its helper virus to produce its progeny.
Virophages are small, double-stranded DNA viral phages that require the co-infection of another virus. The co-infecting viruses are typically giant viruses. Virophages rely on the viral replication factory of the co-infecting giant virus for their own replication. One of the characteristics of virophages is that they have a parasitic relationship with the co-infecting virus. Their dependence upon the giant virus for replication often results in the deactivation of the giant viruses. The virophage may improve the recovery and survival of the host organism.
All known virophages are grouped into the family Lavidaviridae (from "large virus dependent or associated" + -viridae).[2]
- ^ a b Mougari, S., Sahmi-Bounsiar, D., Levasseur, A., Colson, P. and La Scola, B. (2019) "Virophages of Giant Viruses: An Update at Eleven". Viruses, 11(8): 733. doi:10.3390/v11080733.
Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License
- ^ Duponchel, S; Fischer, MG (March 2019). "Viva lavidaviruses! Five features of virophages that parasitize giant DNA viruses". PLOS Pathogens. 15 (3): e1007592. doi:10.1371/journal.ppat.1007592. PMC 6428243. PMID 30897185.
