Nudivirus

Nudivirus
Virus classification
Group:	Group I (dsDNA)
Family:	Unassigned
Genus:	Nudivirus
Species
Gryllus bimaculatus nudivirus Helicoverpa zea nudivirus 1 Helicoverpa zea nudivirus 2 Penaeus monodon nudivirus Oryctes rhinoceros nudivirus

Nudiviruses are large and rod-shaped viruses with a circular, double stranded DNA genome. They are related to the baculoviruses and like these infect arthropods, particularly insects (Wang et. al., 2007a^[1]). They share 20 core genes with baculoviruses. However, they are currently no longer regarded as members of the family Baculoviridae and are considered to be a sister group of these (Mayo, 1995^[2]).

Taxonomy

In 2007, the genus Nudivirus has been proposed to include viruses similar to the Oryctes rhinoceros virus (Wang et. al., 2007b^[3]).

Virology

This genus is characterized by rod-shaped and enveloped nucleocapsids and its members replicate in the nucleus of infected host cells. However, the viruses are not embedded in inclusion bodies (crystallized proteins) like the baculoviruses. All sequenced nudiviruses have 33 open reading frames in common, 20 of them are homologous to baculovirus core genes involved in RNA transcription, DNA replication, virion structural components and other functions. Nudiviruses and baculoviruses appear to be derived from a common ancestor and evolutionarily related to other large DNA viruses (Wang et. al., 2009^[4]).

Host-virus relations

• Gryllus bimaculatus nudivirus - black cricket (Teleogryllus commodus)
• Helicoverpa zea nudivirus 1 - cotton bollworm
• Helicoverpa zea nudivirus 2 - cotton bollworm
• Penaeus monodon nudivirus - a shrimp
• Oryctes rhinoceros nudivirus - rhinoceros beetle (Dynastinae species)

Relation to polydnaviruses in parasitic wasps

Parasitic wasps contain particles of polydnaviruses from portions of a nudivirus which have become part of the wasp genome. The genes help form particles like virions which are injected into the host larvae of the wasp and suppress a defensive response. The wasp eggs can then develop and parasitize the larva  (Stoltz et al., 2009^[5]).

References

1. ^ Wang, Yong-Jie; Burand, John P. & Jehle, Johannes A. (2007). "Nudivirus genomics: diversity and classification". Virologica Sinica 22 (2): 128–136. doi:10.1007/s12250-007-0014-3. http://www.virol.cn/qikan/manage/wenzhang/2007-2864.pdf. 
2. ^ Mayo, M.A. (1995). Murphy, F.A.; Fauquet, C.M.; Bishop, D.H.L.; et al.. ed. Unassigned Viruses. In: Virus Taxonomy: The Sixth Report of the International Committee on Taxonomy of Viruses. Springer-Verlag, Wien. pp. 504–507. 
3. ^ Wang, Y.; van Oers, M.M.; Crawford, A.M.; Vlak, J.M. & Jehle, J.A. (2007). "Genomic analysis of Oryctes rhinoceros virus reveals genetic relatedness to Heliothis zea virus 1". Archives of Virology 152 (3): 519–531. doi:10.1007/s00705-006-0872-2. PMID 17106621. 
4. ^ Wang, Yongjie & Jehle, Johannes A. (2009). "Nudiviruses and other large, double-stranded circular DNA viruses of invertebrates: New insights on an old topic". Journal of Invertebrate Pathology 101 (3): 187–193. doi:10.1016/j.jip.2009.03.013. PMID 19460388. 
5. ^ Donald B. Stoltz & James B. Whitfield (2009). "Making nice with viruses". Science 323 (5916): 884–885. doi:10.1126/science.1169808. PMID 19213903. http://www.sciencemag.org/cgi/content/short/323/5916/884.