Bracoviruses

Bracoviruses are a genus of large, double-stranded DNA viruses that infect insects, primarily belonging to the order Hymenoptera, specifically parasitic wasps. These viruses are obligate endosymbionts of their insect hosts and are transmitted vertically from mother to offspring. Bracoviruses are notable for their complex, often rod-shaped virions, which contain a large genome. The replication cycle of bracoviruses is intricate, relying on the host cell machinery and, in some cases, co-infection with a helper virus from the family Polydnaviridae.

The genome of bracoviruses is segmented and encodes a variety of genes, many of which are involved in manipulating the host's immune system and physiology to ensure the survival and development of the wasp larvae. This manipulation is crucial for the parasitic wasp's ability to successfully parasitize a target insect. Bracoviruses do not typically cause overt disease symptoms in the adult wasp, but their presence is essential for the successful completion of the parasitic life cycle. Research into bracoviruses is ongoing, focusing on understanding their evolutionary relationships, the molecular mechanisms of their replication and pathogenesis, and their potential applications in biological control strategies.