Kakugo virus

Kakugo virus is a picorna-like virus most commonly found in the brains of worker bees. It is a subtype of the Deformed wing virus.^[1] The Kakugo (Japanese for 'ready to attack') virus, when resident in a bee's brain, can contribute to aggressive behaviors similar to those preeminent during a bee's guard phase in their life cycle. Kakugo virus is the first virus to be discovered that has been claimed to cause aggressive behavior.

Kakugo virus
Virus classification
(unranked):	Virus
Realm:	Riboviria
Kingdom:	Orthornavirae
Phylum:	Pisuviricota
Class:	Pisoniviricetes
Order:	Picornavirales
Family:	Iflaviridae
Genus:	Iflavirus
Species:	Deformed wing virus
Virus:	Kakugo virus

Analysis

Kakugo RNA encodes a protein of 2,893 amino acid residues that shares structural features and sequence similarities with various picorna-like virus polyproteins, especially those from sacbrood virus, which infects honeybees. The Kakugo protein contains several domains that correspond to the virion protein, helicase, protease, and RNA-dependent RNA polymerase domains of various picorna-like virus polyproteins.

Aggression

The increased aggression of infected Apis mellifera in Japan forces the bees to transmit, likely via Varroa. A. mellifera is sometimes known to show increased defence against Vespa mandarinia attacks and it has been suggested that this is due to Kakugo. However, a case was later found in which Kakugo virus infection spread throughout the nest, so it has been criticized that Kakugo virus infection does not influence the aggression of A. mellifera.