A novel nudivirus from the Jonah crab (Cancer borealis: Brachyura)

Nudiviruses are double stranded DNA viruses known to infect arthropod hosts. Around 20 different nudiviruses have been identified from crustacean hosts alone. In crustaceans, the hepatopancreas is the primary target of infection, where nuclei appear hypertrophic under histological preparation due to a growing intranuclear viroplasm. The Jonah crab, Cancer borealis, is the target species of an emerging fishery located in the New England (USA) region. Histological and metagenomic tools were used to characterize a new nudivirus, including pathological characterization and sequencing of the 97,677 bp genome, which encoded 93 open reading frames. The genome housed a genetic synteny that was similar to other gammanudiviruses. The virus also phylogenetically clusters with other members of the Gammanudivirus genus based on a 17-protein concatenated phylogenetic tree. Comparative genomics revealed up to 66 conserved genes across all Gammanudivirus species, including a putative deneddylase that appears not to be present in all other nudivirus lineages. Discovering and identifying this nudivirus provides greater detail on a new pathogen that poses a potential risk to the emerging fishery.