B2 protein from betanodavirus is expressed in recently infected but not in chronically infected fish.

Betanodavirus infects both larvae and juvenile fish and can cause the disease viral encephalopathy and retinopathy (VER). During an acute outbreak of VER, infected individuals display several clinical signs of infection, i.e.

RNA-dependent RNA polymerase from Atlantic halibut nodavirus contains two signals for localization to the mitochondria.

Nodaviruses encode an RNA-dependent RNA polymerase called Protein A that is responsible for replication of the viral RNA segments. The intracellular localization of Protein A from a betanodavirus isolated from Atlantic halibut (AHNV) was studied in infected fish cells and in transfected mammalian cells expressing Myc-tagged wild type Protein A and mutants. In infected cells Protein A localized to cytoplasmic structures resembling mitochondria and in transfected mammalian cells the AHNV Protein A was found to co-localize with mitochondrial proteins.