Molecular biology of borna disease virus: prototype of a new group of animal viruses.

Borna disease virus (BDV), the etiological agent of Borna disease (BD), causes a central nervous system disease that is manifested by profound behavioral abnormalities, accumulation of disease-specific antigens in limbic system neurons, and often, but not always, the presence of inflammatory cell infiltrates in the brain (35, 36, 47). BDV has been characterized recently as a nonsegmented, negative-stranded (NNS) RNA virus with the property, unique among NNS RNA animal viruses, of a nuclear site for replication and transcription of its genome, suggesting that BDV is the prototype of a new group of animal RNA viruses. Originally described in the early 19th century in horses in Germany, BD has become an important model for the study of both the mechanisms and the biological consequences of persistent virus infection of the central nervous system (35). Naturally occurring infections with BDV have been confirmed