Borna disease virus: a unique pathogen and its interaction with intracellular signalling pathways.

Borna disease virus (BDV) is a neurotropic RNA virus that establishes non-cytolytic persistent infection in the central nervous system of warm-blooded animals. Depending on the host species and the route of infection, BDV persistence can modulate neuronal plasticity and animal behaviour and/or may provoke a T cell-mediated immunopathological reaction with high mortality. Therefore, BDV functions as a model pathogen to study persistent virus infection in the central nervous system. Here, we review recent evidence showing that BDV interferes with a spectrum of intracellular signalling pathways, which may be involved in viral spread, maintenance of persistence and modulation of neurotransmitter pathways.