[The virus rabies protein: a multifonctional protein at the interface between the virus and its host]

Rhabdoviruses P protein plays a central role in the network of protein-protein interactions by providing a bridge at the interface between the polymerase L, N-RNAtemplate and cellulars factors. The P protein contains two independent binding sites : a N-terminal domain interacting with the L protein and a C-terminal domain which binds to the N-RNA. The P protein has two roles: it stabilizes the RNA polymerase L to the N-RNA template and binds to the soluble N^o preventing N aggregation and keeping N in a suitable form for specific encapsidation of viral RNA. The two cellular partners of rabies virus P protein identified until now do not seem to be involved in transcription and replication processes indicating that P may have others functions in the virus cycle. Interaction of P with the dynein light chain LC8 suggests that P could mediate the transport of viral nucleocapsids in the nervous central system. The interaction of P with the protein PML that is induced by interferon suggests that P may overcome the immune response of the infected cells. The multifonctionality of P is probably linked to the polymorphism of the protein which is characterized by the expression of shorter P forms in different cellular compartments and by the existence of various phosphorylated and oligomeric forms. The results are not sufficient to establish the involvement of this polymorphism on the various fonctions of P.