A NOVEL PRD-I AND TG BINDING-ACTIVITY INVOLVED IN VIRUS-INDUCED TRANSCRIPTION OF IFN-A GENES

Comparative analysis of the inducible elements of the mouse interferon A4 and A11 gene promoters (IE-A4 and IE-A11) by transient transfectio n experiments, DNase I footprinting and electrophoretic mobility shift assays resulted in identification of a virus-induced binding activity suggested to be involved in NBV-induced activation of transcription o f these genes, The virus-induced factor, termed VIF, is activated earl y by contact of virions with cells, It specifically recognizes the PRD I-like domain shared by both inducible elements, as well as the TO-li ke domain of IE-A4, This factor, distinct from the IRF-1, IRF-2 and th e alpha F1 binding proteins and presenting a different affinity patter n from that of the TG protein, is proposed as a candidate for IFN-type I gene regulation.