FIG. 1.

Expression of the Nipah virus V protein inhibits IFN-α and IFN-γ signaling. (A) Human fibrosarcoma 2FTGH cells were transfected with empty vector (lane C) or expression vectors for HA-tagged SV5 V (lane SV), HPIV2 V (lane HV), or Nipah V (lane NV), and lysates were separated by SDS-PAGE (12% polyacrylamide). V proteins were visualized by immunoblotting with antiserum to the HA epitope tag. (B) 2FTGH cells were transfected with an ISRE-luciferase reporter gene and either empty vector, SV5 V (SV), or Nipah V (NV) expression vectors as indicated. The cells were treated with 1,000 U of IFN-α per ml 8 h prior to lysis and luciferase assays (+) or left untreated (−). (C) Same as in panel B but using an IFN-γ-responsive GAS-luciferase reporter gene and treatment with 5 ng/ml of IFN-γ (or no treatment). All bars represent average values from triplicate samples, normalized to cotransfected CMV-LacZ and expressed as percentages of IFN stimulated controls; error bars indicate standard deviations.