Cells were lysed in sample buffer and boiled for 10 min. Equal amounts of samples were subjected to sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE). Proteins were electroblotted onto polyvinylidene difluoride membranes (immobilon P; Millipore). Western blot was performed as described previously [27] . The following primary antibodies were used: anti-RVFV [27] ; anti-NSs [48] 