RVFV MP-12 or ZH501 NSs ORF, or CAT ORF were cloned downstream of the T7 promoter between the Kpn I and Xho I sites of the pcDNA3.1-myc-HisA (Invitrogen) plasmid. For rLuc RNA transcripts, the rLuc ORF in pRL-SV40 plasmid (Promega Corporation) was inserted downstream of the T7 promoter. Capped and polyadenylated RNA transcripts were synthesized in vitro by using mMESSAGE mMACHINE T7 Ultra (Ambion) according to the manufacturer's instructions [64] . One microgram of in vitrosynthesized RNA transcripts was transfected into 293 cells in a 12well plate with a TransIT-mRNA Transfection kit (Mirus Bio Corporation) according to the manufacturer's instructions.