A similar, albeit less dramatic, induction and suppression of MDA-5 expression was also observed (Fig. 8D) , which indicated that MDA-5 might also be an intermediate adaptor bridging the MAP kinases ERK1/2 and JNK1/2 to the NFkB pathway activation. The cells were pretreated with U0126, SB230058, and InSolution JNK inhibitor, 1 hr before H1N1pdm infection. Total RNA was prepared from infected cells for reverse transcription. cDNA was used for realtime PCR with RIG-1 and MDA-5 primers to measure fold changes of RIG-1 and MDA-5 transcripts in treated swine macrophages. Each assay was repeated at least twice. Data show mean fold change plus standard deviation of two or three independent assays. *p,0.05, Student's t-test. doi:10.1371/journal.pone.0030328.g008