FLIP-/- MEFs show enhanced NF-κB- and IRF3-induced gene expression in response to cytoplasmic dsRNA. A. Total RNA was isolated from WT and FLIP-/- MEFs 4 hours after they were either left untreated or treated with LF (8 μg/ml) + poly(I:C) (6 μg/ml). RNA was isolated, reverse-transcribed, and mRNA levels of il6, ifnb or ifna4 were quantified by RT-PCR with respect to gadph as an endogenous control. The data are representative of three experiments with similar findings. *p < 0.05 compared to WT. B. Wild type and FLIP-/- MEFs were either left untreated (lanes 1 and 3 respectively) or treated with LF/poly(I:C) (lanes 2 and 4 respectively) for 4 hrs. They were all treated with Brefeldin A (Golgiplug™) for 4 hours. Cell lysates were prepared and analyzed by immunoblot for IFN-β. The data are representative of two experiments with similar results.