FIG. 1.

RNAs from virus-infected cells act as RLR agonists. (A and B) MEFs of the indicated genotype were transfected with 0.2 μg of the indicated RNA, and accumulation of IFN-α in supernatants was measured by ELISA after overnight incubation. (B) MEFs of the indicated genotype were transfected with 0.2 μg of RNA from virus-infected cells. After overnight incubation, IFN-α/β in the supernatant was measured on indicator cells containing an ISRE-Luc reporter. (C) RNA from infected cells was treated with CIP (+) or buffer only (−) before transfection. IFN-α was measured by ELISA. Graphs show one of at least three representative experiments. Error bars show standard deviation of triplicate (A and C) or quadruplicate (B) measurements. Asterisks indicate a P value of <0.01 compared to wild-type (wt) control MEFs.