(A) Small dsRNA does not induce SG formation. EGFP-OASL1–expressing cells stimulated under the conditions indicated at the left [no stimulation, poly(I:C), or sdsRNA] were stained for SG with anti-TIAR antibody (red). Nuclei were stained with DAPI (blue). Scale bars correspond to 10 μm. (B) Reduced induction of cytokines by short double-strand RNA (sdsRNA). Wild-type BMMs were transfected with 1 μg/ml poly(I:C) or 100 nM sdsRNA for 3 or 9 h. Levels of Oasl1, Ifnα, Ifnβ, and Tnfα mRNAs were measured by qRT-PCR and normalized against the level of Gapdh mRNA in the same sample. Data represent means ± SD. Statistical significance was determined with the Student’s t-test. *P < 0.05, **P < 0.01. (C) Protein levels of OASL1 and IRF7 in Oasl1+/+ and Oasl1−/− BMMs stimulated with either poly(I:C) or sdsRNA. (D) The signal was measured by ImageJ software for each individual experiments and the graph represents the ratio of IRF7 signal intensity over OASL1 signal intensity. Each experiment was performed at least three times. Equal amounts of cytoplasmic extracts were analyzed by western analysis using the antibodies indicated at the left.