Cells were grown under the same conditions as in Figure 3C,G, then lysed and immunoprecipitated with either no antibody or monoclonal antibody J2 against double stranded RNA (dsRNA). Quantitative RT-PCR was used to quantify MAL32 or GAL4, L-A (a dsRNA produced by Killer virus) and ACT1 in each fraction. Signals were normalized to ACT1, which should produce minimal dsRNA under normal conditions. For quantification, n = 3 biological replicates, error bars represent ±1se, *p<0.05, ***p<0.01 by Student’s t test, data were log transformed for t test to avoid issues caused by the very large difference in dsRNA quantification between wt and RNAi+ cells, y axes in arbitrary units. The significant differences in the no antibody controls match the difference in the total lysates and reflect non-specific RNA binding.