Down-regulation of BmPSI by RNAi increases female-specific splicing. (A) Schematic diagram of three dsRNAs (a, b, and c) specific for BmPSI. (B) NIAS-Bm-M1 cells were transfected with dsRNAs specific for DsRed (control), BmSqd2, BmELAV, or BmPSI. The upper panel shows the Bmdsx splicing pattern as detected by RT-PCR. Labels to the left of the gel refer to female splicing (Bmdsx F) and male splicing (Bmdsx M). The lower panel shows the specific down-regulation of BmSqd2, BmELAV, and BmPSI expression in dsRNA-treated cells. The RNA level of each gene was detected by RT-PCR using primers specific for each gene. (C) Quantification of the results derived from three independent experiments. Results are expressed as the percentage of RT-PCR products representing female or male splicing relative to total RT-PCR products.