Ectopic pri-miRNA expression in S2 cells: mock transfection
Total RNA from individual transfections was combined and libraries for small-RNA sequencing prepared as described (Chiang et al., 2010).  Briefly, 18-35 nt RNA was purified on a 15% polyacrylamide gel.  RNA was ligated to a preadenylated 3' adaptor.   The first six nucleotides of the 3' adaptor are TCGTAT.  After gel purification, the ligation products were ligated to the 5' adaptor.  After another round of gel purification, ligated RNA was reverse transcribed and amplified for Illumina high-throughput sequencing.