Denatured and re-natured pri-miRNA was mixed with recombinant protein at 4 °C for 1 h in EMSA buffer (10 mM Tris-HCl, pH 7.5, 150 mM KCl, 10% glycerol, 50 μg/ml poly[dI − dC] and RNase inhibitor). Bound complexes were resolved on 6% native polyacrylamide gels in 0.5 × ...