IVT was performed using the ''TNT-T7 Quick Reticulocyte Lysate System'' kit (Promega) for 30 to 45 min (0.25-1 mg DNA per reaction). Then, aliquots of the reaction mix were treated with RNase B (1 mg/ml, Sigma) for 10 min and incubated with the probes as described below. SDS-PAGE followed by fluorography was performed as described [67] .