Abstract Most microRNAs (miRNAs) are processed by two ribonuclease III enzymes. The first cleavage is performed Microprocessor that composed of RNase enzyme Drosha and DGCR8, the second another Dicer. There many examples miRNAs poor substrates for Dicer, owing to their suboptimal structures. However, a number these known be expressed at same or higher level as neighboring structurally-optimal m...