title: mESC_bulk_Cas9
design: Total RNA was extracted from approximately one million mESCs using a                 miRNeasy Micro kit (QIAGEN). The libraries were constructed following the                 manufacturer's protocol using NEBNext kits (E7490&E7530), before PCR enrichment,                 the DNA was digested by Cas9 nuclease with sgRNA mix at 37 degree Celsius for                 2h