library_construction_protocol: Total RNA was isolated using RNeasy Mini Kit (Qiagen) following the manufacturer's protocol. DNase I in column digestion was included to ensure the RNA quality. RNA library preparation was performed by using NEBNext® Ultra™ Directional RNA Library Prep Kit for Illumina (E7420L). Paired-end sequencing was performed with Illumina HiSeq platform at RiboBio Co., Ltd. or Amogene Biotech Co., Ltd.