library_construction_protocol: The total RNA of cells were extracted by GeneJet RNA Purification Kit (Thermo Scientific, K0732). According to the manufacturer's instructions. The Magna RIPTM RNA-Binding Protein Immunoprecipitation Kit (Millipore 17-700) was used to perform RNA immunoprecipitation (RIP). 1µg total RNA was prepared to generate a sequencing library by TruSeqTM RNA Library Prep Kit V2 (Illumina, RS-122-2002). For RIP-Seq library generation, rRNA was removed using the Ribo-offTM rRNA Depletion Kit (Vazyme N406).