The total RNAs were isolated from the cells by using TRIzol Reagent (Invitrogen, 15596018) following the manufacturer's mannual. Total RNA were extracted from cultured cells using Trizol. The mRNA libraries were then prepared using Collibri™ 3' mRNA Library Prep Kit for Illumina™ Systems (A38110024). The DNA libraries were then subjected to paired-end next-generation sequencing runs.