library_construction_protocol: RNA were extracted using TRIzol (Life Technologies). RNA quality was determined by examining A260/A280 with NanodropTM OneC spectrophotometer (Thermo Fisher Scientific Inc). RNA Integrity was confirmed by 1.5% agarose gel electrophoresis. Qualified RNAs were finally quantified by Qubit   3.0 with QubitTM RNA Broad Range Assay kit (Life Technologies, Q10210). 2 μg total RNAs were used for stranded RNA sequencing library preparation using KCTM Stranded mRNA Library Prep Kit for Illumina® (Catalog NO. DR08402, Wuhan Seqhealth Co., Ltd. China) following the manufacturer's instruction. PCR products corresponding to 200-500 bps were enriched and quantified, and finally sequenced on Novaseq 6000 sequencer (Illumina) with 150 bp paired-end reads.