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The total RNA of each sample was extracted with the RNAprep pure tissue kit following the manufacturers protocol. The integrity of the RNA was estimated by 1 % agarose gel electrophoresis, and the concentration and purity were determined with by the Bioanalyzer 2100 system. The high-quality RNA was used for the sequencing library construction with a NEBNext Ultra Directional RNA Library Prep Kit for Illumina, according to the instruction. Briefly, ribosomal RNA (rRNA) was first removed from the total RNA, and then the RNA was fragmented. Followingly, the first cDNA strand was synthesized with random hexamer primers and reverse transcriptase, and the second cDNA strand synthesized with DNA polymerase I and RNase H. After terminal repair, 3 terminal adenosylation and adaptor ligation, cDNA fragments with 250-300 bp were selected for polymerase chain reaction (PCR). Finally, a total of six sequencing libraries were constructed. The quality of the libraries was evaluated by the Agilent 2100 Bioanalyzer, and then subjected to 150 bp paired-end sequencing on the Illumina NovaSeq 6012 platform. All the sequencing data are deposited at the National Center for Biotechnology Information (NCBI) Sequence Read Archive (SRA) platform with accession no.