design: Library preparation and next-gen sequencing (2  150 bp paired end reads) was performed on a NovaSeq 6000 instrument (Illumina). mRNA was enriched using oligo(dT) beads. rRNA was removed using the Ribo-Zero kit that leaves the mRNA. First, the mRNA is fragmented randomly by adding fragmentation buffer, then the cDNA is synthesized by using mRNA template and random hexamers primer, after which a custom second-strand synthesis buffer (Illumina), dNTPs, RNase H and DNA polymerase I are added to initiate the second-strand synthesis. Second, after a series of terminal repair, A ligation and sequencing adaptor ligation, the double-stranded cDNA library is completed through size selection and PCR enrichment.