design: mRNA was purified from total RNA using poly-T oligo-attached magnetic beads. The cDNA fragments of ~240 bp in length were selected and further enriched with PCR amplification to generate cDNA libraries. At last, the library quality was assessed on the Agilent Bioanalyzer 2100 system. The clustering of the index-coded samples was performed on a cBot Cluster Generation System using TruSeq PE Cluster Kit v4-cBot-HS (Illumia) according to the manufacturers instructions. After cluster generation, the library preparations were sequenced on an Illumina platform and paired-end reads were generated.