mulberry transcriptome
First, poly-T oligo-attached magnetic beads were used to isolate poly (A) mRNA from the total RNA. The purified mRNA was then fragmented into small pieces (200–700 nt). The first strand of cDNA was synthesised using random hexamer primers, followed by synthesis of the second strand. The synthesized cDNA was subjected to end-repair and phosphorylation using T4 DNA polymerase, Klenow DNA polymerase and T4 PNK. The repaired cDNA fragments were 3’ adenylated using Klenow Exo-; Illumina’s paired-end adapters were ligated to the ends of these 3’-adenylated cDNA fragments. To select a size range of templates for downstream enrichment, the products of ligation reaction were purified on a 2% TAE-agarose gel. A range of cDNA fragments (200 * 25 bp) was excised from the gel. Fifteen rounds of PCR amplification were performed to enrich the purified cDNA template. The cDNA library was constructed with a fragment length range of 200 bp (*25 bp).