title: miRNA-seq of  sugarcane : root
design: For degradome library construction, polyadenylated  RNA was purified from 20 g total RNA of the mixed sample using poly-T oligo-attached magnetic beads. The 5 adapters were ligated to the 5 end of the 3 cleaved mRNA fragments from miRNA-induced cleavage by RNA ligase. The first strand of cDNA was reverse transcribed by random primers with a 3-adapter tag. After size selection with AMPureXP beads and cDNA amplification with polymerase chain reaction (PCR), a cDNA library with an average insert size of 200400 bp was prepared. Then, 50 bp single-end sequencing was performed on an Illumina Hiseq 2500 platform following the vendor's (LC Bio, China) recommended protocol at a depth of 20 million reads.