design: 1.Sample test included concentration, sample integrity and purification;2.Isolate mRNA from certain amount of total RNA by mRNA capture beads;3.Add GI tail to the end of mRNA and purified by magnetic beads;4.The total RNA was converted to full length cDNA by reverse transcription;5.Prepare the reaction system, incubate at propriate time for the DNA end repair;6.Prepare the adapter ligation system, incubate for a certain time to ligate the SMRTbell adapter with cDNA;7.Prepare the enzyme reaction system, incubate at a suitable temperature for a certain period of time to repair the damaged DNA and linear DNA without SMRTbell adapter;8.Library was qualified by QC.