library_construction_protocol: 1ml TRIzol reagent was added to T150 flask and transferred to tubes. 0.2 mL of chloroform were added and aqueous phase containing the RNA were transferred to new tube after centrifugation. The RNA was then precipitated by isopropanol and washed by 75% ethanol. After washing the RNA was solubilized on 30ul RNase-free water and frozen at -80 degree immediately. Methods - Library prep: the sequin+total RNA mixtures were subjected to polyA selection (NEBNext PolyA E7490) and library prep (NEBNext Ultra II Directional RNA Library Prep Kit for Illumina) following manufacturer's instructions; we performed 9 PCR cycles