Total RNA was extracted using TRI Reagent (T9424, Merck) and quantified using NanoDrop (Thermo, ND 1000).  All samples with OD 260/280 ratio > 1.8 and OD 230/260 ratio > 2 were subjected to sequencing. Sequencing libraries were generated using KAPA mRNA HyperPrep Kit (KAPA Biosystems, Roche, Basel, Switzerland) following manufacturer's recommendations and index codes were added to attribute sequences to each sample.