library_construction_protocol: RNA quality and quantity was measured by using nanodrop spectrophotometer (ND-1000, Nanodrop Technologies) and RNA Integrity was determined by gel electrophoresis Total RNA of each sample was used to prepare the RNA sequencing library 1)RNA fragment;2)Random primed first strand cDNA synthesis；3)dUTP based second strand cDNA synthesis;4)Adaptor ligation and PCR amplification.