title: system-2
design: RNA quality was verified on an Agilent 2100 BioAnalyzer (Agilent Technologies, Santa Clara, CA, USA). Quality control on raw sequence data was performed using the FastQC tool. To obtain high-quality, clean data for analysis, adaptor sequence trimming and removal of low-quality reads were performed. RNA expression levels were determined by reads per kilobase per million (RPKM) mapped reads using quartile normalization and per-condition dispersion.