Cell pellets were resuspended in RLT and nucleic acids were extracted using the AllPrep DNA/RNA Mini Kit (QIAGEN catalog # 80204) according to the manufacturer's instructions. RNA was eluted in nuclease-free water and DNA in 0.5X Buffer EB. After RiboGreen quantification and quality control by Agilent BioAnalyzer, 125-500 ng of total RNA with RIN values of 8.3-10 underwent polyA selection and TruSeq library preparation according to instructions provided by Illumina (TruSeq Stranded mRNA LT Kit, catalog # RS-122-2102), with 8 cycles of PCR.