Illumina sequencing of CHO transcriptome (Control group, Day 6)
All libraries were prepared using the mRNA-Seq 8 sample prep Kit (Illumina, San Diego, CA USA) according to the manufacture’s instruction. In brief, first magnetic beads containing poly-T molecules were used to purify mRNA from 5 µg of total RNA. Second, samples were chemically fragmented and reverse transcribed into cDNA. Finally, end repair and A-base tailing was performed before Illumina adapters were ligated to the cDNA fragments. After a gel size fractionation step to extract fragments of approximately 200 bp, 30 µl of the purified samples were amplified by 15-cycle PCR. Amplified material was validated and quantified using an Agilent 2100 bioanalyzer and the DNA 1000 Nano Chip Kit (Agilent, Technologies, Santa Clara, CA, USA).  Libraries were loaded onto the channels of the flowcell at 5-7 pM concentration. Sequencing was carried out on the Genome Analyzer II (Illumina, San Diego, CA, USA) by running 36 cycles using Illumina’s Single Read Cluster Generation Kit and 36 Cycle Sequencing Kit according to the manufacturer’s instructions.