Transcriptome profiling of Lonicera japonica reveals candidate genes in response to cold stress
Total RNA was extracted with Omega Plant RNA Kit (Omega Bio-tek, USA). Before cDNA library construction, the quality of RNA solutions was detected by Nanodrop (Thermo Scientific, USA), Qubit 2.0 (Thermo Scientific, USA), and Agilent 2100 (Agilent, USA) to ensure the RNA solutions fulfilling the standard for RNA-seq. Library preparation and sequencing experiments were performed according to the standard procedure provided by Illumina. mRNA was enriched with an NEB Next poly(A) mRNA Magnetic Isolation Module (NEB, USA), and a library was prepared with an NEB Next mRNA Library Prep Master Mix Set for Illumina and NEB Next Multiplex Oligos for Illumina. The insert size and concentration of the RNA library was detected by 1.8% agarose gel electrophoresis and qRT-PCR, respectively. Finally, qualified libraries were sequenced on an Illumina HiSeqTM 2500 system. Up to 6G of raw data were generated for each sample, with a Q30 of > 80%.