title: Transcriptomic analysis of Populustomentosa response to short-term salinity stress- 24h
design: The tissue-culturing seedlings of poplar were removed out of the tissue culture containers after eight-week cultivation and, subsequently, transferred to new containersin a gradually open environment in order to get acclimation. After two-week acclimation, the seedlings were treated with 200 mMNaCl for different time points of 0, 6, 12 and 24 h. Three biological replicates were prepared for each time point. the treated roots of two independently biological duplicates were frozen and stored in liquid nitrogen for total RNAs isolation.  RNA-seqlibraries were constructed according to the manuals as provided by Illumina and then sequenced on HiSeq2000. In brief,total RNAs were isolatedfrom roots according to the instruction of PLANTeasyextraction protocol (Beijing BLKW, China) and were thentreated with RNase-free DNase I (NEB, USA) to remove anycontaminating genomic DNA.mRNAs were purified from total RNAs using poly-T oligo-attached magnetic beads, and fragmented and used for cDNA synthesis with random hexamer primers and superscript II reverse transcriptase (Invitrogen, USA). After the purification of PCR products(AMPure XP system) and the assessment of library quality on the Agilent Bioanalyzer 2100 system, four paired-end cDNA libraries were sequenced using Illumina-solexa sequencing platform.