title: A transcriptomic analysis of Chrysanthemum nankingense provides insights into the basis of low temperature tolerance.
abstract: BACKGROUND
  A major constraint affecting the quality and productivity of chrysanthemum is the unusual period of low temperature occurring during early spring, late autumn, and winter. Yet, there has been no systematic investigation on the genes underlying the response to low temperature in chrysanthemum. Herein, we used RNA-Seq platform to characterize the transcriptomic response to low temperature by comparing different transcriptome of Chrysanthemum nankingense plants and subjecting them to a period of sub-zero temperature, with or without a prior low temperature acclimation.
  
  
  RESULTS
  Six separate RNA-Seq libraries were generated from the RNA samples of leaves and stems from six different temperature treatments, including one cold acclimation (CA), two freezing treatments without prior CA, two freezing treatments with prior CA and the control. At least seven million clean reads were obtained from each library. Over 77% of the reads could be mapped to sets of C. nankingense unigenes established previously. The differentially transcribed genes (DTGs) were identified as low temperature sensing and signalling genes, transcription factors, functional proteins associated with the abiotic response, and low temperature-responsive genes involved in post-transcriptional regulation. The differential transcription of 15 DTGs was validated using quantitative RT-PCR.
  
  
  CONCLUSIONS
  The large number of DTGs identified in this study, confirmed the complexity of the regulatory machinery involved in the processes of low temperature acclimation and low temperature/freezing tolerance.
authors.forename: Liping
authors.initials: L
authors.lastname: Ren
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Sumei
authors.initials: S
authors.lastname: Chen
authors.forename: Jiaojiao
authors.initials: J
authors.lastname: Gao
authors.forename: Bin
authors.initials: B
authors.lastname: Dong
authors.forename: Yanan
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Xia
authors.forename: Yinjie
authors.initials: Y
authors.lastname: Wang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liao
authors.forename: Nianjun
authors.initials: N
authors.lastname: Teng
authors.forename: Weimin
authors.initials: W
authors.lastname: Fang
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Guan
authors.affiliation: College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China. chenfd@njau.edu.cn.
authors.forename: Fadi
authors.initials: F
authors.lastname: Chen
authors.forename: Jiafu
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D002874:Chromosome Mapping; D031202:Chrysanthemum / Q000235:genetics*; D003080:Cold Temperature; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D017343:Genes, Plant; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018547:Plant Stems / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D017423:Sequence Analysis, RNA; D015398:Signal Transduction / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D059467:Transcriptome
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; D017346:Protein Serine-Threonine Kinases; D020929:Mitogen-Activated Protein Kinase Kinases