title: Transcriptomic analysis of a tertiary relict plant, extreme xerophyte Reaumuria soongorica to identify genes related to drought adaptation.
abstract: BACKGROUND
  Reaumuria soongorica is an extreme xerophyte shrub widely distributed in the desert regions including sand dune, Gobi and marginal loess of central Asia which plays a crucial role to sustain and restore fragile desert ecosystems. However, due to the lacking of the genomic sequences, studies on R. soongorica had mainly limited in physiological responses to drought stress. Here, a deep transcriptomic sequencing of R. soongorica will facilitate molecular functional studies and pave the path to understand drought adaptation for a desert plant.
  
  
  RESULTS
  A total of 53,193,660 clean paired-end reads was generated from the Illumina HiSeq™ 2000 platform. By assembly with Trinity, we got 173,700 contigs and 77,647 unigenes with mean length of 677 bp and N50 of 1109 bp. Over 55% (43,054) unigenes were successfully annotated based on sequence similarity against public databases as well as Rfam and Pfam database. Local BLAST and Kyoto Encyclopedia of Genes and Genomes (KEGG) maps were used to further exhausting seek for candidate genes related to drought adaptation and a set of 123 putative candidate genes were identified. Moreover, all the C4 photosynthesis genes existed and were active in R. soongorica, which has been regarded as a typical C3 plant.
  
  
  CONCLUSIONS
  The assembled unigenes in present work provide abundant genomic information for the functional assignments in an extreme xerophyte R. soongorica, and will help us exploit the genetic basis of how desert plants adapt to drought environment in the near future.
authors.affiliation: Key Laboratory of Stress Physiology and Ecology in Cold and Arid Regions, Department of Ecology and Agriculture Research, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Shi
authors.forename: Xia
authors.initials: X
authors.lastname: Yan
authors.forename: Pengshan
authors.initials: P
authors.lastname: Zhao
authors.forename: Hengxia
authors.initials: H
authors.lastname: Yin
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Honglang
authors.initials: H
authors.lastname: Xiao
authors.forename: Xinrong
authors.initials: X
authors.lastname: Li
authors.forename: Guoxiong
authors.initials: G
authors.lastname: Chen
authors.forename: Xiao-Fei
authors.initials: XF
authors.lastname: Ma
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D003681:Dehydration / Q000235:genetics / Q000378:metabolism; D055864:Droughts; D020869:Gene Expression Profiling; D063990:Gene Ontology; D017343:Genes, Plant; D058977:Molecular Sequence Annotation; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D013312:Stress, Physiological; D032363:Tamaricaceae / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D010940:Plant Proteins