title: Exploration for the salt stress tolerance genes from a salt-treated halophyte, Suaeda asparagoides.
abstract: Salinity stress severely affects plant growth and development causing crop loss worldwide. Suaeda asparagoides is a salt-marsh euhalophyte widely distributed in southwestern foreshore of Korea. To isolate salt tolerance genes from S. asparagoides, we constructed a cDNA library from leaf tissues of S. asparagoides that was treated with 200 mM NaCl. A total of 1,056 clones were randomly selected for EST sequencing, and 932 of them produced readable sequence. By sequence analysis, we identified 538 unigenes and registered each in National Center for Biotechnology Information. The 80 salt stress related genes were selected to study their differential expression. Reverse transcription-PCR and Northern blot analysis revealed that 23 genes were differentially expressed under the high salinity stress conditions in S. asparagoides. They are functionally diverse including transport, signal transduction, transcription factor, metabolism and stress associated protein, and unknown function. Among them dehydrin (SaDhn) and RNA binding protein (SaRBP1) were examined for their abiotic stress tolerance in yeast (Saccharomyces cerevisiae). Yeast overexpressing SaDhn and SaRBP1 showed enhanced tolerance to osmotic, freezing and heat shock stresses. This study provides the evidence that SaRBP1 and SaDhn from S. asparagoides exert abiotic stress tolerance in yeast. Information of salt stress related genes from S. asparagoides would contribute for the accumulating genetic resources to improve osmotic tolerance in plants.
authors.affiliation: BK21 Center for Silver-Bio Industrialization, College of Natural Resources and Life Science, Dong-A University, Busan, Republic of Korea.
authors.forename: Selvam
authors.initials: S
authors.lastname: Ayarpadikannan
authors.forename: Eunsook
authors.initials: E
authors.lastname: Chung
authors.forename: Chang-Woo
authors.initials: CW
authors.lastname: Cho
authors.forename: Hyun-Ah
authors.initials: HA
authors.lastname: So
authors.forename: Soon-Ok
authors.initials: SO
authors.lastname: Kim
authors.forename: Joo-Min
authors.initials: JM
authors.lastname: Jeon
authors.forename: Myoung-Hae
authors.initials: MH
authors.lastname: Kwak
authors.forename: Seon-Woo
authors.initials: SW
authors.lastname: Lee
authors.forename: Jai-Heon
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000220:Adaptation, Biological; D000595:Amino Acid Sequence; D019663:Chenopodiaceae / Q000235:genetics*; D018076:DNA, Complementary; D020224:Expressed Sequence Tags; D018506:Gene Expression Regulation, Plant; D007723:Korea; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000235:genetics; D054712:Salinity; D055049:Salt Tolerance / Q000235:genetics*; D055051:Salt-Tolerant Plants / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D016601:RNA-Binding Proteins; D014157:Transcription Factors