title: Discovery and characterization of two novel salt-tolerance genes in Puccinellia tenuiflora.
abstract: Puccinellia tenuiflora is a monocotyledonous halophyte that is able to survive in extreme saline soil environments at an alkaline pH range of 9-10. In this study, we transformed full-length cDNAs of P. tenuiflora into Saccharomyces cerevisiae by using the full-length cDNA over-expressing gene-hunting system to identify novel salt-tolerance genes. In all, 32 yeast clones overexpressing P. tenuiflora cDNA were obtained by screening under NaCl stress conditions; of these, 31 clones showed stronger tolerance to NaCl and were amplified using polymerase chain reaction (PCR) and sequenced. Four novel genes encoding proteins with unknown function were identified; these genes had no homology with genes from higher plants. Of the four isolated genes, two that encoded proteins with two transmembrane domains showed the strongest resistance to 1.3 M NaCl. RT-PCR and northern blot analysis of P. tenuiflora cultured cells confirmed the endogenous NaCl-induced expression of the two proteins. Both of the proteins conferred better tolerance in yeasts to high salt, alkaline and osmotic conditions, some heavy metals and H2O2 stress. Thus, we inferred that the two novel proteins might alleviate oxidative and other stresses in P. tenuiflora.
authors.affiliation: Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin Hexing Road, Harbin 150040, China. ly7966@163.com.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Asian Natural Environmental Science Center, University of Tokyo, Nishitokyo-shi, Tokyo 188-0002, Japan. takano@anesc.u-tokyo.ac.jp.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Takano
authors.affiliation: Key Laboratory of Saline-alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center (ASNESC), Northeast Forestry University, Harbin Hexing Road, Harbin 150040, China. shenkuiliu@nefu.edu.cn.
authors.forename: Shenkui
authors.initials: S
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D053263:Gene Regulatory Networks; D017343:Genes, Plant; D006861:Hydrogen Peroxide / Q000633:toxicity; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000633:toxicity; D008969:Molecular Sequence Data; D018384:Oxidative Stress / Q000235:genetics; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000502:physiology; D006109:Poaceae / Q000235:genetics*; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D055049:Salt Tolerance / Q000235:genetics*; D055051:Salt-Tolerant Plants / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D018076:DNA, Complementary; D018744:DNA, Plant; D019216:Metals, Heavy; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D012965:Sodium Chloride; D006861:Hydrogen Peroxide