title: Arabidopsis Qc-SNARE gene AtSFT12 is involved in salt and osmotic stress responses and Na(+) accumulation in vacuoles.
abstract: AtSFT12, an Arabidopsis Qc-SNARE protein, is localized to Golgi organelles and is involved in salt and osmotic stress responses via accumulation of Na (+) in vacuoles. To reduce the detrimental effects of environmental stresses, plants have evolved many defense mechanisms. Here, we identified an Arabidopsis Qc-SNARE gene, AtSFT12, involved in salt and osmotic stress responses using an activation-tagging method. Both activation-tagged plants and overexpressing transgenic plants (OXs) of the AtSFT12 gene were tolerant to high concentrations of NaCl, LiCl, and mannitol, whereas loss-of-function mutants were sensitive to NaCl, LiCl, and mannitol. AtSFT12 transcription increased under NaCl, ABA, cold, and mannitol stresses but not MV treatment. GFP-fusion AtSFT12 protein was juxtaposed with Golgi marker, implying that its function is associated with Golgi-mediated transport. Quantitative measurement of Na(+) using induced coupled plasma atomic emission spectroscopy revealed that AtSFT12 OXs accumulated significantly more Na(+) than WT plants. In addition, Na(+)-dependent fluorescence analysis of Sodium Green showed comparatively higher Na(+) accumulation in vacuoles of AtSFT12 OX cells than in those of WT plant cells after salt treatments. Taken together, our findings suggest that AtSTF12, a Golgi Qc-SNARE protein, plays an important role in salt and osmotic stress responses and functions in the salt stress response via sequestration of Na(+) in vacuoles.
authors.affiliation: Department of Molecular Biology, Pusan National University, Busan, 609-735, Korea.
authors.forename: Vaishali N
authors.initials: VN
authors.lastname: Tarte
authors.forename: Hye-Yeon
authors.initials: HY
authors.lastname: Seok
authors.forename: Dong-Hyuk
authors.initials: DH
authors.lastname: Woo
authors.forename: Dinh Huan
authors.initials: DH
authors.lastname: Le
authors.forename: Huong T
authors.initials: HT
authors.lastname: Tran
authors.forename: Ji-Won
authors.initials: JW
authors.lastname: Baik
authors.forename: In Soon
authors.initials: IS
authors.lastname: Kang
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Taijoon
authors.initials: T
authors.lastname: Chung
authors.forename: Yong-Hwan
authors.initials: YH
authors.lastname: Moon
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D006056:Golgi Apparatus / Q000187:drug effects / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D009995:Osmosis / Q000187:drug effects*; D030821:Plants, Genetically Modified; D021381:Protein Transport / Q000187:drug effects; D050767:Qc-SNARE Proteins / Q000235:genetics* / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics*; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic / Q000187:drug effects; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D050767:Qc-SNARE Proteins; C000605704:SFT12 protein, Arabidopsis; D012965:Sodium Chloride; D012964:Sodium