title: Characterization of the Chloride Channel-Like, AtCLCg, Involved in Chloride Tolerance in Arabidopsis thaliana.
abstract: In plant cells, anion channels and transporters are essential for key functions such as nutrition, ion homeostasis and resistance to biotic or abiotic stresses. We characterized AtCLCg, a member of the chloride channel (CLC) family in Arabidopsis localized in the vacuolar membrane. When grown on NaCl or KCl, atclcg knock-out mutants showed a decrease in biomass. In the presence of NaCl, these mutants overaccumulate chloride in shoots. No difference in growth was detected in response to osmotic stress by mannitol. These results suggest a physiological function of AtCLCg in the chloride homeostasis during NaCl stress. AtCLCg shares a high degree of identity (62%) with AtCLCc, another vacuolar CLC essential for NaCl tolerance. However, the atclcc atclccg double mutant is not more sensitive to NaCl than single mutants. As the effects of both mutations are not additive, gene expression analyses were performed and revealed that: (i)AtCLCg is expressed in mesophyll cells, hydathodes and phloem while AtCLCc is expressed in stomata; and (ii)AtCLCg is repressed in the atclcc mutant background, and vice versa. Altogether these results demonstrate that both AtCLCc and AtCLCg are important for tolerance to excess chloride but not redundant, and form part of a regulatory network controlling chloride sensitivity.
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
authors.forename: Chi Tam
authors.initials: CT
authors.lastname: Nguyen
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
authors.forename: Astrid
authors.initials: A
authors.lastname: Agorio
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Jossier
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Depré
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Thomine
authors.affiliation: Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Université Paris-Sud, F-91198 Gif-sur-Yvette, France Université Paris 7 Denis Diderot, UFR Sciences du Vivant, 35 rue Hélène Brion, F-75205 Paris Cedex 13, France Sophie.Filleur@i2bc.paris-saclay.fr.
authors.forename: Sophie
authors.initials: S
authors.lastname: Filleur
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018118:Chloride Channels / Q000235:genetics / Q000378:metabolism*; D058503:Mesophyll Cells / Q000378:metabolism; D009997:Osmotic Pressure; D055049:Salt Tolerance / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; C556246:CLCc protein, Arabidopsis; C000613250:CLCg protein, Arabidopsis; D018118:Chloride Channels; D012965:Sodium Chloride
keywords: Arabidopsis thaliana; Chloride channel (CLC); NaCl stress; Vacuolar membrane