title: Deciphering early events involved in hyperosmotic stress-induced programmed cell death in tobacco BY-2 cells.
abstract: Hyperosmotic stresses represent one of the major constraints that adversely affect plants growth, development, and productivity. In this study, the focus was on early responses to hyperosmotic stress- (NaCl and sorbitol) induced reactive oxygen species (ROS) generation, cytosolic Ca(2+) concentration ([Ca(2+)]cyt) increase, ion fluxes, and mitochondrial potential variations, and on their links in pathways leading to programmed cell death (PCD). By using BY-2 tobacco cells, it was shown that both NaCl- and sorbitol-induced PCD seemed to be dependent on superoxide anion (O2·(-)) generation by NADPH-oxidase. In the case of NaCl, an early influx of sodium through non-selective cation channels participates in the development of PCD through mitochondrial dysfunction and NADPH-oxidase-dependent O2·(-) generation. This supports the hypothesis of different pathways in NaCl- and sorbitol-induced cell death. Surprisingly, other shared early responses, such as [Ca(2+)]cyt increase and singlet oxygen production, do not seem to be involved in PCD.
authors.affiliation: Université Paris Diderot, Sorbonne Paris Cité, Institut des Energies de Demain (UMR8236), Paris, France.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Monetti
authors.forename: Takashi
authors.initials: T
authors.lastname: Kadono
authors.forename: Daniel
authors.initials: D
authors.lastname: Tran
authors.forename: Elisa
authors.initials: E
authors.lastname: Azzarello
authors.forename: Delphine
authors.initials: D
authors.lastname: Arbelet-Bonnin
authors.forename: Bernadette
authors.initials: B
authors.lastname: Biligui
authors.forename: Joël
authors.initials: J
authors.lastname: Briand
authors.forename: Tomonori
authors.initials: T
authors.lastname: Kawano
authors.forename: Stefano
authors.initials: S
authors.lastname: Mancuso
authors.forename: François
authors.initials: F
authors.lastname: Bouteau
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D008928:Mitochondria / Q000378:metabolism; D019255:NADPH Oxidases / Q000378:metabolism; D009997:Osmotic Pressure; D026082:Singlet Oxygen / Q000378:metabolism* / Q000494:pharmacology; D012965:Sodium Chloride / Q000494:pharmacology; D013012:Sorbitol / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D014026:Nicotiana / Q000187:drug effects / Q000502:physiology*
chemical_list: D013481:Superoxides; D026082:Singlet Oxygen; D012965:Sodium Chloride; D013012:Sorbitol; D019255:NADPH Oxidases; D002118:Calcium
keywords: Calcium; NaCl; Nicotiana tabacum; hyperosmotic stress; mitochondria; non-selective cation channels; programmed cell death; reactive oxygen species.