title: Changes of Nitric Oxide and Its Relationship with H2O2 and Ca2+ in Defense Interactions between Wheat and Puccinia Triticina.
abstract: In this research, the wheat cultivar 'Lovrin 10' and Puccinia triticina races 165 and 260 were used to constitute compatible and incompatible combinations to investigate the relationship between NO and H2O2 and between NO and calcium (Ca(2+)) signaling in the cell defense process by pharmacological means. The specific fluorescent probe DAF-FM DA was coupled with confocal laser scanning microscopy and used to label intracellular nitric oxide (NO) and monitoring the real-time NO dynamics during the processes of wheat defense response triggered by P. triticina infection. The results showed that at 4 h after inoculation, weak green fluorescence was observed in the stomatal guard cells at the P. triticina infection site in the incompatible combination, which indicates a small amount of NO production. Twelve hours after inoculation, the fluorescence of NO in- cell adjacent to the stomata gradually intensified, and the NO fluorescent area also expanded continuously; the green fluorescence primarily occurred in the cells undergoing a hypersensitive response (HR) at 24-72 h after inoculation. For the compatible combination, however, a small amount of green fluorescence was observed in stomata where the pathogenic contact occurred at 4 h after inoculation, and fluorescence was not observed thereafter. Injections of the NO scavenger c-PTIO prior to inoculation postponed the onset of NO production to 48 h after inoculation and suppressed HR advancement. The injection of imidazole, a NADPH oxidase inhibitor, or EGTA, an extracellular calcium chelator, in the leaves prior to inoculation, delayed the onset of NO production in the incompatible combination and suppressed HR advancement. Combined with our previous results, it could be concluded that, Ca(2+) and hydrogen peroxide (H2O2) are involved in upstream of NO production to induce the HR cell death during P. triticina infection, and Ca(2+), NO and H2O2 are jointly involved in the signal transduction process of HR in the interaction system.
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Mei
authors.initials: M
authors.lastname: Qiao
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Sun
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Tianjie
authors.initials: T
authors.lastname: Sun
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Shengfang
authors.initials: S
authors.lastname: Han
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Hou
authors.affiliation: College of Life Science, Agricultural University of Hebei, Baoding, Hebei Province, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Wang
mesh_terms: D001487:Basidiomycota / Q000472:pathogenicity / Q000502:physiology*; D001565:Benzoates / Q000494:pharmacology; D002118:Calcium / Q000276:immunology* / Q000378:metabolism; D004533:Egtazic Acid / Q000494:pharmacology; D005452:Fluoresceins; D005456:Fluorescent Dyes; D016166:Free Radical Scavengers / Q000494:pharmacology; D054884:Host-Pathogen Interactions; D006861:Hydrogen Peroxide / Q000276:immunology* / Q000378:metabolism; D007093:Imidazoles / Q000494:pharmacology; D007267:Injections; D009569:Nitric Oxide / Q000276:immunology* / Q000378:metabolism; D010781:Photography; D010935:Plant Diseases / Q000276:immunology; D057865:Plant Immunity; D054046:Plant Stomata / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D015398:Signal Transduction; D013997:Time Factors; D014908:Triticum / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism
chemical_list: C503301:4-amino-5-methylamino-2',7'-difluorofluorescein diacetate; D001565:Benzoates; D005452:Fluoresceins; D005456:Fluorescent Dyes; D016166:Free Radical Scavengers; D007093:Imidazoles; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; D009569:Nitric Oxide; D004533:Egtazic Acid; C029899:imidazole; D006861:Hydrogen Peroxide; D002118:Calcium