title: NADPH oxidase in plasma membrane is involved in stomatal closure induced by dehydroascorbate.
abstract: Stoma is surrounded by two guard cells, and regulates the contents of water and CO(2) in plant, its opening and closing was affected by various factors. Recently, dehydroascorbate was found to induce stomata closure and H(2)O(2) generation. However, the mechanism of H(2)O(2) production is not clear. DPI and imidazole inhibit the flavoprotein and the b(-type) cytochrome components of the NADPH oxidase complex. Application of DPI or imidazole with DHA together impaired stomatal closure and elevation of H(2)DCF-DA fluorescent intensity induced by DHA in guard cells. CoCl(2) and PD98059, as the blocker of calcium channel and the inhibitor of MAPKKK, both impaired stomatal closure induced by DHA. The results suggested that DHA-induced H(2)O(2) generation via activation of NADPH oxidase, and thus resulting in stomatal closure. Moreover, Ca(2+) channel and MAPK cascades were involved in stomatal closure induced by DHA.
authors.affiliation: National Key Laboratory of Tobacco Planting, Physiology and Biochemistry, 450002 Zhengzhou, China.
authors.forename: Yong Chun
authors.initials: YC
authors.lastname: Shi
authors.forename: Yun Peng
authors.initials: YP
authors.lastname: Fu
authors.forename: Wei Qun
authors.initials: WQ
authors.lastname: Liu
mesh_terms: D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism; D002374:Catalase / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology; D003035:Cobalt / Q000494:pharmacology; D003683:Dehydroascorbic Acid / Q000494:pharmacology*; D004229:Dithiothreitol / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000378:metabolism; D007093:Imidazoles / Q000494:pharmacology; D019255:NADPH Oxidases / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D010940:Plant Proteins / Q000378:metabolism; D054046:Plant Stomata / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D014026:Nicotiana / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology
chemical_list: D002121:Calcium Channel Blockers; D015220:Calcium Channels; D005419:Flavonoids; D007093:Imidazoles; D009861:Onium Compounds; D010940:Plant Proteins; D003035:Cobalt; C007517:diphenyleneiodonium; C029899:imidazole; D006861:Hydrogen Peroxide; D002374:Catalase; D019255:NADPH Oxidases; C018021:cobaltous chloride; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D004229:Dithiothreitol; D003683:Dehydroascorbic Acid