title: Interaction of nitric oxide and reactive oxygen species and associated regulation of root growth in wheat seedlings under zinc stress.
abstract: The inhibition of root growth was investigated in wheat seedlings exposed to 3mM zinc (Zn). Zn treatment with or without 250 µM 2-phenyl-4,4,5,5,-tetrame-thylimidazoline-3-oxide-1-oxyl (PTIO) or 10 µM diphenylene iodonium (DPI) significantly inhibited growth, increased malondialdehyde content and lowered cell viability in roots. The most prominent changes of these three parameters at Zn+DPI treatment could be partly blocked by high PTIO concentration (1mM). The production of nitric oxide (NO) and hydrogen peroxide (H2O2) influenced each other under different treatments, with the highest NO level and the highest H2O2 accumulation in Zn+DPI-treated roots. Compared with Zn-stressed roots, catalase, soluble peroxidase (POD), ascorbate peroxidase and superoxide dismutase decreased in Zn+DPI-treated roots, suggesting that ROS generation from plasma membrane (PM) NADPH oxidase was associated with the regulation of antioxidant enzyme activities. Additionally, Zn-treated roots exhibited significant decreases in cell wall-bound POD, diamine oxidase and polyamine oxidase activities. Our results suggested that Zn-induced effects on root growth resulted from NO interaction with H2O2 and that Zn+DPI-induced strongest inhibition could be explained by the highest increase in the endogenous NO content and the reduction of extracellular ROS production.
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Duan
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Xiaoning
authors.initials: X
authors.lastname: Li
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Ding
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhao
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Aifeng
authors.initials: A
authors.lastname: Guo
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yao
authors.affiliation: School of Life Science, Northwest Normal University, Lanzhou 730070, PR China. Electronic address: xbsfyangyingli@163.com.
authors.forename: Yingli
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D003497:Cyclic N-Oxides / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000378:metabolism; D007093:Imidazoles / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D009569:Nitric Oxide / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D018517:Plant Roots / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D013312:Stress, Physiological; D014908:Triticum / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D015032:Zinc / Q000378:metabolism / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D003497:Cyclic N-Oxides; D004791:Enzyme Inhibitors; D016166:Free Radical Scavengers; D007093:Imidazoles; D009861:Onium Compounds; D017382:Reactive Oxygen Species; C079391:2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide; D009569:Nitric Oxide; C007517:diphenyleneiodonium; D006861:Hydrogen Peroxide; D015032:Zinc
keywords: Hydrogen peroxide; Nitric oxide; Root growth; Wheat; Zinc