ISSN:
1615-6102
Keywords:
Chitin fragments
;
Elicitor
;
Electron paramagnetic resonance
;
Hydroxyl radical
;
Reactive oxygen species
;
Rice suspension culture
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary N-acetylchitooligosaccharides, fragments of the backbone of fungal cell wall, trigger rapid membrane responses such as transient depolarization, and elicit defense reactions including phytoalexin production in suspension-cultured rice cells. The generation of reactive oxygen species triggered by the oligosaccharide signal was analyzed with EPR spectroscopy using a spin trapping system, 4-pyridyl 1-oxideN-tert-butyl nitrone (4-POBN) and ethanol. OH generation was detected as the α-hydroxyethyl adduct of 4-POBN after elicitation. Superoxide dismutase, catalase or diethylenetriamine pentaacetic acid, a metal chelator, inhibited $${}^ \cdot O$$ generation, proposing the following reaction sequence: generation of $${}^ \cdot O_{2^ - } $$ in response to the oligosaccharide elicitor, followed by dismutation to H2O2, then generation of $${}^ \cdot OH$$ by the reaction of H2O2 with Fe2+ that is generated by the reduction of Fe3+ by $${}^ \cdot O_{2^ - } $$ . Generation of the same reactive oxygen species was also triggered by calyculin A, a protein phosphatase inhibitor, alone, suggesting the involvement of protein phosphorylation in its regulation during the oligosaccharide signal transduction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01276805
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