Free Fatty Acids and Methyl Jasmonate Trigger Defense Reactions in Laminaria digitata.
Arachidonic acid, linolenic acid and methyl jasmonate (MeJA) were found to be strong triggers of an oxidative burst in the kelp Laminaria digitata. These findings constitute the first report of an oxidative burst in an algal system induced by free fatty acids. The source of reactive oxygen species can be at least partially inhibited by diphenylene iodonium (DPI). Treatment with arachidonic acid increases the levels of a number of free fatty acids [including myristic (C14:0), linoleic (C18:2), linolenic (C18:3) and eicosapentaeneoic (C20:5) acids] and hydroxylated derivatives [such as 15-hydroxyeicosatetraenoic acid (15-HETE), 13-hydroxyoctadecatrienoic acid (13-HOTE) and 15-hydroxyeicosapentaenoic acid (15-HEPE)]. Similar to a previous report of the function of an alginate oligosaccharide-triggered oxidative burst in the establishment of resistance in L. digitata against infection by its brown algal endophyte Laminariocolax tomentosoides, C20:4- and MeJA-induced oxidative bursts seem to be involved in establishing the same protection in L. digitata. Altogether, this study supports the notion that lipid oxidation signaling plays a key role in defense induction in marine brown algae.
Küpper
Frithjof C
FC
Scottish Association for Marine Science, Dunstaffnage Marine Laboratory, Oban, Argyll PA37 1QA, Scotland, UK. fck@sams.ac.uk
Gaquerel
Emmanuel
E
Cosse
Audrey
A
Adas
Fadi
F
Peters
Akira F
AF
Müller
Dieter G
DG
Kloareg
Bernard
B
Salaün
Jean-Pierre
JP
Potin
Philippe
P
D000085:Acetates / Q000494:pharmacology*; D016718:Arachidonic Acid / Q000494:pharmacology; D003517:Cyclopentanes / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D007795:Laminaria / Q000187:drug effects / Q000378:metabolism*; D009861:Onium Compounds / Q000494:pharmacology; D054883:Oxylipins / Q000378:metabolism / Q000494:pharmacology*; D016897:Respiratory Burst; D017962:alpha-Linolenic Acid / Q000494:pharmacology
D000085:Acetates; D003517:Cyclopentanes; D005230:Fatty Acids, Nonesterified; D009861:Onium Compounds; D054883:Oxylipins; D017962:alpha-Linolenic Acid; D016718:Arachidonic Acid; C007517:diphenyleneiodonium; C072239:methyl jasmonate; D006861:Hydrogen Peroxide