The Dinor Isoprostane Pathway in Plants
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Isoprostanes are products of free radical-catalyzed oxidation of arachidonic acid (20:4) in mammals , However, isoprostanoids can be formed virtually from any natural polyunsaturated fatty acid that contains at least three double bonds. a-Linolenic acid (18:3) fulfills that criterion, and thus, can be oxidized to a variety of C-18 isoprostane classes (dinor isoprostanes) . Dinor isoprostanes in animals are either derived from β- oxidation of C20 isoprostanes or peroxidation of γ-linolenic acid (18:3) but not from α-linolenic acid which is only a trace fatty acid in mammals [3,4]. In contrast, higher plants generally are devoid of arachidonate and biosynthesize α-linolenate as one of the major polyunsaturated fatty acids. Since α-linolenate derived dinor isoprostanes differ in structure from mammalian dinor isoprostanes, plant dinor isoprostanes have been termed phytoprostanes .
KeywordsJasmonic Acid Butyl Hydroperoxide Physiol Regulatory Integrative Comp Tobacco Cell Suspension Culture Trace Fatty Acid
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- 3.Hou X, Roberts II LJ, Taber DF, Morrow JD, Kanai K, Gobeil JR, F Beauchamp MH, Bemier SG, Lepage G, Varma DR, Chemtob S. 2,3-Dinor-5,6-dihydro-15-F2t-isoprostane: a bioactive prostanoid metabolite. Am J Physiol Regulatory Integrative Comp Physiol 2001; 281:R391–R400.Google Scholar
- 5.Imbusch R, Mueller MJ. Formation of isoprostane F2-like compounds (phytoprostanes F) from a-linolenic acid in plants. Free Rad Biol Med 2000; 28:720–726.Google Scholar
- 7.Thoma I, Loeffler L, Sinha AK, Gupta M, Krischke M, Steffan B, Roitsch T, Mueller MJ. Cyclopentenone isoprostanes induced by reactive oxygen species trigger defense gene activation and phytoalexin accumulation in plants. Plant J, 2003, acceptedGoogle Scholar
- 8.Krischke M, Loeffler C, Mueller MJ. Biosynthesis of 14,15-dehydro-12-oxo-phytodienoic acid and related cyclopentenones via the phytoprostane D1 pathway. Phytochemistry 2003; in press.Google Scholar