12-oxophytodienoic-acid and methyl-jasmonate

13-lipoxygenases (13-LOX) catalyze the dioxygenation of various polyunsaturated fatty acids (PUFAs), of which α-linolenic acid (LeA) is converted to 13-S-hydroperoxyoctadeca-9, 11, 15-trienoic acid (13-HPOT), the precursor for the prostaglandin-like plant hormones cis-(+)-12-oxophytodienoic acid (12-OPDA) and methyl jasmonate (MJ). This study aimed for characterizing the four annotated

Topics: Acetates; Amino Acid Sequence; Arabidopsis; Arabidopsis Proteins; Cyclopentanes; Fatty Acids, Unsaturated; Gene Expression Regulation, Plant; Linoleic Acids; Lipoxygenase; Oxylipins

The corn leaf aphid (CLA;

Topics: Acetates; Animals; Aphids; Benzoxazines; Cyclopentanes; Ethylenes; Fatty Acids, Unsaturated; Fertility; Glucans; Herbivory; Oxylipins; Phloem; Zea mays

In plants, cis-jasmone (CJ) is synthesized from α-linolenic acid (LA) via two biosynthetic pathways using jasmonic acid (JA) and iso-12-oxo-phytodienoic acid (iso-OPDA) as key intermediates. However, there have been no reports documenting CJ production by microorganisms. In the present study, the production of fungal-derived CJ by Lasiodiplodia theobromae was observed for the first time, although this production was not observed for Botrytis cinerea, Verticillium longisporum, Fusarium oxysporum, Gibberella fujikuroi, and Cochliobolus heterostrophus. To investigate the biosynthetic pathway of CJ in L. theobromae, administration experiments using [18,18,18-

Topics: Acetates; Ascomycota; Biosynthetic Pathways; Cyclopentanes; Deuterium; Fatty Acids, Unsaturated; Metabolome; Oxylipins

Methyl jasmonate (MeJA) was tested by seed treatment for its ability to protect tomato seedlings against fusarium wilt caused by the soil-borne fungal pathogen Fusarium oxysporum f.sp. lycopersici. Isolated from Solanum lycopersicon L. seeds, cv. Beta fungus was identified as F. oxysporum f.sp. lycopersici Race 3 fungus by using phytopathological and molecular methods. MeJA applied at 0.01, 0.1 and 1 mM reduced spore germination and mycelial growth in vitro. Soaking of tomato seeds in MeJA solution at 0.1 mM for 1 h significantly enhanced the resistance level against the tested fungus in tomato seedlings 4 weeks after inoculation. The extracts from leaves of 15-day-old seedlings obtained from previously MeJA soaked seeds had the ability to inhibit in vitro spore germination of tested fungus. In these seedlings a significant increase in the levels phenolic compounds such as salicylic acid (SA), kaempferol and quercetin was observed. Up-regulation of phenylalanine ammonia-lyase (PAL5) and benzoic acid/salicylic acid carboxyl methyltransferase (BSMT) genes and down-regulation of the isochorysmate synthase (ICS) gene in response to exogenous MeJA application indicate that the phenylalanine ammonia-lyase (PAL), not the isochorismate (IC) pathway, is the primary route for SA production in tomato. Moreover, the increased accumulation of the flavonols quercetin and kaempferol appears closely related to the increase of PAL5, chalcone synthase (CHS) and flavonol synthase/flavanone 3-hydroxylase-like (FLS) genes. Elevated levels of salicylic acid in seedlings raised from MeJA-soaked seeds were simultaneously accompanied by a decrease of jasmonic acid, the precursor of MeJA, and an increase of 12-oxo-phytodienoic acid (OPDA), the precursor of jasmonic acid. The present results indicate that the priming of tomato seeds with 0.1mM MeJA before sowing enables the seedlings grown from these seeds to reduce the attack of the soil-borne fungal pathogen F. oxysporum f.sp. lycopersici, so it can be applied in practice.

Topics: Acetates; Biosynthetic Pathways; Cyclopentanes; Disease Resistance; Fatty Acids, Unsaturated; Flavonols; Fusarium; Gene Expression Regulation, Plant; Genes, Plant; Oxylipins; Phenols; Plant Diseases; Plant Extracts; Plant Leaves; Salicylic Acid; Seedlings; Seeds; Solanum lycopersicum; Spores, Fungal

Linoleic acid metabolites, (-)-methyl jasmonate and (+)-12-oxophytodienoic acid ((+)-12-oxo-PDA), were prepared from the same precursor (1,2-trans, 1,3-cis, 2'Z)-2-(pent-2'-enyl)-cyclopent-4-en-1,3-diol, which was obtained by regioselective pent-2-enylation of cyclopentadiene and following photooxidation to cis-1,3-diol. A methoxycarbonylmethyl substituent was introduced to the cyclopentane ring via alkylation of the pi-allyl palladium intermediate derived from (1R,2S,3S,2'Z)-3-acetoxy-2-(pent-2'-enyl)cyclopent-4-ene-1-ol with dimethyl malonate for (-)-methyl jasmonate. The alpha-chain was introduced to the cyclopentane ring via the S(N)2 type nucleophilic substitution of (1S,2R,3R,2'Z)-3-acetoxy-2-(pent-2'-enyl)cyclopent-4-ene-1-ol with a dialkylcuprate for (+)-12-oxo-PDA.

Topics: Acetates; Cyclopentanes; Fatty Acids, Unsaturated; Oxylipins

Conifers produce terpenoid-based oleoresins as constitutive and inducible defenses against herbivores and pathogens. Much information is available about the genes and enzymes of the late steps of oleoresin terpenoid biosynthesis in conifers, but almost nothing is known about the early steps which proceed via the methylerythritol phosphate (MEP) pathway. Here we report the cDNA cloning and functional identification of three Norway spruce (Picea abies) genes encoding 1-deoxy-D-xylulose 5-phosphate synthase (DXS), which catalyzes the first step of the MEP pathway, and their differential expression in the stems of young saplings. Among them are representatives of both types of plant DXS genes. A single type I DXS gene is constitutively expressed in bark tissue and not affected by wounding or fungal application. In contrast, two distinct type II DXS genes, PaDXS2A and PaDXS2B, showed increased transcript abundance after these treatments as did two other genes of the MEP pathway tested, 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) and 4-hydroxyl 3-methylbutenyl diphosphate reductase (HDR). We also measured gene expression in a Norway spruce cell suspension culture system that, like intact trees, accumulates monoterpenes after treatment with methyl jasmonate. These cell cultures were characterized by an up-regulation of monoterpene synthase gene transcripts and enzyme activity after elicitor treatment, as well as induced formation of octadecanoids, including jasmonic acid and 12-oxophytodienoic acid. Among the Type II DXS genes in cell cultures, PaDXS2A was induced by treatment with chitosan, methyl salicylate, and Ceratocystis polonica (a bark beetle-associated, blue-staining fungal pathogen of Norway spruce). However, PaDXS2B was induced by treatment with methyl jasmonate and chitosan, but was not affected by methyl salicylate or C. polonica. Our results suggest distinct functions of the three DXS genes in primary and defensive terpenoid metabolism in Norway spruce.

Topics: Acetates; Amino Acid Sequence; Cells, Cultured; Cloning, Molecular; Cyclopentanes; Fatty Acids, Unsaturated; Gene Expression Regulation, Plant; Gene Library; Intramolecular Lyases; Molecular Sequence Data; Oxylipins; Picea; Resins, Plant; Sequence Homology, Amino Acid; Terpenes; Transcription, Genetic; Transferases

Oxylipins of the jasmonate pathway and synthetic functional analogs have been analyzed for their elicitor-like activities in an assay based on the induced accumulation of glyceollins, the phytoalexins of soybean (Glycine max L.), in cell suspension cultures of this plant. Jasmonic acid (JA) and its methyl ester showed weak phytoalexin-inducing activity when compared to an early jasmonate biosynthetic precursor, 12-oxo-phytodienoic acid (OPDA), as well as to the bacterial phytotoxin coronatine and certain 6-substituted indanoyl-L-isoleucine methyl esters, which all were highly active. Interestingly, different octadecanoids and indanoyl conjugates induced the accumulation of transcripts of various defense-related genes to different degrees, indicating distinct induction competencies. Therefore, these signaling compounds and mimics were further analyzed for their effects on signal transduction elements, such as the transient enhancement of the cytosolic Ca2+ concentration and MAP kinase activation, which are known to be initiated by a soybean pathogen-derived beta-glucan elicitor. In contrast to the beta-glucan elicitor, none of the other compounds tested triggered these early signaling elements. Moreover, endogenous levels of OPDA and JA in soybean cells were shown to be unaffected after treatment with beta-glucans. Thus, OPDA and JA, which are functionally mimicked by coronatine and a variety of 6-substituted derivatives of indanoyl-L-isoleucine methyl ester, represent highly efficient signaling compounds of a lipid-based pathway not deployed in the beta-glucan elicitor-initiated signal transduction.

Topics: Acetates; Amino Acids; Benzopyrans; Cyclopentanes; Fatty Acids, Unsaturated; Gene Expression Regulation, Plant; Glycine max; Indenes; Mitogen-Activated Protein Kinases; Molecular Mimicry; Oxylipins; Plant Growth Regulators; Pterocarpans; RNA, Messenger; Signal Transduction

Coronatine-inducible tyrosine aminotransferase (TAT), which catalyses the transamination from tyrosine to p-hydroxyphenylpyruvate, is the first enzyme of a pathway leading via homogentisic acid to plastoquinone and tocopherols, the latter of which are known to be radical scavengers in plants. TAT can be also induced by the octadecanoids methyl jasmonate (MeJA) and methyl-12-oxophytodienoic acid (MeOPDA), as well as by wounding, high light, UV light and the herbicide oxyfluorfen. In order to elucidate the role of octadecanoids in the process of TAT induction in Arabidopsis thaliana (L.) Heynh., the jasmonate-deficient mutant delayed dehiscence (dde1) was used, in which the gene for 12-oxophytodienoic acid reductase 3 is disrupted. The amount of immunodetectable TAT was low. The enzyme was still fully induced by coronatine as well as by MeJA although induction by the latter was to a lesser extent and later than in the wild type. Treatment with MeOPDA, wounding and UV light, however, had hardly any effects. Tocopherol levels that showed considerable increases in the wild type after some treatments were much less affected in the mutant. However, starting levels of tocopherol were higher in non-induced dde1 than in the wild type. We conclude that jasmonate plays an important role in the signal transduction pathway regulating TAT activity and the biosynthesis of its product tocopherol.

Topics: Acetates; Arabidopsis; Cyclopentanes; Enzyme Induction; Fatty Acids, Unsaturated; Halogenated Diphenyl Ethers; Herbicides; Light; Mutation; Oxylipins; Phenyl Ethers; Phenylpyruvic Acids; Stress, Mechanical; Tocopherols; Tyrosine; Tyrosine Transaminase; Ultraviolet Rays