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Jasmonates in plant stress responses and development
Claus Wasternack Halle/Saale, Germany May 2010 Leibniz Institute of Plant Biochemistry Past: Department of Natural Product Biotechnology, Presence: Molecular Signal Processing
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pollen maturation flower development
germination pollen maturation flower development fruit / seed development cell elongation leaf senescence root growth pathogens (virus, bacteria fungi) herbivores attraction of predators of parasitoides by release of volatiles osmotic stress/drought mycorrhiza pathogens (virus, bacteria fungi)
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d H2O JM Jasmonate-induced senescence in Hordeum vulgare
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Feussner and Wasternack, Ann Rev. Plant Biol. 2002
Localization of enzymes of jasmonate biosynthesis tomato barley barley Feussner and Wasternack, Ann Rev. Plant Biol. 2002
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4-CL-like CoA synthetases activate JA precursors in peroxisomes for ß-oxidation of the carboxylic acid side chain after Kienow et al., J. Exp. Bot. 59: (2008), Collab. E. Kombrink (-)-JA
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w-7-fatty acid desaturase
Mutants Gene product Phenotype JA biosynthesis dgl Galactolipase A1 Reduced JA level in leaves dad1 Phospholipase A1 Reduced filament elongation, male sterile, JA-deficient in flowers spr21 w-7-fatty acid desaturase Deficient in a-LeA and JA levels, no wound response dde2-2 AOS Male sterile, delayed anther development, opr3 OPR3 JA-deficient, reduced filament elongation, male sterile acx11 Acyl-CoA oxidase JA-deficient reduced wound response comatose COMATOSE/PXA1, ABC transporter Reduced JA content Zhai et al. 2007 Constitutive JA response cev1 constitutive expression of vegetative storage proteins hy1-101 Heme oxygenase HY1 Increased JA level, stunted growth, phytochrome chromophore deficiency joe2 ? Reduced inhibition of root growth, increased expression of LOX2 Others ore9, max2 F-box protein Delayed leaf senescence, more axillary branches Reduced sensitivity to JA coi1 F-box protein COI1/ JA receptor Reduced root growth inhibition, male sterile, reduced filament elongation, enhanced sensitivity to necrotrophic pathogens jai11 Tomato homologue of COI1 Female sterile, decreased wound-response jar1/jin4/jai2 JA amino acid conjugate synthase Reduced root growth inhibition by JA jin1/jai1 AtMYC2 (bHLHzip transcription factor) Reduced root growth inhibition axr1 RUB-activating enzyme jai4/sgt1b AtSGT1b Reduced root growth inhibition in the ein3 background 1tomato mutants
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Jasmonate biosynthesis in Arabidopsis
COOH 1 13-LOX AOS AOCs Arabidopsis a-linolenic acid 13-LOX 13-HPOT COOH HOO 13 AOS COOH O AOC3 AOC4 AOC1 AOC2 COOH O 12 cis-(+)-12-oxo-phytodienoic acid [OPDA] OPR3 b-oxidation COOH 3 7 O COOH O coi1 Gene expression (+)-7-iso-JA (-)-JA Leibniz Institute of Plant Biochemistry Department of Natural Product Biotechnology 7
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There is more than JA Wasternack, in
H. Hirt “Plant Stress Biology“, 2009
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Levels of 12-OH-JA, 12-HSO4-JA, JA and OPDA
differ dramatically pmole per g f.w. OPDA JA OH-JA HSO4-JA O-Glc-JA Z. mays dry seeds G. max immat. seeds , , ,753 V. faba pericarp , , ,937 C. pepo seeds n.d ,257 Z. mays d1 leaves , , n.d. S. esculentum cv. Lukullus leaves n.d.: not detectable; errors in the range of 2-10% Miersch et al., New Phytol., 177: (2008)
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JA signaling is switched off for a subset of genes by hydroxylation and sulfation
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Jasmonate biosynthesis in tomato
COOH 1 a-linolenic acid 13-LOX 13-HPOT COOH HOO 13 13-LOX anti-AOC AOS COOH O GUS-staining AOS AOC COOH O 12 Ovule-specific AOC expression, preferential accumulation of jasmonates in the pistil AOC cis-(+)-12-oxo-phytodienoic acid [OPDA] OPR3 Leaf cross section b-oxidation COOH 3 7 O COOH O Gene expression Is there any role of oxylipins in embryo development ? (+)-7-iso-JA (-)-JA jai1 11
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Which JA compound is the ligand of the JA receptor ?
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5, (2009) Collaboration between R. Solano´s group (Madrid), M. Hamberg (Stockholm) and the Halle group
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is most active in pulldown experiments yeast two hybrid interactions root growth assays - anthocyanin accumulation Epimerization as a mechanism activating a pre-existing pool of inactive JA compounds ?
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