title: 12-hydroxyjasmonic acid glucoside is a COI1-JAZ-independent activator of leaf-closing movement in Samanea saman.
abstract: Jasmonates are ubiquitously occurring plant growth regulators with high structural diversity that mediate numerous developmental processes and stress responses. We have recently identified 12-O-β-D-glucopyranosyljasmonic acid as the bioactive metabolite, leaf-closing factor (LCF), which induced nyctinastic leaf closure of Samanea saman. We demonstrate that leaf closure of isolated Samanea pinnae is induced upon stereospecific recognition of (-)-LCF, but not by its enantiomer, (+)-ent-LCF, and that the nonglucosylated derivative, (-)-12-hydroxyjasmonic acid also displays weak activity. Similarly, rapid and cell type-specific shrinkage of extensor motor cell protoplasts was selectively initiated upon treatment with (-)-LCF, whereas flexor motor cell protoplasts did not respond. In these bioassays related to leaf movement, all other jasmonates tested were inactive, including jasmonic acid (JA) and the potent derivates JA-isoleucine and coronatine. By contrast, (-)-LCF and (-)-12-hydroxyjasmonic acid were completely inactive with respect to activation of typical JA responses, such as induction of JA-responsive genes LOX2 and OPCL1 in Arabidopsis (Arabidopsis thaliana) or accumulation of plant volatile organic compounds in S. saman and lima bean (Phaseolus lunatus), generally considered to be mediated by JA-isoleucine in a COI1-dependent fashion. Furthermore, application of selective inhibitors indicated that leaf movement in S. saman is mediated by rapid potassium fluxes initiated by opening of potassium-permeable channels. Collectively, our data point to the existence of at least two separate JA signaling pathways in S. saman and that 12-O-β-D-glucopyranosyljasmonic acid exerts its leaf-closing activity through a mechanism independent of the COI1-JAZ module.
authors.affiliation: Department of Chemistry, Tohoku University, Sendai 980-8578, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Axel
authors.initials: A
authors.lastname: Mithöfer
authors.forename: Erich
authors.initials: E
authors.lastname: Kombrink
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Boland
authors.forename: Shin
authors.initials: S
authors.lastname: Hamamoto
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Uozumi
authors.forename: Kentaro
authors.initials: K
authors.lastname: Tohma
authors.forename: Minoru
authors.initials: M
authors.lastname: Ueda
mesh_terms: D003517:Cyclopentanes / Q000737:chemistry / Q000494:pharmacology*; D007887:Fabaceae / Q000166:cytology / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D005960:Glucosides / Q000737:chemistry / Q000494:pharmacology*; D049990:Membrane Transport Modulators / Q000494:pharmacology; D009068:Movement / Q000187:drug effects; D054883:Oxylipins / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011523:Protoplasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D055549:Volatile Organic Compounds / Q000032:analysis
chemical_list: D003517:Cyclopentanes; D005960:Glucosides; D049990:Membrane Transport Modulators; D054883:Oxylipins; D010940:Plant Proteins; D055549:Volatile Organic Compounds; C011006:jasmonic acid