title: A special pair of phytohormones controls excitability, slow closure, and external stomach formation in the Venus flytrap.
abstract: Venus flytrap's leaves can catch an insect in a fraction of a second. Since the time of Charles Darwin, scientists have struggled to understand the sensory biology and biomechanics of this plant, Dionaea muscipula. Here we show that insect-capture of Dionaea traps is modulated by the phytohormone abscisic acid (ABA) and jasmonates. Water-stressed Dionaea, as well as those exposed to the drought-stress hormone ABA, are less sensitive to mechanical stimulation. In contrast, application of 12-oxo-phytodienoic acid (OPDA), a precursor of the phytohormone jasmonic acid (JA), the methyl ester of JA (Me-JA), and coronatine (COR), the molecular mimic of the isoleucine conjugate of JA (JA-Ile), triggers secretion of digestive enzymes without any preceding mechanical stimulus. Such secretion is accompanied by slow trap closure. Under physiological conditions, insect-capture is associated with Ca(2+) signaling and a rise in OPDA, Apparently, jasmonates bypass hapto-electric processes associated with trap closure. However, ABA does not affect OPDA-dependent gland activity. Therefore, signals for trap movement and secretion seem to involve separate pathways. Jasmonates are systemically active because application to a single trap induces secretion and slow closure not only in the given trap but also in all others. Furthermore, formerly touch-insensitive trap sectors are converted into mechanosensitive ones. These findings demonstrate that prey-catching Dionaea combines plant-specific signaling pathways, involving OPDA and ABA with a rapidly acting trigger, which uses ion channels, action potentials, and Ca(2+) signals.
authors: Institute for Molecular Plant Physiology and Biophysics, University Wuerzburg, D-97070 Wuerzburg, Germany.
authors: María
authors: M
authors: Escalante-Pérez
authors: Elzbieta
authors: E
authors: Krol
authors: Annette
authors: A
authors: Stange
authors: Dietmar
authors: D
authors: Geiger
authors: Khaled A S
authors: KA
authors: Al-Rasheid
authors: Bettina
authors: B
authors: Hause
authors: Erwin
authors: E
authors: Neher
authors: Rainer
authors: R
authors: Hedrich
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects; D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D003517:Cyclopentanes / Q000494:pharmacology; D031257:Droseraceae / Q000033:anatomy & histology* / Q000187:drug effects / Q000502:physiology*; D005231:Fatty Acids, Unsaturated / Q000096:biosynthesis; D007192:Indenes / Q000494:pharmacology; D007313:Insecta / Q000187:drug effects / Q000502:physiology; D054883:Oxylipins / Q000494:pharmacology; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology; D011235:Predatory Behavior / Q000187:drug effects; D013314:Stress, Mechanical; D013997:Time Factors
chemical_list: D000596:Amino Acids; D003517:Cyclopentanes; D005231:Fatty Acids, Unsaturated; D007192:Indenes; D054883:Oxylipins; D010937:Plant Growth Regulators; C058487:coronatine; C025999:12-oxophytodienoic acid; C011006:jasmonic acid; D000040:Abscisic Acid