title: Ethylene-induced stomatal closure in Arabidopsis occurs via AtrbohF-mediated hydrogen peroxide synthesis.
abstract: Ethylene is a plant hormone that regulates many aspects of growth and development. Despite the well-known association between ethylene and stress signalling, its effects on stomatal movements are largely unexplored. Here, genetic and physiological data are provided that position ethylene into the Arabidopsis guard cell signalling network, and demonstrate a functional link between ethylene and hydrogen peroxide (H(2)O(2)). In wild-type leaves, ethylene induces stomatal closure that is dependent on H(2)O(2) production in guard cells, generated by the nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase AtrbohF. Ethylene-induced closure is inhibited by the ethylene antagonists 1-MCP and silver. The ethylene receptor mutants etr1-1 and etr1-3 are insensitive to ethylene in terms of stomatal closure and H(2)O(2) production. Stomata of the ethylene signalling ein2-1 and arr2 mutants do not close in response to either ethylene or H(2)O(2) but do generate H(2)O(2) following ethylene challenge. Thus, the data indicate that ethylene and H(2)O(2) signalling in guard cells are mediated by ETR1 via EIN2 and ARR2-dependent pathway(s), and identify AtrbohF as a key mediator of stomatal responses to ethylene.
authors.affiliation: Centre for Research in Plant Science, Genomics Research Institute, Faculty of Applied Sciences, University of the West of England, Bristol, Coldharbour Lane, Bristol BS16 1QY, UK.
authors.forename: Radhika
authors.initials: R
authors.lastname: Desikan
authors.forename: Kathryn
authors.initials: K
authors.lastname: Last
authors.forename: Rhian
authors.initials: R
authors.lastname: Harrett-Williams
authors.forename: Cecilia
authors.initials: C
authors.lastname: Tagliavia
authors.forename: Klaus
authors.initials: K
authors.lastname: Harter
authors.forename: Richard
authors.initials: R
authors.lastname: Hooley
authors.forename: John T
authors.initials: JT
authors.lastname: Hancock
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Neill
mesh_terms: D017360:Arabidopsis / Q000378:metabolism / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D003300:Copper / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D015398:Signal Transduction; D012834:Silver / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D005030:Ethylenes; D012834:Silver; D003300:Copper; C036216:ethylene; D006861:Hydrogen Peroxide