title: ARP2/3 complex-mediated actin dynamics is required for hydrogen peroxide-induced stomatal closure in Arabidopsis.
abstract: Multiple cellular events like dynamic actin reorganization and hydrogen peroxide (H(2)O(2)) production were demonstrated to be involved in abscisic acid (ABA)-induced stomatal closure. However, the relationship between them as well as the underlying mechanisms remains poorly understood. Here, we showed that H(2)O(2) generation is indispensable for ABA induction of actin reorganization in guard cells of Arabidopsis that requires the presence of ARP2/3 complex. H(2)O(2) -induced stomatal closure was delayed in the mutants of arpc4 and arpc5, and the rate of actin reorganization was slowed down in arpc4 and arpc5 in response to H(2)O(2), suggesting that ARP2/3-mediated actin nucleation is required for H(2)O(2) -induced actin cytoskeleton remodelling. Furthermore, the expression of H(2)O(2) biosynthetic related gene AtrbohD and the accumulation of H(2)O(2) was delayed in response to ABA in arpc4 and arpc5, demonstrating that misregulated actin dynamics affects H(2)O(2) production upon ABA treatment. These results support a possible causal relation between the production of H(2)O(2) and actin dynamics in ABA-mediated guard cell signalling: ABA triggers H(2)O(2) generation that causes the reorganization of the actin cytoskeleton partially mediated by ARP2/3 complex, and ARP2/3 complex-mediated actin dynamics may feedback regulate H(2)O(2) production.
authors.affiliation: Hebei Key Laboratory of Molecular and Cellular Biology, College of Life Science, Hebei Normal University, Shijiazhuang, 050024, China; Key Laboratory of Plant Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Nai-Zhi
authors.initials: NZ
authors.lastname: Chen
authors.forename: Tong-Suo
authors.initials: TS
authors.lastname: Ma
authors.forename: Ya-Nan
authors.initials: YN
authors.lastname: Xi
authors.forename: Xiao-Lu
authors.initials: XL
authors.lastname: Zhang
authors.forename: Hai-Fei
authors.initials: HF
authors.lastname: Lin
authors.forename: Yang
authors.initials: Y
authors.lastname: Bai
authors.forename: Shan-Jin
authors.initials: SJ
authors.lastname: Huang
authors.forename: Yu-Ling
authors.initials: YL
authors.lastname: Chen
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism; D051376:Actin-Related Protein 2-3 Complex / Q000378:metabolism*; D000199:Actins / Q000378:metabolism*; D017360:Arabidopsis / Q000187:drug effects / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D047630:Depsipeptides / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D054046:Plant Stomata / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D058105:Polymerization / Q000187:drug effects; D021122:Protein Subunits / Q000378:metabolism; D053778:Thiazolidines / Q000494:pharmacology
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D000199:Actins; D029681:Arabidopsis Proteins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D047630:Depsipeptides; D021122:Protein Subunits; D053778:Thiazolidines; C057531:jasplakinolide; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; C037068:latrunculin B
keywords: ABA; ARPC4; ARPC5; guard cells