ARP2/3 complex‐mediated actin dynamics is required for hydrogen peroxide‐induced stomatal closure in Arabidopsis

• Published in: Plant, cell and environment cell and environment, 2014-07, Vol.37 (7), p.1548-1560
• Main Authors: LI, XIN, LI, JIAN‐HUA, WANG, WEI, CHEN, NAI‐ZHI, MA, TONG‐SUO, XI, YA‐NAN, ZHANG, XIAO‐LU, LIN, HAI‐FEI, BAI, YANG, HUANG, SHAN‐JIN, CHEN, YU‐LING
• Format: Article
• Language: English
• Subjects: ABA; abscisic acid; Abscisic Acid - pharmacology; actin; Actin Cytoskeleton - drug effects; Actin Cytoskeleton - metabolism; Actin-Related Protein 2-3 Complex - metabolism; Actins - metabolism; Arabidopsis; Arabidopsis - drug effects; Arabidopsis - physiology; Arabidopsis Proteins - metabolism; ARPC4; ARPC5; Biological and medical sciences; Bridged Bicyclo Compounds, Heterocyclic - pharmacology; Depsipeptides - pharmacology; Fundamental and applied biological sciences. Psychology; guard cells; hydrogen; hydrogen peroxide; Hydrogen Peroxide - pharmacology; microfilaments; Models, Biological; Mutation - genetics; Plant Stomata - cytology; Plant Stomata - drug effects; Plant Stomata - physiology; Polymerization - drug effects; Protein Subunits - metabolism; stomatal movement; Thiazolidines - pharmacology
• ISSN: 0140-7791; 1365-3040
• DOI: 10.1111/pce.12259

Multiple cellular events like dynamic actin reorganization and hydrogen peroxide (H₂O₂) 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 H₂O₂ generation is indispensable for ABA induction of actin reorganization in guard cells of Arabidopsis that requires the presence of ARP2/3 complex. H₂O₂‐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 H₂O₂, suggesting that ARP2/3‐mediated actin nucleation is required for H₂O₂‐induced actin cytoskeleton remodelling. Furthermore, the expression of H₂O₂ biosynthetic related gene AtrbohD and the accumulation of H₂O₂ was delayed in response to ABA in arpc4 and arpc5, demonstrating that misregulated actin dynamics affects H₂O₂ production upon ABA treatment. These results support a possible causal relation between the production of H₂O₂ and actin dynamics in ABA‐mediated guard cell signalling: ABA triggers H₂O₂ 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 H₂O₂ production.