Actin filament dynamics are dominated by rapid growth and severing activity in the Arabidopsis cortical array
Open Access
- 26 January 2009
- journal article
- Published by Rockefeller University Press in The Journal of cell biology
- Vol. 184 (2), 269-280
- https://doi.org/10.1083/jcb.200806185
Abstract
Metazoan cells harness the power of actin dynamics to create cytoskeletal arrays that stimulate protrusions and drive intracellular organelle movements. In plant cells, the actin cytoskeleton is understood to participate in cell elongation; however, a detailed description and molecular mechanism(s) underpinning filament nucleation, growth, and turnover are lacking. Here, we use variable-angle epifluorescence microscopy (VAEM) to examine the organization and dynamics of the cortical cytoskeleton in growing and nongrowing epidermal cells. One population of filaments in the cortical array, which most likely represent single actin filaments, is randomly oriented and highly dynamic. These filaments grow at rates of 1.7 microm/s, but are generally short-lived. Instead of depolymerization at their ends, actin filaments are disassembled by severing activity. Remodeling of the cortical actin array also features filament buckling and straightening events. These observations indicate a mechanism inconsistent with treadmilling. Instead, cortical actin filament dynamics resemble the stochastic dynamics of an in vitro biomimetic system for actin assembly.Keywords
This publication has 59 references indexed in Scilit:
- Dynamics of Arabidopsis Dynamin-Related Protein 1C and a Clathrin Light Chain at the Plasma MembranePlant Cell, 2008
- Comparison of the Dynamics and Functional Redundancy of the Arabidopsis Dynamin-Related Isoforms DRP1A and DRP1C during Plant DevelopmentPlant Physiology, 2008
- Actin microfilament dynamics and actin side-binding proteins in plantsCurrent Opinion in Plant Biology, 2007
- Identification ofArabidopsisCyclase-associated Protein 1 as the First Nucleotide Exchange Factor for Plant ActinMolecular Biology of the Cell, 2007
- ACTIN BINDING PROTEIN29 fromLiliumPollen Plays an Important Role in Dynamic Actin RemodelingPlant Cell, 2007
- Actin-Filament Stochastic Dynamics Mediated by ADF/CofilinCurrent Biology, 2007
- Spatial and Temporal Relationships between Actin-Filament Nucleation, Capping, and DisassemblyCurrent Biology, 2007
- Mechanism of inhibition of cytoplasmic streaming by a myosin inhibitor, 2,3-butanedione monoximeProtoplasma, 2000
- Arp2/3 Complex and Actin Depolymerizing Factor/Cofilin in Dendritic Organization and Treadmilling of Actin Filament Array in LamellipodiaThe Journal of cell biology, 1999
- Rate constants for the reactions of ATP- and ADP-actin with the ends of actin filaments.The Journal of cell biology, 1986