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Review
. 2013 Apr 17;587(8):1215-9.
doi: 10.1016/j.febslet.2013.01.062. Epub 2013 Feb 5.

Biophysics of actin filament severing by cofilin

W Austin Elam  1 , Hyeran Kang, Enrique M De la Cruz
Affiliations
Review

Biophysics of actin filament severing by cofilin

W Austin Elam et al. FEBS Lett. .

Abstract

The continuous assembly and disassembly of actin filament networks is vital for cellular processes including division, growth, and motility. Network remodeling is facilitated by cofilins, a family of essential regulatory proteins that fragment actin filaments. Cofilin induces net structural changes in filaments that render them more compliant in bending and twisting. A model in which local stress accumulation at mechanical discontinuities, such as boundaries of bare and cofilin-decorated filament segments, accounts for the cofilin concentration dependence of severing, including maximal activity at sub-stoichiometric binding densities. Real-time imaging of cofilin-mediated filament severing supports the boundary-fracture model. The severing model predicts that fragmentation is promoted by factors modulating filament mechanics (e.g. tethering, cross-linking, or deformation), possibly explaining enhanced in vivo severing activities.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
One-dimensional Ising lattice model with nearest-neighbor cooperative interactions.
Figure 2
Figure 2
(A) Actin filament conformational fluctuations span broad timescales. Filaments display large-scale tumbling, bending, and twisting motions. Individual actin subunits undergo sub-microsecond timescale dynamics that modulate subunit interfaces. (B) Cofilin binding introduces mechanical discontinuity that promotes filament severing.
See this image and copyright information in PMC

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References

    1. Pollard T, Borisy G. Cellular motility driven by assembly and disassembly of actin filaments. Cell. 2003;112:453–465. - PubMed
    1. Fass J, Gehler S, Sarmiere P, Letourneau P, Bamburg J. Regulating filopodial dynamics through actin-depolymerizing factor/cofilin. Anatomical Science International. 2004;79:173–183. - PubMed
    1. Oosawa F, Asakura S. Thermodynamics of the polymerization of protein. Academic Press; 1975.
    1. Howard J. Mechanics of motor proteins and the cytoskeleton. Sunderland, MA: Sinauer Associates; 2001.
    1. De La Cruz E, Roland J, McCullough B, Blanchoin L, Martiel J. Origin of twist-bend coupling in actin filaments. Biophysical Journal. 2010;99:1852–1860. - PMC - PubMed

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