[HTML][HTML] Cellular motility driven by assembly and disassembly of actin filaments

TD Pollard, GG Borisy - Cell, 2003 - cell.com
Cell, 2003cell.com
Motile cells extend a leading edge by assembling a branched network of actin filaments that
produces physical force as the polymers grow beneath the plasma membrane. A core set of
proteins including actin, Arp2/3 complex, profilin, capping protein, and ADF/cofilin can
reconstitute the process in vitro, and mathematical models of the constituent reactions
predict the rate of motion. Signaling pathways converging on WASp/Scar proteins regulate
the activity of Arp2/3 complex, which mediates the initiation of new filaments as branches on …
Abstract
Motile cells extend a leading edge by assembling a branched network of actin filaments that produces physical force as the polymers grow beneath the plasma membrane. A core set of proteins including actin, Arp2/3 complex, profilin, capping protein, and ADF/cofilin can reconstitute the process in vitro, and mathematical models of the constituent reactions predict the rate of motion. Signaling pathways converging on WASp/Scar proteins regulate the activity of Arp2/3 complex, which mediates the initiation of new filaments as branches on preexisting filaments. After a brief spurt of growth, capping protein terminates the elongation of the filaments. After filaments have aged by hydrolysis of their bound ATP and dissociation of the γ phosphate, ADF/cofilin proteins promote debranching and depolymerization. Profilin catalyzes the exchange of ADP for ATP, refilling the pool of ATP-actin monomers bound to profilin, ready for elongation.
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