Control of actin assembly and disassembly at filament ends.

Department of Cell Biology, Washington University, Box 8228, St Louis, MO 631110, USA.
Current Opinion in Cell Biology (Impact Factor: 8.74). 03/2000; 12(1):97-103. DOI: 10.1016/S0955-0674(99)00062-9
Source: PubMed

ABSTRACT The most important discovery in the field is that the Arp2/3 complex nucleates assembly of actin filaments with free barbed ends. Arp2/3 also binds the sides of actin filaments to create a branched network. Arp2/3's nucleation activity is stimulated by WASP family proteins, some of which mediate signaling from small G-proteins. Listeria movement caused by actin polymerization can be reconstituted in vitro using purified proteins: Arp2/3 complex, capping protein, actin depolymerizing factor/cofilin, and actin. actin depolymerizing factor/cofilin increases the rate at which actin subunits leave pointed ends, and capping protein caps barbed ends.

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Available from: Dorothy A Schafer, Feb 05, 2014
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