Interaction of human Arp2/3 complex and the Listeria monocytogenes ActA protein in actin filament nucleation
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Updated: Aug 3, 2026

Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
M D Welch1, J Rosenblatt, J Skoble
1Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94143, USA.
Abstract:
Actin filament assembly at the cell surface of the pathogenic bacterium Listeria monocytogenes requires the bacterial ActA surface protein and the host cell Arp2/3 complex. Purified Arp2/3 complex accelerated the nucleation of actin polymerization in vitro, but pure ActA had no effect. However, when combined, the Arp2/3 complex and ActA synergistically stimulated the nucleation of actin filaments. This mechanism of activating the host Arp2/3 complex at the L. monocytogenes surface may be similar to the strategy used by cells to control Arp2/3 complex activity and hence the spatial and temporal distribution of actin polymerization.
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