Function
Functions as component of the Arp2/3 complex which is involved in regulation of actin polymerization and together with an activating nucleation-promoting factor (NPF) mediates the formation of branched actin networks. Seems to contact the pointed end of the daughter actin filament. The Arp2/3 complex is involved in organizing the actin system in cell motility and chemotaxis, in phagocytosis and macropinocytosis, at late steps of endosome processing, and in mitosis. In concert with a group of other proteins, the Arp2/3 complex plays a general role in the rapid activation and adaptation of the actin system to its multiple functions.