Generation of branched actin networks: assembly and regulation of the N-WASP and WAVE molecular machines

Bioessays. 2010 Feb;32(2):119-31. doi: 10.1002/bies.200900123.


The Arp2/3 complex is a molecular machine that generates branched actin networks responsible for membrane remodeling during cell migration, endocytosis, and other morphogenetic events. This machine requires activators, which themselves are multiprotein complexes. This review focuses on recent advances concerning the assembly of stable complexes containing the most-studied activators, N-WASP and WAVE proteins, and the level of regulation that is provided by these complexes. N-WASP is the paradigmatic auto-inhibited protein, which is activated by a conformational opening. Even though this regulation has been successfully reconstituted in vitro with isolated N-WASP, the native dimeric complex with a WIP family protein has unique additional properties. WAVE proteins are part of a pentameric complex, whose basal state and activated state when bound to the Rac GTPase were recently clarified. Moreover, this review attempts to put together diverse observations concerning the WAVE complex in the conceptual frame of an in vivo assembly pathway that has gained support from the recent identification of a precursor.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Actin-Related Protein 2-3 Complex / genetics
  • Actin-Related Protein 2-3 Complex / metabolism
  • Actin-Related Protein 2-3 Complex / physiology
  • Actins / metabolism*
  • Animals
  • Humans
  • Models, Biological
  • Wiskott-Aldrich Syndrome Protein Family / genetics
  • Wiskott-Aldrich Syndrome Protein Family / metabolism*
  • Wiskott-Aldrich Syndrome Protein, Neuronal / genetics
  • Wiskott-Aldrich Syndrome Protein, Neuronal / metabolism*


  • Actin-Related Protein 2-3 Complex
  • Actins
  • Wiskott-Aldrich Syndrome Protein Family
  • Wiskott-Aldrich Syndrome Protein, Neuronal