Cellular motility driven by assembly and disassembly of actin filaments

Cell. 2003 Feb 21;112(4):453-65. doi: 10.1016/s0092-8674(03)00120-x.

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 gamma 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.

Publication types

  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Actin Depolymerizing Factors
  • Actins / chemistry
  • Actins / metabolism
  • Actins / physiology*
  • Adenosine Diphosphate / metabolism
  • Adenosine Triphosphate / metabolism
  • Animals
  • Cattle
  • Cell Division
  • Cell Membrane / metabolism
  • Cell Movement*
  • Cell Nucleus / metabolism
  • Crystallography, X-Ray
  • Dendrites / metabolism
  • Keratinocytes / ultrastructure
  • Microfilament Proteins / metabolism
  • Models, Biological
  • Models, Molecular
  • Phosphates / metabolism
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Signal Transduction*

Substances

  • Actin Depolymerizing Factors
  • Actins
  • Microfilament Proteins
  • Phosphates
  • Adenosine Diphosphate
  • Adenosine Triphosphate