Liposomes pp 95-103 | Cite as

The Reconstitution of Actin Polymerization on Liposomes

  • Mark Stamnes
  • Weidong Xu
Part of the Methods in Molecular Biology™ book series (MIMB, volume 606)


Membrane-associated actin polymerization is of considerable interest due to its role in cell migration and the motility of intracellular organelles. Intensive research efforts are underway to investigate the physiological role of membrane-associated actin as well as the regulation and mechanics of actin assembly. Branched actin polymerization on membranes is catalyzed by the Arp2/3 complex. Signaling events leading to the activation of the guanosine triphosphate (GTP)-binding protein Cdc42 stimulate Arp2/3-dependent actin polymerization. We have studied the role of Cdc42 at the Golgi apparatus in part by reconstituting actin polymerization on isolated Golgi membranes and on liposomes. In this manner, we showed that cytosolic proteins are sufficient for actin assembly on a phospholipid bilayer. Here we describe methods for the cell-free reconstitution of membrane-associated actin polymerization using liposomes and brain cytosol.

Key words

Liposome Actin Arp2/3 Wiscott-Aldrich syndrome protein (WASP) Cdc42 



This work was supported by NIH grant RO1 GM068674 (M.S.). The methods for preparing cytosol and liposomes have been adapted from (13, 14). We thank Heidi Hehnly for reading the manuscript.


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Copyright information

© Humana Press, a part of Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Mark Stamnes
    • 1
  • Weidong Xu
    • 1
  1. 1.Department of Molecular Physiology & Biophysics, Roy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityUSA

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