Measurement and Analysis of In Vitro Actin Polymerization

  • Lynda K. Doolittle
  • Michael K. Rosen
  • Shae B. Padrick
Part of the Methods in Molecular Biology book series (MIMB, volume 1046)


The polymerization of actin underlies force generation in numerous cellular processes. While actin polymerization can occur spontaneously, cells maintain control over this important process by preventing actin filament nucleation and then allowing stimulated polymerization and elongation by several regulated factors. Actin polymerization, regulated nucleation, and controlled elongation activities can be reconstituted in vitro, and used to probe the signaling cascades cells use to control when and where actin polymerization occurs. Introducing a pyrene fluorophore allows detection of filament formation by an increase in pyrene fluorescence. This method has been used for many years and continues to be broadly used, owing to its simplicity and flexibility. Here we describe how to perform and analyze these in vitro actin polymerization assays, with an emphasis on extracting useful descriptive parameters from kinetic data.

Key words

Actin polymerization In vitro reconstitution Biochemical assay Quantitative analysis 


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Copyright information

© Springer Science+Business Media, LLC 2013

Authors and Affiliations

  • Lynda K. Doolittle
    • 1
  • Michael K. Rosen
    • 1
  • Shae B. Padrick
    • 1
  1. 1.Department of BiophysicsUT Southwestern Medical Center and Howard Hughes Medical InstituteDallasUSA

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