Modeling the formation of in vitro filopodia

K. C. Lee, A. Gopinathan, J. M. Schwarz

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


Filopodia are bundles of actin filaments that extend out ahead of the leading edge of a crawling cell to probe its upcoming environment. In vitro experiments (Vignjevic et al. in J Cell Biol 160:951-962, 2003) have determined the minimal ingredients required for the formation of filopodia from the dendritic-like morphology of the leading edge. We model these experiments using kinetic aggregation equations for the density of growing bundle tips. In mean field, we determine the bundle size distribution to be broad for bundle sizes smaller than a characteristic bundle size above which the distribution decays exponentially. Two-dimensional simulations incorporating both bundling and cross-linking measure a bundle size distribution that agrees qualitatively with mean field. The simulations also demonstrate a nonmonotonicity in the radial extent of the dendritic region as a function of capping protein concentration, as was observed in experiments, due to the interplay between percolation and the ratcheting of growing filaments off a spherical obstacle.

Original languageEnglish (US)
Pages (from-to)229-261
Number of pages33
JournalJournal of Mathematical Biology
Issue number2
StatePublished - Aug 2011


  • Filopodia
  • Kinetic aggregation
  • Nonequilibrium actin bundling

ASJC Scopus subject areas

  • Modeling and Simulation
  • Agricultural and Biological Sciences (miscellaneous)
  • Applied Mathematics


Dive into the research topics of 'Modeling the formation of in vitro filopodia'. Together they form a unique fingerprint.

Cite this