Actin network growth under load

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Otger Campàs - , Harvard University (Author)
  • L. Mahadevan - , Harvard University (Author)
  • Jean Franois Joanny - , Sorbonne Université (Author)

Abstract

Many processes in eukaryotic cells, including the crawling motion of the whole cell, rely on the growth of branched actin networks from surfaces. In addition to their well-known role in generating propulsive forces, actin networks can also sustain substantial pulling loads thanks to their persistent attachment to the surface from which they grow. The simultaneous network elongation and surface attachment inevitably generate a force that opposes network growth. Here, we study the local dynamics of a growing actin network, accounting for simultaneous network elongation and surface attachment, and show that there exist several dynamical regimes that depend on both network elasticity and the kinetic parameters of actin polymerization. We characterize this in terms of a phase diagram and provide a connection between mesoscopic theories and the microscopic dynamics of an actin network at a surface. Our framework predicts the onset of instabilities that lead to the local detachment of the network and translate to oscillatory behavior and waves, as observed in many cellular phenomena and in vitro systems involving actin network growth, such as the saltatory dynamics of actin-propelled oil drops.

Details

Original languageEnglish
Pages (from-to)1049-1058
Number of pages10
JournalBiophysical journal
Volume102
Issue number5
Publication statusPublished - 7 Mar 2012
Peer-reviewedYes
Externally publishedYes

External IDs

PubMed 22404927

Keywords

ASJC Scopus subject areas