Interaction of crk with Myosin-1c participates in fibronectin-induced cell spreading

Int J Biol Sci. 2013 Aug 15;9(8):778-91. doi: 10.7150/ijbs.6459. eCollection 2013.


We previously reported a novel interaction between v-Crk and myosin-1c, and demonstrated that this interaction is essential for cell migration, even in the absence of p130CAS. We here demonstrate a role for Crk-myosin-1c interaction in cell adhesion and spreading. Crk-knockout (Crk ⁻/⁻) mouse embryo fibroblasts (MEFs) exhibited significantly decreased cell spreading and reduced Rac1 activity. A stroboscopic analysis of cell dynamics during cell spreading revealed that the cell-spreading deficiency in Crk⁻/⁻ MEFs was due to the short protrusion/retraction distances and long persistence times of membrane extensions. The low activity of Rac1 in Crk⁻/⁻ MEFs, which led to delayed cell spreading in these cells, is consistent with the observed defects in membrane dynamics. Reintroduction of v-Crk into Crk⁻/⁻ MEFs rescued these defects, restoring cell-spreading activity and membrane dynamics to Crk⁺/⁺ MEF levels, and normalizing Rac1 activity. Knockdown of myosin-1c by introduction of small interfering RNA resulted in a delay in cell spreading and reduced Rac1 activity to low levels, suggesting that myosin-1c also plays an essential role in cell adhesion and spreading. In addition, deletion of the v-Crk SH3 domain, which interacts with the myosin-1c tail, led to defects in cell spreading. Overexpression of the GFP-myosin-1c tail domain effectively inhibited the v-Crk-myosin-1c interaction and led to a slight decrease in cell spreading and cell surface area. Collectively, these findings suggest that the v-Crk-myosin-1c interaction, which modulates membrane dynamics by regulating Rac1 activity, is crucial for cell adhesion and spreading.

Keywords: cell adhesion; cell spreading; myosin-1c; v-Crk.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion / genetics
  • Cell Adhesion / physiology*
  • Cell Membrane / physiology*
  • Cell Movement / genetics
  • Cell Movement / physiology*
  • DNA Primers / genetics
  • Fibroblasts
  • Fibronectins / metabolism*
  • Gene Knockdown Techniques
  • Immunoblotting
  • Immunohistochemistry
  • Mice
  • Mice, Knockout
  • Myosin Type I / genetics
  • Myosin Type I / metabolism*
  • Neuropeptides / metabolism
  • Proto-Oncogene Proteins c-crk / genetics
  • Proto-Oncogene Proteins c-crk / metabolism*
  • RNA, Small Interfering / genetics
  • Stroboscopy
  • rac1 GTP-Binding Protein / metabolism


  • Crk protein, mouse
  • DNA Primers
  • Fibronectins
  • Myo1c protein, mouse
  • Neuropeptides
  • Proto-Oncogene Proteins c-crk
  • RNA, Small Interfering
  • Rac1 protein, mouse
  • Myosin Type I
  • rac1 GTP-Binding Protein