Cell adhesion and Rho small GTPases

J Cell Sci. 1999 Dec;112 ( Pt 24):4491-500.


The Rho small GTPases, Cdc42, Rac1 and Rho, are implicated in regulation of integrin-mediated cell-substratum adhesion and cadherin-mediated cell-cell adhesion. Identification and characterization of effectors of these GTPases have provided insights into their modes of action. Rho-kinase, an effector of Rho, regulates integrin-mediated cell-substratum adhesion (focal adhesion) by regulating the phosphorylation state of myosin light chain (MLC): it directly phosphorylates MLC and also inactivates myosin phosphatase. IQGAP1, an effector of Cdc42 and Rac1, regulates cadherin-mediated cell-cell adhesion by interacting with (beta)-catenin and dissociating (alpha)-catenin from the cadherin-catenins complex. Activated Cdc42 and Rac1 inhibit IQGAP1, thereby stabilizing the cadherin-catenins complex. Cdc42/Rac1 and IQGAP1 thus appear to constitute a switch that regulates cadherin-mediated cell-cell adhesion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cadherins / metabolism
  • Cell Adhesion / physiology*
  • Dimerization
  • GTP Phosphohydrolases / physiology*
  • Phosphorylation
  • Tyrosine / metabolism


  • Cadherins
  • Tyrosine
  • GTP Phosphohydrolases