Cdc42 and Rac small G proteins activated by trans-interactions of nectins are involved in activation of c-Jun N-terminal kinase, but not in association of nectins and cadherin to form adherens junctions, in fibroblasts

Genes Cells. 2003 May;8(5):481-91. doi: 10.1046/j.1365-2443.2003.00649.x.


Background: Nectins are Ca2+-independent immunoglobulin-like cell-cell adhesion molecules which associate with cadherins to form adherens junctions (AJs) in epithelial cells and fibroblasts. Nectin-1 and -3 are members of the nectin family which most strongly trans-interact, causing cell-cell adhesion. The trans-interaction between nectin-1 and -3 induces the activation of both Cdc42 and Rac small G proteins in epithelial cells. We studied the roles of Cdc42 and Rac activated in this way in L fibroblasts stably expressing both nectin-1 and E-cadherin (nectin-1-EL cells).

Results: The trans-interaction between nectin-1 and -3 induced the activation of Cdc42 and Rac in nectin-1-EL cells. Cdc42, and presumably Rac, activated in this way, induced the activation of c-Jun N-terminal kinase (JNK), but not p38 mitogen-activated protein (MAP) kinase or extracellular signal-regulated kinase (ERK). Cdc42 or Rac was not essential for the association of nectin-1 and E-cadherin to form AJs. Reorganization of the actin cytoskeleton was not required for the association of nectin-1 and E-cadherin.

Conclusion: These results indicate that Cdc42 and Rac activated by the trans-interaction of nectins selectively induce the activation of JNK, but are not essential for the association of nectins and cadherin to form AJs in fibroblasts.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adherens Junctions / metabolism
  • Androstadienes / pharmacology
  • Animals
  • Cadherins / metabolism*
  • Cell Adhesion
  • Cell Adhesion Molecules / metabolism*
  • Cell Line
  • Enzyme Inhibitors / pharmacology
  • Fibroblasts / metabolism
  • Green Fluorescent Proteins
  • Image Processing, Computer-Assisted
  • JNK Mitogen-Activated Protein Kinases
  • Luminescent Proteins / metabolism
  • Mice
  • Microscopy, Electron, Scanning
  • Mitogen-Activated Protein Kinases / metabolism*
  • Nectins
  • Phosphoinositide-3 Kinase Inhibitors
  • Pseudopodia
  • Transfection
  • Wortmannin
  • cdc42 GTP-Binding Protein / metabolism*
  • p38 Mitogen-Activated Protein Kinases
  • rac GTP-Binding Proteins / metabolism*


  • Androstadienes
  • Cadherins
  • Cell Adhesion Molecules
  • Enzyme Inhibitors
  • Luminescent Proteins
  • Nectin1 protein, mouse
  • Nectins
  • Phosphoinositide-3 Kinase Inhibitors
  • Green Fluorescent Proteins
  • JNK Mitogen-Activated Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • cdc42 GTP-Binding Protein
  • rac GTP-Binding Proteins
  • Wortmannin