Rap1: a key regulator in cell-cell junction formation

J Cell Sci. 2007 Jan 1;120(Pt 1):17-22. doi: 10.1242/jcs.03306.


Rap1 is a Ras-like small GTPase that is activated by many extracellular stimuli and strongly implicated in the control of integrin-mediated cell adhesion. Recent evidence indicates that Rap1 also plays a key role in formation of cadherin-based cell-cell junctions. Indeed, inhibition of Rap1 generates immature adherens junctions, whereas activation of Rap1 tightens cell-cell junctions. Interestingly, Rap1 guanine nucleotide exchange factors, such as C3G and PDZ-GEF, are directly linked to E-cadherin or to other junction proteins. Furthermore, several junction proteins, such as afadin/AF6 and proteins controlling the actin cytoskeleton, function as effectors of Rap1. These findings point to a role of Rap1 in spatial and temporal control of cell-cell junction formation.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Adherens Junctions / physiology*
  • Animals
  • Cell Communication / physiology*
  • rap1 GTP-Binding Proteins / physiology*


  • rap1 GTP-Binding Proteins