title: Rap1: a key regulator in cell-cell junction formation.
abstract: 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.
authors.affiliation: Department of Physiological Chemistry and Centre for Biomedical Genetics, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Matthijs R H
authors.initials: MR
authors.lastname: Kooistra
authors.forename: Nadia
authors.initials: N
authors.lastname: Dubé
authors.forename: Johannes L
authors.initials: JL
authors.lastname: Bos
mesh_terms: D022005:Adherens Junctions / Q000502:physiology*; D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D020827:rap1 GTP-Binding Proteins / Q000502:physiology*
chemical_list: D020827:rap1 GTP-Binding Proteins