1. Academic Validation
  2. Disruption of focal adhesions by integrin cytoplasmic domain-associated protein-1 alpha

Disruption of focal adhesions by integrin cytoplasmic domain-associated protein-1 alpha

  • J Biol Chem. 2003 Feb 21;278(8):6567-74. doi: 10.1074/jbc.M211258200.
Daniel Bouvard 1 Lucile Vignoud Sandra Dupé-Manet Nadia Abed Henri-Noël Fournier Carole Vincent-Monegat Saverio Francesco Retta Reinhard Fassler Marc R Block
Affiliations

Affiliation

  • 1 Laboratoire d'Etude de la Differenciation et de l'Adhérence Cellulaires, Unité Mixte de Recherche UJF/CNRS 5538, Institut Albert Bonniot, Faculte de Médecine de Grenoble, La Tronche F38706 cedex, France.
Abstract

Regulation of Integrin affinity and clustering plays a key role in the control of cell adhesion and migration. The protein ICAP-1 alpha (Integrin cytoplasmic domain-associated protein-1 alpha) binds to the cytoplasmic domain of the beta(1A) Integrin and controls cell spreading on fibronectin. Here, we demonstrate that, despite its ability to interact with beta(1A) Integrin, ICAP-1 alpha is not recruited in focal adhesions, whereas it is colocalized with the Integrin at the ruffling edges of the cells. ICAP-1 alpha induced a rapid disruption of focal adhesions, which may result from the ability of ICAP-1 alpha to inhibit the association of beta(1A) Integrin with talin, which is crucial for the assembly of these structures. ICAP-1 alpha-mediated dispersion of beta(1A) integrins is not observed with beta(1D) integrins that do not bind ICAP. This strongly suggests that ICAP-1 alpha action depends on a direct interaction between ICAP-1 alpha and the cytoplasmic domain of the beta(1) chains. Altogether, these results suggest that ICAP-1 alpha plays a key role in cell adhesion by acting as a negative regulator of beta(1) Integrin avidity.

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