title: αV-class integrins exert dual roles on α5β1 integrins to strengthen adhesion to fibronectin.
abstract: Upon binding to the extracellular matrix protein, fibronectin, αV-class and α5β1 integrins trigger the recruitment of large protein assemblies and strengthen cell adhesion. Both integrin classes have been functionally specified, however their specific roles in immediate phases of cell attachment remain uncharacterized. Here, we quantify the adhesion of αV-class and/or α5β1 integrins expressing fibroblasts initiating attachment to fibronectin (≤120 s) by single-cell force spectroscopy. Our data reveals that αV-class integrins outcompete α5β1 integrins. Once engaged, αV-class integrins signal to α5β1 integrins to establish additional adhesion sites to fibronectin, away from those formed by αV-class integrins. This crosstalk, which strengthens cell adhesion, induces α5β1 integrin clustering by RhoA/ROCK/myosin-II and Arp2/3-mediated signalling, whereas overall cell adhesion depends on formins. The dual role of both fibronectin-binding integrin classes commencing with an initial competition followed by a cooperative crosstalk appears to be a basic cellular mechanism in assembling focal adhesions to the extracellular matrix.
authors.affiliation: Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland.
authors.forename: Mitasha
authors.initials: M
authors.lastname: Bharadwaj
authors.affiliation: Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland.
authors.forename: Nico
authors.initials: N
authors.lastname: Strohmeyer
authors.affiliation: Max Planck Institute of Biochemistry, Department of Molecular Medicine, 82152 Martinsried, Germany.
authors.forename: Georgina P
authors.initials: GP
authors.lastname: Colo
authors.affiliation: Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland.
authors.forename: Jonne
authors.initials: J
authors.lastname: Helenius
authors.affiliation: Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland.
authors.forename: Niko
authors.identifier: 0000-0002-0573-6119
authors.initials: N
authors.lastname: Beerenwinkel
authors.affiliation: Max Planck Institute of Biochemistry, Department of Molecular Medicine, 82152 Martinsried, Germany.|Comprehensive Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, Oberschleißheim 85764, Germany.
authors.forename: Herbert B
authors.identifier: 0000-0003-1914-3215
authors.initials: HB
authors.lastname: Schiller
authors.affiliation: Max Planck Institute of Biochemistry, Department of Molecular Medicine, 82152 Martinsried, Germany.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Fässler
authors.affiliation: Eidgenössische Technische Hochschule (ETH) Zurich, Department of Biosystems Science and Engineering, 4058 Basel, Switzerland.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Müller
mesh_terms: D051376:Actin-Related Protein 2-3 Complex / Q000378:metabolism; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology*; D005109:Extracellular Matrix / Q000378:metabolism; D005347:Fibroblasts / Q000502:physiology*; D005353:Fibronectins / Q000378:metabolism*; D022001:Focal Adhesions / Q000378:metabolism; D039081:Integrin alpha5beta1 / Q000378:metabolism*; D039564:Integrin alphaV / Q000378:metabolism*; D051379:Mice; D024462:Myosin Type II / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D015398:Signal Transduction / Q000502:physiology; D059010:Single-Cell Analysis; D013057:Spectrum Analysis / Q000379:methods; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D051376:Actin-Related Protein 2-3 Complex; D005353:Fibronectins; D039081:Integrin alpha5beta1; D039564:Integrin alphaV; D024462:Myosin Type II; D020742:rhoA GTP-Binding Protein