Selective Integrin Endocytosis is Driven by Alpha Chain:Ap2 InteractionsDe Franceschi, N., Arjonen, A., Elkhatib, N., Denessiouk, K., Wrobel, A.G., Wilson, T.A., Pouwels, J., Montagnac, G., Owen, D.J., Ivaska, J.
(2016) Nat.Struct.Mol.Biol. 23: 172
- PubMed: 26779610
- DOI: 10.1038/nsmb.3161
- PubMed Abstract:
Integrins are heterodimeric cell-surface adhesion molecules comprising one of 18 possible α-chains and one of eight possible β-chains. They control a range of cell functions in a matrix- and ligand-specific manner. Integrins can be internalized by cl ...
Integrins are heterodimeric cell-surface adhesion molecules comprising one of 18 possible α-chains and one of eight possible β-chains. They control a range of cell functions in a matrix- and ligand-specific manner. Integrins can be internalized by clathrin-mediated endocytosis (CME) through β subunit-based motifs found in all integrin heterodimers. However, whether specific integrin heterodimers can be selectively endocytosed was unknown. Here, we found that a subset of α subunits contain an evolutionarily conserved and functional YxxΦ motif directing integrins to selective internalization by the most abundant endocytic clathrin adaptor, AP2. We determined the structure of the human integrin α4-tail motif in complex with the AP2 C-μ2 subunit and confirmed the interaction by isothermal titration calorimetry. Mutagenesis of the motif impaired selective heterodimer endocytosis and attenuated integrin-mediated cell migration. We propose that integrins evolved to enable selective integrin-receptor turnover in response to changing matrix conditions.
Turku Centre for Biotechnology, University of Turku, Turku, Finland.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1170, Villejuif, France.,Institut Gustave Roussy, Villejuif, France.,Department of Biochemistry and Food Chemistry, University of Turku, Turku, Finland.,Department of Biosciences, Åbo Akademi University, Turku, Finland.,Department of Clinical Biochemistry, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK.