title: Integrin adhesions: who's on first? What's on second? Connections between FAK and talin.
abstract: Cell migration requires the coordination of adhesion site assembly and turnover. Canonical models for nascent adhesion formation postulate that integrin binding to extracellular matrix (ECM) proteins results in the rapid recruitment of cytoskeletal proteins such as talin and paxillin to integrin cytoplasmic domains. It is thought that integrin-talin clusters recruit and activate tyrosine kinases such as focal adhesion kinase (FAK). However, the molecular connections of this linkage remain unresolved. Our recent findings support an alternative model whereby FAK recruits talin to new sites of β1 integrin-mediated adhesion in mouse embryonic fibroblasts and human ovarian carcinoma cells. This is dependent on a direct binding interaction between FAK and talin and occurs independently of direct talin binding to β1 integrin. Herein, we discuss differences between nascent and mature adhesions, interactions between FAK, talin and paxillin, possible mechanisms of FAK activation and how this FAK-talin complex may function to promote cell motility through increased adhesion turnover.
authors.affiliation: Department of Reproductive Medicine, Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093 USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Lawson
authors.forename: David D
authors.initials: DD
authors.lastname: Schlaepfer
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002460:Cell Line; D005353:Fibronectins / Q000378:metabolism; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism*; D006801:Humans; D016023:Integrins / Q000378:metabolism / Q000502:physiology*; D008958:Models, Molecular; D021381:Protein Transport; D016608:Talin / Q000378:metabolism*
chemical_list: D015815:Cell Adhesion Molecules; D005353:Fibronectins; D016023:Integrins; D016608:Talin; D051416:Focal Adhesion Protein-Tyrosine Kinases