Integrins and signal transduction.

Integrins are dynamic cell-surface receptors that provide a physical link between the extracellular matrix and the cell cytoskeleton. The interaction of integrins with extracellular matrix ligands also results in the generation of intracellular signals that regulate cell survival and growth, cell differentiation, and cell motility. The signaling pathways regulated by integrins are both diverse and complex, and involve cross-talk among multiple pathways. An added level of complexity resides in the findings that intracellular signals generated by a variety of agonists can modulate cell adhesion by regulating integrin-matrix interactions. The identification and functional characterization of integrin receptor-proximal components involved in this fascinating "inside-out" and "outside-in" signal transduction remains an area of intense investigation. This review focuses on recent advances in this area.