ABSTRACT
The binding of integrins to extracellular matrix (ECM) proteins promotes their aggregation on the plane of the plasma membrane and their interaction with cytoskeletal elements as well as signaling molecules. This chapter describes methods used in our laboratory to examine integrin-mediated She signaling. It provides methods to analyze the constitutive association of Integrins with caveolin-1 and that of caveolin-1 with Fyn, as well as methods to examine the activation of the fraction of Fyn associated with caveolin-1, the recruitment and tyrosine phosphorylation of She, and the association of She with Grb2 in response to integrin ligation. Integrin-mediated signaling can be activated: 1, by plating the cells onto dishes coated with ECM components or anti-integrin antibodies; 2, by incubating the cells in suspension with polystyrene beads coated with anti-integrin antibodies; or 3) by incubating the cells in suspension with soluble anti-integrin antibodies followed by appropriate secondary antibodies.
