Talin, a multifunctional constituent of cell-substratum attachment sites, is a high molecular weight protein (225-270 kDa) found in variety of tissues and cell types. It is localized at a subset of adherens junctions, specialized cell-cell and cell-matrix associations that are characterized by the presence of filamentous actin at the cytoplasmic face of the junctional complex. In cultured cells, talin is absent from cell-cell junctions and found predominantly at adhesion plaques and in fibrillar streaks underlying cell surface fibronectin. Talin interacts with at least two other proteins that are localized at adhesion plaques, vinculin and integrin. Talin and vinculin have been shown to interact with each other and both have been proposed to be involved in generating the transmembrane connection, between the extracellular matrix and the cytoskeleton, that occurs at adhesion plaques. At physiological ionic strength, talin is an elongate, flexible, monomeric protein with the ability to self-associate into dimers at higher protein concentrations.