Mechanisms of Fibronectin and Integrin Function during Cell Adhesion and Migration

Cells interact specifically with a variety of different extracellular molecules as they participate in embryonic development, tissue organization, wound healing, and tumor cell invasion (for review, see Hay 1991). Recent studies indicate that central elements of these dynamic interactions are specific recognition processes involving integrin receptors and a variety of extracellular ligands such as fibronectin (for general reviews, see Mosher 1989; Albelda and Buck 1990; Hynes 1990, 1992; Akiyama et al. 1990; Hemler 1990; McDonald and Mecham 1991; Ruoslahti 1991). For example, fibronectin along with other extracellular molecules serves as a migratory substrate for embryonic cells during gastrulation and neural crest cell migration; successful adhesion and migration of these cells depend on specific binding interactions between integrin receptors and recognition sites in fibronectin.