Fibronectin and the Cytoskeleton

Abstract

The involvement of FN in adhesion and cytoskeletal organization (Chapters 8 and 9) suggested that FN might also affect cell migration, which involves both cell—substratum adhesion and the cytoskeleton. A direct test of this hypothesis showed it to be true; purified FN promoted the migration of a variety of cultured cell lines (Fig. 10-1, Ali and Hynes, 1978a). The effect was dose-dependent and was inhibited by treatment of the FN preparations with gelatin-Sepharose or anti-FN antibodies. Migration was promoted either when Fn was added directly to the cell cultures or when the surfaces were precoated with FN. Subsequently, Schor et al (1981a, b) showed that Fn promoted migration of hamster melanoma and CHO cells into three-dimentional collagen gels and Couchman et al (1982) showed that both exogenous pFN and endogenous cFN were necessary for the migration of chick fibroblasts out of explants. Although all these studies clearly demonstrated stimulation of cell migration by cFN or pFN, the experimental systems were not suitable for the study of directional migration.