Contact guidance - Modes of Cell Movement
Besides chemical / ionic factors that regulate cell movement in developing embryos, physical factors as well appear to play a role in morphogenetic processes. A phenomenon called contact guidance effects cell movements in cultures. The cell is affected by the physical surface over which it passes and is directed towards its location. Weiss (1934) demonstrated that cells can detect discontinuities in their substratum and migrate after aligning themselves together such features as fibers.
They could even move along scratches at the bottom of petridish. In a recent study Harris (1980) displayed that fibroblasts cultured on silicone rubber or collagen change the shape of the substrate through the stress generated by them, and move along such changed substrate fields. Contact guidance is assumed to be the cause for the migration of mesenchymal cells inside the fish fin.