The complexity in regulating the expression of tenascins

AbstractThe tenascins are a growing family of extracellular matrix proteins of typical multidomain structure. The prototype to be discovered was tenascin‐C. It shows a highly regulated expression pattern during embryonic development and is often transiently associated with morphogenetic tissue interactions during organogenesis. In the adult organism reexpression of tenascin‐C occurs in tumors and many other pathological conditions. Tenascin‐C expression can be regulated by many different growth factors and hormones. Furthermore, mechanical strain exerted by fibroblasts seems to induce the expression of tenascin‐C. This could represent a mechanism of translating mechanical forces into protein patterns, a step of potential relevance in the organization of embryogenesis. Tenascin‐C as well as tenascin‐R are believed to counteract the cell adhesion and spreading activity of fibronectin, thereby facilitating cell movement.