Fig. 1.

A schematic diagram illustrating the basic principles of dynamic reciprocity between neighboring cells and their extracellular environment. Mechanical and biochemical signals received at points of cell–cell or cell–ECM contact are transduced to the nucleus by transmembrane receptors, signaling molecules, and cytoskeletal components where they initiate nuclear events resulting in the expression of specific gene products that are excreted back into the extracellular milieu. Green arrows represent the bidirectional flow of mechanical and biochemical signals between the ECM and the nucleus. RTKs represent receptor tyrosine kinase. (Modified, with permission, from Bissell et al., 2005.) (See Color Insert.)