Cellular signaling

The mechanism by which cells receive and respond to stimuli is known as cell signaling. By understanding the fundamentals of cell signaling, tissue engineers can better direct cell behavior. This chapter outlines the paradigm of cell signaling, from signal initiation to signal transduction to gene activation. The main types of signals, receptors, and the machinery for gene activation are described and specific signaling cascades relevant to tissue engineering are outlined. For example, the G-protein-coupled receptors and the receptor tyrosine kinases are detailed, as are the TGF-ß superfamily, Wnt signaling, Rho kinase signaling, NF-?B signaling, and vitamin D signaling. The complexity of cellular signaling is underlined with examples of where it deviates from the classical descriptions of these pathways. Throughout this chapter, various means for tissue engineers to exploit these pathways to direct cell behavior are revealed. And finally, a future perspective about how tissue engineering will continue to benefit from advances in cell signaling is given.