All biological processes result from integrated and concerted molecular events.
In addition, signal cascades are involved in practically all aspects of biological function, including metabolism, cell division, developmental regulation, response to environmental stimuli and stress, muscular contraction, vision, and thought. E.G. Krebs and colleagues proposed one of the first enzyme activation signaling cascades in 1966. This later discovery provided the missing piece to the puzzle of the first complete protein phosphorylation-based signal cascade. Some of these new technologies are the product of signaling research itself, whereas others are borrowed from other research areas. Chief among these has been the advent of genetic engineering and the development and availability of a broad spectrum of signaling substrates, inhibitors, analogs, agonists, and proteins.