William Boyle (Molecular and Cellular Biology, Amgen Center, Thousand Oaks, Calif.; formerly at Salk Institute, La Jolla, Calif.) “lt is now clear that cells contain the molecular apparatus to induce growth in response to environmental cues and do this by transmitting intracellular signals. Transduced signals are 'read,' then manifested as both short- and long-term changes in patterns of gene expression and, ultimately, as cellular phenotype.
“At the time we initiated this study, much was known about how external cues were received at the cell membrane, how mitogenic signals were conceived, and the ultimate interpretation of signals in terms of transcriptional activation of growth response genes. However, relatively little was known about the intermediate events that occurred between signal reception at the cell surface and transcriptional activation in the distant nucleus.
“Since mitogenic signals were known to be transmitted by a cascade of protein phosphorylation, we argued that changes in patterns...