Cell communication networks: epidermal growth factor receptor transactivation as the paradigm for interreceptor signal transmission

Communication between different cellular signaling systems has emerged as a common principle that enables cells to integrate a multitude of signals fr om its environment. Transactivation of the epidermal growth factor receptor (EGFR) represents the paradigm for cross-talk between G protein-coupled re ceptors (GPCRs) and receptor tyrosine kinases (RTKs), The recent identifica tion of Zn2+-dependent metalloproteinases and transmembrane growth factor p recursors as critical elements in GPCR-induced EGFR transactivation pathway s has defined new components of a cellular communication network of rapidly increasing complexity. Further elucidation of the molecular details of the EGFR transactivation mechanism will provide new understanding of its relev ance for normal physiological processes and their pathophysiological deviat ions.