epidermal growth factor

Abstract

The existence in both mouse and man of epidermal growth factors that have similar chemical characteristics and exhibit identical biological activities indicates that these polypeptides have been retained throughout a long evolutionary process and probably have a function of general significance in nature. The conservation of specific receptors for epidermal growth factors in a wide variety of cells from diverse species supports this idea. Of the growth factors that have been purified to date, epidermal growth factor (EGF) is one of the most biologically potent and best characterized as to its physical, chemical, and biological properties. EGF clearly stimulates the proliferation of epidermal and epithelial tissues in animals, and cell culture studies suggest that additional cell types might be responsive in vivo. Current research concerning epidermal growth factor is oncentrated mainly on describing the growth factor's interaction with plasma membrane receptors and its subsequent internalization and degradation, analyzing the enhanced phosphorylation of membrane proteins induced by EGF in vitro, determining the sequence of biochemical events in intact cells that lead to cell proliferation, and defining the physiological role of endogenous EGF in mammalian biology.