Epidermal growth factor (EGF) is a 6045 M.W. (53 residue) polypeptide isolated from the submaxillary gland of the adult male mouse. The amino acid sequence of this growth factor has been determined. EGF stimulates the growth of epidermis and corneal epithelium in a variety of species, both in organ culture and in vivo. We plan to initiate a number of studies relating to the structure, biosynthesis, biological function, and mode of action of this polypeptide. Structural studies on EGF will include localization of the three disulfide bonds and interpretation of the circular dischroic spectra of native EGF and various chemical and enzymatic derivatives. The stimulation of the biosynthesis of EGF by androgenic hormones will be studied in organ cultures of the submaxillary gland. In the intact animal androgens induce the synthesis not only of EGF, but also of a number of other biologically active proteins (salivary renin, arginine esterase, nerve growth factor). The cellular location of the androgen induced proteins will be examined by immunocytochemical techniques. The metabolic fate of EGF will be studied using I125 labeled material. A possible biological role for EGF in the repair of the epithelium after burn wounds and corneal lesions will be examined, as well as the effects of EGF on corneal development.