title: Functional and structural characteristics of EGF and its receptor and their relationship to transforming proteins.
abstract: Epidermal growth factor (EGF) is a peptide which effects the growth and/or differentiated functions of many cell types. Several pieces of evidence indicate that EGF and its receptor may play a role in carcinogenesis. Functional and structural characteristics of EGF and its receptor and their relationship to transforming proteins are discussed. EGF has extensive homology with alpha-transforming growth factor (alpha-TGF), which may actually be an embryonic form of EGF. Nevertheless, both EGF and alpha-TGF elicit transformation-associated phenotypes in target cells under certain conditions. EGF effects are mediated by a receptor present on the plasma membrane. The EGF receptor is a highly complex protein having several functions in addition to binding EGF in a highly specific manner. One of these functions is to phosphorylate tyrosyl residues on certain proteins. This activity is similar to that expressed by the src family of oncogene-encoded proteins. Besides sharing functional homology the EGF receptor also exhibits structural homology to several oncogene-encoded proteins. The v-erb-B-transforming protein has a striking extent of homology (95%) to the cytoplasmic portion of the EGF receptor. These data support the concept that some aspect of EGF-stimulated metabolism is involved in cellular transformation.
mesh_terms: D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000032:analysis* / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D066246:ErbB Receptors; D006801:Humans; D008970:Molecular Weight; D009363:Neoplasm Proteins / Q000032:analysis* / Q000378:metabolism; D010455:Peptides / Q000378:metabolism / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000096:biosynthesis / Q000145:classification / Q000502:physiology; D015291:Transforming Growth Factors
chemical_list: D009363:Neoplasm Proteins; D010455:Peptides; D011956:Receptors, Cell Surface; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors; D066246:ErbB Receptors