Mutations in the cytoplasmic domain of EGF receptor affect EGF binding and receptor internalization.

摘要: Binding of epidermal growth factor (EGF) to its receptor results in a cascade events that culminate cell division. The is present on the surface two forms high and low affinity binding for EGF. EGF activates receptor's intracellular tyrosine kinase activity subsequently causes be rapidly internalized into via clathrin-coated pits. We have cloned cDNA retroviral expression vector made mutations vitro investigate function different domains. Deletion cytoplasmic sequences abolishes but not sites as well impairing ability protein internalize cells. Thus, must involved regulation are required EGF-induced internalization. A four amino acid insertion mutation at residue 708 protein-tyrosine immunoprecipitated receptor. However, this mutant exhibits both states, internalizes efficiently able cause cells undergo DNA synthesis response Another (residue 888) activity, binding, internalization mitogenic responsiveness. Finally, chimaeric composed extracellular domain v-abl region transforms Rat-I This possesses intrinsic which cannot regulated by Moreover, fails induce