Rat liver membranes contain a 120 kDa glycoprotein which serves as a substrate for the tyrosine kinases of the receptors for insulin and epidermal growth factor.
The receptors for insulin and epidermal growth factor possess tyrosine-specific protein kinase activity which may play a role in mediating the biological actions of these two peptides. We have identified a 120 kDa glycoprotein (pp120) in rat liver plasma membranes which can be phosphorylated by the insulin receptor in a cell-free system and in intact cultured hepatoma cells. In the present report, we have demonstrated in a cell-free system that solubilized epidermal growth factor receptors can phosphorylate tyrosine residues in pp120.
D000818:Animals; D002474:Cell-Free System; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D007328:Insulin / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008862:Microsomes, Liver / Q000378:metabolism; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011972:Receptor, Insulin / Q000378:metabolism*
D006023:Glycoproteins; D007328:Insulin; D008565:Membrane Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin