rp-120: a common endogenous substrate for insulin and IGF-1 receptor-associated tyrosine kinase activity in the highly malignant AS-30D rat hepatoma cells.
Receptors for Insulin, Epidermal Growth Factor, Platelet-Derived Growth Factor and Insulin-like Growth Factor type 1 are tyrosine-specific protein kinases. This enzymatic activity may play a role in mediating the biological actions of these peptides. It has recently been identified a Mr 120 KDa glycoprotein in rat liver plasma membranes which can be phosphorylated by the insulin receptor and by the EGF receptor in a cell-free system and by the insulin receptor in intact cultured H-35 hepatoma cells. In the present report it is shown that the solubilized Insulin-like Growth Factor type 1 receptor can phosphorylate tyrosine residues in the same 120 KDa glycoprotein from the AS-30D rat hepatoma cells.
Fanciulli
M
M
Regina Elena Institute for Cancer Research, Rome, Italy.
Paggi
M G
MG
Mancini
A
A
Del Carlo
C
C
Floridi
A
A
Taylor
S I
SI
Perrotti
N
N
D000818:Animals; D005260:Female; D007163:Immunosorbent Techniques; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D008114:Liver Neoplasms, Experimental / Q000201:enzymology*; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008862:Microsomes, Liver / Q000032:analysis; D008970:Molecular Weight; D010766:Phosphorylation; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011972:Receptor, Insulin / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D017451:Receptors, Somatomedin; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000031:analogs & derivatives / Q000378:metabolism
D007328:Insulin; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; D019000:Phosphotyrosine; D014443:Tyrosine; D007334:Insulin-Like Growth Factor I; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin