title: Epidermal growth factor-induced association of the SHPTP2 protein tyrosine phosphatase with a 115-kDa phosphotyrosine protein.
abstract: Epidermal growth factor (EGF) stimulation of HepG2 and NIH 3T3 cells expressing high levels of the human EGF receptor (3T3/ER) resulted in the tyrosine phosphorylation of a 115-kDa protein that was co-immunoprecipitated with the Src homology 2 (SH2) domain containing protein tyrosine phosphatase, SHPTP2. In contrast, activation of the EGF receptor resulted in a relatively low level (< 1%) of the total SHPTP2 pool associated with the tyrosine-autophosphorylated EGF receptor itself. Similarly, quantitative immunoprecipitations also demonstrated that only trace amounts of the total EGF receptor pool were associated with SHPTP2. Further, activation of the EGF receptor did not result in any significant tyrosine phosphorylation of SHPTP2 and/or the association of the 115-kDa protein with Grb2. In comparison, activation of Jurkat cells with a T cell receptor agonist monoclonal antibody resulted in the co-immunoprecipitation of a 120-kDa tyrosine-phosphorylated protein with Grb2 and a 105-kDa protein with SHPTP2. Thus, these data have identified the 115- and 105-kDa proteins as the predominant SHPTP2-associated phosphotyrosine proteins in EGF- and T cell receptor-activated cells, respectively.
authors.affiliation: Department of Physiology and Biophysics, University of Iowa, Iowa City 52242, USA.
authors.forename: K
authors.initials: K
authors.lastname: Yamauchi
authors.forename: J E
authors.initials: JE
authors.lastname: Pessin
mesh_terms: D016475:3T3 Cells; D000818:Animals; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008113:Liver Neoplasms; D051379:Mice; D008970:Molecular Weight; D010750:Phosphoproteins / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism*; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000031:analogs & derivatives
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D010750:Phosphoproteins; D019000:Phosphotyrosine; D014443:Tyrosine; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; C516724:PTPN11 protein, human; C509249:PTPN6 protein, human; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases; C516725:Ptpn11 protein, mouse; C509248:Ptpn6 protein, mouse; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases