TY - JOUR
T1 - Identification of the major SHPTP2-binding protein that is tyrosine-phosphorylated in response to insulin
AU - Yamauchi, Keishi
AU - Ribon, Vered
AU - Saltiel, Alan R.
AU - Pessin, Jeffrey E.
PY - 1995/7/28
Y1 - 1995/7/28
N2 - Immunoprecipitation of the cytosolic Src homology 2 domain-containing protein-tyrosine phosphatase, SHPTP2, from insulin-stimulated 3T3L1 adipocytes or Chinese hamster ovary cells expressing the human insulin receptor resulted in the coimmunoprecipitation of a diffuse tyrosine-phosphorylated band in the 115-kDa protein region on SDS-polyacrylamide gels. Although platelet-derived growth factor induced the tyrosine phosphorylation of the platelet-derived growth factor receptor and SHPTP2, there was no significant increase in the coimmunoprecipitation of tyrosine-phosphorylated pp115 with SHPTP2. SHPTP2 was also associated with tyrosine-phosphorylated insulin receptor substrate-1, but this only accounted for <2% of the total immunoreactive SHPTP2 protein. Similarly, only a small fraction of the total amount of tyrosine-phosphorylated insulin receptor substrate-1 (<4%) was associated with SHPTP2. Expression and immunoprecipitation of a Myc epitope-tagged wild-type SHPTP2 (MycWT-SHPTP2) and a catalytically inactive point mutant of SHPTP2 (Myc-C/S-SHPTP2) also demonstrated an insulin-dependent association of SHPTP2 with tyrosinephosphorylated pp115. Furthermore, expression of the catalytically inactive SHPTP2 mutant resulted in a marked enhancement in the amount of coimmunoprecipitated tyrosine-phosphorylated pp115 compared with the expression of wild-type SHPTP2. These data indicate that the insulin-stimulated tyrosine-phosphorylated 115-kDa protein is the predominant in vivo SHPTP2-binding protein and that pp115 may function as a physiological substrate for the SHPTP2 proteintyrosine phosphatase.
AB - Immunoprecipitation of the cytosolic Src homology 2 domain-containing protein-tyrosine phosphatase, SHPTP2, from insulin-stimulated 3T3L1 adipocytes or Chinese hamster ovary cells expressing the human insulin receptor resulted in the coimmunoprecipitation of a diffuse tyrosine-phosphorylated band in the 115-kDa protein region on SDS-polyacrylamide gels. Although platelet-derived growth factor induced the tyrosine phosphorylation of the platelet-derived growth factor receptor and SHPTP2, there was no significant increase in the coimmunoprecipitation of tyrosine-phosphorylated pp115 with SHPTP2. SHPTP2 was also associated with tyrosine-phosphorylated insulin receptor substrate-1, but this only accounted for <2% of the total immunoreactive SHPTP2 protein. Similarly, only a small fraction of the total amount of tyrosine-phosphorylated insulin receptor substrate-1 (<4%) was associated with SHPTP2. Expression and immunoprecipitation of a Myc epitope-tagged wild-type SHPTP2 (MycWT-SHPTP2) and a catalytically inactive point mutant of SHPTP2 (Myc-C/S-SHPTP2) also demonstrated an insulin-dependent association of SHPTP2 with tyrosinephosphorylated pp115. Furthermore, expression of the catalytically inactive SHPTP2 mutant resulted in a marked enhancement in the amount of coimmunoprecipitated tyrosine-phosphorylated pp115 compared with the expression of wild-type SHPTP2. These data indicate that the insulin-stimulated tyrosine-phosphorylated 115-kDa protein is the predominant in vivo SHPTP2-binding protein and that pp115 may function as a physiological substrate for the SHPTP2 proteintyrosine phosphatase.
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U2 - 10.1074/jbc.270.30.17716
DO - 10.1074/jbc.270.30.17716
M3 - Article
C2 - 7629070
AN - SCOPUS:0029045734
SN - 0021-9258
VL - 270
SP - 17716
EP - 17722
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 30
ER -