First Author | Vogel W | Year | 1996 |
Journal | Cell Growth Differ | Volume | 7 |
Issue | 12 | Pages | 1589-97 |
PubMed ID | 8959326 | Mgi Jnum | J:200354 |
Mgi Id | MGI:5508314 | Citation | Vogel W, et al. (1996) Multiple in vivo phosphorylated tyrosine phosphatase SHP-2 engages binding to Grb2 via tyrosine 584. Cell Growth Differ 7(12):1589-97 |
abstractText | SHP-2 (also named PTP1D, syp, or SH-PTP2) has been identified as a phosphotyrosine phosphatase comprising two src-homology-2 (SH2) domains. Upon growth factor stimulation, SHP-2 becomes tyrosine phosphorylated, thereby increasing its catalytic activity. Here, we identified SHP-2 to be phosphorylated on multiple tyrosine residues in response to different stimuli and unmasked the carboxyl-terminal tyrosine 584 as a major phosphorylation site in human cell lines. Tyrosine 584 shares, together with tyrosine 546, the consensus sequence pY-X-N-X, a characteristic of potential binding sites for the SH2 domain of growth factor receptor-bound protein 2 (Grb2). We show here that mutation of tyrosine 584, but not tyrosine 546, to phenylalanine totally abolished the binding of Grb2 to SHP-2. By using a systematic mutagenesis approach, phosphorylation of additional tyrosines in each of the SH2 domains of SHP-2 was detected after coexpression of epidermal growth factor receptor, but not after coexpression of platelet-derived growth factor receptor, whereas tyrosine 263 located in the interspace between SH2 and catalytic domain appears to be exclusively recognized by platelet-derived growth factor receptor. Immunoprecipitation of SHP-2 from a panel of mammary carcinoma cell lines copurifies several tyrosine phosphorylated proteins; the most prominent band has an apparent molecular weight of M(r) 115,000. |