Abstract
SHP-2, a cytosolic protein tyrosine phosphatase with two SH2 domains and multiple tyrosine phosphorylation sites, contributes to signal transduction as an enzyme and/or adaptor molecule. Here we demonstrate that prolactin (PRL) stimulation of the PRL-responsive Nb2 cells, a rat lymphoma cell line, and T47D cells, a human breast cancer cell line, lead to the complex formation of SHP-2 and growth factor receptor-bound protein-2 (grb2). Using transient co-overexpression studies of the prolactin receptor (PRLR) and several tyrosine to phenylalanine mutants of SHP-2, we show that grb2 associates with SHP-2 through the C-terminal tyrosine residues of SHP-2, Y(546) and Y(584). Furthermore, in this study, we found a highly phosphorylated, 29-kDa protein (p29), a substrate of SHP-2. The recruitment of p29 to SHP-2 requires the carboxy-terminal tyrosine residues of SHP-2 (Y(546) and Y(584)). Together, our results indicate that SHP-2 may function as an adaptor molecule downstream of the PRLR and highlight a new recruitment mechanism of SHP-2 substrates.
Copyright 2002 Elsevier Science Inc.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adaptor Proteins, Signal Transducing*
-
Adaptor Proteins, Vesicular Transport / metabolism
-
Animals
-
Breast Neoplasms
-
GRB2 Adaptor Protein
-
Humans
-
Intracellular Signaling Peptides and Proteins
-
Janus Kinase 2
-
Lymphoma
-
Phosphoproteins / metabolism
-
Phosphorylation
-
Phosphotyrosine / metabolism
-
Precipitin Tests
-
Protein Tyrosine Phosphatase, Non-Receptor Type 11
-
Protein Tyrosine Phosphatases / metabolism*
-
Protein-Tyrosine Kinases / metabolism
-
Proteins / metabolism
-
Proto-Oncogene Proteins*
-
Rats
-
Receptors, Prolactin / metabolism*
-
Signal Transduction / physiology*
-
Substrate Specificity
-
Tumor Cells, Cultured
-
Tyrosine / metabolism
Substances
-
Adaptor Proteins, Signal Transducing
-
Adaptor Proteins, Vesicular Transport
-
GRB2 Adaptor Protein
-
GRB2 protein, human
-
Grb2 protein, rat
-
Intracellular Signaling Peptides and Proteins
-
Phosphoproteins
-
Proteins
-
Proto-Oncogene Proteins
-
Receptors, Prolactin
-
Phosphotyrosine
-
Tyrosine
-
Protein-Tyrosine Kinases
-
JAK2 protein, human
-
Jak2 protein, rat
-
Janus Kinase 2
-
PTPN11 protein, human
-
Protein Tyrosine Phosphatase, Non-Receptor Type 11
-
Protein Tyrosine Phosphatases
-
Ptpn11 protein, rat