Both SH2 domains are involved in interaction of SHP-1 with the epidermal growth factor receptor but cannot confer receptor-directed activity to SHP-1/SHP-2 chimera.
The previously demonstrated functional and physical interaction of the SH2 domain protein-tyrosine phosphatase SHP-1 with the epidermal growth factor (EGF) receptor (Tomic, S., Greiser, U., Lammers, R., Kharitonenkov, A., Imyanitov, E., Ullrich, A., and Böhmer, F. D. (1995) J. Biol. Chem. 270, 21277-21284) was investigated with respect to the involved structural elements of SHP-1. Various mutants of SHP-1 were transiently expressed in 293 or COS-7 cells and analyzed for their capacity to associate with immobilized autophosphorylated EGF receptor in vitro and to dephosphorylate coexpressed EGF receptor in intact cells. Inactivating point mutation of the C-terminal SH2 domain reduced the association weakly, point mutation of the N-terminal SH2 domain reduced association strongly and the respective double mutation abolished association totally. The capacity of SHP-1 to dephosphorylate coexpressed EGF receptor was impaired by all point mutations. Truncation of the N-terminal or of both SH2 domains strongly reduced or abolished association, respectively, but the truncated SHP-1 derivatives still dephosphorylated coexpressed EGF receptor effectively. Various chimeric protein-tyrosine phosphatases constructed from SHP-1 and the closely homologous SHP-2 dephosphorylated the EGF receptor when they contained the catalytic domain of SHP-1. As native SHP-2, the chimera lacked activity toward the receptor when they contained the catalytic domain of SHP-2, despite their capacity to associate with the receptor and to dephosphorylate an artificial phosphopeptide. We conclude that the differential interaction of SHP-1 and SHP-2 with the EGF receptor is due to the specificity of the respective catalytic domains rather than to the specificity of the SH2 domains. Functional interaction of native SHP-1 with the EGF receptor requires association mediated by both SH2 domains.
Tenev
T
T
Max-Planck Society, Research Unit "Molecular Cell Biology," Medical Faculty, Friedrich-Schiller University, Drackendorfer Str. 1, D-07747 Jena, Germany.
Keilhack
H
H
Tomic
S
S
Stoyanov
B
B
Stein-Gerlach
M
M
Lammers
R
R
Krivtsov
A V
AV
Ullrich
A
A
Böhmer
F D
FD
D000818:Animals; D019556:COS Cells; D002874:Chromosome Mapping; D066246:ErbB Receptors / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D016296:Mutagenesis; D010766:Phosphorylation; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics* / Q000378:metabolism; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; D014162:Transfection; D018909:src Homology Domains
D047908:Intracellular Signaling Peptides and Proteins; D011993:Recombinant Fusion Proteins; 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; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases