EPIDERMAL GROWTH-FACTOR STIMULATES THE TYROSINE PHOSPHORYLATION OF SHPS-1 AND ASSOCIATION OF SHPS-1 WITH SHP-2, A SH2 DOMAIN-CONTAINING PROTEIN-TYROSINE-PHOSPHATASE

SHPS-1 is a 120 kDa glycosylated receptor-like protein that contains i mmunoglobulin-like domains in its extracellular region and four potent ial tyrosine phosphorylation for SH2 domain binding sites in its cytop lasmic region. Epidermal growth factor (EGF) stimulated the rapid tyro sine phosphorylation of SHPS-1 and subsequent association of SHPS-1 wi th SHP-2, a protein tyrosine phosphatase containing SH2 domains, in Ch inese hamster ovary cells overexpressing human EGF receptors. In the c ells overexpressing SHPS-1, the tyrosine phosphorylation of SHPS-1 was more evident than that observed in parent cells. However, overexpress ion of SHPS-1 alone did not affect the activation of MAP kinase in res ponse to EGF. These results suggest that SHPS-1 may be involved in the recruitment of SHP-2 from the cytosol to the plasma membrane in respo nse to EGF. (C) 1997 Academic Press.