Eps8, a substrate for the epidermal growth factor receptor kinase, enhances EGF‐dependent mitogenic signals.

摘要: Abstract A method which allows direct cloning of intracellular substrates for receptor tyrosine kinases (RTKs) was developed. By applying this technique to the study epidermal growth factor (EGFR) signaling pathway, we have isolated a cDNA, designated eps8, predicts approximately 92 kDa protein containing an SH3 domain. Eps8 also contains putative nuclear targeting sequence. Antibodies specific eps8 gene product recognize M(r) 97 and minor 68 component, are closely related, as demonstrated by V8 proteolytic mapping. The is tyrosine-phosphorylated in vivo following EGF stimulation intact cells associates with EGFR, despite lack functional SH2 Several other RTKs able phosphorylate p97eps8. Thus, represents novel substrate RTKs. Adoptive expression cDNA fibroblastic or hematopoietic target expressing EGFR resulted increased mitogenic response EGF, implicating control signals.