title: c-Cbl is inducibly tyrosine-phosphorylated by epidermal growth factor stimulation in fibroblasts, and constitutively tyrosine-phosphorylated and associated with v-Src in v-src-transformed fibroblasts.
abstract: The c-cbl gene was cloned as the cellular homolog of the v-cbl oncogene that is the transforming component of a murine tumorigenic retrovirus, CAS NS-1, though the biological roles of c-Cbl remain to be elucidated. We have previously reported that c-Cbl is implicated in the signal transduction triggered by granulocyte-macrophage colony-stimulating factor or erythropoietin in hematopoietic cells. Here, we observed tyrosine phosphorylation of C-cbl in cells expressing epidermal growth factor receptor depending on EGF stimulation and in v-src transformed cells. Furthermore, c-Cbl was revealed to associate with v-Src in vivo. By means of binding experiments using glutathione S-transferase fusion proteins, we have found that the SH2 and SH3 domains of many proteins bind to c-Cbl. These findings strongly suggest that c-Cbl is implicated in a wide variety of signal transduction pathways, including those of EGF receptor and Src protein, as well as in the signaling pathways of hematopoietic cells.
authors.affiliation: Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo.
authors.forename: H
authors.initials: H
authors.lastname: Odai
authors.forename: K
authors.initials: K
authors.lastname: Sasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Hanazono
authors.forename: H
authors.initials: H
authors.lastname: Ueno
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: K
authors.initials: K
authors.lastname: Miyagawa
authors.forename: K
authors.initials: K
authors.lastname: Mitani
authors.forename: Y
authors.initials: Y
authors.lastname: Yazaki
authors.forename: H
authors.initials: H
authors.lastname: Hirai
mesh_terms: D016475:3T3 Cells / Q000187:drug effects / Q000378:metabolism; D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002461:Cell Line, Transformed; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D051380:GRB2 Adaptor Protein; D006801:Humans; D007938:Leukemia / Q000473:pathology; D051379:Mice; D015688:Oncogene Protein pp60(v-src) / Q000378:metabolism*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D050721:Proto-Oncogene Proteins c-cbl; D015398:Signal Transduction; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051380:GRB2 Adaptor Protein; C495948:GRB2 protein, human; C495949:Grb2 protein, mouse; D011506:Proteins; D011518:Proto-Oncogene Proteins; D014443:Tyrosine; D004815:Epidermal Growth Factor; D050721:Proto-Oncogene Proteins c-cbl; D044767:Ubiquitin-Protein Ligases; D066246:ErbB Receptors; D015688:Oncogene Protein pp60(v-src); C067419:CBL protein, human; C493849:Cbl protein, mouse