title: EGF-receptor specificity for phosphotyrosine-primed substrates provides signal integration with Src.
abstract: Aberrant activation of the EGF receptor (EGFR) contributes to many human cancers by activating the Ras-MAPK pathway and other pathways. EGFR signaling is augmented by Src-family kinases, but the mechanism is poorly understood. Here, we show that human EGFR preferentially phosphorylates peptide substrates that are primed by a prior phosphorylation. Using peptides based on the sequence of the adaptor protein Shc1, we show that Src mediates the priming phosphorylation, thus promoting subsequent phosphorylation by EGFR. Importantly, the doubly phosphorylated Shc1 peptide binds more tightly than singly phosphorylated peptide to the Ras activator Grb2; this binding is a key step in activating the Ras-MAPK pathway. Finally, a crystal structure of EGFR in complex with a primed Shc1 peptide reveals the structural basis for EGFR substrate specificity. These results provide a molecular explanation for the integration of Src and EGFR signaling with downstream effectors such as Ras.
authors.affiliation: Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.|Centers for Therapeutic Innovation, Pfizer, Boston, Massachusetts, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Begley
authors.affiliation: Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.|Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Cai-hong
authors.initials: CH
authors.lastname: Yun
authors.affiliation: Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
authors.forename: Christina A
authors.initials: CA
authors.lastname: Gewinner
authors.affiliation: Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.|Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Asara
authors.affiliation: Department of Medicine, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Jared L
authors.initials: JL
authors.lastname: Johnson
authors.affiliation: Centers for Therapeutic Innovation, Pfizer, Boston, Massachusetts, USA.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Coyle
authors.affiliation: Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA.|Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Eck
authors.affiliation: Centers for Therapeutic Innovation, Pfizer, Boston, Massachusetts, USA.
authors.forename: Irina
authors.initials: I
authors.lastname: Apostolou
authors.affiliation: Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.|Department of Medicine, Weill Cornell Medical College, New York, New York, USA.
authors.forename: Lewis C
authors.initials: LC
authors.lastname: Cantley
mesh_terms: D018360:Crystallography, X-Ray; D066246:ErbB Receptors / Q000737:chemistry / Q000187:drug effects* / Q000378:metabolism*; D051380:GRB2 Adaptor Protein / Q000378:metabolism; D006801:Humans; D010455:Peptides / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D011499:Protein Processing, Post-Translational; D012680:Sensitivity and Specificity; D055765:Shc Signaling Adaptor Proteins / Q000737:chemistry / Q000378:metabolism*; D015398:Signal Transduction; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D013379:Substrate Specificity
chemical_list: D051380:GRB2 Adaptor Protein; C495948:GRB2 protein, human; D010455:Peptides; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D019000:Phosphotyrosine; C512478:EGFR protein, human; D066246:ErbB Receptors