title: Direct interaction between Shc and the platelet-derived growth factor beta-receptor.
abstract: The Src homology 2 (SH2) domain-containing Shc proteins p52shc and p46shc become phosphorylated upon activation of several tyrosine kinases and are implicated in mitogenic signal transduction. Ligand stimulation of the platelet-derived growth factor (PDGF) beta-receptor leads to autophosphorylation of tyrosine residues, which is known to mediate interactions with several SH2 domain-containing signaling molecules. In this study, we have characterized the interaction between the PDGF beta-receptor and Shc. PDGF beta-receptor coprecipitation in Shc immunoprecipitates was dependent on stimulation with PDGF-BB. The Shc SH2 domain expressed as a bacterial fusion protein bound the autophosphorylated PDGF beta-receptor. Moreover, the Shc SH2 domain could bind the autophosphorylated purified baculovirus-expressed PDGF beta-receptor intracellular domain, which indicates a direct association of Shc with the PDGF beta-receptor. Activation of the PDGF beta-receptor induced the preferential phosphorylation of p52shc. Tyrosine-phosphorylated Shc, in turn, formed a complex with the signaling molecule Grb2. Synthetic peptide analysis revealed that certain autophosphorylation sites in the PDGF beta-receptor (Tyr-579, Tyr-740, Tyr-751, and Tyr-771) were able to mediate the specific binding of the Shc SH2 domain as well as intact Shc proteins. A mutant PDGF beta-receptor in which Tyr-579 was replaced with phenylalanine showed 40% impaired association of Shc in vivo, but phosphorylation of Shc proteins was not affected. We conclude that multiple autophosphorylation sites in the PDGF beta-receptor are responsible for the binding of Shc. This is in contrast to previously characterized interactions between the PDGF beta-receptor and SH2 domain-containing proteins, which generally involve one high affinity binding site in the receptor.
authors.affiliation: Ludwig Institute for Cancer Research, Biomedical Center, Uppsala, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Yokote
authors.forename: S
authors.initials: S
authors.lastname: Mori
authors.forename: K
authors.initials: K
authors.lastname: Hansen
authors.forename: J
authors.initials: J
authors.lastname: McGlade
authors.forename: T
authors.initials: T
authors.lastname: Pawson
authors.forename: C H
authors.initials: CH
authors.lastname: Heldin
authors.forename: L
authors.initials: L
authors.lastname: Claesson-Welsh
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D000595:Amino Acid Sequence; D001665:Binding Sites; D002478:Cells, Cultured; D051380:GRB2 Adaptor Protein; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010766:Phosphorylation; D011506:Proteins / Q000378:metabolism*; D017479:Receptors, Platelet-Derived Growth Factor / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014443:Tyrosine / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D051380:GRB2 Adaptor Protein; C495948:GRB2 protein, human; D011506:Proteins; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014443:Tyrosine; D017479:Receptors, Platelet-Derived Growth Factor