title: Directed network wiring identifies a key protein interaction in embryonic stem cell differentiation.
abstract: Cell signaling depends on dynamic protein-protein interaction (PPI) networks, often assembled through modular domains each interacting with multiple peptide motifs. This complexity raises a conceptual challenge, namely to define whether a particular cellular response requires assembly of the complete PPI network of interest or can be driven by a specific interaction. To address this issue, we designed variants of the Grb2 SH2 domain ("pY-clamps") whose specificity is highly biased toward a single phosphotyrosine (pY) motif among many potential pYXNX Grb2-binding sites. Surprisingly, directing Grb2 predominantly to a single pY site of the Ptpn11/Shp2 phosphatase, but not other sites tested, was sufficient for differentiation of the essential primitive endoderm lineage from embryonic stem cells. Our data suggest that discrete connections within complex PPI networks can underpin regulation of particular biological events. We propose that this directed wiring approach will be of general utility in functionally annotating specific PPIs.
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: Norihisa
authors.initials: N
authors.lastname: Yasui
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
authors.forename: Greg M
authors.initials: GM
authors.lastname: Findlay
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
authors.forename: Gerald D
authors.initials: GD
authors.lastname: Gish
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
authors.forename: Marilyn S
authors.initials: MS
authors.lastname: Hsiung
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
authors.forename: Monika
authors.initials: M
authors.lastname: Tucholska
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada.
authors.forename: Lorne
authors.initials: L
authors.lastname: Taylor
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: Louis
authors.initials: L
authors.lastname: Smith
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: W Clifford
authors.initials: WC
authors.lastname: Boldridge
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
authors.forename: Akiko
authors.initials: A
authors.lastname: Koide
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
authors.forename: Tony
authors.initials: T
authors.lastname: Pawson
authors.affiliation: Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA. Electronic address: skoide@uchicago.edu.
authors.forename: Shohei
authors.initials: S
authors.lastname: Koide
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D002460:Cell Line; D018360:Crystallography, X-Ray; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000378:metabolism; D051519:Fibroblast Growth Factor 4 / Q000378:metabolism; D051380:GRB2 Adaptor Protein / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008958:Models, Molecular; D011485:Protein Binding / Q000235:genetics; D060066:Protein Interaction Maps / Q000235:genetics*; D017434:Protein Structure, Tertiary; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D015398:Signal Transduction / Q000235:genetics
chemical_list: C496446:Fgf4 protein, mouse; D051519:Fibroblast Growth Factor 4; D051380:GRB2 Adaptor Protein; C495949:Grb2 protein, mouse; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; C516725:Ptpn11 protein, mouse