Evidence for a physical association between the Shc-PTB domain and the beta c chain of the granulocyte-macrophage colony-stimulating factor receptor

J Biol Chem. 1996 May 24;271(21):12137-40. doi: 10.1074/jbc.271.21.12137.

Abstract

Granulocyte-macrophage colony-stimulating factor (GM-CSF) regulates the growth and function of several myeloid cell types at different stages of maturation. The effects of GM-CSF are mediated through a high affinity receptor that is composed of two chains: a unique, ligand-specific alpha chain and a beta common chain (beta c) that is also a component of the receptors for interleukin 3 (IL-3) and IL-5. Beta c plays an essential role in the transduction of extra cellular signals to the nucleus through its recruitment of secondary messengers. Several downstream signaling events induced by GM-CSF stimulation have been described, including activation of tyrosine kinases and tyrosine phosphorylation of cellular proteins (including beta c) and activation of the Ras/mitogen-activated protein kinase and the JAK/STAT pathways. A region within the beta c cytoplasmic tail (amino acids 517-763) has been reported to be necessary for tyrosine phosphorylation of the adapter protein, Shc, and for the subsequent GM-CSF-induced activation of Ras. In this paper, we describe a physical association between the tyrosine phosphorylated GM-CSF receptor (GMR)-beta c chain and Shc in vivo. Using a series of cytoplasmic truncation mutants of beta c and various mutant Shc proteins, we demonstrate that the N-terminal phosphotyrosine-binding (PTB) domain of Shc binds to a short region of beta c (amino acids 549-656) that contains Tyr577. Addition of a specific phosphopeptide encoding amino acids surrounding this tyrosine inhibited the interaction between beta c and shc. Moreover, mutation of a key residue within the phosphotyrosine binding pocket of the Shc-PTB domain abrogated its association with beta c. These observations provide an explanation for the previously described requirement for Tyr577 of beta c for GM-CSF-induced tyrosine phosphorylation of Shc and have implications for Ras activation through the GM-CSF, IL-3, and IL-5 receptors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adaptor Proteins, Signal Transducing*
  • Amino Acid Sequence
  • Animals
  • Cell Line
  • GRB2 Adaptor Protein
  • Janus Kinase 2
  • Molecular Sequence Data
  • Phenylalanine / genetics
  • Phosphorylation
  • Point Mutation
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism
  • Proteins / metabolism
  • Proto-Oncogene Proteins*
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / genetics
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / metabolism*
  • Signal Transduction
  • Tyrosine / genetics
  • Tyrosine / metabolism
  • src Homology Domains*

Substances

  • Adaptor Proteins, Signal Transducing
  • GRB2 Adaptor Protein
  • Proteins
  • Proto-Oncogene Proteins
  • Receptors, Granulocyte-Macrophage Colony-Stimulating Factor
  • Tyrosine
  • Phenylalanine
  • Protein-Tyrosine Kinases
  • Janus Kinase 2