Phosphotyrosine-dependent interaction of SHC and insulin receptor substrate 1 with the NPEY motif of the insulin receptor via a novel non-SH2 domain

Mol Cell Biol. 1995 May;15(5):2500-8. doi: 10.1128/MCB.15.5.2500.

Abstract

The SHC proteins have been implicated in insulin receptor (IR) signaling. In this study, we used the sensitive two-hybrid assay of protein-protein interaction to demonstrate that SHC interacts directly with the IR. The interaction is mediated by SHC amino acids 1 to 238 and is therefore independent of the Src homology 2 domain. The interaction is dependent upon IR autophosphorylation, since the interaction is eliminated by mutation of the IR ATP-binding site. In addition, mutational analysis of the Asn-Pro-Glu-Tyr (NPEY) motif within the juxtamembrane domain of the IR showed the importance of the Asn, Pro, and Tyr residues to both SHC and IR substrate 1 (IRS-1) binding. We conclude that SHC interacts directly with the IR and that phosphorylation of Tyr-960 within the IR juxtamembrane domain is necessary for efficient interaction. This interaction is highly reminiscent of that of IRS-1 with the IR, and we show that the SHC IR-binding domain can substitute for that of IRS-1 in yeast and COS cells. We identify a homologous region within the IR-binding domains of SHC and IRS-1, which we term the SAIN (SHC and IRS-1 NPXY-binding) domain, which may explain the basis of these interactions. The SAIN domain appears to represent a novel motif which is able to interact with autophosphorylated receptors such as the IR.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites / genetics
  • Cell Line
  • Cloning, Molecular
  • Humans
  • Insulin Receptor Substrate Proteins
  • Models, Biological
  • Molecular Sequence Data
  • Mutagenesis, Site-Directed
  • Phosphoproteins / metabolism*
  • Phosphotyrosine
  • Proteins / genetics
  • Proteins / metabolism*
  • Receptor, Insulin / genetics*
  • Receptor, Insulin / metabolism*
  • Saccharomyces cerevisiae / genetics
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • Tyrosine / analogs & derivatives*
  • Tyrosine / metabolism

Substances

  • IRS1 protein, human
  • Insulin Receptor Substrate Proteins
  • Phosphoproteins
  • Proteins
  • Phosphotyrosine
  • Tyrosine
  • Receptor, Insulin