Download MendeleyHigh Resolution Crystal Structure of the Grb2 SH2 Domain with a Phosphopeptide Derived from CD28
Higo, K., Ikura, T., Oda, M., Morii, H., Takahashi, J., Abe, R., Ito, N.(2013) PLoS One 8: e74482-e74482
- PubMed: 24098653
- DOI: https://doi.org/10.1371/journal.pone.0074482
- Primary Citation of Related Structures:
3WA4 - PubMed Abstract:
Src homology 2 (SH2) domains play a critical role in cellular signal transduction. They bind to peptides containing phosphotyrosine (pY) with various specificities that depend on the flanking amino-acid residues. The SH2 domain of growth-factor receptor-bound protein 2 (Grb2) specifically recognizes pY-X-N-X, whereas the SH2 domains in phosphatidylinositol 3-kinase (PI3K) recognize pY-X-X-M. Binding of the pY site in CD28 (pY-M-N-M) by PI3K and Grb2 through their SH2 domains is a key step that triggers the CD28 signal transduction for T cell activation and differentiation. In this study, we determined the crystal structure of the Grb2 SH2 domain in complex with a pY-containing peptide derived from CD28 at 1.35 Å resolution. The peptide was found to adopt a twisted U-type conformation, similar to, but distinct from type-I β-turn. In all previously reported crystal structures, the peptide bound to the Grb2 SH2 domains adopts a type-I β-turn conformation, except those with a proline residue at the pY+3 position. Molecular modeling also suggests that the same peptide bound to PI3K might adopt a very different conformation.
Organizational Affiliation:
Research Institute for Biomedical Sciences, Tokyo University of Science, Noda-shi, Chiba, Japan.
