Thermodynamic Studies of SHC Phosphotyrosine Interaction Domain Recognition of the NPXpY Motif
| Autor: | Valsan Mandiyan, Min Zhou, Julian M. Sturtevant, Joseph Schlessinger, Ben Margolis, Ronan O'Brien, Mark A. Lemmon |
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| Rok vydání: | 1996 |
| Předmět: |
Stereochemistry
Recombinant Fusion Proteins Molecular Sequence Data Peptide Peptide binding Calorimetry SH2 domain Biochemistry src Homology Domains Pi Point Mutation Amino Acid Sequence Epidermal growth factor receptor Phosphotyrosine Molecular Biology Adaptor Proteins Signal Transducing Glutathione Transferase chemistry.chemical_classification Binding Sites biology Chemistry Proteins Isothermal titration calorimetry Cell Biology Peptide Fragments Amino acid ErbB Receptors Adaptor Proteins Vesicular Transport Shc Signaling Adaptor Proteins Protein Biosynthesis Trk receptor Mutagenesis Site-Directed biology.protein Thermodynamics |
| Zdroj: | Journal of Biological Chemistry. 271:4770-4775 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.271.9.4770 |
| Popis: | The N-terminal 200 amino acids of SHC constitute a unique phosphotyrosine (Tyr(P)) interaction (PI) domain that shows no significant sequence similarity to the other Tyr(P)-recognizing module, the SH2 domain. We describe the thermodynamic parameters characterizing PI domain binding to various tyrosyl phosphopeptides, using isothermal titration calorimetry. The PI domain forms 1:1 complexes of similar affinity with a 12-mer peptide (ISLDNPDpYQQDF) derived from Tyr-1148 of the epidermal growth factor receptor (EGFR) (KD = 28 nm) and an 18-mer (LQGHIIENPQpYFSDACVH) derived from Tyr-490 of Trk (KD = 42 nM). Binding of the EGFR-derived peptide was largely enthalpy-driven at 25 degrees C, while Trk490 peptide binding was entropy-driven. Based on the change in heat capacity upon binding, approximately 700 A2 of nonpolar surface was estimated to be buried upon interaction. Alteration of the Asn or Pro to Ala in the NPXpY motif of the EGFR Tyr-1148 peptide increased the KD of PI domain interactions to 238 and 370 nM, respectively. Alteration of a Leu at position -5 (with respect to Tyr(P)) in the EGFR peptide to Gly also reduced the binding affinity (KD = 580 nM). It is proposed that the PI domain recognizes the beta1 turn that is found in NPXpY-containing peptides and also interacts with a larger segment of the peptide than seen for SH2 domains. |
| Databáze: | OpenAIRE |
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