Multimeric and differential binding of CIN85/CD2AP with two atypical proline-rich sequences from CD2 and Cbl-b*.

TitleMultimeric and differential binding of CIN85/CD2AP with two atypical proline-rich sequences from CD2 and Cbl-b*.
Publication TypeJournal Article
Year of Publication2013
AuthorsCeregido Pérez, M de los Á., A. Garcia-Pino, J. L. Ortega-Roldan, S. Casares, O. López Mayorga, J. Bravo, N. A. J. van Nuland, and A. I. Azuaga
JournalFEBS J
Volume280
Issue14
Pagination3399-415
Date Published2013 Jul
ISSN1742-4658
KeywordsAdaptor Proteins, Signal Transducing, Amino Acid Sequence, Antigens, CD2, Cytoskeletal Proteins, Humans, Hydrogen Bonding, Models, Molecular, Molecular Sequence Data, Nuclear Magnetic Resonance, Biomolecular, Proline, Protein Binding, Protein Structure, Secondary, Proto-Oncogene Proteins c-cbl, Scattering, Small Angle, src Homology Domains, Thermodynamics, Titrimetry, X-Ray Diffraction
Abstract

The CD2AP (CD2-associated protein) and CIN85 (Cbl-interacting protein of 85 kDa) adaptor proteins each employ three Src homology 3 (SH3) domains to cluster protein partners and ensure efficient signal transduction and down-regulation of tyrosine kinase receptors. Using NMR, isothermal titration calorimetry and small-angle X-ray scattering methods, we have characterized several binding modes of the N-terminal SH3 domain (SH3A) of CD2AP and CIN85 with two natural atypical proline-rich regions in CD2 (cluster of differentiation 2) and Cbl-b (Casitas B-lineage lymphoma), and compared these data with previous studies and published crystal structures. Our experiments show that the CD2AP-SH3A domain forms a type II dimer with CD2 and both type I and type II dimeric complexes with Cbl-b. Like CD2AP, the CIN85-SH3A domain forms a type II complex with CD2, but a trimeric complex with Cbl-b, whereby the type I and II interactions take place at the same time. Together, these results explain how multiple interactions among similar SH3 domains and ligands produce a high degree of diversity in tyrosine kinase, cell adhesion or T-cell signaling pathways.

DOI10.1111/febs.12333
Alternate JournalFEBS J.
PubMed ID23663663