PMID: 17020880 , Related PDB ids: 2J6K, 2J6O, 2J7I, 2JGF

Authors:

Moncalian G, Cardenes N, Deribe YL, Spinola-Amilibia M, Dikic I, Bravo J

Title:

Atypical polyproline recognition by the CMS N-terminal Src homology 3 domain.

Journal:

J Biol Chem. 2006 Dec 15;281(50):38845-53. Epub 2006 Oct 3.

Abstract:

The CIN85/CMS (human homologs of mouse SH3KBP1/CD2AP) family of endocytic adaptor proteins has the ability to engage multiple effectors and couple cargo trafficking with the cytoskeleton. CIN85 and CMS (Cas ligand with multiple Src homology 3 (SH3) domains) facilitate the formation of large multiprotein complexes required for an efficient internalization of cell surface receptors. It has recently been shown that c-Cbl/Cbl-b could mediate the formation of a ternary complex between one c-Cbl/Cbl-b molecule and two SH3 domains of CIN85, important for the ability of Cbl to promote epidermal growth factor receptor down-regulation. To further investigate whether multimerization is conserved within the family of adaptor proteins, we have solved the crystal structures of the CMS N-terminal SH3 domain-forming complexes with Cbl-b- and CD2-derived peptides. Together with biochemical evidence, the structures support the notion that, despite clear differences in the interaction surface, both Cbl-b and CD2 can mediate multimerization of N-terminal CMS SH3 domains. Detailed analyses on the interacting surfaces also provide the basis for a differential Cbl-b molecular recognition of CMS and CIN85.