Molecular recognition properties of the C-terminal Sh3 domain of the Cbl associated protein, Cap.
A phage-displayed combinatorial peptide library was used to define the specificity of one of the three Src homology 3 (SH3) domains in a novel cytoskeletal protein, named CAP, for Cbl Associated Protein. The C-terminal SH3 domain was used to affinity select peptides with the consensus, PXPPXRXSSL, from a library of X6PXXPX6 peptides. Peptide sequences resembling this consensus were identified in two signal transduction proteins, c-Cbl and son-on-sevenless (Sos), previously shown to interact with the C-terminal SH3 domain of CAP. Genetic fusion of 16 and 14 amino acid segments of c-Cbl and Sos, respectively, to bacterial alkaline phosphatase confirmed that these segments were potential ligand sites for the C-terminal SH3 domain of CAP. Alanine-scanning mutagenesis of the c-Cbl peptide ligand confirmed that most of the residues, which were conserved among the peptide ligands selected from the combinatorial peptide library, contributed to binding to the C-terminal SH3 domain of CAP.
Kurakin
A
A
Department of Pharmacology, University of Wisconsin-Madison, USA.
Hoffman
N G
NG
Kay
B K
BK
D000595:Amino Acid Sequence; D000818:Animals; D003598:Cytoskeletal Proteins / Q000737:chemistry* / Q000378:metabolism; D004330:Drosophila; D008969:Molecular Sequence Data; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D050721:Proto-Oncogene Proteins c-cbl; D044767:Ubiquitin-Protein Ligases; D018909:src Homology Domains
D003598:Cytoskeletal Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D050721:Proto-Oncogene Proteins c-cbl; D044767:Ubiquitin-Protein Ligases