p105CasL (CasL) is a recently identified signaling molecule closely related to the p130Cas (Crk-associated substrate) docking protein. CasL has a single Src homology (SH) 3 domain in its N-terminal portion followed by multiple consensus motifs for binding to SH2 domains. Like original p130Cas, CasL
Molecular basis for regulation of Src by the docking protein p130Cas
✍ Scribed by Fariborz Nasertorabi; Kaspars Tars; Kathleen Becherer; Ramadurgam Kodandapani; Lars Liljas; Kristiina Vuori; Kathryn R. Ely
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 247 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0952-3499
- DOI
- 10.1002/jmr.755
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The docking protein p130Cas (Cas) becomes tyrosine‐phosphorylated in its central substrate domain in response to extracellular stimuli such as integrin‐mediated cell adhesion, and transmits signals through interactions with various intracellular signaling molecules such as the adaptor protein Crk. Src‐family kinases (SFKs) bind a specific site in the carboxyl‐terminal region of Cas and subsequently SFKs phosphorylate progressively the substrate domain in Cas. In this study crystallography, mutagenesis and binding assays were used to understand the molecular basis for Cas interactions with SFKs. Tyrosine phosphorylation regulates binding of Cas to SFKs, and the primary site for this phosphorylation, Y762, has been proposed. A phosphorylated peptide corresponding to Cas residues ^759^MEDpYDYVHL^767^ containing the key phosphotyrosine was crystallized in complex with the SH3–SH2 domain of the SFK Lck. The results provide the first structural data for this protein–protein interaction. The motif in Cas ^762^pYDYV binds to the SH2 domain in a mode that mimics high‐affinity ligands, involving dual contacts of Y762 and V765 with conserved residues in SFK SH2 domains. In addition, Y764 is in position to make an electrostatic contact after phosphorylation with a conserved SFK arginine that mediates interactions with other high‐affinity SH2 binders. These new molecular data suggest that Cas may regulate activity of Src as a competing ligand to displace intramolecular interactions that occur in SFKs (between the C‐terminal tail and the SH2 domain) and restrain and down‐regulate the kinase in an inactive form. Copyright © 2005 John Wiley & Sons, Ltd.
📜 SIMILAR VOLUMES
Conformational searches on three closely related pp60 c-src protein tyrosine kinase inhibitors of varying potencies were performed to determine a structural basis for their activity. The first was a linear peptide (PDNEYAFFQf), the second its 10-membered cyclic analogue, and the third a cyclic analo
## Abstract The homology modeling technique has been used to construct the structure of enterovirus 71 (EV 71) capsid protein VP1. The protein is consisted of 297 amino acid residues and treated as the target. The amino acid sequence identity between the target protein and sequences of template pro