Crystal structure of the hCASK PDZ domain reveals the structural basis of class II PDZ domain target recognitionDaniels, D.L., Cohen, A.R., Anderson, J.M., Brunger, A.T.
(1998) Nat Struct Biol 5: 317-325
- PubMed: 9546224
- DOI: https://doi.org/10.1038/nsb0498-317
- Primary Citation of Related Structures:
- PubMed Abstract:
PDZ domain containing proteins assist formation of cell-cell junctions and localization of membrane protein receptors and ion channels. PDZ domains interact with the C-terminal residues of a particular target membrane protein. Based on their binding specificities and sequence homologies, PDZ domains fall into two classes. The first crystal structure of a class II PDZ domain, that of hCASK, has been solved by multi-wavelength anomalous dispersion phasing. Complex formation with the C-terminus of a neighboring non-crystallographically related PDZ domain reveals interactions between hCASK and its ligand. Class II PDZ domains differ from class I domains by formation of a second hydrophobic binding pocket. The C-terminal carboxylate binding loop of the PDZ domain is structurally conserved in both classes suggesting a generalized carboxylate binding motif (h-Gly-h) where h is a hydrophobic residue.
The Howard Hughes Medical Institute and Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520, USA.