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1x8s
From Proteopedia
Structure of the Par-6 PDZ domain with a Pals1 internal ligand
Overview
PDZ protein interaction domains are typically selective for C-terminal ligands, but non-C-terminal, 'internal' ligands have also been identified. The PDZ domain from the cell polarity protein Par-6 binds C-terminal ligands and an internal sequence from the protein Pals1/Stardust. The structure of the Pals1-Par-6 PDZ complex reveals that the PDZ ligand-binding site is deformed to allow for internal binding. Whereas binding of the Rho GTPase Cdc42 to a CRIB domain adjacent to the Par-6 PDZ regulates binding of C-terminal ligands, the conformational change that occurs upon binding of Pals1 renders its binding independent of Cdc42. These results suggest a mechanism by which the requirement for a C terminus can be readily bypassed by PDZ ligands and reveal a complex set of cooperative and competitive interactions in Par-6 that are likely to be important for cell polarity regulation.
About this Structure
1X8S is a Single protein structure of sequence from Drosophila melanogaster. Full crystallographic information is available from OCA.
Reference
Internal recognition through PDZ domain plasticity in the Par-6-Pals1 complex., Penkert RR, DiVittorio HM, Prehoda KE, Nat Struct Mol Biol. 2004 Nov;11(11):1122-7. Epub 2004 Oct 10. PMID:15475968 Page seeded by OCA on Sat May 3 14:42:47 2008
