Skip to Main content Skip to Navigation
Journal articles

Interactions outside the boundaries of the canonical binding groove of a PDZ domain influence ligand binding.

Abstract : The postsynaptic density protein-95/discs large/zonula occludens-1 (PDZ) domain is a protein-protein interaction module with a shallow binding groove where protein ligands bind. However, interactions that are not part of this canonical binding groove are likely to modulate peptide binding. We have investigated such interactions beyond the binding groove for PDZ3 from PSD-95 and a peptide derived from the C-terminus of the natural ligand CRIPT. We found via nuclear magnetic resonance experiments that up to eight residues of the peptide ligand interact with the PDZ domain, showing that the interaction surface extends far outside of the binding groove as defined by the crystal structure. PDZ3 contains an extra structural element, a C-terminal helix (α3), which is known to affect affinity. Deletion of this helix resulted in the loss of several intermolecular nuclear Overhauser enhancements from peptide residues outside of the binding pocket, suggesting that α3 forms part of the extra binding surface in wild-type PDZ3. Site-directed mutagenesis, isothermal titration calorimetry, and fluorescence intensity experiments confirmed the importance of both α3 and the N-terminal part of the peptide for the affinity. Our data suggest a general mechanism in which different binding surfaces outside of the PDZ binding groove could provide sites for specific interactions.
Document type :
Journal articles
Complete list of metadatas

Cited literature [5 references]  Display  Hide  Download

https://hal-riip.archives-ouvertes.fr/pasteur-00974713
Contributor : Istituto Pasteur Fondazione Cenci Bolognetti <>
Submitted on : Monday, April 7, 2014 - 1:24:48 PM
Last modification on : Wednesday, October 28, 2020 - 3:20:07 PM
Long-term archiving on: : Monday, April 10, 2017 - 10:29:21 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : jamais

Please log in to resquest access to the document

Identifiers

Collections

Citation

Celestine N Chi, S Raza Haq, Serena Rinaldo, Jakob Dogan, Francesca Cutruzzolà, et al.. Interactions outside the boundaries of the canonical binding groove of a PDZ domain influence ligand binding.. Biochemistry, American Chemical Society, 2012, 51 (44), pp.8971-9. ⟨10.1021/bi300792h⟩. ⟨pasteur-00974713⟩

Share

Metrics

Record views

155