6HEP image
Entry Detail
PDB ID:
6HEP
Title:
Crystal structure of human 14-3-3 beta in complex with CFTR R-domain peptide pS753-pS768
Biological Source:
Source Organism:
PDB Version:
Deposition Date:
2018-08-20
Release Date:
2018-10-24
Method Details:
Experimental Method:
Resolution:
1.86 Å
R-Value Free:
0.25
R-Value Work:
0.20
R-Value Observed:
0.20
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:14-3-3 protein beta/alpha
Chain IDs:A, B, C, D
Chain Length:235
Number of Molecules:4
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Cystic fibrosis transmembrane conductance regulator
Chain IDs:E, F
Chain Length:28
Number of Molecules:2
Biological Source:Homo sapiens
Modified Residue
Compound ID Chain ID Parent Comp ID Details 2D Image
SEP E SER modified residue
Ligand Molecules
Primary Citation
A Thermodynamic Model for Multivalency in 14-3-3 Protein-Protein Interactions.
J. Am. Chem. Soc. 140 14498 14510 (2018)
PMID: 30296824 DOI: 10.1021/jacs.8b09618

Abstact

Protein-protein interactions (PPIs) are at the core of molecular control over cellular function. Multivalency in PPI formation, such as via proteins with multiple binding sites and different valencies, requires fundamental understanding to address correlated challenges in pathologies and drug development. Thermodynamic binding models are needed to provide frameworks for describing multivalent PPIs. We established a model based on ditopic host-guest systems featuring the effective molarity, a hallmark property of multivalency, as a prime parameter governing the intramolecular binding in divalent interactions. By way of illustration, we study the interaction of the bivalent 14-3-3 protein scaffold with both the nonavalent CFTR and the hexavalent LRRK2 proteins, determining the underlying thermodynamics and providing insights into the role of individual sites in the context of the multivalent platform. Fitting of binding data reveals enthalpy-entropy correlation in both systems. Simulations of speciations for the entire phosphorylated protein domains reveal that the CFTR protein preferably binds to 14-3-3 by combinations including the strongest binding site pS768, but that other binding sites take over when this site is eliminated, leading to only a minor decrease in total affinity for 14-3-3. For LRRK2, two binding sites dominate the complex formation with 14-3-3, but the distantly located pS1444 site also plays a role in complex formation. Thermodynamic modeling of these multivalent PPIs allowed analyzing and predicting the effects of individual sites regarding their modulation via, for example, (de)phosphorylation or small-molecule targeting. The results specifically bring forward the potential of PPI stabilization, as an entry for drug discovery for multivalent PPIs.

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Primary Citation of related structures