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A BW Reporter System for Studying Receptor-Ligand Interactions
Published on: January 7, 2019
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Multivalent ligands for the serotonin 5-HT4 receptor.
Federica Castriconi1, Marco Paolino1, Alessandro Donati1
1Dipartimento di Biotecnologie , Chimica e Farmacia and European Research Centre for Drug Discovery and Development , Università degli Studi di Siena , Via A. Moro 2 , 53100 Siena , Italy . Email: andrea.cappelli@unisi.it ; ; Tel: +39 0577 234320.
Medchemcomm
|August 16, 2018
Summary
Multivalent ligands targeting serotonin 5-HT4 receptors showed increased binding affinity but not enhanced efficacy. This suggests receptor dimerization does not benefit from multivalency for this specific partial agonist.
Area of Science:
- Pharmacology
- Molecular Biology
- Biochemistry
Background:
- Constitutive dimerization of serotonin 5-HT4 receptors in cell membranes is established.
- Investigating multivalency's impact on ligand interactions and efficacy is crucial for drug development.
Purpose of the Study:
- To determine if multivalent ligands can enhance binding affinity and/or efficacy at serotonin 5-HT4 receptors.
- To explore the role of ligand multivalency in the context of constitutive receptor dimerization.
Main Methods:
- Synthesis of bivalent and tetravalent ligands by modifying ML10302 with oligo(ethylene glycol) chains.
- Assessment of binding affinity using appropriate controls.
- Evaluation of receptor-G protein interaction and cAMP signaling pathways.
Main Results:
- Bivalent and tetravalent ligands exhibited a 10-20 fold increase in binding affinity compared to monovalent controls.
- No multivalent ligand surpassed the binding energy of the parent compound, ML10302.
- Multivalency did not enhance the efficacy of ML10302 in receptor-Gs interaction or cAMP signaling.
Conclusions:
- While multivalency can increase binding affinity for serotonin 5-HT4 receptors, it does not improve efficacy for the partial agonist ML10302.
- Constitutive receptor dimerization may not be effectively leveraged by simple multivalent ligand designs to boost signaling.
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