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Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
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Gαi-derived peptide binds the µ-opioid receptor.
Piotr Kossoń1, Jolanta Dyniewicz1, Piotr F J Lipiński1
1Department of Neuropeptides, Mossakowski Medical Research Centre Polish Academy of Sciences, Pawinskiego 5, 02-106, Warsaw, Poland.
Pharmacological Reports : PR
|February 25, 2023
Summary
A Gαi-derived peptide acts as an allosteric modulator for the µ-opioid receptor (µOR), enhancing agonist affinity. This finding extends GPCR-G protein interactions beyond rhodopsin and suggests therapeutic potential.
Area of Science:
- Biochemistry
- Molecular Pharmacology
- Structural Biology
Background:
- G protein-coupled receptors (GPCRs) mediate cellular responses through G protein interactions.
- GPCR-G protein binding involves specific domains of the Gα subunit.
- Previous studies indicated G protein C-terminal peptides stabilize active receptors like rhodopsin.
Purpose of the Study:
- To investigate the interaction between a Gαi-derived peptide and the µ-opioid receptor (µOR).
- To determine if this peptide acts as an allosteric modulator of µOR.
- To explore the potential for GPCR-G protein interface modulation via peptides.
Main Methods:
- Utilized Molecular Dynamics simulations.
- Performed biological evaluation using radio-ligand binding assays.
- Studied interactions between a Gαi-derived peptide (G-peptide) and µOR.
Main Results:
- A 12-amino acid Gαi-derived peptide binds to the µ-opioid receptor.
- The peptide functions as an allosteric modulator, increasing µOR affinity for morphine in a dose-dependent manner.
- Demonstrated that the Gαi C-terminal peptide stabilizes the active conformation of µOR.
Conclusions:
- GPCR-Gα peptide interactions are not limited to rhodopsin and can be extrapolated to µOR.
- The C-terminal peptide of Gαi is sufficient to stabilize the active state of the µOR.
- This research opens avenues for investigating and modifying the GPCR-G protein interface using peptide-based strategies.
Keywords:
Functional assayG protein couplingG protein-coupled receptorsGPCRMolecular dynamics simulationµ-opioid receptorMore Related Videos
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