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Updated: Oct 9, 2025

A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
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A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators

Published on: February 20, 2018

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G protein-coupled receptor interactions and modification of signalling involving the ghrelin receptor, GHSR1a

Mitchell Ty Ringuet1, John Barton Furness1,2, Sebastian George Barton Furness3

  • 1Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia.

Journal of Neuroendocrinology
|December 21, 2021
PubMed

Insights

The growth hormone secretagogue receptor 1a (GHSR1a) plays diverse roles beyond GH release, including neurogenesis and metabolism. Its interactions with other receptors reveal complex signaling pathways and physiological effects.

Area of Science:

  • Neuroendocrinology
  • Molecular Pharmacology
  • GPCR Signaling

Background:

  • The growth hormone secretagogue receptor 1a (GHSR1a) has known roles in growth hormone release and appetite regulation.
  • Emerging evidence implicates GHSR1a in neurogenesis, learning, memory, metabolism, and cardiovascular function.
  • Ghrelin, the endogenous GHSR1a agonist, is mainly gastric but influences the CNS via circulation.

Purpose of the Study:

  • To review the signaling mechanisms of GHSR1a.
  • To explore the physiological consequences of GHSR1a interactions with other G protein-coupled receptors (GPCRs).

Main Methods:

  • In vitro and in vivo studies were analyzed.
  • Literature review of GHSR1a signaling and heterodimerization with other GPCRs.

Main Results:

  • GHSR1a activation typically involves Gαq/11 pathways.
  • GHSR1a forms heterodimers with various GPCRs (e.g., dopamine, serotonin, orexin, oxytocin, MCR3) and MRAP2.
  • Receptor interactions modulate downstream signaling and agonist responses.

Conclusions:

  • GHSR1a exhibits complex signaling through homo- and heterodimerization.
  • These interactions contribute to the receptor's wide-ranging physiological effects.
  • Understanding these mechanisms is crucial for therapeutic targeting.
Keywords:
G protein-coupled receptorGHSR1aGPCRdimerisationghrelinghrelin receptor

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