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Updated: Jul 16, 2026
10:13
Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
Purine and pyrimidine receptors
1Autonomic Neuroscience Centre, Royal Free and University College Medical School, London, UK. g.burnstock@ucl.ac.uk
Cellular and Molecular Life Sciences : CMLS
|March 22, 2007
Summary
Adenosine 5'-triphosphate (ATP) and its breakdown product adenosine act as extracellular signals through P1 and P2 receptors. These receptors, including P2X ion channels and P2Y G protein-coupled receptors, have diverse subtypes and functions.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Signaling
Background:
- Adenosine 5 -triphosphate (ATP) functions intracellularly and as an extracellular signaling molecule.
- Extracellular ATP is degraded by ectonucleotidases into adenosine.
- Purinergic signaling involves P1 receptors (adenosine-selective) and P2 receptors (purine/pyrimidine-activated).
Purpose of the Study:
- To review the cloned and characterized subtypes of P1 and P2 receptors.
- To describe the molecular nature and subtypes of P1 and P2 receptors.
Main Methods:
- Literature review of cloned and characterized P1 and P2 receptor subtypes.
- Summary of known P2X (ligand-gated ion channels) and P2Y (G protein-coupled) receptor structures and functions.
Main Results:
- Four subtypes of P1 receptors (A(1), A(2A), A(2B), A(3)) selective for adenosine have been identified.
- Seven subunits of P2X receptors form homomultimers and heteromultimers.
- Eight subtypes of P2Y receptors have been cloned and characterized.
Conclusions:
- P1 and P2 receptors represent a complex system for extracellular purinergic and pyrimidinergic signaling.
- The diverse subtypes of P2X and P2Y receptors suggest varied roles in physiological and pathological processes.
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