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Updated: Jul 10, 2025
07:10
Taste Exam: A Brief and Validated Test
Published on: August 17, 2018
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Cardiac human bitter taste receptors contain naturally occurring variants that alter function
Conor J Bloxham1, Katina D Hulme2, Fabrizio Fierro3
1School of Biomedical Sciences, Faculty of Medicine, University of Queensland, QLD, Australia; Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, Germany.
Biochemical Pharmacology
|November 21, 2023
Summary
Bitter taste receptors (T2Rs) in the heart vary due to genetic differences, impacting cardiovascular function. Understanding these T2R polymorphisms is key to exploring their role in heart health.
Area of Science:
- Pharmacology
- Genetics
- Cardiovascular Physiology
Background:
- Bitter taste receptors (T2Rs) are G protein-coupled receptors involved in detecting toxins.
- T2Rs are expressed in non-gustatory tissues, including the human heart, suggesting roles beyond taste.
- Individual differences in bitter perception are linked to T2R gene variations (polymorphisms).
Purpose of the Study:
- To functionally characterize T2Rs (10, 14, 30, 31, 46, 50) found in human cardiac tissue.
- To investigate the impact of naturally occurring T2R polymorphisms on receptor signaling.
- To explore the potential role of cardiac T2R variants in cardiovascular physiology.
Main Methods:
- Functional characterization of T2R variants identified in human cardiac tissue.
- Assessment of ligand-dependent signaling responses and G protein coupling (Gαi) using a cAMP biosensor.
- Molecular modeling to analyze the structural impact of T2R polymorphisms on ligand binding and protein interactions.
Main Results:
- Specific T2R variants (T2R30 Leu252, T2R46 Met228) exhibited abolished ligand-dependent signaling.
- Other variants showed altered maximal responses but not potency.
- T2R14 Phe201 variant failed to productively couple to Gαi, unlike wild-type T2R14.
- T2R50 Tyr203 (rs1376251) showed signaling differences and is associated with cardiovascular disease.
Conclusions:
- Naturally occurring functional variations exist in cardiac-expressed T2Rs.
- These T2R polymorphisms affect ligand binding and Gα protein interactions.
- Findings highlight the importance of studying T2R variants in the cardiovascular system, particularly T2R50.
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