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An amino-acid taste receptor
Greg Nelson1, Jayaram Chandrashekar, Mark A Hoon
1Howard Hughes Medical Institute and Departments of Biology and Neurosciences, University of California at San Diego, La Jolla, California, 92093-0649, USA.
Nature
|March 15, 2002
Summary
Scientists discovered a new mammalian taste receptor, T1R1+3, responsible for detecting L-amino acids, which are essential for protein building. This finding sheds light on the evolution of taste perception for vital nutrients.
Area of Science:
- Sensory biology
- Molecular biology
- Evolutionary biology
Background:
- The sense of taste is crucial for identifying food quality and detecting toxins.
- Amino acids, essential for protein synthesis and metabolism, elicit taste responses in mammals.
- A dedicated taste pathway for amino acids likely conferred evolutionary advantages.
Purpose of the Study:
- To identify and characterize the mammalian taste receptor responsible for amino acid detection.
- To understand the molecular mechanisms and evolutionary implications of amino acid taste perception.
Main Methods:
- Identification and characterization of mammalian amino acid taste receptors.
- Functional analysis of T1R1 and T1R3 G-protein-coupled receptors.
- Comparative analysis of T1R receptor sequences across species.
Main Results:
- The T1R1+3 heteromer functions as a broadly tuned L-amino acid sensor.
- The receptor responds to most standard L-amino acids but not their D-enantiomers.
- Sequence variations in T1R receptors influence taste response selectivity and specificity between species.
Conclusions:
- T1R1+3 is the primary mammalian receptor for detecting L-amino acids.
- This discovery deepens our understanding of taste perception and its evolutionary significance.
- Species-specific differences in T1R receptors contribute to variations in taste responses.
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