Nucleic acids encoding T2R taste receptors
View Patent ↗The invention provides nucleic acid and amino acid sequences for a novel family of taste transduction G-protein coupled receptors, antibodies to such receptors, methods of detecting such nucleic acids and receptors, and methods of screening for modulators of taste transduction G-protein coupled receptors.
1. An isolated nucleic acid encoding a taste transduction G protein-coupled receptor having G protein-coupled receptor activity, the receptor comprising a polypeptide with greater than 90% amino acid sequence identity to SEQ ID NO:15, wherein said receptor detects bitter tastants.
2. The nucleic acid of claim 1 , wherein the polypeptide sequence is SEQ ID NO:15.
3. The nucleic acid of claim 1 , wherein the polypeptide has greater than 95% amino acid sequence identity to SEQ ID NO:15.
4. An isolated expression vector comprising the nucleic acid of claim 1 .
5. An isolated cell comprising the expression vector of claim 4 .
6. A method for identifying a compound that modulates taste signaling in taste cells, the method comprising the steps of:
(i) contacting the taste transduction G protein-coupled receptor polypeptide encoded by the nucleic acid of claim 1 in a cell with the compound; and
(ii) determining the functional effect of the compound upon the polypeptide, thereby identifying a compound that modulates taste signaling in taste cells.
7. The method of claim 6 , wherein the functional effect is determined by measuring binding of the compound to an extracellular domain or a transmembrane region of the polypeptide.
8. The method of claim 6 , wherein the functional effect is determined by measuring binding of radiolabeled GTP to the polypeptide.
9. The method of claim 6 , wherein the polypeptide is recombinant.
10. The method of claim 6 , wherein the functional effect is measured by determining changes in the electrical activity in the cell expressing the polypeptide.
11. The method of claim 6 , wherein the functional effect is determined by measuring changes in intracellular cAMP, cGMP, IP3, or Ca 2+ .
12. The method of claim 6 , wherein the cell is an HEK-293 cell.
13. The method of claim 6 , wherein the polypeptide is a fusion protein comprising at least about 20 consecutive N-terminal amino acids of a rhodopsin protein.
14. The method of claim 6 , wherein the cell comprises Gα15.
15. The method of claim 6 , wherein the polypeptide is contacted with the compound in the presence of a bitter tastant, and wherein a difference in the functional effect of the bitter tastant on the cell in the presence of the compound and the functional effect of the bitter tastant on the cell in the absence of the compound indicates that the compound is capable of modulating taste signaling in taste cells.
16. The method of claim 6 , wherein the polypeptide is covalently linked to a heterologous polypeptide, forming a chimeric polypeptide.
17. The method of claim 6 , wherein the polypeptide is linked to a solid phase.
18. The method of claim 6 , wherein said polypeptide comprises a sequence with at least 95% identity to SEQ ID NO:15.