Sour/Acid Taste Receptors Assays, Genes and Proteins

Abstract

Taste receptor PC-1-L3/PC-2-L1 is provided. Methods and systems for screening for tastants and receptor modulators are provided. Knock out and transgenic animals, methods of detecting polymorphisms, and methods of correcting taste defects are also provided.

1 . A method of identifying a compound that binds to or modulates an activity of a polycystin 1-like 3 (PC-1-L3) taste receptor polypeptide, or a polycystin-2-like 1(PC-2-L1)/PC-1-L3 polypeptide complex, the method comprising:
 (a.) contacting a biological or biochemical sample comprising the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex with a test compound; and,   (b.) detecting binding of the test compound to the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex, or modulation of the activity of the polypeptide or polypeptide complex by the test compound, thereby identifying the compound that binds to or modulates the activity of the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex.   
   
   
       2 - 3 . (canceled) 
   
   
       4 . The method of  claim 1 , wherein (a.) comprises contacting one or more biological sample comprising one or more PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex with a plurality of test compounds and wherein (b.) comprises detecting binding of the test compounds to the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex, or modulation of the activity of the polypeptide by the test compounds, thereby identifying one or more compound that binds to or modulates the activity of the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex. 
   
   
       5 . The method of  claim 1 , wherein the polypeptide complex is a taste receptor polypeptide complex. 
   
   
       6 . The method of  claim 1 , wherein the PC-1-L3) taste receptor polypeptide, or a polycystin-2-like 1(PC-2-L1)/PC-1-L3 polypeptide complex is a component of an acid sensing, pH sensing, or sour tastant sensing receptor. 
   
   
       7 . (canceled) 
   
   
       8 . The method of  claim 1 , wherein the test compound is selected from the group consisting of: naturally occurring compounds, ions, sour tastants, small organic molecules, peptides, peptide mimetics, an acid, a weak acid, CO, CO 2 , acetic acid, a specific blocker of carbonic anhydrase, MK-417, an ion channel agonist, an ion channel antagonist, an ion channel enhancer, a non-specific Ca +  channel blocker, Nifedipine and structurally related compounds, Verapamil and structurally related compounds, gadolinium and structurally related compounds, and a stretch-induced channel blocker. 
   
   
       9 . The method of  claim 1 , wherein the test compound enhances an activity of the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex. 
   
   
       10 . The method of  claim 1 , wherein the test compound potentiates an activity of the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex. 
   
   
       11 . The method of  claim 1 , wherein the test compound inhibits or blocks an activity of the PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 polypeptide complex. 
   
   
       12 . The method of  claim 1 , wherein the PC-1-L3 taste receptor polypeptide is a human PC-1-L3 taste receptor polypeptide, or wherein the PC-2-L1/PC-1-L3 complex is a human PC-2-L1/PC-1-L3 polypeptide complex. 
   
   
       13 . The method of  claim 1 , wherein the PC-1-L3 taste receptor polypeptide is a murine PC-1-L3 taste receptor polypeptide or wherein the PC-2-L1/PC-1-L3 polypeptide complex is a murine PC-2-L1/PC-1-L3 complex. 
   
   
       14 . (canceled) 
   
   
       15 . The method of  claim 1 , wherein step (b.) includes detecting binding between the PC-1-L3 taste receptor polypeptide and a moiety selected from the group consisting of: a PC-2-L1 polypeptide, a potentiator of the PC-1-L3 taste receptor polypeptide, an antagonist of the PC-1-L3 taste receptor polypeptide, an agonist of the PC-1-L3 taste receptor polypeptide, an inverse agonist of the PC-1-L3 taste receptor polypeptide, a ligand that specifically binds to the PC-1-L3 taste receptor polypeptide, and an antibody that specifically binds to the PC-1-L3 taste receptor polypeptide. 
   
   
       16 . The method of  claim 1 , wherein step (b.) includes detecting binding between the PC-2-L1/PC-1-L3 polypeptide complex and a moiety selected from the group consisting of: a potentiator of the complex, an antagonist of the complex, an agonist of the complex, an inverse agonist of the complex, a ligand that specifically binds to the complex, and an antibody that specifically binds to the complex. 
   
   
       17 - 20 . (canceled) 
   
   
       21 . The method of  claim 1 , wherein detecting binding of the test compound to the PC-1-L3 taste receptor polypeptide or the PC-2-L1/PC-1-L3 polypeptide complex, or activity of the test compound on the PC-1-L3 taste receptor polypeptide or the PC-2-L1/PC-1-L3 polypeptide complex comprises detecting one or more of: detecting binding between PC-2-L1 and PC-1-L3, formation or stability of the polypeptide complex, H +  flux, Na +  flux, Ca 2+  flux, ion flux, changes in an activity of an intracellular pH or ion sensor, depolarization of the cell, cell membrane voltage changes, cell membrane conductivity changes, a kinase activity triggered upon binding of a compound to the PC-1-L3 taste receptor polypeptide, generation, breakdown or binding of a phorbol ester by the PC-1-L3 taste receptor polypeptide, binding of diacylglycerol or other lipids by the PC-1-L3 taste receptor polypeptide, cAMP activity, cGMP activity, GTPgammaS binding, phospholipase C activity, activity of an enzyme involved in cellular ionic balance, binding of PC-1-L3 to another PKD protein, or a transcriptional reporter activity. 
   
   
       22 . The method of  claim 1 , further comprising recombinantly expressing a PKD1-L3 gene in a recombinant cell, or both a PKD1-L3 gene and a PKD2L1 gene in a recombinant cell, wherein the biological sample is derived from the recombinant cell. 
   
   
       23 . The method of  claim 22 , wherein the PKD1-L3 gene, or the PKD1-L3 and the PKD2L1 gene is or are heterologous to the recombinant cell. 
   
   
       24 - 25 . (canceled) 
   
   
       26 . The method of  claim 1 , wherein the PC-1-L3 taste receptor polypeptide or the PC-2-L1/PC-1-L3 complex is incorporated into a biosensor. 
   
   
       27 - 35 . (canceled) 
   
   
       36 . A method of detecting a taste-induced behavior or physiological response modulated by a PC-1-L3 taste receptor polypeptide or PC-2-L1/PC-1-L3 taste receptor polypeptide complex, the method comprising:
 (a) introducing a heterologous PKD1-L3 taste receptor gene into an animal and expressing an encoded heterologous PC-1-L3 taste receptor polypeptide in a taste bud of the animal;   (b) providing a putative taste receptor tastant or modulator to the animal; and,   (c) monitoring a feeding behavior or physiological response of the animal in response to the presence of the putative taste receptor tastant or modulator.   
   
   
       37 - 52 . (canceled) 
   
   
       53 . A method of modulating an activity of a cell expressing a PC-2L1/PC-1L3 polypeptide complex, the method comprising contacting the cell with a compound that binds to or modulates an activity of the complex. 
   
   
       54 - 56 . (canceled) 
   
   
       57 . A recombinant cell comprising a heterologous PKD1-L3 gene and a heterologous PKD2-L1 gene. 
   
   
       58 - 62 . (canceled) 
   
   
       63 . An isolated or recombinant polypeptide complex comprising at least one of: a recombinant PC-1-L3 polypeptide or a recombinant polycystin 2-L1 polypeptide, the complex further comprising at least one of: a PC-1-L3 polypeptide, a polycystin 2-L1 polypeptide, a recombinant PC-1-L3 polypeptide or a recombinant polycystin 2-L1 polypeptide. 
   
   
       64 - 68 . (canceled) 
   
   
       69 . A knock out non-human animal comprising a defect in a native PKD1-L3 taste receptor gene or a defect in native PKD1-L3 gene expression. 
   
   
       70 - 81 . (canceled)