A candidate taste receptor gene near a sweet taste locus.
The mechanisms underlying sweet taste in mammals have been elusive. Although numerous studies have implicated G proteins in sweet taste detection, the expected G protein-coupled receptors have not been found. Here we describe a candidate taste receptor gene, T1r3, that is located at or near the mouse Sac locus, a genetic locus that controls the detection of certain sweet tastants. T1R3 differs in amino acid sequence in mouse strains with different Sac phenotypes ('tasters' versus 'nontasters'). In addition, a perfect correlation exists between two different T1r3 alleles and Sac phenotypes in recombinant inbred mouse strains. The T1r3 gene is expressed in a subset of taste cells in circumvallate, foliate and fungiform taste papillae. In circumvallate and foliate papillae, most T1r3-expressing cells also express a gene encoding a related receptor, T1R2, raising the possibility that these cells recognize more than one ligand, or that the two receptors function as heterodimers.
Montmayeur
J P
JP
Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Liberles
S D
SD
Matsunami
H
H
Buck
L B
LB
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D002628:Chemoreceptor Cells / Q000502:physiology*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005796:Genes / Q000502:physiology*; D017403:In Situ Hybridization; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010641:Phenotype; D011110:Polymorphism, Genetic / Q000235:genetics; D013649:Taste / Q000235:genetics*; D013650:Taste Buds / Q000378:metabolism
D004247:DNA