Abstract: The present invention relates to the discovery that the T1R receptors assemble to form functional taste receptors. Particularly, it has been discovered that co-expression of T1R1 and T1R3 results in a taste receptor that responds to umami taste stimuli, including monosodium glutamate. Also, it has been discovered that co-expression of the T1R2 and T1R3 receptors results in a taste receptor that responds to sweet taste stimuli including naturally occurring and artificial sweeteners. Also the present invention relates to the use of hetero-oligomeric taste receptors comprising T1R1/T1R3 and T1R2/T1R3 in assays to identify compounds that respectively respond to umami taste stimuli and sweet taste stimuli. Further, the invention relates to the constitutive of cell lines that stably or transiently co-express a combination of T1R1 and T1R3; or T1R2 and T1R3; under constitutive or inducible conditions.

Abstract: Methods for expressing a heteromeric taste receptor that responds to umami taste stimuli are provided. These methods comprise the co-expression of T1R1 and T1R3 nucleic acid sequences in a host cell that desirably also expresses a G protein that couples therewith, e.g., G?15 and G?16 or gustducin. In preferred embodiments, the host cells will be mammalian cells or Xenopus oocytes. These nucleic acid sequences are expressed constitutively or under inducible conditions. In preferred embodiments, the methods will yield mammalian cells that stably express a T1R1/T1R3 umami taste receptor under inducible conditions, e.g., HEK-293 cells that express G?15.

Abstract: The present invention relates to the discovery that the T1R receptors assemble to form functional taste receptors. Particularly, it has been discovered that co-expression of T1R1 and T1R3 results in a taste receptor that responds to umami taste stimuli, including monosodium glutamate. Also, it has been discovered that co-expression of the T1R2 and T1R3 receptors results in a taste receptor that responds to sweet taste stimuli including naturally occurring and artificial sweeteners. Also the present invention relates to the use of hetero-oligomeric taste receptors comprising T1R1/T1R3 and T1R2/T1R3 in assays to identify compounds that respectively respond to umami taste stimuli and sweet taste stimuli. Further, the invention relates to the constitutive of cell lines that stably or transiently co-express a combination of T1R1 and T1R3; or T1R2 and T1R3; under constitutive or inducible conditions.

Abstract: Methods for expressing a heteromeric taste receptor that responds to umami taste stimuli are provided. These methods comprise the co-expression of T1R1 and T1R3 nucleic acid sequences in a host cell that desirably also expresses a G protein that couples therewith, e.g., G?15 and G?16 or gustducin. In preferred embodiments, the host cells will be mammalian cells or Xenopus oocytes. These nucleic acid sequences are expressed constitutively or under inducible conditions. In preferred embodiments, the methods will yield mammalian cells that stably express a T1R1/T1R3 umami taste receptor under inducible conditions, e.g., HEK-293 cells that express G?15.