A taste for umami

@article{Lindemann2000ATF,
  title={A taste for umami},
  author={Bernd Lindemann},
  journal={Nature Neuroscience},
  year={2000},
  volume={3},
  pages={99-100}
}
  • Bernd Lindemann
  • Published 1 February 2000
  • Chemistry, Medicine
  • Nature Neuroscience
Chaudhari and colleagues identify the taste receptor for l-glutamate, also known as umami, found in protein-rich foods. The protein they describe is a new G-protein-coupled receptor that corresponds to a truncated form of the metabotropic glutamate receptor mGluR4. 
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References

SHOWING 1-10 OF 13 REFERENCES
Receptor seeks ligand: On the way to cloning the molecular receptors for sweet and bitter taste
The cloning of two new taste receptors represents a scrumptious advance for this field of research, but determining their flavor still leaves one feeling slightly hungry
A metabotropic glutamate receptor variant functions as a taste receptor
TLDR
A GPCR cloned from rat taste buds and functionally expressed in CHO cells is described, which shows an unusual concentration–response relationship and the similarity of its properties to MSG taste suggests that this receptor is a taste receptor for glutamate.
Basic properties of umami and effects on humans
TLDR
Though the taste threshold of MSG was slightly lower than that of Na, the threshold of IMP was found to be controlled by Na, and it was found that the taste ofIMP was probably caused by glutamic acid in saliva, since IMP itself has no umami taste.
The Taste of Monosodium Glutamate: Membrane Receptors in Taste Buds
TLDR
It is concluded that mGluR4 may be a chemosensory receptor responsible, in part, for the taste of MSG.
Putative Mammalian Taste Receptors A Class of Taste-Specific GPCRs with Distinct Topographic Selectivity
TLDR
The cloning and characterization of two novel seven-transmembrane domain proteins expressed in topographically distinct subpopulations of taste receptor cells and taste buds are reported and it is proposed that these genes encode taste receptors.
Physiological evidence for ionotropic and metabotropic glutamate receptors in rat taste cells.
TLDR
The results suggest that NMDA-like receptors and at least two types of group III mGluRs are present in taste receptor cells, and these may be coactivated by MSG.
Probing the Ligand-binding Domain of the mGluR4 Subtype of Metabotropic Glutamate Receptor*
TLDR
It is suggested that the hydroxyl groups on the side chains of Ser159 and Thr182 of mGluR4 form hydrogen bonds with the α-carboxyl and α-amino groups on l-SOP, respectively, whereas Arg78 forms an electrostatic interaction with the acidic side chainsof l-serineO-phosphate or glutamate.
Taste Buds Have a Cyclic Nucleotide-activated Channel, CNGgust*
TLDR
Results from reverse transcription-polymerase chain reaction and genomic DNA cloning and characterized a CNG channel (CNGgust) as a cyclic nucleotide-activated species expressed in rat tongue epithelial tissues where taste reception takes place strongly suggest the involvement of CNG gust in taste signal transduction.
A cyclic–nucleotide–suppressible conductance activated by transducin in taste cells
TLDR
It is proposed that transducin, via phosphodiesterase, decreases cyclic nucleotide levels to activate the cyclic-nucleotide-suppressible conductance, leading to Ca2+ influx and taste-cell depolarization.
Responses to glutamate in rat taste cells.
TLDR
The findings indicate that glutamate, at concentrations at or slightly above threshold for taste in rats, produces two different membrane currents, which suggest that there may be two different sets of nonspecific cation channels in taste cells.
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