Gustducin is a taste-cell-specific G protein closely related to the transducins

@article{Mclaughlin1992GustducinIA,
  title={Gustducin is a taste-cell-specific G protein closely related to the transducins},
  author={S K Mclaughlin and Robert F. Margolskee},
  journal={Nature},
  year={1992},
  volume={357},
  pages={563-569}
}
A novel G protein α-subunit (α-gustducin) has been identified and cloned from taste tissue, α-Gustducin messenger RNA is expressed in taste buds of all taste papillae (circumvallate, foliate and fungiform); it is not expressed in non-sensory portions of the tongue, nor is it expressed in the other tissues examined, α-Gustducin most closely resembles the transducins (the rod and cone photoreceptor G proteins), suggesting that gustducin's role in taste transduction is analogous to that of… 
Gustducin and transducin: a tale of two G proteins.
TLDR
The primary sequence of alpha gustducin shows similarities to the transducins in the receptor interaction domain and the phosphodiesterase activation site, which suggest that gust Ducin and transducin regulate taste cell phosphodiesters, probably in bitter taste transduction.
Gustducin and its Role in Taste
TLDR
A proposed mechanism for α-gustducin involves coupling specific cell-surface receptors with a cyclic nucleotide phosphodiesterase which would open a cyclIC nucleotide-suppressible cation channel leading to influx of calcium, and ultimately leading to release of neurotransmitter.
Differential Expression of α-Gustducin in Taste Bud Populations of the Rat and Hamster
TLDR
The hypothesis that α-gustducin is involved in the transduction of both sweet- and bitter-tasting stimuli by mammalian taste receptor cells is supported.
Umami Taste Responses Are Mediated by α-Transducin and α-Gustducin
TLDR
It is found that αt-rod played no role in taste responses to the salty, bitter, and sweet compounds tested or to IMP but was involved in the umami taste of MSG and MPG.
Differential expression of alpha-gustducin in taste bud populations of the rat and hamster.
TLDR
The hypothesis that alpha-gustducin is involved in the transduction of both sweet- and bitter-tasting stimuli by mammalian taste receptor cells is supported.
Functional Interaction between T2R Taste Receptors and G-Protein α Subunits Expressed in Taste Receptor Cells
TLDR
A heterologous expression system is used to determine a specific domain of gustducin necessary for T2R coupling and expresses G16 protein chimeras with the corresponding domain from other Gαi proteins, cone-transducin (Gαt2, G αi2, and Gαz), which could be useful tools to analyze the functions of many orphan G-protein-coupled taste receptors.
Molecular Functional Interaction between T 2 R Taste Receptors and G-Protein Subunits Expressed in Taste Receptor Cells
TLDR
The present G 16-based chimeras could be useful tools to analyze the functions of many orphan G-protein-coupled taste receptors.
α‐Gustducin expression in the vomeronasal organ of the mouse
TLDR
Results show for the first time that α gustducin is expressed in chemosensory tissue outside the alimentary tract, suggesting that common transduction mechanisms could be shared by apparently unrelated chemos Sensory tissues.
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