The expression of alpha-gustducin, a G protein alpha subunit involved in bitter and sweet taste transduction, was investigated in chemosensory tissues of adult mice. By immunohistochemistry, alpha gustducin was absent in the olfactory neuroepithelium. Instead, alpha gustducin was expressed in a subset of bipolar cells in the proliferative zone of the vomeronasal neuroepithelium as well as in taste buds. Northern blot analysis confirmed the presence of alpha gustducin in isolated vomeronasal organs. Moreover, immunohisto- chemistry revealed the expression of alpha gustducin in scattered cells of the nasal respiratory epithelium. These results show for the first time that alpha gustducin is expressed in chemosensory tissue outside the alimentary tract, suggesting that common transduction mechanisms could be shared by apparently unrelated chemosensory tissues.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1046/j.1460-9568.1999.00912.x | DOI Listing |
Phytomedicine
January 2025
Department of Traditional Chinese Medicine, College of Pharmaceutical Sciences and Traditional Chinese Medicine, Southwest University, Chongqing 400715, China. Electronic address:
Background: Coptidis Rhizoma, a classic bitter traditional Chinese medicine, can lead to digestive dysfunction when long-term use according to traditional experience. Bitter taste receptors have been found to regulate gastrointestinal smooth muscle contraction. Coptidis Rhizoma alkaloids are potential agonists for bitter taste receptors, but whether they can induce gastrointestinal dysfunction via bitter taste receptors is not clear.
View Article and Find Full Text PDFNat Commun
November 2024
Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, Israel.
Bitter taste receptors (TAS2Rs), a subfamily of G-protein coupled receptors (GPCRs) expressed orally and extraorally, elicit signaling in response to a large set of tastants. Among 25 functional TAS2Rs encoded in the human genome, TAS2R14 is the most promiscuous, and responds to hundreds of chemically diverse ligands. Here we present the cryo-electron microscopy (cryo-EM) structure of the human TAS2R14 in complex with its signaling partner gustducin, and bound to flufenamic acid (FFA), a clinically approved nonsteroidal anti-inflammatory drug.
View Article and Find Full Text PDFJ Phys Chem B
September 2024
Materials and Process Simulation Center (139-74), California Institute of Technology, Pasadena, California 91125, United States.
The heterodimeric sweet taste receptor, TAS1R2/1R3, is a class C G protein-coupled receptor (GPCR) that couples to gustducin (Gt), a G protein (GP) specifically involved in taste processing. This makes TAS1R2/1R3 a possible target for newly developing low caloric ligands that taste sweet to address obesity and diabetes. The activation of TAS1R2/1R3 involves the insertion of the GαP C-terminus of the GP into the GPCR in response to ligand binding.
View Article and Find Full Text PDFPflugers Arch
November 2024
Department of Oral Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Taste buds contain 2 types of GABA-producing cells: sour-responsive Type III cells and glial-like Type I cells. The physiological role of GABA, released by Type III cells is not fully understood. Here, we investigated the role of GABA released from Type III cells using transgenic mice lacking the expression of GAD67 in taste bud cells (Gad67-cKO mice).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!