Protein Information

ID 1485
Name transducin
Synonyms G protein alpha transducing 1; GBT 1; GBT1; GNAT 1; GNAT1; GNATR; Guanine nucleotide binding protein G(T) alpha 1 subunit; Guanine nucleotide binding protein alpha transducing activity polypeptide 1…

Compound Information

ID 336
Name strychnine
CAS strychnidin-10-one

Reference

PubMed Abstract RScore(About this table)
17253962 Sainz E, Cavenagh MM, Gutierrez J, Battey JF, Northup JK, Sullivan SL: Functional characterization of human bitter taste receptors. . Biochem J. 2007 May 1;403(3):537-43.
The T2Rs belong to a multi-gene family of G-protein-coupled receptors responsible for the detection of ingested bitter-tasting compounds. The T2Rs are conserved among mammals with the human and mouse gene families consisting of about 25 members. In the present study we address the signalling properties of human and mouse T2Rs using an in vitro reconstitution system in which both the ligands and G-proteins being assayed can be manipulated independently and quantitatively assessed. We confirm that the mT2R5, hT2R43 and hT2R47 receptors respond selectively to micromolar concentrations of cycloheximide, aristolochic acid and denatonium respectively. We also demonstrate that hT2R14 is a receptor for aristolochic acid and report the first characterization of the ligand specificities of hT2R7, which is a broadly tuned receptor responding to strychnine, quinacrine, chloroquine and papaverine. Using these defined ligand-receptor interactions, we assayed the ability of the ligand-activated T2Rs to catalyse GTP binding on divergent members of the G (alpha) family including three members of the G (alphai) subfamily (transducin, G (alphai1) and G (alphao)) as well as G (alphas) and G (alphaq). The T2Rs coupled with each of the three G (alphai) members tested. However, none of the T2Rs coupled to either G (alphas) or G (alphaq), suggesting the T2Rs signal primarily through G (alphai)-mediated signal transduction pathways. Furthermore, we observed different G-protein selectivities among the T2Rs with respect to both G (alphai) subunits and G (betagamma) dimers, suggesting that bitter taste is transduced by multiple G-proteins that may differ among the T2Rs.
1(0,0,0,1)