Screening of Taste Receptors (Part 2) : Responsiveness for Some Taste Stimulants of THTR5 That Originally Cloned from the Papillae

Gタンパク質共役受容体THTR5をCHO細胞に導入し,呈味物質への応答性を検討した。THTR5クローンにおいてはGlucose, Fructose, Sorbitol, Arginine, Denatonium benzoate, Guanosin 5monophosphate disodium salt, Inosin 5'monophosphate sodium saltでの刺激により培養液上清中のPGE_2濃度が上昇した。さらに,Glucose, Fructose, Sorbitolでの刺激では培養液上清中のPGE_2濃度は呈味物質の濃度に依存的に変動した。以上のようにTHTR5はGlucose, Fructose, Sorbitolに濃度依存的な応答を示したことから糖質系甘味受容体であると推察した。
We introduced the THTR5 of the G-protein-coupled receptor into the CHO cell and examined its response to some tastants. In the case of the THTR5 clone, when stimulated by Glucose, Fructose, Sorbitol, Arginine, Guanosin 5-monophosphate disodium salt, Inosin 5'- monophosphate sodium salt and Denatonium benzoate, the concentration of the prostaglandin E_2 (PGE_2) in the culture solution rose. Due to the stimulus of Glucose, Fructose and Sorbitol, the PGE_2 concentration in the culture solution rose in accordance with the concentration of various tastants init. Thus, since the clone showed the concentration dependence-response to the sweet taste of saccharide, we guessed that this clone was a sweet taste receptor in connection with saccharide.