演題概要

基盤セッション

第3日　5月17日（水）　09:51～10:09　A会場（特別会議場）

3A-O-0951　　PDF

ネイティブ質量分析によるGタンパク質共役受容体（GPCR）の薬剤応答評価

(¹横市大院生命医・ ²理研・ ³サントリー生科財団)
^o田尻道子¹・ 今井駿輔²・ 小沼剛¹・ 島本啓子³・ 嶋田一夫²・ 明石知子¹

G protein-coupled receptors (GPCRs) are seven-transmembrane receptors responsible for many physiological processes. Although GPCRs are important drug targets because of their involvement in various diseases, screening for effective binding and activity-regulating molecules remains challenging. Native mass spectrometry (MS) has been attracting interest as a useful analytical tool for membrane proteins. However, GPCRs are structurally unstable among membrane proteins, and it is extremely difficult to observe their complexes with ligands. The β₂ adrenergic receptor (β₂AR) is a typical GPCR, and it is known that binding of Nanobody 80 (Nb80) or mini-G_s stabilizes the active form of β₂AR. In addition, the activation levels, i.e., efficacy, by the ligand binding varies depending on the ligands, and the ligand efficacy reflects to the drug potency. In this study, we investigated the efficacy of ligands by observing the complexes of β₂AR and Nb80 or mini-G_s quantitatively in the presence of ligands using native MS. It was found that there is a strong correlation between the β₂AR-mini-G_s or -Nb80 complex ratios observed in mass spectra and ligand responses obtained using cell-based assays quantitatively.