Structural basis of β-glucopyranoside salicin recognition by a human bitter taste GPCR

作者：Xin Wang, Cui Zhou, Weizhen Ao, Lijie Wu, Yiran Wu, Weixiu Xu, Shenhui Liu, Qiwen Tan, Ling Wang, Fei Zhao, Junlin Liu, Yuan Pei, Suwen Zhao, Tian Hua · 发表于：Cell Reports · 年份：2025 · DOI：10.1016/j.celrep.2025.115604 · 被引用次数：16 · 研究领域：Biochemical Analysis and Sensing Techniques、Advanced Chemical Sensor Technologies、Chromatography in Natural Products

The human perception of bitterness is mediated by type 2 taste receptors (TAS2Rs), which recognize a broad array of bitter substances with distinct chemical properties. TAS2R16 exhibits a pronounced selectivity for β-glucoside-moiety-containing compounds, such as salicin from willow bark. However, the molecular mechanism of moiety-specific recognition and receptor activation in TAS2R16 remains unclear. Here, we present cryoelectron microscopy structures of the salicin-activated human TAS2R16 complexed with gustducin and G i1 and G i2 proteins. The binding mode of salicin with TAS2R16 and the specific interactions of the β-D-glucopyranoside moiety are detailed. Together with molecular docking and mutagenesis data, this study uncovers the structural underpinnings of TAS2R16's group-specific recognition, receptor activation, and subsequent gustducin and G i protein coupling. These findings advance our understanding of human bitter taste receptors and provide a foundation for structural modifications of bitter glycosides, opening potential therapeutic applications.