Allosteric Modulators Enhancing GLP-1 Binding to GLP-1R via a Transmembrane Site
Jiang Wang, Dehua Yang, Xi Cheng, Linlin Yang, Zhaohui Wang, Antao Dai, Xiaoqing Cai, Chao Zhang, Elita Yuliantie, Qiaofeng Liu, Hualiang Jiang, Hong Liu, Ming‐Wei Wang, Huaiyu Yang
Abstract
The glucagon-like peptide-1 receptor (GLP-1R) is a well-established drug target for the treatment of type II diabetes. The development of small-molecule positive allosteric modulators (PAMs) of GLP-1R is a promising therapeutic strategy. Here, we report the discovery and characterization of PAMs with distinct chemotypes, binding to a cryptic pocket formed by the cytoplasmic half of TM3, TM5, and TM6. Molecular dynamic simulations and mutagenesis studies indicate that the PAM enlarges the orthosteric pocket to facilitate GLP-1 binding. Further signaling assays characterized their probe-dependent signaling profiles. Our findings provide mechanistic insights into fine-tuning GLP-1R via this allosteric pocket and open up new avenues to design small-molecule drugs for class B G-protein-coupled receptors.