Abstract

The generation of G-protein coupled receptors (GPCR)- G proteins complex is one of the bottlenecks in cryoEM structure determination to support structure based drug design. The complex formation requires the presence of agonist and identifying the optimal condition is a time consuming iterative process. Here, we show the development of utilising homogeneous time-resolved fluorescence (HTRF) technology to detect the complex formation between glucagon-like peptide receptor (GLP-1R), a class B GPCR and G proteins. We have protein engineered the GLP-1R and Gβ protein with specific tags and treated with a known small molecule agonist, “Danuglipron”. The HTRF assay platform is suitable with cell lysate with > 3x S/B assay window and a Z´value of >0.5. The solubilized and purified material are also compatible which give > 2x and > 1.5x HTRF activation signal, respectively. We have also demonstrated the platform can be applied to determine optimal GPCR-G proteins complex formation such as construct optimization, detergent screen, buffer screen and expression ratio optimization via high dimensional experiments (HDE) analysis. Therefore, the platform can be serve as a rapid screening tool to optimizing reagent generation to support cryoEM structure determination and facilitate structure based drug design.