GLP1R Redistribution Assay

• Designed to assay compounds for their ability to internalize GLP1 receptor
• Coupled to EGFP for easy monitoring of the cellular translocation event
• Robust cell-based assay for use in high content analysis and fluorescence microscope applications

• Biologically relevant data: Compounds tested in a cellular environment
• Validated: Functionally tested cells provided with an optimized assay protocol
• Assay to use: Just plate cells, add compounds, and image

Glucagon-like peptide 1 (GLP1) is an intestinal hormone. It is secreted into the blood by the intestinal L cells in response to food intake. GLP1 receptor (GLP1R) is a G-protein coupled receptor of the glucagons/secretin/vasoactive intestinal peptide receptor subfamily. GLP1R couples to Gs and receptor activation leads to an increase in cellular cAMP. Upon binding of ligand the receptor is internalized/endocytosed and recycled to the cell surface. GLP1R is expressed on the surface of pancreatic β-cells and ligand binding results in activation of adenylate cyclase and insulin release. Additional effects of GLP1R activation include suppression of glucagon secretion and reduction in appetite, food intake and gastric emptying. These functions make the GLP1 receptor a promising target for treatment of type 2 diabetes using GLP1R agonists.

Figure 1. Internalization of GLP1R-EGFP stimulated with GLP1. DMSO control (left panel) and cells treated with 100 nM GLP1 for 1 hr (right panel). Arrows indicate the GLP1R-EGFP internalization that is detected by the image analysis algorithm.

Figure 2. GLP1 concentration response in the GLP1R assay. Concentration-response curves of wortmmanin in the Akt1. Concentration response was measured in 9 point half log dilution series (n=16). Cells were incubated with GLP1 for 1 hr. Cells were then fixed and internalization was measured using the Cellomics ArrayScan® V^TI Reader and the SpotDetectorV3 BioApplication. % activity was calculated relative to the positive (100 nM GLP1) and negative control (0.25% DMSO). The EC₅₀ of GLP1 is ~70 nM.