GLUT4 Redistribution Assay

• Designed to assay compounds for their ability to modulate GLUT4 translocation
• 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
• Easy to use: Just plate cells, add compounds, and image

The GLUT4 glucose transporter is essential for insulin-stimulated glucose uptake, and is expressed primarily in adipose and muscle tissues. In response to insulin, intracellular GLUT4 vesicles translocate to cytoskeletal structures near the cell surface, followed by fusion of the GLUT4 vesicles with the plasma membrane. Defective uptake of glucose via GLUT4 in response to insulin is a central feature of obesity and type 2 diabetes.

Figure 1. Translocation of GLUT4-EGFP in response to insulin. Cells were treated with 50 nM insulin for 5 min (right panel) or vehicle control (left panel). Arrows indicate the GLUT4-EGFP translocation from cytoplasmic vesicles to the plasma membrane that is detected by the image analysis algorithm.

Figure 2. Concentration response curves in the GLUT4 assay: A) Insulin concentration response in the GLUT4 agonist assay (n = 8). The EC₅₀ is ~16 nM. Cells were treated with insulin for 5 min. Cells were then fixed and GLUT4 translocation was measured using the Cellomics ArrayScan® V^TI Reader and the CytoCellMemTransV2 BioApplication. % activity was calculated relative to the positive (50 nM insulin) and negative control. B) Wortmannin concentration response in the GLUT4 assay run in antagonist format (n = 8). Cells were preincubated for 20 min with a half log dilution series of wortmannin, followed by a 5 minute treatment with 20 nM insulin. Cells were then fixed and analyzed on the Cellomics ArrayScan® V^TI Reader. % activity was calculated relative to the positive (100 nM wortmannin) and negative control. The EC₅₀ of wortmannin is ~4 nM.