Tools for investigating functional interactions between ligands and G-protein-coupled receptors.

A general assay for evaluating functional interactions between ligands and G-protein-coupled receptors within minutes has been developed. The system uses the principles employed by animals such as reptiles, amphibians and fish to control their colors. In nature, activation of G-protein-coupled receptors expressed by skin cells called chromatophores effects pigment redistribution within the cells to change an animal's coloration. The in vitro 'chameleon in a dish' equivalent can use essentially any cloned G-protein-coupled receptor.