Interaction of covalently modified beta arrestins with stimulated G protein coupled receptors
The present invention relates to a modified arrestin which includes an arrestin molecule and a ubiquitin molecule. This modified arrestin has an increased affinity for a GPCR, and traffics with the GPCR into endosomes. The present invention further relates to a method of screening compounds and sample solutions for a GPCR agonist, antagonist, inverse agonist, or desensitization active compound. The modified arrestin is useful in the methods of the present invention.