Therapeutic strategies for diseases caused by loss-of-function mutations in G protein-coupled receptors

As one of the largest families of cell membrane proteins, G protein-coupled receptors (GPCRs) are involved in regulating almost all physiological processes by transducing extracellular signals into the cytoplasm. Since the first discovery of naturally occurring mutations in Rhodopsin gene in 1990, hundreds of loss-of-function mutations in multiple GPCRs have been identified to be pathogenic for more than 30 diverse human diseases, making these defective receptors important drug targets for personalized medicine. In this review, we aim to elucidate the etiologies of five common inherited diseases caused by six of the most extensively studied GPCRs. The molecular basis and classification of inactivating mutations in GPCRs are also reviewed. The available therapeutic approaches directed against different classes of mutants, especially pharmacological chaperones targeting intracellularly retained mutants, reported during the past two decades, are systematically summarized.