Structure of C lass B GPCRs : new horizons for drug discovery

C lass B GPCRs of the secretin family are important drug targets in many human diseases including diabetes, neurodegeneration, cardiovascular disease and psychiatric disorders. X ‐ray crystal structures for the glucagon receptor and corticotropin‐releasing factor receptor 1 have now been published. In this review, we analyse the new structures and how they compare with each other and with C lass A and F receptors. We also consider the differences in druggability and possible similarity in the activation mechanisms. Finally, we discuss the potential for the design of small‐molecule modulators for these important targets in drug discovery. This new structural insight allows, for the first time, structure‐based drug design methods to be applied to C lass B GPCRs .