Modeling of ligand binding to the dopamine D2 receptor

Abstract

The dopaminic receptors for a long time have been major targets for the development of new small molecules with high affinity and selectivity to treat psychiatric disorders, neurodegeneration, and drug abuse, and in other therapeutic areas. In the absence of a 3D structure for the human dopamine D2 (HDD2) receptor, the efforts for the discovery and design of new potential drugs rely on comparative models generation, docking and pharmacophore development studies. To obtain a better understanding of the HDD2 receptor binding site and the ligand-receptor interactions, a homology model of the HDD2 receptor based on the X-ray structure of the β2-adrenergic receptor was built and used to dock a set of partial agonists of the HDD2 receptor. The main characteristics of the binding mode for the HDD2 partial agonists set are given by the particular folding of a ligand and a complex network of contacts represented by stacking interactions, salt bridge and hydrogen bond formation. The characterization of the binding mode of the partial agonists at the HDD2 receptor provides the information required to generate pharmacophore models, which represent essential information for future virtual screening studies in order to identify new potential HDD2 partial agonists. © 2014 (CC) SCS.