Abstract: A model of transmembrane helices of dopamine D2 receptor was constructed using the X-ray coordinates of bacteriorhodopsin (BR) as a template. Based on the results from the model and the sitedirected mutagenesis experience, the binding pocket, including nine amino acid residues beside indispensable Asp86, Ser141 and Ser144 residues, was defined. In order to testify the 3D-structure of dopamine D2 receptor and specially test the binding sites, two sets of D2 receptor agonists (one was rigid and the other flexible) were selected for docking. A good result of correlation between -logIC50 and binding energy Eb indicates that the predicted model is reliable for the investigation of the receptor-ligand interaction and design of new active molecules.

Key words: Dopamine D2 receptor, 3D-structure prediction, DOCK