Molecular Determinants of the Intrinsic Efficacy of the Antipsychotic Aripiprazole

Carmen Klein Herenbrink, Ravi Verma, Herman D. Lim, Anitha Kopinathan, Alastair Keen, Jeremy Shonberg, Christopher J. Draper-Joyce, Peter J. Scammells, Arthur Christopoulos, Jonathan A. Javitch, Ben Capuano, Lei Shi, J. Robert Lane

Research output: Contribution to journalArticleResearchpeer-review

17 Citations (Scopus)

Abstract

Partial agonists of the dopamine D2 receptor (D2R) have been developed to treat the symptoms of schizophrenia without causing the side effects elicited by antagonists. The receptor-ligand interactions that determine the intrinsic efficacy of such drugs, however, are poorly understood. Aripiprazole has an extended structure comprising a phenylpiperazine primary pharmacophore and a 1,2,3,4-tetrahydroquinolin-2-one secondary pharmacophore. We combined site-directed mutagenesis, analytical pharmacology, ligand fragments, and molecular dynamics simulations to identify the D2R-aripiprazole interactions that contribute to affinity and efficacy. We reveal that an interaction between the secondary pharmacophore of aripiprazole and a secondary binding pocket defined by residues at the extracellular portions of transmembrane segments 1, 2, and 7 determines the intrinsic efficacy of aripiprazole. Our findings reveal a hitherto unappreciated mechanism for fine-tuning the intrinsic efficacy of D2R agonists.

Original languageEnglish
Pages (from-to)1780-1792
Number of pages13
JournalACS Chemical Biology
Volume14
Issue number8
DOIs
Publication statusPublished - 16 Aug 2019

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