RT Journal Article SR Electronic T1 Functional Interaction between Trace Amine-Associated Receptor 1 and Dopamine D2 Receptor JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 416 OP 425 DO 10.1124/mol.111.073304 VO 80 IS 3 A1 Stefano Espinoza A1 Ali Salahpour A1 Bernard Masri A1 Tatyana D. Sotnikova A1 Mirko Messa A1 Larry S. Barak A1 Marc G. Caron A1 Raul R. Gainetdinov YR 2011 UL http://molpharm.aspetjournals.org/content/80/3/416.abstract AB The ability of dopamine receptors to interact with other receptor subtypes may provide mechanisms for modulating dopamine-related functions and behaviors. In particular, there is evidence suggesting that the trace amine-associated receptor 1 (TAAR1) affects the dopaminergic system by regulating the firing rate of dopaminergic neurons or by altering dopamine D2 receptor (D2R) responsiveness to ligands. TAAR1 is a Gαs protein-coupled receptor that is activated by biogenic amines, “trace amines,” such as β-phenylethylamine (β-PEA) and tyramine that are normally found at low concentrations in the mammalian brain. In the present study, we investigated the biochemical mechanism of interaction between TAAR1 and D2R and the role this interaction plays in D2R-related signaling and behaviors. Using a bioluminescence resonance energy transfer biosensor for cAMP, we demonstrated that the D2R antagonists haloperidol, raclopride, and amisulpride were able to enhance selectively a TAAR1-mediated β-PEA increase of cAMP. Moreover, TAAR1 and D2R were able to form heterodimers when coexpressed in human embryonic kidney 293 cells, and this direct interaction was disrupted in the presence of haloperidol. In addition, in mice lacking TAAR1, haloperidol-induced striatal c-Fos expression and catalepsy were significantly reduced. Taken together, these data suggest that TAAR1 and D2R have functional and physical interactions that could be critical for the modulation of the dopaminergic system by TAAR1 in vivo.