Proximity Labeling of D1-Like Dopamine Receptors Captures Distinct Cellular Environments and Uncovers Trafficking Proteins That Regulate DA-Mediated Behaviors in Drosophila

This multifunctional role of DA is due to receptor-specific signaling in specific subcellular environments that remain uncharacterized. Here we used Turbo-mediated proximity labeling in human cells to characterize the proximal environments of two <i>Drosophila</i> D1-like DA receptors (Dop1R1 and Dop1R2) in basal and DA-activation environments.

DA drives both Dop1R1-Turbo and Dop1R2-Turbo to recruit β-arrestin 2, and Dop1R1-Turbo showed ligand-driven proximity to G-protein receptor kinase 3, members of clathrin-mediated endocytosis pathways, and WASH complex-mediated endosomal trafficking pathways. Additionally, we show evidence that Dop1R1 and Dop1R2 reside in distinct domains on the cell surface. <i>In vivo</i> disruption of <i>Drosophila</i> orthologues of Dop1R proximal proteins revealed three trafficking proteins, Sec24AB, Krz (beta-arrestin 2), and CG13887, that regulate R1-mediated learning, starvation-induced attraction to odors, and DA-mediated cAMP responses in memory circuits.