This proposal seeks to elucidate how G protein-coupled receptors (GPCRs) are regulated by naturally produced ligands and addictive drugs, focusing at the cell biological level as the critical bridge linking molecular and systems-level events and understanding. GPCRs represent the largest family of signaling receptors, comprise in aggregate the largest class of therapeutic drug targets, and mediate directly or indirectly the effects of all addictive drugs. Accordingly, while addictive drug action in the CNS is our particular focus, the proposed studies have broad potential application across GPCR family members and pathophysiological processes. Our over-arching goal is to develop a fundamental understanding of GPCR regulation, discovering the underlying cell biology and then elucidating its molecular basis, and through this path discover new targets and strategies for potential therapeutic manipulation of addictive and other complex brain disorders that are characterized by underlying disturbances of GPCR signaling or GPCR-dependent physiological regulation. Progress in the previous funding period focused on defining sites of regulatory phosphorylation in the mu opioid receptor, accomplishing this in intact human cells expressing the full spectrum of endogenous kinases at native levels. We defined two critical regions of phosphorylation and carried out detailed cell biological analysis of one of them, both in a heterologous cell model and a physiologically relevant population of CNS- derived neurons. During the course of these studies we made some major unanticipated progress, including development of conformational biosensor technology, discovery of GPCR signaling via heterotrimeric G proteins from endosomes, and discovery of an unprecedented behavior of arrestin proteins suggesting a new cellular operating mode of arrestins, downstream of and after dissociating from an activating GPCR. The proposed studies seek to develop and extend these fundamental new observations and develop them to the point of rational consideration as new molecular targets and cell-based strategies for therapeutics.

Public Health Relevance

Drug addiction is an enormous public health problem with devastating individual, societal and financial ramifications, and for which there are presently no curative biological therapies. The proposed studies seek to develop a fundamental understanding of the cellular effects and disturbances produced by addictive drugs, focusing on opioids as an important and experimentally advantageous example. This program of research has the potential to discover altogether new targets and strategies to consider for therapeutics of addictive disorders.

National Institute of Health (NIH)
National Institute on Drug Abuse (NIDA)
Research Project (R01)
Project #
Application #
Study Section
Molecular and Integrative Signal Transduction Study Section (MIST)
Program Officer
Wu, Da-Yu
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of California San Francisco
Schools of Medicine
San Francisco
United States
Zip Code
Siljee, Jacqueline E; Wang, Yi; Bernard, Adelaide A et al. (2018) Subcellular localization of MC4R with ADCY3 at neuronal primary cilia underlies a common pathway for genetic predisposition to obesity. Nat Genet 50:180-185
Eichel, Kelsie; Jullié, Damien; Barsi-Rhyne, Benjamin et al. (2018) Catalytic activation of ?-arrestin by GPCRs. Nature 557:381-386
Eichel, Kelsie; von Zastrow, Mark (2018) Subcellular Organization of GPCR Signaling. Trends Pharmacol Sci 39:200-208
Kim, Min Woo; Wang, Wenjing; Sanchez, Mateo I et al. (2017) Time-gated detection of protein-protein interactions with transcriptional readout. Elife 6:
Uchida, Yasunori; Rutaganira, Florentine U; Jullié, Damien et al. (2017) Endosomal Phosphatidylinositol 3-Kinase Is Essential for Canonical GPCR Signaling. Mol Pharmacol 91:65-73
Irannejad, Roshanak; Pessino, Veronica; Mika, Delphine et al. (2017) Functional selectivity of GPCR-directed drug action through location bias. Nat Chem Biol 13:799-806
O'Hayre, Morgan; Eichel, Kelsie; Avino, Silvia et al. (2017) Genetic evidence that ?-arrestins are dispensable for the initiation of ?2-adrenergic receptor signaling to ERK. Sci Signal 10:
Tsvetanova, Nikoleta G; Trester-Zedlitz, Michelle; Newton, Billy W et al. (2017) G Protein-Coupled Receptor Endocytosis Confers Uniformity in Responses to Chemically Distinct Ligands. Mol Pharmacol 91:145-156
Lobingier, Braden T; Hüttenhain, Ruth; Eichel, Kelsie et al. (2017) An Approach to Spatiotemporally Resolve Protein Interaction Networks in Living Cells. Cell 169:350-360.e12
Varandas, Katherine C; Irannejad, Roshanak; von Zastrow, Mark (2016) Retromer Endosome Exit Domains Serve Multiple Trafficking Destinations and Regulate Local G Protein Activation by GPCRs. Curr Biol 26:3129-3142

Showing the most recent 10 out of 54 publications