The abuse liability of psychostimulants is well established and represents a significant public health concern. Unfortunately effective therapeutic strategies for psychostimulant abuse are sorely lacking since, at the cellular level, their mechanism of action is not well understood. Recent investigations by our group have revealed a vital role for the scaffolding protein beta-arrestin-2 and the Akt/GSK3 signaling pathway in mediating responses to psychostimulant drugs in vivo (Beaulieu et al., 2007 Cell). Through the execution of two complimentary aims, I will define the role of beta- arrestin-2 in the actions of psychostimulant drugs in the direct versus indirect pathways of the basal ganglia.
In Specific Aim 1 I will generate novel transgenic mouse lines to facilitate the isolation of beta-arrestin-2 signaling complexes in direct and indirect pathways in vivo. Although previous work demonstrated the formation of beta-arrestin-2 signaling complexes in mixed populations of striatal medium spiny neurons (MSNs), our working hypothesis is that beta-arrestin-2-mediated signaling is differentially engaged by psychostimulants in direct versus indirect pathway-projecting MSNs thereby impacting dopamine-associated behaviors. The generation of the proposed transgenic line will enable the identification of pathway-specific biochemical processes that could not be resolved from the previous method.
In Specific Aim 2 I will make use of the novel transgenic mouse lines proposed in Aim 1 to isolate distinct beta-arrestin-2 signaling complexes in direct versus indirect pathway- projecting MSNs in response to select psychostimulant drugs. By monitoring beta-arrestin-2 function in vivo I expect to elucidate common mechanisms that are central to the expression of dopamine- mediated behaviors. As such, this work promises to significantly advance our understanding of the signaling mechanisms employed by psychostimulant drugs and to identify novel pharmacological targets for a wide range of disorders involving dysfunction of the dopamine system.

Public Health Relevance

Statement Psychostimulant abuse is pervasive in the United States. The proposed studies will fill critical gaps in our understanding of the cellular actions of these widely abused drugs in the brain and thereby, aide the development of effective therapeutics to combat the abuse of psychostimulants. Understanding the actions of these drugs at both the cellular and neural circuitry level also promises to provide novel insights relevant to other neurological disorders involving dysfunction of the dopamine system and basal ganglia.

National Institute of Health (NIH)
National Institute on Drug Abuse (NIDA)
Postdoctoral Individual National Research Service Award (F32)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-F01-L (20))
Program Officer
Babecki, Beth
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Duke University
Anatomy/Cell Biology
Schools of Medicine
United States
Zip Code
Daigle, Tanya L; Ferris, Mark J; Gainetdinov, Raul R et al. (2014) Selective deletion of GRK2 alters psychostimulant-induced behaviors and dopamine neurotransmission. Neuropsychopharmacology 39:2450-62
Gregory, K J; Herman, E J; Ramsey, A J et al. (2013) N-aryl piperazine metabotropic glutamate receptor 5 positive allosteric modulators possess efficacy in preclinical models of NMDA hypofunction and cognitive enhancement. J Pharmacol Exp Ther 347:438-57
Evron, Tama; Daigle, Tanya L; Caron, Marc G (2012) GRK2: multiple roles beyond G protein-coupled receptor desensitization. Trends Pharmacol Sci 33:154-64
Daigle, Tanya L; Wetsel, William C; Caron, Marc G (2011) Opposite function of dopamine D1 and N-methyl-D-aspartate receptors in striatal cannabinoid-mediated signaling. Eur J Neurosci 34:1378-89