PT  - JOURNAL ARTICLE
AU  - Deanna M. Navaroli
AU  - Zachary H. Stevens
AU  - Zeljko Uzelac
AU  - Luke Gabriel
AU  - Michael J. King
AU  - Lawrence M. Lifshitz
AU  - Harald H. Sitte
AU  - Haley E. Melikian
TI  - The Plasma Membrane-Associated GTPase Rin Interacts with the Dopamine Transporter and Is Required for Protein Kinase C-Regulated Dopamine Transporter Trafficking
AID  - 10.1523/JNEUROSCI.2649-11.2011
DP  - 2011 Sep 28
TA  - The Journal of Neuroscience
PG  - 13758--13770
VI  - 31
IP  - 39
4099  - http://www.jneurosci.org/content/31/39/13758.short
4100  - http://www.jneurosci.org/content/31/39/13758.full
SO  - J. Neurosci.2011 Sep 28; 31
AB  - Dopaminergic signaling and plasticity are essential to numerous CNS functions and pathologies, including movement, cognition, and addiction. The amphetamine- and cocaine-sensitive dopamine (DA) transporter (DAT) tightly controls extracellular DA concentrations and half-life. DAT function and surface expression are not static but are dynamically modulated by membrane trafficking. We recently demonstrated that the DAT C terminus encodes a PKC-sensitive internalization signal that also suppresses basal DAT endocytosis. However, the cellular machinery governing regulated DAT trafficking is not well defined. In work presented here, we identified the Ras-like GTPase, Rin (for Ras-like in neurons) (Rit2), as a protein that interacts with the DAT C-terminal endocytic signal. Yeast two-hybrid, GST pull down and FRET studies establish that DAT and Rin directly interact, and colocalization studies reveal that DAT/Rin associations occur primarily in lipid raft microdomains. Coimmunoprecipitations demonstrate that PKC activation regulates Rin association with DAT. Perturbation of Rin function with GTPase mutants and shRNA-mediated Rin knockdown reveals that Rin is critical for PKC-mediated DAT internalization and functional downregulation. These results establish that Rin is a DAT-interacting protein that is required for PKC-regulated DAT trafficking. Moreover, this work suggests that Rin participates in regulated endocytosis.