title: Sorting nexin 27 regulation of G protein-gated inwardly rectifying K⁺ channels attenuates in vivo cocaine response.
abstract: The subcellular pathways that regulate G protein-gated inwardly rectifying potassium (GIRK or Kir3) channels are important for controlling the excitability of neurons. Sorting nexin 27 (SNX27) is a PDZ-containing protein known to bind GIRK2c/GIRK3 channels, but its function in vivo is poorly understood. Here, we investigated the role of SNX27 in regulating GIRK currents in dopamine (DA) neurons of the ventral tegmental area (VTA). Mice lacking SNX27 in DA neurons exhibited reduced GABABR-activated GIRK currents but had normal Ih currents and DA D2R-activated GIRK currents. Expression of GIRK2a, an SNX27-insensitive splice variant, restored GABABR-activated GIRK currents in SNX27-deficient DA neurons. Remarkably, mice with significantly reduced GABABR-activated GIRK currents in only DA neurons were hypersensitive to cocaine and could be restored to a normal locomotor response with GIRK2a expression. These results identify a pathway for regulating excitability of VTA DA neurons, highlighting SNX27 as a promising target for treating addiction.
authors.affiliation: Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Graduate Program in Biology, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Michaelanne B
authors.initials: MB
authors.lastname: Munoz
authors.affiliation: Peptide Biology Laboratories, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA; Graduate Program in Biology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA. Electronic address: paul.slesinger@mssm.edu.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Slesinger
mesh_terms: D000818:Animals; D003042:Cocaine / Q000633:toxicity*; D005260:Female; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009473:Neuronal Plasticity / Q000187:drug effects / Q000235:genetics; D009924:Organ Culture Techniques; D011485:Protein Binding / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D058305:Sorting Nexins / Q000172:deficiency / Q000502:physiology*; D017557:Ventral Tegmental Area / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
chemical_list: D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; C497069:Kcnj6 protein, mouse; C500393:Snx27 protein, mouse; D058305:Sorting Nexins; D003042:Cocaine