Ca(2+)/calmodulin-dependent protein kinase IIα (αCaMKII) controls the activity of the dopamine transporter: implications for Angelman syndrome

J Biol Chem. 2012 Aug 24;287(35):29627-35. doi: 10.1074/jbc.M112.367219. Epub 2012 Jul 9.

Abstract

The dopamine transporter (DAT) is a crucial regulator of dopaminergic neurotransmission, controlling the length and brevity of dopaminergic signaling. DAT is also the primary target of psychostimulant drugs such as cocaine and amphetamines. Conversely, methylphenidate and amphetamine are both used clinically in the treatment of attention-deficit hyperactivity disorder and narcolepsy. The action of amphetamines, which induce transport reversal, relies primarily on the ionic composition of the intra- and extracellular milieus. Recent findings suggest that DAT interacting proteins may also play a significant role in the modulation of reverse dopamine transport. The pharmacological inhibition of the serine/threonine kinase αCaMKII attenuates amphetamine-triggered DAT-mediated 1-methyl-4-phenylpyridinium (MPP(+)) efflux. More importantly, αCaMKII has also been shown to bind DAT in vitro and is therefore believed to be an important player within the DAT interactome. Herein, we show that αCaMKII co-immunoprecipitates with DAT in mouse striatal synaptosomes. Mice, which lack αCaMKII or which express a permanently self-inhibited αCaMKII (αCaMKII(T305D)), exhibit significantly reduced amphetamine-triggered DAT-mediated MPP(+) efflux. Additionally, we investigated mice that mimic a neurogenetic disease known as Angelman syndrome. These mice possess reduced αCaMKII activity. Angelman syndrome mice demonstrated an impaired DAT efflux function, which was comparable with that of the αCaMKII mutant mice, indicating that DAT-mediated dopaminergic signaling is affected in Angelman syndrome.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Amphetamine / pharmacology
  • Angelman Syndrome / genetics
  • Angelman Syndrome / metabolism*
  • Angelman Syndrome / pathology
  • Animals
  • Biological Transport, Active / drug effects
  • Biological Transport, Active / genetics
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / genetics
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism*
  • Cells, Cultured
  • Disease Models, Animal
  • Dopamine Agents / pharmacology
  • Dopamine Plasma Membrane Transport Proteins / genetics
  • Dopamine Plasma Membrane Transport Proteins / metabolism*
  • Dopaminergic Neurons / metabolism*
  • Dopaminergic Neurons / pathology
  • Humans
  • Mice
  • Mice, Knockout
  • Mutation, Missense
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Signal Transduction*

Substances

  • Dopamine Agents
  • Dopamine Plasma Membrane Transport Proteins
  • Nerve Tissue Proteins
  • Amphetamine
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2
  • Camk2a protein, mouse