Distinct roles for spinophilin and neurabin in dopamine-mediated plasticity

Neuroscience. 2006 Jul 7;140(3):897-911. doi: 10.1016/j.neuroscience.2006.02.067.


Protein phosphatase 1 plays a major role in the governance of excitatory synaptic activity, and is subject to control via the neuromodulatory actions of dopamine. Mechanisms involved in regulating protein phosphatase 1 activity include interactions with the structurally related cytoskeletal elements spinophilin and neurabin, synaptic scaffolding proteins that are highly enriched in dendritic spines. The requirement for these proteins in dopamine-related neuromodulation was tested using knockout mice. Dopamine D1-mediated regulation of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor activity was deficient in both striatal and prefrontal cortical neurons from neurabin knockout mice; in spinophilin knockout mice this deficit was manifest only in striatal neurons. At corticostriatal synapses long-term potentiation was deficient in neurabin knockout mice, but not in spinophilin knockout mice, and was rescued by a D1 receptor agonist. In contrast, long-term depression was deficient in spinophilin knockout mice but not in neurabin knockout mice, and was rescued by D2 receptor activation. Spontaneous excitatory post-synaptic current frequency was increased in neurabin knockout mice, but not in spinophilin knockout mice, and this effect was normalized by D2 receptor agonist application. Both knockout strains displayed increased induction of GluR1 Ser(845) phosphorylation in response to D1 receptor stimulation in slices, and also displayed enhanced locomotor activation in response to cocaine administration. These effects could be dissociated from cocaine reward, which was enhanced only in spinophilin knockout mice, and was accompanied by increased immediate early gene induction. These data establish a requirement for synaptic scaffolding in dopamine-mediated responses, and further indicate that spinophilin and neurabin play distinct roles in dopaminergic signal transduction and psychostimulant response.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / metabolism*
  • Corpus Striatum / metabolism
  • Dendritic Spines / drug effects
  • Dendritic Spines / metabolism
  • Dopamine / metabolism*
  • Dopamine Agonists / pharmacology
  • Excitatory Postsynaptic Potentials / drug effects
  • Excitatory Postsynaptic Potentials / physiology
  • Long-Term Potentiation / genetics
  • Mice
  • Mice, Knockout
  • Microfilament Proteins / genetics*
  • Motor Activity / drug effects
  • Motor Activity / genetics
  • Nerve Tissue Proteins / genetics*
  • Neural Pathways / metabolism
  • Neuronal Plasticity / physiology*
  • Organ Culture Techniques
  • Patch-Clamp Techniques
  • Phosphoprotein Phosphatases / metabolism*
  • Prefrontal Cortex / metabolism
  • Protein Phosphatase 1
  • Receptors, AMPA / metabolism
  • Receptors, Dopamine D1 / agonists
  • Receptors, Dopamine D1 / metabolism
  • Receptors, Dopamine D2 / agonists
  • Receptors, Dopamine D2 / metabolism
  • Reward


  • Dopamine Agonists
  • Microfilament Proteins
  • Nerve Tissue Proteins
  • Receptors, AMPA
  • Receptors, Dopamine D1
  • Receptors, Dopamine D2
  • neurabin
  • Phosphoprotein Phosphatases
  • Protein Phosphatase 1
  • glutamate receptor ionotropic, AMPA 1
  • Dopamine