Striatin-1 is a B subunit of protein phosphatase PP2A that regulates dendritic arborization and spine development in striatal neurons

J Biol Chem. 2018 Jul 13;293(28):11179-11194. doi: 10.1074/jbc.RA117.001519. Epub 2018 May 25.


Striatin-1, a subunit of the serine/threonine phosphatase PP2A, is preferentially expressed in neurons in the striatum. As a member of the striatin family of B subunits, striatin-1 is a core component together with PP2A of a multiprotein complex called STRIPAK, the striatin-interacting phosphatase and kinase complex. Little is known about the function of striatin-1 or the STRIPAK complex in the mammalian striatum. Here, we identify a selective role for striatin-1 in striatal neuron maturation. Using a small hairpin RNA (shRNA) knockdown approach in primary striatal neuronal cultures, we determined that reduced expression of striatin-1 results in increased dendritic complexity and an increased density of dendritic spines, classified as stubby spines. The dendritic phenotype was rescued by co-expression of a striatin-1 mutant construct insensitive to the knockdown shRNA but was not rescued by co-expression of PP2A- or Mob3-binding deficient striatin-1 constructs. Reduction of striatin-1 did not result in deficits in neuronal connectivity in this knockdown model, as we observed no abnormalities in synapse formation or in spontaneous excitatory postsynaptic currents. Thus, this study suggests that striatin-1 is a regulator of neuronal development in striatal neurons.

Keywords: STRIPAK; dendrite; dendritic spine; neurodevelopment; protein phosphatase 2 (PP2A); signal transduction; striatin-1.

Publication types

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

MeSH terms

  • Animals
  • Calmodulin-Binding Proteins / genetics
  • Calmodulin-Binding Proteins / metabolism*
  • Cells, Cultured
  • Female
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Multiprotein Complexes / genetics
  • Multiprotein Complexes / metabolism*
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Neuronal Plasticity
  • Neurons / cytology*
  • Neurons / metabolism
  • Protein Phosphatase 2 / genetics
  • Protein Phosphatase 2 / metabolism*
  • Protein Subunits
  • Rats
  • Rats, Sprague-Dawley
  • Spine / cytology*
  • Spine / metabolism*


  • Calmodulin-Binding Proteins
  • Membrane Proteins
  • Multiprotein Complexes
  • Nerve Tissue Proteins
  • Protein Subunits
  • Strn protein, mouse
  • Protein Phosphatase 2