Role of Septin cytoskeleton in spine morphogenesis and dendrite development in neurons

Curr Biol. 2007 Oct 23;17(20):1752-8. doi: 10.1016/j.cub.2007.09.039. Epub 2007 Oct 11.


Septins are GTP-binding proteins that polymerize into heteromeric filaments and form microscopic bundles or ring structures in vitro and in vivo. Because of these properties and their ability to associate with membrane, F-actin, and microtubules, septins have been generally regarded as cytoskeletal components [1, 2]. Septins are known to play roles in cytokinesis, in membrane trafficking, and as structural scaffolds; however, their function in neurons is poorly understood. Many members of the septin family, including Septin 7 (Sept7), were found by mass-spectrometry analysis of postsynaptic density (PSD) fractions of the brain [3, 4], suggesting a possible postsynaptic function of septins in neurons. We report that Sept7 is localized at the base of dendritic protrusions and at dendritic branch points in cultured hippocampal neurons--a distribution reminiscent of septin localization in the bud neck of budding yeast. Overexpression of Sept7 increased dendrite branching and the density of dendritic protrusions, whereas RNA interference (RNAi)-mediated knockdown of Sept7 led to reduced dendrite arborization and a greater proportion of immature protrusions. These data suggest that Sept7 is critical for spine morphogenesis and dendrite development during neuronal maturation.

Publication types

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

MeSH terms

  • Animals
  • Brain / cytology
  • Brain / metabolism
  • Cells, Cultured
  • Cytoskeletal Proteins / antagonists & inhibitors
  • Cytoskeletal Proteins / genetics
  • Cytoskeletal Proteins / metabolism*
  • Dendrites / metabolism*
  • Dendrites / ultrastructure
  • GTP-Binding Proteins / antagonists & inhibitors
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism*
  • Hippocampus / cytology
  • Hippocampus / metabolism
  • Neurons / metabolism*
  • Neurons / ultrastructure*
  • RNA Interference
  • Rats
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Transfection


  • Cytoskeletal Proteins
  • Recombinant Proteins
  • GTP-Binding Proteins