Differential localization and regulation of stargazin-like protein, gamma-8 and stargazin in the plasma membrane of hippocampal and cortical neurons

Neurosci Res. 2006 May;55(1):45-53. doi: 10.1016/j.neures.2006.01.004. Epub 2006 Mar 3.


Transmembrane AMPA receptor regulatory proteins (TARPs), including stargazin/gamma-2, are associated with AMPA receptors and participate in their surface delivery and anchoring at the postsynaptic membrane. TARPs may also act as a positive modulator of the AMPA receptor ion channel function; however, little is known about other TARP members except for stargazin/gamma-2. We examined the synaptic localization of stargazin/gamma-2 and gamma-8 by immunoelectron microscopy and biochemical analysis. The analysis of sodium dodecyl sulfate-digested freeze-fracture replica labeling revealed that stargazin/gamma-2 was concentrated in the postsynaptic area, whereas gamma-8 was distributed both in synaptic and extra-synaptic plasma membranes of the hippocampal neuron. When a synaptic plasma membrane-enriched brain fraction was treated with Triton X-100 and separated by sucrose density gradient ultracentrifugation, a large proportion of NMDA receptor and stargazin/gamma-2 was accumulated in raft-enriched fractions, whereas AMPA receptor and gamma-8 were distributed in both the raft-enriched fractions and other Triton-insoluble fractions. Phosphorylation of stargazin/gamma-2 and gamma-8 was regulated by different sets of kinases and phosphatases in cultured cortical neurons. These results suggested that stargazin/gamma-2 and gamma-8 have distinct roles in postsynaptic membranes under the regulation of different intracellular signaling pathways.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western / methods
  • Calcium Channels* / classification
  • Calcium Channels* / metabolism
  • Calcium Channels* / ultrastructure
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism*
  • Cell Membrane / ultrastructure
  • Cells, Cultured
  • Cerebral Cortex / cytology*
  • Enzyme Inhibitors / pharmacology
  • Excitatory Amino Acid Agonists / pharmacology
  • Freeze Etching / methods
  • Gene Expression Regulation / drug effects
  • Gene Expression Regulation / physiology
  • Hippocampus / cytology*
  • Humans
  • Immunohistochemistry / methods
  • Male
  • Microscopy, Immunoelectron / methods
  • N-Methylaspartate / pharmacology
  • Neurons / drug effects
  • Neurons / metabolism
  • Neurons / ultrastructure*
  • Phosphorylation / drug effects
  • Rats
  • Rats, Sprague-Dawley


  • Calcium Channels
  • Enzyme Inhibitors
  • Excitatory Amino Acid Agonists
  • N-Methylaspartate