Ultrastructure of the 5-hydroxytryptamine3 receptor

J Neurochem. 1995 Mar;64(3):1401-5. doi: 10.1046/j.1471-4159.1995.64031401.x.


We have determined the ultrastructure of 5-hydroxytryptamine3 (5-HT3) serotonin receptors purified from NG108-15 mouse neuroblastoma x rat glioma cells by electron microscopic examination of receptor particles embedded in uranyl acetate stain and metal replicas of rapidly frozen receptors. The 5-HT3 receptor can be modelled as a cylinder 11 nm in length and 8 nm in diameter with a closed end and a central cavity 3 nm in diameter. Analysis of the rotational symmetry of single receptor particles indicates that the 5-HT3 receptor is composed of five subunits arranged symmetrically around a central cavity. Together with evidence obtained for related proteins in other studies using ultrastructural, biochemical, or electrophysiological methods, our observations suggest that all members of the ligand-gated ion channel superfamily may possess a pentameric quaternary structure.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Hybrid Cells
  • Ion Channel Gating
  • Mice
  • Microscopy, Electron
  • Protein Conformation
  • Rats
  • Receptors, Serotonin / ultrastructure*


  • Receptors, Serotonin