Acetylcholine receptor channel imaged in the open state

Nature. 1995 Jan 5;373(6509):37-43. doi: 10.1038/373037a0.


The structure of the open-channel form of the acetylcholine receptor has been determined from electron images of Torpedo ray postsynaptic membranes activated by brief (< 5 ms) mixing with droplets containing acetylcholine. Comparison with the closed-channel form shows that acetylcholine initiates small rotations of the subunits in the extracellular domain, which trigger a change in configuration of alpha-helices lining the membrane-spanning pore. The open pore tapers towards the intracellular membrane face, where it is shaped by a 'barrel' of alpha-helices having a pronounced right-handed twist.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetylcholine*
  • Animals
  • Ferritins
  • Freezing
  • Image Processing, Computer-Assisted
  • Ion Channel Gating
  • Ions
  • Permeability
  • Receptors, Nicotinic / ultrastructure*
  • Synaptic Membranes / ultrastructure
  • Torpedo


  • Ions
  • Receptors, Nicotinic
  • Ferritins
  • Acetylcholine