Two-dimensional crystallization of the mouse serotonin 5-HT3A receptor

Micron. 2017 Jan:92:19-24. doi: 10.1016/j.micron.2016.10.004. Epub 2016 Oct 22.

Abstract

The mouse serotonin 5-HT3A receptor is a homo-pentameric ligand-gated ion channel (pLGIC) mediating fast excitatory neurotransmission in the central nervous system. The molecular mechanism of ion permeation of 5-HT3A receptors triggered by the neurotransmitter serotonin is not yet fully understood. The recent X-ray structure of the mouse serotonin 5-HT3A receptor in complex with a stabilizing nanobody revealed for the first time the entire structure of a mammalian pLGIC in detergent. Structural information of the receptor in a lipid bilayer however is still limited primarily due to the lack of 2D crystals of the receptor in a lipid bilayer. Here we present our results on the formation and improvement of diffracting 2D crystals of the mouse 5-HT3A by limited proteolysis and addition of conformational nanobodies.

Keywords: 2D crystals; 5-HT3 receptor; Electron crystallography; Nanobody; Pentameric ligand-gated ion channel.

MeSH terms

  • Animals
  • Cryoelectron Microscopy
  • Crystallization*
  • Crystallography
  • Imaging, Three-Dimensional
  • Mice
  • Models, Molecular
  • Molecular Conformation
  • Receptors, Serotonin, 5-HT3 / chemistry*
  • Receptors, Serotonin, 5-HT3 / ultrastructure
  • Single-Domain Antibodies

Substances

  • Receptors, Serotonin, 5-HT3
  • Single-Domain Antibodies