Evidence for dimerization of dimers in K+ channel assembly

Biophys J. 1999 Apr;76(4):2004-17. doi: 10.1016/S0006-3495(99)77358-3.

Abstract

Voltage-gated K+ channels are tetrameric, but how the four subunits assemble is not known. We analyzed inactivation kinetics and peak current levels elicited for a variety of wild-type and mutant Kv1.3 subunits, expressed singly, in combination, and as tandem constructs, to show that 1) the dominant pathway involves a dimerization of dimers, and 2) dimer-dimer interaction may involve interaction sites that differ from those involved in monomer-monomer association. Moreover, using nondenaturing gel electrophoresis, we detected dimers and tetramers, but not trimers, in the translation reaction of Kv1.3 monomers.

Publication types

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

MeSH terms

  • Animals
  • Binding Sites
  • Biophysical Phenomena
  • Biophysics
  • Dimerization
  • Female
  • In Vitro Techniques
  • Kinetics
  • Membrane Potentials
  • Models, Biological
  • Mutation
  • Neuropeptides / chemistry*
  • Neuropeptides / genetics
  • Neuropeptides / metabolism*
  • Oocytes / metabolism
  • Potassium Channels / chemistry*
  • Potassium Channels / genetics
  • Potassium Channels / metabolism*
  • Potassium Channels, Voltage-Gated*
  • Protein Conformation
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Shaw Potassium Channels
  • Xenopus laevis

Substances

  • Neuropeptides
  • Potassium Channels
  • Potassium Channels, Voltage-Gated
  • Recombinant Proteins
  • Shaw Potassium Channels