Alteration and restoration of K+ channel function by deletions at the N- and C-termini

Neuron. 1990 Oct;5(4):433-43. doi: 10.1016/0896-6273(90)90082-q.


Voltage-dependent ion channels are thought to consist of a highly conserved repeated core of six transmembrane segments, flanked by more variable cytoplasmic domains. Significant functional differences exist among related types of K+ channels. These differences have been attributed to the variable domains, most prominently the N- and C-termini. We have therefore investigated the functional importance of both termini for the delayed rectifier K+ channel from rat brain encoded by the drk1 gene. This channel has an unusually long C-terminus. Deletions in either terminus affected both activation and inactivation, in some cases profoundly. Unexpectedly, more extensive deletions in both termini restored gating. We could therefore define a core region only slightly longer than the six transmembrane segments that is sufficient for the formation of channels with the kinetics of a delayed rectifier.

Publication types

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

MeSH terms

  • Animals
  • Brain / metabolism*
  • Chromosome Deletion*
  • Electrophysiology
  • Ion Channel Gating
  • Kinetics
  • Mutation
  • Potassium Channels / genetics
  • Potassium Channels / metabolism*
  • Potassium Channels / physiology
  • Rats


  • Potassium Channels