Different effects of the Ca(2+)-binding protein, KChIP1, on two Kv4 subfamily members, Kv4.1 and Kv4.2

FEBS Lett. 2001 Jun 22;499(3):205-9. doi: 10.1016/s0014-5793(01)02560-1.

Abstract

The Ca(2+)-binding protein, K(+) channel-interacting protein 1 (KChIP1), modulates Kv4 channels. We show here that KChIP1 affects Kv4.1 and Kv4.2 currents differently. KChIP1 slows Kv4.2 inactivation but accelerates the Kv4.1 inactivation time course. Kv4.2 activation is shifted in a hyperpolarizing direction, whereas a depolarizing shift occurs for Kv4.1. On the other hand, KChIP1 increases the current amplitudes and accelerates recovery from inactivation of both currents. An involvement of the Kv4 N-terminus in these differential effects is demonstrated using chimeras of Kv4.2 and Kv4.1. These results reveal a novel interaction of KChIP1 with these two Kv4 members. This represents a mechanism to further increase the functional diversity of K(+) channels.

Publication types

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

MeSH terms

  • Animals
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / physiology*
  • Electrophysiology
  • Kv Channel-Interacting Proteins
  • Oocytes / physiology
  • Potassium Channels / physiology*
  • Potassium Channels, Voltage-Gated*
  • Shal Potassium Channels
  • Transfection
  • Xenopus laevis

Substances

  • Calcium-Binding Proteins
  • KCND1 protein, human
  • Kv Channel-Interacting Proteins
  • Potassium Channels
  • Potassium Channels, Voltage-Gated
  • Shal Potassium Channels