Identification of domains that control the heteromeric assembly of Kir5.1/Kir4.0 potassium channels

Am J Physiol Cell Physiol. 2003 Apr;284(4):C910-7. doi: 10.1152/ajpcell.00479.2002. Epub 2002 Nov 27.

Abstract

Heteromultimerization between different inwardly rectifying (Kir) potassium channel subunits is an important mechanism for the generation of functional diversity. However, little is known about the mechanisms that control this process and that prevent promiscuous interactions in cells that express many different Kir subunits. In this study, we have examined the heteromeric assembly of Kir5.1 with other Kir subunits and have shown that this subunit exhibits a highly selective interaction with members of the Kir4.0 subfamily and does not physically associate with other Kir subunits such as Kir1.1, Kir2.1, and Kir6.2. Furthermore, we have identified regions within the Kir4.1 subunit that appear to govern the specificity of this interaction. These results help us to understand the mechanisms that control Kir subunit recognition and assembly and how cells can express many different Kir channels while maintaining distinct subpopulations of homo- and heteromeric channels within the cell.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence / genetics
  • Animals
  • Female
  • Mice
  • Molecular Sequence Data
  • Oocytes
  • Potassium Channels / genetics
  • Potassium Channels / metabolism
  • Potassium Channels, Inwardly Rectifying / genetics
  • Potassium Channels, Inwardly Rectifying / metabolism*
  • Protein Processing, Post-Translational / physiology*
  • Protein Structure, Tertiary / physiology
  • Rats
  • Xenopus laevis

Substances

  • Kcnj1 protein, mouse
  • Kcnj1 protein, rat
  • Potassium Channels
  • Potassium Channels, Inwardly Rectifying