Identification of domains that control the heteromeric assembly of Kir5.1/Kir4.0 potassium channels.
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.
Konstas
Angelos-Aristeidis
AA
University Laboratory of Physiology, Oxford, OX1 3PT, United Kingdom.
Korbmacher
Christoph
C
Tucker
Stephen J
SJ
D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D005260:Female; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes; D015221:Potassium Channels / Q000235:genetics / Q000378:metabolism; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000502:physiology*; D017434:Protein Structure, Tertiary / Q000502:physiology; D051381:Rats; D014982:Xenopus laevis
C510693:Kcnj1 protein, mouse; C510692:Kcnj1 protein, rat; D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying