Multiple sites of interaction between the intracellular domains of an inwardly rectifying potassium channel, Kir6.2.

Journal article

The amino-terminal and carboxy-terminal domains of inwardly rectifying potassium channel (Kir) subunits are both intracellular. A direct physical interaction between these two domains is involved in the response of Kir channels to regulatory factors such as G-proteins, nucleotides and intracellular pH. We have previously mapped the region within the N-terminal domain of Kir6.2 that interacts with the C-terminus. In this study we use a similar in vitro protein-protein interaction assay to map the regions within the C-terminus which interact with the N-terminus. We find that multiple interaction domains exist within the C-terminus: CID1 (amino acids (aa) 279-323), CID2 (aa 214-222) and CID3 (aa 170-204). These domains correlate with regions previously identified as making important contributions to Kir channel assembly and function. The highly conserved nature of the C-terminus suggests that a similar association with the N-terminus may be a feature common to all members of the Kir family of potassium channels, and that it may be involved in gating of Kir channels by intracellular ligands.

Authors: Jones, P; Tucker, S; Ashcroft, F

• Publication status: Published
• Journal: FEBS letters
• Volume: 508
• Issue: 1
• Pages: 85-89
• Publication date: 2001-11-01
• DOI: 10.1016/s0014-5793(01)03023-x
• EISSN: 1873-3468
• ISSN: 0014-5793
• Language: English
• Keywords: Molecular Sequence Data; Potassium Channels, Inwardly Rectifying; Protein Structure, Tertiary; Sequence Alignment; Protein Binding; Recombinant Fusion Proteins; Amino Acid Sequence