Referenced in: none

Automatically associated channels: Kir6.2

Title: Molecular basis for K(ATP) assembly: transmembrane interactions mediate association of a K+ channel with an ABC transporter.

Authors: B Schwappach, N Zerangue, Y N Jan, L Y Jan

Journal, date & volume: Neuron, 2000 Apr , 26, 155-67

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/10798400

Abstract
K(ATP) channels are large heteromultimeric complexes containing four subunits from the inwardly rectifying K+ channel family (Kir6.2) and four regulatory sulphonylurea receptor subunits from the ATP-binding cassette (ABC) transporter family (SUR1 and SUR2A/B). The molecular basis for interactions between these two unrelated protein families is poorly understood. Using novel trafficking-based interaction assays, coimmunoprecipitation, and current measurements, we show that the first transmembrane segment (M1) and the N terminus of Kir6.2 are involved in K(ATP) assembly and gating. Additionally, the transmembrane domains, but not the nucleotide-binding domains, of SUR1 are required for interaction with Kir6.2. The identification of specific transmembrane interactions involved in K(ATP) assembly may provide a clue as to how ABC proteins that transport hydrophobic substrates evolved to regulate other membrane proteins.