Referenced in: none

Automatically associated channels: Kir6.2

Title: Truncation of Kir6.2 produces ATP-sensitive K+ channels in the absence of the sulphonylurea receptor.

Authors: S J Tucker, F M Gribble, C Zhao, S Trapp, F M Ashcroft

Journal, date & volume: Nature, 1997 May 8 , 387, 179-83

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/9144288

Abstract
ATP-sensitive potassium channels (K-ATP channels) couple cell metabolism to electrical activity and are important in the physiology and pathophysiology of many tissues. In pancreatic beta-cells, K-ATP channels link changes in blood glucose concentration to insulin secretion. They are also the target for clinically important drugs such as sulphonylureas, which stimulate secretion, and the K+ channel opener diazoxide, which inhibits insulin release. Metabolic regulation of K-ATP channels is mediated by changes in intracellular ATP and Mg-ADP levels, which inhibit and activate the channel, respectively. The beta-cell K-ATP channel is a complex of two proteins: an inward-rectifier K+ channel subunit, Kir6.2, and the sulphonylurea receptor, SUR1. We show here that the primary site at which ATP acts to mediate K-ATP channel inhibition is located on Kir6.2, and that SUR1 is required for sensitivity to sulphonylureas and diazoxide and for activation by Mg-ADP.