Referenced in: none

Automatically associated channels: Kv1.5 , Kv2.1

Title: Permeation selectivity by competition in a delayed rectifier potassium channel.

Authors: S J Korn, S R Ikeda

Journal, date & volume: Science, 1995 Jul 21 , 269, 410-2

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/7618108

Abstract
Permeation selectivity was studied in two human potassium channels, Kv2.1 and Kv1.5, expressed in a mouse cell line. With normal concentrations of potassium and sodium, both channels were highly selective for potassium. On removal of potassium, Kv2.1 displayed a large sodium conductance that was inhibited by low concentrations of potassium. The channel showed a competition mechanism of selectivity similar to that of calcium channels. In contrast, Kv1.5 displayed a negligible sodium conductance on removal of potassium. The observation that structurally similar potassium channels show different abilities to conduct sodium provides a basis for understanding the structural determinants of potassium channel selectivity.