Title: PKC and AMPK regulation of Kv1.5 potassium channels.

Authors: Martin Nybo Andersen, Lasse Skibsbye, Chuyi Tang, Frederic Petersen, Nanna MacAulay, Hanne Borger Rasmussen, Thomas Jespersen

Journal, date & volume: Channels (Austin), 2015 , 9, 121-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/26043299

Abstract
The voltage-gated Kv1.5 potassium channel, conducting the ultra-rapid rectifier K(+) current (IKur), is regulated through several pathways. Here we investigate if Kv1.5 surface expression is controlled by the 2 kinases PKC and AMPK, using Xenopus oocytes, MDCK cells and atrial derived HL-1 cells. By confocal microscopy combined with electrophysiology we demonstrate that PKC activation reduces Kv1.5 current, through a decrease in membrane expressed channels. AMPK activation was found to decrease the membrane expression in MDCK cells, but not in HL-1 cells and was furthermore shown to be dependent on co-expression of Nedd4-2 in Xenopus oocytes. These results indicate that Kv1.5 channels are regulated by both kinases, although through different molecular mechanisms in different cell systems.