Referenced in: none

Automatically associated channels: K2P , TASK1 , TASK3

Title: Diacylglycerol mediates regulation of TASK potassium channels by Gq-coupled receptors.

Authors: Bettina U Wilke, Moritz Lindner, Lea Greifenberg, Alexandra Albus, Yannick Kronimus, Moritz Bünemann, Michael G Leitner, Dominik Oliver

Journal, date & volume: Nat Commun, 2014 , 5, 5540

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/25420509

Abstract
The two-pore domain potassium (K2P) channels TASK-1 (KCNK3) and TASK-3 (KCNK9) are important determinants of background K(+) conductance and membrane potential. TASK-1/3 activity is regulated by hormones and transmitters that act through G protein-coupled receptors (GPCR) signalling via G proteins of the Gαq/11 subclass. How the receptors inhibit channel activity has remained unclear. Here, we show that TASK-1 and -3 channels are gated by diacylglycerol (DAG). Receptor-initiated inhibition of TASK required the activity of phospholipase C, but neither depletion of the PLC substrate PI(4,5)P2 nor release of the downstream messengers IP3 and Ca(2+). Attenuation of cellular DAG transients by DAG kinase or lipase suppressed receptor-dependent inhibition, showing that the increase in cellular DAG-but not in downstream lipid metabolites-mediates channel inhibition. The findings identify DAG as the signal regulating TASK channels downstream of GPCRs and define a novel role for DAG that directly links cellular DAG dynamics to excitability.