Rapid intracellular TEA block of the KcsA potassium channel.
Intracellular tetraethylammonium (TEA) inhibition was studied at the single-channel level in the KcsA potassium channel reconstituted in planar lipid bilayers. TEA acts as a fast blocker (resulting in decreased current amplitude) with an affinity in the 75 mM range even at high bandwidth. Studies over a wide voltage range reveal that TEA block has a complex voltage-dependence that also depends on the ionic conditions. These observations are examined in the context of permeation models to extend our understanding of the coupling between permeant ions and TEA blockade.
Kutluay
Esin
E
Department of Biochemistry, Weill Graduate School of Medical Sciences, Cornell University, New York, New York 10021, USA.
Roux
Benoît
B
Heginbotham
Lise
L
D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000648:ultrastructure; D002462:Cell Membrane / Q000737:chemistry*; D003198:Computer Simulation; D007424:Intracellular Fluid / Q000737:chemistry*; D015640:Ion Channel Gating / Q000187:drug effects*; D008051:Lipid Bilayers / Q000737:chemistry*; D008567:Membranes, Artificial; D008956:Models, Chemical; D008958:Models, Molecular; D010539:Permeability / Q000187:drug effects; D016062:Porosity / Q000187:drug effects; D015221:Potassium Channels / Q000737:chemistry* / Q000648:ultrastructure; D013329:Structure-Activity Relationship; D019789:Tetraethylammonium / Q000737:chemistry*
D001426:Bacterial Proteins; D008051:Lipid Bilayers; D008567:Membranes, Artificial; D015221:Potassium Channels; C107790:prokaryotic potassium channel; D019789:Tetraethylammonium