Gating Kinetics of Ca"-activated K+ Channels from Rat ... - Europe PMC

6 downloads 0 Views 2MB Size Report
activated K+ channel incorporated into planar phospholipid bilayers from a ..... of illustration, straight lines were drawn by eye and the mean dwell times, T,.
Gating Kinetics of Ca"-activated K+ Channels from Rat Muscle Incorporated into Planar Lipid Bilayers Evidence for Two Voltage-dependent Ca 2' Binding Reactions EDWARD MOCZYDLOWSKI and RAMON LATORRE From the Department of Physiology and Biophysics, Harvard Medical School, Boston, Massachusetts 02115 ABSTRACT The gating kinetics of a Cat'-activated K' channel from adult rat muscle plasma membrane are studied in artificial planar bilayers . Analysis of single-channel fluctuations distinguishes two Ca 2 '- and voltage-dependent processes : (a) short-lived channel closure (