Publication
Title
Properties of deactivation gating currents in shaker channels
Author
Abstract
The charge versus voltage relation of voltage-sensor domains shifts in the voltage axis depending on the initial voltage. Here we show that in nonconducting W434F Shaker K+ channels, a large portion of this charge-voltage shift is apparent due to a dramatic slowing of the deactivation gating currents, IgD (with τ up to 80 ms), which develops with a time course of not, vert, similar1.8 s. This slowing in IgD adds up to the slowing due to pore opening and is absent in the presence of 4-aminopyridine, a compound that prevents the last gating step that leads to pore opening. A remaining 1015 mV negative shift in the voltage dependence of both the kinetics and the charge movement persists independently of the depolarizing prepulse duration and remains in the presence of 4-aminopyridine, suggesting the existence of an intrinsic offset in the local electric field seen by activated channels. We propose a new (to our knowledge) kinetic model that accounts for these observations.
Language
English
Source (journal)
Biophysical journal. - New York, N.Y.
Publication
New York, N.Y. : 2011
ISSN
0006-3495
Volume/pages
100:5(2011), p. L28-L30
ISI
000288049400002
Full text (Publisher's DOI)
Full text (open access)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 12.05.2011
Last edited 04.11.2017
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