Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Conformational Dynamics of Shaker-Type Kv1.1 Ion Channel in Open, Closed, and Two Mutated States

Conformational Dynamics of Shaker-Type Kv1.1 Ion Channel in Open, Closed, and Two Mutated States The dynamic properties of shaker-type Kv1.1 ion channel in its open, closed, & two mutated (E325D & V408A) states embedded in DPPC membrane have been investigated using all-atom force field-based MD simulation. Here, we represent the detailed channel stability, gating environment of charge-carrying residues, salt bridge interaction among the voltage-sensing domains (VSDs), movement of S4 helix, and ion conduction of pore. At positive potential, the S4 helix undergoes lateral fluctuations in accordance with their gating motions found in every model. During transition from closed to active state conformation, charged residues of S4 move “up” across the membrane with an average tilt angle difference of 24°, which is more consistent with the paddle model of channel gating. The E325D mutation at C-terminal end of S4–S5 helical linker leads the channel to a rapid activated state by pushing the gating charge residues upward beside the VSDs resulting in more prominent tilt of S4. Similarly in V408A mutant model, disruption of hydrophobic gate at S6 C-terminal end takes place, which causes the violation of channel-active conformation by bringing the C-terminal end of S4 to its corresponding resting state. The ion permeation is observed only in open-state conformation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

Conformational Dynamics of Shaker-Type Kv1.1 Ion Channel in Open, Closed, and Two Mutated States

Loading next page...
 
/lp/springer_journal/conformational-dynamics-of-shaker-type-kv1-1-ion-channel-in-open-00I0TPtbTq

References (75)

Publisher
Springer Journals
Copyright
Copyright © 2014 by Springer Science+Business Media New York
Subject
Life Sciences; Biochemistry, general; Human Physiology
ISSN
0022-2631
eISSN
1432-1424
DOI
10.1007/s00232-014-9764-7
pmid
25451198
Publisher site
See Article on Publisher Site

Abstract

The dynamic properties of shaker-type Kv1.1 ion channel in its open, closed, & two mutated (E325D & V408A) states embedded in DPPC membrane have been investigated using all-atom force field-based MD simulation. Here, we represent the detailed channel stability, gating environment of charge-carrying residues, salt bridge interaction among the voltage-sensing domains (VSDs), movement of S4 helix, and ion conduction of pore. At positive potential, the S4 helix undergoes lateral fluctuations in accordance with their gating motions found in every model. During transition from closed to active state conformation, charged residues of S4 move “up” across the membrane with an average tilt angle difference of 24°, which is more consistent with the paddle model of channel gating. The E325D mutation at C-terminal end of S4–S5 helical linker leads the channel to a rapid activated state by pushing the gating charge residues upward beside the VSDs resulting in more prominent tilt of S4. Similarly in V408A mutant model, disruption of hydrophobic gate at S6 C-terminal end takes place, which causes the violation of channel-active conformation by bringing the C-terminal end of S4 to its corresponding resting state. The ion permeation is observed only in open-state conformation.

Journal

The Journal of Membrane BiologySpringer Journals

Published: Dec 2, 2014

There are no references for this article.