|
|
|
|
|
|
|
||
The Journal of General Physiology, Vol 102, 977-1003, Copyright © 1993 by The Rockefeller University Press
ARTICLES |
RD Murrell-Lagnado and RW Aldrich
Howard Hughes Medical Institute, Department of Molecular and Cellular Physiology, Stanford University Medical Center, California 94305.
A synthetic peptide of the NH2-terminal inactivation domain of the ShB channel blocks Shaker channels which have an NH2-terminal deletion and mimics many of the characteristics of the intramolecular inactivation reaction. To investigate the role of electrostatic interactions in both peptide block and the inactivation process we measured the kinetics of block of macroscopic currents recorded from the intact ShB channel, and from ShB delta 6-46 channels in the presence of peptides, at different ionic strengths. The rate of inactivation and the association rate constants (k(on)) for the ShB peptides decreased with increasing ionic strength. k(on) for a more positively charged peptide was more steeply dependent on ionic strength consistent with a simple electrostatic mechanism of enhanced diffusion. This suggests that a rate limiting step in the inactivation process is the diffusion of the NH2-terminal domain towards the pore. The dissociation rates (k(off)) were insensitive to ionic strength. The temperature dependence of k(on) for the ShB peptide was very high, (Q10 = 5.0 +/- 0.58), whereas k(off) was relatively temperature insensitive (Q10 approximately 1.1). The results suggest that at higher temperatures the proportion of time either the peptide or channel spends in the correct conformation for binding is increased. There were two components to the time course of recovery from block by the ShB peptide, indicating two distinct blocked states, one of which has similar kinetics and dependence on external K+ concentration as the inactivated state of ShB. The other is voltage- dependent and at -120 mV is very unstable. Increasing the net charge on the peptide did not increase sensitivity to knock-off by external K+. We propose that the free peptide, having fewer constraints than the tethered NH2-terminal domain binds to a similar site on the channel in at least two different conformations.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  X.-D. Zhang, P.-Y. Tseng, W.-P. Yu, and T.-Y. Chen Blocking Pore-open Mutants of CLC-0 by Amphiphilic Blockers J. Gen. Physiol., December 29, 2008; 133(1): 43 - 58. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X.-D. Zhang and T.-Y. Chen Amphiphilic Blockers Punch through a Mutant CLC-0 Pore J. Gen. Physiol., December 29, 2008; 133(1): 59 - 68. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Panaghie, K. Purtell, K.-K. Tai, and G. W. Abbott Voltage-Dependent C-Type Inactivation in a Constitutively Open K+ Channel Biophys. J., September 15, 2008; 95(6): 2759 - 2778. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Barghaan, M. Tozakidou, H. Ehmke, and R. Bahring Role of N-Terminal Domain and Accessory Subunits in Controlling Deactivation-Inactivation Coupling of Kv4.2 Channels Biophys. J., February 15, 2008; 94(4): 1276 - 1294. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S.-Q. Cai and F. Sesti A New Mode of Regulation of N-type Inactivation in a Caenorhabditis elegans Voltage-gated Potassium Channel J. Biol. Chem., June 22, 2007; 282(25): 18597 - 18601. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Li, J. Yao, X. Tong, Z. Guo, Y. Wu, L. Sun, N. Pan, H. Wu, T. Xu, and J. Ding Interaction Sites between the Slo1 Pore and the NH2 Terminus of the beta2 Subunit, Probed with a Three-residue Sensor J. Biol. Chem., June 15, 2007; 282(24): 17720 - 17728. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Li and R. W. Aldrich State-dependent Block of BK Channels by Synthesized Shaker Ball Peptides J. Gen. Physiol., October 1, 2006; 128(4): 423 - 441. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. B. Long, E. B. Campbell, and R. MacKinnon Crystal Structure of a Mammalian Voltage-Dependent Shaker Family K+ Channel Science, August 5, 2005; 309(5736): 897 - 903. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. C. Mead and A. J. Williams Electrostatic Mechanisms Underlie Neomycin Block of the Cardiac Ryanodine Receptor Channel (RyR2) Biophys. J., December 1, 2004; 87(6): 3814 - 3825. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Brauchi, P. Orio, and R. Latorre Clues to understanding cold sensation: Thermodynamics and electrophysiological analysis of the cold receptor TRPM8 PNAS, October 26, 2004; 101(43): 15494 - 15499. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. A. Weihofen, J. Liu, W. Reutter, W. Saenger, and H. Fan Crystal Structure of CD26/Dipeptidyl-peptidase IV in Complex with Adenosine Deaminase Reveals a Highly Amphiphilic Interface J. Biol. Chem., October 8, 2004; 279(41): 43330 - 43335. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Z.-H. Zhang, K. J. Rhodes, W. E. Childers, T. M. Argentieri, and Q. Wang "Disinactivation" of N-type Inactivation of Voltage-gated K Channels by an Erbstatin Analogue J. Biol. Chem., July 9, 2004; 279(28): 29226 - 29230. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Zuniga, M. I. Niemeyer, D. Varela, M. Catalan, L. P. Cid, and F. V. Sepulveda The voltage-dependent ClC-2 chloride channel has a dual gating mechanism J. Physiol., March 15, 2004; 555(3): 671 - 682. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Gebauer, D. Isbrandt, K. Sauter, B. Callsen, A. Nolting, O. Pongs, and R. Bahring N-type Inactivation Features of Kv4.2 Channel Gating Biophys. J., January 1, 2004; 86(1): 210 - 223. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Liu, K. Hui, and F. Qin Thermodynamics of Heat Activation of Single Capsaicin Ion Channels VR1 Biophys. J., November 1, 2003; 85(5): 2988 - 3006. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Sukhareva, D. H. Hackos, and K. J. Swartz Constitutive Activation of the Shaker Kv Channel J. Gen. Physiol., October 27, 2003; 122(5): 541 - 556. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X.-M. Xia, J.P. Ding, and C. J. Lingle Inactivation of BK Channels by the NH2 Terminus of the {beta}2 Auxiliary Subunit: An Essential Role of a Terminal Peptide Segment of Three Hydrophobic Residues J. Gen. Physiol., February 3, 2003; 121(2): 125 - 148. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Holmgren Influence of Permeant Ions on Gating in Cyclic Nucleotide-gated Channels J. Gen. Physiol., December 30, 2002; 121(1): 61 - 72. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. J. Padanilam, T. Lu, T. Hoshi, B. A. Padanilam, E. F. Shibata, and H.-C. Lee Molecular Determinants of Intracellular pH Modulation of Human Kv1.4 N-Type Inactivation Mol. Pharmacol., July 1, 2002; 62(1): 127 - 134. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Wissmann, T. Baukrowitz, H. Kalbacher, H. R. Kalbitzer, J. P. Ruppersberg, O. Pongs, C. Antz, and B. Fakler NMR Structure and Functional Characteristics of the Hydrophilic N Terminus of the Potassium Channel beta -Subunit Kvbeta 1.1 J. Biol. Chem., December 10, 1999; 274(50): 35521 - 35525. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Avdonin, J. Kasuya, M. A. Ciorba, B. Kaplan, T. Hoshi, and L. Iverson Apoptotic proteins Reaper and Grim induce stable inactivation in voltage-gated K+ channels PNAS, September 29, 1998; 95(20): 11703 - 11708. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. A. Sullivan, M. H. Holmqvist, and I. B. Levitan Characterization of Gating and Peptide Block of mSlo, a Cloned Calcium-Dependent Potassium Channel J Neurophysiol, December 1, 1997; 78(6): 2937 - 2950. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C.-C. Kuo Deactivation Retards Recovery from Inactivation in Shaker K+ Channels J. Neurosci., May 15, 1997; 17(10): 3436 - 3444. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Kellenberger, T. Scheuer, and W. A. Catterall Movement of the Na+ Channel Inactivation Gate during Inactivation J. Biol. Chem., November 29, 1996; 271(48): 30971 - 30979. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. S. Ostedgaard, O. Baldursson, D. W. Vermeer, M. J. Welsh, and A. D. Robertson A functional R domain from cystic fibrosis transmembrane conductance regulator is predominantly unstructured in solution PNAS, May 9, 2000; 97(10): 5657 - 5662. [Abstract] [Full Text] [PDF]
|
|
|
|
