| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Biophys J, June 2001, p. 2678-2693, Vol. 80, No. 6
Department of Medicine, University of Ottawa, Neurosciences, Ottawa Health Research Institute, The Ottawa Hospital, Ottawa, Ontario K1Y 4K9, Canada
Mechanosensitive (MS) ion channels are ubiquitous in
eukaryotic cell types but baffling because of their contentious
physiologies and diverse molecular identities. In some cellular
contexts mechanically responsive ion channels are undoubtedly
mechanosensory transducers, but it does not follow that all MS channels
are mechanotransducers. Here we demonstrate, for an archetypical
voltage-gated channel (Shaker-IR; inactivation-removed),
robust MS channel behavior. In oocyte patches subjected to stretch,
Shaker-IR exhibits both stretch-activation (SA) and
stretch-inactivation (SI). SA is seen when prestretch
Popen (set by voltage) is low, and SI is
seen when it is high. The stretch effects occur in cell-attached and excised patches at both macroscopic and single-channel levels. Were one
ignorant of this particular MS channel's identity, one might propose
it had been designed as a sophisticated reporter of bilayer tension.
Knowing Shaker-IR's provenance and biology, however,
such a suggestion would be absurd. We argue that the MS responses of
Shaker-IR reflect not overlooked "mechano-gating" specializations of Shaker, but a common property of
multiconformation membrane proteins: inherent susceptibility to bilayer
tension. The molecular diversity of MS channels indicates that
susceptibility to bilayer tension is hard to design out of dynamic
membrane proteins. Presumably the cost of being insusceptible to
bilayer tension often outweighs the benefits, especially where the in
situ milieu of channels can provide mechanoprotection.
Biophys J, June 2001, p. 2678-2693, Vol. 80, No. 6
© 2001 by the Biophysical Society 0006-3495/01/06/2678/16 $2.00
This article has been cited by other articles:
 |
|
 |
|
  J. P. Reeves, M. Abdellatif, and M. Condrescu The sodium-calcium exchanger is a mechanosensitive transporter J. Physiol., March 15, 2008; 586(6): 1549 - 1563. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. E. Morris and P. F. Juranka Nav Channel Mechanosensitivity: Activation and Inactivation Accelerate Reversibly with Stretch Biophys. J., August 1, 2007; 93(3): 822 - 833. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. Lin, U. Laitko, P. F. Juranka, and C. E. Morris Dual Stretch Responses of mHCN2 Pacemaker Channels: Accelerated Activation, Accelerated Deactivation Biophys. J., March 1, 2007; 92(5): 1559 - 1572. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Nomura, M. Sokabe, and K. Yoshimura Lipid-Protein Interaction of the MscS Mechanosensitive Channel Examined by Scanning Mutagenesis Biophys. J., October 15, 2006; 91(8): 2874 - 2881. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 U. Laitko, P. F. Juranka, and C. E. Morris Membrane Stretch Slows the Concerted Step prior to Opening in a Kv Channel J. Gen. Physiol., May 30, 2006; 127(6): 687 - 701. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Bao, F. Sachs, and G. Dahl Connexins are mechanosensitive Am J Physiol Cell Physiol, November 1, 2004; 287(5): C1389 - C1395. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. J. Benos Sensing Tension: Recognizing ENaC as a Stretch Sensor Hypertension, November 1, 2004; 44(5): 616 - 617. [Full Text] [PDF]
|
|
|
|
 |
|
 B. Martinac Mechanosensitive ion channels: molecules of mechanotransduction J. Cell Sci., May 15, 2004; 117(12): 2449 - 2460. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Lundbaek, P. Birn, A. J. Hansen, R. Sogaard, C. Nielsen, J. Girshman, M. J. Bruno, S. E. Tape, J. Egebjerg, D. V. Greathouse, et al. Regulation of Sodium Channel Function by Bilayer Elasticity: The Importance of Hydrophobic Coupling. Effects of Micelle-forming Amphiphiles and Cholesterol J. Gen. Physiol., April 26, 2004; 123(5): 599 - 621. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
U. Laitko and C. E. Morris Membrane Tension Accelerates Rate-limiting Voltage-dependent Activation and Slow Inactivation Steps in a Shaker Channel J. Gen. Physiol., January 26, 2004; 123(2): 135 - 154. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Gullingsrud and K. Schulten Gating of MscL Studied by Steered Molecular Dynamics Biophys. J., October 1, 2003; 85(4): 2087 - 2099. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. A. Maurer and D. A. Dougherty Generation and Evaluation of a Large Mutational Library from the Escherichia coli Mechanosensitive Channel of Large Conductance, MscL: IMPLICATIONS FOR CHANNEL GATING AND EVOLUTIONARY DESIGN J. Biol. Chem., May 30, 2003; 278(23): 21076 - 21082. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Ou, P. Strege, S. M. Miller, J. Makielski, M. Ackerman, S. J. Gibbons, and G. Farrugia Syntrophin gamma 2 Regulates SCN5A Gating by a PDZ Domain-mediated Interaction J. Biol. Chem., January 10, 2003; 278(3): 1915 - 1923. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Calabrese, I. V. Tabarean, P. Juranka, and C. E. Morris Mechanosensitivity of N-Type Calcium Channel Currents Biophys. J., November 1, 2002; 83(5): 2560 - 2574. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. KUMANOVICS, G. LEVIN, and P. BLOUNT Family ties of gated pores: evolution of the sensor module FASEB J, October 1, 2002; 16(12): 1623 - 1629. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. V. Tabarean and C. E. Morris Membrane Stretch Accelerates Activation and Slow Inactivation in Shaker Channels with S3-S4 Linker Deletions Biophys. J., June 1, 2002; 82(6): 2982 - 2994. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Martinac and O. P. Hamill Gramicidin A channels switch between stretch activation and stretch inactivation depending on bilayer thickness PNAS, March 19, 2002; (2002) 72632899. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Martinac and O. P. Hamill Gramicidin A channels switch between stretch activation and stretch inactivation depending on bilayer thickness PNAS, April 2, 2002; 99(7): 4308 - 4312. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
