Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 21 July 1995:
Vol. 269. no. 5222, pp. 410 - 412
DOI: 10.1126/science.7618108
Prev | Table of Contents | Next

Articles

Science, Vol 269, Issue 5222, 410-412
Copyright © 1995 by American Association for the Advancement of Science

articles

Permeation selectivity by competition in a delayed rectifier potassium channel

SJ Korn and Ikeda SR

Department of Physiology and Neurobiology, University of Connecticut, Storrs 06269, USA.

Permeation selectivity was studied in two human potassium channels, Kv2.1 and Kv1.5, expressed in a mouse cell line. With normal concentrations of potassium and sodium, both channels were highly selective for potassium. On removal of potassium, Kv2.1 displayed a large sodium conductance that was inhibited by low concentrations of potassium. The channel showed a competition mechanism of selectivity similar to that of calcium channels. In contrast, Kv1.5 displayed a negligible sodium conductance on removal of potassium. The observation that structurally similar potassium channels show different abilities to conduct sodium provides a basis for understanding the structural determinants of potassium channel selectivity.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Futile Na+ cycling at the root plasma membrane in rice (Oryza sativa L.): kinetics, energetics, and relationship to salinity tolerance.
P. Malagoli, D. T. Britto, L. M. Schulze, and H. J. Kronzucker (2008)
J. Exp. Bot. 59, 4109-4117
   Abstract »    Full Text »    PDF »
Linkage between 'disruption of inactivation' and 'reduction of K+ selectivity' among hERG mutants in the S5-P linker region.
G.-N. Tseng (2006)
J. Physiol. 577, 459-460
   Full Text »    PDF »
Na+ Permeation and Block of hERG Potassium Channels.
H. Gang and S. Zhang (2006)
J. Gen. Physiol. 128, 55-71
   Abstract »    Full Text »    PDF »
Functional Role and Affinity of Inorganic Cations in Stabilizing the Tetrameric Structure of the KcsA K+ Channel.
M. N. Krishnan, J.-P. Bingham, S. H. Lee, P. Trombley, and E. Moczydlowski (2005)
J. Gen. Physiol. 126, 271-283
   Abstract »    Full Text »    PDF »
Two Stable, Conducting Conformations of the Selectivity Filter in Shaker K+ Channels.
J. Thompson and T. Begenisich (2005)
J. Gen. Physiol. 125, 619-629
   Abstract »    Full Text »    PDF »
K channel gating by an affinity-switching selectivity filter.
A. M. J. VanDongen (2004)
PNAS 101, 3248-3252
   Abstract »    Full Text »    PDF »
Molecular Basis of Ion Selectivity, Block, and Rectification of the Inward Rectifier Kir3.1/Kir3.4 K+ Channel.
K. M. Dibb, T. Rose, S. Y. Makary, T. W. Claydon, D. Enkvetchakul, R. Leach, C. G. Nichols, and M. R. Boyett (2003)
J. Biol. Chem. 278, 49537-49548
   Abstract »    Full Text »    PDF »
Influence of Pore Residues on Permeation Properties in the Kv2.1 Potassium Channel. Evidence for a Selective Functional Interaction of K+ with the Outer Vestibule.
J. F. Consiglio, P. Andalib, and S. J. Korn (2003)
J. Gen. Physiol. 121, 111-124
   Abstract »    Full Text »    PDF »
Control of Outer Vestibule Dynamics and Current Magnitude in the Kv2.1 Potassium Channel.
P. Andalib, M. J. Wood, and S. J. Korn (2002)
J. Gen. Physiol. 120, 739-755
   Abstract »    Full Text »    PDF »
Extracellular Sodium Interacts with the HERG Channel at an Outer Pore Site.
F. M. Mullins, S. Z. Stepanovic, R. R. Desai, A. L. George Jr., and J. R. Balser (2002)
J. Gen. Physiol. 120, 517-537
   Abstract »    Full Text »    PDF »
Cations Affect the Rate of Gating Charge Recovery in Wild-type and W434F Shaker Channels through a Variety of Mechanisms.
Z. Varga, M. D. Rayner, and J. G. Starkus (2002)
J. Gen. Physiol. 119, 467-486
   Abstract »    Full Text »    PDF »
Molecular identification of a TTX-sensitive Ca2+ current.
S. Guatimosim, E. A. Sobie, J. dos Santos Cruz, L. A. Martin, and W. J. Lederer (2001)
Am J Physiol Cell Physiol 280, C1327-C1339
   Abstract »    Full Text »    PDF »
Potassium inhibition of sodium-activated potassium (KNa) channels in guinea-pig ventricular myocytes.
X W Niu and R W Meech (2000)
J. Physiol. 526, 81-90
   Abstract »    Full Text »    PDF »
Regulation of transient Na+ conductance by intra- and extracellular K+ in the human delayed rectifier K+ channel Kv1.5.
Z. Wang, X. Zhang, and D. Fedida (2000)
J. Physiol. 523, 575-591
   Abstract »    Full Text »    PDF »
Characterization of the cloned human intermediate-conductance Ca2+-activated K+ channel.
B. S. Jensen, D. Strobak, P. Christophersen, T. D. Jorgensen, C. Hansen, A. Silahtaroglu, S.-P. Olesen, and P. K. Ahring (1998)
Am J Physiol Cell Physiol 275, C848-C856
   Abstract »    Full Text »    PDF »
Killing K Channels with TEA+.
K. Khodakhah, A. Melishchuk, and C. M. Armstrong (1997)
PNAS 94, 13335-13338
   Abstract »    Full Text »    PDF »
Cations Affect the Rate of Gating Charge Recovery in Wild-type and W434F Shaker Channels through a Variety of Mechanisms.
Z. Varga, M. D. Rayner, and J. G. Starkus (2002)
J. Gen. Physiol. 119, 467-486
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)