Skip to main content
placeholder image

Open-state stabilization in Kv channels: Voltage-sensor relaxation and pore propping by a bound ion

Journal Article


Abstract


  • Historical context and overview

    The Hodgkin and Huxley (1952) description of Na and

    K conductances underlying the action potential in

    squid giant axon is remarkable not only for its predictive accuracy in describing the shape and propagation

    velocity of the action potential but also for its foresight.

    Within their quantitative analysis and meticulous discussion are the seeds of decades of subsequent study,

    including the recognition that the ion-selective conductances must be provided by a relatively small number of

    highly conductive sites, which we now know as ion channels. Further, they concluded that, hidden in the electrical noise of their records, was a smaller, transient

    current that represented the movement of voltagesensing charges within the membrane. Those “gating

    currents” were first reported by Armstrong and Bezanilla

    (1973) and reflect the movement of voltage-sensor

    charges in response to changes in the electric field, providing voltage sensitivity to the opening and closing of

    gates, which switch the channels between resting and

    conducting states. Stability of open/activated states

    under different conditions is most directly evaluated in

    macroscopic voltage-clamp recordings of the kinetics of

    ionic current deactivation (Ideac, reflecting channel closure), and the return of gating charge to its resting position (IgOFF) during a repolarizing voltage step applied

    after activation.

Publication Date


  • 2012

Geographic Focus


Citation


  • French, R. J. & Finol Urdaneta, R. K. (2012). Open-state stabilization in Kv channels: Voltage-sensor relaxation and pore propping by a bound ion. Journal of General Physiology, 140 (5), 463-467.

Scopus Eid


  • 2-s2.0-84870848088

Has Global Citation Frequency


Number Of Pages


  • 4

Start Page


  • 463

End Page


  • 467

Volume


  • 140

Issue


  • 5

Place Of Publication


  • United States

Abstract


  • Historical context and overview

    The Hodgkin and Huxley (1952) description of Na and

    K conductances underlying the action potential in

    squid giant axon is remarkable not only for its predictive accuracy in describing the shape and propagation

    velocity of the action potential but also for its foresight.

    Within their quantitative analysis and meticulous discussion are the seeds of decades of subsequent study,

    including the recognition that the ion-selective conductances must be provided by a relatively small number of

    highly conductive sites, which we now know as ion channels. Further, they concluded that, hidden in the electrical noise of their records, was a smaller, transient

    current that represented the movement of voltagesensing charges within the membrane. Those “gating

    currents” were first reported by Armstrong and Bezanilla

    (1973) and reflect the movement of voltage-sensor

    charges in response to changes in the electric field, providing voltage sensitivity to the opening and closing of

    gates, which switch the channels between resting and

    conducting states. Stability of open/activated states

    under different conditions is most directly evaluated in

    macroscopic voltage-clamp recordings of the kinetics of

    ionic current deactivation (Ideac, reflecting channel closure), and the return of gating charge to its resting position (IgOFF) during a repolarizing voltage step applied

    after activation.

Publication Date


  • 2012

Geographic Focus


Citation


  • French, R. J. & Finol Urdaneta, R. K. (2012). Open-state stabilization in Kv channels: Voltage-sensor relaxation and pore propping by a bound ion. Journal of General Physiology, 140 (5), 463-467.

Scopus Eid


  • 2-s2.0-84870848088

Has Global Citation Frequency


Number Of Pages


  • 4

Start Page


  • 463

End Page


  • 467

Volume


  • 140

Issue


  • 5

Place Of Publication


  • United States