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Fast and slow gating are inherent properties of the pore module of the K+ channel Kcv.

Abenavoli, Alessandra ; DiFrancesco, Mattia Lorenzo ; Schroeder, Indra ; Epimashko, Svetlana ; Gazzarrini, Sabrina ; Hansen, Ulf Peter ; Thiel, Gerhard ; Moroni, Anna :
Fast and slow gating are inherent properties of the pore module of the K+ channel Kcv.
In: The Journal of general physiology, 134 (3) pp. 219-29. ISSN 1540-7748
[Artikel], (2009)

Kurzbeschreibung (Abstract)

Kcv from the chlorella virus PBCV-1 is a viral protein that forms a tetrameric, functional K+ channel in heterologous systems. Kcv can serve as a model system to study and manipulate basic properties of the K+ channel pore because its minimalistic structure (94 amino acids) produces basic features of ion channels, such as selectivity, gating, and sensitivity to blockers. We present a characterization of Kcv properties at the single-channel level. In symmetric 100 mM K+, single-channel conductance is 114+/-11 pS. Two different voltage-dependent mechanisms are responsible for the gating of Kcv. "Fast" gating, analyzed by beta distributions, is responsible for the negative slope conductance in the single-channel current-voltage curve at extreme potentials, like in MaxiK potassium channels, and can be explained by depletion-aggravated instability of the filter region. The presence of a "slow" gating is revealed by the very low (in the order of 1-4%) mean open probability that is voltage dependent and underlies the time-dependent component of the macroscopic current.

Typ des Eintrags: Artikel
Erschienen: 2009
Autor(en): Abenavoli, Alessandra ; DiFrancesco, Mattia Lorenzo ; Schroeder, Indra ; Epimashko, Svetlana ; Gazzarrini, Sabrina ; Hansen, Ulf Peter ; Thiel, Gerhard ; Moroni, Anna
Titel: Fast and slow gating are inherent properties of the pore module of the K+ channel Kcv.
Sprache: Englisch
Kurzbeschreibung (Abstract):

Kcv from the chlorella virus PBCV-1 is a viral protein that forms a tetrameric, functional K+ channel in heterologous systems. Kcv can serve as a model system to study and manipulate basic properties of the K+ channel pore because its minimalistic structure (94 amino acids) produces basic features of ion channels, such as selectivity, gating, and sensitivity to blockers. We present a characterization of Kcv properties at the single-channel level. In symmetric 100 mM K+, single-channel conductance is 114+/-11 pS. Two different voltage-dependent mechanisms are responsible for the gating of Kcv. "Fast" gating, analyzed by beta distributions, is responsible for the negative slope conductance in the single-channel current-voltage curve at extreme potentials, like in MaxiK potassium channels, and can be explained by depletion-aggravated instability of the filter region. The presence of a "slow" gating is revealed by the very low (in the order of 1-4%) mean open probability that is voltage dependent and underlies the time-dependent component of the macroscopic current.

Titel der Zeitschrift, Zeitung oder Schriftenreihe: The Journal of general physiology
Band: 134
(Heft-)Nummer: 3
Fachbereich(e)/-gebiet(e): Fachbereich Biologie, Biology > Membranbiophysik der Pflanzen, Plant Membrane Biophysics
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Fachbereich Biologie, Biology
Hinterlegungsdatum: 21 Jun 2011 11:59
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