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Proc Natl Acad Sci U S A
2003 Jun 24;10013:7611-5. doi: 10.1073/pnas.1332409100.
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Fast gating in the Shaker K+ channel and the energy landscape of activation.
Sigg D
,
Bezanilla F
,
Stefani E
.
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An early component of the gating current in Shaker K+ channels with a time constant of approximately 12 microsec has been recorded with a high-speed patch-clamp setup. This fast component was found to be part of the gating current associated with the opening and closing of the channel. With regard to an energy-landscape interpretation of protein kinetics, the voltage and temperature dependence of the fast component may be explained by a combination of drift diffusion and barrier jumping in the initial stages of channel activation. The data were modeled by a gating particle undergoing Brownian motion in a one-dimensional diffusion landscape that featured diminishing electrical resistance and entropy in the direction of channel activation. The final open state of the channel was reasoned to be narrow and deep to account for successful subtraction of linear-charge displacements at positive potentials. The overall picture of gating that emerges from these studies is that the channel experiences incremental organization from a relaxed state in the early steps of activation to a rigidly structured open state.
Allen,
Brownian dynamics study of an open-state KcsA potassium channel.
2001, Pubmed
Allen,
Brownian dynamics study of an open-state KcsA potassium channel.
2001,
Pubmed
Bernèche,
Energetics of ion conduction through the K+ channel.
2001,
Pubmed
Bezanilla,
The voltage sensor in voltage-dependent ion channels.
2000,
Pubmed
Bezanilla,
Molecular basis of gating charge immobilization in Shaker potassium channels.
1991,
Pubmed
,
Xenbase
Correa,
Gating kinetics of batrachotoxin-modified Na+ channels in the squid giant axon. Voltage and temperature effects.
1992,
Pubmed
Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed
Fenimore,
Slaving: solvent fluctuations dominate protein dynamics and functions.
2002,
Pubmed
Forster,
The early phase of sodium channel gating current in the squid giant axon. Characteristics of a fast component of displacement charge movement.
1992,
Pubmed
Frauenfelder,
The energy landscapes and motions of proteins.
1991,
Pubmed
Jiang,
X-ray structure of a voltage-dependent K+ channel.
2003,
Pubmed
Perozo,
Gating currents from a nonconducting mutant reveal open-closed conformations in Shaker K+ channels.
1993,
Pubmed
Rodríguez,
Voltage gating of Shaker K+ channels. The effect of temperature on ionic and gating currents.
1998,
Pubmed
,
Xenbase
Schoppa,
The size of gating charge in wild-type and mutant Shaker potassium channels.
1992,
Pubmed
Sigg,
Kramers' diffusion theory applied to gating kinetics of voltage-dependent ion channels.
1999,
Pubmed
Sigg,
A physical model of potassium channel activation: from energy landscape to gating kinetics.
2003,
Pubmed
,
Xenbase
Stefani,
Gating of Shaker K+ channels: I. Ionic and gating currents.
1994,
Pubmed
,
Xenbase
Zhou,
Chemistry of ion coordination and hydration revealed by a K+ channel-Fab complex at 2.0 A resolution.
2001,
Pubmed
Zwanzig,
Diffusion in a rough potential.
1988,
Pubmed
