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EMBO Rep
2003 Jan 01;41:70-5. doi: 10.1038/sj.embor.embor708.
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The ligand-sensitive gate of a potassium channel lies close to the selectivity filter.
Proks P, Antcliff JF, Ashcroft FM.
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Potassium channels selectively conduct K(+) ions across cell membranes and have key roles in cell excitability. Their opening and closing can be spontaneous or controlled by membrane voltage or ligand binding. We used Ba(2+) as a probe to determine the location of the ligand-sensitive gate in an inwardly rectifying K(+) channel (Kir6.2). To a K(+) channel, Ba(2+) and K(+) are of similar sizes, but Ba(2+) blocks the pore by binding within the selectivity filter. We found that internal Ba(2+) could still access its binding site when the channel was shut, which indicates that the ligand-sensitive gate lies above the Ba(2+)-block site, and thus within or above the selectivity filter. This is in marked contrast to the voltage-dependent gate of K(V) channels, which is located at the intracellular mouth of the pore.
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Mechanism of Ba(2+) block of a mouse inwardly rectifying K+ channel: differential contribution by two discrete residues.
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Pubmed
,
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Block of squid axon K channels by internally and externally applied barium ions.
1982,
Pubmed Ashcroft,
ATP-sensitive K+ channels and insulin secretion: their role in health and disease.
1999,
Pubmed Capener,
Homology modeling and molecular dynamics simulation studies of an inward rectifier potassium channel.
2000,
Pubmed del Camino,
Blocker protection in the pore of a voltage-gated K+ channel and its structural implications.
2000,
Pubmed del Camino,
Tight steric closure at the intracellular activation gate of a voltage-gated K(+) channel.
2001,
Pubmed Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed Fan,
Phosphoinositides decrease ATP sensitivity of the cardiac ATP-sensitive K(+) channel. A molecular probe for the mechanism of ATP-sensitive inhibition.
1999,
Pubmed Flynn,
Conformational changes in S6 coupled to the opening of cyclic nucleotide-gated channels.
2001,
Pubmed
,
Xenbase Gillis,
Effects of sulfonamides on a metabolite-regulated ATPi-sensitive K+ channel in rat pancreatic B-cells.
1989,
Pubmed Gribble,
MgATP activates the beta cell KATP channel by interaction with its SUR1 subunit.
1998,
Pubmed
,
Xenbase Jiang,
The open pore conformation of potassium channels.
2002,
Pubmed Jiang,
The barium site in a potassium channel by x-ray crystallography.
2000,
Pubmed Liu,
Structure of the KcsA channel intracellular gate in the open state.
2001,
Pubmed Lu,
Probing ion permeation and gating in a K+ channel with backbone mutations in the selectivity filter.
2001,
Pubmed
,
Xenbase Neyton,
Discrete Ba2+ block as a probe of ion occupancy and pore structure in the high-conductance Ca2+ -activated K+ channel.
1988,
Pubmed Neyton,
Potassium blocks barium permeation through a calcium-activated potassium channel.
1988,
Pubmed Perozo,
Structural rearrangements underlying K+-channel activation gating.
1999,
Pubmed Proks,
Mutations within the P-loop of Kir6.2 modulate the intraburst kinetics of the ATP-sensitive potassium channel.
2001,
Pubmed
,
Xenbase Trapp,
Molecular analysis of ATP-sensitive K channel gating and implications for channel inhibition by ATP.
1998,
Pubmed
,
Xenbase Zhou,
Chemistry of ion coordination and hydration revealed by a K+ channel-Fab complex at 2.0 A resolution.
2001,
Pubmed Zhou,
Mutations in the pore region of ROMK enhance Ba2+ block.
1996,
Pubmed
,
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