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Proc Natl Acad Sci U S A
1999 Aug 17;9617:9926-31. doi: 10.1073/pnas.96.17.9926.
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Cytoplasmic amino and carboxyl domains form a wide intracellular vestibule in an inwardly rectifying potassium channel.
Lu T, Zhu YG, Yang J.
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We have studied the structural components and architecture of the intracellular vestibule of a strongly rectifying channel (Kir2.1) expressed in Xenopus oocytes. Putative vestibule-lining residues were identified by systematically examining covalent modification by sulfhydryl-specific reagents of cysteine residues engineered into two cytoplasmic regions. In a stretch of 33 amino acids in the amino terminus (from C54 to V86) and 22 amino acids in the carboxyl terminus (from R213 to S234), 15 and 11 residues, respectively, were found to be accessible to methanethiosulfonate ethylammonium (MTSEA) or methanethiosulfonate ethyltrimethylammonium (MTSET) and presumably project into the aqueous intracellular vestibule. The pattern of accessibility suggests that both stretches may adopt an extended loop structure. To explore the physical dimension of the intracellular vestibule, we covalently linked a constrained number (one to four) of positively charged moieties of different sizes to the E224 position and found that this vestibule region is sufficiently wide to accommodate four modifying groups with dimensions of 12 A x 10 A x 6 A. These results suggest that regions in both the amino and carboxyl domains of Kir2.1 channel form a long and wide intracellular vestibule that protrudes beyond the membrane into the cytoplasm.
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,
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,
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1995,
Pubmed
,
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1996,
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,
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1994,
Pubmed
,
Xenbase Hagiwara,
Potassium current and the effect of cesium on this current during anomalous rectification of the egg cell membrane of a starfish.
1976,
Pubmed Ho,
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1993,
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,
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1991,
Pubmed
,
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The Mg2+ block and intrinsic gating underlying inward rectification of the K+ current in guinea-pig cardiac myocytes.
1989,
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Substituted-cysteine accessibility method.
1998,
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Bimane fluorescent labels: labeling of normal human red cells under physiological conditions.
1979,
Pubmed Kubo,
Primary structure and functional expression of a mouse inward rectifier potassium channel.
1993,
Pubmed
,
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1992,
Pubmed
,
Xenbase Lopatin,
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1994,
Pubmed
,
Xenbase Lu,
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1994,
Pubmed
,
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1999,
Pubmed
,
Xenbase Matsuda,
Open-state substructure of inwardly rectifying potassium channels revealed by magnesium block in guinea-pig heart cells.
1988,
Pubmed Matsuda,
Ohmic conductance through the inwardly rectifying K channel and blocking by internal Mg2+.
,
Pubmed Nichols,
Mg(2+)-dependent inward rectification of ROMK1 potassium channels expressed in Xenopus oocytes.
1994,
Pubmed
,
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pH-dependent gating of ROMK (Kir1.1) channels involves conformational changes in both N and C termini.
1998,
Pubmed
,
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The S4-S5 loop contributes to the ion-selective pore of potassium channels.
1993,
Pubmed
,
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A single aspartate residue is involved in both intrinsic gating and blockage by Mg2+ of the inward rectifier, IRK1.
1994,
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Electrostatic potential of the acetylcholine binding sites in the nicotinic receptor probed by reactions of binding-site cysteines with charged methanethiosulfonates.
1994,
Pubmed Taglialatela,
C-terminus determinants for Mg2+ and polyamine block of the inward rectifier K+ channel IRK1.
1995,
Pubmed
,
Xenbase Taglialatela,
Specification of pore properties by the carboxyl terminus of inwardly rectifying K+ channels.
1994,
Pubmed
,
Xenbase Trapp,
Mechanism of ATP-sensitive K channel inhibition by sulfhydryl modification.
1998,
Pubmed
,
Xenbase Vandenberg,
Inward rectification of a potassium channel in cardiac ventricular cells depends on internal magnesium ions.
1987,
Pubmed Yang,
Control of rectification and permeation by residues in two distinct domains in an inward rectifier K+ channel.
1995,
Pubmed
,
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1997,
Pubmed
,
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,
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