Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
The Arabidopsis thaliana KAT1, an inward-rectifying potassium channel, shares molecular features with the Shaker family of outward rectifier K(+) channels. The KAT1 amino-acid sequence reveals the presence of a positively charged S4 and a segment containing the TXGYGD signature sequence in the pore (P) region. To test whether the inward-rectifying properties of KAT1 are due to reverse orientation in the membrane, such that the voltage sensor is oriented in the opposite direction of the electric field compared with the Shaker K(+) channel, we have inserted a flag epitope in the NH(2) terminus or the S3-S4 loop. The KAT1 and tagged constructs expressed functional channels in whole cells, Xenopus oocytes and COS-7. The electrophysiological properties of both tagged constructs were similar to those of the wild type. Immunofluorescence with an antibody against the flag epitope and an anti-C terminal KAT1 determined the membrane localization of these epitopes and the orientation of the KAT1 channel in the membrane. Our data confirm that KAT1 in eukaryotic cells has an orientation similar to the Shaker K(+) channel.
Anderson,
Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.
1992, Pubmed
Anderson,
Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.
1992,
Pubmed
Cao,
Amino terminus and the first four membrane-spanning segments of the Arabidopsis K+ channel KAT1 confer inward-rectification property of plant-animal chimeric channels.
1995,
Pubmed
,
Xenbase
Clapham,
Not so funny anymore: pacing channels are cloned.
1998,
Pubmed
Claros,
TopPred II: an improved software for membrane protein structure predictions.
1994,
Pubmed
Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed
Dreyer,
A plant Shaker-like K+ channel switches between two distinct gating modes resulting in either inward-rectifying or "leak" current.
2001,
Pubmed
,
Xenbase
Gauss,
Molecular identification of a hyperpolarization-activated channel in sea urchin sperm.
1998,
Pubmed
Gaymard,
The baculovirus/insect cell system as an alternative to Xenopus oocytes. First characterization of the AKT1 K+ channel from Arabidopsis thaliana.
1996,
Pubmed
,
Xenbase
Gonzalez,
Modulation of the Shaker K(+) channel gating kinetics by the S3-S4 linker.
2000,
Pubmed
,
Xenbase
Ichida,
Increased resistance to extracellular cation block by mutation of the pore domain of the Arabidopsis inward-rectifying K+ channel KAT1.
1996,
Pubmed
Johnston,
Aggresomes: a cellular response to misfolded proteins.
1998,
Pubmed
Latorre,
Molecular coupling between voltage sensor and pore opening in the Arabidopsis inward rectifier K+ channel KAT1.
2003,
Pubmed
Latorre,
Structure and function of potassium channels in plants: some inferences about the molecular origin of inward rectification in KAT1 channels (Review).
2003,
Pubmed
Marten,
The N-terminus of the K channel KAT1 controls its voltage-dependent gating by altering the membrane electric field.
1998,
Pubmed
,
Xenbase
Meera,
Large conductance voltage- and calcium-dependent K+ channel, a distinct member of voltage-dependent ion channels with seven N-terminal transmembrane segments (S0-S6), an extracellular N terminus, and an intracellular (S9-S10) C terminus.
1997,
Pubmed
Männikkö,
Voltage-sensing mechanism is conserved among ion channels gated by opposite voltages.
2002,
Pubmed
,
Xenbase
Nakamura,
Expression of an Arabidopsis potassium channel gene in guard cells.
1995,
Pubmed
Roelfsema,
Ion channels in guard cells of Arabidopsis thaliana (L.) Heynh.
1997,
Pubmed
Sato,
Molecular dissection of the contribution of negatively and positively charged residues in S2, S3, and S4 to the final membrane topology of the voltage sensor in the K+ channel, KAT1.
2003,
Pubmed
,
Xenbase
Sato,
Integration of Shaker-type K+ channel, KAT1, into the endoplasmic reticulum membrane: synergistic insertion of voltage-sensing segments, S3-S4, and independent insertion of pore-forming segments, S5-P-S6.
2002,
Pubmed
,
Xenbase
Schroeder,
Perspectives on the physiology and structure of inward-rectifying K+ channels in higher plants: biophysical implications for K+ uptake.
1994,
Pubmed
Sentenac,
Cloning and expression in yeast of a plant potassium ion transport system.
1992,
Pubmed
Sesti,
Hyperpolarization moves S4 sensors inward to open MVP, a methanococcal voltage-gated potassium channel.
2003,
Pubmed
Shih,
Topology of the Shaker potassium channel probed with hydrophilic epitope insertions.
1997,
Pubmed
,
Xenbase
Szabò,
Temperature-dependent functional expression of a plant K(+) channel in mammalian cells.
2000,
Pubmed
Szyroki,
KAT1 is not essential for stomatal opening.
2001,
Pubmed
Taglialatela,
Gating currents of the cloned delayed-rectifier K+ channel DRK1.
1993,
Pubmed
,
Xenbase
Uozumi,
Determination of transmembrane topology of an inward-rectifying potassium channel from Arabidopsis thaliana based on functional expression in Escherichia coli.
1998,
Pubmed
Véry,
Molecular mechanisms and regulation of K+ transport in higher plants.
2003,
Pubmed
Wang,
Site-directed anti-peptide antibodies define the topography of the beta-adrenergic receptor.
1989,
Pubmed
Zei,
Voltage-dependent gating of single wild-type and S4 mutant KAT1 inward rectifier potassium channels.
1998,
Pubmed
,
Xenbase
von Heijne,
Membrane protein structure prediction. Hydrophobicity analysis and the positive-inside rule.
1992,
Pubmed
