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.
J Bioenerg Biomembr
2001 Feb 01;331:63-71. doi: 10.1023/a:1005676724618.
Show Gene links
Show Anatomy links
A novel K+ channel expressed in carrot roots with a low susceptibility toward metal ions.
Paganetto A
,
Bregante M
,
Downey P
,
Lo Schiavo F
,
Hoth S
,
Hedrich R
,
Gambale F
.
???displayArticle.abstract???
Kdc1 is a novel K+-channel gene cloned from carrot roots, and which is also present in cultured carrot cells. We investigated the characteristics of the ionic current elicited in Xenopus oocytes coinjected with KDC1 (K+-Daucus carota 1) and KAT1 (from Arabidopsis thaliana) RNA. Expressed heteromeric channels displayed inward-rectifying potassium currents whose kinetics, voltage characteristics, and inhibition by metal ions depended on KDC1:KAT1 ratios. At low KDC1:KAT1 ratios, Zn2+ inhibition of heteromeric K+ current was less pronounced compared to homomeric KAT1 channels, while at higher KDC1:KAT1 ratios, the addition of Zn2+ even produced an increase in current. Under the same conditions, the Ni2+ inhibition of the current was also reduced, but no current increase was observed. These effects might be explained by the unusual amino acid composition of the KDC1 protein in terms of histidine residues that are absent in the pore region, but abundant (four per subunit) in the proximity of the pore entrance. Channels like KDC1 could be at least partially responsible for the higher resistance of carrot cells in the presence of metals.
Ackerman,
Hypotonicity activates a native chloride current in Xenopus oocytes.
1994, Pubmed,
Xenbase
Ackerman,
Hypotonicity activates a native chloride current in Xenopus oocytes.
1994,
Pubmed
,
Xenbase
Baizabal-Aguirre,
Suppression of inward-rectifying K+ channels KAT1 and AKT2 by dominant negative point mutations in the KAT1 alpha-subunit.
1999,
Pubmed
Bregante,
Ionic transport in the plasma membrane of carrot protoplasts from embryogenic cell-suspension cultures.
1996,
Pubmed
Chakrabarti,
Geometry of interaction of metal ions with histidine residues in protein structures.
1990,
Pubmed
Chao,
Regulation of endogenous chloride conductance in Xenopus oocytes.
1991,
Pubmed
,
Xenbase
Downey,
KDC1, a novel carrot root hair K+ channel. Cloning, characterization, and expression in mammalian cells.
2000,
Pubmed
Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed
Dreyer,
Plant K+ channel alpha-subunits assemble indiscriminately.
1997,
Pubmed
,
Xenbase
Elinder,
Role of individual surface charges of voltage-gated K channels.
1999,
Pubmed
Elinder,
Surface Charges of K channels. Effects of strontium on five cloned channels expressed in Xenopus oocytes.
1996,
Pubmed
,
Xenbase
Gaymard,
Identification and disruption of a plant shaker-like outward channel involved in K+ release into the xylem sap.
1998,
Pubmed
,
Xenbase
Hedrich,
Inward rectifier potassium channels in plants differ from their animal counterparts in response to voltage and channel modulators.
1995,
Pubmed
,
Xenbase
Heginbotham,
The aromatic binding site for tetraethylammonium ion on potassium channels.
1992,
Pubmed
Hoth,
Susceptibility of the guard-cell K(+)-uptake channel KST1 to Zn(2+) requires histidine residues in the S3-S4 linker and in the channel pore.
1999,
Pubmed
,
Xenbase
Hoth,
Distinct molecular bases for pH sensitivity of the guard cell K+ channels KST1 and KAT1.
1999,
Pubmed
,
Xenbase
Hoth,
Molecular basis of plant-specific acid activation of K+ uptake channels.
1997,
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
Lacombe,
A shaker-like K(+) channel with weak rectification is expressed in both source and sink phloem tissues of Arabidopsis.
2000,
Pubmed
,
Xenbase
Lee,
Structural determinant for assembly of mammalian K+ channels.
1994,
Pubmed
,
Xenbase
Liman,
Subunit stoichiometry of a mammalian K+ channel determined by construction of multimeric cDNAs.
1992,
Pubmed
,
Xenbase
Lynch,
A mutation in the transmembrane/luminal domain of the ryanodine receptor is associated with abnormal Ca2+ release channel function and severe central core disease.
1999,
Pubmed
Maathuis,
Plasma membrane transport in context - making sense out of complexity.
1999,
Pubmed
Machaca,
Asymmetrical distribution of Ca-activated Cl channels in Xenopus oocytes.
1998,
Pubmed
,
Xenbase
Marten,
AKT3, a phloem-localized K+ channel, is blocked by protons.
1999,
Pubmed
,
Xenbase
Philippar,
Auxin-induced K+ channel expression represents an essential step in coleoptile growth and gravitropism.
1999,
Pubmed
,
Xenbase
Schoppa,
The size of gating charge in wild-type and mutant Shaker potassium channels.
1992,
Pubmed
Uozumi,
Determination of transmembrane topology of an inward-rectifying potassium channel from Arabidopsis thaliana based on functional expression in Escherichia coli.
1998,
Pubmed
Véry,
Level of expression in Xenopus oocytes affects some characteristics of a plant inward-rectifying voltage-gated K+ channel.
1994,
Pubmed
,
Xenbase
Yellen,
Mutations affecting internal TEA blockade identify the probable pore-forming region of a K+ channel.
1991,
Pubmed
