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Plant Cell
2005 May 01;175:1532-48. doi: 10.1105/tpc.104.030551.
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Regulation by external K+ in a maize inward shaker channel targets transport activity in the high concentration range.
Su YH
,
North H
,
Grignon C
,
Thibaud JB
,
Sentenac H
,
Véry AA
.
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An inward Shaker K(+) channel identified in Zea mays (maize), ZmK2.1, displays strong regulation by external K(+) when expressed in Xenopus laevis (African clawed frog) oocytes or COS cells. ZmK2.1 is specifically activated by K(+) with an apparent K(m) close to 15 mM independent of the membrane hyperpolarization level. In the absence of K(+), ZmK2.1 appears to enter a nonconducting state. Thus, whatever the membrane potential, this maize channel cannot mediate K(+) influx in the submillimolar concentration range, unlike its relatives in Arabidopsis thaliana. Its expression is restricted to the shoots, the strongest signal (RT-PCR) being associated with vascular/bundle sheath strands. Based on sequence and gene structure, the closest relatives of ZmK2.1 in Arabidopsis are K(+) Arabidopsis Transporter 1 (KAT1) (expressed in guard cells) and KAT2 (expressed in guard cells and leaf phloem). Patch-clamp analyses of guard cell protoplasts reveal a higher functional diversity of K(+) channels in maize than in Arabidopsis. Channels endowed with regulation by external K(+) similar to that of ZmK2.1 (channel activity regulated by external K(+) with a K(m) close to 15 mM, regulation independent of external Ca(2+)) constitute a major component of the maize guard cell inward K(+) channel population. The presence of such channels in maize might reflect physiological traits of C4 and/or monocotyledonous plants.
Aiyar,
The P-region and S6 of Kv3.1 contribute to the formation of the ion conduction pathway.
1994, Pubmed,
Xenbase
Aiyar,
The P-region and S6 of Kv3.1 contribute to the formation of the ion conduction pathway.
1994,
Pubmed
,
Xenbase
Anderson,
Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.
1992,
Pubmed
Assmann,
From milliseconds to millions of years: guard cells and environmental responses.
2001,
Pubmed
Blatt,
K+ channels of stomatal guard cells. Characteristics of the inward rectifier and its control by pH.
1992,
Pubmed
Blatt,
Potassium channel currents in intact stomatal guard cells: rapid enhancement by abscisic acid.
1990,
Pubmed
Blaustein,
Tethered blockers as molecular 'tape measures' for a voltage-gated K+ channel.
2000,
Pubmed
,
Xenbase
Bonneaud,
A family of low and high copy replicative, integrative and single-stranded S. cerevisiae/E. coli shuttle vectors.
1991,
Pubmed
Brüggemann,
Channel-mediated high-affinity K+ uptake into guard cells from Arabidopsis.
1999,
Pubmed
Church,
Genomic sequencing.
1984,
Pubmed
Consiglio,
Influence of pore residues on permeation properties in the Kv2.1 potassium channel. Evidence for a selective functional interaction of K+ with the outer vestibule.
2003,
Pubmed
Decher,
KCNE2 modulates current amplitudes and activation kinetics of HCN4: influence of KCNE family members on HCN4 currents.
2003,
Pubmed
,
Xenbase
Dennison,
Functions of AKT1 and AKT2 potassium channels determined by studies of single and double mutants of Arabidopsis.
2001,
Pubmed
Doyle,
The structure of the potassium channel: molecular basis of K+ conduction and selectivity.
1998,
Pubmed
Epstein,
RESOLUTION OF DUAL MECHANISMS OF POTASSIUM ABSORPTION BY BARLEY ROOTS.
1963,
Pubmed
Fairley-Grenot,
Comparison of K(+)-channel activation and deactivation in guard cells from a dicotyledon (Vicia faba L.) and a graminaceous monocotyledon (Zea mays).
1993,
Pubmed
Fairley-Grenot,
Whole-cell K(+) current across the plasma membrane of guard cells from a grass: Zea mays.
1992,
Pubmed
Fairley-Grenot,
Permeation of Ca2+ through K+ channels in the plasma membrane of Vicia faba guard cells.
1992,
Pubmed
Gaymard,
Identification and disruption of a plant shaker-like outward channel involved in K+ release into the xylem sap.
1998,
Pubmed
,
Xenbase
Geiger,
Outer pore residues control the H(+) and K(+) sensitivity of the Arabidopsis potassium channel AKT3.
2002,
Pubmed
,
Xenbase
Harris,
A permanent ion binding site located between two gates of the Shaker K+ channel.
1998,
Pubmed
,
Xenbase
Hirsch,
A role for the AKT1 potassium channel in plant nutrition.
1998,
Pubmed
Hosy,
The Arabidopsis outward K+ channel GORK is involved in regulation of stomatal movements and plant transpiration.
2003,
Pubmed
Immke,
Potassium-dependent changes in the conformation of the Kv2.1 potassium channel pore.
1999,
Pubmed
Jäger,
Regulation of a mammalian Shaker-related potassium channel, hKv1.5, by extracellular potassium and pH.
2001,
Pubmed
Jäger,
Regulation of mammalian Shaker-related K+ channels: evidence for non-conducting closed and non-conducting inactivated states.
1998,
Pubmed
Jan,
Cloned potassium channels from eukaryotes and prokaryotes.
1997,
Pubmed
Jiang,
X-ray structure of a voltage-dependent K+ channel.
2003,
Pubmed
Jiang,
The principle of gating charge movement in a voltage-dependent K+ channel.
2003,
Pubmed
Kiss,
Contribution of the selectivity filter to inactivation in potassium channels.
1999,
Pubmed
Kiss,
Modulation of C-type inactivation by K+ at the potassium channel selectivity filter.
1998,
Pubmed
Kuo,
Crystal structure of the potassium channel KirBac1.1 in the closed state.
2003,
Pubmed
Kwak,
Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis.
2001,
Pubmed
Lacombe,
A shaker-like K(+) channel with weak rectification is expressed in both source and sink phloem tissues of Arabidopsis.
2000,
Pubmed
,
Xenbase
Liman,
Voltage-sensing residues in the S4 region of a mammalian K+ channel.
1991,
Pubmed
,
Xenbase
Liu,
A side chain in S6 influences both open-state stability and ion permeation in a voltage-gated K+ channel.
1998,
Pubmed
,
Xenbase
Lopez,
Evidence that the S6 segment of the Shaker voltage-gated K+ channel comprises part of the pore.
1994,
Pubmed
,
Xenbase
Mäser,
Phylogenetic relationships within cation transporter families of Arabidopsis.
2001,
Pubmed
Morais-Cabral,
Energetic optimization of ion conduction rate by the K+ selectivity filter.
2001,
Pubmed
Mouline,
Pollen tube development and competitive ability are impaired by disruption of a Shaker K(+) channel in Arabidopsis.
2002,
Pubmed
Müller-Röber,
Cloning and electrophysiological analysis of KST1, an inward rectifying K+ channel expressed in potato guard cells.
1995,
Pubmed
,
Xenbase
Nakamura,
Expression of an Arabidopsis potassium channel gene in guard cells.
1995,
Pubmed
Pardo,
Extracellular K+ specifically modulates a rat brain K+ channel.
1992,
Pubmed
,
Xenbase
Philippar,
The K+ channel KZM1 mediates potassium uptake into the phloem and guard cells of the C4 grass Zea mays.
2003,
Pubmed
,
Xenbase
Philippar,
Auxin-induced K+ channel expression represents an essential step in coleoptile growth and gravitropism.
1999,
Pubmed
,
Xenbase
Pilot,
Five-group distribution of the Shaker-like K+ channel family in higher plants.
2003,
Pubmed
Pilot,
Guard cell inward K+ channel activity in arabidopsis involves expression of the twin channel subunits KAT1 and KAT2.
2001,
Pubmed
,
Xenbase
Plesch,
Involvement of TAAAG elements suggests a role for Dof transcription factors in guard cell-specific gene expression.
2001,
Pubmed
Pratelli,
A grapevine gene encoding a guard cell K(+) channel displays developmental regulation in the grapevine berry.
2002,
Pubmed
,
Xenbase
Ruta,
Functional analysis of an archaebacterial voltage-dependent K+ channel.
2003,
Pubmed
Savino,
Inhibition of the iron-induced ZmFer1 maize ferritin gene expression by antioxidants and serine/threonine phosphatase inhibitors.
1997,
Pubmed
Sentenac,
Cloning and expression in yeast of a plant potassium ion transport system.
1992,
Pubmed
Szyroki,
KAT1 is not essential for stomatal opening.
2001,
Pubmed
Thompson,
Affinity and location of an internal K+ ion binding site in shaker K channels.
2001,
Pubmed
,
Xenbase
Vergara,
Localization of the K+ lock-In and the Ba2+ binding sites in a voltage-gated calcium-modulated channel. Implications for survival of K+ permeability.
1999,
Pubmed
Véry,
Level of expression in Xenopus oocytes affects some characteristics of a plant inward-rectifying voltage-gated K+ channel.
1994,
Pubmed
,
Xenbase
Véry,
Cation channels in the Arabidopsis plasma membrane.
2002,
Pubmed
Véry,
Molecular mechanisms and regulation of K+ transport in higher plants.
2003,
Pubmed
Véry,
Expression of a cloned plant K+ channel in Xenopus oocytes: analysis of macroscopic currents.
1995,
Pubmed
,
Xenbase
Zagotta,
Shaker potassium channel gating. II: Transitions in the activation pathway.
1994,
Pubmed
,
Xenbase
Zei,
Effects on ion permeation with hydrophobic substitutions at a residue in Shaker S6 that interacts with a signature sequence amino acid.
1999,
Pubmed
,
Xenbase
Zimmermann,
Ion channels in plant signaling.
1999,
Pubmed
