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.
Plant Cell
2005 May 01;175:1532-48. doi: 10.1105/tpc.104.030551.
Show Gene links
Show Anatomy links
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
.
???displayArticle.abstract???
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,
Potassium channel currents in intact stomatal guard cells: rapid enhancement by abscisic acid.
1990,
Pubmed
Blatt,
K+ channels of stomatal guard cells. Characteristics of the inward rectifier and its control by pH.
1992,
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,
Whole-cell K(+) current across the plasma membrane of guard cells from a grass: Zea mays.
1992,
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,
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
Jan,
Cloned potassium channels from eukaryotes and prokaryotes.
1997,
Pubmed
Jiang,
The principle of gating charge movement in a voltage-dependent K+ channel.
2003,
Pubmed
Jiang,
X-ray structure of a voltage-dependent K+ channel.
2003,
Pubmed
Jäger,
Regulation of mammalian Shaker-related K+ channels: evidence for non-conducting closed and non-conducting inactivated states.
1998,
Pubmed
Jäger,
Regulation of a mammalian Shaker-related potassium channel, hKv1.5, by extracellular potassium and pH.
2001,
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
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
Mäser,
Phylogenetic relationships within cation transporter families of Arabidopsis.
2001,
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,
Molecular mechanisms and regulation of K+ transport in higher plants.
2003,
Pubmed
Véry,
Cation channels in the Arabidopsis plasma membrane.
2002,
Pubmed
Véry,
Level of expression in Xenopus oocytes affects some characteristics of a plant inward-rectifying voltage-gated K+ channel.
1994,
Pubmed
,
Xenbase
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