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.
Biophys J
2004 Aug 01;872:858-72. doi: 10.1529/biophysj.103.037671.
Show Gene links
Show Anatomy links
Assembly of plant Shaker-like K(out) channels requires two distinct sites of the channel alpha-subunit.
Dreyer I
,
Porée F
,
Schneider A
,
Mittelstädt J
,
Bertl A
,
Sentenac H
,
Thibaud JB
,
Mueller-Roeber B
.
???displayArticle.abstract???
SKOR and GORK are outward-rectifying plant potassium channels from Arabidopsis thaliana. They belong to the Shaker superfamily of voltage-dependent K(+) channels. Channels of this class are composed of four alpha-subunits and subunit assembly is a prerequisite for channel function. In this study the assembly mechanism of SKOR was investigated using the yeast two-hybrid system and functional assays in Xenopus oocytes and in yeast. We demonstrate that SKOR and GORK physically interact and assemble into heteromeric K(out) channels. Deletion mutants and chimeric proteins generated from SKOR and the K(in) channel alpha-subunit KAT1 revealed that the cytoplasmic C-terminus of SKOR determines channel assembly. Two domains that are crucial for channel assembly were identified: i), a proximal interacting region comprising a putative cyclic nucleotide-binding domain together with 33 amino acids just upstream of this domain, and ii), a distal interacting region showing some resemblance to the K(T) domain of KAT1. Both regions contributed differently to channel assembly. Whereas the proximal interacting region was found to be active on its own, the distal interacting region required an intact proximal interacting region to be active. K(out) alpha-subunits did not assemble with K(in) alpha-subunits because of the absence of interaction between their assembly sites.
Ache,
GORK, a delayed outward rectifier expressed in guard cells of Arabidopsis thaliana, is a K(+)-selective, K(+)-sensing ion channel.
2000, Pubmed,
Xenbase
Ache,
GORK, a delayed outward rectifier expressed in guard cells of Arabidopsis thaliana, is a K(+)-selective, K(+)-sensing ion channel.
2000,
Pubmed
,
Xenbase
Ache,
VFK1, a Vicia faba K(+) channel involved in phloem unloading.
2001,
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
Becker,
Changes in voltage activation, Cs+ sensitivity, and ion permeability in H5 mutants of the plant K+ channel KAT1.
1996,
Pubmed
,
Xenbase
Bertl,
Electrophysiology in the eukaryotic model cell Saccharomyces cerevisiae.
1998,
Pubmed
Daram,
Tetramerization of the AKT1 plant potassium channel involves its C-terminal cytoplasmic domain.
1997,
Pubmed
den Dunnen,
Nomenclature for the description of human sequence variations.
2001,
Pubmed
Dreyer,
Plant K+ channel alpha-subunits assemble indiscriminately.
1997,
Pubmed
,
Xenbase
Ehrhardt,
Association of plant K+(in) channels is mediated by conserved C-termini and does not affect subunit assembly.
1997,
Pubmed
Gaymard,
Identification and disruption of a plant shaker-like outward channel involved in K+ release into the xylem sap.
1998,
Pubmed
,
Xenbase
Gietz,
Improved method for high efficiency transformation of intact yeast cells.
1992,
Pubmed
Hosy,
The Arabidopsis outward K+ channel GORK is involved in regulation of stomatal movements and plant transpiration.
2003,
Pubmed
Jenke,
C-terminal domains implicated in the functional surface expression of potassium channels.
2003,
Pubmed
,
Xenbase
Lacombe,
Evidence for a multi-ion pore behavior in the plant potassium channel KAT1.
1998,
Pubmed
,
Xenbase
Langer,
Poplar potassium transporters capable of controlling K+ homeostasis and K+-dependent xylogenesis.
2002,
Pubmed
,
Xenbase
Li,
Specification of subunit assembly by the hydrophilic amino-terminal domain of the Shaker potassium channel.
1992,
Pubmed
Ludwig,
Carboxy-terminal domain mediates assembly of the voltage-gated rat ether-à-go-go potassium channel.
1997,
Pubmed
Lupas,
Predicting coiled coils from protein sequences.
1991,
Pubmed
Ma,
ER transport signals and trafficking of potassium channels and receptors.
2002,
Pubmed
Marten,
Voltage-dependent gating characteristics of the K+ channel KAT1 depend on the N and C termini.
1997,
Pubmed
Mäser,
Phylogenetic relationships within cation transporter families of Arabidopsis.
2001,
Pubmed
Minet,
Complementation of Saccharomyces cerevisiae auxotrophic mutants by Arabidopsis thaliana cDNAs.
1992,
Pubmed
Moshelion,
Diurnal and circadian regulation of putative potassium channels in a leaf moving organ.
2002,
Pubmed
Pilot,
Regulated expression of Arabidopsis shaker K+ channel genes involved in K+ uptake and distribution in the plant.
2003,
Pubmed
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
Rodríguez-Navarro,
Dual system for potassium transport in Saccharomyces cerevisiae.
1984,
Pubmed
Schmitt,
A recessive C-terminal Jervell and Lange-Nielsen mutation of the KCNQ1 channel impairs subunit assembly.
2000,
Pubmed
,
Xenbase
Sentenac,
Cloning and expression in yeast of a plant potassium ion transport system.
1992,
Pubmed
Tu,
Evidence for dimerization of dimers in K+ channel assembly.
1999,
Pubmed
,
Xenbase
van der Ven,
Indications for a novel muscular dystrophy pathway. gamma-filamin, the muscle-specific filamin isoform, interacts with myotilin.
2000,
Pubmed
Véry,
Molecular mechanisms and regulation of K+ transport in higher plants.
2003,
Pubmed
Véry,
Cation channels in the Arabidopsis plasma membrane.
2002,
Pubmed
Wainger,
Molecular mechanism of cAMP modulation of HCN pacemaker channels.
2001,
Pubmed
Zagotta,
Structural basis for modulation and agonist specificity of HCN pacemaker channels.
2003,
Pubmed
Zimmermann,
The K+ channel SKT1 is co-expressed with KST1 in potato guard cells--both channels can co-assemble via their conserved KT domains.
2001,
Pubmed
,
Xenbase
