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.
Rundown of the hyperpolarization-activated KAT1 channel involves slowing of the opening transitions regulated by phosphorylation.
Tang XD
,
Hoshi T
.
???displayArticle.abstract???
Disappearance of the functional activity or rundown of ion channels upon patch excision in many cells involves a decrease in the number of channels available to open. A variety of cellular and biophysical mechanisms have been shown to be involved in the rundown of different ion channels. We examined the rundown process of the plant hyperpolarization-activated KAT1 K+ channel expressed in Xenopus oocytes. The decrease in the KAT1 channel activity on patch excision was accompanied by progressive slowing of the activation time course, and it was caused by a shift in the voltage dependence of the channel without any change in the single-channel amplitude. The single-channel analysis showed that patch excision alters only the transitions leading up to the burst states of the channel. Patch cramming or concurrent application of protein kinase A (PKA) and ATP restored the channel activity. In contrast, nonspecific alkaline phosphatase (ALP) accelerated the rundown time course. Low internal pH, which inhibits ALP activity, slowed the KAT1 rundown time course. The results show that the opening transitions of the KAT1 channel are enhanced not only by hyperpolarization but also by PKA-mediated phosphorylation.
Anderson,
Nucleoside triphosphates are required to open the CFTR chloride channel.
1991, Pubmed
Anderson,
Nucleoside triphosphates are required to open the CFTR chloride channel.
1991,
Pubmed
Anderson,
Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.
1992,
Pubmed
Armstrong,
Voltage-activated calcium channels that must be phosphorylated to respond to membrane depolarization.
1987,
Pubmed
Armstrong,
Sensitivity to abscisic acid of guard-cell K+ channels is suppressed by abi1-1, a mutant Arabidopsis gene encoding a putative protein phosphatase.
1995,
Pubmed
Becq,
Ionic channel rundown in excised membrane patches.
1996,
Pubmed
Bei,
Functional expression and characterization of a plant K+ channel gene in a plant cell model.
1998,
Pubmed
Bertl,
Use of Saccharomyces cerevisiae for patch-clamp analysis of heterologous membrane proteins: characterization of Kat1, an inward-rectifying K+ channel from Arabidopsis thaliana, and comparison with endogeneous yeast channels and carriers.
1995,
Pubmed
,
Xenbase
Bezanilla,
Potassium conductance of the squid giant axon is modulated by ATP.
1986,
Pubmed
Bigger,
Sick sinus syndrome.
1979,
Pubmed
Chad,
The role of cyclic AMP-dependent phosphorylation in the maintenance and modulation of voltage-activated calcium channels.
1987,
Pubmed
Ciorba,
Modulation of potassium channel function by methionine oxidation and reduction.
1997,
Pubmed
,
Xenbase
Covarrubias,
Elimination of rapid potassium channel inactivation by phosphorylation of the inactivation gate.
1994,
Pubmed
,
Xenbase
Doroshenko,
Intracellular metabolism of adenosine 3',5'-cyclic monophosphate and calcium inward current in perfused neurones of Helix pomatia.
1982,
Pubmed
Drain,
Regulation of Shaker K+ channel inactivation gating by the cAMP-dependent protein kinase.
1994,
Pubmed
,
Xenbase
Fernandez,
Membrane patches and whole-cell membranes: a comparison of electrical properties in rat clonal pituitary (GH3) cells.
1984,
Pubmed
Forscher,
Modulation of calcium channels by norepinephrine in internally dialyzed avian sensory neurons.
1985,
Pubmed
Furukawa,
Functional linkage of the cardiac ATP-sensitive K+ channel to the actin cytoskeleton.
1996,
Pubmed
Gauss,
Molecular identification of a hyperpolarization-activated channel in sea urchin sperm.
1998,
Pubmed
Hedrich,
Inward rectifier potassium channels in plants differ from their animal counterparts in response to voltage and channel modulators.
1995,
Pubmed
,
Xenbase
Hilgemann,
Regulation of cardiac Na+,Ca2+ exchange and KATP potassium channels by PIP2.
1996,
Pubmed
Horn,
Prevention of rundown in electrophysiological recording.
1992,
Pubmed
Hoshi,
Regulation of voltage dependence of the KAT1 channel by intracellular factors.
1995,
Pubmed
,
Xenbase
Hoshi,
Biophysical and molecular mechanisms of Shaker potassium channel inactivation.
1990,
Pubmed
,
Xenbase
Kramer,
Patch cramming: monitoring intracellular messengers in intact cells with membrane patches containing detector ion channels.
1990,
Pubmed
Kupper,
Intracellular and extracellular amino acids that influence C-type inactivation and its modulation in a voltage-dependent potassium channel.
1995,
Pubmed
,
Xenbase
Levitan,
Modulation of ion channels by protein phosphorylation and dephosphorylation.
1994,
Pubmed
Li,
Functional modulation of brain sodium channels by cAMP-dependent phosphorylation.
1992,
Pubmed
Li,
Guard cells possess a calcium-dependent protein kinase that phosphorylates the KAT1 potassium channel.
1998,
Pubmed
Li,
Cyclic AMP stimulates K+ channel activity in mesophyll cells of Vicia faba L.
1994,
Pubmed
Ludwig,
A family of hyperpolarization-activated mammalian cation channels.
1998,
Pubmed
MacRobbie,
Signal transduction and ion channels in guard cells.
1998,
Pubmed
Marom,
Mechanism and modulation of inactivation of the Kv3 potassium channel.
1993,
Pubmed
,
Xenbase
Marten,
Voltage-dependent gating characteristics of the K+ channel KAT1 depend on the N and C termini.
1997,
Pubmed
Marten,
The N-terminus of the K channel KAT1 controls its voltage-dependent gating by altering the membrane electric field.
1998,
Pubmed
,
Xenbase
Marten,
Functional expression of the plant K+ channel KAT1 in insect cells.
1996,
Pubmed
,
Xenbase
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
Pape,
Queer current and pacemaker: the hyperpolarization-activated cation current in neurons.
1996,
Pubmed
Perozo,
Single channel studies of the phosphorylation of K+ channels in the squid giant axon. II. Nonstationary conditions.
1991,
Pubmed
Perozo,
Phosphorylation affects voltage gating of the delayed rectifier K+ channel by electrostatic interactions.
1990,
Pubmed
Rosenmund,
Calcium-induced actin depolymerization reduces NMDA channel activity.
1993,
Pubmed
Ruppersberg,
Regulation of fast inactivation of cloned mammalian IK(A) channels by cysteine oxidation.
1991,
Pubmed
,
Xenbase
Santoro,
Interactive cloning with the SH3 domain of N-src identifies a new brain specific ion channel protein, with homology to eag and cyclic nucleotide-gated channels.
1997,
Pubmed
Santoro,
Identification of a gene encoding a hyperpolarization-activated pacemaker channel of brain.
1998,
Pubmed
,
Xenbase
Schachtman,
Expression of an inward-rectifying potassium channel by the Arabidopsis KAT1 cDNA.
1992,
Pubmed
,
Xenbase
Spellberg,
Familial sinus node disease.
1971,
Pubmed
Véry,
Level of expression in Xenopus oocytes affects some characteristics of a plant inward-rectifying voltage-gated K+ channel.
1994,
Pubmed
,
Xenbase
Zei,
Voltage-dependent gating of single wild-type and S4 mutant KAT1 inward rectifier potassium channels.
1998,
Pubmed
,
Xenbase
