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We report here several unusual features of inactivation of the rat Kv2.1 delayed rectifier potassium channel, expressed in Xenopus oocytes. The voltage dependence of inactivation was U-shaped, with maximum inactivation near 0 mV. During a maintained depolarization, development of inactivation was slow and only weakly voltage dependent (tau = 4 s at 0 mV; tau = 7 s at +80 mV). However, recovery from inactivation was strongly voltage dependent (e-fold for 20 mV) and could be rapid (tau = 0.27 s at -140 mV). Kv2.1 showed cumulative inactivation, where inactivation built up during a train of brief depolarizations. A single maintained depolarization produced more steady-state inactivation than a train of pulses, but there could actually be more inactivation with the repeated pulses during the first few seconds. We term this phenomenon "excessive cumulative inactivation." These results can be explained by an allosteric model, in which inactivation is favored by activation of voltage sensors, but the open state of the channel is resistant to inactivation.
Aldrich,
Inactivation of delayed outward current in molluscan neurone somata.
1979, Pubmed
Aldrich,
Inactivation of delayed outward current in molluscan neurone somata.
1979,
Pubmed
Aldrich,
Mechanism of frequency-dependent broadening of molluscan neurone soma spikes.
1979,
Pubmed
Aldrich,
Inactivation of voltage-gated delayed potassium current in molluscan neurons. A kinetic model.
1981,
Pubmed
Armstrong,
Inactivation of the sodium channel. II. Gating current experiments.
1977,
Pubmed
Barry,
Differential expression of voltage-gated K+ channel subunits in adult rat heart. Relation to functional K+ channels?
1995,
Pubmed
Baukrowitz,
Use-dependent blockers and exit rate of the last ion from the multi-ion pore of a K+ channel.
1996,
Pubmed
Brahmajothi,
In situ hybridization reveals extensive diversity of K+ channel mRNA in isolated ferret cardiac myocytes.
1996,
Pubmed
Cahalan,
A voltage-gated potassium channel in human T lymphocytes.
1985,
Pubmed
Chabala,
The kinetics of recovery and development of potassium channel inactivation in perfused squid (Loligo pealei) giant axons.
1984,
Pubmed
Chandler,
Evidence for two types of sodium conductance in axons perfused with sodium fluoride solution.
1970,
Pubmed
Choi,
Tetraethylammonium blockade distinguishes two inactivation mechanisms in voltage-activated K+ channels.
1991,
Pubmed
De Biasi,
Inactivation determined by a single site in K+ pores.
1993,
Pubmed
DeCoursey,
State-dependent inactivation of K+ currents in rat type II alveolar epithelial cells.
1990,
Pubmed
DeCoursey,
Voltage-gated K+ channels in human T lymphocytes: a role in mitogenesis?
,
Pubmed
Demo,
The inactivation gate of the Shaker K+ channel behaves like an open-channel blocker.
1991,
Pubmed
Dixon,
Quantitative analysis of potassium channel mRNA expression in atrial and ventricular muscle of rats.
1994,
Pubmed
Dixon,
Potassium channel mRNA expression in prevertebral and paravertebral sympathetic neurons.
1996,
Pubmed
Drewe,
Distinct spatial and temporal expression patterns of K+ channel mRNAs from different subfamilies.
1992,
Pubmed
,
Xenbase
Eckert,
Inactivation of Ca channels.
1984,
Pubmed
Frech,
A novel potassium channel with delayed rectifier properties isolated from rat brain by expression cloning.
1989,
Pubmed
,
Xenbase
Furukawa,
Accumulation of inactivation in a cloned transient K+ channel (AKv1.1a) of Aplysia.
1995,
Pubmed
,
Xenbase
Gillespie,
The time course of sodium inactivation in squid giant axons.
1980,
Pubmed
Grissmer,
TEA prevents inactivation while blocking open K+ channels in human T lymphocytes.
1989,
Pubmed
HODGKIN,
A quantitative description of membrane current and its application to conduction and excitation in nerve.
1952,
Pubmed
Hoshi,
Biophysical and molecular mechanisms of Shaker potassium channel inactivation.
1990,
Pubmed
,
Xenbase
Hoshi,
Two types of inactivation in Shaker K+ channels: effects of alterations in the carboxy-terminal region.
1991,
Pubmed
,
Xenbase
Hoshi,
Shaker potassium channel gating. I: Transitions near the open state.
1994,
Pubmed
,
Xenbase
Huguenard,
Slow inactivation of a TEA-sensitive K current in acutely isolated rat thalamic relay neurons.
1991,
Pubmed
Ikeda,
Heterologous expression of the human potassium channel Kv2.1 in clonal mammalian cells by direct cytoplasmic microinjection of cRNA.
1992,
Pubmed
Jones,
Calcium currents in bullfrog sympathetic neurons. II. Inactivation.
1989,
Pubmed
Koren,
Gating mechanism of a cloned potassium channel expressed in frog oocytes and mammalian cells.
1990,
Pubmed
,
Xenbase
Kuo,
Na+ channels must deactivate to recover from inactivation.
1994,
Pubmed
Lee,
Temperature dependence of K(+)-channel properties in human T lymphocytes.
1990,
Pubmed
Levy,
Recovery from C-type inactivation is modulated by extracellular potassium.
1996,
Pubmed
Liu,
Dynamic rearrangement of the outer mouth of a K+ channel during gating.
1996,
Pubmed
López-Barneo,
Effects of external cations and mutations in the pore region on C-type inactivation of Shaker potassium channels.
1993,
Pubmed
,
Xenbase
MONOD,
ON THE NATURE OF ALLOSTERIC TRANSITIONS: A PLAUSIBLE MODEL.
1965,
Pubmed
Ma,
The role of K+ currents in frequency-dependent spike broadening in Aplysia R20 neurons: a dynamic-clamp analysis.
1996,
Pubmed
Marks,
Calcium currents in the A7r5 smooth muscle-derived cell line. An allosteric model for calcium channel activation and dihydropyridine agonist action.
1992,
Pubmed
Marom,
Mechanism and modulation of inactivation of the Kv3 potassium channel.
1993,
Pubmed
,
Xenbase
Marom,
State-dependent inactivation of the Kv3 potassium channel.
1994,
Pubmed
,
Xenbase
Mathes,
Fast inactivation of delayed rectifier K conductance in squid giant axon and its cell bodies.
1997,
Pubmed
Matteson,
K channels in T lymphocytes: a patch clamp study using monoclonal antibody adhesion.
,
Pubmed
McCormack,
A characterization of the activating structural rearrangements in voltage-dependent Shaker K+ channels.
1994,
Pubmed
Neher,
Properties of somatic membrane patches of snail neurons under voltage clamp.
1971,
Pubmed
Ogielska,
Cooperative subunit interactions in C-type inactivation of K channels.
1995,
Pubmed
,
Xenbase
Pak,
A mouse brain homolog of the Drosophila Shab K+ channel with conserved delayed-rectifier properties.
1991,
Pubmed
,
Xenbase
Panyi,
C-type inactivation of a voltage-gated K+ channel occurs by a cooperative mechanism.
1995,
Pubmed
Patlak,
Molecular kinetics of voltage-dependent Na+ channels.
1991,
Pubmed
Quattrocki,
A Shab potassium channel contributes to action potential broadening in peptidergic neurons.
1994,
Pubmed
,
Xenbase
Rasmusson,
C-type inactivation controls recovery in a fast inactivating cardiac K+ channel (Kv1.4) expressed in Xenopus oocytes.
1995,
Pubmed
,
Xenbase
Rasmusson,
Bi-stable block by 4-aminopyridine of a transient K+ channel (Kv1.4) cloned from ferret ventricle and expressed in Xenopus oocytes.
1995,
Pubmed
,
Xenbase
Ruppersberg,
Cloned neuronal IK(A) channels reopen during recovery from inactivation.
1991,
Pubmed
Schreibmayer,
Voltage clamping of Xenopus laevis oocytes utilizing agarose-cushion electrodes.
1994,
Pubmed
,
Xenbase
Shi,
Properties of Kv2.1 K+ channels expressed in transfected mammalian cells.
1994,
Pubmed
,
Xenbase
Shieh,
Role of transmembrane segment S5 on gating of voltage-dependent K+ channels.
1997,
Pubmed
,
Xenbase
Tillotson,
Inactivation of Ca conductance dependent on entry of Ca ions in molluscan neurons.
1979,
Pubmed
Trimmer,
Expression of Kv2.1 delayed rectifier K+ channel isoforms in the developing rat brain.
1993,
Pubmed
VanDongen,
Alteration and restoration of K+ channel function by deletions at the N- and C-termini.
1990,
Pubmed
Zagotta,
Voltage-dependent gating of Shaker A-type potassium channels in Drosophila muscle.
1990,
Pubmed
