Dynamic regulation of the voltage-gated Kv2.1 potassium channel by multisite phosphorylation.

@article{Mohapatra2007DynamicRO,
  title={Dynamic regulation of the voltage-gated Kv2.1 potassium channel by multisite phosphorylation.},
  author={Durga P. Mohapatra and K.-S. Park and James S. Trimmer},
  journal={Biochemical Society transactions},
  year={2007},
  volume={35 Pt 5},
  pages={
          1064-8
        }
}
Voltage-gated K(+) channels are key regulators of neuronal excitability. The Kv2.1 voltage-gated K(+) channel is the major delayed rectifier K(+) channel expressed in most central neurons, where it exists as a highly phosphorylated protein. Kv2.1 plays a critical role in homoeostatic regulation of intrinsic neuronal excitability through its activity- and calcineurin-dependent dephosphorylation. Here, we review studies leading to the identification and functional characterization of in vivo Kv2… 

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References

SHOWING 1-10 OF 35 REFERENCES
Graded Regulation of the Kv2.1 Potassium Channel by Variable Phosphorylation
TLDR
Mutations at multiple sites were additive, showing that variable phosphorylation of Kv2.1 at a large number of sites allows graded activity-dependent regulation of channel gating and neuronal firing properties.
Phosphorylation of the Kv2.1 K+ channel alters voltage-dependent activation.
TLDR
Parallel biochemical and electrophysiological results provide direct evidence that the voltage-dependent activation of the delayed-rectifier K+ channel Kv2.1 can be modulated by direct phosphorylation of the channel protein; such modulation of Kv 2.1 could dynamically regulate dendritic excitability.
Regulation of ion channel localization and phosphorylation by neuronal activity
TLDR
The finding that neuronal activity modifies the phosphorylation state, localization and function of Kv2.1 suggests an important link between excitatory neurotransmission and the intrinsic excitability of pyramidal neurons.
The Kv2.1 C Terminus Can Autonomously Transfer Kv2.1-Like Phosphorylation-Dependent Localization, Voltage-Dependent Gating, and Muscarinic Modulation to Diverse Kv Channels
TLDR
It is shown that the clustering and voltage-dependent gating of endogenous Kv2.1 in cultured rat hippocampal neurons are modulated by cholinergic stimulation, a common form of neuromodulation, and these findings provide novel mechanistic insights intoCholinergic modulation of ion channels and regulation of the localization and Voltage- dependent gating properties of the abundant neuronal Kv 2.1 channel.
Bidirectional Activity-Dependent Regulation of Neuronal Ion Channel Phosphorylation
TLDR
It is shown that in mammalian neurons, compared with other regulated sites, phosphorylation at S603 is supersensitive to calcineurin-mediated dephosphorylation in response to kainate-induced seizures in vivo, and brief glutamate stimulation of cultured hippocampal neurons.
Apoptotic surge of potassium currents is mediated by p38 phosphorylation of Kv2.1
TLDR
Electrophysiological and viability studies using Kv2.1 channel mutants identify a p38 phosphorylation site at Ser-800 (S800) that is required for Kv 2.1 membrane insertion, K+ current surge, and cell death, and remarkably, the absence of S800 phosphorylated is sufficient to prevent completion of the cell death program.
Identification of the Kv2.1 K+ Channel as a Major Component of the Delayed Rectifier K+ Current in Rat Hippocampal Neurons
TLDR
Together these studies show that Kv2.1, which is expressed at high levels in most mammalian central neurons, is a major contributor to the delayed rectifier K+ current in hippocampal neurons and that the KC antibody is a powerful tool for the elucidation of the role of the Kv 2.1 K+ channel in regulating neuronal excitability.
Calcium- and Metabolic State-Dependent Modulation of the Voltage-Dependent Kv2.1 Channel Regulates Neuronal Excitability in Response to Ischemia
TLDR
Evidence is provided that the localization and function of Kv2.1, the major somatodendritic delayed rectifier voltage-dependent K+ channel in central neurons, is regulated by hypoxia/ischemia-induced changes in metabolic state and intracellular Ca2+ levels and that dynamic modulation of IK/Kv1.2 could confer neuroprotection in response to brief ischemic insults.
Proteomic Analyses of Kv2.1 Channel Phosphorylation Sites Determining Cell Background-Specific Differences in Function
TLDR
The data presented here suggests that differential phosphorylation at a specific subset of sites, as opposed to utilization of novel cell-specific phosphorylated sites, can explain differences in the gating properties of Kv2.1 in different cell types under basal conditions.
...
1
2
3
4
...