Potassium Currents Expressed from Drosophila and Mouse eag cDNAs in Xenopus Oocytes

@article{Robertson1996PotassiumCE,
 title={Potassium Currents Expressed from Drosophila and Mouse eag cDNAs in Xenopus Oocytes},
 author={Gail A. Robertson and Jeffrey W. Warmke and Barry Ganetzky},
 journal={Neuropharmacology},
 year={1996},
 volume={35},
 pages={841-850},
 url={https://api.semanticscholar.org/CorpusID:9661356}
}

115 Citations

The Eag Family of K+ Channels in Drosophila and Mammals
Electrophysiological and pharmacological studies have provided evidence that HERG channels specify one component of the delayed rectifier, IKr, that contributes to the repolarization phase of cardiac action potentials.

Functional Analysis of a Mouse Brain Elk-Type K+Channel
A mouse gene is identified, Melk2, that encodes a predicted polypeptide with 48% amino acid identity to Drosophila Elk but only 40 and 36% identity with mouse Erg (Merg) and Eag (Meag), respectively, which should aid in identification of native counterparts to the Elk subfamily of channels in the nervous system.

Contribution of EAG to excitability and potassium currents in Drosophila larval motoneurons.
Results provide evidence that EAG represents a unique K(+) channel contributing to multiple K(+ currents in motoneurons helping to regulate excitability, consistent with previous observations in the Drosophila larval muscle.

Physiology of EAG K+ Channels
K channels form a large and diverse group of distinct ion channel families involved in a broad range of physiological functions (Pongs, 1992; Chandy & Gutman, 1995). This review concentrates on the...

CONTRIBUTIONS OF EAG PROTEIN TO NEURONAL EXCITABILITY IN IDENTIFIED THORACIC MOTONEURONS OF DROSOPHILA
EAG and Shal demonstrate a potential functional interaction and contribute to IA, and reduced EAG function with selective expression of eag double stranded RNAi transgene in motoneurons only suggests increased synaptic drive contributes to spontaneous events.

Differential Expression of Genes Encoding Subthreshold-Operating Voltage-Gated K+ Channels in Brain
The results show that each EAG subunit has a specific pattern of expression in rat brain, and indicates that the subthreshold current in many neurons may be complex, containing different components mediated by a number of channels with distinct properties and neuromodulatory responses.

Cloning and Functional Expression of Rat eag2, a New Member of the Ether-à-go-go Family of Potassium Channels and Comparison of Its Distribution with That of eag1
Heterologous expression of rat eag2 in HEK-293 cells gave rise to a voltage-gated, noninactivating potassium current, active at the cells' resting potential and blocked by low nanomolar concentrations of cytosolic calcium, likely to impart a modulation in membrane conductance, which is sensitively responsive to resting internal calcium, and levels of electrical activity.

Individual Subunits Contribute Independently to Slow Gating of Bovine EAG Potassium Channels*
The bovine ether à go-go gene encodes a delayed rectifier potassium channel, and it is shown that the slow gating, typical for EAG channels, is mediated by independent conformational transitions of individual subunits, which gain their voltage dependence from the S4 segment.

Characterization of Ether-à-go-go Channels Present in Photoreceptors Reveals Similarity to IKx, a K+ Current in Rod Inner Segments
Comparison of EAG currents with IKx, a noninactivating K+ current in the inner segment of rod photoreceptors, reveals an intriguing similarity, suggesting that EAG polypeptides are involved in the formation of Kx channels.
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36 References

Modulation of different K+ currents in Drosophila: a hypothetical role for the Eag subunit in multimeric K+ channels
The role of the eag subunit for modulating channels, as opposed to that of Sh subunits required for gating, selectivity, and conductance of the channel, suggest a combinatorial genetic framework for generating diversified K+ channels.

Ether-à-go-go encodes a voltage-gated channel permeable to K+ and Ca2+ and modulated by cAMP
The expression by eag RNA in Xenopus oocytes of such a channel which incorporates properties of both voltage- and ligand-gated channels is reported, likely to be important in the modulation of synaptic efficiency in both central and peripheral nervous systems.

Functional expression of a rat homologue of the voltage gated either á go‐go potassium channel reveals differences in selectivity and activation kinetics between the Drosophila channel and its mammalian counterpart.
Cloned a mammalian (rat) homologue of Drosophila ether á go‐go (eag) cDNA, which encodes a distinct type of voltage activated potassium (K) channel, which may have important implications in neural signal transduction allowing neurons to tune their repolarizing properties in response to membrane hyperpolarization.

A family of potassium channel genes related to eag in Drosophila and mammals.
A conserved family of genes related to Drosophila eag, which encodes a distinct type of voltage-activated K+ channel, which is most closely related to vertebrate cyclic nucleotide-gated cation channels and plant inward-rectifying K+ channels is identified.

Expression of an inward-rectifying potassium channel by the Arabidopsis KAT1 cDNA.
It is shown that a single messenger RNA transcript from the Arabidopsis thaliana KAT1 complementary DNA confers the functional expression of a hyperpolarization-activated K+ channel in Xenopus oocytes.

Voltage-dependent gating of Shaker A-type potassium channels in Drosophila muscle
The voltage-dependent gating mechanism of A1-type potassium channels coded for by the Shaker locus of Drosophila was studied and it was concluded that all of the molecular transitions after first opening, including the inactivation transition, are voltage independent and therefore not associated with charge movement through the membrane.

Alteration of four identified K+ currents in Drosophila muscle by mutations in eag
Results suggest that the eag locus encodes a subunit common to different potassium channels, and combinatorial assembly of polypeptides from different genes may contribute to potassium channel diversity.

A distinct potassium channel polypeptide encoded by the Drosophila eag locus
Many of the signaling properties of neurons and other electrically excitable cells are determined by a diverse family of potassium channels. A number of genes that encode potassium channel...

The inward rectification mechanism of the HERG cardiac potassium channel
The characteristics of this gating suggest a specific role for this channel in the normal suppression of arrhythmias, and the inactivation gating mechanism resembles that of C-type inactivation of K+ channels.

Functional expression of a probable Arabidopsis thaliana potassium channel in Saccharomyces cerevisiae.
The isolation of a cDNA from Arabidopsis thaliana that encodes a probable K+ channel and the results suggest that the structural motif for K+ channels has been conserved between plants and animals.