K+ channel activation by all three isoforms of serum- and glucocorticoid-dependent protein kinase SGK

@article{Gamper2002KCA,
  title={K+ channel activation by all three isoforms of serum- and glucocorticoid-dependent protein kinase SGK},
  author={Nikita Gamper and Sophie A. Fillon and Y. Feng and Bj{\"o}rn Friedrich and Paul Lang and Guido Henke and Stephan M Huber and T. Kobayashi and Philip Cohen and Florian Lang},
  journal={Pfl{\"u}gers Archiv},
  year={2002},
  volume={445},
  pages={60-66}
}
Abstract. The serum- and glucocorticoid-dependent kinase SGK1 was originally identified as a glucocorticoid-sensitive gene. Subsequently, the two homologous kinases SGK2 and SGK3 have been cloned, being products of distinct genes, which are differentially expressed and share 80% identity in amino acid sequence in their catalytic domains. While SGK1 has been shown to activate ion channels, including K+ channels, the functions of SGK2 and SGK3 have not been examined. The present study was… 
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TLDR
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TLDR
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TLDR
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References

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TLDR
Two novel isoforms of SGK are identified, termed SGK2 and SGK3, whose catalytic domains share 80% amino acid sequence identity with each other and with SGK (renamed SGK1), and are activated in vitro by PDK1 and in vivo in response to signals that activate phosphatidylinositol (PI) 3-kinase.
The Serum and Glucocorticoid Kinase sgk Increases the Abundance of Epithelial Sodium Channels in the Plasma Membrane of Xenopus Oocytes*
TLDR
The experiments indicate that sgk stimulates electrogenic sodium transport by increasing the number of ENaCs at the cell surface and suggest that s gk may mediate the early increase in aldosterone-induced sodium current.
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TLDR
This is the first report of a presumed serine/threonine protein kinase that is highly regulated at the transcriptional level by glucocorticoid hormones and suggests a novel interplay between glucoc Corticoid receptor signalling and aprotein kinase of the second messenger family.
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TLDR
It is reported here that aldosterone rapidly increases mRNA levels of a putative Ser/Thr kinase,sgk (or serum- andglucocorticoid-regulated kinase), in its native target cells, i.e. in cortical collecting duct cells, and this protein kinase plays an important role in the early phase of ald testosterone-stimulated Na+ transport.
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TLDR
Sgk (serum and glucocorticoid-regulated kinase), a member of the serine-threonine kinase family, is identified as an aldosterone-induced regulator of ENaC activity, suggesting that sgk plays a central role in ald testosterone regulation of Na+ absorption and thus in the control of extracellular fluid volume, blood pressure, and sodium homeostasis.
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TLDR
SGK regulates epithelial Na+ absorption in part by modulating the function of hNedd4-2 by phosphorylation and a PY motif in SGK mediated the interaction and was required for SGK to stimulate ENaC.
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TLDR
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TLDR
Co-expression studies in Xenopus laevis oocytes revealed that SGK1 markedly increased the activity of the neuronal K+ channel Kv1.3 as activation of K+ channels modifies excitation of neuronal cells,SGK1 may participate in the regulation of neuronal excitability.
IGF-1 up-regulates K+ channels via PI3-kinase, PDK1 and SGK1
TLDR
In conclusion, IGF-1 through PI3-kinase, PDK1 and SGK1 up-regulates Kv channels, an effect required for the proliferative action of the growth factor.
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TLDR
It is shown that a mouse cytotoxic T-lymphocyte line, CTLL-2, is devoid of voltage-dependent K+ channels and is unable toVolume regulate, and transient transfection of these cells with Kv1.3 reconstitutes their ability to volume regulate.
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