Regulation and Physiological Roles of Serum- and Glucocorticoid-Induced Protein Kinase Isoforms

@article{Lang2001RegulationAP,
  title={Regulation and Physiological Roles of Serum- and Glucocorticoid-Induced Protein Kinase Isoforms},
  author={Florian Lang and Philip Cohen},
  journal={Science's STKE},
  year={2001},
  volume={2001},
  pages={re17 - re17}
}
Serum- and glucocorticoid-induced protein kinase 1 (SGK1) was identified in 1993 as an immediate early gene whose mRNA levels increase dramatically within 30 minutes when cells are exposed to serum or glucocorticoids, or both. Subsequently, many other agonists, acting through a variety of signal transduction pathways, have been shown to induce SGK1 gene transcription in cells and tissues. SGK1 is a member of the "AGC" subfamily, which includes protein kinases A, G, and C, and its catalytic… 
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TLDR
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TLDR
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TLDR
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PDK1, the master regulator of AGC kinase signal transduction.
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References

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Characterization of the structure and regulation of two novel isoforms of serum- and glucocorticoid-induced protein kinase.
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.
Activation of Serum- and Glucocorticoid-induced Protein Kinase (Sgk) by Cyclic AMP and Insulin*
TLDR
It is demonstrated that incubation of transfected cells with 8-(4-chlorophenylthio)-cAMP led to a 2-fold activation of recombinant Sgk expressed in COS7 cells, and the combination of insulin plus 8CPT-cAMP elicited a larger response than either agent alone.
Serum and glucocorticoid‐inducible kinase (SGK) is a target of the PI 3‐kinase‐stimulated signaling pathway
TLDR
Evidence is presented that SGK is a component of the phosphoinositide 3 (PI 3)‐kinase signaling pathway and that hyperphosphorylation of endogenous SGK, and promoted translocation to the nucleus could be inhibited by wortmannin, but not by rapamycin.
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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.
Activation of serum- and glucocorticoid-regulated protein kinase by agonists that activate phosphatidylinositide 3-kinase is mediated by 3-phosphoinositide-dependent protein kinase-1 (PDK1) and PDK2.
TLDR
It is shown that PDK1 activates SGK in vitro by phosphorylating Thr256, and the findings raise the possibility that some physiological roles ascribed to PKB on the basis of the overexpression of constitutively active PKB mutants might be mediated by SGK.
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TLDR
The novel, biphasic induction of sgk that correlates with granulosa cell progression from proliferation to differentiation appears to involve sequential, coordinated actions of FSH, PKA, and transcription factors, including Sp1 and Sp3.
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TLDR
Results show that FSH and LH stimulate marked increases in the cellular content of Sgk, as well as dramatic changes in the subcellular distribution of this kinase.
Hyperosmotic Stress Stimulates Promoter Activity and Regulates Cellular Utilization of the Serum- and Glucocorticoid-inducible Protein Kinase (Sgk) by a p38 MAPK-dependent Pathway*
TLDR
It is proposed that the stimulated expression of enzymatically active Sgk after sorbitol treatment is a newly defined component of the p38 MAPK-mediated response to hyperosmotic stress.
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