Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.11.26 (GSK)
 6,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Herein we describe three applications of label-free kinase profiling using a novel type of phosphate affinity polyacrylamide gel electrophoresis. The phosphate affinity site is a polyacrylamide-bound dinuclear Mn2+ complex that enables the mobility shift detection of phosphorylated proteins from their nonphosphorylated counterpart. The first application is in vitro kinase activity profiling for the analysis of varied phosphoprotein isotypes in phosphorylation status. The activity profiles of six kinds of kinases, glycogen synthase kinase-3beta, cyclin-dependent kinase 5/p35, protein kinase A, mitogen-activated protein kinase (MAPK), casein kinase II, and calmodulin-dependent protein kinase II, were determined using a substrate protein, Tau, which has a number of phosphorylation sites. Each kinase demonstrated characteristic multiple electrophoresis migration bands up-shifted from the nonphosphorylated Tau due to differences in the phosphorylation sites and stoichiometry. The second application is in vivo kinase activity profiling for the analysis of protein phosphorylation involved in intracellular signal transduction. The time course changes in the epidermal growth factor-induced phosphorylation levels of Shc and MAPK in A431 cells were visualized as highly up-shifted migration bands by subsequent immunoblotting with anti-Shc and anti-MAPK antibodies. The third application is in vitro kinase inhibition profiling for the quantitative screening of kinase-specific inhibitors. The inhibition profile of a tyrosine kinase, Abl (a histidine-tagged recombinant mouse Abl kinase), was determined using the substrate Abltide-GST (a fusion protein consisting of a specific substrate peptide for Abl and glutathione S-transferase) and the approved drug Glivec (an ATP competitor). In the kinase assay, the slower migration band, monophosphorylated Abltide-GST, increased time-dependently, whereas the faster migration band, nonphosphorylated Abltide-GST, decreased. The dose-dependent inhibition of Glivec was determined by a change in the ratio of the faster and slower migration bands, which showed an IC50 value of 1.6 microM in the presence of 0.10 mM ATP.
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PMID:Label-free kinase profiling using phosphate affinity polyacrylamide gel electrophoresis. 1708 64

Cancer is a multi-step process, one of the latest events correspond to metastasis formation and dissemination, to date the major cause of deaths. The h-prune-nm23-H1 protein complex and its activation of PDE-cAMP activity have been shown to correlate with breast cancer progression and metastasis formation. Here, we describe the protein complex formation and its involvement in cell migration. By gene expression studies and protein-protein pull-down analyses coupled to mass spectrometry we have identified new genes and pathways along which the h-prune-nm23-H1 complex exerts its function. We review here h-prune binding to the glycogen synthase kinase (GSK-3beta) and identify a new h-prune protein partner, Gelsolin, an ATP severing protein acting in focal adhesions, in a MDA-435 breast cancer cellular model. The results presented here underline the importance of this protein complex leading to new translational studies involved into the inhibition of cell migration, thus enhancing the potential of using this knowledge to direct inhibition of metastases formation in humans.
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PMID:H-prune-nm23-H1 protein complex and correlation to pathways in cancer metastasis. 1710 19

Novel bis(indolyl)maleimide pyridinophanes 3, 9a, 9b, 10a, 10b, and 11 were prepared by cobalt-mediated [2+2+2] cycloaddition of an appropriate alpha,omega-diyne with an N,N-dialkylcyanamide. These macrocyclic heterophanes were found to be potent, selective inhibitors of glycogen synthase kinase-3beta. An X-ray structure of a co-crystal of GSK-3beta and 3 (IC(50)=3nM) depicts the hydrogen bonding and hydrophobic interactions in the ATP-binding pocket of this serine/threonine protein kinase.
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PMID:Novel bis(indolyl)maleimide pyridinophanes that are potent, selective inhibitors of glycogen synthase kinase-3. 1735 Feb 61

Lithium is a therapeutic agent commonly used to treat bipolar disorder and its beneficial effects are thought to be due to a combination of activation of the Wnt/beta-catenin pathway via inhibition of glycogen synthase kinase-3beta and depletion of the inositol pool via inhibition of the inositol monophosphatase-1. We demonstrated that lithium in primary endothelial cells induced an increase in mitochondrial mass leading to an increase in ATP production without any significant change in mitochondrial efficiency. This increase in mitochondrial mass was associated with an increase in the mRNA levels of mitochondrial biogenesis transcription factors: nuclear respiratory factor-1 and -2beta, as well as mitochondrial transcription factors A and B2, which lead to the coordinated upregulation of oxidative phosphorylation components encoded by either the nuclear or mitochondrial genome. These effects of lithium on mitochondrial biogenesis were independent of the inhibition of glycogen synthase kinase-3beta and independent of inositol depletion. Also, expression of the coactivator PGC-1alpha was increased, whereas expression of the coactivator PRC was not affected. Lithium treatment rapidly induced a decrease in activating Akt-Ser473 phosphorylation and inhibitory Forkhead box class O (FOXO1)-Thr24 phosphorylation, as well as an increase in activating c-AMP responsive element binding (CREB)-Ser133 phosphorylation, two mechanisms known to control PGC-1alpha expression. Together, our results show that lithium induces mitochondrial biogenesis via CREB/PGC-1alpha and FOXO1/PGC-1alpha cascades, which highlight the pleiotropic effects of lithium and reveal also novel beneficial effects via preservation of mitochondrial functions.
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PMID:Lithium increases PGC-1alpha expression and mitochondrial biogenesis in primary bovine aortic endothelial cells. 1745 29

Among the numerous effects of lithium on intracellular targets, its possible action on mitochondria remains poorly explored. In the experiments with suspension of isolated brain mitochondria, replacement of KCl by LiCl suppressed mitochondrial swelling, depolarization, and a release of cytochrome c induced by a single Ca2+ bolus. Li+ robustly protected individual brain mitochondria loaded with rhodamine 123 against Ca2+-induced depolarization. In the experiments with slow calcium infusion, replacement of KCl by LiCl in the incubation medium increased resilience of synaptic and nonsynaptic brain mitochondria as well as resilience of liver and heart mitochondria to the deleterious effect of Ca2+. In LiCl medium, mitochondria accumulated larger amounts of Ca2+ before they lost the ability to sequester Ca2+. However, lithium appeared to be ineffective if mitochondria were challenged by Sr2+ instead of Ca2+. Cyclosporin A, sanglifehrin A, and Mg2+, inhibitors of the mitochondrial permeability transition (mPT), increased mitochondrial Ca2+ capacity in KCl medium but failed to do so in LiCl medium. This suggests that the mPT might be a common target for Li+ and mPT inhibitors. In addition, lithium protected mitochondria against high Ca2+ in the presence of ATP, where cyclosporin A was reported to be ineffective. SB216763 and SB415286, inhibitors of glycogen synthase kinase-3beta, which is implicated in regulating reactive oxygen species-induced mPT in cardiac mitochondria, did not increase Ca2+ capacity of brain mitochondria. Altogether, these findings suggest that Li+ desensitizes mitochondria to elevated Ca2+ and diminishes cytochrome c release from brain mitochondria by antagonizing the Ca2+-induced mPT.
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PMID:Lithium desensitizes brain mitochondria to calcium, antagonizes permeability transition, and diminishes cytochrome C release. 1748 18

Ischemic preconditioning renders the heart resistant to infarction from ischemia/reperfusion. Over the past two decades a great deal has been learned about preconditioning's mechanism. Adenosine, bradykinin, and opioids act in parallel to trigger the preconditioned state and do so by activating PKC. While adenosine couples directly to PKC through the phospholipases, bradykinin and opioids do so through a complex pathway that includes in order: phosphatidylinositol 3-kinase (PI3-kinase), Akt, nitric oxide synthase, guanylyl cyclase, PKG, opening of mitochondrial K(ATP) channels, and activation of PKC by redox signaling. There are even differences between the opioid and bradykinin coupling as the former activates PI3-kinase through transactivation of the epidermal growth factor receptor while the latter has an unknown coupling mechanism. Protection stems from inhibition of formation of mitochondrial permeability transition pores early in reperfusion through activation of the survival kinases, Akt and ERK. These kinases are activated as a result of PKC somehow promoting signaling from adenosine A(2) receptors early in reperfusion. The survival kinases are thought to inhibit pore formation by phosphorylating GSK-3beta. The reperfused heart requires the support of the protective signals for only about an hour after which the ischemic injury is repaired and the signals are no longer needed.
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PMID:Signaling pathways in ischemic preconditioning. 1751 69

The cardiac glycoside ouabain initiates a cascade of signaling events through Na+,K+-ATPase, leading to an increase in cell growth and proliferation in different cell types. We explored the effects of ouabain on glucose metabolism in skeletal muscle and clarified the mechanisms of ouabain signal transduction. In rat soleus muscle 200 microM ouabain decreased basal glucose uptake without effect on insulin-stimulated glucose uptake. Ouabain increased glycogen synthesis additively to insulin and this effect was abolished in the presence of a MEK1/2 inhibitor (PD98059) or a c-Src inhibitor (PP2). Ouabain exposure reduced glucose oxidation, and this effect was reversed in the presence of PP2. Incubation with ouabain did not affect intramuscular ATP and its metabolites; however acetyl-CoA carboxylase phosphorylation was reduced, with no effect on AMPK phosphorylation. Insulin-stimulated Akt phosphorylation was not affected by ouabain. Ouabain reduced basal and insulin-stimulated phosphorylation of PKC alpha/beta and delta isoforms, whereas phosphorylation of PKCzeta was unchanged. Ouabain exposure increased interaction of 1- and 2-subunits of Na-pump with c-Src, as assessed by co-immunoprecipitation with c-Src. Phosphorylation of ERK1/2, GSK 3 / and p90rsk activity was increased in response to ouabain, and these effects were prevented in the presence of PD98059 and PP2. In conclusion, the cardiac glycoside ouabain stimulates glycogen synthesis additively to insulin in rat skeletal muscle. This effect is mediated by activation of c-Src-, ERK1/2- p90rsk- and GSK3-dependent signaling pathway.
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PMID:Metabolic and signaling events mediated by cardiotonic steroid ouabain in rat skeletal muscle. 1753 36

A hydroxy functional group was introduced as the hydrogen bond donor and acceptor at the hinge region of protein kinase in order to develop novel ATP-competitive inhibitors. Several derivatives of 7-hydroxyl-1H-benzoimidazole were designed as inhibitors of glycogen synthase kinase-3beta with the help of ab initio calculations and a docking study. Enzymatic assay and an X-ray complex study showed that these designed compounds were highly potent ATP-competitive inhibitors.
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PMID:Design and synthesis of 7-hydroxy-1H-benzoimidazole derivatives as novel inhibitors of glycogen synthase kinase-3beta. 1776 34

The 2,4-disubstituted thiadiazolidinones (TDZD) were described as the first non-ATP competitive GSK-3beta inhibitors. New modifications in this heterocyclic ring are here reported to study the influence on the biological activity. The basic skeleton of 1,2,4-thiadiazole and also one of the carbonyl groups are kept, while different modifications are introduced in positions 3 and 5, respectively. The GSK-3beta activity of the new thiadiazole derivatives here synthesized showed IC(50) values for some of the compounds in the micromolar range. Additionally, ATP competition studies have been carried out, showing that as well as the first generation of TDZD, these new compounds act in a non-competitive manner. With this study, additional requirements for the biological activity of the TDZD family have been delineated.
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PMID:Non-ATP competitive glycogen synthase kinase 3beta (GSK-3beta) inhibitors: study of structural requirements for thiadiazolidinone derivatives. 1791 14

Within the histopathology of Alzheimer's disease (AD) certain hallmarks are beeing observed. The occurance of protein deposits belong to such characteristic features. Such deposits can be found extracellular as beta-amyloid (Abeta) plaques and intracellular as neurofibrillary tangles (NFTs). In the search for novel AD therapeutics it became of great interest to investigate the formation of NFTs and their contribution to the AD symptomatic. NFTs consist of hyperphosphorylated tau protein. Within the phosphorylation process of tau protein two kinases are of great importance: cyclin dependent kinase 5 (cdk5) and its truncated regulatory subunit p25 and glycogen synthase kinase 3beta (GSK-3beta). The role of both kinases within the NFT formation process is still under debate. To better understand the pathophysiological process highly selective inhibitors of both kinases are of value. Known inhibitors lack the necessary selectivity. We developed novel 1-aza-9-oxafluo-renes as selective GSK-3beta inhibitors. Structure-activity relationships of a series of 4-phenyl substituted derivatives are discussed. Variation of the 3-side chain led to selective carbonyl amide derivatives with selectivity factors of more than 100 at the tested ATP competitor concentrations. Such selectivities permit specific investigation of the role of GSK-3beta within the NFT formation processes.
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PMID:Probing novel 1-aza-9-oxafluorenes as selective GSK-3beta inhibitors. 1800 Sep 38


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