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Sample records for syk kinase smtk4

  1. Shiga Toxin Increases Formation of Clathrin-Coated Pits through Syk Kinase

    DEFF Research Database (Denmark)

    Utskarpen, Audrun; Massol, Ramiro; van Deurs, Bo

    2010-01-01

    with Stx results in an increase in the number of clathrin-coated profiles as determined by electron microscopy and on the number of structures containing the endocytic AP-2 adaptor at the plasma membrane determined by live-cell spinning disk confocal imaging. These responses to Stx require functional Syk...... activates signaling through the tyrosine kinase Syk. We previously described that Syk activity is important for Stx entry, but it remained unclear how this kinase modulates endocytosis of Stx. Here we characterized the effects of Stx and Syk on clathrin-coated pit formation. We found that acute treatment...... activity. We propose that a signaling pathway mediated by Syk and modulated by Stx leads to an increased number of endocytic clathrin-coated structures, thus providing a possible mechanism by which Stx enhances its own endocytosis....

  2. Aspirin Augments IgE-Mediated Histamine Release from Human Peripheral Basophils via Syk Kinase Activation

    Directory of Open Access Journals (Sweden)

    Hiroaki Matsuo

    2013-01-01

    Conclusions: Aspirin enhanced histamine release from basophils via increased Syk kinase activation, and that the augmentation of histamine release by NSAIDs or FAs may be one possible cause of worsening symptoms in patients with chronic urticaria and FDEIA.

  3. The Src, Syk, and Tec family kinases: distinct types of molecular switches.

    Science.gov (United States)

    Bradshaw, J Michael

    2010-08-01

    The Src, Syk, and Tec family kinases are three of the most well characterized tyrosine kinase families found in the human genome. Members of these kinase families function downstream of antigen and F(c) receptors in hematopoietic cells and transduce signals leading to calcium mobilization, altered gene expression, cytokine production, and cell proliferation. Over the last several years, structural and biochemical studies have begun to uncover the molecular mechanisms regulating activation of these kinases. It appears that each kinase family functions as a distinct type of molecular switch. This review discusses the activation of the Src, Syk, and Tec kinases from the perspective of structure, phosphorylation, allosteric regulation, and kinetics. The multiple factors that regulate the Src, Syk, and Tec families illustrate the important role played by each of these kinases in immune cell signaling.

  4. Differential Requirements for Src-Family Kinases in SYK or ZAP70-Mediated SLP-76 Phosphorylation in Lymphocytes.

    Science.gov (United States)

    Fasbender, Frank; Claus, Maren; Wingert, Sabine; Sandusky, Mina; Watzl, Carsten

    2017-01-01

    In a synthetic biology approach using Schneider (S2) cells, we show that SLP-76 is directly phosphorylated at tyrosines Y113 and Y128 by SYK in the presence of ITAM-containing adapters such as CD3ζ, DAP12, or FcεRγ. This phosphorylation was dependent on at least one functional ITAM and a functional SH2 domain within SYK. Inhibition of Src-kinases by inhibitors PP1 and PP2 did not reduce SLP-76 phosphorylation in S2 cells, suggesting an ITAM and SYK dependent, but Src-kinase independent signaling pathway. This direct ITAM/SYK/SLP-76 signaling pathway therefore differs from previously described ITAM signaling. However, the SYK-family kinase ZAP70 required the additional co-expression of the Src-family kinases Fyn or Lck to efficiently phosphorylate SLP-76 in S2 cells. This difference in Src-family kinase dependency of SYK versus ZAP70-mediated ITAM-based signaling was further demonstrated in human lymphocytes. ITAM signaling in ZAP70-expressing T cells was dependent on the activity of Src-family kinases. In contrast, Src-family kinases were partially dispensable for ITAM signaling in SYK-expressing B cells or in natural killer cells, which express SYK and ZAP70. This demonstrates that SYK can signal using a Src-kinase independent ITAM-based signaling pathway, which may be involved in calibrating the threshold for lymphocyte activation.

  5. Complement receptor-3 negatively regulates the phagocytosis of degenerated myelin through tyrosine kinase Syk and cofilin

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    Hadas Smadar

    2012-07-01

    Full Text Available Abstract Background Intact myelin, which normally surrounds axons, breaks down in Wallerian degeneration following axonal injury and during neurodegenerative diseases such as multiple sclerosis. Clearance of degenerated myelin by phagocytosis is essential since myelin impedes repair and exacerbates damage. CR3 (complement receptor-3 is a principal phagocytic receptor in myelin phagocytosis. We studied how tyrosine kinase Syk (spleen tyrosine kinase and cofilin control phagocytosis of degenerated myelin by CR3 in microglia and macrophages. Syk is a non-receptor tyrosine kinase that CR3 recruits to convey cellular functions. Cofilin is an actin-depolymerizing protein that controls F-actin (filamentous actin remodeling (i.e., disassembly and reassembly by shifting between active unphosphorylated and inactive phosphorylated states. Results Syk was continuously activated during prolonged phagocytosis. Phagocytosis increased when Syk activity and expression were reduced, suggesting that normally Syk down regulates CR3-mediated myelin phagocytosis. Levels of inactive p-cofilin (phosphorylated cofilin decreased transiently during prolonged phagocytosis. In contrast, p-cofilin levels decreased continuously when Syk activity and expression were continuously reduced, suggesting that normally Syk advances the inactive state of cofilin. Observations also revealed inverse relationships between levels of phagocytosis and levels of inactive p-cofilin, suggesting that active unphosphorylated cofilin advances phagocytosis. Active cofilin could advance phagocytosis by promoting F-actin remodeling, which supports the production of membrane protrusions (e.g., filopodia, which, as we also revealed, are instrumental in myelin phagocytosis. Conclusions CR3 both activates and downregulates myelin phagocytosis at the same time. Activation was previously documented. We presently demonstrate that downregulation is mediated through Syk, which advances the inactive

  6. Cholesterol crystals activate Syk and PI3 kinase in human macrophages and dendritic cells.

    Science.gov (United States)

    Corr, Emma M; Cunningham, Clare C; Dunne, Aisling

    2016-08-01

    Cholesterol crystals are a key component of atherosclerotic lesions where they promote pro-inflammatory cytokine production and plaque destabilization. Antagonists of inflammatory mediators and agents that dissolve or prevent the formation of cholesterol crystals are being explored as potential therapeutics for atherothrombosis. We sought to identify signalling molecules activated following exposure of immune cells to cholesterol crystals with the view to identifying novel therapeutic targets. Human macrophages and dendritic cells (DC) were exposed to cholesterol crystals and activation of signalling molecules was assessed by immunoblotting. The role of Syk and PI3K in crystal-induced interleukin (IL)-1 production was determined by ELISA using specific kinase inhibitors. Real-time PCR was employed to examine the role of Syk/PI3K in cholesterol crystal-induced expression of S100 proteins and MMPs. Exposure of human macrophages and DC to cholesterol crystals induced robust activation of Syk and PI3K within 2-5 min. Pharmacological inhibition of Syk/PI3K reduced crystal-induced IL-1α/β production by approximately 80%. Activation of the downstream MAP kinases, MEK and ERK, was suppressed following inhibition of Syk and PI3K. Finally, inhibition of both Syk and PI3K significantly reduced cholesterol crystal-induced S100A8 and MMP1 gene expression by >70% while inhibition of PI3K also reduced S100A12 expression. Cholesterol crystals activate specific cell signalling pathways which drive the production of inflammatory cytokines and degradative enzymes known to contribute to disease initiation and progression. These molecular events are dependent on activation of Syk and PI3K, hence, they represent potential therapeutic targets for the treatment of cholesterol crystal-related pathologies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Peptidomimetic ligands for the tandem SH2 domain of Syk kinase

    NARCIS (Netherlands)

    Kuil, J.|info:eu-repo/dai/nl/323359086

    2009-01-01

    The Spleen tyrosine kinase (Syk) protein functions as a switch in a number of receptor signaling cascades. One of these cascades is the high affinity IgE receptor (Fc?RI) signaling pathway. Fc?RI consists of an ?-, ?- and two ?-chains. The ?- and ?-chains have intracellular an Immunoreceptor

  8. Phosphatidylinositol-3-kinase-dependent phosphorylation of SLP-76 by the lymphoma-associated ITK-SYK fusion-protein

    International Nuclear Information System (INIS)

    Hussain, Alamdar; Faryal, Rani; Nore, Beston F.; Mohamed, Abdalla J.; Smith, C.I. Edvard

    2009-01-01

    Recurrent chromosomal translocations have long been implicated in various types of lymphomas and other malignancies. Novel recurrent t(5;9)(q33;q22) has been recently discovered in un-specified peripheral T-cell lymphoma. To elucidate the role of this translocation, the corresponding fusion construct encoding the N-terminal portion of the ITK kinase and the C-terminal catalytic region of the SYK kinase was generated. We herein show that the ITK-SYK fusion-protein is constitutively active. Moreover, we demonstrate that ITK-SYK is phosphorylated on key tyrosine residues and is capable of potently phosphorylating the related adapter proteins BLNK and SLP-76. In transiently transfected cells, SYK was phosphorylated at Y352 but not detectably at the activation-loop tyrosines Y525/Y526. In contrast, ITK-SYK was phosphorylated both at Y212 and the activation-loop tyrosines Y385/Y386, corresponding to Y352 and Y525/Y526 in SYK, respectively. In resting primary lymphocytes, ITK-SYK predominantly localizes to the cell surface. In addition, we demonstrate that following stimulation, the ITK-SYK fusion-protein in cell lines translocates to the cell membrane and, moreover, that this phenomenon as well as SLP-76 phosphorylation are blocked upon phosphatidylinositol-3-kinase (PI3-kinase) inhibition.

  9. Regulation of Discrete Functional Responses by Syk and Src Family Tyrosine Kinases in Human Neutrophils

    Directory of Open Access Journals (Sweden)

    Thornin Ear

    2017-01-01

    Full Text Available Neutrophils play a critical role in innate immunity and also influence adaptive immune responses. This occurs in good part through their production of inflammatory and immunomodulatory cytokines, in conjunction with their prolonged survival at inflamed foci. While a picture of the signaling machinery underlying these neutrophil responses is now emerging, much remains to be uncovered. In this study, we report that neutrophils constitutively express various Src family isoforms (STKs, as well as Syk, and that inhibition of these protein tyrosine kinases selectively hinders inflammatory cytokine generation by acting posttranscriptionally. Accordingly, STK or Syk inhibition decreases the phosphorylation of signaling intermediates (e.g., eIF-4E, S6K, and MNK1 involved in translational control. By contrast, delayed apoptosis appears to be independent of either STKs or Syk. Our data therefore significantly extend our understanding of which neutrophil responses are governed by STKs and Syk and pinpoint some signaling intermediates that are likely involved. In view of the foremost role of neutrophils in several chronic inflammatory conditions, our findings identify potential molecular targets that could be exploited for future therapeutic intervention.

  10. Carboxamide Spleen Tyrosine Kinase (Syk) Inhibitors: Leveraging Ground State Interactions To Accelerate Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, J. Michael; Altman, Michael D.; Cash, Brandon; Haidle, Andrew M.; Kubiak, Rachel L.; Maddess, Matthew L.; Yan, Youwei; Northrup, Alan B. (Merck)

    2016-12-08

    Optimization of a series of highly potent and kinome selective carbon-linked carboxamide spleen tyrosine kinase (Syk) inhibitors with favorable drug-like properties is described. A pervasive Ames liability in an analogous nitrogen-linked carboxamide series was obviated by replacement with a carbon-linked moiety. Initial efforts lacked on-target potency, likely due to strain induced between the hinge binding amide and solvent front heterocycle. Consideration of ground state and bound state energetics allowed rapid realization of improved solvent front substituents affording subnanomolar Syk potency and high kinome selectivity. These molecules were also devoid of mutagenicity risk as assessed via the Ames test using the TA97a Salmonella strain.

  11. Nonredundant roles of Src-family kinases and Syk in the initiation of B-cell antigen receptor signaling

    Czech Academy of Sciences Publication Activity Database

    Štěpánek, Ondřej; Dráber, Peter; Drobek, Aleš; Hořejší, Václav; Brdička, Tomáš

    2013-01-01

    Roč. 190, č. 4 (2013), s. 1807-1818 ISSN 0022-1767 R&D Projects: GA ČR(CZ) GBP302/12/G101; GA ČR GAP302/12/1712 Institutional support: RVO:68378050 Keywords : BCR signaling * Src family kinases * Syk Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.362, year: 2013

  12. Involvement of Syk kinase in TNF-induced nitric oxide production by airway epithelial cells

    International Nuclear Information System (INIS)

    Ulanova, Marina; Marcet-Palacios, Marcelo; Munoz, Samira; Asfaha, Samuel; Kim, Moo-Kyung; Schreiber, Alan D.; Befus, A. Dean

    2006-01-01

    We have recently found that Syk is widely expressed in lung epithelial cells (EC) and participates in β1 integrin signaling. In this study, we assessed the role of Syk in regulation of NO production. Stimulation of human bronchial EC line HS-24 by TNF caused an increased expression of inducible nitric oxide synthase (iNOS). Inhibition of Syk using siRNA or piceatannol down-regulated the iNOS expression and reduced NO production. This effect occurred in EC simultaneously stimulated via β1 integrins, suggesting that TNF and β1 integrins provide co-stimulatory signals. Inhibition of Syk down-regulated TNF-induced p38 and p44/42 MAPK phosphorylation and nuclear translocation of p65 NF-κB. Thus, TNF-induced activation of pro-inflammatory signaling in EC leading to enhanced expression of iNOS and NO production was dependent on Syk. Syk-mediated signaling regulates NO production at least partly via activating the MAPK cascade. Understanding the role of Syk in airway EC may help in developing new therapeutic tools for inflammatory lung disorders

  13. Protein tyrosine kinases p53/56lyn and p72syk in MHC class I-mediated signal transduction in B lymphoma cells

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Bregenholt, S; Skov, S

    1998-01-01

    syk are among the tyrosine-phosphorylated proteins. The kinetics of phosphorylation of these kinases after MHC-I crosslinking differ from the kinetics observed after crosslinking of the B cell antigen receptor (BCR). Additional experiments were performed with chicken lyn- and syk-negative DT40 B cells...... mobilization of intracellular free calcium compared with MHC-I crosslinking of wild-type DT40 cells. Thus, expression of BCR at the cell surface is likely to be important for the signal cascade initiated by MHC-I crosslinking. Our data suggest that signal transduction initiated through ligation of the MHC...

  14. Aspergillus fumigatus stimulates the NLRP3 inflammasome through a pathway requiring ROS production and the Syk tyrosine kinase.

    Directory of Open Access Journals (Sweden)

    Najwane Saïd-Sadier

    Full Text Available Invasive aspergillosis (IA is a life-threatening disease that occurs in immunodepressed patients when infected with Aspergillus fumigatus. This fungus is the second most-common causative agent of fungal disease after Candida albicans. Nevertheless, much remains to be learned about the mechanisms by which A. fulmigatus activates the innate immune system. We investigated the inflammatory response to conidia and hyphae of A. fumigatus and specifically, their capacity to trigger activation of an inflammasome. Our results show that in contrast to conidia, hyphal fragments induce NLRP3 inflammasome assembly, caspase-1 activation and IL-1beta release from a human monocyte cell line. The ability of Aspergillus hyphae to activate the NLRP3 inflammasome in the monocytes requires K(+ efflux and ROS production. In addition, our data show that NLRP3 inflammasome activation as well as pro-IL-1beta expression relies on the Syk tyrosine kinase, which is downstream from the pathogen recognition receptor Dectin-1, reinforcing the importance of Dectin-1 in the innate immune response against fungal infection. Furthermore, we show that treatment of monocytes with corticosteroids inhibits transcription of the gene encoding IL-1beta. Thus, our data demonstrate that the innate immune response against A. fumigatus infection involves a two step activation process, with a first signal promoting expression and synthesis of pro-IL-1beta; and a second signal, involving Syk-induced activation of the NLRP3 inflammasome and caspase-1, allowing processing and secretion of the mature cytokine.

  15. Protein tyrosine kinases p53/56lyn and p72syk in MHC class I-mediated signal transduction in B lymphoma cells

    DEFF Research Database (Denmark)

    Pedersen, Anders Elm; Bregenholt, S; Skov, S

    1998-01-01

    Crosslinking of major histocompatibility complex class I (MHC-I) molecules on the surface of human B lymphoma cells was shown to induce protein tyrosine phosphorylation and mobilization of intracellular free calcium. Immunoprecipitations indicated that the protein tyrosine kinases p53/56lyn and p72......syk are among the tyrosine-phosphorylated proteins. The kinetics of phosphorylation of these kinases after MHC-I crosslinking differ from the kinetics observed after crosslinking of the B cell antigen receptor (BCR). Additional experiments were performed with chicken lyn- and syk-negative DT40 B cells...... and the results indicate that these two kinases have different substrate specificity and regulate intracellular free calcium differently in response to MHC-I crosslinking. In addition MHC-I crosslinking of a sIgM-negative DT40 chicken B cell variant results in less activity of tyrosine kinases and less...

  16. TEC family kinases in health and disease--loss-of-function of BTK and ITK and the gain-of-function fusions ITK-SYK and BTK-SYK.

    Science.gov (United States)

    Hussain, Alamdar; Yu, Liang; Faryal, Rani; Mohammad, Dara K; Mohamed, Abdalla J; Smith, C I Edvard

    2011-06-01

    The TEC family is ancient and constitutes the second largest family of cytoplasmic tyrosine kinases. In 1993, loss-of-function mutations in the BTK gene were reported as the cause of X-linked agammaglobulinemia. Of all the existing 90 tyrosine kinases in humans, Bruton's tyrosine kinase (BTK) is the kinase for which most mutations have been identified. These experiments of nature collectively provide a form of mutation scanning with direct implications for the several hundred endogenous signaling proteins carrying domains also found in BTK. In 2009, an inactivating mutation in the ITK gene was shown to cause susceptibility to lethal Epstein-Barr virus infection. Both kinases represent interesting targets for inhibition: in the case of BTK, as an immunosuppressant, whereas there is evidence that the inhibition of inducible T-cell kinase (ITK) could influence the infectivity of HIV and also have anti-inflammatory activity. Since 2006, several patients carrying a fusion protein, originating from a translocation joining genes encoding the kinases ITK and spleen tyrosine kinase (SYK), have been shown to develop T-cell lymphoma. We review these disease processes and also describe the role of the N-terminal pleckstrin homology-Tec homology (PH-TH) domain doublet of BTK and ITK in the downstream intracellular signaling of such fusion proteins. © 2011 The Authors Journal compilation © 2011 FEBS.

  17. Malassezia yeasts activate the NLRP3 inflammasome in antigen-presenting cells via Syk-kinase signalling.

    Science.gov (United States)

    Kistowska, Magdalena; Fenini, Gabriele; Jankovic, Dragana; Feldmeyer, Laurence; Kerl, Katrin; Bosshard, Philipp; Contassot, Emmanuel; French, Lars E

    2014-12-01

    Although being a normal part of the skin flora, yeasts of the genus Malassezia are associated with several common dermatologic conditions including pityriasis versicolour, seborrhoeic dermatitis (SD), folliculitis, atopic eczema/dermatitis (AE/AD) and dandruff. While Malassezia spp. are aetiological agents of pityriasis versicolour, a causal role of Malassezia spp. in AE/AD and SD remains to be established. Previous reports have shown that fungi such as Candida albicans and Aspergillus fumigatus are able to efficiently activate the NLRP3 inflammasome leading to robust secretion of the pro-inflammatory cytokine IL-1β. To date, innate immune responses to Malassezia spp. are not well characterized. Here, we show that different Malassezia species could induce NLRP3 inflammasome activation and subsequent IL-1β secretion in human antigen-presenting cells. In contrast, keratinocytes were not able to secrete IL-1β when exposed to Malassezia spp. Moreover, we demonstrate that IL-1β secretion in antigen-presenting cells was dependent on Syk-kinase signalling. Our results identify Malassezia spp. as potential strong inducers of pro-inflammatory responses when taken up by antigen-presenting cells and identify C-type lectin receptors and the NLRP3 inflammasome as crucial actors in this process. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Giant hub Src and Syk tyrosine kinase thermodynamic profiles recapitulate evolution

    Science.gov (United States)

    Phillips, J. C.

    2017-10-01

    Thermodynamic scaling theory, previously applied mainly to small proteins, here analyzes quantitative evolution of the titled functional network giant hub enzymes. The broad domain structure identified homologically is confirmed hydropathically using amino acid sequences only. The most surprising results concern the evolution of the tyrosine kinase globular surface roughness from avians to mammals, which is first order, compared to the evolution within mammals from rodents to humans, which is second order. The mystery of the unique amide terminal region of proto oncogene tyrosine protein kinase is resolved by the discovery there of a rare hydroneutral septad targeting cluster, which is paralleled by an equally rare octad catalytic cluster in tyrosine kinase in humans and a few other species (cat and dog). These results, which go far towards explaining why these proteins are among the largest giant hubs in protein interaction networks, use no adjustable parameters.

  19. Simultaneous inhibition of JAK and SYK kinases ameliorates chronic and destructive arthritis in mice

    NARCIS (Netherlands)

    Llop-Guevara, A.; Porras, M.; Cendon, C.; Ceglie, I. Di; Siracusa, F.; Madarena, F.; Rinotas, V.; Gomez, L.; Lent, P.L.E.M. van; Douni, E.; Chang, H.D.; Kamradt, T.; Roman, J.

    2015-01-01

    INTRODUCTION: Despite the broad spectrum of antirheumatic drugs, RA is still not well controlled in up to 30-50 % of patients. Inhibition of JAK kinases by means of the pan-JAK inhibitor tofacitinib has demonstrated to be effective even in difficult-to-treat patients. Here, we discuss whether the

  20. Sesquiterpene dimmer (DSF-27) inhibits the release of neuroinflammatory mediators from microglia by targeting spleen tyrosine kinase (Syk) and Janus kinase 2 (Jak2): Two major non-receptor tyrosine signaling proteins involved in inflammatory events

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Ke-Wu [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191 (China); Wang, Shu [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191 (China); Department of Medicinal Chemistry and Pharmaceutical Analysis, Logistics College of Chinese People' s Armed Police Forces, Tianjin 300162 (China); Dong, Xin; Jiang, Yong; Jin, Hong-Wei [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191 (China); Tu, Peng-Fei, E-mail: pengfeitu@vip.163.com [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191 (China)

    2014-03-15

    Non-receptor protein tyrosine kinases (NRPTKs)-dependent inflammatory signal transduction cascades play key roles in immunoregulation. However, drug intervention through NRPTKs-involved immunoregulation mechanism in microglia (the major immune cells of the central nervous system) has not been widely investigated. A main aim of the present study is to elucidate the contribution of two major NRPTKs (Syk and Jak2) in neuroinflammation suppression by a bioactive sesquiterpene dimmer (DSF-27). We found that LPS-stimulated BV-2 cells activated Syk and further initiated Akt/NF-κB inflammatory pathway. This Syk-dependent Akt/NF-κB inflammatory pathway can be effectively ameliorated by DSF-27. Moreover, Jak2 was activated by LPS, which was followed by transcriptional factor Stat3 activation. The Jak2/Stat3 signal was suppressed by DSF-27 through inhibition of Jak2 and Stat3 phosphorylation, promotion of Jak/Stat3 inhibitory factors PIAS3 expression, and down-regulation of ERK and p38 MAPK phosphorylation. Furthermore, DSF-27 protected cortical and mesencephalic dopaminergic neurons against neuroinflammatory injury. Taken together, our findings indicate NRPTK signaling pathways including Syk/NF-κB and Jak2/Stat3 cascades are potential anti-neuroinflammatory targets in microglia, and may also set the basis for the use of sesquiterpene dimmer as a therapeutic approach for neuroinflammation via interruption of these pathways. - Highlights: • Sesquiterpene dimmer DSF-27 inhibits inflammatory mediators' production in microglia. • Syk-dependent Akt/NF-κB pathway is important for DSF-27's anti-inflammation activity. • Jak2/Stat3 pathway is important for DSF-27's anti-inflammation activity. • Jak2/Stat3 signaling pathway is partly regulated by ERK and p38 MAPKs and PIAS3. • DSF-27 protects neurons against microglia-mediated neuroinflammatory injury.

  1. Sesquiterpene dimmer (DSF-27) inhibits the release of neuroinflammatory mediators from microglia by targeting spleen tyrosine kinase (Syk) and Janus kinase 2 (Jak2): Two major non-receptor tyrosine signaling proteins involved in inflammatory events

    International Nuclear Information System (INIS)

    Zeng, Ke-Wu; Wang, Shu; Dong, Xin; Jiang, Yong; Jin, Hong-Wei; Tu, Peng-Fei

    2014-01-01

    Non-receptor protein tyrosine kinases (NRPTKs)-dependent inflammatory signal transduction cascades play key roles in immunoregulation. However, drug intervention through NRPTKs-involved immunoregulation mechanism in microglia (the major immune cells of the central nervous system) has not been widely investigated. A main aim of the present study is to elucidate the contribution of two major NRPTKs (Syk and Jak2) in neuroinflammation suppression by a bioactive sesquiterpene dimmer (DSF-27). We found that LPS-stimulated BV-2 cells activated Syk and further initiated Akt/NF-κB inflammatory pathway. This Syk-dependent Akt/NF-κB inflammatory pathway can be effectively ameliorated by DSF-27. Moreover, Jak2 was activated by LPS, which was followed by transcriptional factor Stat3 activation. The Jak2/Stat3 signal was suppressed by DSF-27 through inhibition of Jak2 and Stat3 phosphorylation, promotion of Jak/Stat3 inhibitory factors PIAS3 expression, and down-regulation of ERK and p38 MAPK phosphorylation. Furthermore, DSF-27 protected cortical and mesencephalic dopaminergic neurons against neuroinflammatory injury. Taken together, our findings indicate NRPTK signaling pathways including Syk/NF-κB and Jak2/Stat3 cascades are potential anti-neuroinflammatory targets in microglia, and may also set the basis for the use of sesquiterpene dimmer as a therapeutic approach for neuroinflammation via interruption of these pathways. - Highlights: • Sesquiterpene dimmer DSF-27 inhibits inflammatory mediators' production in microglia. • Syk-dependent Akt/NF-κB pathway is important for DSF-27's anti-inflammation activity. • Jak2/Stat3 pathway is important for DSF-27's anti-inflammation activity. • Jak2/Stat3 signaling pathway is partly regulated by ERK and p38 MAPKs and PIAS3. • DSF-27 protects neurons against microglia-mediated neuroinflammatory injury

  2. SYK regulates mTOR signaling in AML.

    Science.gov (United States)

    Carnevale, J; Ross, L; Puissant, A; Banerji, V; Stone, R M; DeAngelo, D J; Ross, K N; Stegmaier, K

    2013-11-01

    Spleen tyrosine kinase (SYK) was recently identified as a new target in acute myeloid leukemia (AML); however, its mechanistic role in this disease is poorly understood. Based on the known interaction between SYK and mammalian target of rapamycin (mTOR) signaling in lymphoma, we hypothesized that SYK may regulate mTOR signaling in AML. Both small-molecule inhibition of SYK and SYK-directed shRNA suppressed mTOR and its downstream signaling effectors, as well as its upstream activator, AKT. Moreover, the inhibition of multiple nodes of the phosphatidylinositol 3'-kinase (PI3K) signaling pathway enhanced the effects of SYK suppression on AML cell viability and differentiation. Evaluation of the collateral mitogen-activated protein kinase (MAPK) pathway revealed a heterogeneous response to SYK inhibition in AML with downregulation of MEK and extracellular signal-regulated kinase (ERK) phosphorylation in some AML cell lines but a paradoxical increase in MEK/ERK phosphorylation in RAS-mutated AML. These studies reveal SYK as a regulator of mTOR and MAPK signaling in AML and demonstrate that inhibition of PI3K pathway activity enhances the effects of SYK inhibition on AML cell viability and differentiation.

  3. Depletion of STAT5 blocks TEL–SYK-induced APMF-type leukemia with myelofibrosis and myelodysplasia in mice

    International Nuclear Information System (INIS)

    Sprissler, C; Belenki, D; Maurer, H; Aumann, K; Pfeifer, D; Klein, C; Müller, T A; Kissel, S; Hülsdünker, J; Alexandrovski, J; Brummer, T; Jumaa, H; Duyster, J; Dierks, C

    2014-01-01

    The spleen tyrosine kinase (SYK) was identified as an oncogenic driver in a broad spectrum of hematologic malignancies. The in vivo comparison of three SYK containing oncogenes, SYK wt , TEL–SYK and IL-2-inducible T-cell kinase (ITK)-SYK revealed a general myeloexpansion and the establishment of three different hematologic (pre)diseases. SYK wt enhanced the myeloid and T-cell compartment, without leukemia/lymphoma development. ITK–SYK caused lethal T-cell lymphomas and the cytoplasmic TEL–SYK fusion induced an acute panmyelosis with myelofibrosis-type acute myeloid leukemia (AML) with up to 50% immature megakaryoblasts infiltrating bone marrow, spleen and liver, additional MPN features (myelofibrosis and granulocyte expansion) and MDS stigmata with megakaryocytic and erythroid dysplasia. LKS cells were reduced and all subsets (LT/ST/MPP) showed reduced proliferation rates. SYK inhibitor treatment (R788) of diseased TEL–SYK mice reduced leukocytosis, spleen and liver infiltration, enhanced the hematocrit and prolonged survival time, but could not significantly reduce myelofibrosis. Stat5 was identified as a major downstream mediator of TEL–SYK in vitro as well as in vivo. Consequently, targeted deletion of Stat5 in vivo completely abrogated TEL–SYK-induced AML and myelofibrosis development, proving Stat5 as a major driver of SYK-induced transformation. Our experiments highlight the important role of SYK in AML and myelofibrosis and prove SYK and STAT5 inhibitors as potent treatment options for those diseases

  4. SYK is a critical regulator of FLT3 in acute myeloid leukemia.

    Science.gov (United States)

    Puissant, Alexandre; Fenouille, Nina; Alexe, Gabriela; Pikman, Yana; Bassil, Christopher F; Mehta, Swapnil; Du, Jinyan; Kazi, Julhash U; Luciano, Frédéric; Rönnstrand, Lars; Kung, Andrew L; Aster, Jon C; Galinsky, Ilene; Stone, Richard M; DeAngelo, Daniel J; Hemann, Michael T; Stegmaier, Kimberly

    2014-02-10

    Cooperative dependencies between mutant oncoproteins and wild-type proteins are critical in cancer pathogenesis and therapy resistance. Although spleen tyrosine kinase (SYK) has been implicated in hematologic malignancies, it is rarely mutated. We used kinase activity profiling to identify collaborators of SYK in acute myeloid leukemia (AML) and determined that FMS-like tyrosine kinase 3 (FLT3) is transactivated by SYK via direct binding. Highly activated SYK is predominantly found in FLT3-ITD positive AML and cooperates with FLT3-ITD to activate MYC transcriptional programs. FLT3-ITD AML cells are more vulnerable to SYK suppression than FLT3 wild-type counterparts. In a FLT3-ITD in vivo model, SYK is indispensable for myeloproliferative disease (MPD) development, and SYK overexpression promotes overt transformation to AML and resistance to FLT3-ITD-targeted therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. 4-Chlorotetrazolo[1,5-a]quinoxaline inhibits activation of Syk kinase to suppress mast cells in vitro and mast cell-mediated passive cutaneous anaphylaxis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kui Lea [Center for Drug Development Assistance, National Institute of Food Drug Safety Evaluation (NIFDS), KFDA, Cheongwon-gun (Korea, Republic of); Ko, Na Young; Lee, Jun Ho; Kim, Do Kyun; Kim, Hyuk Soon; Kim, A-Ram; Her, Erk; Kim, Bokyung [Department of Immunology and physiology, College of Medicine, Konkuk University, Chungju (Korea, Republic of); Kim, Hyung Sik [College of Pharmacy, Pusan National University, Busan (Korea, Republic of); Moon, Eun-Yi [Department of Bioscience and Biotechnology, College of Biological Science, Sejong University, Seoul (Korea, Republic of); Kim, Young Mi [College of Pharmacy, Duksung Women' s University, Seoul (Korea, Republic of); Kim, Hang-Rae, E-mail: hangrae2@snu.ac.kr [Department of Anatomy, Seoul National University College of Medicine, Seoul (Korea, Republic of); Choi, Wahn Soo, E-mail: wahnchoi@kku.ac.kr [Department of Immunology and physiology, College of Medicine, Konkuk University, Chungju (Korea, Republic of)

    2011-12-15

    4-Chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. We aimed to study the effects of 4-chlorotetrazolo[1,5-a]quinoxaline on activation of mast cells in vitro and in mice. 4-Chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited degranulation of mast cells in a dose-dependent manner, and also suppressed the expression and secretion of TNF-{alpha} and IL-4 in mast cells. Mechanistically, 4-chlorotetrazolo[1,5-a]quinoxaline inhibited activating phosphorylation of Syk and LAT, which are crucial for early Fc{epsilon}RI-mediated signaling events, as well as Akt and MAP kinases, which play essential roles in the production of various pro-inflammatory cytokines in mast cells. Notably, although 4-chlorotetrazolo[1,5-a]quinoxaline inhibited the activation of Fyn and Syk, minimal inhibition was observed in mast cells in the case of Lyn. Furthermore, consistent with its in vitro activity, 4-chlorotetrazolo[1,5-a]quinoxaline significantly suppressed mast cell-mediated passive cutaneous anaphylaxis in mice. In summary, the results from this study demonstrate that 4-chlorotetrazolo[1,5-a]quinoxaline shows an inhibitory effect on mast cells in vitro and in vivo, and that this is mediated by inhibiting the activation of Syk in mast cells. Therefore, 4-chlorotetrazolo[1,5-a]quinoxaline could be useful in the treatment of mast cell-mediated allergic diseases. -- Highlights: Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. Black-Right-Pointing-Pointer The effect of 4-chlorotetrazolo[1,5-a]quinoxaline on mast cells was investigated. Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited Syk activation. Black-Right-Pointing-Pointer 4-chlorotetrazolo[1,5-a]quinoxaline could be useful for IgE-mediated allergy.

  6. 4-Chlorotetrazolo[1,5-a]quinoxaline inhibits activation of Syk kinase to suppress mast cells in vitro and mast cell-mediated passive cutaneous anaphylaxis in mice

    International Nuclear Information System (INIS)

    Park, Kui Lea; Ko, Na Young; Lee, Jun Ho; Kim, Do Kyun; Kim, Hyuk Soon; Kim, A-Ram; Her, Erk; Kim, Bokyung; Kim, Hyung Sik; Moon, Eun-Yi; Kim, Young Mi; Kim, Hang-Rae; Choi, Wahn Soo

    2011-01-01

    4-Chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. We aimed to study the effects of 4-chlorotetrazolo[1,5-a]quinoxaline on activation of mast cells in vitro and in mice. 4-Chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited degranulation of mast cells in a dose-dependent manner, and also suppressed the expression and secretion of TNF-α and IL-4 in mast cells. Mechanistically, 4-chlorotetrazolo[1,5-a]quinoxaline inhibited activating phosphorylation of Syk and LAT, which are crucial for early FcεRI-mediated signaling events, as well as Akt and MAP kinases, which play essential roles in the production of various pro-inflammatory cytokines in mast cells. Notably, although 4-chlorotetrazolo[1,5-a]quinoxaline inhibited the activation of Fyn and Syk, minimal inhibition was observed in mast cells in the case of Lyn. Furthermore, consistent with its in vitro activity, 4-chlorotetrazolo[1,5-a]quinoxaline significantly suppressed mast cell-mediated passive cutaneous anaphylaxis in mice. In summary, the results from this study demonstrate that 4-chlorotetrazolo[1,5-a]quinoxaline shows an inhibitory effect on mast cells in vitro and in vivo, and that this is mediated by inhibiting the activation of Syk in mast cells. Therefore, 4-chlorotetrazolo[1,5-a]quinoxaline could be useful in the treatment of mast cell-mediated allergic diseases. -- Highlights: ► 4-chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. ► The effect of 4-chlorotetrazolo[1,5-a]quinoxaline on mast cells was investigated. ► 4-chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited Syk activation. ► 4-chlorotetrazolo[1,5-a]quinoxaline could be useful for IgE-mediated allergy.

  7. The Syk protein tyrosine kinase can function independently of CD45 or Lck in T cell antigen receptor signaling

    NARCIS (Netherlands)

    Chu, D. H.; Spits, H.; Peyron, J. F.; Rowley, R. B.; Bolen, J. B.; Weiss, A.

    1996-01-01

    The protein tyrosine phosphatase CD45 is a critical component of the T cell antigen receptor (TCR) signaling pathway, acting as a positive regulator of Src family protein tyrosine kinases (PTKs) such as Lck. Most CD45-deficient human and murine T cell lines are unable to signal through their TCRs.

  8. A Combined Experimental and Computational Study of Vam3, a Derivative of Resveratrol, and Syk Interaction

    Directory of Open Access Journals (Sweden)

    Ming Jiang

    2014-09-01

    Full Text Available Spleen tyrosine kinase (Syk plays an indispensable role through preliminary extracellular antigen-induced crosslinking of Fc receptor (FcR in the pathogenesis of autoimmune disorders, such as rheumatoid arthritis. In this study, we identify Vam3, a dimeric derivative of resveratrol isolated from grapes, as an ATP-competitive inhibitor of Syk with an IC50 of 62.95 nM in an in vitro kinase assay. Moreover, docking and molecular dynamics simulation approaches were performed to get more detailed information about the binding mode of Vam3 and Syk. The results show that 11b-OH on ring-C and 4b-OH on ring-D could form two hydrogen bonds with Glu449 and Phe382 of Syk, respectively. In addition, arene-cation interaction between ring-D of Vam3 and Lys402 of Syk was also observed. These results indicate that ring-C and D play an essential role in Vam3–Syk interaction. Our studies may be helpful in the structural optimization of Vam3, and also aid the design of novel Syk inhibitors in the future.

  9. Reconstruction and signal propagation analysis of the Syk signaling network in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Aurélien Naldi

    2017-03-01

    Full Text Available The ability to build in-depth cell signaling networks from vast experimental data is a key objective of computational biology. The spleen tyrosine kinase (Syk protein, a well-characterized key player in immune cell signaling, was surprisingly first shown by our group to exhibit an onco-suppressive function in mammary epithelial cells and corroborated by many other studies, but the molecular mechanisms of this function remain largely unsolved. Based on existing proteomic data, we report here the generation of an interaction-based network of signaling pathways controlled by Syk in breast cancer cells. Pathway enrichment of the Syk targets previously identified by quantitative phospho-proteomics indicated that Syk is engaged in cell adhesion, motility, growth and death. Using the components and interactions of these pathways, we bootstrapped the reconstruction of a comprehensive network covering Syk signaling in breast cancer cells. To generate in silico hypotheses on Syk signaling propagation, we developed a method allowing to rank paths between Syk and its targets. We first annotated the network according to experimental datasets. We then combined shortest path computation with random walk processes to estimate the importance of individual interactions and selected biologically relevant pathways in the network. Molecular and cell biology experiments allowed to distinguish candidate mechanisms that underlie the impact of Syk on the regulation of cortactin and ezrin, both involved in actin-mediated cell adhesion and motility. The Syk network was further completed with the results of our biological validation experiments. The resulting Syk signaling sub-networks can be explored via an online visualization platform.

  10. Syk is indispensable for CpG-induced activation and differentiation of human B cells.

    Science.gov (United States)

    Kremlitzka, Mariann; Mácsik-Valent, Bernadett; Erdei, Anna

    2015-06-01

    B cells are efficiently activated by CpG oligodeoxynucleotides (ODNs) to produce pro-inflammatory cytokines and antibody (Ab). Here, we describe a so far unidentified, spleen tyrosine kinase (Syk)-dependent pathway, which is indispensable for CpG-induced human B cell activation. We show that triggering of B cells by CpG results in Syk and src kinase phosphorylation, proliferation, as well as cytokine and Ab production independent of the BCR. Notably, all these functions are abrogated when Syk is inhibited. We demonstrate that CpG-induced Syk activation originates from the cell surface in a TLR9-dependent manner. While inhibition of Syk does not influence the uptake of CpG ODNs, activation of the kinase is a prerequisite for the delivery of CpG into TLR9-containing endolysosomes and for the CpG-induced up-regulation of TLR9 expression. Our results reveal an alternative, Syk-dependent pathway of CpG-induced B cell stimulation, which is initiated at the plasma membrane and seems to be an upstream requirement for endosomal TLR9-driven B cell proliferation and differentiation.

  11. Discovery of new Syk inhibitors through structure-based virtual screening.

    Science.gov (United States)

    Huang, Yahui; Zhang, Youjun; Fan, Kexin; Dong, Guoqiang; Li, Bohua; Zhang, Wannian; Li, Jian; Sheng, Chunquan

    2017-04-15

    Spleen tyrosine kinase (Syk) is an attractive target for the discovery of new treatments for inflammatory and autoimmune disorders. Structure-based virtual screening was performed for identifying novel scaffolds of Syk inhibitors. A total of 16 hits were discovered in the enzyme assay and 8 compounds had an IC 50 value lower than 10μM. In particular, compound 11 (IC 50 =3.2μM) was active in the cellular Syk assay and could inhibit lymphocytes proliferation in a dose-dependent manner, which could be used as a good starting point for the discovery of new class of Syk inhibitors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A novel spleen tyrosine kinase inhibitor blocks c-Jun N-terminal kinase-mediated gene expression in synoviocytes

    NARCIS (Netherlands)

    Cha, Hoon-Suk; Boyle, David L.; Inoue, Tomoyuki; Schoot, Reineke; Tak, Paul P.; Pine, Polly; Firestein, Gary S.

    2006-01-01

    Spleen tyrosine kinase (Syk) is a key regulator of cell signaling induced by cytokines or Fc receptor engagement. However, the role of Syk in rheumatoid arthritis (RA) is not known yet. We investigated the pathways activated by Syk in tumor necrosis factor-alpha (TNFalpha)-stimulated fibroblast-like

  13. Syk-Mediated Suppression of Inflammatory Responses by Cordyceps bassiana.

    Science.gov (United States)

    Yang, Woo Seok; Nam, Gyeong Sug; Kim, Mi-Yeon; Cho, Jae Youl

    2017-01-01

    The fruit body of artificially cultivated Cordyceps bassiana has been reported to exhibit anti-inflammatory and anticancer activities. Although it has been suggested that the fruit body has neutraceutic and pharmaceutic biomaterial potential, the exact anti-inflammatory molecular mechanism has not been fully elucidated. In this study, we demonstrated the immunopharmacologic activity of Cordyceps bassiana under in vitro conditions and investigated its anti-inflammatory mechanism. Water extract (Cm-WE) of the fruit body of artificially cultivated Cordyceps bassiana without polysaccharide fractions reduced the expression of the proinflammatory genes cyclooxygenase (COX)-2, interleukin (IL)-12, and inducible nitric oxide synthase (iNOS) and promoted the expression of the anti-inflammatory gene IL-10 in lipopolysaccharide (LPS)-treated RAW264.7 cells. In addition, this fraction suppressed proliferation and interferon (IFN)-[Formula: see text] production in splenic T lymphocytes. Cm-WE blocked the activation of nuclear factor (NF)-[Formula: see text]B and activator protein (AP)-1 and their upstream inflammatory signaling cascades, including Syk, MEK, and JNK. Using kinase assays, Syk was identified as the target enzyme most strongly inhibited by Cm-WE. These results strongly suggest that Cm-WE suppresses inflammatory responses by inhibiting Syk kinase activity, with potential implications for novel neutraceutic and pharmaceutic biomaterials.

  14. Targeted downregulation of platelet CLEC-2 occurs through Syk-independent internalization

    OpenAIRE

    Lorenz, Viola; Stegner, David; Stritt, Simon; Vögtle, Timo; Kiefer, Friedemann; Witke, Walter; Schymeinsky, Jürgen; Watson, Steve P.; Walzog, Barbara; Nieswandt, Bernhard

    2015-01-01

    CLEC-2 can be downregulated from circulating platelets by anti–CLEC-2 antibodies through Src-family kinase-dependent internalization.Platelet-specific Syk deficiency abrogates anti–CLEC-2 antibodies-induced thrombocytopenia, but not CLEC-2 internalization.

  15. SYK expression level distinguishes control from BRCA1-mutated lymphocytes

    Directory of Open Access Journals (Sweden)

    Zahavi T

    2018-03-01

    Full Text Available Tamar Zahavi,1,2,* Amir Sonnenblick,1,3,* Yael Shimshon,2 Luna Kadouri,1 Tamar Peretz,1 Asher Y Salmon,1,* Mali Salmon-Divon,2,* 1Sharett Institute of Oncology, Hadassah Hebrew University Medical Center, Jerusalem, Israel; 2Genomic Bioinformatics Laboratory, Department of Molecular Biology, Ariel University, Ariel, Israel; 3Sackler Faculty of Medicine, Sourasky Medical Center, Institute of Oncology, Tel Aviv University, Tel Aviv, Israel *These authors contributed equally to this work Background: About 5%–10% of breast cancer and 10%–15% of ovarian cancer are hereditary. BRCA1 and BRCA2 are the most common germline mutations found in both inherited breast and ovarian cancers. Once these mutations are identified and classified, a course of action to reduce the risk of developing either ovarian or breast cancer – including surveillance and surgery – is carried out. Purpose: The purpose of the current research is to characterize the gene expression differences between healthy cells harboring a mutation in BRCA1/2 genes and normal cells. This will allow detection of candidate genes and help identify women who carry functional BRCA1/2 mutations, which cannot always be detected by the available sequencing methods, for example, carriers of mutations found in regulatory sequences of the genes. Materials and methods: Our cohort consisted of 50 healthy women, of whom 24 were individuals with BRCA1 or BRCA2 heterozygous mutations and 26 were non-carrier controls. RNA purified from non-irradiated lymphocytes of nine BRCA1/2 mutation carriers versus four control mutation-negative individuals was utilized for RNA-Seq analysis. The selected RNA-Seq transcripts were validated, and the levels of spleen tyrosine kinase (SYK mRNA were measured by using real-time quantitative polymerase chain reaction. Results: Differences in gene expression were found when comparing untreated lymphocytes of BRCA1/2 mutation carriers and controls. Among others, the SYK gene

  16. BCL6 modulates tonic BCR signaling in diffuse large B-cell lymphomas by repressing the SYK phosphatase, PTPROt.

    Science.gov (United States)

    Juszczynski, Przemyslaw; Chen, Linfeng; O'Donnell, Evan; Polo, Jose M; Ranuncolo, Stella M; Dalla-Favera, Riccardo; Melnick, Ari; Shipp, Margaret A

    2009-12-17

    Tonic B-cell receptor (BCR) signaling is a key survival pathway during normal B-cell ontogenesis and in a subset of diffuse large B-cell lymphomas (DLBCLs). We previously demonstrated that BCR-dependent DLBCL cell lines and primary tumors underwent apoptosis after treatment with an ATP-competitive inhibitor of the BCR-associated spleen tyrosine kinase (SYK). These "BCR-type" tumors also have more abundant expression of the transcriptional repressor, BCL6, and increased sensitivity to BCL6 inhibition. Herein, we evaluated potential connections between BCL6-mediated transcriptional repression and SYK-dependent BCR signaling. In transcriptionally profiled normal B-cell subsets (naive, germinal center, and memory B cells) and in primary DLBCLs, there were reciprocal patterns of expression of BCL6 and the SYK tyrosine phosphatase PTPROt. BCL6 repressed PTPROt transcription via a direct interaction with functional BCL6 binding sites in the PTPROt promoter. Enforced expression of BCL6 in normal naive B cells and RNAi-mediated depletion of BCL6 in germinal center B cells directly modulated PTPROt expression. In "BCR-type" DLBCLs, BCL6 depletion increased PTPROt expression and decreased phosphorylation of SYK and the downstream adaptor protein BLNK. Because BCL6 augments BCR signaling and BCL6 and SYK are both promising therapeutic targets in many DLBCLs, combined inhibition of these functionally related pathways warrants further study.

  17. SYK inhibition thwarts the BAFF - B-cell receptor crosstalk and thereby antagonizes Mcl-1 in chronic lymphocytic leukemia.

    Science.gov (United States)

    Paiva, Cody; Rowland, Taylor A; Sreekantham, Bhargava; Godbersen, Claire; Best, Scott R; Kaur, Prabhjot; Loriaux, Marc M; Spurgeon, Stephen E F; Danilova, Olga V; Danilov, Alexey V

    2017-11-01

    Although small molecule inhibitors of B-cell receptor-associated kinases have revolutionized therapy in chronic lymphocytic leukemia (CLL), responses are incomplete. Pro-survival signaling emanating from the microenvironment may foster therapeutic resistance of the malignant B cells resident in the protective lymphoid niches. B-cell activating factor (BAFF) is critical to the survival of both healthy and neoplastic B cells. However, the pro-survival pathways triggered by BAFF have not been fully characterized. Here we show that BAFF elicited resistance to spontaneous and drug-induced apoptosis in stromal co-cultures, induced activation of both canonical and non-canonical NFκB signaling pathways, and triggered B-cell receptor signaling in CLL cells, independently of IGHV mutational status. SYK, a proximal kinase in the B-cell receptor signaling cascade, acted via STAT3 to bolster transcription of the anti-apoptotic protein Mcl-1, thereby contributing to apoptosis resistance in BAFF-stimulated cells. SYK inhibitor entospletinib downregulated Mcl-1, abrogating BAFF-mediated cell survival. BAFF-B-cell receptor crosstalk in neoplastic B cells was mediated by SYK interaction with TRAF2/TRAF3 complex. Thus, SYK inhibition is a promising therapeutic strategy uniquely poised to antagonize crosstalk between BAFF and B-cell receptor, thereby disrupting the pro-survival microenvironment signaling in chronic lymphocytic leukemia. Copyright© Ferrata Storti Foundation.

  18. Syk signaling in dendritic cells orchestrates innate resistance to systemic fungal infection.

    Directory of Open Access Journals (Sweden)

    Paul G Whitney

    2014-07-01

    Full Text Available Host protection from fungal infection is thought to ensue in part from the activity of Syk-coupled C-type lectin receptors and MyD88-coupled toll-like receptors in myeloid cells, including neutrophils, macrophages and dendritic cells (DCs. Given the multitude of cell types and receptors involved, elimination of a single pathway for fungal recognition in a cell type such as DCs, primarily known for their ability to prime T cell responses, would be expected to have little effect on innate resistance to fungal infection. Here we report that this is surprisingly not the case and that selective loss of Syk but not MyD88 in DCs abrogates innate resistance to acute systemic Candida albicans infection in mice. We show that Syk expression by DCs is necessary for IL-23p19 production in response to C. albicans, which is essential to transiently induce GM-CSF secretion by NK cells that are recruited to the site of fungal replication. NK cell-derived-GM-CSF in turn sustains the anti-microbial activity of neutrophils, the main fungicidal effectors. Thus, the activity of a single kinase in a single myeloid cell type orchestrates a complex series of molecular and cellular events that underlies innate resistance to fungal sepsis.

  19. Inhibition of Syk with fostamatinib disodium has significant clinical activity in non-Hodgkin lymphoma and chronic lymphocytic leukemia.

    Science.gov (United States)

    Friedberg, Jonathan W; Sharman, Jeff; Sweetenham, John; Johnston, Patrick B; Vose, Julie M; Lacasce, Ann; Schaefer-Cutillo, Julia; De Vos, Sven; Sinha, Rajni; Leonard, John P; Cripe, Larry D; Gregory, Stephanie A; Sterba, Michael P; Lowe, Ann M; Levy, Ronald; Shipp, Margaret A

    2010-04-01

    Certain malignant B cells rely on B-cell receptor (BCR)-mediated survival signals. Spleen tyrosine kinase (Syk) initiates and amplifies the BCR signal. In in vivo analyses of B-cell lymphoma cell lines and primary tumors, Syk inhibition induces apoptosis. These data prompted a phase 1/2 clinical trial of fostamatinib disodium, the first clinically available oral Syk inhibitor, in patients with recurrent B-cell non-Hodgkin lymphoma (B-NHL). Dose-limiting toxicity in the phase 1 portion was neutropenia, diarrhea, and thrombocytopenia, and 200 mg twice daily was chosen for phase 2 testing. Sixty-eight patients with recurrent B-NHL were then enrolled in 3 cohorts: (1) diffuse large B-cell lymphoma (DLBCL), (2) follicular lymphoma (FL), and (3) other NHL, including mantle cell lymphoma (MCL), marginal zone lymphoma (MZL), mucosa-associated lymphoid tissue lymphoma, lymphoplasmacytic lymphomas, and small lymphocytic leukemia/chronic lymphocytic leukemia (SLL/CLL). Common toxicities included diarrhea, fatigue, cytopenias, hypertension, and nausea. Objective response rates were 22% (5 of 23) for DLBCL, 10% (2 of 21) for FL, 55% (6 of 11) for SLL/CLL, and 11% (1/9) for MCL. Median progression-free survival was 4.2 months. Disrupting BCR-induced signaling by inhibiting Syk represents a novel and active therapeutic approach for NHL and SLL/CLL. This trial was registered at www.clinicaltrials.gov as #NCT00446095.

  20. Syk and IRAK1 Contribute to Immunopharmacological Activities of Anthraquinone-2-carboxlic Acid

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    Jae Gwang Park

    2016-06-01

    Full Text Available Anthraquinone-2-carboxlic acid (9,10-dihydro-9,10-dioxo-2-anthracenecarboxylic acid, AQCA was identified as one of the major anthraquinones in Brazilian taheebo. Since there was no report explaining its immunopharmacological actions, in this study, we aimed to investigate the molecular mechanism of AQCA-mediated anti-inflammatory activity using reporter gene assays, kinase assays, immunoblot analyses, and overexpression strategies with lipopolysaccharide (LPS-treated macrophages. AQCA was found to suppress the release of nitric oxide (NO and prostaglandin (PG E2 from LPS-treated peritoneal macrophages without displaying any toxic side effects. Molecular analysis revealed that AQCA was able to inhibit the activation of the nuclear factor (NF-κB and activator protein (AP-1 pathways by direct suppression of upstream signaling enzymes including interleukin-1 receptor-associated kinase 1 (IRAK1 and spleen tyrosine kinase (Syk. Therefore, our data strongly suggest that AQCA-mediated suppression of inflammatory responses could be managed by a direct interference of signaling cascades including IRAK and Syk, linked to the activation of NF-κB and AP-1.

  1. Syk and IRAK1 Contribute to Immunopharmacological Activities of Anthraquinone-2-carboxlic Acid.

    Science.gov (United States)

    Park, Jae Gwang; Son, Young-Jin; Kim, Mi-Yeon; Cho, Jae Youl

    2016-06-22

    Anthraquinone-2-carboxlic acid (9,10-dihydro-9,10-dioxo-2-anthracenecarboxylic acid, AQCA) was identified as one of the major anthraquinones in Brazilian taheebo. Since there was no report explaining its immunopharmacological actions, in this study, we aimed to investigate the molecular mechanism of AQCA-mediated anti-inflammatory activity using reporter gene assays, kinase assays, immunoblot analyses, and overexpression strategies with lipopolysaccharide (LPS)-treated macrophages. AQCA was found to suppress the release of nitric oxide (NO) and prostaglandin (PG) E₂ from LPS-treated peritoneal macrophages without displaying any toxic side effects. Molecular analysis revealed that AQCA was able to inhibit the activation of the nuclear factor (NF)-κB and activator protein (AP)-1 pathways by direct suppression of upstream signaling enzymes including interleukin-1 receptor-associated kinase 1 (IRAK1) and spleen tyrosine kinase (Syk). Therefore, our data strongly suggest that AQCA-mediated suppression of inflammatory responses could be managed by a direct interference of signaling cascades including IRAK and Syk, linked to the activation of NF-κB and AP-1.

  2. Syk/Src Pathway-Targeted Inhibition of Skin Inflammatory Responses by Carnosic Acid

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    Jueun Oh

    2012-01-01

    Full Text Available Carnosic acid (CA is a diterpene compound exhibiting antioxidative, anticancer, anti-angiogenic, anti-inflammatory, anti-metabolic disorder, and hepatoprotective and neuroprotective activities. In this study, the effect of CA on various skin inflammatory responses and its inhibitory mechanism were examined. CA strongly suppressed the production of IL-6, IL-8, and MCP-1 from keratinocyte HaCaT cells stimulated with sodium lauryl sulfate (SLS and retinoic acid (RA. In addition, CA blocked the release of nitric oxide (NO, tumor necrosis factor (TNF-α, and prostaglandin E2 (PGE2 from RAW264.7 cells activated by the toll-like receptor (TLR-2 ligands, Gram-positive bacterium-derived peptidoglycan (PGN and pam3CSK, and the TLR4 ligand, Gram-negative bacterium-derived lipopolysaccharide (LPS. CA arrested the growth of dermatitis-inducing Gram-positive and Gram-negative microorganisms such Propionibacterium acnes, Pseudomonas aeruginosa, and Staphylococcus aureus. CA also blocked the nuclear translocation of nuclear factor (NF-κB and its upstream signaling including Syk/Src, phosphoinositide 3-kinase (PI3K, Akt, inhibitor of κBα (IκBα kinase (IKK, and IκBα for NF-κB activation. Kinase assays revealed that Syk could be direct enzymatic target of CA in its anti-inflammatory action. Therefore, our data strongly suggest the potential of CA as an anti-inflammatory drug against skin inflammatory responses with Src/NF-κB inhibitory properties.

  3. Autoimmune regulator (AIRE) contributes to Dectin-1-induced TNF-α production and complexes with caspase recruitment domain-containing protein 9 (CARD9), spleen tyrosine kinase (Syk), and Dectin-1.

    Science.gov (United States)

    Pedroza, Luis A; Kumar, Vipul; Sanborn, Keri B; Mace, Emily M; Niinikoski, Harri; Nadeau, Kari; Vasconcelos, Dewton de Moraes; Perez, Elena; Jyonouchi, Soma; Jyonouchi, Harumi; Banerjee, Pinaki P; Ruuskanen, Olli; Condino-Neto, Antonio; Orange, Jordan S

    2012-02-01

    Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome is a complex immunologic disease caused by mutation of the autoimmune regulator (AIRE) gene. Autoimmunity in patients with APECED syndrome has been shown to result from deficiency of AIRE function in transcriptional regulation of thymic peripheral tissue antigens, which leads to defective T-cell negative selection. Candidal susceptibility in patients with APECED syndrome is thought to result from aberrant adaptive immunity. To determine whether AIRE could function in anticandidal innate immune signaling, we investigated an extrathymic role for AIRE in the immune recognition of β-glucan through the Dectin-1 pathway, which is required for defense against Candida species. Innate immune signaling through the Dectin-1 pathway was assessed in both PBMCs from patients with APECED syndrome and a monocytic cell line. Subcellular localization of AIRE was assessed by using confocal microscopy. PBMCs from patients with APECED syndrome had reduced TNF-α responses after Dectin-1 ligation but in part used a Raf-1-mediated pathway to preserve function. In the THP-1 human monocytic cell line, reducing AIRE expression resulted in significantly decreased TNF-α release after Dectin-1 ligation. AIRE formed a transient complex with the known Dectin-1 pathway components phosphorylated spleen tyrosine kinase and caspase recruitment domain-containing protein 9 after receptor ligation and localized with Dectin-1 at the cell membrane. AIRE can participate in the Dectin-1 signaling pathway, indicating a novel extrathymic role for AIRE and a defect that likely contributes to fungal susceptibility in patients with APECED syndrome. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  4. SYK Inhibition Modulates Distinct PI3K/AKT-dependent Survival Pathways and Cholesterol Biosynthesis in Diffuse Large B-cell Lymphomas

    Science.gov (United States)

    Chen, Linfeng; Monti, Stefano; Juszczynski, Przemyslaw; Ouyang, Jing; Chapuy, Bjoern; Neuberg, Donna; Doench, John G.; Bogusz, Agata M.; Habermann, Thomas M.; Dogan, Ahmet; Witzig, Thomas E.; Kutok, Jeffery L.; Rodig, Scott J.; Golub, Todd; Shipp, Margaret A.

    2013-01-01

    SUMMARY B-cell receptor (BCR) signaling pathway components represent promising treatment targets in diffuse large B-cell lymphoma (DLBCL) and additional B-cell tumors. BCR signaling activates spleen tyrosine kinase (SYK) and downstream pathways including PI3K/AKT and NF-κB. In previous studies, chemical SYK blockade selectively decreased BCR signaling and induced apoptosis of BCR-dependent DLBCLs. Herein, we characterize distinct SYK/PI3K-dependent survival pathways in DLBCLs with high or low baseline NF-κB activity including selective repression of the pro-apoptotic HRK protein in NF-κB-low tumors. We also define SYK/PI3K-dependent cholesterol biosynthesis as a feed-forward mechanism of maintaining the integrity of BCRs in lipid rafts in DLBCLs with low or high NF-κB. In addition, SYK amplification and PTEN deletion are identified as selective genetic alterations in primary “BCR”-type DLBCLs. PMID:23764004

  5. SYK inhibition modulates distinct PI3K/AKT- dependent survival pathways and cholesterol biosynthesis in diffuse large B cell lymphomas.

    Science.gov (United States)

    Chen, Linfeng; Monti, Stefano; Juszczynski, Przemyslaw; Ouyang, Jing; Chapuy, Bjoern; Neuberg, Donna; Doench, John G; Bogusz, Agata M; Habermann, Thomas M; Dogan, Ahmet; Witzig, Thomas E; Kutok, Jeffery L; Rodig, Scott J; Golub, Todd; Shipp, Margaret A

    2013-06-10

    B cell receptor (BCR) signaling pathway components represent promising treatment targets in diffuse large B cell lymphoma (DLBCL) and additional B cell tumors. BCR signaling activates spleen tyrosine kinase (SYK) and downstream pathways including PI3K/AKT and NF-κB. In previous studies, chemical SYK blockade selectively decreased BCR signaling and induced apoptosis of BCR-dependent DLBCLs. Herein, we characterize distinct SYK/PI3K-dependent survival pathways in DLBCLs with high or low baseline NF-κB activity including selective repression of the pro-apoptotic HRK protein in NF-κB-low tumors. We also define SYK/PI3K-dependent cholesterol biosynthesis as a feed-forward mechanism of maintaining the integrity of BCRs in lipid rafts in DLBCLs with low or high NF-κB. In addition, SYK amplification and PTEN deletion are identified as selective genetic alterations in primary "BCR"-type DLBCLs. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. 1-(2,3-Dibenzimidazol-2-ylpropyl-2-methoxybenzene Is a Syk Inhibitor with Anti-Inflammatory Properties

    Directory of Open Access Journals (Sweden)

    Eunji Kim

    2016-04-01

    Full Text Available Inflammation is the protective action of our bodies against external pathogens by recognition of pathogen-associated molecular patterns (PAMPs via pattern recognition receptors (PRRs. Proper regulation of inflammatory responses is required to maintain our body’s homeostasis, as well as there are demands to develop proper acute or chronic inflammation. In this study, we elucidated the regulatory mechanism of NF-κB-mediated inflammatory responses by a novel compound, 1-(2,3-dibenzimidazol-2-ylpropyl-2-methoxybenzene (DBMB. We found that DBMB suppressed inflammatory mediators, nitric oxide (NO and prostaglandin E2 (PGE2, reacted to exposure to a number of toll like receptor (TLR ligands. Such observations occurred following to decreased mRNA expression of several pro-inflammatory mediators, and such diminished mRNA levels were caused by inhibited transcriptional factor nuclear factor (NF-κB, as evaluated by luciferase reporter assay and molecular biological approaches. To find the potential targets of DBMB, we screened phosphorylated forms of NF-κB signal molecules: inhibitor of κBα (IκBα, IκB kinase (IKKα/β, Akt, 3-phosphoinositide dependent protein kinase-1 (PDK1, p85, and spleen tyrosine kinase (Syk. We found that DBMB treatment could suppress signal transduction through these molecules. Additionally, we conducted in vitro kinase assays using immunoprecipitated Syk and its substrate, p85. Consequently, we could say that DBMB clearly suppressed the kinase activity of Syk kinase activity. Together, our results demonstrate that synthetic DBMB has an effect on the inflammatory NF-κB signaling pathway and suggest the potential for clinical use in the treatment of inflammatory diseases.

  7. Quantum ergodicity in the SYK model

    Science.gov (United States)

    Altland, Alexander; Bagrets, Dmitry

    2018-05-01

    We present a replica path integral approach describing the quantum chaotic dynamics of the SYK model at large time scales. The theory leads to the identification of non-ergodic collective modes which relax and eventually give way to an ergodic long time regime (describable by random matrix theory). These modes, which play a role conceptually similar to the diffusion modes of dirty metals, carry quantum numbers which we identify as the generators of the Clifford algebra: each of the 2N different products that can be formed from N Majorana operators defines one effective mode. The competition between a decay rate quickly growing in the order of the product and a density of modes exponentially growing in the same parameter explains the characteristics of the system's approach to the ergodic long time regime. We probe this dynamics through various spectral correlation functions and obtain favorable agreement with existing numerical data.

  8. 3D Picture of the SYK-VAV1 Protein Complex: Tracking the B-Cell Signal One Complex at a Time

    Directory of Open Access Journals (Sweden)

    Dan I. Piraner

    2011-01-01

    Full Text Available Protein signaling is the key method by which cells recognize a stimulus from their environment and convert it into a response. Signaling occurs in many forms: hormones, growth factors, and even proteins may act as signals from the environment. The response to their detection must be carried from the cell surface, where the signal is detected, to the nucleus, where the cell alters its DNA expression. This study analyzes one component in the signaling pathway of Spleen Tyrosine Kinase (Syk. The Syk protein receives a signal from B-cell receptors and amplifies it, resulting in an adaptive immune response and the production of antibodies for targeting foreign molecules. Strikingly, constant amplification of the Syk signal can transform B-cells into a cancerous phenotype and has been associated with cancers of the lymphatic system. Syk has also been implicated in autoimmune diseases such as rheumatoid arthritis. This study uses nuclear magnetic resonance spectroscopy to determine the structure of a segment from the Syk protein bound to Vav1, a downstream signaling protein that has been implicated in various cancers. The preliminary result will be refined using a molecular dynamics simulation to obtain the most energetically stable conformation of the protein-ligand interaction. The terminal results of this experiment will reveal the structural details of the Syk-Vav1 interaction, which may describe a possible therapeutic target in the treatment of proliferative B-cell disorders, as well as some types of cancer. Using this information, one or more drugs may be synthesized to block the interaction in cancerous cells, providing a therapeutic avenue to treat the disease.

  9. ZAP-70 and p72syk are signaling response elements through MHC class II molecules

    DEFF Research Database (Denmark)

    Kanner, S B; Grosmaire, L S; Blake, J

    1995-01-01

    Ligation of major histocompatibility complex (MHC) class II antigens expressed on antigen-activated human CD4+ T-lymphocytes induces early signal transduction events including the activation of tyrosine kinases, the tyrosine phosphorylation of phospholipase-C gamma 1 and the mobilization...... of intracellular calcium. Similar responses have been observed in B-cells following stimulation of MHC class II molecules, including the increased production of intracellular cAMP. In this report, we demonstrate that the ZAP-70 tyrosine kinase is a responsive signaling element following cross-linking of HLA...... by herbimycin A. MHC class II ligation on B-lymphocytes resulted in cell death, which was both qualitatively distinct from Fas-induced apoptosis and partially protected by herbimycin A pretreatment. Thus, ligation of MHC class II molecules expressed on human lymphocytes stimulates the ZAP-70/p72syk family...

  10. Spleen tyrosine kinase mediates high glucose-induced transforming growth factor-{beta}1 up-regulation in proximal tubular epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Won Seok; Chang, Jai Won [Division of Nephrology, Department of Internal Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Han, Nam Jeong [Department of Cell Biology, Asan Institute for Life Sciences, Seoul (Korea, Republic of); Lee, Sang Koo [Division of Nephrology, Department of Internal Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Park, Su-Kil, E-mail: skpark@amc.seoul.kr [Division of Nephrology, Department of Internal Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of)

    2012-09-10

    The role of spleen tyrosine kinase (Syk) in high glucose-induced intracellular signal transduction has yet to be elucidated. We investigated whether Syk is implicated in high glucose-induced transforming growth factor-{beta}1 (TGF-{beta}1) up-regulation in cultured human proximal tubular epithelial cells (HK-2 cell). High glucose increased TGF-{beta}1 gene expression through Syk, extracellular signal-regulated kinase (ERK), AP-1 and NF-{kappa}B. High glucose-induced AP-1 DNA binding activity was decreased by Syk inhibitors and U0126 (an ERK inhibitor). Syk inhibitors suppressed high glucose-induced ERK activation, whereas U0126 had no effect on Syk activation. High glucose-induced NF-{kappa}B DNA binding activity was also decreased by Syk inhibitors. High glucose increased nuclear translocation of p65 without serine phosphorylation of I{kappa}B{alpha} and without degradation of I{kappa}B{alpha}, but with an increase in tyrosine phosphorylation of I{kappa}B{alpha} that may account for the activation of NF-{kappa}B. Both Syk inhibitors and Syk-siRNA attenuated high glucose-induced I{kappa}B{alpha} tyrosine phosphorylation and p65 nuclear translocation. Depletion of p21-activated kinase 2 (Pak2) by transfection of Pak2-siRNA abolished high glucose-induced Syk activation. In summary, high glucose-induced TGF-{beta}1 gene transcription occurred through Pak2, Syk and subsequent ERK/AP-1 and NF-{kappa}B pathways. This suggests that Syk might be implicated in the diabetic kidney disease.

  11. DMPD: Complement-mediated phagocytosis--the role of Syk. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16754322 Complement-mediated phagocytosis--the role of Syk. Tohyama Y, Yamamura H. ...IUBMB Life. 2006 May-Jun;58(5-6):304-8. (.png) (.svg) (.html) (.csml) Show Complement-mediated phagocytosis-...-the role of Syk. PubmedID 16754322 Title Complement-mediated phagocytosis--the role of Syk. Authors Tohyama

  12. Targeted downregulation of platelet CLEC-2 occurs through Syk-independent internalization

    Science.gov (United States)

    Lorenz, Viola; Stegner, David; Stritt, Simon; Vögtle, Timo; Kiefer, Friedemann; Witke, Walter; Schymeinsky, Jürgen; Watson, Steve P.; Walzog, Barbara

    2015-01-01

    Platelet aggregation at sites of vascular injury is not only essential for hemostasis, but may also cause acute ischemic disease states such as myocardial infarction or stroke. The hemi-immunoreceptor tyrosine-based activation motif–containing C-type lectinlike receptor 2 (CLEC-2) mediates powerful platelet activation through a Src- and spleen tyrosine kinase (Syk)–dependent tyrosine phosphorylation cascade. Thereby, CLEC-2 not only contributes to thrombus formation and stabilization but also plays a central role in blood-lymphatic vessel development, tumor metastasis, and prevention of inflammatory bleeding, making it a potential pharmacologic target to modulate these processes. We have previously shown that injection of the anti–CLEC-2 antibody, INU1, results in virtually complete immunodepletion of platelet CLEC-2 in mice, which is, however, preceded by a severe transient thrombocytopenia thereby limiting its potential therapeutic use. The mechanisms underlying this targeted CLEC-2 downregulation have remained elusive. Here, we show that INU1-induced CLEC-2 immunodepletion occurs through Src-family kinase–dependent receptor internalization in vitro and in vivo, presumably followed by intracellular degradation. In mice with platelet-specific Syk deficiency, INU1-induced CLEC-2 internalization/degradation was fully preserved whereas the associated thrombocytopenia was largely prevented. These results show for the first time that CLEC-2 can be downregulated from the platelet surface through internalization in vitro and in vivo and that this can be mechanistically uncoupled from the associated antibody-induced thrombocytopenia. PMID:25795918

  13. Diffusion in higher dimensional SYK model with complex fermions

    Science.gov (United States)

    Cai, Wenhe; Ge, Xian-Hui; Yang, Guo-Hong

    2018-01-01

    We construct a new higher dimensional SYK model with complex fermions on bipartite lattices. As an extension of the original zero-dimensional SYK model, we focus on the one-dimension case, and similar Hamiltonian can be obtained in higher dimensions. This model has a conserved U(1) fermion number Q and a conjugate chemical potential μ. We evaluate the thermal and charge diffusion constants via large q expansion at low temperature limit. The results show that the diffusivity depends on the ratio of free Majorana fermions to Majorana fermions with SYK interactions. The transport properties and the butterfly velocity are accordingly calculated at low temperature. The specific heat and the thermal conductivity are proportional to the temperature. The electrical resistivity also has a linear temperature dependence term.

  14. The 2010 patent landscape for spleen tyrosine kinase inhibitors.

    Science.gov (United States)

    Moretto, Alessandro F; Dehnhardt, Christoph; Kaila, Neelu; Papaioannou, Nikolaos; Thorarensen, Atli

    2012-05-01

    Discovery of small molecular inhibitors for treatment of rheumatoid arthritis is a major ongoing effort within the pharmaceutical industry. Spleen tyrosine kinase (SYK) is one of leading small molecular targets with regard to clinical development primarlly due to efforts by Rigel and Portola. In this review, we provide a comprehensive overview of the SYK patent landscape. The patent literature we evaluated relates to any organization that has filed applications that imply that SYK is the intended target. The interest in SYK was initiated in the early 2000's with many organizations, including several large pharmaceutical companies, and has been active for years. In general, the structural theme of most of the compounds in these applications is a traditional ATP competitive inhibitor with each organization having a different hinge binding element. In general, the attachment to the hinge is an aryl amine that is decorated with a solubilizing group. The other substituents are broadly variable across the numerous companies indicating that SYK has significant flexibility in its interactions in that portion of the kinase. This overview of the SYK patent literature and the learnings of the inhibitors' substitution patterns would be an important reference for anyone working in this area.

  15. ZAP-70 and p72syk are signaling response elements through MHC class II molecules

    DEFF Research Database (Denmark)

    Kanner, S B; Grosmaire, L S; Blake, J

    1995-01-01

    Ligation of major histocompatibility complex (MHC) class II antigens expressed on antigen-activated human CD4+ T-lymphocytes induces early signal transduction events including the activation of tyrosine kinases, the tyrosine phosphorylation of phospholipase-C gamma 1 and the mobilization of intra......Ligation of major histocompatibility complex (MHC) class II antigens expressed on antigen-activated human CD4+ T-lymphocytes induces early signal transduction events including the activation of tyrosine kinases, the tyrosine phosphorylation of phospholipase-C gamma 1 and the mobilization...... of intracellular calcium. Similar responses have been observed in B-cells following stimulation of MHC class II molecules, including the increased production of intracellular cAMP. In this report, we demonstrate that the ZAP-70 tyrosine kinase is a responsive signaling element following cross-linking of HLA...... by herbimycin A. MHC class II ligation on B-lymphocytes resulted in cell death, which was both qualitatively distinct from Fas-induced apoptosis and partially protected by herbimycin A pretreatment. Thus, ligation of MHC class II molecules expressed on human lymphocytes stimulates the ZAP-70/p72syk family...

  16. Proteomic and Genetic Approaches Identify Syk as an AML Target

    Science.gov (United States)

    Hahn, Cynthia K.; Berchuck, Jacob E.; Ross, Kenneth N.; Kakoza, Rose M.; Clauser, Karl; Schinzel, Anna C.; Ross, Linda; Galinsky, Ilene; Davis, Tina N.; Silver, Serena J.; Root, David E.; Stone, Richard M.; DeAngelo, Daniel J.; Carroll, Martin; Hahn, William C.; Carr, Steven A.; Golub, Todd R.; Kung, Andrew L.; Stegmaier, Kimberly

    2009-01-01

    SUMMARY Cell-based screening can facilitate rapid identification of compounds inducing complex cellular phenotypes. Advancing a compound toward the clinic, however, generally requires identification of precise mechanisms of action. We previously found that epidermal growth factor receptor (EGFR) inhibitors induce acute myeloid leukemia (AML) differentiation via a non-EGFR mechanism. In this report, we integrated proteomic and RNAi-based strategies to identify their off-target anti-AML mechanism. These orthogonal approaches identified Syk as a target in AML. Genetic and pharmacological inactivation of Syk with a drug in clinical trial for other indications promoted differentiation of AML cells and attenuated leukemia growth in vivo. These results demonstrate the power of integrating diverse chemical, proteomic, and genomic screening approaches to identify therapeutic strategies for cancer. PMID:19800574

  17. The Dietary Flavonoid Kaempferol Mediates Anti-Inflammatory Responses via the Src, Syk, IRAK1, and IRAK4 Molecular Targets

    Directory of Open Access Journals (Sweden)

    Shi Hyoung Kim

    2015-01-01

    Full Text Available Even though a lot of reports have suggested the anti-inflammatory activity of kaempferol (KF in macrophages, little is known about its exact anti-inflammatory mode of action and its immunopharmacological target molecules. In this study, we explored anti-inflammatory activity of KF in LPS-treated macrophages. In particular, molecular targets for KF action were identified by using biochemical and molecular biological analyses. KF suppressed the release of nitric oxide (NO and prostaglandin E2 (PGE2, downregulated the cellular adhesion of U937 cells to fibronectin (FN, neutralized the generation of radicals, and diminished mRNA expression levels of inflammatory genes encoding inducible NO synthase (iNOS, TNF-α, and cyclooxygenase- (COX- 2 in lipopolysaccharide- (LPS- and sodium nitroprusside- (SNP- treated RAW264.7 cells and peritoneal macrophages. KF reduced NF-κB (p65 and p50 and AP-1 (c-Jun and c-Fos levels in the nucleus and their transcriptional activity. Interestingly, it was found that Src, Syk, IRAK1, and IRAK4 responsible for NF-κB and AP-1 activation were identified as the direct molecular targets of KF by kinase enzyme assays and by measuring their phosphorylation patterns. KF was revealed to have in vitro and in vivo anti-inflammatory activity by the direct suppression of Src, Syk, IRAK1, and IRAK4, involved in the activation of NF-κB and AP-1.

  18. Tumor suppressor function of Syk in human MCF10A in vitro and normal mouse mammary epithelium in vivo.

    Science.gov (United States)

    Sung, You Me; Xu, Xuehua; Sun, Junfeng; Mueller, Duane; Sentissi, Kinza; Johnson, Peter; Urbach, Elana; Seillier-Moiseiwitsch, Françoise; Johnson, Michael D; Mueller, Susette C

    2009-10-15

    The normal function of Syk in epithelium of the developing or adult breast is not known, however, Syk suppresses tumor growth, invasion, and metastasis in breast cancer cells. Here, we demonstrate that in the mouse mammary gland, loss of one Syk allele profoundly increases proliferation and ductal branching and invasion of epithelial cells through the mammary fat pad during puberty. Mammary carcinomas develop by one year. Syk also suppresses proliferation and invasion in vitro. siRNA or shRNA knockdown of Syk in MCF10A breast epithelial cells dramatically increased proliferation, anchorage independent growth, cellular motility, and invasion, with formation of functional, extracellular matrix-degrading invadopodia. Morphological and gene microarray analysis following Syk knockdown revealed a loss of luminal and differentiated epithelial features with epithelial to mesenchymal transition and a gain in invadopodial cell surface markers CD44, CD49F, and MMP14. These results support the role of Syk in limiting proliferation and invasion of epithelial cells during normal morphogenesis, and emphasize the critical role of Syk as a tumor suppressor for breast cancer. The question of breast cancer risk following systemic anti-Syk therapy is raised since only partial loss of Syk was sufficient to induce mammary carcinomas.

  19. Tumor suppressor function of Syk in human MCF10A in vitro and normal mouse mammary epithelium in vivo.

    Directory of Open Access Journals (Sweden)

    You Me Sung

    2009-10-01

    Full Text Available The normal function of Syk in epithelium of the developing or adult breast is not known, however, Syk suppresses tumor growth, invasion, and metastasis in breast cancer cells. Here, we demonstrate that in the mouse mammary gland, loss of one Syk allele profoundly increases proliferation and ductal branching and invasion of epithelial cells through the mammary fat pad during puberty. Mammary carcinomas develop by one year. Syk also suppresses proliferation and invasion in vitro. siRNA or shRNA knockdown of Syk in MCF10A breast epithelial cells dramatically increased proliferation, anchorage independent growth, cellular motility, and invasion, with formation of functional, extracellular matrix-degrading invadopodia. Morphological and gene microarray analysis following Syk knockdown revealed a loss of luminal and differentiated epithelial features with epithelial to mesenchymal transition and a gain in invadopodial cell surface markers CD44, CD49F, and MMP14. These results support the role of Syk in limiting proliferation and invasion of epithelial cells during normal morphogenesis, and emphasize the critical role of Syk as a tumor suppressor for breast cancer. The question of breast cancer risk following systemic anti-Syk therapy is raised since only partial loss of Syk was sufficient to induce mammary carcinomas.

  20. Increased Syk phosphorylation leads to overexpression of TRAF6 in peripheral B cells of patients with systemic lupus erythematosus.

    Science.gov (United States)

    Iwata, S; Yamaoka, K; Niiro, H; Jabbarzadeh-Tabrizi, S; Wang, S-P; Kondo, M; Yoshikawa, M; Akashi, K; Tanaka, Y

    2015-06-01

    Activation of B cells is a hallmark of systemic lupus erythematosus (SLE). Syk and TRAF6 are key signaling molecules in B-cell activation through BCR and CD40/TLR, respectively. Nevertheless, whether expression of Syk and TRAF6 is altered in SLE B cells remains unknown. Phosphorylation and/or expression of Syk and TRAF6 were analyzed by flow cytometry in peripheral blood mononuclear cells isolated from SLE patients. Pronounced phosphorylation and expression of Syk were noted in B cells from SLE patients compared with healthy donors. Levels of Syk phosphorylation correlated with the disease activity score. TRAF6 was significantly over-expressed in B cells of SLE patients as compared with healthy donors, and significant correlation of levels of TRAF6 expression and Syk phosphorylation was observed in SLE patients. Levels of TRAF6 expression were more pronounced in CD27+ memory B cells than in CD27-naïve B cells. In vitro treatment of SLE B cells with a Syk inhibitor (BAY61-3606) reduced Syk phosphorylation as well as TRAF6 expression. Our results suggest that the activated Syk-mediated TRAF6 pathway leads to aberrant activation of B cells in SLE, and also highlight Syk as a potential target for B-cell-mediated processes in SLE. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. More on supersymmetric and 2d analogs of the SYK model

    Science.gov (United States)

    Murugan, Jeff; Stanford, Douglas; Witten, Edward

    2017-08-01

    In this paper, we explore supersymmetric and 2d analogs of the SYK model. We begin by working out a basis of (super)conformal eigenfunctions appropriate for expanding a four-point function. We use this to clarify some details of the 1d supersymmetric SYK model. We then introduce new bosonic and supersymmetric analogs of SYK in two dimensions. These theories consist of N fields interacting with random q-field interactions. Although models built entirely from bosons appear to be problematic, we find a supersymmetric model that flows to a large N CFT with interaction strength of order one. We derive an integral formula for the four-point function at order 1 /N , and use it to compute the central charge, chaos exponent and some anomalous dimensions. We describe a problem that arises if one tries to find a 2d SYK-like CFT with a continuous global symmetry.

  2. Anomalous constitutive Src kinase activity promotes B lymphoma survival and growth

    OpenAIRE

    Ke, Jiyuan; Chelvarajan, R Lakshman; Sindhava, Vishal; Robertson, Darrell A; Lekakis, Lazaros; Jennings, C Darrell; Bondada, Subbarao

    2009-01-01

    Abstract Background Previously we have shown that B cell receptor (BCR) expression and B cell receptor signaling pathways are important for the basal growth of B lymphoma cells. In particular we have shown that the activation of Syk, a non-src family protein tyrosine kinase and the mitogen activated protein kinases (MAPK), ERK and JNK that mediate BCR signals are required for the constitutive growth of B lymphoma cells. Since src family protein tyrosine kinases (SFKs) like Lyn are known to be...

  3. CR3 and Dectin-1 Collaborate in Macrophage Cytokine Response through Association on Lipid Rafts and Activation of Syk-JNK-AP-1 Pathway.

    Directory of Open Access Journals (Sweden)

    Juin-Hua Huang

    2015-07-01

    Full Text Available Collaboration between heterogeneous pattern recognition receptors (PRRs leading to synergistic coordination of immune response is important for the host to fight against invading pathogens. Although complement receptor 3 (CR3 and Dectin-1 are major PRRs to detect fungi, crosstalk between these two receptors in antifungal immunity is largely undefined. Here we took advantage of Histoplasma capsulatum which is known to interact with both CR3 and Dectin-1 and specific particulate ligands to study the collaboration of CR3 and Dectin-1 in macrophage cytokine response. By employing Micro-Western Array (MWA, genetic approach, and pharmacological inhibitors, we demonstrated that CR3 and Dectin-1 act collaboratively to trigger macrophage TNF and IL-6 response through signaling integration at Syk kinase, allowing subsequent enhanced activation of Syk-JNK-AP-1 pathway. Upon engagement, CR3 and Dectin-1 colocalize and form clusters on lipid raft microdomains which serve as a platform facilitating their cooperation in signaling activation and cytokine production. Furthermore, in vivo studies showed that CR3 and Dectin-1 cooperatively participate in host defense against disseminated histoplasmosis and instruct adaptive immune response. Taken together, our findings define the mechanism of receptor crosstalk between CR3 and Dectin-1 and demonstrate the importance of their collaboration in host defense against fungal infection.

  4. ITAM receptor-mediated generation of reactive oxygen species in human platelets occurs via Syk-dependent and Syk-independent pathways.

    Science.gov (United States)

    Arthur, J F; Qiao, J; Shen, Y; Davis, A K; Dunne, E; Berndt, M C; Gardiner, E E; Andrews, R K

    2012-06-01

    Ligation of the platelet-specific collagen receptor, GPVI/FcRγ, causes rapid, transient disulfide-dependent homodimerization, and the production of intracellular reactive oxygen species (ROS) generated by the NADPH oxidase, linked to GPVI via TRAF4. The aim of this study was to evaluate the role of early signaling events in ROS generation following engagement of either GPVI/FcRγ or a second immunoreceptor tyrosine-based activation motif (ITAM)-containing receptor on platelets, FcγRIIa. Using an H(2) DCF-DA-based flow cytometric assay to measure intracellular ROS, we show that treatment of platelets with either the GPVI agonists, collagen-related peptide (CRP) or convulxin (Cvx), or the FcγRIIa agonist 14A2, increased intraplatelet ROS; other platelet agonists such as ADP and TRAP did not. Basal ROS in platelet-rich plasma from 14 healthy donors displayed little inter-individual variability. CRP, Cvx or 14A2 induced an initial burst of ROS within 2 min followed by additional ROS reaching a plateau after 15-20 min. The Syk inhibitor BAY61-3606, which blocks ITAM-dependent signaling, had no effect on the initial ROS burst, but completely inhibited the second phase. Together, these results show for the first time that ROS generation downstream of GPVI or FcγRIIa consists of two distinct phases: an initial Syk-independent burst followed by additional Syk-dependent generation. © 2012 International Society on Thrombosis and Haemostasis.

  5. Kinase inhibitors: a new class of antirheumatic drugs

    Directory of Open Access Journals (Sweden)

    Kyttaris VC

    2012-09-01

    Full Text Available Vasileios C KyttarisDivision of Rheumatology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USAAbstract: The outlook for patients with rheumatoid arthritis has improved significantly over the last three decades with the use of disease-modifying antirheumatic drugs. However, despite the use of methotrexate, cytokine inhibitors, and molecules targeting T and B cells, a percentage of patients do not respond or lose their response over time. The autoimmune process in rheumatoid arthritis depends on activation of immune cells, which utilize intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. In the past decade, small molecules targeting several kinases, such as p38 MAPK, Syk, and JAK have been developed. Several p38 MAPK inhibitors proved ineffective in treating rheumatoid arthritis. The Syk inhibitor, fostamatinib, proved superior to placebo in Phase II trials and is currently under Phase III investigation. Tofacitinib, a JAK1/3 inhibitor, was shown to be efficacious in two Phase III trials, while VX-509, a JAK3 inhibitor, showed promising results in a Phase II trial. Fostamatinib and tofacitinib were associated with increased rates of infection, elevation of liver enzymes, and neutropenia. Moreover, fostamatinib caused elevations of blood pressure and diarrhea, while tofacitinib was associated with an increase in creatinine and elevation of lipid levels.Keywords: rheumatoid arthritis, kinase inhibitors, mitogen-activated phosphokinase p38, spleen tyrosine kinase, Janus kinases

  6. Polyoxygenated cholesterol ester hydroperoxide activates TLR4 and SYK dependent signaling in macrophages.

    Directory of Open Access Journals (Sweden)

    Soo-Ho Choi

    Full Text Available Oxidation of low-density lipoprotein (LDL is one of the major causative mechanisms in the development of atherosclerosis. In previous studies, we showed that minimally oxidized LDL (mmLDL induced inflammatory responses in macrophages, macropinocytosis and intracellular lipid accumulation and that oxidized cholesterol esters (OxCEs were biologically active components of mmLDL. Here we identified a specific OxCE molecule responsible for the biological activity of mmLDL and characterized signaling pathways in macrophages in response to this OxCE. Using liquid chromatography - tandem mass spectrometry and biological assays, we identified an oxidized cholesteryl arachidonate with bicyclic endoperoxide and hydroperoxide groups (BEP-CE as a specific OxCE that activates macrophages in a TLR4/MD-2-dependent manner. BEP-CE induced TLR4/MD-2 binding and TLR4 dimerization, phosphorylation of SYK, ERK1/2, JNK and c-Jun, cell spreading and uptake of dextran and native LDL by macrophages. The enhanced macropinocytosis resulted in intracellular lipid accumulation and macrophage foam cell formation. Bone marrow-derived macrophages isolated from TLR4 and SYK knockout mice did not respond to BEP-CE. The presence of BEP-CE was demonstrated in human plasma and in the human plaque material captured in distal protection devices during percutaneous intervention. Our results suggest that BEP-CE is an endogenous ligand that activates the TLR4/SYK signaling pathway. Because BEP-CE is present in human plasma and human atherosclerotic lesions, BEP-CE-induced and TLR4/SYK-mediated macrophage responses may contribute to chronic inflammation in human atherosclerosis.

  7. Aspergillus Cell Wall Chitin Induces Anti- and Proinflammatory Cytokines in Human PBMCs via the Fc-γ Receptor/Syk/PI3K Pathway

    Science.gov (United States)

    Becker, K. L.; Aimanianda, V.; Wang, X.; Gresnigt, M. S.; Ammerdorffer, A.; Jacobs, C. W.; Gazendam, R. P.; Joosten, L. A. B.; Netea, M. G.

    2016-01-01

    ABSTRACT Chitin is an important cell wall component of Aspergillus fumigatus conidia, of which hundreds are inhaled on a daily basis. Previous studies have shown that chitin has both anti- and proinflammatory properties; however the exact mechanisms determining the inflammatory signature of chitin are poorly understood, especially in human immune cells. Human peripheral blood mononuclear cells were isolated from healthy volunteers and stimulated with chitin from Aspergillus fumigatus. Transcription and production of the proinflammatory cytokine interleukin-1β (IL-1β) and the anti-inflammatory cytokine IL-1 receptor antagonist (IL-1Ra) were measured from the cell culture supernatant by quantitative PCR (qPCR) or enzyme-linked immunosorbent assay (ELISA), respectively. Chitin induced an anti-inflammatory signature characterized by the production of IL-1Ra in the presence of human serum, which was abrogated in immunoglobulin-depleted serum. Fc-γ-receptor-dependent recognition and phagocytosis of IgG-opsonized chitin was identified as a novel IL-1Ra-inducing mechanism by chitin. IL-1Ra production induced by chitin was dependent on Syk kinase and phosphatidylinositol 3-kinase (PI3K) activation. In contrast, costimulation of chitin with the pattern recognition receptor (PRR) ligands lipopolysaccharide, Pam3Cys, or muramyl dipeptide, but not β-glucan, had synergistic effects on the induction of proinflammatory cytokines by human peripheral blood mononuclear cells (PBMCs). In conclusion, chitin can have both pro- and anti-inflammatory properties, depending on the presence of pathogen-associated molecular patterns and immunoglobulins, thus explaining the various inflammatory signatures reported for chitin. PMID:27247234

  8. Tyrosine kinase Btk regulates E-selectin–mediated integrin activation and neutrophil recruitment by controlling phospholipase C (PLC) γ2 and PI3Kγ pathways

    Science.gov (United States)

    Mueller, Helena; Stadtmann, Anika; Van Aken, Hugo; Hirsch, Emilio; Wang, Demin; Ley, Klaus

    2010-01-01

    Selectins mediate leukocyte rolling, trigger β2-integrin activation, and promote leukocyte recruitment into inflamed tissue. E-selectin binding to P-selectin glycoprotein ligand 1 (PSGL-1) leads to activation of an immunoreceptor tyrosine-based activation motif (ITAM)–dependent pathway, which in turn activates the spleen tyrosine kinase (Syk). However, the signaling pathway linking Syk to integrin activation after E-selectin engagement is unknown. To identify the pathway, we used different gene-deficient mice in autoperfused flow chamber, intravital microscopy, peritonitis, and biochemical studies. We report here that the signaling pathway downstream of Syk divides into a phospholipase C (PLC) γ2– and phosphoinositide 3-kinase (PI3K) γ–dependent pathway. The Tec family kinase Bruton tyrosine kinase (Btk) is required for activating both pathways, generating inositol-3,4,5-trisphosphate (IP3), and inducing E-selectin–mediated slow rolling. Inhibition of this signal-transduction pathway diminished Gαi-independent leukocyte adhesion to and transmigration through endothelial cells in inflamed postcapillary venules of the cremaster. Gαi-independent neutrophil recruitment into the inflamed peritoneal cavity was reduced in Btk−/− and Plcg2−/− mice. Our data demonstrate the functional importance of this newly identified signaling pathway mediated by E-selectin engagement. PMID:20167705

  9. Discovery of platyhelminth-specific α/β-integrin families and evidence for their role in reproduction in Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Svenja Beckmann

    Full Text Available In all metazoa, the response of cells to molecular stimuli from their environment represents a fundamental principle of regulatory processes controlling cell growth and differentiation. Among the membrane-linked receptors mediating extracellular communication processes are integrin receptors. Besides managing adhesion to the extracellular matrix or to other cells, they arrange information flow into the cells by activating intracellular signaling pathways often acting synergistically through cooperation with growth factor receptors. Although a wealth of information exists on integrins in different model organisms, there is a big gap of knowledge for platyhelminths. Here we report on the in silico detection and reconstruction of α and β integrins from free-living and parasitic platyhelminths, which according to structural and phylogenetic analyses form specific clades separate from each other and from further metazoan integrins. As representative orthologs of parasitic platyhelminths we have cloned one beta-integrin (Smβ-Int1 and four alpha-integrins (Smα-Int1 - Smα-Int4 from Schistosoma mansoni; they were characterized by molecular and biochemical analyses. Evidence is provided that Smβ-Int1 interacts and co-localizes in the reproductive organs with known schistosome cellular tyrosine kinases (CTKs, of which the Syk kinase SmTK4 appeared to be the strongest interaction partner as shown by yeast two-hybrid analyses and coimmunoprecipitation experiments. By a novel RNAi approach with adult schistosomes in vitro we demonstrate for the first time multinucleated oocytes in treated females, indicating a decisive role Smβ-Int1 during oogenesis as phenotypically analyzed by confocal laser scanning microscopy (CLSM. Our findings provide a first comprehensive overview about platyhelminth integrins, of which the parasite group exhibits unique features allowing a clear distinction from the free-living groups. Furthermore, we shed first lights on the

  10. Borrelia-induced cytokine production is mediated by spleen tyrosine kinase (Syk) but is Dectin-1 and Dectin-2 independent

    NARCIS (Netherlands)

    Oosting, M.; Buffen, K.; Cheng, S.C.; Verschueren, I.C.; Koentgen, F.; Veerdonk, F.L. van de; Netea, M.G.; Joosten, L.A.B.

    2015-01-01

    Although it is known that Borrelia species express sugar-like structures on their outer surface, not much is known about the role of these structures in immune recognition by host cells. Fungi, like Candida albicans, are mainly recognized by C-type lectin receptors, in specific Dectin-1 and

  11. Dual Role of the Tyrosine Kinase Syk in Regulation of Toll-Like Receptor Signaling in Plasmacytoid Dendritic Cells

    Czech Academy of Sciences Publication Activity Database

    Aouar, B.; Kovářová, D.; Letard, S.; Font-Haro, A.; Florentin, J.; Weber, Jan; Durantel, D.; Chaperot, L.; Plumas, J.; Trejbalová, K.; Hejnar, J.; Nunes, J.A.; Olive, D.; Dubreuil, P.; Hirsch, Ivan; Stranska, R.

    2016-01-01

    Roč. 11, č. 6 (2016), č. článku e0156063. E-ISSN 1932-6203 Institutional support: RVO:61388963 Keywords : hepatitis C virus * B virus * alpha Subject RIV: EE - Microbiology, Virology Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0156063

  12. Dual Role of the Tyrosine Kinase Syk in Regulation of Toll-Like Receptor Signaling in Plasmacytoid Dendritic Cells

    Czech Academy of Sciences Publication Activity Database

    Aouar, B.; Kovářová, Denisa; Letard, S.; Font-Haro, Albert; Florentin, J.; Weber, J.; Durantel, D.; Chaperot, L.; Plumas, J.; Trejbalová, Kateřina; Hejnar, Jiří; Nunes, J.A.; Olive, D.; Dubreuil, P.; Hirsch, Ivan; Stranska, R.

    2016-01-01

    Roč. 11, č. 6 (2016), č. článku e0156063. E-ISSN 1932-6203 R&D Projects: GA ČR GA14-32547S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:68378050 Keywords : hepatitis-c virus * b-virus * alpha * interferon * secretion * responses Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.806, year: 2016

  13. The non-receptor tyrosine kinase Tec controls assembly and activity of the noncanonical caspase-8 inflammasome.

    Science.gov (United States)

    Zwolanek, Florian; Riedelberger, Michael; Stolz, Valentina; Jenull, Sabrina; Istel, Fabian; Köprülü, Afitap Derya; Ellmeier, Wilfried; Kuchler, Karl

    2014-12-01

    Tec family kinases are intracellular non-receptor tyrosine kinases implicated in numerous functions, including T cell and B cell regulation. However, a role in microbial pathogenesis has not been described. Here, we identified Tec kinase as a novel key mediator of the inflammatory immune response in macrophages invaded by the human fungal pathogen C. albicans. Tec is required for both activation and assembly of the noncanonical caspase-8, but not of the caspase-1 inflammasome, during infections with fungal but not bacterial pathogens, triggering the antifungal response through IL-1β. Furthermore, we identify dectin-1 as the pathogen recognition receptor being required for Syk-dependent Tec activation. Hence, Tec is a novel innate-specific inflammatory kinase, whose genetic ablation or inhibition by small molecule drugs strongly protects mice from fungal sepsis. These data demonstrate a therapeutic potential for Tec kinase inhibition to combat invasive microbial infections by attenuating the host inflammatory response.

  14. Calcium phosphate particles stimulate interleukin-1β release from human vascular smooth muscle cells: A role for spleen tyrosine kinase and exosome release.

    Science.gov (United States)

    Dautova, Yana; Kapustin, Alexander N; Pappert, Kevin; Epple, Matthias; Okkenhaug, Hanneke; Cook, Simon J; Shanahan, Catherine M; Bootman, Martin D; Proudfoot, Diane

    2018-02-01

    Calcium phosphate (CaP) particle deposits are found in several inflammatory diseases including atherosclerosis and osteoarthritis. CaP, and other forms of crystals and particles, can promote inflammasome formation in macrophages leading to caspase-1 activation and secretion of mature interleukin-1β (IL-1β). Given the close association of small CaP particles with vascular smooth muscle cells (VSMCs) in atherosclerotic fibrous caps, we aimed to determine if CaP particles affected pro-inflammatory signalling in human VSMCs. Using ELISA to measure IL-1β release from VSMCs, we demonstrated that CaP particles stimulated IL-1β release from proliferating and senescent human VSMCs, but with substantially greater IL-1β release from senescent cells; this required caspase-1 activity but not LPS-priming of cells. Potential inflammasome agonists including ATP, nigericin and monosodium urate crystals did not stimulate IL-1β release from VSMCs. Western blot analysis demonstrated that CaP particles induced rapid activation of spleen tyrosine kinase (SYK) (increased phospho-Y525/526). The SYK inhibitor R406 reduced IL-1β release and caspase-1 activation in CaP particle-treated VSMCs, indicating that SYK activation occurs upstream of and is required for caspase-1 activation. In addition, IL-1β and caspase-1 colocalised in intracellular endosome-like vesicles and we detected IL-1β in exosomes isolated from VSMC media. Furthermore, CaP particle treatment stimulated exosome secretion by VSMCs in a SYK-dependent manner, while the exosome-release inhibitor spiroepoxide reduced IL-1β release. CaP particles stimulate SYK and caspase-1 activation in VSMCs, leading to the release of IL-1β, at least in part via exosomes. These novel findings in human VSMCs highlight the pro-inflammatory and pro-calcific potential of microcalcification. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. A spleen tyrosine kinase inhibitor attenuates the proliferation and migration of vascular smooth muscle cells

    Directory of Open Access Journals (Sweden)

    Hyang‑Hee Seo

    Full Text Available Abstract Background Pathologic vascular smooth muscle cell (VSMC proliferation and migration after vascular injury promotes the development of occlusive vascular disease. Therefore, an effective chemical agent to suppress aberrant proliferation and migration of VSMCs can be a potential therapeutic modality for occlusive vascular disease such as atherosclerosis and restenosis. To find an anti-proliferative chemical agent for VSMCs, we screened an in-house small molecule library, and the selected small molecule was further validated for its anti-proliferative effect on VSMCs using multiple approaches, such as cell proliferation assays, wound healing assays, transwell migration assays, and ex vivo aortic ring assay. Results Among 43 initially screened small molecule inhibitors of kinases that have no known anti-proliferative effect on VSMCs, a spleen tyrosine kinase (Syk inhibitor (BAY61-3606 showed significant anti-proliferative effect on VSMCs. Further experiments indicated that BAY61 attenuated the VSMC proliferation in both concentration- and time-dependent manner, and it also significantly suppressed the migration of VSMCs as assessed by both wound healing assays and transwell assays. Additionally, BAY61 suppressed the sprouting of VSMCs from endothelium-removed aortic rings. Conclusion The present study identified a Syk kinase inhibitor as a potent VSMC proliferation and migration inhibitor and warrants further studies to elucidate its underlying molecular mechanisms, such as its primary target, and to validate its in vivo efficacy as a therapeutic agent for restenosis and atherosclerosis.

  16. Temporal quantitation of mutant Kit tyrosine kinase signaling attenuated by a novel thiophene kinase inhibitor OSI-930.

    Science.gov (United States)

    Petti, Filippo; Thelemann, April; Kahler, Jen; McCormack, Siobhan; Castaldo, Linda; Hunt, Tony; Nuwaysir, Lydia; Zeiske, Lynn; Haack, Herbert; Sullivan, Laura; Garton, Andrew; Haley, John D

    2005-08-01

    OSI-930, a potent thiophene inhibitor of the Kit, KDR, and platelet-derived growth factor receptor tyrosine kinases, was used to selectively inhibit tyrosine phosphorylation downstream of juxtamembrane mutant Kit in the mast cell leukemia line HMC-1. Inhibition of Kit kinase activity resulted in a rapid dephosphorylation of Kit and inhibition of the downstream signaling pathways. Attenuation of Ras-Raf-Erk (phospho-Erk, phospho-p38), phosphatidyl inositol-3' kinase (phospho-p85, phospho-Akt, phospho-S6), and signal transducers and activators of transcription signaling pathways (phospho-STAT3/5/6) were measured by affinity liquid chromatography tandem mass spectrometry, by immunoblot, and by tissue microarrays of fixed cell pellets. To more globally define additional components of Kit signaling temporally altered by kinase inhibition, a novel multiplex quantitative isobaric peptide labeling approach was used. This approach allowed clustering of proteins by temporal expression patterns. Kit kinase, which dephosphorylates rapidly upon kinase inhibition, was shown to regulate both Shp-1 and BDP-1 tyrosine phosphatases and the phosphatase-interacting protein PSTPIP2. Interactions with SH2 domain adapters [growth factor receptor binding protein 2 (Grb2), Cbl, Slp-76] and SH3 domain adapters (HS1, cortactin, CD2BP3) were attenuated by inhibition of Kit kinase activity. Functional crosstalk between Kit and the non-receptor tyrosine kinases Fes/Fps, Fer, Btk, and Syk was observed. Inhibition of Kit modulated phosphorylation-dependent interactions with pathways controlling focal adhesion (paxillin, leupaxin, p130CAS, FAK1, the Src family kinase Lyn, Wasp, Fhl-3, G25K, Ack-1, Nap1, SH3P12/ponsin) and septin-actin complexes (NEDD5, cdc11, actin). The combined use of isobaric protein quantitation and expression clustering, immunoblot, and tissue microarray strategies allowed temporal measurement signaling pathways modulated by mutant Kit inhibition in a model of mast cell

  17. Syk - GTP RAC-1 mediated immune-stimulatory effect of Cuscuta epithymum, Ipomoea batata and Euphorbia hirta plant extracts.

    Science.gov (United States)

    Sudam, Vanitha Sagar; Potnuri, Ajay Godwin; Subhashini, N J Prameela

    2017-12-01

    Polymorphonuclear neutrophils (PMNn) are the pivotal mediators of phagocytosis. In addition to neutropenia, impaired neutrophilic function is associated with pathological conditions and immuno-deficiencies. Henceforth, Immuno-stimulatory strategies targeting neutrophilic function are indeed powerful tools in combating obstinate infections. In appreciation towards the usefulness of herbal medicines in therapeutic scenario, the present study was carried out to analyse the immuno-stimulatory effect of Cuscuta epithymum, Ipomoea batata and Euphorbia hirta using in-vitro and in-vivo rodent experimental models. Throughout the experimentation, phagocytosis was studied and expressed as phagocytotic index and percentage phagocytosis. Different extracts of these plants were initially screened for their potency to induce phagocytosis in PMNn and the methanolic fractions, which are effective, were considered for further experimentation.The phagocytosis stimulation by the methanolic extracts was compared with the standard Granulocyte Macrophage - Colony Stimulating Factor (GM-CSF) at a dose of 65ng/ml. Immunoblotting analysis shown that the methanolic extracts induce the phosphorylation of Syk which in turn phosphorylates GDP-RAC-1, hinting the possible mechanism of action. Following these in vitro investigations, the potency of methanolic extracts was assessed using rat model by performing carbon clearance assay, Delayed Type Hypersensitivity and antibody titre.The phosphorylation status of Syk and GDP-RAC-1 was also assessed in the edematous fluid collected from the right hind paw. In vivo findings were in agreement with the in vitro findings by presenting an improved immune response and increased phosphorylation of Syk and GDP-RAC-1. Conclusively, this study provides the initial insights into the therapeutic implications of the tropical plants in inducing phagocytosis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  18. Immunotoxicity assessment for the novel Spleen tyrosine kinase inhibitor R406

    International Nuclear Information System (INIS)

    Zhu Yanhong; Herlaar, Ellen; Masuda, Esteban S.; Burleson, Gary R.; Nelson, Andrew J.; Grossbard, Elliott B.; Clemens, George R.

    2007-01-01

    Spleen tyrosine kinase (Syk) is a novel pharmaceutical target for treatment of allergic, autoimmune, and neoplastic disorders. Previous studies have indicated that Syk signaling plays critical roles in regulating the lymphohematopoietic system. These observations prompted us to investigate whether inhibition of Syk would promote immunotoxicity. In a series of studies, rats were treated orally with R406, at dose levels up to and including 100 mg/kg/day (or its prodrug R788 at dose levels up to and including 100 mg/kg/day, reduced to 50 mg/kg/day for females as MTD was exceeded), a potent Syk inhibitor, twice daily for 28 days. In addition to standard toxicological assessments, immunophenotyping by flow cytometric analysis, and a study of humoral immune response measuring anti-KLH IgM and IgG levels, were undertaken. Other immunotoxicity studies included three host resistance models in female Balb/c mice to further ascertain effects of R406 on innate and acquired immunity. Following R406 treatment, expected immunomodulating effects (e.g., decreased thymic and spleen weight, hypocellularity of bone marrow, and reduced lymphocyte counts, including T and B cells) were observed in the rat studies. These changes essentially resolved during a 14-day treatment-free recovery period. A KLH challenge in rats demonstrated no adverse effects on IgG or IgM response. R788/406, administered orally at dose levels up to and including 80 mg/kg/day for 28 days, did not affect bacterial or viral clearance in the Listeria, Streptococcal, or Influenza host resistance mouse models, respectively. This correlated with previous in vitro macrophage and neutrophil function assays (assessing migration, phagocytosis, oxidative burst and microbicidal activity), which revealed that R406 did not adversely affect macrophage or neutrophil function in innate immune responses. Collectively, these results demonstrate that R406 has minimal functional immunotoxicity notwithstanding its lymphocytopenic

  19. Anchor-based classification and type-C inhibitors for tyrosine kinases

    Science.gov (United States)

    Hsu, Kai-Cheng; Sung, Tzu-Ying; Lin, Chih-Ta; Chiu, Yi-Yuan; Hsu, John T.-A.; Hung, Hui-Chen; Sun, Chung-Ming; Barve, Indrajeet; Chen, Wen-Liang; Huang, Wen-Chien; Huang, Chin-Ting; Chen, Chun-Hwa; Yang, Jinn-Moon

    2015-01-01

    Tyrosine kinases regulate various biological processes and are drug targets for cancers. At present, the design of selective and anti-resistant inhibitors of kinases is an emergent task. Here, we inferred specific site-moiety maps containing two specific anchors to uncover a new binding pocket in the C-terminal hinge region by docking 4,680 kinase inhibitors into 51 protein kinases, and this finding provides an opportunity for the development of kinase inhibitors with high selectivity and anti-drug resistance. We present an anchor-based classification for tyrosine kinases and discover two type-C inhibitors, namely rosmarinic acid (RA) and EGCG, which occupy two and one specific anchors, respectively, by screening 118,759 natural compounds. Our profiling reveals that RA and EGCG selectively inhibit 3% (EGFR and SYK) and 14% of 64 kinases, respectively. According to the guide of our anchor model, we synthesized three RA derivatives with better potency. These type-C inhibitors are able to maintain activities for drug-resistant EGFR and decrease the invasion ability of breast cancer cells. Our results show that the type-C inhibitors occupying a new pocket are promising for cancer treatments due to their kinase selectivity and anti-drug resistance. PMID:26077136

  20. Dual functions of Bruton's tyrosine kinase and Tec kinase during Fcgamma receptor-induced signaling and phagocytosis.

    Science.gov (United States)

    Jongstra-Bilen, Jenny; Puig Cano, Adrianet; Hasija, Manvi; Xiao, Haiyan; Smith, C I Edvard; Cybulsky, Myron I

    2008-07-01

    Tec family nonreceptor tyrosine kinases are expressed by hematopoietic cells, activate phospholipase C (PLC)gamma, and regulate cytoskeletal rearrangement, yet their role in FcgammaR-induced signaling and phagocytosis remains unknown. We demonstrate in this study that Bruton's tyrosine kinase (Btk) and Tec, the only Tec kinases expressed by RAW 264.7 cells, are activated throughout phagocytosis. Activated Btk and Tec kinase accumulate at an early stage at the base of phagocytic cups and inhibition of their activity by the specific inhibitor LFM-A13 or expression by small interfering RNA significantly inhibited FcgammaR-induced phagocytosis. Similarly, a significant role for these kinases in phagocytosis was found in primary macrophages. FcgammaR-induced activation of Mac-1, which is required for optimal phagocytosis, was markedly inhibited and our findings suggest that the roles of kinases Btk and Tec in Mac-1 activation account for their functions in the early stages of phagocytosis. Initial activation of PLCgamma2, the predominant PLC isoform in RAW 264.7 cells, is dependent on Syk. In contrast, a late and prolonged activation of PLCgamma2 was dependent on Btk and Tec. We found accumulation of diacylglycerol (DAG), a PLCgamma product, in phagosome membranes, and activated Btk, but not Tec, colocalized with phagosomal DAG. Inhibition of Tec family kinase activity increased the level of DAG in phagosomes, suggesting a negative regulatory role for Btk. Tec, in contrast, clustered at sites near phagosome formation. In summary, we elucidated that Tec family kinases participate in at least two stages of FcgammaR-mediated phagocytosis: activation of Mac-1 during ingestion, and after phagosome formation, during which Btk and Tec potentially have distinct roles.

  1. Molecular mechanism of strict substrate specificity of an extradiol dioxygenase, DesB, derived from Sphingobium sp. SYK-6.

    Directory of Open Access Journals (Sweden)

    Keisuke Sugimoto

    Full Text Available DesB, which is derived from Sphingobium sp. SYK-6, is a type II extradiol dioxygenase that catalyzes a ring opening reaction of gallate. While typical extradiol dioxygenases show broad substrate specificity, DesB has strict substrate specificity for gallate. The substrate specificity of DesB seems to be required for the efficient growth of S. sp. SYK-6 using lignin-derived aromatic compounds. Since direct coordination of hydroxyl groups of the substrate to the non-heme iron in the active site is a critical step for the catalytic reaction of the extradiol dioxygenases, the mechanism of the substrate recognition and coordination of DesB was analyzed by biochemical and crystallographic methods. Our study demonstrated that the direct coordination between the non-heme iron and hydroxyl groups of the substrate requires a large shift of the Fe (II ion in the active site. Mutational analysis revealed that His124 and His192 in the active site are essential to the catalytic reaction of DesB. His124, which interacts with OH (4 of the bound gallate, seems to contribute to proper positioning of the substrate in the active site. His192, which is located close to OH (3 of the gallate, is likely to serve as the catalytic base. Glu377' interacts with OH (5 of the gallate and seems to play a critical role in the substrate specificity. Our biochemical and structural study showed the substrate recognition and catalytic mechanisms of DesB.

  2. Dectin-1-Syk-CARD9 Signaling Pathway in TB Immunity.

    Science.gov (United States)

    Wagener, Matthew; Hoving, J Claire; Ndlovu, Hlumani; Marakalala, Mohlopheni J

    2018-01-01

    One of the first steps toward mounting an effective immune response to Mycobacterium tuberculosis (Mtb) is recognition of the pathogen through pattern-recognition receptors (PRRs) expressed by innate immune cells. Activation of the PRR Dectin-1 by an unknown mycobacterial ligand triggers an intracellular signaling cascade involving numerous proteins, including spleen tyrosine kinase, protein kinase C-delta, and caspase recruitment domain family member 9, some of which have been shown to influence host immune response to TB infection. Here, we review the role of Dectin-1 signaling pathway in anti-mycobacterial immunity and discuss its contribution in the control of Mtb infection, and potential applications in TB vaccine adjuvanticity.

  3. Kinases and Cancer.

    Science.gov (United States)

    Cicenas, Jonas; Zalyte, Egle; Bairoch, Amos; Gaudet, Pascale

    2018-03-01

    Protein kinases are a large family of enzymes catalyzing protein phosphorylation. The human genome contains 518 protein kinase genes, 478 of which belong to the classical protein kinase family and 40 are atypical protein kinases [...].

  4. Kinases and Cancer

    OpenAIRE

    Jonas Cicenas; Egle Zalyte; Amos Bairoch; Pascale Gaudet

    2018-01-01

    Protein kinases are a large family of enzymes catalyzing protein phosphorylation. The human genome contains 518 protein kinase genes, 478 of which belong to the classical protein kinase family and 40 are atypical protein kinases [...

  5. El rol de las proteínas tirosina quinasas ZAP-70 y Syk en la activación de las células T: Estudios preclínicos de terapia génica para la deficiencia en ZAP-70

    OpenAIRE

    Steinberg, Marcos Wenceslao

    2003-01-01

    Las proteínas ZAP-70 y Syk componen la familia Syk de tirosina quinasas. Estas dos proteínas presentan secuencias de amino ácidos y estructuras similares, sin embargo ZAP-70 y Syk son reguladas diferentemente en términos de expresión y probablemente de función. En los linfocitos T, estas quinasas intervienen en la diferenciación y la activación celular mediada por el receptor de células T (TCR). En este trabajo hemos sido capaces de realizar un estudio comparativo del rol de ZAP-70 y de Syk e...

  6. Dectin-1-Syk-CARD9 Signaling Pathway in TB Immunity

    Directory of Open Access Journals (Sweden)

    Matthew Wagener

    2018-02-01

    Full Text Available One of the first steps toward mounting an effective immune response to Mycobacterium tuberculosis (Mtb is recognition of the pathogen through pattern-recognition receptors (PRRs expressed by innate immune cells. Activation of the PRR Dectin-1 by an unknown mycobacterial ligand triggers an intracellular signaling cascade involving numerous proteins, including spleen tyrosine kinase, protein kinase C-delta, and caspase recruitment domain family member 9, some of which have been shown to influence host immune response to TB infection. Here, we review the role of Dectin-1 signaling pathway in anti-mycobacterial immunity and discuss its contribution in the control of Mtb infection, and potential applications in TB vaccine adjuvanticity.

  7. Cloning and Sequencing of Protein Kinase cDNA from Harbor Seal (Phoca vitulina Lymphocytes

    Directory of Open Access Journals (Sweden)

    Jennifer C. C. Neale

    2004-01-01

    Full Text Available Protein kinases (PKs play critical roles in signal transduction and activation of lymphocytes. The identification of PK genes provides a tool for understanding mechanisms of immunotoxic xenobiotics. As part of a larger study investigating persistent organic pollutants in the harbor seal and their possible immunomodulatory actions, we sequenced harbor seal cDNA fragments encoding PKs. The procedure, using degenerate primers based on conserved motifs of human protein tyrosine kinases (PTKs, successfully amplified nine phocid PK gene fragments with high homology to human and rodent orthologs. We identified eight PTKs and one dual (serine/threonine and tyrosine kinase. Among these were several PKs important in early signaling events through the B- and T-cell receptors (FYN, LYN, ITK and SYK and a MAP kinase involved in downstream signal transduction. V-FGR, RET and DDR2 were also expressed. Sequential activation of protein kinases ultimately induces gene transcription leading to the proliferation and differentiation of lymphocytes critical to adaptive immunity. PKs are potential targets of bioactive xenobiotics, including persistent organic pollutants of the marine environment; characterization of these molecules in the harbor seal provides a foundation for further research illuminating mechanisms of action of contaminants speculated to contribute to large-scale die-offs of marine mammals via immunosuppression.

  8. An indoxyl compound 5-bromo-4-chloro-3-indolyl 1,3-diacetate, CAC-0982, suppresses activation of Fyn kinase in mast cells and IgE-mediated allergic responses in mice

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jun Ho [Department of Immunology, School of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); College of Medicine, Korea University, Seoul 136-701 (Korea, Republic of); Kim, Tae Hyung [College of Pharmacy, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Hyuk Soon; Kim, A-Ram [Department of Immunology, School of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); Kim, Do-Kyun [Department of Immunology, School of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD (United States); Nam, Seung Taek; Kim, Hyun Woo; Park, Young Hwan; Her, Erk; Park, Yeong Min [Department of Immunology, School of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of); Kim, Hyung Sik [College of Pharmacy, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Young Mi [College of Pharmacy, Duksung Women' s University, Seoul 132-714 (Korea, Republic of); Choi, Wahn Soo, E-mail: wahnchoi@kku.ac.kr [Department of Immunology, School of Medicine, Konkuk University, Chungju 380-701 (Korea, Republic of)

    2015-06-15

    Mast cells, constituents of virtually all organs and tissues, are critical cells in IgE-mediated allergic responses. The aim of this study was to investigate the effect and mechanism of an indoxyl chromogenic compound, 5-bromo-4-chloro-3-indolyl 1,3-diacetate, CAC-0982, on IgE-mediated mast cell activation and allergic responses in mice. CAC-0982 reversibly suppressed antigen-stimulated degranulation in murine mast cells (IC{sub 50}, ~ 3.8 μM) and human mast cells (IC{sub 50}, ~ 3.0 μM). CAC-0982 also inhibited the expression and secretion of IL-4 and TNF-α in mast cells. Furthermore, CAC-0982 suppressed the mast cell-mediated allergic responses in mice in a dose-dependent manner (ED{sub 50} 27.9 mg/kg). As for the mechanism, CAC-0982 largely suppressed the phosphorylation of Syk and its downstream signaling molecules, including LAT, Akt, Erk1/2, p38, and JNK. Notably, the tyrosine kinase assay of antigen-stimulated mast cells showed that CAC-0982 inhibited Fyn kinase, one of the upstream tyrosine kinases for Syk activation in mast cells. Taken together, these results suggest that CAC-0982 may be used as a new treatment for regulating IgE-mediated allergic diseases through the inhibition of the Fyn/Syk pathway in mast cells. - Highlights: • The anti-allergic effect of 5-bromo-4-chloro-3-indolyl 1,3-diacetate, CAC-0982, was measured. • CAC-0982 reversibly suppressed the activation of mast cells by IgE and antigen. • CAC-0982 inhibited passive cutaneous anaphylaxis in mice. • CAC-0982 suppresses mast cells through inhibition of Fyn activation in mast cells.

  9. Phenolic constituents isolated from Fragaria ananassa Duch. inhibit antigen-stimulated degranulation through direct inhibition of spleen tyrosine kinase activation.

    Science.gov (United States)

    Ninomiya, Masayuki; Itoh, Tomohiro; Ishikawa, Suguru; Saiki, Miho; Narumiya, Kenji; Yasuda, Masaharu; Koshikawa, Kaneyuki; Nozawa, Yoshinori; Koketsu, Mamoru

    2010-08-15

    We isolated eight phenolic constituents from Fragaria ananassa Duch. (strawberry) and determined their structures using 1D, 2D-NMR. Among the isolated compounds, linocinnamarin (LN), 1-O-trans-cinnamoyl-beta-d-glucopyranose (CG), and cinnamic acid (CA) exhibited antigen (Ag)-stimulated degranulation in rat basophilic leukemia RBL-2H3 cells. In order to reveal the underlying mechanisms, we examined the effects of LN and CA on cellular responses induced by antigen stimulation. Treatment with both LN and CA markedly inhibited antigen-stimulated elevation of intracellular free Ca(2+) concentration and reactive oxygen species (ROS). Both LN and CA suppressed Ag-stimulated spleen tyrosine kinase (Syk) activation. These results indicate that inhibition of antigen-stimulated degranulation by LN and CA is mainly due to inactivation of Syk/phospholipase Cgamma (PLCgamma) pathways. Our findings suggest that LN and CA isolated from F. ananassa Duch. (strawberry) could be beneficial agents for alleviating symptoms of type I allergy. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. Nuclear localization of Src-family tyrosine kinases is required for growth factor-induced euchromatinization

    International Nuclear Information System (INIS)

    Takahashi, Akinori; Obata, Yuuki; Fukumoto, Yasunori; Nakayama, Yuji; Kasahara, Kousuke; Kuga, Takahisa; Higashiyama, Yukihiro; Saito, Takashi; Yokoyama, Kazunari K.; Yamaguchi, Naoto

    2009-01-01

    Src-family kinases (SFKs), which participate in various signaling events, are found at not only the plasma membrane but also several subcellular compartments, including the nucleus. Nuclear structural changes are frequently observed during transcription, cell differentiation, senescence, tumorigenesis, and cell cycle. However, little is known about signal transduction in the alteration of chromatin texture. Here, we develop a pixel imaging method for quantitatively evaluating chromatin structural changes. Growth factor stimulation increases euchromatic hypocondensation and concomitant heterochromatic hypercondensation in G 1 phase, and the levels reach a plateau by 30 min, sustain for at least 5 h and return to the basal levels after 24 h. Serum-activated SFKs in the nucleus were more frequently detected in the euchromatin areas than the heterochromatin areas. Nuclear expression of kinase-active SFKs, but not unrelated Syk kinase, drastically increases both euchromatinization and heterochromatinization in a manner dependent on the levels of nuclear tyrosine phosphorylation. However, growth factor stimulation does not induce chromatin structural changes in SYF cells lacking SFKs, and reintroduction of one SFK member into SYF cells can, albeit insufficiently, induce chromatin structural changes. These results suggest that nuclear tyrosine phosphorylation by SFKs plays an important role in chromatin structural changes upon growth factor stimulation.

  11. Methanol extract of Hopea odorata suppresses inflammatory responses via the direct inhibition of multiple kinases.

    Science.gov (United States)

    Yang, Yanyan; Yu, Tao; Lee, Yong Gyu; Yang, Woo Seok; Oh, Jueun; Jeong, Deok; Lee, Sukchan; Kim, Tae Woong; Park, Yung Chul; Sung, Gi-Ho; Cho, Jae Youl

    2013-01-30

    Hopea odorata Roxb. (Dipterocarpaceae) is a representative Thai ethnopharmacological herbal plant used in the treatment of various inflammation-related diseases. In spite of its traditional use, systematic studies of its anti-inflammatory action have not been performed. The inhibitory activities of a Hopea odorata methanol extract (Ho-ME) on the production of nitric oxide (NO), tumour necrosis factor (TNF)-α, and prostaglandin E(2) (PGE(2)) in RAW264.7 cells and peritoneal macrophages were investigated. The effects of Ho-ME on the gastritis symptoms induced by HCl/EtOH and on ear oedemas induced by arachidonic acid were also examined. Furthermore, to identify the immunopharmacological targets of this extract, nuclear fractionation, a reporter gene assay, immunoprecipitation, immunoblot analysis, and a kinase assay were employed. Ho-ME strongly inhibited the release of NO, PGE(2), and TNF-α in RAW264.7 cells and peritoneal macrophages stimulated by lipopolysaccharide (LPS). Ho-ME also clearly suppressed the gene expression of pro-inflammatory cytokines and chemokines, such as interferon (IFN)-β, interleukin (IL)-12, and monocyte chemotactic protein-1 (MCP-1). By analysing the inhibited target molecules, Syk and Src were found to be suppressed in the inhibition of nuclear factor (NF)-κB pathway. In addition, the observed downregulation of activator protein (AP)-1 and cAMP response element-binding (CREB) was due to the direct inhibition of interleukin-1 receptor-associated kinase (IRAK)1 and IRAK4, which was also linked to the suppression of c-Jun N-terminal kinase (JNK) and p38. In agreement with the in vitro observations, this extract also ameliorated the inflammatory symptoms in EtOH/HCl-induced gastritis and arachidonic acid-induced ear oedemas in mice. Ho-ME has potential as a functional herbal remedy targeting Syk- and Src-mediated anti-inflammatory mechanisms. Future pre-clinical studies will be needed to investigate this possibility. Copyright © 2012

  12. Tyrosol Suppresses Allergic Inflammation by Inhibiting the Activation of Phosphoinositide 3-Kinase in Mast Cells.

    Directory of Open Access Journals (Sweden)

    In-Gyu Je

    Full Text Available Allergic diseases such as atopic dermatitis, rhinitis, asthma, and anaphylaxis are attractive research areas. Tyrosol (2-(4-hydroxyphenylethanol is a polyphenolic compound with diverse biological activities. In this study, we investigated whether tyrosol has anti-allergic inflammatory effects. Ovalbumin-induced active systemic anaphylaxis and immunoglobulin E-mediated passive cutaneous anaphylaxis models were used for the immediate-type allergic responses. Oral administration of tyrosol reduced the allergic symptoms of hypothermia and pigmentation in both animal models. Mast cells that secrete allergic mediators are key regulators on allergic inflammation. Tyrosol dose-dependently decreased mast cell degranulation and expression of inflammatory cytokines. Intracellular calcium levels and activation of inhibitor of κB kinase (IKK regulate cytokine expression and degranulation. Tyrosol blocked calcium influx and phosphorylation of the IKK complex. To define the molecular target for tyrosol, various signaling proteins involved in mast cell activation such as Lyn, Syk, phosphoinositide 3-kinase (PI3K, and Akt were examined. Our results showed that PI3K could be a molecular target for tyrosol in mast cells. Taken together, these findings indicated that tyrosol has anti-allergic inflammatory effects by inhibiting the degranulation of mast cells and expression of inflammatory cytokines; these effects are mediated via PI3K. Therefore, we expect tyrosol become a potential therapeutic candidate for allergic inflammatory disorders.

  13. Applying ligands profiling using multiple extended electron distribution based field templates and feature trees similarity searching in the discovery of new generation of urea-based antineoplastic kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Eman M Dokla

    Full Text Available This study provides a comprehensive computational procedure for the discovery of novel urea-based antineoplastic kinase inhibitors while focusing on diversification of both chemotype and selectivity pattern. It presents a systematic structural analysis of the different binding motifs of urea-based kinase inhibitors and the corresponding configurations of the kinase enzymes. The computational model depends on simultaneous application of two protocols. The first protocol applies multiple consecutive validated virtual screening filters including SMARTS, support vector-machine model (ROC = 0.98, Bayesian model (ROC = 0.86 and structure-based pharmacophore filters based on urea-based kinase inhibitors complexes retrieved from literature. This is followed by hits profiling against different extended electron distribution (XED based field templates representing different kinase targets. The second protocol enables cancericidal activity verification by using the algorithm of feature trees (Ftrees similarity searching against NCI database. Being a proof-of-concept study, this combined procedure was experimentally validated by its utilization in developing a novel series of urea-based derivatives of strong anticancer activity. This new series is based on 3-benzylbenzo[d]thiazol-2(3H-one scaffold which has interesting chemical feasibility and wide diversification capability. Antineoplastic activity of this series was assayed in vitro against NCI 60 tumor-cell lines showing very strong inhibition of GI(50 as low as 0.9 uM. Additionally, its mechanism was unleashed using KINEX™ protein kinase microarray-based small molecule inhibitor profiling platform and cell cycle analysis showing a peculiar selectivity pattern against Zap70, c-src, Mink1, csk and MeKK2 kinases. Interestingly, it showed activity on syk kinase confirming the recent studies finding of the high activity of diphenyl urea containing compounds against this kinase. Allover, the new series

  14. Muscle phosphorylase kinase deficiency

    DEFF Research Database (Denmark)

    Preisler, N; Orngreen, M C; Echaniz-Laguna, A

    2012-01-01

    To examine metabolism during exercise in 2 patients with muscle phosphorylase kinase (PHK) deficiency and to further define the phenotype of this rare glycogen storage disease (GSD).......To examine metabolism during exercise in 2 patients with muscle phosphorylase kinase (PHK) deficiency and to further define the phenotype of this rare glycogen storage disease (GSD)....

  15. Pyruvate kinase blood test

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003357.htm Pyruvate kinase blood test To use the sharing features on this page, ... energy when oxygen levels are low. How the Test is Performed A blood sample is needed. In the laboratory, white blood ...

  16. Phosphatidylinositol 3'-kinase and tyrosine-phosphatase activation positively modulate Convulxin-induced platelet activation. Comparison with collagen.

    Science.gov (United States)

    Lagrue, A H; Francischetti, I M; Guimarães, J A; Jandrot-Perrus, M

    1999-04-01

    In this report we have studied the role of phosphatidylinositol 3'-kinase (PI3-K) and tyrosine phosphatase activation on platelet activation by Convulxin (Cvx). Wortmannin, a specific PI3-K inhibitor, and phenylarsine oxide (PAO), a sulfhydryl reagent that inhibits tyrosine phosphatase (PTPase), block Cvx-induced platelet aggregation, granule secretion, inositol phosphate production, and increase in [Ca2+]i. However, PAO does not inhibit Cvx-induced tyrosine phosphorylation of platelet proteins, including Syk and PLCgamma2, but blocked collagen-induced platelet aggregation as well as tyrosine phosphorylation of PLCgamma2. In contrast, Cvx-induced PLCgamma2 tyrosyl phosphorylation was partially inhibited by wortmannin. We conclude that (i) although Cvx and collagen activate platelets by a similar mechanism, different regulatory processes are specific to each agonist; (ii) mechanisms other than tyrosine phosphorylation regulate PLCgamma2 activity; and (iii) besides protein tyrosine kinases, PI3-K (and PTPase) positively modulate platelet activation by both Cvx and collagen, and this enzyme is required for effective transmission of GPVI-Fc receptor gamma chain signal to result in full activation and tyrosine phosphorylation of PLCgamma2 in Cvx-stimulated platelets.

  17. Tyrosine kinases in rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Kobayashi Akiko

    2011-08-01

    Full Text Available Abstract Rheumatoid arthritis (RA is an inflammatory, polyarticular joint disease. A number of cellular responses are involved in the pathogenesis of rheumatoid arthritis, including activation of inflammatory cells and cytokine expression. The cellular responses involved in each of these processes depends on the specific signaling pathways that are activated; many of which include protein tyrosine kinases. These pathways include the mitogen-activated protein kinase pathway, Janus kinases/signal transducers and activators transcription pathway, spleen tyrosine kinase signaling, and the nuclear factor κ-light-chain-enhancer of activated B cells pathway. Many drugs are in development to target tyrosine kinases for the treatment of RA. Based on the number of recently published studies, this manuscript reviews the role of tyrosine kinases in the pathogenesis of RA and the potential role of kinase inhibitors as new therapeutic strategies of RA.

  18. Regulation of Autophagy by Kinases

    International Nuclear Information System (INIS)

    Sridharan, Savitha; Jain, Kirti; Basu, Alakananda

    2011-01-01

    Autophagy is a process of self-degradation that maintains cellular viability during periods of metabolic stress. Although autophagy is considered a survival mechanism when faced with cellular stress, extensive autophagy can also lead to cell death. Aberrations in autophagy are associated with several diseases, including cancer. Therapeutic exploitation of this process requires a clear understanding of its regulation. Although the core molecular components involved in the execution of autophagy are well studied there is limited information on how cellular signaling pathways, particularly kinases, regulate this complex process. Protein kinases are integral to the autophagy process. Atg1, the first autophagy-related protein identified, is a serine/threonine kinase and it is regulated by another serine/threonine kinase mTOR. Emerging studies suggest the participation of many different kinases in regulating various components/steps of this catabolic process. This review focuses on the regulation of autophagy by several kinases with particular emphasis on serine/threonine protein kinases such as mTOR, AMP-activated protein kinase, Akt, mitogen-activated protein kinase (ERK, p38 and JNK) and protein kinase C that are often deregulated in cancer and are important therapeutic targets

  19. Regulation of Autophagy by Kinases

    Energy Technology Data Exchange (ETDEWEB)

    Sridharan, Savitha; Jain, Kirti; Basu, Alakananda, E-mail: alakananda.basu@unthsc.edu [Department of Molecular Biology and Immunology, Institute for Cancer Research, University of North Texas Health Science Center, Fort Worth, TX 76107 (United States)

    2011-06-09

    Autophagy is a process of self-degradation that maintains cellular viability during periods of metabolic stress. Although autophagy is considered a survival mechanism when faced with cellular stress, extensive autophagy can also lead to cell death. Aberrations in autophagy are associated with several diseases, including cancer. Therapeutic exploitation of this process requires a clear understanding of its regulation. Although the core molecular components involved in the execution of autophagy are well studied there is limited information on how cellular signaling pathways, particularly kinases, regulate this complex process. Protein kinases are integral to the autophagy process. Atg1, the first autophagy-related protein identified, is a serine/threonine kinase and it is regulated by another serine/threonine kinase mTOR. Emerging studies suggest the participation of many different kinases in regulating various components/steps of this catabolic process. This review focuses on the regulation of autophagy by several kinases with particular emphasis on serine/threonine protein kinases such as mTOR, AMP-activated protein kinase, Akt, mitogen-activated protein kinase (ERK, p38 and JNK) and protein kinase C that are often deregulated in cancer and are important therapeutic targets.

  20. Regulation of Autophagy by Kinases

    Science.gov (United States)

    Sridharan, Savitha; Jain, Kirti; Basu, Alakananda

    2011-01-01

    Autophagy is a process of self-degradation that maintains cellular viability during periods of metabolic stress. Although autophagy is considered a survival mechanism when faced with cellular stress, extensive autophagy can also lead to cell death. Aberrations in autophagy are associated with several diseases, including cancer. Therapeutic exploitation of this process requires a clear understanding of its regulation. Although the core molecular components involved in the execution of autophagy are well studied there is limited information on how cellular signaling pathways, particularly kinases, regulate this complex process. Protein kinases are integral to the autophagy process. Atg1, the first autophagy-related protein identified, is a serine/threonine kinase and it is regulated by another serine/threonine kinase mTOR. Emerging studies suggest the participation of many different kinases in regulating various components/steps of this catabolic process. This review focuses on the regulation of autophagy by several kinases with particular emphasis on serine/threonine protein kinases such as mTOR, AMP-activated protein kinase, Akt, mitogen-activated protein kinase (ERK, p38 and JNK) and protein kinase C that are often deregulated in cancer and are important therapeutic targets. PMID:24212825

  1. Regulation of Autophagy by Kinases

    Directory of Open Access Journals (Sweden)

    Savitha Sridharan

    2011-06-01

    Full Text Available Autophagy is a process of self-degradation that maintains cellular viability during periods of metabolic stress. Although autophagy is considered a survival mechanism when faced with cellular stress, extensive autophagy can also lead to cell death. Aberrations in autophagy are associated with several diseases, including cancer. Therapeutic exploitation of this process requires a clear understanding of its regulation. Although the core molecular components involved in the execution of autophagy are well studied there is limited information on how cellular signaling pathways, particularly kinases, regulate this complex process. Protein kinases are integral to the autophagy process. Atg1, the first autophagy-related protein identified, is a serine/threonine kinase and it is regulated by another serine/threonine kinase mTOR. Emerging studies suggest the participation of many different kinases in regulating various components/steps of this catabolic process. This review focuses on the regulation of autophagy by several kinases with particular emphasis on serine/threonine protein kinases such as mTOR, AMP-activated kinase, Akt, mitogen-activated protein kinase (ERK, p38 and JNK and protein kinase C that are often deregulated in cancer and are important therapeutic targets.

  2. Anomalous constitutive Src kinase activity promotes B lymphoma survival and growth

    Directory of Open Access Journals (Sweden)

    Robertson Darrell A

    2009-12-01

    Full Text Available Abstract Background Previously we have shown that B cell receptor (BCR expression and B cell receptor signaling pathways are important for the basal growth of B lymphoma cells. In particular we have shown that the activation of Syk, a non-src family protein tyrosine kinase and the mitogen activated protein kinases (MAPK, ERK and JNK that mediate BCR signals are required for the constitutive growth of B lymphoma cells. Since src family protein tyrosine kinases (SFKs like Lyn are known to be needed for the phosphorylation of BCR co-receptors, Ig-α and Ig-β, we hypothesized that one or more SFKs will be constitutively activated in B lymphoma cells and may be necessary for B lymphoma growth. Results Src kinase activity was found to be constitutively high in many murine and human B lymphoma cell lines and primary lymphoma samples. The specific pharmacological inhibitors of SFKs, PP1 and PP2 inhibited the proliferation of a number of both murine and human B lymphomas in a dose-dependent manner. Importantly, dasatinib (BMS-354825, an oral dual BCR-ABL and SFK specific inhibitor inhibited the growth of B lymphomas in the nanomolar range in vitro and strongly inhibited a mouse lymphoma growth in vivo. Among the SFKs, Lyn is predominantly phosphorylated and Lyn-specific small interfering RNA inhibited the growth of B lymphomas, supporting an important role for Lyn in B lymphoma growth. Suppression of SFK activity blocks BCR mediated signaling pathways. PMA or CpG can partially reverse the growth inhibition induced by SFK inhibition. Although blocking SFK activity inhibited the growth of a number of B lymphomas, some lymphomas such as SudHL-4, SudHL-6, OCI-Ly3 and OCI-Ly10 are more resistant due to an increased expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL. Conclusions These studies further support our concept that BCR signaling pathways are important for the continued growth of established B lymphoma cells. Some of the intermediates in this

  3. Role of focal adhesion tyrosine kinases in GPVI-dependent platelet activation and reactive oxygen species formation.

    Directory of Open Access Journals (Sweden)

    Naadiya Carrim

    Full Text Available We have previously shown the presence of a TRAF4/p47phox/Hic5/Pyk2 complex associated with the platelet collagen receptor, GPVI, consistent with a potential role of this complex in GPVI-dependent ROS formation. In other cell systems, NOX-dependent ROS formation is facilitated by Pyk2, which along with its closely related homologue FAK are known to be activated and phosphorylated downstream of ligand binding to GPVI.To evaluate the relative roles of Pyk2 and FAK in GPVI-dependent ROS formation and to determine their location within the GPVI signaling pathway.Human and mouse washed platelets (from WT or Pyk2 KO mice were pre-treated with pharmacological inhibitors targeting FAK or Pyk2 (PF-228 and Tyrphostin A9, respectively and stimulated with the GPVI-specific agonist, CRP. FAK, but not Pyk2, was found to be essential for GPVI-dependent ROS production and aggregation. Subsequent human platelet studies with PF-228 confirmed FAK is essential for GPVI-mediated phosphatidylserine exposure, α-granule secretion (P-selectin (CD62P surface expression and integrin αIIbβ3 activation. To determine the precise location of FAK within the GPVI pathway, we analyzed the effect of PF-228 inhibition in CRP-stimulated platelets in conjunction with immunoprecipitation and pulldown analysis to show that FAK is downstream of Lyn, Spleen tyrosine kinase (Syk, PI3-K and Bruton's tyrosine kinase (Btk and upstream of Rac1, PLCγ2, Ca2+ release, PKC, Hic-5, NOX1 and αIIbβ3 activation.Overall, these data suggest a novel role for FAK in GPVI-dependent ROS formation and platelet activation and elucidate a proximal signaling role for FAK within the GPVI pathway.

  4. Protein kinase CK2 in human diseases

    DEFF Research Database (Denmark)

    Guerra, Barbara; Issinger, Olaf-Georg

    2008-01-01

    . The catalytic alpha subunits are distantly related to the CMGC subfamily of kinases, such as the Cdk kinases. There are some peculiarities associated with protein kinase CK2, which are not found with most other protein kinases: (i) the enzyme is constitutively active, (ii) it can use ATP and GTP and (iii...

  5. Citron kinase - renaissance of a neglected mitotic kinase.

    Science.gov (United States)

    D'Avino, Pier Paolo

    2017-05-15

    Cell division controls the faithful segregation of genomic and cytoplasmic materials between the two nascent daughter cells. Members of the Aurora, Polo and cyclin-dependent (Cdk) kinase families are known to regulate multiple events throughout cell division, whereas another kinase, citron kinase (CIT-K), for a long time has been considered to function solely during cytokinesis, the last phase of cell division. CIT-K was originally proposed to regulate the ingression of the cleavage furrow that forms at the equatorial cortex of the dividing cell after chromosome segregation. However, studies in the last decade have clarified that this kinase is, instead, required for the organization of the midbody in late cytokinesis, and also revealed novel functions of CIT-K earlier in mitosis and in DNA damage control. Moreover, CIT-K mutations have recently been linked to the development of human microcephaly, and CIT-K has been identified as a potential target in cancer therapy. In this Commentary, I describe and re-evaluate the functions and regulation of CIT-K during cell division and its involvement in human disease. Finally, I offer my perspectives on the open questions and future challenges that are necessary to address, in order to fully understand this important and yet unjustly neglected mitotic kinase. © 2017. Published by The Company of Biologists Ltd.

  6. Epstein-Barr Virus Latent Membrane Protein 2A (LMP2A) enhances IL-10 production through the activation of Bruton's tyrosine kinase and STAT3.

    Science.gov (United States)

    Incrocci, Ryan; Barse, Levi; Stone, Amanda; Vagvala, Sai; Montesano, Michael; Subramaniam, Vijay; Swanson-Mungerson, Michelle

    2017-01-01

    Previous data demonstrate that Epstein-Barr Virus Latent Membrane Protein 2A (LMP2A) enhances IL-10 to promote the survival of LMP2A-expressing B cell lymphomas. Since STAT3 is an important regulator of IL-10 production, we hypothesized that LMP2A activates a signal transduction cascade that increases STAT3 phosphorylation to enhance IL-10. Using LMP2A-negative and -positive B cell lines, the data indicate that LMP2A requires the early signaling molecules of the Syk/RAS/PI3K pathway to increase IL-10. Additional studies indicate that the PI3K-regulated kinase, BTK, is responsible for phosphorylating STAT3, which ultimately mediates the LMP2A-dependent increase in IL-10. These data are the first to show that LMP2A signaling results in STAT3 phosphorylation in B cells through a PI3K/BTK-dependent pathway. With the use of BTK and STAT3 inhibitors to treat B cell lymphomas in clinical trials, these findings highlight the possibility of using new pharmaceutical approaches to treat EBV-associated lymphomas that express LMP2A. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Chitin and stress induced protein kinase activation

    DEFF Research Database (Denmark)

    Kenchappa, Chandra Shekar; Azevedo da Silva, Raquel; Bressendorff, Simon

    2017-01-01

    The assays described here are pertinent to protein kinase studies in any plant. They include an immunoblot phosphorylation/activation assay and an in-gel activity assay for MAP kinases (MPKs) using the general protein kinase substrate myelin basic protein. They also include a novel in-gel peptide...... substrate assay for Snf1-related kinase family 2 members (SnRK2s). This kinase family-specific assay overcomes some limitations of in-gel assays and permits the identification of different types of kinase activities in total protein extracts....

  8. Bacterial Protein-Tyrosine Kinases

    DEFF Research Database (Denmark)

    Shi, Lei; Kobir, Ahasanul; Jers, Carsten

    2010-01-01

    phosphorylation. Protein-tyrosine phosphorylation in bacteria is particular with respect to very low occupancy of phosphorylation sites in vivo; this has represented a major challenge for detection techniques. Only the recent breakthroughs in gel-free high resolution mass spectrometry allowed the systematic...... detection of phosphorylated tyrosines by phosphoprotomics studies in bacteria. Other pioneering studies conducted in recent years, such as the first structures of BY-kinases and biochemical and phyiological studies of new BY-kinase substrates significantly furthered our understanding of these enzymes...

  9. Association study of genetic variants in PLA2G4A, PLCG1, LAT, SYK, and TNFRS11A genes in NSAIDs-induced urticaria and/or angioedema patients.

    Science.gov (United States)

    Ayuso, Pedro; Plaza-Serón, María del Carmen; Doña, Inmaculada; Blanca-López, Natalia; Campo, Paloma; Cornejo-García, José A; Perkins, James R; Torres, Maria J; Blanca, Miguel; Canto, Gabriela

    2015-12-01

    NSAIDs-induced urticaria and/or angioedema (NIUA) is the most frequent entity of hypersensitivity reactions to NSAIDs. The underlying cause is considered to be because of a nonspecific immunological mechanism in which mast cells are key players. We studied the association of nine single nucleotide polymorphisms in five genes involved in mast cell activation (SYK, LAT1, PLCG1, PLA2G4A, and TNFRSF11A) in 450 NIUA patients and 500 controls. We identified several statistically significant associations when stratifying patients by symptoms: PLA2G4A rs12746200 (urticaria vs. controls, Pc=0.005). PLCG1 rs2228246 (angioedema vs. controls; Pc=0.044), and TNFRS11A rs1805034 (urticaria+angioedema vs. controls; Pc=0.041). The frequency of haplotype PLCG1 rs753381-rs2228246 (C-G) in angioedema-NIUA patients was lower than that in controls (Pc=0.040). In addition, the haplotype frequency of TNFRS11A rs1805034-rs35211496 (C-T) was higher among urticaria-NIUA and urticaria+angioedema-NIUA patients than the controls (Pc=0.045 and 0.046). Our results shed light on the involvement of variants in genes related to non-immunological mast cell activation in NIUA.

  10. Glycogen Synthase Kinase-3β

    DEFF Research Database (Denmark)

    Munkholm, Klaus; Lenskjold, Toke; Jacoby, Anne Sophie

    2016-01-01

    Evidence indicates a role for glycogen synthase kinase-3β (GSK-3β) in the pathophysiology of mood disorders and in cognitive disturbances; however, the natural variation in GSK-3β activity over time is unknown. We aimed to investigate GSK-3β activity over time and its possible correlation...

  11. Non-Viral Deoxyribonucleoside Kinases

    DEFF Research Database (Denmark)

    Christiansen, Louise Slot; Munch-Petersen, Birgitte; Knecht, Wolfgang

    2015-01-01

    Deoxyribonucleoside kinases (dNKs) phosphorylate deoxyribonucleosides to their corresponding monophosphate compounds. dNks also phosphorylate deoxyribonucleoside analogues that are used in the treatment of cancer or viral infections. The study of the mammalian dNKs has therefore always been of gr...

  12. The alpha-kinase family: an exceptional branch on the protein kinase tree.

    NARCIS (Netherlands)

    Middelbeek, J.A.J.; Clark, K.; Venselaar, H.; Huynen, M.A.; Leeuwen, F.N. van

    2010-01-01

    The alpha-kinase family represents a class of atypical protein kinases that display little sequence similarity to conventional protein kinases. Early studies on myosin heavy chain kinases in Dictyostelium discoideum revealed their unusual propensity to phosphorylate serine and threonine residues in

  13. Growth factors and kinases in glioblastoma growth

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Peña-Ortiz

    2016-10-01

    Full Text Available Glioblastoma multiforme (GBM is the most aggressive type of brain cancer, having the highest invasion, migration, proliferation, and angiogenesis rates. Several signaling pathways are involved in the regulation of these processes including growth factors and their tyrosine kinase receptors, such as vascular endothelial growth factor (VEGF, transforming growth factor beta (TGFβ, fibroblast growth factor (FGF, platelet-derived growth factor (PDGF, and insulin-like growth factor–I (IGF–I. Different kinases and regulators also participate in signaling pathways initiated by growth factors, such as mitogen-activated kinases (MAPK, protein kinases C (PKC, phosphatidylinositol-3 kinases (PI3K, protein kinase B (PKB or Akt, glycogen synthase kinase 3β (GSK3β, the mTOR complex, and Bcl-2. In this review, we will focus on the role of these proteins as possible therapeutic targets in GBM.

  14. DMPD: Bruton's tyrosine kinase (Btk)-the critical tyrosine kinase in LPS signalling? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15081522 Bruton's tyrosine kinase (Btk)-the critical tyrosine kinase in LPS signall...ruton's tyrosine kinase (Btk)-the critical tyrosine kinase in LPS signalling? PubmedID 15081522 Title Bruton...'s tyrosine kinase (Btk)-the critical tyrosine kinase in LPS signalling? Authors

  15. Thymidine kinase diversity in bacteria

    DEFF Research Database (Denmark)

    Sandrini, Michael; Clausen, A.R.; Munch-Petersen, B.

    2006-01-01

    Thymidine kinases (TKs) appear to be almost ubiquitous and are found in nearly all prokaryotes, eukaryotes, and several viruses. They are the key enzymes in thymidine salvage and activation of several anti-cancer and antiviral drugs. We show that bacterial TKs can be subdivided into 2 groups. The....... The TKs from Gram-positive bacteria are more closely related to the eukaryotic TK1 enzymes than are TKs from Gram-negative bacteria....

  16. Spinach Pyruvate Kinase Isoforms 1

    Science.gov (United States)

    Baysdorfer, Chris; Bassham, James A.

    1984-01-01

    Pyruvate kinase from spinach (Spinacea oleracea L.) leaves consists of two isoforms, separable by blue agarose chromatography. Both isoforms share similar pH profiles and substrate and alternate nucleotide Km values. In addition, both isoforms are inhibited by oxalate and ATP and activated by AMP. The isoforms differ in their response to three key metabolites; citrate, aspartate, and glutamate. The first isoform is similar to previously reported plant pyruvate kinases in its sensitivity to citrate inhibition. The Ki for this inhibition is 1.2 millimolar citrate. The second isoform is not affected by citrate but is regulated by aspartate and glutamate. Aspartate is an activator with a Ka of 0.05 millimolar, and glutamate is an inhibitor with a Ki of 0.68 millimolar. A pyruvate kinase with these properties has not been previously reported. Based on these considerations, we suggest that the activity of the first isoform is regulated by respiratory metabolism. The second isoform, in contrast, may be regulated by the demand for carbon skeletons for use in ammonia assimilation. PMID:16663425

  17. A proteomic approach for comprehensively screening substrates of protein kinases such as Rho-kinase.

    Directory of Open Access Journals (Sweden)

    Mutsuki Amano

    Full Text Available BACKGROUND: Protein kinases are major components of signal transduction pathways in multiple cellular processes. Kinases directly interact with and phosphorylate downstream substrates, thus modulating their functions. Despite the importance of identifying substrates in order to more fully understand the signaling network of respective kinases, efficient methods to search for substrates remain poorly explored. METHODOLOGY/PRINCIPAL FINDINGS: We combined mass spectrometry and affinity column chromatography of the catalytic domain of protein kinases to screen potential substrates. Using the active catalytic fragment of Rho-kinase/ROCK/ROK as the model bait, we obtained about 300 interacting proteins from the rat brain cytosol fraction, which included the proteins previously reported as Rho-kinase substrates. Several novel interacting proteins, including doublecortin, were phosphorylated by Rho-kinase both in vitro and in vivo. CONCLUSIONS/SIGNIFICANCE: This method would enable identification of novel specific substrates for kinases such as Rho-kinase with high sensitivity.

  18. Bioinformatic mining of kinase inhibitors that regulate autophagy through kinase signaling pathways.

    Science.gov (United States)

    Yang, Yang; Ma, Biao; Jin, Ye; Ben, Wei; Zhang, Dandan; Jiang, Keping; Feng, Shujun; Huang, Lu; Zheng, Jianhua

    2014-12-01

    The aim of this study was to predict the kinase inhibitors that may regulate autophagy. A total of 62 kinases were obtained through text mining by importing the keyword 'autophagy' and a 'protein kinase' Excel file to PubMed. Subsequently, 146 kinases were derivated through screening in the PubMed database by importing the 'autophagy‑associated gene' and 'protein kinase' files. Following intersection of the above two methods, 54 candidate autophagy‑associated kinases were obtained. Enrichment analysis indicated that these candidate autophagy‑associated kinases were mainly enriched in pathways such as the calcium, Wnt, HIF‑1 and mTOR signaling pathways. Among the 54 kinases, 24 were identified through text mining to have specific kinase inhibitors that regulate the corresponding functions; a total of 56 kinase inhibitors were found to be involved in the regulation of these 24 kinases. In total, nine of these 56 kinase inhibitors identified had been widely reported in autophagy regulation studies, 23 kinase inhibitors had been seldom reported and 24 had never been reported. Therefore, introducing these kinases into autophagy regulation analysis in subsequent studies may produce important results.

  19. Bruton's tyrosine kinase is essential for hydrogen peroxide-induced calcium signaling.

    Science.gov (United States)

    Qin, S; Chock, P B

    2001-07-10

    Using Btk-deficient DT40 cells and the transfectants expressing wild-type Btk or Btk mutants in either kinase (Arg(525) to Gln), Src homology 2 (SH2, Arg(307) to Ala), or pleckstrin homology (PH, Arg(28) to Cys) domains, we investigated the roles and structure-function relationships of Btk in hydrogen peroxide-induced calcium mobilization. Our genetic evidence showed that Btk deficiency resulted in a significant reduction in hydrogen peroxide-induced calcium response. This impaired calcium signaling is correlated with the complete elimination of IP3 production and the significantly reduced tyrosine phosphorylation of PLCgamma2 in Btk-deficient DT40 cells. All of these defects were fully restored by the expression of wild-type Btk in Btk-deficient DT40 cells. The data from the point mutation study revealed that a defect at any one of the three functional domains would prevent a full recovery of Btk-mediated hydrogen peroxide-induced intracellular calcium mobilization. However, mutation at either the SH2 or PH domain did not affect the hydrogen peroxide-induced activation of Btk. Mutation at the SH2 domain abrogates both IP3 generation and calcium release, while the mutant with the nonfunctional PH domain can partially activate PLCgamma2 and catalyze IP3 production but fails to produce significant calcium mobilization. Thus, these observations suggest that Btk-dependent tyrosine phosphorylation of PLCgamma2 is required but not sufficient for hydrogen peroxide-induced calcium mobilization. Furthermore, hydrogen peroxide stimulates a Syk-, but not Btk-, dependent tyrosine phosphorylation of B cell linker protein BLNK. The overall results, together with those reported earlier [Qin et al. (2000) Proc. Natl. Acad. Sci. U.S.A. 97, 7118], are consistent with the notion that functional SH2 and PH domains are required for Btk to form a complex with PLCgamma2 through BLNK in order to position the Btk, PLCgamma2, and phosphatidylinositol 4,5-bisphosphate in close proximity for

  20. Kinases Involved in Both Autophagy and Mitosis

    Directory of Open Access Journals (Sweden)

    Zhiyuan Li

    2017-08-01

    Full Text Available Both mitosis and autophagy are highly regulated dynamic cellular processes and involve various phosphorylation events catalysed by kinases, which play vital roles in almost all physiological and pathological conditions. Mitosis is a key event during the cell cycle, in which the cell divides into two daughter cells. Autophagy is a process in which the cell digests its own cellular contents. Although autophagy regulation has mainly been studied in asynchronous cells, increasing evidence indicates that autophagy is in fact tightly regulated in mitosis. Here in this review, we will discuss kinases that were originally identified to be involved in only one of either mitosis or autophagy, but were later found to participate in both processes, such as CDKs (cyclin-dependent kinases, Aurora kinases, PLK-1 (polo-like kinase 1, BUB1 (budding uninhibited by benzimidazoles 1, MAPKs (mitogen-activated protein kinases, mTORC1 (mechanistic target of rapamycin complex 1, AMPK (AMP-activated protein kinase, PI3K (phosphoinositide-3 kinase and protein kinase B (AKT. By focusing on kinases involved in both autophagy and mitosis, we will get a more comprehensive understanding about the reciprocal regulation between the two key cellular events, which will also shed light on their related therapeutic investigations.

  1. Stimulation of MAP kinase and S6 kinase by vanadium and selenium in rat adipocytes.

    Science.gov (United States)

    Hei, Y J; Farahbakhshian, S; Chen, X; Battell, M L; McNeill, J H

    1998-01-01

    To explore the mechanism underlying the insulin-mimetic actions of vanadium and selenium we examined their effects on the mitogen activated protein/myelin basic protein kinases (MAPK) and ribosomal S6 protein kinases, which are among the best characterized of the kinases that comprise the phosphorylation cascade in insulin signal transduction. We observed a transient activation of MAPK and S6 kinases by insulin in rat adipocytes, while both sodium selenate and vanadyl sulphate produced prolonged activation of the kinases. Vanadyl sulphate stimulated the activity of MAPK and S6 kinase by as much as 6 fold and 15 fold, respectively. Pretreatment of the cells with genistein did not affect the activation of MAPK by insulin, but partially blocked the effects of sodium selenate and vanadyl sulphate. Genistein did not change the activation of S6 kinase by insulin, but blocked the activation in vanadyl sulphate- and sodium selenate-treated-cells, suggesting that a genistein sensitive tyrosine kinase may be involved in the activation by these two compounds. Rapamycin, a specific inhibitor of the p70s6k isoform of S6 kinase, partially reduced the activation of S6 kinase activity by sodium selenate, indicating a role for this kinase in the overall activity of the S6 kinase in sodium selenate-treated cells. A similar trend was noted in vanadyl sulphate-treated cells. Thus, this study supports the involvement of MAPK and S6 kinases in the insulin-mimetic actions of vanadium and selenium.

  2. Receptor Tyrosine Kinases in Drosophila Development

    Science.gov (United States)

    Sopko, Richelle; Perrimon, Norbert

    2013-01-01

    Tyrosine phosphorylation plays a significant role in a wide range of cellular processes. The Drosophila genome encodes more than 20 receptor tyrosine kinases and extensive studies in the past 20 years have illustrated their diverse roles and complex signaling mechanisms. Although some receptor tyrosine kinases have highly specific functions, others strikingly are used in rather ubiquitous manners. Receptor tyrosine kinases regulate a broad expanse of processes, ranging from cell survival and proliferation to differentiation and patterning. Remarkably, different receptor tyrosine kinases share many of the same effectors and their hierarchical organization is retained in disparate biological contexts. In this comprehensive review, we summarize what is known regarding each receptor tyrosine kinase during Drosophila development. Astonishingly, very little is known for approximately half of all Drosophila receptor tyrosine kinases. PMID:23732470

  3. Conformational snapshots of Tec kinases during signaling.

    Science.gov (United States)

    Joseph, Raji E; Andreotti, Amy H

    2009-03-01

    The control of cellular signaling cascades is of utmost importance in regulating the immune response. Exquisitely precise protein-protein interactions and chemical modification of substrates by enzymatic catalysis are the fundamental components of the signals that alert immune cells to the presence of a foreign antigen. In particular, the phosphorylation events induced by protein kinase activity must be spatially and temporally regulated by specific interactions to maintain a normal and effective immune response. High resolution structures of many protein kinases along with supporting biochemical data are providing significant insight into the intricate regulatory mechanisms responsible for controlling cellular signaling. The Tec family kinases are immunologically important kinases for which regulatory details are beginning to emerge. This review focuses on bringing together structural insights gained over the years to develop an understanding of how domain interactions both within the Tec kinases and between the Tec kinases and other signaling molecules control immune cell function.

  4. Measuring Kinase Activity-A Global Challenge.

    Science.gov (United States)

    Cann, Marissa L; McDonald, Ian M; East, Michael P; Johnson, Gary L; Graves, Lee M

    2017-11-01

    The kinase enzymes within a cell, known collectively as the kinome, play crucial roles in many signaling pathways, including survival, motility, differentiation, stress response, and many more. Aberrant signaling through kinase pathways is often linked to cancer, among other diseases. A major area of scientific research involves understanding the relationships between kinases, their targets, and how the kinome adapts to perturbations of the cellular system. This review will discuss many of the current and developing methods for studying kinase activity, and evaluate their applications, advantages, and disadvantages. J. Cell. Biochem. 118: 3595-3606, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Tec family kinases in inflammation and disease.

    Science.gov (United States)

    Horwood, Nicole J; Urbaniak, Ania M; Danks, Lynett

    2012-04-01

    Over the last decade, the Tec family of nonreceptor tyrosine kinases (Btk, Tec, Bmx, Itk, and Rlk) have been shown to play a key role in inflammation and bone destruction. Bruton's tyrosine kinase (Btk) has been the most widely studied due to the critical role of this kinase in B-cell development and recent evidence showing that blocking Btk signaling is effective in ameliorating lymphoma progression and experimental arthritis. This review will examine the role of TFK in myeloid cell function and the potential of targeting these kinases as a therapeutic intervention in autoimmune disorders such as rheumatoid arthritis.

  6. Overcoming Resistance to Inhibitors of the Akt Protein Kinase by Modulation of the Pim Kinase Pathway

    Science.gov (United States)

    2017-01-01

    prostate cancer patients have abnormalities in the AKT signaling pathway. These abnormalities are driven by mutations in the PTEN and AKT proteins as...AWARD NUMBER: W81XWH-12-1-0560 TITLE: Overcoming Resistance to Inhibitors of the Akt Protein Kinase by Modulation of the Pim Kinase Pathway...2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Overcoming Resistance to Inhibitors of the Akt Protein Kinase by Modulation of the Pim Kinase

  7. Nonreceptor Tyrosine Kinases in Prostate

    Directory of Open Access Journals (Sweden)

    Cancer Yu-Ming Chang

    2007-02-01

    Full Text Available BACKGROUND: Carcinoma of the prostate (CaP is the most commonly diagnosed cancer in men in the United States. Signal transduction molecules such as tyrosine kinases play important roles in CaP. Src, a nonreceptor tyrosine kinase (NRTK and the first proto-oncogene discovered is shown to participate in processes such as cell proliferation and migration in CaP. Underscoring NRTK's and, specifically, Src's importance in cancer is the recent approval by the US Food and Drug Administration of dasatinib, the first commercial Src inhibitor for clinical use in chronic myelogenous leukemia (CML. In this review we will focus on NRTKs and their roles in the biology of CaP. MATERIALS AND METHODS: Publicly available literature from PubMed regarding the topic of members of NRTKs in CaP was searched and reviewed. RESULTS: Src, FAK, JaK1/2, and ETK are involved in processes indispensable to the biology of CaP: cell growth, migration, invasion, angiogenesis, and apoptosis. CONCLUSIONS: Src emerges as a common signaling and regulatory molecule in multiple biological processes in CaP. Src's relative importance in particular stages of CaP, however, required further definition. Continued investigation of NRTKs will increase our understanding of their biological function and potential role as new therapeutic targets.

  8. A multisubstrate deoxyribonucleoside kinase from plants

    DEFF Research Database (Denmark)

    Clausen, Anders R.; Girandon, Lenart; Knecht, Wolfgang

    2008-01-01

    and biochemical properties suggest that this deoxyribonucleoside kinase represents a living fossil resembling the progenitor of the modern animal deoxycytidine, deoxyguanosine and thymidine 2 kinases. The broad substrate specificity makes this enzyme an interesting candidate to be evaluated as a suicide gene...

  9. Kinase activity and specificity assay using synthetic peptides.

    Science.gov (United States)

    Wu, Xu Na; Schulze, Waltraud X

    2015-01-01

    Phosphorylation of substrate proteins by protein kinases can lead to activation or inactivation of signaling pathways or metabolic processes. Precise understanding of activity and specificity of protein kinases are important questions in characterization of kinase functions. Here, we describe a procedure to study kinase activity and specificity using kinase-GFP complexes purified from plant material and synthetic peptides as substrates. Magnetic GFP beads allow purifying receptor-like kinase-GFP complexes from microsomal fractions. Kinase-GFP complexes are then incubated with ATP and the synthetic peptides for kinase reaction. Phosphorylation of substrate peptides is then identified and quantified by mass spectrometry.

  10. Platelet Activation and Thrombus Formation over IgG Immune Complexes Requires Integrin αIIbβ3 and Lyn Kinase.

    Directory of Open Access Journals (Sweden)

    Huiying Zhi

    Full Text Available IgG immune complexes contribute to the etiology and pathogenesis of numerous autoimmune disorders, including heparin-induced thrombocytopenia, systemic lupus erythematosus, rheumatoid- and collagen-induced arthritis, and chronic glomerulonephritis. Patients suffering from immune complex-related disorders are known to be susceptible to platelet-mediated thrombotic events. Though the role of the Fc receptor, FcγRIIa, in initiating platelet activation is well understood, the role of the major platelet adhesion receptor, integrin αIIbβ3, in amplifying platelet activation and mediating adhesion and aggregation downstream of encountering IgG immune complexes is poorly understood. The goal of this investigation was to gain a better understanding of the relative roles of these two receptor systems in immune complex-mediated thrombotic complications. Human platelets, and mouse platelets genetically engineered to differentially express FcγRIIa and αIIbβ3, were allowed to interact with IgG-coated surfaces under both static and flow conditions, and their ability to spread and form thrombi evaluated in the presence and absence of clinically-used fibrinogen receptor antagonists. Although binding of IgG immune complexes to FcγRIIa was sufficient for platelet adhesion and initial signal transduction events, platelet spreading and thrombus formation over IgG-coated surfaces showed an absolute requirement for αIIbβ3 and its ligands. Tyrosine kinases Lyn and Syk were found to play key roles in IgG-induced platelet activation events. Taken together, our data suggest a complex functional interplay between FcγRIIa, Lyn, and αIIbβ3 in immune complex-induced platelet activation. Future studies may be warranted to determine whether patients suffering from immune complex disorders might benefit from treatment with anti-αIIbβ3-directed therapeutics.

  11. Mitotic regulation by NIMA-related kinases

    Directory of Open Access Journals (Sweden)

    Blot Joelle

    2007-08-01

    Full Text Available Abstract The NIMA-related kinases represent a family of serine/threonine kinases implicated in cell cycle control. The founding member of this family, the NIMA kinase of Aspergillus nidulans, as well as the fission yeast homologue Fin1, contribute to multiple aspects of mitotic progression including the timing of mitotic entry, chromatin condensation, spindle organization and cytokinesis. Mammals contain a large family of eleven NIMA-related kinases, named Nek1 to Nek11. Of these, there is now substantial evidence that Nek2, Nek6, Nek7 and Nek9 also regulate mitotic events. At least three of these kinases, as well as NIMA and Fin1, have been localized to the microtubule organizing centre of their respective species, namely the centrosome or spindle pole body. Here, they have important functions in microtubule organization and mitotic spindle assembly. Other Nek kinases have been proposed to play microtubule-dependent roles in non-dividing cells, most notably in regulating the axonemal microtubules of cilia and flagella. In this review, we discuss the evidence that NIMA-related kinases make a significant contribution to the orchestration of mitotic progression and thereby protect cells from chromosome instability. Furthermore, we highlight their potential as novel chemotherapeutic targets.

  12. Protein Kinase A in Cancer

    Directory of Open Access Journals (Sweden)

    Antonio Caretta

    2011-02-01

    Full Text Available In the past, many chromosomal and genetic alterations have been examined as possible causes of cancer. However, some tumors do not display a clear molecular and/or genetic signature. Therefore, other cellular processes may be involved in carcinogenesis. Genetic alterations of proteins involved in signal transduction have been extensively studied, for example oncogenes, while modifications in intracellular compartmentalization of these molecules, or changes in the expression of unmodified genes have received less attention. Yet, epigenetic modulation of second messenger systems can deeply modify cellular functioning and in the end may cause instability of many processes, including cell mitosis. It is important to understand the functional meaning of modifications in second messenger intracellular pathways and unravel the role of downstream proteins in the initiation and growth of tumors. Within this framework, the cAMP system has been examined. cAMP is a second messenger involved in regulation of a variety of cellular functions. It acts mainly through its binding to cAMP-activated protein kinases (PKA, that were suggested to participate in the onset and progression of various tumors. PKA may represent a biomarker for tumor detection, identification and staging, and may be a potential target for pharmacological treatment of tumors.

  13. Protein Kinase A in Cancer

    International Nuclear Information System (INIS)

    Caretta, Antonio; Mucignat-Caretta, Carla

    2011-01-01

    In the past, many chromosomal and genetic alterations have been examined as possible causes of cancer. However, some tumors do not display a clear molecular and/or genetic signature. Therefore, other cellular processes may be involved in carcinogenesis. Genetic alterations of proteins involved in signal transduction have been extensively studied, for example oncogenes, while modifications in intracellular compartmentalization of these molecules, or changes in the expression of unmodified genes have received less attention. Yet, epigenetic modulation of second messenger systems can deeply modify cellular functioning and in the end may cause instability of many processes, including cell mitosis. It is important to understand the functional meaning of modifications in second messenger intracellular pathways and unravel the role of downstream proteins in the initiation and growth of tumors. Within this framework, the cAMP system has been examined. cAMP is a second messenger involved in regulation of a variety of cellular functions. It acts mainly through its binding to cAMP-activated protein kinases (PKA), that were suggested to participate in the onset and progression of various tumors. PKA may represent a biomarker for tumor detection, identification and staging, and may be a potential target for pharmacological treatment of tumors

  14. Protein Kinase A in Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Caretta, Antonio; Mucignat-Caretta, Carla, E-mail: carla.mucignat@unipd.it [Department of Human Anatomy and Physiology, University of Padova, Via Marzolo 3, 35131 Padova (Italy)

    2011-02-28

    In the past, many chromosomal and genetic alterations have been examined as possible causes of cancer. However, some tumors do not display a clear molecular and/or genetic signature. Therefore, other cellular processes may be involved in carcinogenesis. Genetic alterations of proteins involved in signal transduction have been extensively studied, for example oncogenes, while modifications in intracellular compartmentalization of these molecules, or changes in the expression of unmodified genes have received less attention. Yet, epigenetic modulation of second messenger systems can deeply modify cellular functioning and in the end may cause instability of many processes, including cell mitosis. It is important to understand the functional meaning of modifications in second messenger intracellular pathways and unravel the role of downstream proteins in the initiation and growth of tumors. Within this framework, the cAMP system has been examined. cAMP is a second messenger involved in regulation of a variety of cellular functions. It acts mainly through its binding to cAMP-activated protein kinases (PKA), that were suggested to participate in the onset and progression of various tumors. PKA may represent a biomarker for tumor detection, identification and staging, and may be a potential target for pharmacological treatment of tumors.

  15. MAP kinase cascades in Arabidopsis innate immunity

    DEFF Research Database (Denmark)

    Rasmussen, Magnus Wohlfahrt; Roux, Milena Edna; Petersen, Morten

    2012-01-01

    Plant mitogen-activated protein kinase (MAPK) cascades generally transduce extracellular stimuli into cellular responses. These stimuli include the perception of pathogen-associated molecular patterns (PAMPs) by host transmembrane pattern recognition receptors which trigger MAPK-dependent innate ...

  16. Side-effects of protein kinase inhibitors on ion channels

    Indian Academy of Sciences (India)

    2013-11-06

    Nov 6, 2013 ... including PKA, PKG, ribosomal S6 kinase, and epidermal growth factor receptor kinase (EGFRK) in an ATP- competitive manner, while having no effect on other kinases such as CK1, CK2, MAP kinase, and CSK (Meggio et al. 1995). The necessity for more specific inhibitors of PKC led to the discovery of ...

  17. The PIM kinases in hematological cancers.

    Science.gov (United States)

    Alvarado, Yesid; Giles, Francis J; Swords, Ronan T

    2012-02-01

    The PIM genes represent a family of proto-oncogenes that encode three different serine/threonine protein kinases (PIM1, PIM2 and PIM3) with essential roles in the regulation of signal transduction cascades, which promote cell survival, proliferation and drug resistance. PIM kinases are overexpressed in several hematopoietic tumors and support in vitro and in vivo malignant cell growth and survival, through cell cycle regulation and inhibition of apoptosis. PIM kinases do not have an identified regulatory domain, which means that these proteins are constitutively active once transcribed. They appear to be critical downstream effectors of important oncoproteins and, when overexpressed, can mediate drug resistance to available agents, such as rapamycin. Recent crystallography studies reveal that, unlike other kinases, they possess a hinge region, which creates a unique binding pocket for ATP, offering a target for an increasing number of potent small-molecule PIM kinase inhibitors. Preclinical studies in models of various hematologic cancers indicate that these novel agents show promising activity and some of them are currently being evaluated in a clinical setting. In this review, we profile the PIM kinases as targets for therapeutics in hematologic malignancies.

  18. Non-degradative Ubiquitination of Protein Kinases.

    Directory of Open Access Journals (Sweden)

    K Aurelia Ball

    2016-06-01

    Full Text Available Growing evidence supports other regulatory roles for protein ubiquitination in addition to serving as a tag for proteasomal degradation. In contrast to other common post-translational modifications, such as phosphorylation, little is known about how non-degradative ubiquitination modulates protein structure, dynamics, and function. Due to the wealth of knowledge concerning protein kinase structure and regulation, we examined kinase ubiquitination using ubiquitin remnant immunoaffinity enrichment and quantitative mass spectrometry to identify ubiquitinated kinases and the sites of ubiquitination in Jurkat and HEK293 cells. We find that, unlike phosphorylation, ubiquitination most commonly occurs in structured domains, and on the kinase domain, ubiquitination is concentrated in regions known to be important for regulating activity. We hypothesized that ubiquitination, like other post-translational modifications, may alter the conformational equilibrium of the modified protein. We chose one human kinase, ZAP-70, to simulate using molecular dynamics with and without a monoubiquitin modification. In Jurkat cells, ZAP-70 is ubiquitinated at several sites that are not sensitive to proteasome inhibition and thus may have other regulatory roles. Our simulations show that ubiquitination influences the conformational ensemble of ZAP-70 in a site-dependent manner. When monoubiquitinated at K377, near the C-helix, the active conformation of the ZAP-70 C-helix is disrupted. In contrast, when monoubiquitinated at K476, near the kinase hinge region, an active-like ZAP-70 C-helix conformation is stabilized. These results lead to testable hypotheses that ubiquitination directly modulates kinase activity, and that ubiquitination is likely to alter structure, dynamics, and function in other protein classes as well.

  19. Crystal structure of Cryptosporidium parvum pyruvate kinase.

    Directory of Open Access Journals (Sweden)

    William J Cook

    Full Text Available Pyruvate kinase plays a critical role in cellular metabolism of glucose by serving as a major regulator of glycolysis. This tetrameric enzyme is allosterically regulated by different effector molecules, mainly phosphosugars. In response to binding of effector molecules and substrates, significant structural changes have been identified in various pyruvate kinase structures. Pyruvate kinase of Cryptosporidium parvum is exceptional among known enzymes of protozoan origin in that it exhibits no allosteric property in the presence of commonly known effector molecules. The crystal structure of pyruvate kinase from C. parvum has been solved by molecular replacement techniques and refined to 2.5 Å resolution. In the active site a glycerol molecule is located near the γ-phosphate site of ATP, and the protein structure displays a partially closed active site. However, unlike other structures where the active site is closed, the α6' helix in C. parvum pyruvate kinase unwinds and assumes an extended conformation. In the crystal structure a sulfate ion is found at a site that is occupied by a phosphate of the effector molecule in many pyruvate kinase structures. A new feature of the C. parvum pyruvate kinase structure is the presence of a disulfide bond cross-linking the two monomers in the asymmetric unit. The disulfide bond is formed between cysteine residue 26 in the short N-helix of one monomer with cysteine residue 312 in a long helix (residues 303-320 of the second monomer at the interface of these monomers. Both cysteine residues are unique to C. parvum, and the disulfide bond remained intact in a reduced environment. However, the significance of this bond, if any, remains unknown at this time.

  20. MEK-1 phosphorylation by MEK kinase, Raf, and mitogen-activated protein kinase: analysis of phosphopeptides and regulation of activity.

    OpenAIRE

    Gardner, A M; Vaillancourt, R R; Lange-Carter, C A; Johnson, G L

    1994-01-01

    MEK-1 is a dual threonine and tyrosine recognition kinase that phosphorylates and activates mitogen-activated protein kinase (MAPK). MEK-1 is in turn activated by phosphorylation. Raf and MAPK/extracellular signal-regulated kinase kinase (MEKK) independently phosphorylate and activate MEK-1. Recombinant MEK-1 is also capable of autoactivation. Purified recombinant wild type MEK-1 and a mutant kinase inactive MEK-1 were used as substrates for MEKK, Raf, and autophosphorylation. MEK-1 phosphory...

  1. Diverse phosphoregulatory mechanisms controlling cyclin-dependent kinase-activating kinases in Arabidopsis

    Czech Academy of Sciences Publication Activity Database

    Shimotohno, A.; Ohno, R.; Bišová, Kateřina; Sakaguchi, N.; Huang, J.; Koncz, C.; Uchimiya, H.; Umeda, M.

    2006-01-01

    Roč. 47, - (2006), s. 701-710 ISSN 0960-7412 Institutional research plan: CEZ:AV0Z50200510 Keywords : cyclin -dependent kinase * cdk-activating kinase * cyclin Subject RIV: EE - Microbiology, Virology Impact factor: 6.565, year: 2006

  2. A systematic evaluation of protein kinase a-a-kinase anchoring protein interaction motifs

    NARCIS (Netherlands)

    Burgers, Pepijn P|info:eu-repo/dai/nl/341566551; van der Heyden, Marcel A G; Kok, Bart; Heck, Albert J R|info:eu-repo/dai/nl/105189332; Scholten, Arjen|info:eu-repo/dai/nl/313939780

    2015-01-01

    Protein kinase A (PKA) in vertebrates is localized to specific locations in the cell via A-kinase anchoring proteins (AKAPs). The regulatory subunits of the four PKA isoforms (RIα, RIβ, RIIα, and RIIβ) each form a homodimer, and their dimerization domain interacts with a small helical region present

  3. A systematic evaluation of protein kinase A-A-kinase anchoring protein interaction motifs

    NARCIS (Netherlands)

    Burgers, Pepijn P; van der Heyden, MAG; Kok, Bart; Heck, Albert J R; Scholten, Arjen

    2015-01-01

    Protein kinase A (PKA) in vertebrates is localized to specific locations in the cell via A-kinase anchoring proteins (AKAPs). The regulatory subunits of the four PKA isoforms (RIα, RIβ, RIIα, and RIIβ) each form a homodimer, and their dimerization domain interacts with a small helical region present

  4. Role of adiponectin/phosphatidylinositol 3-kinase/protein kinase B ...

    African Journals Online (AJOL)

    The adiponectin/phosphatidylinositol 3-kinase/protein kinase B (ADP/PI3k/Akt) signal transduction pathway has an important role in promoting cell survival. This study was designed to determine if the ADP/PI3K/Akt signaling pathway has a role in the mechanism of ischemia–reperfusion injury in vivo. Sprague–Dawley rats ...

  5. The target landscape of clinical kinase drugs.

    Science.gov (United States)

    Klaeger, Susan; Heinzlmeir, Stephanie; Wilhelm, Mathias; Polzer, Harald; Vick, Binje; Koenig, Paul-Albert; Reinecke, Maria; Ruprecht, Benjamin; Petzoldt, Svenja; Meng, Chen; Zecha, Jana; Reiter, Katrin; Qiao, Huichao; Helm, Dominic; Koch, Heiner; Schoof, Melanie; Canevari, Giulia; Casale, Elena; Depaolini, Stefania Re; Feuchtinger, Annette; Wu, Zhixiang; Schmidt, Tobias; Rueckert, Lars; Becker, Wilhelm; Huenges, Jan; Garz, Anne-Kathrin; Gohlke, Bjoern-Oliver; Zolg, Daniel Paul; Kayser, Gian; Vooder, Tonu; Preissner, Robert; Hahne, Hannes; Tõnisson, Neeme; Kramer, Karl; Götze, Katharina; Bassermann, Florian; Schlegl, Judith; Ehrlich, Hans-Christian; Aiche, Stephan; Walch, Axel; Greif, Philipp A; Schneider, Sabine; Felder, Eduard Rudolf; Ruland, Juergen; Médard, Guillaume; Jeremias, Irmela; Spiekermann, Karsten; Kuster, Bernhard

    2017-12-01

    Kinase inhibitors are important cancer therapeutics. Polypharmacology is commonly observed, requiring thorough target deconvolution to understand drug mechanism of action. Using chemical proteomics, we analyzed the target spectrum of 243 clinically evaluated kinase drugs. The data revealed previously unknown targets for established drugs, offered a perspective on the "druggable" kinome, highlighted (non)kinase off-targets, and suggested potential therapeutic applications. Integration of phosphoproteomic data refined drug-affected pathways, identified response markers, and strengthened rationale for combination treatments. We exemplify translational value by discovering SIK2 (salt-inducible kinase 2) inhibitors that modulate cytokine production in primary cells, by identifying drugs against the lung cancer survival marker MELK (maternal embryonic leucine zipper kinase), and by repurposing cabozantinib to treat FLT3-ITD-positive acute myeloid leukemia. This resource, available via the ProteomicsDB database, should facilitate basic, clinical, and drug discovery research and aid clinical decision-making. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Mechanism of polyphosphate kinase from Propionibacterium shermanii

    International Nuclear Information System (INIS)

    Robinson, N.A.

    1986-01-01

    Polyphosphate kinase, which catalyzes the reaction shown below, is one of two enzymes which have been reported to catalyze the synthesis of polyphosphate. Purification performed by ammonium sulfate precipitation (0-40% fraction) was followed by chromatography. The enzyme represents 70% of the protein in the hydroxylapatite pool and is stable at this level of purity. The subunit molecular weight was determined by SDS polyacrylamide gel analysis, (83,000 +/- 3000), nondenaturing polyacrylamide gel electrophoresis, (80,000 and 86,000 daltons), gel filtration (Biogel A 0.5m column was 85,000 +/- 4000.) Polyphosphate kinase appears to be a monomeric enzyme of ∼83,000 daltons. Four assays were developed for polyphosphate kinase. Basic proteins such as polylysine stimulate the synthesis of polyphosphate, these proteins cause precipitation of polyphosphate kinase from relatively impure enzyme extracts: Synthesized polyphosphate interacts noncovalently with the basic protein-enzyme precipitate. Efficient synthesis of polyphosphate requires the addition of either phosphate or short chain polyphosphate. Synthesis did occur at 1/10 the rate when neither of these two compounds were included. Initiation, elongation, and termination events of polyphosphate synthesis were examined. Short chain polyphosphate acts as a primer, with [ 32 P] short-chain polyphosphate incorporation into long chain polyphosphate by the kinase

  7. Mechanism of polyphosphate kinase from Propionibacterium shermanii

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, N.A.

    1986-01-01

    Polyphosphate kinase, which catalyzes the reaction shown below, is one of two enzymes which have been reported to catalyze the synthesis of polyphosphate. Purification performed by ammonium sulfate precipitation (0-40% fraction) was followed by chromatography. The enzyme represents 70% of the protein in the hydroxylapatite pool and is stable at this level of purity. The subunit molecular weight was determined by SDS polyacrylamide gel analysis, (83,000 +/- 3000), nondenaturing polyacrylamide gel electrophoresis, (80,000 and 86,000 daltons), gel filtration (Biogel A 0.5m column was 85,000 +/- 4000.) Polyphosphate kinase appears to be a monomeric enzyme of approx.83,000 daltons. Four assays were developed for polyphosphate kinase. Basic proteins such as polylysine stimulate the synthesis of polyphosphate, these proteins cause precipitation of polyphosphate kinase from relatively impure enzyme extracts: Synthesized polyphosphate interacts noncovalently with the basic protein-enzyme precipitate. Efficient synthesis of polyphosphate requires the addition of either phosphate or short chain polyphosphate. Synthesis did occur at 1/10 the rate when neither of these two compounds were included. Initiation, elongation, and termination events of polyphosphate synthesis were examined. Short chain polyphosphate acts as a primer, with (/sup 32/P) short-chain polyphosphate incorporation into long chain polyphosphate by the kinase.

  8. Mining protein kinases regulation using graphical models.

    Science.gov (United States)

    Chen, Qingfeng; Chen, Yi-Ping Phoebe

    2011-03-01

    Abnormal kinase activity is a frequent cause of diseases, which makes kinases a promising pharmacological target. Thus, it is critical to identify the characteristics of protein kinases regulation by studying the activation and inhibition of kinase subunits in response to varied stimuli. Bayesian network (BN) is a formalism for probabilistic reasoning that has been widely used for learning dependency models. However, for high-dimensional discrete random vectors the set of plausible models becomes large and a full comparison of all the posterior probabilities related to the competing models becomes infeasible. A solution to this problem is based on the Markov Chain Monte Carlo (MCMC) method. This paper proposes a BN-based framework to discover the dependency correlations of kinase regulation. Our approach is to apply the MCMC method to generate a sequence of samples from a probability distribution, by which to approximate the distribution. The frequent connections (edges) are identified from the obtained sampling graphical models. Our results point to a number of novel candidate regulation patterns that are interesting in biology and include inferred associations that were unknown.

  9. Regulation of the MAP kinase cascade in PC12 cells: B-Raf activates MEK-1 (MAP kinase or ERK kinase) and is inhibited by cAMP

    DEFF Research Database (Denmark)

    Peraldi, P; Frödin, M; Barnier, J V

    1995-01-01

    In PC12 cells, cAMP stimulates the MAP kinase pathway by an unknown mechanism. Firstly, we examined the role of calcium ion mobilization and of protein kinase C in cAMP-stimulated MAP kinase activation. We show that cAMP stimulates p44mapk independently of these events. Secondly, we studied the r...

  10. Protocols for the Design of Kinase-Focused Compound Libraries.

    Science.gov (United States)

    Jacoby, Edgar; Wroblowski, Berthold; Buyck, Christophe; Neefs, Jean-Marc; Meyer, Christophe; Cummings, Maxwell D; van Vlijmen, Herman

    2017-11-08

    Protocols for the design of kinase-focused compound libraries are presented. Kinase-focused compound libraries can be differentiated based on the design goal. Depending on whether the library should be a discovery library specific for one particular kinase, a general discovery library for multiple distinct kinase projects, or even phenotypic screening, there exists today a variety of in silico methods to design candidate compound libraries. We address the following scenarios: 1) Datamining of SAR databases and kinase focused vendor catalogues; 2) Predictions and virtual screening; 3) Structure-based design of combinatorial kinase inhibitors; 4) Design of covalent kinase inhibitors; 5) Design of macrocyclic kinase inhibitors; and 6) Design of allosteric kinase inhibitors and activators. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Phosphatidylinositol 3-Kinase (PI3K) and phosphatidylinositol 3-kinase-related kinase (PIKK) inhibitors: importance of the morpholine ring

    Czech Academy of Sciences Publication Activity Database

    Andrs, M.; Kobarecny, J.; Jun, D.; Hodný, Zdeněk; Bartek, Jiří; Kuca, K.

    2015-01-01

    Roč. 58, č. 1 (2015), s. 41-71 ISSN 0022-2623 R&D Projects: GA MŠk(CZ) CZ.1.07/2.3.00/30.0044 Grant - others:University Hospital Hradec Kralove(CZ) 00179906; Faculty of Military Health Sciences, University of Defence(CZ) SV/FVZ201402 Institutional support: RVO:68378050 Keywords : DEPENDENT PROTEIN-KINASE * STRAND BREAK REPAIR * SELECTIVE PI3K-BETA INHIBITORS * TELANGIECTASIA MUTATED KINASE Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.589, year: 2015

  12. Crystal Structure of Human Nicotinamide Riboside Kinase

    Energy Technology Data Exchange (ETDEWEB)

    Khan,J.; Xiang, S.; Tong, L.

    2007-01-01

    Nicotinamide riboside kinase (NRK) has an important role in the biosynthesis of NAD{sup +} as well as the activation of tiazofurin and other NR analogs for anticancer therapy. NRK belongs to the deoxynucleoside kinase and nucleoside monophosphate (NMP) kinase superfamily, although the degree of sequence conservation is very low. We report here the crystal structures of human NRK1 in a binary complex with the reaction product nicotinamide mononucleotide (NMN) at 1.5 {angstrom} resolution and in a ternary complex with ADP and tiazofurin at 2.7 {angstrom} resolution. The active site is located in a groove between the central parallel {beta} sheet core and the LID and NMP-binding domains. The hydroxyl groups on the ribose of NR are recognized by Asp56 and Arg129, and Asp36 is the general base of the enzyme. Mutation of residues in the active site can abolish the catalytic activity of the enzyme, confirming the structural observations.

  13. Crystal structure of human nicotinamide riboside kinase.

    Science.gov (United States)

    Khan, Javed A; Xiang, Song; Tong, Liang

    2007-08-01

    Nicotinamide riboside kinase (NRK) has an important role in the biosynthesis of NAD(+) as well as the activation of tiazofurin and other NR analogs for anticancer therapy. NRK belongs to the deoxynucleoside kinase and nucleoside monophosphate (NMP) kinase superfamily, although the degree of sequence conservation is very low. We report here the crystal structures of human NRK1 in a binary complex with the reaction product nicotinamide mononucleotide (NMN) at 1.5 A resolution and in a ternary complex with ADP and tiazofurin at 2.7 A resolution. The active site is located in a groove between the central parallel beta sheet core and the LID and NMP-binding domains. The hydroxyl groups on the ribose of NR are recognized by Asp56 and Arg129, and Asp36 is the general base of the enzyme. Mutation of residues in the active site can abolish the catalytic activity of the enzyme, confirming the structural observations.

  14. Protein Kinases in Shaping Plant Architecture.

    Science.gov (United States)

    Wu, Juan; Wang, Bo; Xin, Xiaoyun; Ren, Dongtao

    2018-02-13

    Plant architecture, the three-dimensional organization of the plant body, includes the branching pattern and the size, shape, and position of organs. Plant architecture is genetically controlled and is influenced by environmental conditions. The regulations occur at most of the stages from the first division of the fertilized eggs to the final establishment of plant architecture. Among the various endogenous regulators, protein kinases and their associated signaling pathways have been shown to play important roles in regulating the process of plant architecture establishment. In this review, we summarize recent progress in the understanding of the mechanisms by which plant architecture formation is regulated by protein kinases, especially mitogen-activated protein kinase (MAPK). Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. X-ray crystal structure of bone marrow kinase in the x chromosome: a Tec family kinase.

    Science.gov (United States)

    Muckelbauer, Jodi; Sack, John S; Ahmed, Nazia; Burke, James; Chang, Chiehying Y; Gao, Mian; Tino, Joseph; Xie, Dianlin; Tebben, Andrew J

    2011-11-01

    Bone marrow kinase in the X chromosome, a member of the Tec family of tyrosine kinases, plays a role in both monocyte/macrophage trafficking as well as cytokine secretion. Although the structures of Tec family kinases Bruton's tyrosine kinase and IL-2-inducible T-cell kinase are known, the crystal structures of other Tec family kinases have remained elusive. We report the X-ray crystal structures of bone marrow kinase in the X chromosome in complex with dasatinib at 2.4 Å resolution and PP2 at 1.9 Å resolution. The bone marrow kinase in the X chromosome structures reveal a typical kinase protein fold; with well-ordered protein conformation that includes an open/extended activation loop and a stabilized DFG-motif rendering the kinase in an inactive conformation. Dasatinib and PP2 bind to bone marrow kinase in the X chromosome in the ATP binding pocket and display similar binding modes to that observed in other Tec and Src protein kinases. The bone marrow kinase in the X chromosome structures identify conformational elements of the DFG-motif that could potentially be utilized to design potent and/or selective bone marrow kinase in the X chromosome inhibitors. © 2011 John Wiley & Sons A/S.

  16. Phosphorylation of varicella-zoster virus glycoprotein gpI by mammalian casein kinase II and casein kinase I

    International Nuclear Information System (INIS)

    Grose, C.; Jackson, W.; Traugh, J.A.

    1989-01-01

    Varicella-zoster virus (VZV) glycoprotein gpI is the predominant viral glycoprotein within the plasma membranes of infected cells. This viral glycoprotein is phosphorylated on its polypeptide backbone during biosynthesis. In this report, the authors investigated the protein kinases which participate in the phosphorylation events. Under in vivo conditions, VZV gpI was phosphorylated on its serine and threonine residues by protein kinases present within lysates of either VZV-infected or uninfected cells. Because this activity was diminished by heparin, a known inhibitor of casein kinase II, isolated gpI was incubated with purified casein kinase II and shown to be phosphorylated in an in vitro assay containing [γ- 32 P]ATP. The same glycoprotein was phosphorylated when [ 32 P]GTP was substituted for [ 32 P]ATP in the protein kinase assay. They also tested whether VZV gpI was phosphorylated by two other ubiquitous mammalian protein kinases--casein kinase I and cyclic AMP-dependent kinase--and found that only casein kinase I modified gpI. When the predicted 623-amino-acid sequence of gpI was examined, two phosphorylation sites known to be optimal for casein kinase II were observed. In summary, this study showed that VZV gpI was phosphorylated by each of two mammalian protein kinases (casein kinase I and casein kinase II) and that potential serine-threonine phosphorylation sites for each of these two kinases were present in the viral glycoprotein

  17. Production of Protein Kinases in E. coli.

    Science.gov (United States)

    Dodson, Charlotte A

    2017-01-01

    Recombinant protein expression is widely used to generate milligram quantities of protein kinases for crystallographic, enzymatic, or other biophysical assays in vitro. Expression in E. coli is fast, cheap, and reliable. Here I present a detailed protocol for the production of human Aurora-A kinase. I begin with transformation of a suitable plasmid into an expression strain of E. coli, followed by growth and harvesting of bacterial cell cultures. Finally, I describe the purification of Aurora-A to homogeneity using immobilized metal affinity and size exclusion chromatographies.

  18. Rational design of protein kinase inhibitors

    Directory of Open Access Journals (Sweden)

    Yarmoluk S. M.

    2013-07-01

    Full Text Available Modern methodological approaches to rational design of low molecular weight compounds with specific activity in relation to predetermined biomolecular targets are considered by example of development of high effective protein kinase inhibitors. The application of new computational methods that allow to significantly improve the quality of computational experiments (in, particular, accuracy of low molecular weight compounds activity prediction without increase of computational and time costs are highlighted. The effectiveness of strategy of rational design is demonstrated by examples of several own investigations devoted to development of new inhibitors that are high effective and selective towards protein kinases CK2, FGFR1 and ASK1.

  19. Protein Kinase C (PKC Isozymes and Cancer

    Directory of Open Access Journals (Sweden)

    Jeong-Hun Kang

    2014-01-01

    Full Text Available Protein kinase C (PKC is a family of phospholipid-dependent serine/threonine kinases, which can be further classified into three PKC isozymes subfamilies: conventional or classic, novel or nonclassic, and atypical. PKC isozymes are known to be involved in cell proliferation, survival, invasion, migration, apoptosis, angiogenesis, and drug resistance. Because of their key roles in cell signaling, PKC isozymes also have the potential to be promising therapeutic targets for several diseases, such as cardiovascular diseases, immune and inflammatory diseases, neurological diseases, metabolic disorders, and multiple types of cancer. This review primarily focuses on the activation, mechanism, and function of PKC isozymes during cancer development and progression.

  20. Purification and characterization of a casein kinase 2-type protein kinase from pea nuclei

    Science.gov (United States)

    Li, H.; Roux, S. J.

    1992-01-01

    Almost all the polyamine-stimulated protein kinase activity associated with the chromatin fraction of nuclei purified from etiolated pea (Pisum sativum L.) plumules is present in a single enzyme that can be extracted from chromatin by 0.35 molar NaCl. This protein kinase can be further purified over 2000-fold by salt fractionation and anion-exchange and casein-agarose column chromatography, after which it is more than 90% pure. The purified kinase has a specific activity of about 650 nanomoles per minute per milligram protein in the absence of polyamines, with either ATP or GTP as phosphoryl donor. Spermidine can stimulate its activity fourfold, with half-maximal activation at about 2 millimolar. Spermine and putrescine also stimulate activity, although somewhat less effectively. This kinase has a tetrameric alpha 2 beta 2 structure with a native molecular weight of 130,000, and subunit molecular weights of 36,000 for the catalytic subunit (alpha) and 29,000 for the regulatory subunit (beta). In western blot analyses, only the alpha subunit reacts strongly with polyclonal antibodies to a Drosophila casein kinase II. The pea kinase can use casein and phosvitin as artificial substrates, phosphorylating both the serine and threonine residues of casein. It has a pH optimum near 8.0, a Vmax of 1.5 micromoles per minute per milligram protein, and a Km for ATP of approximately 75 micromolar. Its activity can be almost completely inhibited by heparin at 5 micrograms per milliliter, but is relatively insensitive to concentrations of staurosporine, K252a, and chlorpromazine that strongly antagonize Ca(2+) -regulated protein kinases. These results are discussed in relation to recent findings that casein kinase 2-type kinases may phosphorylate trans-acting factors that bind to light-regulated promoters in plants.

  1. CZK3, a MAP kinase kinase kinase homolog in Cercospora zeae-maydis, regulates cercosporin biosynthesis, fungal development, and pathogenesis.

    Science.gov (United States)

    Shim, Won-Bo; Dunkle, Larry D

    2003-09-01

    The fungus Cercospora zeae-maydis causes gray leaf spot of maize and produces cercosporin, a photosensitizing perylenequinone with toxic activity against a broad spectrum of organisms. However, little is known about the biosynthetic pathway or factors that regulate cercosporin production. Analysis of a cDNA subtraction library comprised of genes that are up-regulated during cercosporin synthesis revealed a sequence highly similar to mitogen-activated protein (MAP) kinases in other fungi. Sequencing and conceptual translation of the full-length genomic sequence indicated that the gene, which we designated CZK3, contains a 4,119-bp open reading frame devoid of introns and encodes a 1,373-amino acid sequence that is highly similar to Wis4, a MAP kinase kinase kinase in Schizosaccharomyces pombe. Targeted disruption of CZK3 suppressed expression of genes predicted to participate in cercosporin biosynthesis and abolished cercosporin production. The disrupted mutants grew faster on agar media than the wild type but were deficient in conidiation and elicited only small chlorotic spots on inoculated maize leaves compared with rectangular necrotic lesions incited by the wild type. Complementation of disruptants with the CZK3 open reading frame and flanking sequences restored wild-type levels of conidiation, growth rate, and virulence as well as the ability to produce cercosporin. The results suggest that cercosporin is a virulence factor in C. zeae-maydis during maize pathogenesis, but the pleiotropic effects of CZK3 disruption precluded definitive conclusions.

  2. Identification of an allosteric signaling network within Tec family kinases.

    Science.gov (United States)

    Joseph, Raji E; Xie, Qian; Andreotti, Amy H

    2010-10-22

    The Tec family kinases are tyrosine kinases that function primarily in hematopoietic cells. The catalytic activity of the Tec kinases is positively influenced by the regulatory domains outside of the kinase domain. The current lack of a full-length Tec kinase structure leaves a void in our understanding of how these positive regulatory signals are transmitted to the kinase domain. Recently, a conserved structure within kinases, the 'regulatory spine', which assembles and disassembles as a kinase switches between its active and inactive states, has been identified. Here, we define the residues that comprise the regulatory spine within Tec kinases. Compared to previously characterized systems, the Tec kinases contain an extended regulatory spine that includes a conserved methionine within the C-helix and a conserved tryptophan within the Src homology 2-kinase linker of Tec kinases. This extended regulatory spine forms a conduit for transmitting the presence of the regulatory domains of Tec kinases to the catalytic domain. We further show that mutation of the gatekeeper residue at the edge of the regulatory spine stabilizes the regulatory spine, resulting in a constitutively active kinase domain. Importantly, the regulatory spine is preassembled in this gatekeeper mutant, rendering phosphorylation on the activation loop unnecessary for its activity. Moreover, we show that the disruption of the conserved electrostatic interaction between Bruton's tyrosine kinase R544 on the activation loop and Bruton's tyrosine kinase E445 on the C-helix also aids in the assembly of the regulatory spine. Thus, the extended regulatory spine is a key structure that is critical for maintaining the activity of Tec kinases. Copyright © 2010 Elsevier Ltd. All rights reserved.

  3. Creatine kinase activity is associated with blood pressure

    NARCIS (Netherlands)

    Brewster, Lizzy M.; Mairuhu, Gideon; Bindraban, Navin R.; Koopmans, Richard P.; Clark, Joseph F.; van Montfrans, Gert A.

    2006-01-01

    BACKGROUND: We previously hypothesized that high activity of creatine kinase, the central regulatory enzyme of energy metabolism, facilitates the development of high blood pressure. Creatine kinase rapidly provides adenosine triphosphate to highly energy-demanding processes, including cardiovascular

  4. Kinase activity ranking using phosphoproteomics data (KARP) quantifies the contribution of protein kinases to the regulation of cell viability.

    Science.gov (United States)

    Wilkes, Edmund H; Casado, Pedro; Rajeeve, Vinothini; Cutillas, Pedro R

    2017-09-01

    Cell survival is regulated by a signaling network driven by the activity of protein kinases; however, determining the contribution that each kinase in the network makes to such regulation remains challenging. Here, we report a computational approach that uses mass spectrometry-based phosphoproteomics data to rank protein kinases based on their contribution to cell regulation. We found that the scores returned by this algorithm, which we have termed kinase activity ranking using phosphoproteomics data (KARP), were a quantitative measure of the contribution that individual kinases make to the signaling output. Application of KARP to the analysis of eight hematological cell lines revealed that cyclin-dependent kinase (CDK) 1/2, casein kinase (CK) 2, extracellular signal-related kinase (ERK), and p21-activated kinase (PAK) were the most frequently highly ranked kinases in these cell models. The patterns of kinase activation were cell-line specific yet showed a significant association with cell viability as a function of kinase inhibitor treatment. Thus, our study exemplifies KARP as an untargeted approach to empirically and systematically identify regulatory kinases within signaling networks. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Allosteric small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.

    2015-01-01

    current barriers of kinase inhibitors, including poor selectivity and emergence of drug resistance. In spite of the small number of identified allosteric inhibitors in comparison with that of inhibitors targeting the ATP pocket, encouraging results, such as the FDA-approval of the first small...

  6. Inhibitors of Cyclin-dependent Kinases

    Czech Academy of Sciences Publication Activity Database

    Kryštof, V.; Strnad, Miroslav

    2001-01-01

    Roč. 95, č. 5 (2001), s. 295-300 ISSN 0009-2770 R&D Projects: GA ČR GA301/02/0475; GA MŠk VS96154 Institutional research plan: CEZ:AV0Z5038910 Keywords : Cyclin-dependent Kinase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.317, year: 2001

  7. Kinase-Centric Computational Drug Development

    NARCIS (Netherlands)

    Kooistra, Albert J.; Volkamer, Andrea

    2017-01-01

    Kinases are among the most studied drug targets in industry and academia, due to their involvement in a majority of cellular processes and, upon dysregulation, in a variety of diseases including cancer, inflammation, and autoimmune disorders. The high interest in this druggable protein family

  8. Nonorthologous gene displacement of phosphomevalonate kinase

    NARCIS (Netherlands)

    Houten, S. M.; Waterham, H. R.

    2001-01-01

    Phosphomevalonate kinase (PMK; EC 2.7.4.2) catalyzes the phosphorylation of 5-phosphomevalonate into 5-diphosphomevalonate, an essential step in isoprenoid biosynthesis via the mevalonate pathway. So far, two nonorthologous genes encoding PMK have been described, the Saccharomyces cerevisiae ERG8

  9. Protein kinase CK1 from Trypanosoma cruzi.

    Science.gov (United States)

    Calabokis, Maritza; Kurz, Liliana; Gonzatti, Mary I; Bubis, José

    2003-08-01

    A protein kinase activity, which uses casein as a substrate, has been purified to homogeneity from the epimastigote stage of Trypanosoma cruzi, by sequential chromatography on Q sepharose, heparin sepharose, phenyl sepharose, and alpha-casein agarose. An apparent molecular weight of 36,000 was estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Gel filtration chromatography and sedimentation analyses demonstrated that the purified native enzyme is a monomer with a sedimentation coefficient of 2.9 S. The hydrodynamic parameters indicated that the shape of the protein is globular with a frictional ratio f/f(o) = 1.36 and a Stokes radius of 27.7 A. When two selective peptide substrates for protein kinases CK1 and CK2 were used (RRKDLHDDEEDEAM. SITA and RRRADDSDDDDD, respectively), the purified kinase was shown to predominantly phosphorylate the CK1-specific peptide. Additionally, the enzyme was inhibited by N-(2-amino-ethyl)-5-chloroisoquinoline-8-sulfonamide, a specific inactivator of CK1s from mammals. Based on these results, we concluded that the purified kinase corresponds to a parasite CK1.

  10. Gene regulation by MAP kinase cascades

    DEFF Research Database (Denmark)

    Fiil, Berthe Katrine; Petersen, Klaus; Petersen, Morten

    2009-01-01

    Mitogen-activated protein kinase (MAPK) cascades are signaling modules that transduce extracellular stimuli to a range of cellular responses. Research in yeast and metazoans has shown that MAPK-mediated phosphorylation directly or indirectly regulates the activity of transcription factors. Plant ...

  11. MAP kinases in inflammatory bowel disease

    DEFF Research Database (Denmark)

    Coskun, Mehmet; Olsen, Jørgen; Seidelin, Jakob Benedict

    2011-01-01

    The mammalian family of mitogen-activated protein kinases (MAPKs) is activated by diverse extracellular and intracellular stimuli, and thereby they play an essential role in connecting cell-surface receptors to changes in transcriptional programs. The MAPK signaling pathways regulate a wide range...

  12. Drosophila melanogaster deoxyribonucleoside kinase activates gemcitabine

    DEFF Research Database (Denmark)

    Knecht, Wolfgang; Mikkelsen, N.E.; Clausen, A.R.

    2009-01-01

    Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 angstrom resolution...

  13. Phosphotyrosine enrichment identifies focal adhesion kinase and other tyrosine kinases for targeting in canine hemangiosarcoma.

    Science.gov (United States)

    Marley, K; Maier, C S; Helfand, S C

    2012-09-01

    Canine hemangiosarcoma (HSA) is an endothelial cell malignancy driven, in part, by activating mutations in receptor and non-receptor tyrosine kinases. Proteomics, Western blots and a tyrosine kinase inhibitor were used to elucidate activating mechanisms in HSA cell lines. Phosphotyrosine peptides from focal adhesion kinase (FAK) STAT3, Lyn, Fyn and other signal transduction kinases were identified by mass spectrometry. FAK was constitutively activated at tyrosine 397, the autophosphorylation site, and this was reversible with high concentrations of a FAK inhibitor. FAK inhibitor-14 suppressed migration and phosphorylation of FAK tyrosine 397 and tyrosines 576/577 and was cytotoxic to HSA cells suggesting FAK signalling may be an important contributor to canine HSA survival. © 2012 Blackwell Publishing Ltd.

  14. Unraveling Kinase Activation Dynamics Using Kinase-Substrate Relationships from Temporal Large-Scale Phosphoproteomics Studies.

    Science.gov (United States)

    Domanova, Westa; Krycer, James; Chaudhuri, Rima; Yang, Pengyi; Vafaee, Fatemeh; Fazakerley, Daniel; Humphrey, Sean; James, David; Kuncic, Zdenka

    2016-01-01

    In response to stimuli, biological processes are tightly controlled by dynamic cellular signaling mechanisms. Reversible protein phosphorylation occurs on rapid time-scales (milliseconds to seconds), making it an ideal carrier of these signals. Advances in mass spectrometry-based proteomics have led to the identification of many tens of thousands of phosphorylation sites, yet for the majority of these the kinase is unknown and the underlying network topology of signaling networks therefore remains obscured. Identifying kinase substrate relationships (KSRs) is therefore an important goal in cell signaling research. Existing consensus sequence motif based prediction algorithms do not consider the biological context of KSRs, and are therefore insensitive to many other mechanisms guiding kinase-substrate recognition in cellular contexts. Here, we use temporal information to identify biologically relevant KSRs from Large-scale In Vivo Experiments (KSR-LIVE) in a data-dependent and automated fashion. First, we used available phosphorylation databases to construct a repository of existing experimentally-predicted KSRs. For each kinase in this database, we used time-resolved phosphoproteomics data to examine how its substrates changed in phosphorylation over time. Although substrates for a particular kinase clustered together, they often exhibited a different temporal pattern to the phosphorylation of the kinase. Therefore, although phosphorylation regulates kinase activity, our findings imply that substrate phosphorylation likely serve as a better proxy for kinase activity than kinase phosphorylation. KSR-LIVE can thereby infer which kinases are regulated within a biological context. Moreover, KSR-LIVE can also be used to automatically generate positive training sets for the subsequent prediction of novel KSRs using machine learning approaches. We demonstrate that this approach can distinguish between Akt and Rps6kb1, two kinases that share the same linear consensus motif

  15. Unraveling Kinase Activation Dynamics Using Kinase-Substrate Relationships from Temporal Large-Scale Phosphoproteomics Studies.

    Directory of Open Access Journals (Sweden)

    Westa Domanova

    Full Text Available In response to stimuli, biological processes are tightly controlled by dynamic cellular signaling mechanisms. Reversible protein phosphorylation occurs on rapid time-scales (milliseconds to seconds, making it an ideal carrier of these signals. Advances in mass spectrometry-based proteomics have led to the identification of many tens of thousands of phosphorylation sites, yet for the majority of these the kinase is unknown and the underlying network topology of signaling networks therefore remains obscured. Identifying kinase substrate relationships (KSRs is therefore an important goal in cell signaling research. Existing consensus sequence motif based prediction algorithms do not consider the biological context of KSRs, and are therefore insensitive to many other mechanisms guiding kinase-substrate recognition in cellular contexts. Here, we use temporal information to identify biologically relevant KSRs from Large-scale In Vivo Experiments (KSR-LIVE in a data-dependent and automated fashion. First, we used available phosphorylation databases to construct a repository of existing experimentally-predicted KSRs. For each kinase in this database, we used time-resolved phosphoproteomics data to examine how its substrates changed in phosphorylation over time. Although substrates for a particular kinase clustered together, they often exhibited a different temporal pattern to the phosphorylation of the kinase. Therefore, although phosphorylation regulates kinase activity, our findings imply that substrate phosphorylation likely serve as a better proxy for kinase activity than kinase phosphorylation. KSR-LIVE can thereby infer which kinases are regulated within a biological context. Moreover, KSR-LIVE can also be used to automatically generate positive training sets for the subsequent prediction of novel KSRs using machine learning approaches. We demonstrate that this approach can distinguish between Akt and Rps6kb1, two kinases that share the same

  16. TPX2 Protein of Arabidopsis Activates Aurora Kinase 1, But Not Aurora Kinase 3 In Vitro

    Czech Academy of Sciences Publication Activity Database

    Tomaštíková, Eva; Demidov, D.; Jeřábková, Hana; Binarová, Pavla; Houben, A.; Doležel, Jaroslav; Petrovská, Beáta

    2015-01-01

    Roč. 33, č. 6 (2015), s. 1988-1995 ISSN 0735-9640 R&D Projects: GA ČR(CZ) GA14-28443S; GA MŠk(CZ) LO1204; GA ČR GAP501/12/2333 Institutional support: RVO:61389030 ; RVO:61388971 Keywords : Aurora kinase * Targeting protein for Xklp2 * In vitro kinase assay Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.304, year: 2015

  17. Circadian and pharmacological regulation of casein kinase I in the ...

    Indian Academy of Sciences (India)

    2008-12-31

    Dec 31, 2008 ... [Agostino P. V., Plano S. A. and Golombek D. A. 2008 Circadian and pharmacological regulation of casein kinase I in the hamster suprachi- asmatic nucleus. ... The protein kinases, casein kinase I epsilon (CKIε) and delta (CKIδ) ... 1 mM EGTA, 50 mM sodium fluoride, 200 mM sodium vana- date and a ...

  18. Molecular Pathways : Targeting the Protein Kinase Wee1 in Cancer

    NARCIS (Netherlands)

    Geenen, Jill J.; Schellens, Jan H M

    2017-01-01

    Wee1 is a protein kinase that regulates the G2checkpoint and prevents entry into mitosis in response to DNA damage. Cyclin-dependent kinases (CDK) are a family of 14 serine/threonine protein kinases that coordinate the progression through the cell cycle. The Cdc2/cyclin B complex controls the

  19. The Roles of Protein Kinases in Learning and Memory

    Science.gov (United States)

    Giese, Karl Peter; Mizuno, Keiko

    2013-01-01

    In the adult mammalian brain, more than 250 protein kinases are expressed, but only a few of these kinases are currently known to enable learning and memory. Based on this information it appears that learning and memory-related kinases either impact on synaptic transmission by altering ion channel properties or ion channel density, or regulate…

  20. Side-effects of protein kinase inhibitors on ion channels

    Indian Academy of Sciences (India)

    Protein kinases are one of the largest gene families and have regulatory roles in all aspects of eukaryotic cell function. Modulation of protein kinase activity is a desirable therapeutic approach for a number of human diseases associated with aberrant kinase activity, including cancers, arthritis and cardiovascular disorders.

  1. Clinical heterogeneity and novel mutations in the glycerol kinase gene in three families with isolated glycerol kinase deficiency

    NARCIS (Netherlands)

    Sjarif, D. R.; Sinke, R. J.; Duran, M.; Beemer, F. A.; Kleijer, W. J.; Ploos van Amstel, J. K.; Poll-The, B. T.

    1998-01-01

    Isolated glycerol kinase deficiency (GKD) is an X linked recessive disorder. The clinical and biochemical picture may vary from a childhood metabolic crisis to asymptomatic adult "pseudohypertriglyceridaemia", the result of hyperglycerolaemia. We performed glycerol kinase (GK) gene analysis to study

  2. Computational analysis of ABL kinase mutations allows predicting drug sensitivity against selective kinase inhibitors.

    Science.gov (United States)

    Kamasani, Swapna; Akula, Sravani; Sivan, Sree Kanth; Manga, Vijjulatha; Duyster, Justus; Vudem, Dashavantha Reddy; Kancha, Rama Krishna

    2017-05-01

    The ABL kinase inhibitor imatinib has been used as front-line therapy for Philadelphia-positive chronic myeloid leukemia. However, a significant proportion of imatinib-treated patients relapse due to occurrence of mutations in the ABL kinase domain. Although inhibitor sensitivity for a set of mutations was reported, the role of less frequent ABL kinase mutations in drug sensitivity/resistance is not known. Moreover, recent reports indicate distinct resistance profiles for second-generation ABL inhibitors. We thus employed a computational approach to predict drug sensitivity of 234 point mutations that were reported in chronic myeloid leukemia patients. Initial validation analysis of our approach using a panel of previously studied frequent mutations indicated that the computational data generated in this study correlated well with the published experimental/clinical data. In addition, we present drug sensitivity profiles for remaining point mutations by computational docking analysis using imatinib as well as next generation ABL inhibitors nilotinib, dasatinib, bosutinib, axitinib, and ponatinib. Our results indicate distinct drug sensitivity profiles for ABL mutants toward kinase inhibitors. In addition, drug sensitivity profiles of a set of compound mutations in ABL kinase were also presented in this study. Thus, our large scale computational study provides comprehensive sensitivity/resistance profiles of ABL mutations toward specific kinase inhibitors.

  3. Kinase impact assessment in the landscape of fusion genes that retain kinase domains: a pan-cancer study.

    Science.gov (United States)

    Kim, Pora; Jia, Peilin; Zhao, Zhongming

    2016-12-24

    Assessing the impact of kinase in gene fusion is essential for both identifying driver fusion genes (FGs) and developing molecular targeted therapies. Kinase domain retention is a crucial factor in kinase fusion genes (KFGs), but such a systematic investigation has not been done yet. To this end, we analyzed kinase domain retention (KDR) status in chimeric protein sequences of 914 KFGs covering 312 kinases across 13 major cancer types. Based on 171 kinase domain-retained KFGs including 101 kinases, we studied their recurrence, kinase groups, fusion partners, exon-based expression depth, short DNA motifs around the break points and networks. Our results, such as more KDR than 5'-kinase fusion genes, combinatorial effects between 3'-KDR kinases and their 5'-partners and a signal transduction-specific DNA sequence motif in the break point intronic sequences, supported positive selection on 3'-kinase fusion genes in cancer. We introduced a degree-of-frequency (DoF) score to measure the possible number of KFGs of a kinase. Interestingly, kinases with high DoF scores tended to undergo strong gene expression alteration at the break points. Furthermore, our KDR gene fusion network analysis revealed six of the seven kinases with the highest DoF scores (ALK, BRAF, MET, NTRK1, NTRK3 and RET) were all observed in thyroid carcinoma. Finally, we summarized common features of 'effective' (highly recurrent) kinases in gene fusions such as expression alteration at break point, redundant usage in multiple cancer types and 3'-location tendency. Collectively, our findings are useful for prioritizing driver kinases and FGs and provided insights into KFGs' clinical implications. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. The tumor suppressor PTEN positively regulates macroautophagy by inhibiting the phosphatidylinositol 3-kinase/protein kinase B pathway

    NARCIS (Netherlands)

    Arico, S.; Petiot, A.; Bauvy, C.; Dubbelhuis, P. F.; Meijer, A. J.; Codogno, P.; Ogier-Denis, E.

    2001-01-01

    The tumor suppressor PTEN is a dual protein and phosphoinositide phosphatase that negatively controls the phosphatidylinositol (PI) 3-kinase/protein kinase B (Akt/PKB) signaling pathway. Interleukin-13 via the activation of the class I PI 3-kinase has been shown to inhibit the macroautophagic

  5. Ror receptor tyrosine kinases: orphans no more.

    Science.gov (United States)

    Green, Jennifer L; Kuntz, Steven G; Sternberg, Paul W

    2008-11-01

    Receptor tyrosine kinase-like orphan receptor (Ror) proteins are a conserved family of tyrosine kinase receptors that function in developmental processes including skeletal and neuronal development, cell movement and cell polarity. Although Ror proteins were originally named because the associated ligand and signaling pathway were unknown, recent studies in multiple species have now established that Ror proteins are Wnt receptors. Depending on the cellular context, Ror proteins can either activate or repress transcription of Wnt target genes and can modulate Wnt signaling by sequestering Wnt ligands. New evidence implicates Ror proteins in planar cell polarity, an alternative Wnt pathway. Here, we review the progress made in understanding these mysterious proteins and, in particular, we focus on their function as Wnt receptors.

  6. Phosphatidylinositol 4-kinases: Function, structure, and inhibition

    International Nuclear Information System (INIS)

    Boura, Evzen; Nencka, Radim

    2015-01-01

    The phosphatidylinositol 4-kinases (PI4Ks) synthesize phosphatidylinositol 4-phosphate (PI4P), a key member of the phosphoinositide family. PI4P defines the membranes of Golgi and trans-Golgi network (TGN) and regulates trafficking to and from the Golgi. Humans have two type II PI4Ks (α and β) and two type III enzymes (α and β). Recently, the crystal structures were solved for both type II and type III kinase revealing atomic details of their function. Importantly, the type III PI4Ks are hijacked by +RNA viruses to create so-called membranous web, an extensively phosphorylated and modified membrane system dedicated to their replication. Therefore, selective and potent inhibitors of PI4Ks have been developed as potential antiviral agents. Here we focus on the structure and function of PI4Ks and their potential in human medicine

  7. Src family kinases in chronic kidney disease.

    Science.gov (United States)

    Wang, Jun; Zhuang, Shougang

    2017-09-01

    Src family kinases (SFKs) belong to nonreceptor protein tyrosine kinases and have been implicated in the regulation of numerous cellular processes, including cell proliferation, differentiation, migration and invasion, and angiogenesis. The role and mechanisms of SFKs in tumorgenesis have been extensively investigated, and some SFK inhibitors are currently under clinical trials for tumor treatment. Recent studies have also demonstrated the importance of SFKs in regulating the development of various fibrosis-related chronic diseases (e.g., idiopathic pulmonary fibrosis, liver fibrosis, renal fibrosis, and systemic sclerosis). In this article, we summarize the roles of SFKs in various chronic kidney diseases, including glomerulonephritis, diabetic nephropathy, human immunodeficiency virus-associated nephropathy, autosomal dominant form of polycystic kidney disease, and obesity-associated kidney disease, and discuss the mechanisms involved. Copyright © 2017 the American Physiological Society.

  8. Phosphatidylinositol 4-kinases: Function, structure, and inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Boura, Evzen, E-mail: boura@uochb.cas.cz; Nencka, Radim, E-mail: nencka@uochb.cas.cz

    2015-10-01

    The phosphatidylinositol 4-kinases (PI4Ks) synthesize phosphatidylinositol 4-phosphate (PI4P), a key member of the phosphoinositide family. PI4P defines the membranes of Golgi and trans-Golgi network (TGN) and regulates trafficking to and from the Golgi. Humans have two type II PI4Ks (α and β) and two type III enzymes (α and β). Recently, the crystal structures were solved for both type II and type III kinase revealing atomic details of their function. Importantly, the type III PI4Ks are hijacked by +RNA viruses to create so-called membranous web, an extensively phosphorylated and modified membrane system dedicated to their replication. Therefore, selective and potent inhibitors of PI4Ks have been developed as potential antiviral agents. Here we focus on the structure and function of PI4Ks and their potential in human medicine.

  9. Molecular Imaging of the ATM Kinase Activity

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Terence M. [Department of Radiation Oncology, Ohio State University, Columbus, Ohio (United States); Nyati, Shyam [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Center for Molecular Imaging, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Ross, Brian D. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Rehemtulla, Alnawaz, E-mail: alnawaz@umich.edu [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Center for Molecular Imaging, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)

    2013-08-01

    Purpose: Ataxia telangiectasia mutated (ATM) is a serine/threonine kinase critical to the cellular DNA-damage response, including from DNA double-strand breaks. ATM activation results in the initiation of a complex cascade of events including DNA damage repair, cell cycle checkpoint control, and survival. We sought to create a bioluminescent reporter that dynamically and noninvasively measures ATM kinase activity in living cells and subjects. Methods and Materials: Using the split luciferase technology, we constructed a hybrid cDNA, ATM-reporter (ATMR), coding for a protein that quantitatively reports on changes in ATM kinase activity through changes in bioluminescence. Results: Treatment of ATMR-expressing cells with ATM inhibitors resulted in a dose-dependent increase in bioluminescence activity. In contrast, induction of ATM kinase activity upon irradiation resulted in a decrease in reporter activity that correlated with ATM and Chk2 activation by immunoblotting in a time-dependent fashion. Nuclear targeting improved ATMR sensitivity to both ATM inhibitors and radiation, whereas a mutant ATMR (lacking the target phosphorylation site) displayed a muted response. Treatment with ATM inhibitors and small interfering (si)RNA-targeted knockdown of ATM confirm the specificity of the reporter. Using reporter expressing xenografted tumors demonstrated the ability of ATMR to report in ATM activity in mouse models that correlated in a time-dependent fashion with changes in Chk2 activity. Conclusions: We describe the development and validation of a novel, specific, noninvasive bioluminescent reporter that enables monitoring of ATM activity in real time, in vitro and in vivo. Potential applications of this reporter include the identification and development of novel ATM inhibitors or ATM-interacting partners through high-throughput screens and in vivo pharmacokinetic/pharmacodynamic studies of ATM inhibitors in preclinical models.

  10. Phosphatidylinositol 4-kinases: Function, structure, and inhibition

    Czech Academy of Sciences Publication Activity Database

    Bouřa, Evžen; Nencka, Radim

    2015-01-01

    Roč. 337, č. 2 (2015), s. 136-145 ISSN 0014-4827 R&D Projects: GA ČR GJ15-21030Y; GA MŠk LO1302; GA ČR GA15-09310S EU Projects: European Commission(XE) 333916 - STARPI4K Institutional support: RVO:61388963 Keywords : phosphatidylinositol 4-kinase * inhibitor * crystal structure * virus Subject RIV: CC - Organic Chemistry Impact factor: 3.378, year: 2015

  11. Aurora kinase inhibitors: Progress towards the clinic

    Czech Academy of Sciences Publication Activity Database

    Kollareddy, M.; Zheleva, D.; Dzubak, P.; Brahmkshatriya, Pathik; Lepšík, Martin; Hajduch, M.

    2012-01-01

    Roč. 30, č. 6 (2012), s. 2411-2432 ISSN 0167-6997 Grant - others:GA ČR(CZ) GA301/08/1649; GA ČR(CZ) GD303/09/H048 Program:GA; GD Institutional research plan: CEZ:AV0Z40550506 Keywords : Aurora kinases * cancer * inhibitors Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.498, year: 2012

  12. Cyclin-dependent kinase suppression by WEE1 kinase protects the genome through control of replication initiation and nucleotide consumption

    DEFF Research Database (Denmark)

    Beck, Halfdan; Nähse-Kumpf, Viola; Larsen, Marie Sofie Yoo

    2012-01-01

    Activation of oncogenes or inhibition of WEE1 kinase deregulates Cyclin-dependent kinase (CDK) activity and leads to replication stress, however, the underlying mechanism is not understood. We now show that elevation of CDK activity by inhibiting WEE1 kinase rapidly increases initiation of replic...... that deregulated CDK activity, such as that occurring following inhibition of WEE1 kinase or activation of oncogenes, induces replication stress and loss of genomic integrity through increased firing of replication origins and subsequent nucleotide shortage.......Activation of oncogenes or inhibition of WEE1 kinase deregulates Cyclin-dependent kinase (CDK) activity and leads to replication stress, however, the underlying mechanism is not understood. We now show that elevation of CDK activity by inhibiting WEE1 kinase rapidly increases initiation...

  13. The Structure of Lombricine Kinase: Implications for Phosphagen Conformational Changes

    Energy Technology Data Exchange (ETDEWEB)

    Bush, D. Jeffrey; Kirillova, Olga; Clark, Shawn A.; Davulcu, Omar; Fabiola, Felcy; Xie, Qing; Somasundaram, Thayumanasamy; Ellington, W. Ross; Chapman, Michael S. (Oregon HSU); (FSU)

    2012-05-29

    Lombricine kinase is a member of the phosphagen kinase family and a homolog of creatine and arginine kinases, enzymes responsible for buffering cellular ATP levels. Structures of lombricine kinase from the marine worm Urechis caupo were determined by x-ray crystallography. One form was crystallized as a nucleotide complex, and the other was substrate-free. The two structures are similar to each other and more similar to the substrate-free forms of homologs than to the substrate-bound forms of the other phosphagen kinases. Active site specificity loop 309-317, which is disordered in substrate-free structures of homologs and is known from the NMR of arginine kinase to be inherently dynamic, is resolved in both lombricine kinase structures, providing an improved basis for understanding the loop dynamics. Phosphagen kinases undergo a segmented closing on substrate binding, but the lombricine kinase ADP complex is in the open form more typical of substrate-free homologs. Through a comparison with prior complexes of intermediate structure, a correlation was revealed between the overall enzyme conformation and the substrate interactions of His{sup 178}. Comparative modeling provides a rationale for the more relaxed specificity of these kinases, of which the natural substrates are among the largest of the phosphagen substrates.

  14. The Pim kinases: new targets for drug development.

    Science.gov (United States)

    Swords, Ronan; Kelly, Kevin; Carew, Jennifer; Nawrocki, Stefan; Mahalingam, Devalingam; Sarantopoulos, John; Bearss, David; Giles, Francis

    2011-12-01

    The three Pim kinases are a small family of serine/threonine kinases regulating several signaling pathways that are fundamental to cancer development and progression. They were first recognized as pro-viral integration sites for the Moloney Murine Leukemia virus. Unlike other kinases, they possess a hinge region which creates a unique binding pocket for ATP. Absence of a regulatory domain means that these proteins are constitutively active once transcribed. Pim kinases are critical downstream effectors of the ABL (ableson), JAK2 (janus kinase 2), and Flt-3 (FMS related tyrosine kinase 1) oncogenes and are required by them to drive tumorigenesis. Recent investigations have established that the Pim kinases function as effective inhibitors of apoptosis and when overexpressed, produce resistance to the mTOR (mammalian target of rapamycin) inhibitor, rapamycin . Overexpression of the PIM kinases has been reported in several hematological and solid tumors (PIM 1), myeloma, lymphoma, leukemia (PIM 2) and adenocarcinomas (PIM 3). As such, the Pim kinases are a very attractive target for pharmacological inhibition in cancer therapy. Novel small molecule inhibitors of the human Pim kinases have been designed and are currently undergoing preclinical evaluation.

  15. A framework for classification of prokaryotic protein kinases.

    Directory of Open Access Journals (Sweden)

    Nidhi Tyagi

    Full Text Available BACKGROUND: Overwhelming majority of the Serine/Threonine protein kinases identified by gleaning archaeal and eubacterial genomes could not be classified into any of the well known Hanks and Hunter subfamilies of protein kinases. This is owing to the development of Hanks and Hunter classification scheme based on eukaryotic protein kinases which are highly divergent from their prokaryotic homologues. A large dataset of prokaryotic Serine/Threonine protein kinases recognized from genomes of prokaryotes have been used to develop a classification framework for prokaryotic Ser/Thr protein kinases. METHODOLOGY/PRINCIPAL FINDINGS: We have used traditional sequence alignment and phylogenetic approaches and clustered the prokaryotic kinases which represent 72 subfamilies with at least 4 members in each. Such a clustering enables classification of prokaryotic Ser/Thr kinases and it can be used as a framework to classify newly identified prokaryotic Ser/Thr kinases. After series of searches in a comprehensive sequence database we recognized that 38 subfamilies of prokaryotic protein kinases are associated to a specific taxonomic level. For example 4, 6 and 3 subfamilies have been identified that are currently specific to phylum proteobacteria, cyanobacteria and actinobacteria respectively. Similarly subfamilies which are specific to an order, sub-order, class, family and genus have also been identified. In addition to these, we also identify organism-diverse subfamilies. Members of these clusters are from organisms of different taxonomic levels, such as archaea, bacteria, eukaryotes and viruses. CONCLUSION/SIGNIFICANCE: Interestingly, occurrence of several taxonomic level specific subfamilies of prokaryotic kinases contrasts with classification of eukaryotic protein kinases in which most of the popular subfamilies of eukaryotic protein kinases occur diversely in several eukaryotes. Many prokaryotic Ser/Thr kinases exhibit a wide variety of modular

  16. Ribosomal S6 Kinase Cooperates with Casein Kinase 2 to Modulate the Drosophila Circadian Molecular Oscillator

    Science.gov (United States)

    Akten, Bikem; Tangredi, Michelle M.; Jauch, Eike; Roberts, Mary A.; Ng, Fanny; Raabe, Thomas; Jackson, F. Rob

    2009-01-01

    There is a universal requirement for post-translational regulatory mechanisms in circadian clock systems. Previous work in Drosophila has identified several kinases, phosphatases and an E3 ligase that are critical for determining the nuclear translocation and/or stability of clock proteins. The present study evaluated the function of p90 ribosomal S6 kinase (RSK) in the Drosophila circadian system. In mammals, RSK1 is a light- and clock-regulated kinase known to be activated by the MAPK pathway, but there is no direct evidence that it functions as a component of the circadian system. Here, we show that Drosophila S6KII RNA displays rhythms in abundance, indicative of circadian control. Importantly, an S6KII null mutant exhibits a short-period circadian phenotype that can be rescued by expression of the wild-type gene in clock neurons, indicating a role for S6KII in the molecular oscillator. Peak PER clock protein expression is elevated in the mutant, indicative of enhanced stability, whereas per mRNA level is decreased, consistent with enhanced feedback repression. Gene reporter assays show that decreased S6KII is associated with increased PER repression. Surprisingly, we demonstrate a physical interaction between S6KII and the Casein Kinase 2 regulatory subunit (CK2β), suggesting a functional relationship between the two kinases. In support of such a relationship, there are genetic interactions between S6KII and CK2 mutations, in vivo, which indicate that CK2 activity is required for S6KII action. We propose that the two kinases cooperate within clock neurons to fine-tune circadian period, improving the precision of the clock mechanism. PMID:19144847

  17. Human endotoxemia activates p38 MAP kinase and p42/44 MAP kinase, but not c-Jun N-terminal kinase

    NARCIS (Netherlands)

    van den Blink, B.; Branger, J.; Weijer, S.; Deventer, S. H.; van der Poll, T.; Peppelenbosch, M. P.

    2001-01-01

    All three major members of the MAPK family (i.e., p38 MAPK, p42/p44 MAPK, and c-Jun N terminal kinase (JNK)) have been shown to control cellular responses to inflammation in vitro. Therefore these kinases have been designated suitable targets for anti-inflammatory therapy. However, the extent to

  18. Diacylglycerol kinase ζ regulates RhoA activation via a kinase-independent scaffolding mechanism

    DEFF Research Database (Denmark)

    Ard, Ryan; Mulatz, Kirk; Abramovici, Hanan

    2012-01-01

    , but the underlying mechanisms are unclear. Diacylglycerol kinase ζ (DGKζ), which phosphorylates diacylglycerol to yield phosphatidic acid, selectively dissociates Rac1 by stimulating PAK1-mediated phosphorylation of RhoGDI on Ser-101/174. Similarly, phosphorylation of RhoGDI on Ser-34 by protein kinase Cα (PKCα...... DGKζ functions as a scaffold to assemble a signaling complex that functions as a RhoA-selective, GDI dissociation factor. As a regulator of Rac1 and RhoA activity, DGKζ is a critical factor linking changes in lipid signaling to actin reorganization....

  19. Calcium/phospholipid-dependent protein kinase (protein kinase C) phosphorylates and activates tyrosine hydroxylase.

    OpenAIRE

    Albert, K A; Helmer-Matyjek, E; Nairn, A C; Müller, T H; Haycock, J W; Greene, L A; Goldstein, M; Greengard, P

    1984-01-01

    Protein kinase C, purified to homogeneity, was found to phosphorylate and activate tyrosine hydroxylase that had been partially purified from pheochromocytoma PC 12 cells. These actions of protein kinase C required the presence of calcium and phospholipid. This phosphorylation of tyrosine hydroxylase reduced the Km for the cofactor 6-methyltetrahydropterine from 0.45 mM to 0.11 mM, increased the Ki for dopamine from 4.2 microM to 47.5 microM, and produced no change in the Km for tyrosine. Lit...

  20. Phosphatidylinositol 3-Kinase and Protein Kinase C Contribute to the Inhibition by Interleukin 6 of Phosphoenolpyruvate Carboxykinase Gene Expression in Cultured Rat Hepatocytes

    DEFF Research Database (Denmark)

    Christ, Bruno; Yazici, Emine; Nath, Annegret

    2000-01-01

    Gluconeogenesis, hepatocytes, interleukin 6, liver, phosphoinositide 3-kinase, phosphoenolpyruvate carboxykinase......Gluconeogenesis, hepatocytes, interleukin 6, liver, phosphoinositide 3-kinase, phosphoenolpyruvate carboxykinase...

  1. The secret life of kinases: functions beyond catalysis.

    LENUS (Irish Health Repository)

    Rauch, Jens

    2011-10-28

    Abstract Protein phosphorylation participates in the regulation of all fundamental biological processes, and protein kinases have been intensively studied. However, while the focus was on catalytic activities, accumulating evidence suggests that non-catalytic properties of protein kinases are essential, and in some cases even sufficient for their functions. These non-catalytic functions include the scaffolding of protein complexes, the competition for protein interactions, allosteric effects on other enzymes, subcellular targeting, and DNA binding. This rich repertoire often is used to coordinate phosphorylation events and enhance the specificity of substrate phosphorylation, but also can adopt functions that do not rely on kinase activity. Here, we discuss such kinase independent functions of protein and lipid kinases focussing on kinases that play a role in the regulation of cell proliferation, differentiation, apoptosis, and motility.

  2. Drosophila melanogaster deoxyribonucleoside kinase activates gemcitabine

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, Wolfgang [BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby (Denmark); Mikkelsen, Nils Egil [Department of Molecular Biology, Swedish University of Agricultural Sciences, Biomedical Centre, SE-751 24 Uppsala (Sweden); Clausen, Anders Ranegaard [Cell and Organism Biology, Lund University, Soelvegatan 35, SE-22362 Lund (Sweden); Willer, Mette [ZGene A/S, Agern Alle 7, DK-2970 Horsholm (Denmark); Eklund, Hans [Department of Molecular Biology, Swedish University of Agricultural Sciences, Biomedical Centre, SE-751 24 Uppsala (Sweden); Gojkovic, Zoran [ZGene A/S, Agern Alle 7, DK-2970 Horsholm (Denmark); Piskur, Jure, E-mail: Jure.Piskur@cob.lu.se [BioCentrum-DTU, Technical University of Denmark, DK-2800 Lyngby (Denmark); Cell and Organism Biology, Lund University, Soelvegatan 35, SE-22362 Lund (Sweden)

    2009-05-01

    Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 A resolution structure of Dm-dNK in complex with gemcitabine shows that the residues Tyr70 and Arg105 play a crucial role in the firm positioning of gemcitabine by extra interactions made by the fluoride atoms. This explains why gemcitabine is a good substrate for Dm-dNK.

  3. p21-activated Kinase1(PAK1) can promote ERK activation in a kinase independent manner

    DEFF Research Database (Denmark)

    Wang, Zhipeng; Fu, Meng; Wang, Lifeng

    2013-01-01

    204) although phosphorylation of b-Raf (Ser445) and c-Raf (Ser 338) remained unchanged. Furthermore, increased activation of the PAK1 activator Rac1 induced the formation of a triple complex of Rac1, PAK1 and Mek1, independent of the kinase activity of PAK1. These data suggest that PAK1 can stimulate...

  4. A-Raf kinase is a new interacting partner of protein kinase CK2 beta subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Issinger, O G

    1997-01-01

    In a search for protein kinase CK2 beta subunit binding proteins using the two-hybrid system, more than 1000 positive clones were isolated. Beside clones for the alpha' and beta subunit of CK2, there were clones coding for a so far unknown protein, whose partial cDNA sequence was already deposited...

  5. Peptide substrates for Rho-associated kinase 2 (Rho-kinase 2/ROCK2.

    Directory of Open Access Journals (Sweden)

    Jeong-Hun Kang

    Full Text Available Peptide substrates sensitive for a certain protein kinase could be important for new-drug development and to understand the mechanism of diseases. Rho-associated kinase (Rho-kinase/ROCK is a serine/threonine kinase, and plays an important part in cardiovascular disease, migration and invasion of tumor cells, and in neurological disorders. The purpose of this study was to find substrates with high affinity and sensitivity for ROCK2. We synthesized 136 peptide substrates from protein substrates for ROCK2 with different lengths and charged peptides. Incorporation of (32P [counts per minute (CPM] for each peptide substrate was determined by the radiolabel assay using [γ-(32P]ATP. When the top five peptide substrates showing high CPMs (R4, R22, R133, R134, and R135 were phosphorylated by other enzymes (PKA, PKCα, and ERK1, R22, R133, and R135 displayed the highest CPM level for ROCK2 compared with other enzymes, whereas R4 and R134 showed similar CPM levels for ROCK2 and PKCα. We hypothesize that R22, R133, and R135 can be useful peptide substrates for ROCK2.

  6. Structures of down syndrome kinases, DYRKs, reveal mechanisms of kinase activation and substrate recognition

    DEFF Research Database (Denmark)

    Soundararajan, M.; Roos, A.K.; Savitsky, P.

    2013-01-01

    Dual-specificity tyrosine-(Y)-phosphorylation-regulated kinases (DYRKs) play key roles in brain development, regulation of splicing, and apoptosis, and are potential drug targets for neurodegenerative diseases and cancer. We present crystal structures of one representative member of each DYRK sub...

  7. A-Raf kinase is a new interacting partner of protein kinase CK2 beta subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Issinger, O G

    1997-01-01

    In a search for protein kinase CK2 beta subunit binding proteins using the two-hybrid system, more than 1000 positive clones were isolated. Beside clones for the alpha' and beta subunit of CK2, there were clones coding for a so far unknown protein, whose partial cDNA sequence was already deposite...

  8. Nuclear localization of Lyn tyrosine kinase mediated by inhibition of its kinase activity

    International Nuclear Information System (INIS)

    Ikeda, Kikuko; Nakayama, Yuji; Togashi, Yuuki; Obata, Yuuki; Kuga, Takahisa; Kasahara, Kousuke; Fukumoto, Yasunori; Yamaguchi, Naoto

    2008-01-01

    Src-family kinases, cytoplasmic enzymes that participate in various signaling events, are found at not only the plasma membrane but also subcellular compartments, such as the nucleus, the Golgi apparatus and late endosomes/lysosomes. Lyn, a member of the Src-family kinases, is known to play a role in DNA damage response and cell cycle control in the nucleus. However, it is still unclear how the localization of Lyn to the nucleus is regulated. Here, we investigated the mechanism of the distribution of Lyn between the cytoplasm and the nucleus in epitheloid HeLa cells and hematopoietic THP-1 cells. Lyn was definitely detected in purified nuclei by immunofluorescence and immunoblotting analyses. Nuclear accumulation of Lyn was enhanced upon treatment of cells with leptomycin B (LMB), an inhibitor of Crm1-mediated nuclear export. Moreover, Lyn mutants lacking the sites for lipid modification were highly accumulated in the nucleus upon LMB treatment. Intriguingly, inhibition of the kinase activity of Lyn by SU6656, Csk overexpression, or point mutation in the ATP-binding site induced an increase in nuclear Lyn levels. These results suggest that Lyn being imported into and rapidly exported from the nucleus preferentially accumulates in the nucleus by inhibition of the kinase activity and lipid modification

  9. Deoxyribonucleoside kinases: two enzyme families catalyze the same reaction

    DEFF Research Database (Denmark)

    Sandrini, Michael; Piskur, Jure

    2005-01-01

    Mammals have four deoxyribonucleoside kinases, the cytoplasmic (TK1) and mitochondrial (TK2) thymidine kinases, and the deoxycytidine (dCK) and deoxyguanosine (dGK) kinases, which salvage the precursors for nucleic acids synthesis. In addition to the native deoxyribonucleoside substrates, the kin......, the kinases can phosphorylate and thereby activate a variety of anti-cancer and antiviral prodrugs. Recently, the crystal structure of human TK1 has been solved and has revealed that enzymes with fundamentally different origins and folds catalyze similar, crucial cellular reactions....

  10. How protein kinases co-ordinate mitosis in animal cells.

    Science.gov (United States)

    Ma, Hoi Tang; Poon, Randy Y C

    2011-04-01

    Mitosis is associated with profound changes in cell physiology and a spectacular surge in protein phosphorylation. To accomplish these, a remarkably large portion of the kinome is involved in the process. In the present review, we will focus on classic mitotic kinases, such as cyclin-dependent kinases, Polo-like kinases and Aurora kinases, as well as more recently characterized players such as NIMA (never in mitosis in Aspergillus nidulans)-related kinases, Greatwall and Haspin. Together, these kinases co-ordinate the proper timing and fidelity of processes including centrosomal functions, spindle assembly and microtubule-kinetochore attachment, as well as sister chromatid separation and cytokinesis. A recurrent theme of the mitotic kinase network is the prevalence of elaborated feedback loops that ensure bistable conditions. Sequential phosphorylation and priming phosphorylation on substrates are also frequently employed. Another important concept is the role of scaffolds, such as centrosomes for protein kinases during mitosis. Elucidating the entire repertoire of mitotic kinases, their functions, regulation and interactions is critical for our understanding of normal cell growth and in diseases such as cancers.

  11. Identification of a fungi-specific lineage of protein kinases closely related to tyrosine kinases.

    Science.gov (United States)

    Zhao, Zhongtao; Jin, Qiaojun; Xu, Jin-Rong; Liu, Huiquan

    2014-01-01

    Tyrosine kinases (TKs) specifically catalyze the phosphorylation of tyrosine residues in proteins and play essential roles in many cellular processes. Although TKs mainly exist in animals, recent studies revealed that some organisms outside the Opisthokont clade also contain TKs. The fungi, as the sister group to animals, are thought to lack TKs. To better understand the origin and evolution of TKs, it is important to investigate if fungi have TK or TK-related genes. We therefore systematically identified possible TKs across the fungal kingdom by using the profile hidden Markov Models searches and phylogenetic analyses. Our results confirmed that fungi lack the orthologs of animal TKs. We identified a fungi-specific lineage of protein kinases (FslK) that appears to be a sister group closely related to TKs. Sequence analysis revealed that members of the FslK clade contain all the conserved protein kinase sub-domains and thus are likely enzymatically active. However, they lack key amino acid residues that determine TK-specific activities, indicating that they are not true TKs. Phylogenetic analysis indicated that the last common ancestor of fungi may have possessed numerous members of FslK. The ancestral FslK genes were lost in Ascomycota and Ustilaginomycotina and Pucciniomycotina of Basidiomycota during evolution. Most of these ancestral genes, however, were retained and expanded in Agaricomycetes. The discovery of the fungi-specific lineage of protein kinases closely related to TKs helps shed light on the origin and evolution of TKs and also has potential implications for the importance of these kinases in mushroom fungi.

  12. Kinase pathway dependence in primary human leukemias determined by rapid inhibitor screening

    NARCIS (Netherlands)

    J.W. Tyner (Jeffrey); W.F. Yang (Wayne); A. Bankhead III (Armand); G. Fan (Guang); L.B. Fletcher (Luke); J. Bryant (Jade); J.M. Glover (Jason); B.H. Chang (Bill); S.E. Spurgeon (Stephen); W.H. Fleming (William); T. Kovacsovics; J. Gotlib (Jason); S.T. Oh (Stephen); M.W.N. Deininger (Michael W.); C.M. Zwaan (Christian Michel); M.L. den Boer (Monique); M.M. van den Heuvel-Eibrink (Marry); T. O'Hare (Thomas); B.J. Druker (Brian); M.M. Loriaux (Marc)

    2013-01-01

    textabstractKinases are dysregulated in most cancers, but the frequency of specific kinase mutations is low, indicating a complex etiology in kinase dysregulation. Here, we report a strategy to rapidly identify functionally important kinase targets, irrespective of the etiology of kinase pathway

  13. ROR-Family Receptor Tyrosine Kinases.

    Science.gov (United States)

    Stricker, Sigmar; Rauschenberger, Verena; Schambony, Alexandra

    2017-01-01

    ROR-family receptor tyrosine kinases form a small subfamily of receptor tyrosine kinases (RTKs), characterized by a conserved, unique domain architecture. ROR RTKs are evolutionary conserved throughout the animal kingdom and act as alternative receptors and coreceptors of WNT ligands. The intracellular signaling cascades activated downstream of ROR receptors are diverse, including but not limited to ROR-Frizzled-mediated activation of planar cell polarity signaling, RTK-like signaling, and antagonistic regulation of WNT/β-Catenin signaling. In line with their diverse repertoire of signaling functions, ROR receptors are involved in the regulation of multiple processes in embryonic development such as development of the axial and paraxial mesoderm, the nervous system and the neural crest, the axial and appendicular skeleton, and the kidney. In humans, mutations in the ROR2 gene cause two distinct developmental syndromes, recessive Robinow syndrome (RRS; MIM 268310) and dominant brachydactyly type B1 (BDB1; MIM 113000). In Robinow syndrome patients and animal models, the development of multiple organs is affected, whereas BDB1 results only in shortening of the distal phalanges of fingers and toes, reflecting the diversity of functions and signaling activities of ROR-family RTKs. In this chapter, we give an overview on ROR receptor structure and function. We discuss their signaling functions and role in vertebrate embryonic development with a focus on those developmental processes that are affected by mutations in the ROR2 gene in human patients. © 2017 Elsevier Inc. All rights reserved.

  14. Targeting the Pim kinases in multiple myeloma.

    LENUS (Irish Health Repository)

    Keane, N A

    2015-07-17

    Multiple myeloma (MM) is a plasma cell malignancy that remains incurable. Novel treatment strategies to improve survival are urgently required. The Pims are a small family of serine\\/threonine kinases with increased expression across the hematological malignancies. Pim-2 shows highest expression in MM and constitutes a promising therapeutic target. It is upregulated by the bone marrow microenvironment to mediate proliferation and promote MM survival. Pim-2 also has a key role in the bone destruction typically seen in MM. Additional putative roles of the Pim kinases in MM include trafficking of malignant cells, promoting oncogenic signaling in the hypoxic bone marrow microenvironment and mediating resistance to therapy. A number of Pim inhibitors are now under development with lead compounds entering the clinic. The ATP-competitive Pim inhibitor LGH447 has recently been reported to have single agent activity in MM. It is anticipated that Pim inhibition will be of clinical benefit in combination with standard treatments and\\/or with novel drugs targeting other survival pathways in MM.

  15. Activation of oocyte phosphatidylinositol kinase by polyamines

    International Nuclear Information System (INIS)

    Allende, J.E.; Carrasco, D.; Allende, C.C.

    1987-01-01

    Membrane bound phosphatidylinositol is phosphorylated by a specific membrane enzyme to form phosphatidylinositol 4 phosphate (PIP) which in turn is again phosphorylated to generate phosphatidylinositol 4,5 biphosphate (PIPP). The regulation of phosphatidylinositol phosphorylation and hydrolysis is relevant to the possible role of inositol phosphates as second messengers of hormone action. The membranes of Xenopus laevis oocytes contain a phosphatidylinositol kinase that can generate radioactive PIP after incubation with [ 32 ATP]. The radioactive product is extracted with methanol-chloroform and isolated by thin layer chromatography. The oocyte enzyme has an app Km for ATP of 80 μM and cannot use GTP as a phosphate donor. The formation of PIP is greatly stimulated by the addition of synthetic peptides containing clusters of polylysine at concentrations 0.5 mM. A similar effect is observed with a lysine rich peptide that corresponds to the 14 amino acids of the carboxyl terminus of the Kirstein ras 2 protein and also by polyornithine. Polyarginine and histone H 1 have much lower effects. Peptides containing polylysine clusters have also been found to affect the activity of other key membrane enzymes such as protein kinases and adenylate cyclase

  16. A casein-kinase-2-related protein kinase is tightly associated with the large T antigen of simian virus 40

    DEFF Research Database (Denmark)

    Götz, C; Koenig, M G; Issinger, O G

    1995-01-01

    The simian virus 40 (SV40) large T antigen is a multifunctional protein involved in SV40 cell transformation and lytic virus infection. Some of its activities are regulated by interaction with cellular proteins and/or by phosphorylation of T antigen by various protein kinases. In this study, we...... of T antigen by the associated kinase is reduced whereas a p34cdc2-kinase-specific peptide has no influence. In addition, the T-antigen-associated protein kinase can use GTP and ATP as phosphate donors. These properties together with the observation that immunopurified T antigen can be phosphorylated...

  17. Structures of human Bruton's tyrosine kinase in active and inactive conformations suggest a mechanism of activation for TEC family kinases.

    Science.gov (United States)

    Marcotte, Douglas J; Liu, Yu-Ting; Arduini, Robert M; Hession, Catherine A; Miatkowski, Konrad; Wildes, Craig P; Cullen, Patrick F; Hong, Victor; Hopkins, Brian T; Mertsching, Elisabeth; Jenkins, Tracy J; Romanowski, Michael J; Baker, Darren P; Silvian, Laura F

    2010-03-01

    Bruton's tyrosine kinase (BTK), a member of the TEC family of kinases, plays a crucial role in B-cell maturation and mast cell activation. Although the structures of the unphosphorylated mouse BTK kinase domain and the unphosphorylated and phosphorylated kinase domains of human ITK are known, understanding the kinase selectivity profiles of BTK inhibitors has been hampered by the lack of availability of a high resolution, ligand-bound BTK structure. Here, we report the crystal structures of the human BTK kinase domain bound to either Dasatinib (BMS-354825) at 1.9 A resolution or to 4-amino-5-(4-phenoxyphenyl)-7H-pyrrolospyrimidin- 7-yl-cyclopentane at 1.6 A resolution. This data provides information relevant to the development of small molecule inhibitors targeting BTK and the TEC family of nonreceptor tyrosine kinases. Analysis of the structural differences between the TEC and Src families of kinases near the Trp-Glu-Ile motif in the N-terminal region of the kinase domain suggests a mechanism of regulation of the TEC family members.

  18. Kinome profiling of Arabidopsis using arrays of kinase consensus substrates

    Directory of Open Access Journals (Sweden)

    Pieterse Corné MJ

    2007-02-01

    Full Text Available Abstract Background Kinome profiling aims at the parallel analysis of kinase activities in a cell. Novel developed arrays containing consensus substrates for kinases are used to assess those kinase activities. The arrays described in this paper were already used to determine kinase activities in mammalian systems, but since substrates from many organisms are present we decided to test these arrays for the determination of kinase activities in the model plant species Arabidopsis thaliana. Results Kinome profiling using Arabidopsis cell extracts resulted in the labelling of many consensus peptides by kinases from the plant, indicating the usefulness of this kinome profiling tool for plants. Method development showed that fresh and frozen plant material could be used to make cell lysates containing active kinases. Dilution of the plant extract increased the signal to noise ratio and non-radioactive ATP enhances full development of spot intensities. Upon infection of Arabidopsis with an avirulent strain of the bacterial pathogen Pseudomonas syringae pv. tomato, we could detect differential kinase activities by measuring phosphorylation of consensus peptides. Conclusion We show that kinome profiling on arrays with consensus substrates can be used to monitor kinase activities in plants. In a case study we show that upon infection with avirulent P. syringae differential kinase activities can be found. The PepChip can for example be used to purify (unknown kinases that play a role in P. syringae infection. This paper shows that kinome profiling using arrays of consensus peptides is a valuable new tool to study signal-transduction in plants. It complements the available methods for genomics and proteomics research.

  19. Heart 6-phosphofructo-2-kinase activation by insulin requires PKB (protein kinase B), but not SGK3 (serum- and glucocorticoid-induced protein kinase 3).

    OpenAIRE

    Mouton, Veronique; Toussaint, Louise; Vertommen, Didier; Gueuning, Marie-Agnes; Maisin, Liliane; Havaux, Xavier; Sanchez-Canedo, Cossette; Bertrand, Luc; Dequiedt, Franck; Hemmings, Brian A; Hue, Louis; Rider, Mark H

    2010-01-01

    On the basis of transfection experiments using a dominant-negative approach, our previous studies suggested that PKB (protein kinase B) was not involved in heart PFK-2 (6-phosphofructo2-kinase) activation by insulin. Therefore we first tested whether SGK3 (serum- and glucocorticoid-induced protein kinase 3) might be involved in this effect. Treatment of recombinant heart PFK-2 with [gamma-32P]ATP and SGK3 in vitro led to PFK-2 activation and phosphorylation at Ser466 and Ser483. However, in H...

  20. Identification and functional analysis of mitogen-activated protein kinase kinase kinase (MAPKKK) genes in canola (Brassica napus L.).

    Science.gov (United States)

    Sun, Yun; Wang, Chen; Yang, Bo; Wu, Feifei; Hao, Xueyu; Liang, Wanwan; Niu, Fangfang; Yan, Jingli; Zhang, Hanfeng; Wang, Boya; Deyholos, Michael K; Jiang, Yuan-Qing

    2014-05-01

    Mitogen-activated protein kinase (MAPK) signalling cascades, consisting of three types of reversibly phosphorylated kinases (MAPKKK, MAPKK, and MAPK), are involved in important processes including plant immunity and hormone responses. The MAPKKKs comprise the largest family in the MAPK cascades, yet only a few of these genes have been associated with physiological functions, even in the model plant Arabidopsis thaliana. Canola (Brassica napus L.) is one of the most important oilseed crops in China and worldwide. To explore MAPKKK functions in biotic and abiotic stress responses in canola, 66 MAPKKK genes were identified and 28 of them were cloned. Phylogenetic analysis of these canola MAPKKKs with homologous genes from representative species classified them into three groups (A-C), comprising four MAPKKKs, seven ZIKs, and 17 Raf genes. A further 15 interaction pairs between these MAPKKKs and the downstream BnaMKKs were identified through a yeast two-hybrid assay. The interactions were further validated through bimolecular fluorescence complementation (BiFC) analysis. In addition, by quantitative real-time reverse transcription-PCR, it was further observed that some of these BnaMAPKKK genes were regulated by different hormone stimuli, abiotic stresses, or fungal pathogen treatments. Interestingly, two novel BnaMAPKKK genes, BnaMAPKKK18 and BnaMAPKKK19, which could elicit hypersensitive response (HR)-like cell death when transiently expressed in Nicotiana benthamiana leaves, were successfully identified. Moreover, it was found that BnaMAPKKK19 probably mediated cell death through BnaMKK9. Overall, the present work has laid the foundation for further characterization of this important MAPKKK gene family in canola.

  1. Preclinical validation of Aurora kinases-targeting drugs in osteosarcoma

    NARCIS (Netherlands)

    Tavanti, E.; Sero, V.; Vella, S.; Fanelli, M.; Michelacci, F.; Landuzzi, L.; Magagnoli, G.; Versteeg, R.; Picci, P.; Hattinger, C. M.; Serra, M.

    2013-01-01

    Aurora kinases are key regulators of cell cycle and represent new promising therapeutic targets in several human tumours. Biological relevance of Aurora kinase-A and -B was assessed on osteosarcoma clinical samples and by silencing these genes with specific siRNA in three human osteosarcoma cell

  2. ATR kinase regulates its attenuation via PPM1D phosphatase ...

    Indian Academy of Sciences (India)

    In eukaryotes, in response to replication stress, DNA damage response kinase, ATR is activated, whose signalling abrogationleads to cell lethality due to aberrant fork remodelling and excessive origin firing. Here we report that inhibition ofATR kinase activity specifically during replication stress recovery results in persistent ...

  3. Brd4 Shields Chromatin from ATM Kinase Signaling Storms

    OpenAIRE

    Choi, Serah; Bakkenist, Christopher J.

    2013-01-01

    Upon activation, ataxia telangiectasia mutated (ATM) kinase rapidly phosphorylates hundreds of proteins, setting off chaotic signaling storms from areas of damaged chromatin. Recent work by Kaidi and Jackson and Floyd et al. advance our knowledge of the mechanisms that initiate or limit ATM kinase signaling storms at chromatin.

  4. Purine inhibitors of protein kinases, G proteins and polymerases

    Science.gov (United States)

    Gray, Nathanael S.; Schultz, Peter; Kim, Sung-Hou; Meijer, Laurent

    2001-07-03

    The present invention relates to purine analogs that inhibit, inter alia, protein kinases, G-proteins and polymerases. In addition, the present invention relates to methods of using such purine analogs to inhibit protein kinases, G-proteins, polymerases and other cellular processes and to treat cellular proliferative diseases.

  5. dependent/calmodulin- stimulated protein kinase from moss

    Indian Academy of Sciences (India)

    Unknown

    lin-dependent protein kinase homolog; Planta 203 S91–. S97. Lu Y-T, Hidaka H and Feldman L J 1996 Characterization of a calcium/calmodulin-dependent protein kinase homolog from maize roots showing light-regulated gravitropism; Planta. 199 18–24. Mitra D and Johri M M 2000 Enhanced expression of a cal-.

  6. One for all: the receptor-associated kinase BAK1.

    NARCIS (Netherlands)

    Chinchilla, D.; Shan, L.; He, P.; Vries, de S.C.; Kemmerling, B.

    2009-01-01

    The plant receptor kinase BAK1/SERK3 has been identified as a partner of ligand-binding leucine-rich repeat receptor kinases, in particular the brassinosteroid receptor BRI1 and the immune receptor FLS2. BAK1 positively regulates BRI1 receptor function via physical interaction and

  7. Oral protein kinase c β inhibition using ruboxistaurin

    DEFF Research Database (Denmark)

    Aiello, Lloyd Paul; Vignati, Louis; Sheetz, Matthew J

    2011-01-01

    To evaluate efficacy, safety, and causes of vision loss among 813 patients (1,392 eyes) with moderately severe to very severe nonproliferative diabetic retinopathy from the Protein Kinase C β Inhibitor-Diabetic Retinopathy Study and Protein Kinase C β Inhibitor-Diabetic Retinopathy Study 2 ruboxi...

  8. Enhanced expression of a calcium-dependent protein kinase from ...

    Indian Academy of Sciences (India)

    Among the downstream targets of calcium in plants, calcium-dependent protein kinases (CDPKs) form an interesting class of kinases which are activated by calcium binding. They have been implicated in a diverse array of responses to hormonal and environmental stimuli. In order to dissect the role of CDPKs in the moss ...

  9. Role of Bruton's tyrosine kinase in B cells and malignancies

    NARCIS (Netherlands)

    Pal Singh, S. (Simar); F. Dammeijer (Floris); R.W. Hendriks (Rudi)

    2018-01-01

    textabstractBruton's tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked

  10. Enhanced expression of a calcium-dependent protein kinase

    Indian Academy of Sciences (India)

    Among the downstream targets of calcium in plants, calcium-dependent protein kinases (CDPKs) form an interesting class of kinases which are activated by calcium binding. They have been implicated in a diverse array of responses to hormonal and environmental stimuli. In order to dissect the role of CDPKs in the moss ...

  11. Enhanced expression of a calcium-dependent protein kinase from ...

    Indian Academy of Sciences (India)

    Unknown

    Calcium-dependent protein kinase; degenerate primer; Funaria hygrometrica; nutrient; polymerase chain reaction; starvation ... Among the downstream targets of calcium in plants, calcium-dependent protein kinases (CDPKs) form an inter- esting class of ..... Saunders M J and Hepler P K 1983 Calcium antagonists and.

  12. Over-expression of NAD kinase in Corynebacterium crenatum and ...

    African Journals Online (AJOL)

    Purpose: To improve the biosynthesis of L-arginine by overexpressing homologous NAD kinase (ppnk) in Corynebacterium crenatum SYPA5-5 and to study its impact in presence of high (HOS) and low oxygen supply (LOS). Methods: A recombinant plasmid (pJC1-tac-ppnK) harboring homologous NAD kinase (ppnk) was ...

  13. Molecular cloning and characterization of a novel human kinase ...

    Indian Academy of Sciences (India)

    throughput cDNA sequencing. It encodes a protein of 341 amino acids, which shows 69% identity with the human kinase CLIK1 (AAL99353), which was suggested to be the CLP-36 interacting kinase. Bioinformatics analysis suggests that the ...

  14. Creatine kinase isozyme expression in embryonic chicken heart

    NARCIS (Netherlands)

    Lamers, W. H.; Geerts, W. J.; Moorman, A. F.; Dottin, R. P.

    1989-01-01

    The distribution pattern of creatine kinase (EC 2.7.3.2) isozymes in developing chicken heart was studied by immunohistochemistry. Creatine kinase M, which is absent from adult heart, is transiently expressed between 4 and 11 days of incubation. During that period, numerous muscular cells in the

  15. Mitogen-activated protein kinase signaling in plants

    DEFF Research Database (Denmark)

    Rodriguez, Maria Cristina Suarez; Petersen, Morten; Mundy, John

    2010-01-01

    Eukaryotic mitogen-activated protein kinase (MAPK) cascades have evolved to transduce environmental and developmental signals into adaptive and programmed responses. MAPK cascades relay and amplify signals via three types of reversibly phosphorylated kinases leading to the phosphorylation of subs...... the Arabidopsis thaliana MAPKs MPK3, 4, and 6 and MAP2Ks MKK1, 2, 4, and 5. Future work needs to focus on identifying substrates of MAPKs, and on understanding how specificity is achieved among MAPK signaling pathways.......Eukaryotic mitogen-activated protein kinase (MAPK) cascades have evolved to transduce environmental and developmental signals into adaptive and programmed responses. MAPK cascades relay and amplify signals via three types of reversibly phosphorylated kinases leading to the phosphorylation...... of substrate proteins, whose altered activities mediate a wide array of responses, including changes in gene expression. Cascades may share kinase components, but their signaling specificity is maintained by spaciotemporal constraints and dynamic protein-protein interactions and by mechanisms that include...

  16. Homing in: Mechanisms of Substrate Targeting by Protein Kinases.

    Science.gov (United States)

    Miller, Chad J; Turk, Benjamin E

    2018-03-12

    Protein phosphorylation is the most common reversible post-translational modification in eukaryotes. Humans have over 500 protein kinases, of which more than a dozen are established targets for anticancer drugs. All kinases share a structurally similar catalytic domain, yet each one is uniquely positioned within signaling networks controlling essentially all aspects of cell behavior. Kinases are distinguished from one another based on their modes of regulation and their substrate repertoires. Coupling specific inputs to the proper signaling outputs requires that kinases phosphorylate a limited number of sites to the exclusion of hundreds of thousands of off-target phosphorylation sites. Here, we review recent progress in understanding mechanisms of kinase substrate specificity and how they function to shape cellular signaling networks. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Structure of the kinase domain of Gilgamesh from Drosophila melanogaster.

    Science.gov (United States)

    Han, Ni; Chen, CuiCui; Shi, Zhubing; Cheng, Dianlin

    2014-04-01

    The CK1 family kinases regulate multiple cellular aspects and play important roles in Wnt/Wingless and Hedgehog signalling. The kinase domain of Drosophila Gilgamesh isoform I (Gilgamesh-I), a homologue of human CK1-γ, was purified and crystallized. Crystals of methylated Gilgamesh-I kinase domain with a D210A mutation diffracted to 2.85 Å resolution and belonged to space group P43212, with unit-cell parameters a = b = 52.025, c = 291.727 Å. The structure of Gilgamesh-I kinase domain, which was determined by molecular replacement, has conserved catalytic elements and an active conformation. Structural comparison indicates that an extended loop between the α1 helix and the β4 strand exists in the Gilgamesh-I kinase domain. This extended loop may regulate the activity and function of Gilgamesh-I.

  18. [The role of Gilgamesh protein kinase in Drosophila melanogaster spermatogenesis].

    Science.gov (United States)

    Nerusheva, O O; Dorogova, N V; Gubanova, N V; Omel'ianchuk, L V

    2008-09-01

    The cellular function of the gilgamesh mutation (89B9-12) of casein kinase gene in Drosophila spermatogenesis was studied. It was demonstrated that the sterility resulting from this mutation is connected with the abnormalities in spermatid individualization. A phylogenetic study of the protein sequences of casein kinases 1 from various organisms was conducted. The Gilgamesh protein was shown to be phylogenetically closer to the cytoplasmic casein kinase family, represented by the YCK3, YCK2, and YCK1 proteins of Saccharomyces cerevisiae and animal gamma-casein kinases. It is known that these yeast casein kinases are involved in vesicular trafficking, which, in turn, is related in its genetic control to the cell membrane remodeling during spermatid individualization. Thus, the data of phylogenetic analysis fit well the results obtained by studying the mutation phenotype.

  19. In this issue: Tec kinases in the crosshairs.

    Science.gov (United States)

    Faris, Mary; Bot, Adrian

    2012-04-01

    Tec family kinases are the second largest family of non-receptor tyrosine kinases, of critical importance to the biology of cells derived from the bone marrow. Significant progress in this area during the last decade revealed a role for several of these kinases in inflammatory and oncologic disorders. This led to the discovery and development of molecular targeted therapies against Tec kinases, most notably to date Btk, already showing promising clinical activity in B cell lymphoma and autoimmunity. As Btk does not carry oncogenic modifications, this also establishes a novel therapeutic paradigm, based on targeting ancillary pathways recruited by the pathogenic process to become pivotal to cancer cell's biology. This issue focuses on biology and translation of Tec kinases, at the cross-roads between immunology and cancer.

  20. MAP Kinase Cascades in Plant Innate Immunity

    Directory of Open Access Journals (Sweden)

    Magnus Wohlfahrt Rasmussen

    2012-07-01

    Full Text Available Plant mitogen-activated protein kinase (MAPK cascades generally transduce extracellular stimuli into cellular responses. These stimuli include the perception of pathogen-associated molecular patterns (PAMPs by host transmembrane pattern recognition receptors (PRRs which trigger MAPK-dependent innate immune responses. In the model Arabidopsis, molecular genetic evidence implicates a number of MAPK cascade components in PAMP signaling, and in responses to immunity-related phytohormones such as ethylene, jasmonate and salicylate. In a few cases, cascade components have been directly linked to the transcription of target genes or to the regulation of phytohormone synthesis. Thus MAPKs are obvious targets for bacterial effector proteins and are likely guardees of resistance (R proteins, which mediate defense signaling in response to the action of effectors, or effector-triggered immunity (ETI. This mini-review discusses recent progress in this field with a focus on the Arabidopsis MAPKs MPK3, 4, 6 and 11 in their apparent pathways.

  1. 2-Aminopyridine-Based Mitogen-Activated Protein Kinase Kinase Kinase Kinase 4 (MAP4K4) Inhibitors: Assessment of Mechanism-Based Safety.

    Science.gov (United States)

    Dow, Robert L; Ammirati, Mark; Bagley, Scott W; Bhattacharya, Samit K; Buckbinder, Leonard; Cortes, Christian; El-Kattan, Ayman F; Ford, Kristen; Freeman, Gary B; Guimarães, Cristiano R W; Liu, Shenping; Niosi, Mark; Skoura, Athanasia; Tess, David

    2018-04-12

    Studies have linked the serine-threonine kinase MAP4K4 to the regulation of a number of biological processes and/or diseases, including diabetes, cancer, inflammation, and angiogenesis. With a majority of the members of our lead series (e.g., 1) suffering from time-dependent inhibition (TDI) of CYP3A4, we sought design avenues that would eliminate this risk. One such approach arose from the observation that carboxylic acid-based intermediates employed in our discovery efforts retained high MAP4K4 inhibitory potency and were devoid of the TDI risk. The medicinal chemistry effort that led to the discovery of this central nervous system-impaired inhibitor together with its preclinical safety profile is described.

  2. Protein kinase substrate identification on functional protein arrays

    Directory of Open Access Journals (Sweden)

    Zhou Fang

    2008-02-01

    Full Text Available Abstract Background Over the last decade, kinases have emerged as attractive therapeutic targets for a number of different diseases, and numerous high throughput screening efforts in the pharmaceutical community are directed towards discovery of compounds that regulate kinase function. The emerging utility of systems biology approaches has necessitated the development of multiplex tools suitable for proteomic-scale experiments to replace lower throughput technologies such as mass spectroscopy for the study of protein phosphorylation. Recently, a new approach for identifying substrates of protein kinases has applied the miniaturized format of functional protein arrays to characterize phosphorylation for thousands of candidate protein substrates in a single experiment. This method involves the addition of protein kinases in solution to arrays of immobilized proteins to identify substrates using highly sensitive radioactive detection and hit identification algorithms. Results To date, the factors required for optimal performance of protein array-based kinase substrate identification have not been described. In the current study, we have carried out a detailed characterization of the protein array-based method for kinase substrate identification, including an examination of the effects of time, buffer compositions, and protein concentration on the results. The protein array approach was compared to standard solution-based assays for assessing substrate phosphorylation, and a correlation of greater than 80% was observed. The results presented here demonstrate how novel substrates for protein kinases can be quickly identified from arrays containing thousands of human proteins to provide new clues to protein kinase function. In addition, a pooling-deconvolution strategy was developed and applied that enhances characterization of specific kinase-substrate relationships and decreases reagent consumption. Conclusion Functional protein microarrays are an

  3. 20(S-Protopanaxatriol inhibits release of inflammatory mediators in immunoglobulin E-mediated mast cell activation

    Directory of Open Access Journals (Sweden)

    Dae Yong Kim

    2015-07-01

    Conclusion: PPT reduces the release of inflammatory mediators via inhibiting multiple cellular signaling pathways comprising the Ca2+ influx, protein kinase C, and PLA2, which are propagated by Syk activation upon allergic stimulation of mast cells.

  4. Protein-tyrosine Phosphatase and Kinase Specificity in Regulation of SRC and Breast Tumor Kinase* ♦

    Science.gov (United States)

    Fan, Gaofeng; Aleem, Saadat; Yang, Ming; Miller, W. Todd; Tonks, Nicholas K.

    2015-01-01

    Despite significant evidence to the contrary, the view that phosphatases are “nonspecific” still pervades the field. Systems biology approaches to defining how signal transduction pathways are integrated at the level of whole organisms also often downplay the contribution of phosphatases, defining them as “erasers” that serve merely to restore the system to its basal state. Here, we present a study that counteracts the idea of “nonspecific phosphatases.” We have characterized two structurally similar and functionally related kinases, BRK and SRC, which are regulated by combinations of activating autophosphorylation and inhibitory C-terminal sites of tyrosine phosphorylation. We demonstrated specificity at the level of the kinases in that SRMS phosphorylated the C terminus of BRK, but not SRC; in contrast, CSK is the kinase responsible for C-terminal phosphorylation of SRC, but not BRK. For the phosphatases, we observed that RNAi-mediated suppression of PTP1B resulted in opposing effects on the activity of BRK and SRC and have defined the mechanisms underlying this specificity. PTP1B inhibited BRK by directly dephosphorylating the Tyr-342 autophosphorylation site. In contrast, PTP1B potentiated SRC activity, but not by dephosphorylating SRC itself directly; instead, PTP1B regulated the interaction between CBP/PAG and CSK. SRC associated with, and phosphorylated, the transmembrane protein CBP/PAG at Tyr-317, resulting in CSK recruitment. We identified PAG as a substrate of PTP1B, and dephosphorylation abolished recruitment of the inhibitory kinase CSK. Overall, these findings illustrate how the combinatorial effects of PTKs and PTPs may be integrated to regulate signaling, with both classes of enzymes displaying exquisite specificity. PMID:25897081

  5. The role of MAP2 kinases and p38 kinase in acute murine liver injury models

    Science.gov (United States)

    Zhang, Jun; Min, Robert W M; Le, Khanh; Zhou, Sheng; Aghajan, Mariam; Than, Tin A; Win, Sanda; Kaplowitz, Neil

    2017-01-01

    c-Jun N-terminal kinase (JNK) mediates hepatotoxicity through interaction of its phospho-activated form with a mitochondrial outer membrane protein, Sh3bp5 or Sab, leading to dephosphorylation of intermembrane Src and consequent impaired mitochondrial respiration and enhanced ROS release. ROS production from mitochondria activates MAP3 kinases, such as MLK3 and ASK1, which continue to activate a pathway to sustain JNK activation, and amplifies the toxic effect of acetaminophen (APAP) and TNF/galactosamine (TNF/GalN). Downstream of MAP3K, in various contexts MKK4 activates both JNK and p38 kinases and MKK7 activates only JNK. The relative role of MKK4 versus 7 in liver injury is largely unexplored, as is the potential role of p38 kinase, which might be a key mediator of toxicity in addition to JNK. Antisense oligonucleotides (ASO) to MKK4, MKK7 and p38 (versus scrambled control) were used for in vivo knockdown, and in some experiments PMH were used after in vivo knockdown. Mice were treated with APAP or TNF/GalN and injury assessed. MKK4 and MKK7 were expressed in liver and each was efficiently knocked down with two different ASOs. Massive liver injury and ALT elevation were abrogated by MKK4 but not MKK7 ASO pretreatment in both injury models. The protection was confirmed in PMH. Knockdown of MKK4 completely inhibited basal P-p38 in both cytoplasm and mitochondria. However, ALT levels and histologic injury in APAP-treated mice were not altered with p38 knockdown versus scrambled control. p38 knockdown significantly increased P-JNK levels in cytoplasm but not mitochondria after APAP treatment. In conclusion, MKK4 is the major MAP2K, which activates JNK in acute liver injury. p38, the other downstream target of MKK4, does not contribute to liver injury from APAP or TNF/galactosamine. PMID:28661486

  6. Creatine kinase and creatine kinase subunit-B in coronary sinus blood in pacing-induced angina pectoris

    DEFF Research Database (Denmark)

    Bagger, J P; Ingerslev, J; Heinsvig, E M

    1982-01-01

    In nine out of 10 patients with angiographic documented coronary artery disease, pacing-induced angina pectoris provoked myocardial production of lactate, whereas no significant release of either creatine kinase or creatine kinase subunit-B to coronary sinus and peripheral venous blood could...

  7. Transphosphorylation of E. coli proteins during production of recombinant protein kinases provides a robust system to characterize kinase specificity

    Science.gov (United States)

    Protein kinase specificity is of fundamental importance to pathway regulation and signal transduction. Here, we report a convenient system to monitor the activity and specificity of recombinant protein kinases expressed in E.coli. We apply this to the study of the cytoplasmic domain of the plant rec...

  8. Mitogen-activated protein kinases interacting kinases are autoinhibited by a reprogrammed activation segment.

    Science.gov (United States)

    Jauch, Ralf; Cho, Min-Kyu; Jäkel, Stefan; Netter, Catharina; Schreiter, Kay; Aicher, Babette; Zweckstetter, Markus; Jäckle, Herbert; Wahl, Markus C

    2006-09-06

    Autoinhibition is a recurring mode of protein kinase regulation and can be based on diverse molecular mechanisms. Here, we show by crystal structure analysis, nuclear magnetic resonance (NMR)-based nucleotide affinity studies and rational mutagenesis that nonphosphorylated mitogen-activated protein (MAP) kinases interacting kinase (Mnk) 1 is autoinhibited by conversion of the activation segment into an autoinhibitory module. In a Mnk1 crystal structure, the activation segment is repositioned via a Mnk-specific sequence insertion at the N-terminal lobe with the following consequences: (i) the peptide substrate binding site is deconstructed, (ii) the interlobal cleft is narrowed, (iii) an essential Lys-Glu pair is disrupted and (iv) the magnesium-binding loop is locked into an ATP-competitive conformation. Consistently, deletion of the Mnk-specific insertion or removal of a conserved phenylalanine side chain, which induces a blockade of the ATP pocket, increase the ATP affinity of Mnk1. Structural rearrangements required for the activation of Mnks are apparent from the cocrystal structure of a Mnk2 D228G -staurosporine complex and can be modeled on the basis of crystal packing interactions. Our data suggest a novel regulatory mechanism specific for the Mnk subfamily.

  9. The New Role for an Old Kinase: Protein Kinase CK2 Regulates Metal Ion Transport

    Directory of Open Access Journals (Sweden)

    Adam J. Johnson

    2016-12-01

    Full Text Available The pleiotropic serine/threonine protein kinase CK2 was the first kinase discovered. It is renowned for its role in cell proliferation and anti-apoptosis. The complexity of this kinase is well reflected by the findings of past decades in terms of its heterotetrameric structure, subcellular location, constitutive activity and the extensive catalogue of substrates. With the advent of non-biased high-throughput functional genomics such as genome-wide deletion mutant screening, novel aspects of CK2 functionality have been revealed. Our recent discoveries using the model organism Saccharomyces cerevisiae and mammalian cells demonstrate that CK2 regulates metal toxicity. Extensive literature search reveals that there are few but elegant works on the role of CK2 in regulating the sodium and zinc channels. As both CK2 and metal ions are key players in cell biology and oncogenesis, understanding the details of CK2’s regulation of metal ion homeostasis has a direct bearing on cancer research. In this review, we aim to garner the recent data and gain insights into the role of CK2 in metal ion transport.

  10. In vitro phosphorylation of the focal adhesion targeting domain of focal adhesion kinase by Src kinase.

    Science.gov (United States)

    Cable, Jennifer; Prutzman, Kirk; Gunawardena, Harsha P; Schaller, Michael D; Chen, Xian; Campbell, Sharon L

    2012-03-20

    Focal adhesion kinase (FAK), a key regulator of cell adhesion and migration, is overexpressed in many types of cancer. The C-terminal focal adhesion targeting (FAT) domain of FAK is necessary for proper localization of FAK to focal adhesions and subsequent activation. Phosphorylation of Y926 in the FAT domain by the tyrosine kinase Src has been shown to promote metastasis and invasion in vivo by linking the FAT domain to the MAPK pathway via its interaction with growth factor receptor-bound protein 2. Several groups have reported that inherent conformational dynamics in the FAT domain likely regulate phosphorylation of Y926; however, what regulates these dynamics is unknown. In this paper, we demonstrate that there are two sites of in vitro Src-mediated phosphorylation in the FAT domain: Y926, which has been shown to affect FAK function in vivo, and Y1008, which has no known biological role. The phosphorylation of these two tyrosine residues is pH-dependent, but this does not reflect the pH dependence of Src kinase activity. Circular dichroism and nuclear magnetic resonance data indicate that the stability and conformational dynamics of the FAT domain are sensitive to changes in pH over a physiological pH range. In particular, regions of the FAT domain previously shown to regulate phosphorylation of Y926 as well as regions near Y1008 show pH-dependent dynamics on the microsecond to millisecond time scale.

  11. The NDR kinase scaffold HYM1/MO25 is essential for MAK2 map kinase signaling in Neurospora crassa.

    Directory of Open Access Journals (Sweden)

    Anne Dettmann

    2012-09-01

    Full Text Available Cell communication is essential for eukaryotic development, but our knowledge of molecules and mechanisms required for intercellular communication is fragmentary. In particular, the connection between signal sensing and regulation of cell polarity is poorly understood. In the filamentous ascomycete Neurospora crassa, germinating spores mutually attract each other and subsequently fuse. During these tropic interactions, the two communicating cells rapidly alternate between two different physiological states, probably associated with signal delivery and response. The MAK2 MAP kinase cascade mediates cell-cell signaling. Here, we show that the conserved scaffolding protein HYM1/MO25 controls the cell shape-regulating NDR kinase module as well as the signal-receiving MAP kinase cascade. HYM1 functions as an integral part of the COT1 NDR kinase complex to regulate the interaction with its upstream kinase POD6 and thereby COT1 activity. In addition, HYM1 interacts with NRC1, MEK2, and MAK2, the three kinases of the MAK2 MAP kinase cascade, and co-localizes with MAK2 at the apex of growing cells. During cell fusion, the three kinases of the MAP kinase module as well as HYM1 are recruited to the point of cell-cell contact. hym-1 mutants phenocopy all defects observed for MAK2 pathway mutants by abolishing MAK2 activity. An NRC1-MEK2 fusion protein reconstitutes MAK2 signaling in hym-1, while constitutive activation of NRC1 and MEK2 does not. These data identify HYM1 as a novel regulator of the NRC1-MEK2-MAK2 pathway, which may coordinate NDR and MAP kinase signaling during cell polarity and intercellular communication.

  12. Arginine kinase in Phytomonas, a trypanosomatid parasite of plants.

    Science.gov (United States)

    Canepa, Gaspar E; Carrillo, Carolina; Miranda, Mariana R; Sayé, Melisa; Pereira, Claudio A

    2011-09-01

    Phytomonas are trypanosomatid plant parasites closely related to parasites that cause several human diseases. Little is known about the biology of these organisms including aspects of their metabolism. Arginine kinase (E.C. 2.7.3.3) is a phosphotransferase which catalyzes the interconversion between the phosphagen phosphoarginine and ATP. This enzyme is present in some invertebrates and is a homolog of another widely distributed phosphosphagen kinase, creatine kinase. In this work, a single canonical arginine kinase isoform was detected in Phytomonas Jma by enzymatic activity assays, PCR, and Western Blot. This arginine kinase is very similar to the canonical isoforms found in T. cruzi and T. brucei, presenting about 70% of amino acid sequence identity and a very similar molecular weight (40kDa). The Phytomonas phosphagen system seems to be very similar to T. cruzi, which has only one isoform, or T. brucei (three isoforms); establishing a difference with other trypanosomatids, such as Leishmania, which completely lacks phosphagen kinases, probably by the presence of the arginine-consuming enzyme, arginase. Finally, phylogenetic analysis suggests that Kinetoplastids' arginine kinase was acquired, during evolution, from the arthropod vectors by horizontal gene transfer. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. RhoA/Rho-Kinase in the Cardiovascular System.

    Science.gov (United States)

    Shimokawa, Hiroaki; Sunamura, Shinichiro; Satoh, Kimio

    2016-01-22

    Twenty years ago, Rho-kinase was identified as an important downstream effector of the small GTP-binding protein, RhoA. Thereafter, a series of studies demonstrated the important roles of Rho-kinase in the cardiovascular system. The RhoA/Rho-kinase pathway is now widely known to play important roles in many cellular functions, including contraction, motility, proliferation, and apoptosis, and its excessive activity induces oxidative stress and promotes the development of cardiovascular diseases. Furthermore, the important role of Rho-kinase has been demonstrated in the pathogenesis of vasospasm, arteriosclerosis, ischemia/reperfusion injury, hypertension, pulmonary hypertension, and heart failure. Cyclophilin A is secreted by vascular smooth muscle cells and inflammatory cells and activated platelets in a Rho-kinase-dependent manner, playing important roles in a wide range of cardiovascular diseases. Thus, the RhoA/Rho-kinase pathway plays crucial roles under both physiological and pathological conditions and is an important therapeutic target in cardiovascular medicine. Recently, functional differences between ROCK1 and ROCK2 have been reported in vitro. ROCK1 is specifically cleaved by caspase-3, whereas granzyme B cleaves ROCK2. However, limited information is available on the functional differences and interactions between ROCK1 and ROCK2 in the cardiovascular system in vivo. Herein, we will review the recent advances about the importance of RhoA/Rho-kinase in the cardiovascular system. © 2016 American Heart Association, Inc.

  14. Profiling bacterial kinase activity using a genetic circuit

    DEFF Research Database (Denmark)

    van der Helm, Eric; Bech, Rasmus; Lehning, Christina Eva

    subtilis kinase PtkA, transmembrane activator TkmA and the repressor FatR to construct a genetic circuit in E. coli. By tuning the repressor and kinase expression level at the same time, we were able to show a 4.2-fold increase in signal upon kinase induction. We furthermore validated that the previously...... reported FatR Y45E mutation1 attenuates operator repression. This genetic circuit provides a starting point for computational protein design and a metagenomic library-screening tool....

  15. Targeting the Synthetic Essential Kinases of Breast Cancers

    Science.gov (United States)

    2016-05-01

    kinases in mitosis and tumorigenesis. Mol Cancer Res 2007, 5(1):1-10. 12. Kufer TA, Sillje HH, Korner R, Gruss OJ, Meraldi P, Nigg EA: Human TPX2 is...AWARD NUMBER: W81XWH-15-1-0027 TITLE: Targeting the synthetic essential kinases of breast cancers PRINCIPAL INVESTIGATOR: Jen-Tsan...Targeting the synthetic essential kinases of breast cancers 5b. GRANT NUMBER W81XWH-15-1-0027 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT

  16. Second-generation inhibitors of Bruton tyrosine kinase

    Directory of Open Access Journals (Sweden)

    Jingjing Wu

    2016-09-01

    Full Text Available Abstract Bruton tyrosine kinase (BTK is a critical effector molecule for B cell development and plays a major role in lymphoma genesis. Ibrutinib is the first-generation BTK inhibitor. Ibrutinib has off-target effects on EGFR, ITK, and Tec family kinases, which explains the untoward effects of ibrutinib. Resistance to ibrutinib was also reported. The C481S mutation in the BTK kinase domain was reported to be a major mechanism of resistance to ibrutinib. This review summarizes the clinical development of novel BTK inhibitors, ACP-196 (acalabrutinib, ONO/GS-4059, and BGB-3111.

  17. Second-generation inhibitors of Bruton tyrosine kinase.

    Science.gov (United States)

    Wu, Jingjing; Liu, Christina; Tsui, Stella T; Liu, Delong

    2016-09-02

    Bruton tyrosine kinase (BTK) is a critical effector molecule for B cell development and plays a major role in lymphoma genesis. Ibrutinib is the first-generation BTK inhibitor. Ibrutinib has off-target effects on EGFR, ITK, and Tec family kinases, which explains the untoward effects of ibrutinib. Resistance to ibrutinib was also reported. The C481S mutation in the BTK kinase domain was reported to be a major mechanism of resistance to ibrutinib. This review summarizes the clinical development of novel BTK inhibitors, ACP-196 (acalabrutinib), ONO/GS-4059, and BGB-3111.

  18. Organizing signal transduction through A-kinase anchoring proteins (AKAPs).

    Science.gov (United States)

    Logue, Jeremy S; Scott, John D

    2010-11-01

    A fundamental role for protein-protein interactions in the organization of signal transduction pathways is evident. Anchoring, scaffolding and adapter proteins function to enhance the precision and directionality of these signaling events by bringing enzymes together. The cAMP signaling pathway is organized by A-kinase anchoring proteins. This family of proteins assembles enzyme complexes containing the cAMP-dependent protein kinase, phosphoprotein phosphatases, phosphodiesterases and other signaling effectors to optimize cellular responses to cAMP and other second messengers. Selected A-kinase anchoring protein signaling complexes are highlighted in this minireview. © 2010 The Authors Journal compilation © 2010 FEBS.

  19. Crystal structures of human pyridoxal kinase in complex with the neurotoxins, ginkgotoxin and theophylline: insights into pyridoxal kinase inhibition.

    Directory of Open Access Journals (Sweden)

    Amit K Gandhi

    Full Text Available Several drugs and natural compounds are known to be highly neurotoxic, triggering epileptic convulsions or seizures, and causing headaches, agitations, as well as other neuronal symptoms. The neurotoxic effects of some of these compounds, including theophylline and ginkgotoxin, have been traced to their inhibitory activity against human pyridoxal kinase (hPL kinase, resulting in deficiency of the active cofactor form of vitamin B₆, pyridoxal 5'-phosphate (PLP. Pyridoxal (PL, an inactive form of vitamin B₆ is converted to PLP by PL kinase. PLP is the B₆ vitamer required as a cofactor for over 160 enzymatic activities essential in primary and secondary metabolism. We have performed structural and kinetic studies on hPL kinase with several potential inhibitors, including ginkgotoxin and theophylline. The structural studies show ginkgotoxin and theophylline bound at the substrate site, and are involved in similar protein interactions as the natural substrate, PL. Interestingly, the phosphorylated product of ginkgotoxin is also observed bound at the active site. This work provides insights into the molecular basis of hPL kinase inhibition and may provide a working hypothesis to quickly screen or identify neurotoxic drugs as potential hPL kinase inhibitors. Such adverse effects may be prevented by administration of an appropriate form of vitamin B₆, or provide clues of how to modify these drugs to help reduce their hPL kinase inhibitory effects.

  20. ROS and CDPK-like kinase-mediated activation of MAP kinase in rice roots exposed to lead.

    Science.gov (United States)

    Huang, Tsai-Lien; Huang, Hao-Jen

    2008-04-01

    Lead (Pb2+) is a cytotoxic metal ion in plants, the mechanism of which is not yet established. The aim of this study is to investigate the signalling pathways that are activated by elevated concentrations of Pb2+ in rice roots. Root growth was stunted and cell death was accelerated when exposed to different dosages of Pb2+ during extended time periods. Using ROS-sensitive dye and Ca2+ indicator, we demonstrated that Pb2+ induced ROS production and Ca2+ accumulation, respectively. In addition, Pb2+ elicited a remarkable increase in myelin basic protein (MBP) kinase activities. By immunoblot and immunoprecipitation analysis, 40- and 42-kDa MBP kinases that were activated by Pb2+ were identified to be mitogen-activated protein (MAP) kinases. Pre-treatment of rice roots with an antioxidant and a NADPH oxidase inhibitor, glutathione (GSH) and diphenylene iodonium (DPI), effectively reduced Pb2+-induced cell death and MAP kinase activation. Moreover, calcium-dependent protein kinase (CDPK) antagonist, W7, attenuated Pb2+-induced cell death and MAP kinase activation. These results suggested that the ROS and CDPK may function in the Pb2+-triggered cell death and MAP kinase signalling pathway in rice roots.

  1. Prostate-derived sterile 20-like kinase 2 (PSK2) regulates apoptotic morphology via C-Jun N-terminal kinase and Rho kinase-1.

    Science.gov (United States)

    Zihni, Ceniz; Mitsopoulos, Costas; Tavares, Ignatius A; Ridley, Anne J; Morris, Jonathan D H

    2006-03-17

    We have reported previously that human prostate-derived sterile 20-like kinase (PSK) 1 alters actin cytoskeletal organization and binds to microtubules, regulating their organization and stability. We have shown a structurally related protein kinase PSK2, which lacks a microtubule-binding site, activated c-Jun N-terminal kinase (JNK), and induced apoptotic morphological changes that include cell contraction, membrane blebbing, and apoptotic body formation. Apoptotic stimuli increased the catalytic activity of endogenous PSK2 and JNK, and dominant negative JNK or a physiological inhibitor of JNK blocked these apoptotic morphological responses to PSK2, demonstrating a requirement for JNK. PSK2 also stimulated the cleavage of Rho kinase-1 (ROCK-I), and the activity of ROCK-I was required for PSK2 to induce cell contraction and membrane blebbing. The activation of caspases was also needed for the induction of membrane blebbing by PSK2, which was itself a substrate for caspase 3. PSK2 therefore regulates apoptotic morphology associated with the execution phase of apoptosis, which involves dynamic reorganization of the actin cytoskeleton, via downstream targets that include JNK and ROCK-I. Our findings suggest that PSKs form a subgroup of sterile 20 (STE20)-like kinases that regulate different cytoskeletal processes.

  2. Regulation of Macropinocytosis by Diacylglycerol Kinase ζ.

    Science.gov (United States)

    Ard, Ryan; Mulatz, Kirk; Pomoransky, Julia L; Parks, Robin J; Trinkle-Mulcahy, Laura; Bell, John C; Gee, Stephen H

    2015-01-01

    Macropinosomes arise from the closure of plasma membrane ruffles to bring about the non-selective uptake of nutrients and solutes into cells. The morphological changes underlying ruffle formation and macropinosome biogenesis are driven by actin cytoskeleton rearrangements under the control of the Rho GTPase Rac1. We showed previously that Rac1 is activated by diacylglycerol kinase ζ (DGKζ), which phosphorylates diacylglycerol to yield phosphatidic acid. Here, we show DGKζ is required for optimal macropinocytosis induced by growth factor stimulation of mouse embryonic fibroblasts. Time-lapse imaging of live cells and quantitative analysis revealed DGKζ was associated with membrane ruffles and nascent macropinosomes. Macropinocytosis was attenuated in DGKζ-null cells, as determined by live imaging and vaccinia virus uptake experiments. Moreover, macropinosomes that did form in DGKζ-null cells were smaller than those found in wild type cells. Rescue of this defect required DGKζ catalytic activity, consistent with it also being required for Rac1 activation. A constitutively membrane bound DGKζ mutant substantially increased the size of macropinosomes and potentiated the effect of a constitutively active Rac1 mutant on macropinocytosis. Collectively, our results suggest DGKζ functions in concert with Rac1 to regulate macropinocytosis.

  3. Targeting Sphingosine Kinase-1 To Inhibit Melanoma

    Science.gov (United States)

    Madhunapantula, SubbaRao V.; Hengst, Jeremy; Gowda, Raghavendra; Fox, Todd E.; Yun, Jong K; Robertson, Gavin P.

    2012-01-01

    SUMMARY Resistance to therapies develops rapidly for melanoma leading to more aggressive disease. Therefore, agents are needed that specifically inhibit proteins or pathways controlling the development of this disease, which can be combined, dependent on genes deregulated in a particular patient’s tumors. This study shows that elevated sphingosine-1-phosphate (S-1-P) levels resulting from increased activity of sphingosine kinase-1 (SPHK1) occur in advanced melanomas. Targeting SPHK1 using siRNA decreased anchorage dependent and independent growth as well as sensitized melanoma cells to apoptosis inducing agents. Pharmacological SPHK1 inhibitors SKI-I but not SKI-II decreased S-1-P content, elevated ceramide levels, caused a G2-M block and induced apoptotic cell death in melanomas. Targeting SPHK1 using siRNA or the pharmacological agent called SKI-I, decreased the levels of pAKT. Furthermore, SKI-I inhibited the expression of CYCLIN D1 protein and increased the activity of caspase-3/7, which in turn led to the degradation of PARP. In animals, SKI-I but not SKI-II retarded melanoma growth by 25-40%. Thus, targeting SPHK1 using siRNAs or SKI-I has therapeutic potential for melanoma treatment either alone or in combination with other targeted agents. PMID:22236408

  4. Hybrid histidine kinases in pathogenic fungi.

    Science.gov (United States)

    Defosse, Tatiana A; Sharma, Anupam; Mondal, Alok K; Dugé de Bernonville, Thomas; Latgé, Jean-Paul; Calderone, Richard; Giglioli-Guivarc'h, Nathalie; Courdavault, Vincent; Clastre, Marc; Papon, Nicolas

    2015-03-01

    Histidine kinases (HK) sense and transduce via phosphorylation events many intra- and extracellular signals in bacteria, archaea, slime moulds and plants. HK are also widespread in the fungal kingdom, but their precise roles in the regulation of physiological processes remain largely obscure. Expanding genomic resources have recently given the opportunity to identify uncharacterised HK family members in yeasts and moulds and now allow proposing a complex classification of Basidiomycota, Ascomycota and lower fungi HK. A growing number of genetic approaches have progressively provided new insight into the role of several groups of HK in prominent fungal pathogens. In particular, a series of studies have revealed that members of group III HK, which occur in the highest number of fungal species and contain a unique N-terminus region consisting of multiple HAMP domain repeats, regulate morphogenesis and virulence in various human, plant and insect pathogenic fungi. This research field is further supported by recent shape-function studies providing clear correlation between structural properties and signalling states in group III HK. Since HK are absent in mammals, these represent interesting fungal target for the discovery of new antifungal drugs. © 2015 John Wiley & Sons Ltd.

  5. Cyclin-dependent kinases in C. elegans

    Directory of Open Access Journals (Sweden)

    Boxem Mike

    2006-05-01

    Full Text Available Abstract Cell division is an inherent part of organismal development, and defects in this process can lead to developmental abnormalities as well as cancerous growth. In past decades, much of the basic cell-cycle machinery has been identified, and a major challenge in coming years will be to understand the complex interplay between cell division and multicellular development. Inevitably, this requires the use of more complex multicellular model systems. The small nematode Caenorhabditis elegans is an excellent model system to study the regulation of cell division in a multicellular organism, and is poised to make important contributions to this field. The past decade has already seen a surge in cell-cycle research in C. elegans, yielding information on the function of many basic cell-cycle regulators, and making inroads into the developmental control of cell division. This review focuses on the in vivo roles of cyclin-dependent kinases in C. elegans, and highlights novel findings implicating CDKs in coupling development to cell-cycle progression.

  6. Phylogenetic diversification of glycogen synthase kinase 3/SHAGGY-like kinase genes in plants

    Directory of Open Access Journals (Sweden)

    Soltis Pamela S

    2006-02-01

    Full Text Available Abstract Background The glycogen synthase kinase 3 (GSK3/SHAGGY-like kinases (GSKs are non-receptor serine/threonine protein kinases that are involved in a variety of biological processes. In contrast to the two members of the GSK3 family in mammals, plants appear to have a much larger set of divergent GSK genes. Plant GSKs are encoded by a multigene family; analysis of the Arabidopsis genome revealed the existence of 10 GSK genes that fall into four major groups. Here we characterized the structure of Arabidopsis and rice GSK genes and conducted the first broad phylogenetic analysis of the plant GSK gene family, covering a taxonomically diverse array of algal and land plant sequences. Results We found that the structure of GSK genes is generally conserved in Arabidopsis and rice, although we documented examples of exon expansion and intron loss. Our phylogenetic analyses of 139 sequences revealed four major clades of GSK genes that correspond to the four subgroups initially recognized in Arabidopsis. ESTs from basal angiosperms were represented in all four major clades; GSK homologs from the basal angiosperm Persea americana (avocado appeared in all four clades. Gymnosperm sequences occurred in clades I, III, and IV, and a sequence of the red alga Porphyra was sister to all green plant sequences. Conclusion Our results indicate that (1 the plant-specific GSK gene lineage was established early in the history of green plants, (2 plant GSKs began to diversify prior to the origin of extant seed plants, (3 three of the four major clades of GSKs present in Arabidopsis and rice were established early in the evolutionary history of extant seed plants, and (4 diversification into four major clades (as initially reported in Arabidopsis occurred either just prior to the origin of the angiosperms or very early in angiosperm history.

  7. A Causal Gene for Seed Dormancy on Wheat Chromosome 4A Encodes a MAP Kinase Kinase.

    Science.gov (United States)

    Torada, Atsushi; Koike, Michiya; Ogawa, Taiichi; Takenouchi, Yu; Tadamura, Kazuki; Wu, Jianzhong; Matsumoto, Takashi; Kawaura, Kanako; Ogihara, Yasunari

    2016-03-21

    Seed germination under the appropriate environmental conditions is important both for plant species survival and for successful agriculture. Seed dormancy, which controls germination time, is one of the adaptation mechanisms and domestication traits [1]. Seed dormancy is generally defined as the absence of germination of a viable seed under conditions that are favorable for germination [2]. The seed dormancy of cultivated plants has generally been reduced during domestication [3]. Bread wheat (Triticum aestivum L.) is one of the most widely grown crops in the world. Weak dormancy may be an advantage for the productivity due to uniform emergence and a disadvantage for the risks of pre-harvest sprouting (PHS), which decreases grain quality and yield [4]. A number of quantitative trait loci (QTLs) controlling natural variation of seed dormancy have been identified on various chromosomes [5]. A major QTL for seed dormancy has been consistently detected on chromosome 4A [6-13]. The QTL was designated as a major gene, Phs1, which could be precisely mapped within a 2.6 cM region [14]. Here, we identified a mitogen-activated protein kinase kinase 3 (MKK3) gene (designated TaMKK3-A) by a map-based approach as a candidate gene for the seed dormancy locus Phs1 on chromosome 4A in bread wheat. Complementation analysis showed that transformation of a dormant wheat cultivar with the TaMKK3-A allele from a nondormant cultivar clearly reduced seed dormancy. Cultivars differing in dormancy had a single nonsynonymous amino acid substitution in the kinase domain of the predicted MKK3 protein sequence, which may be associated with the length of seed dormancy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.

    Science.gov (United States)

    Nakamura, Shingo; Pourkheirandish, Mohammad; Morishige, Hiromi; Kubo, Yuta; Nakamura, Masako; Ichimura, Kazuya; Seo, Shigemi; Kanamori, Hiroyuki; Wu, Jianzhong; Ando, Tsuyu; Hensel, Goetz; Sameri, Mohammad; Stein, Nils; Sato, Kazuhiro; Matsumoto, Takashi; Yano, Masahiro; Komatsuda, Takao

    2016-03-21

    Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Bacterial Histidine Kinases as Novel Antibacterial Drug Targets

    NARCIS (Netherlands)

    Bem, A.E.; Velikova, N.R.; Pellicer, M.T.; Baarlen, van P.; Marina, A.; Wells, J.M.

    2015-01-01

    Bacterial histidine kinases (HKs) are promising targets for novel antibacterials. Bacterial HKs are part of bacterial two-component systems (TCSs), the main signal transduction pathways in bacteria, regulating various processes including virulence, secretion systems and antibiotic resistance. In

  10. Lack of the mitochondrial protein acylglycerol kinase causes Sengers syndrome.

    NARCIS (Netherlands)

    Mayr, J.A.; Haack, T.B.; Graf, E.; Zimmermann, F.A.; Wieland, T.; Haberberger, B.; Superti-Furga, A.; Kirschner, J.; Steinmann, B.; Baumgartner, M.R.; Moroni, I.; Lamantea, E.; Zeviani, M.; Rodenburg, R.J.T.; Smeitink, J.; Strom, T.M.; Meitinger, T.; Sperl, W.; Prokisch, H.

    2012-01-01

    Exome sequencing of an individual with congenital cataracts, hypertrophic cardiomyopathy, skeletal myopathy, and lactic acidosis, all typical symptoms of Sengers syndrome, discovered two nonsense mutations in the gene encoding mitochondrial acylglycerol kinase (AGK). Mutation screening of AGK in

  11. Emerging roles of protein kinases in microglia-mediated neuroinflammation.

    Science.gov (United States)

    Lee, Sun-Hwa; Suk, Kyoungho

    2017-12-15

    Neuroinflammation is mediated by resident central nervous system glia, neurons, peripherally derived immune cells, blood-brain barrier, and inflammatory mediators secreted from these cells. Neuroinflammation has been implicated in stroke and neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and amyotrophic lateral sclerosis. Protein kinases have been one of the most exploited therapeutic targets in the current pharmacological research, especially in studies on cancer and inflammation. To date, 32 small-molecule protein kinase inhibitors have been approved by the United States Food and Drug Administration for the treatment of cancer and inflammation. However, there is no drug effectively targeting neuroinflammation and/or neurodegenerative diseases. Recent studies have advanced several protein kinases as important drug targets in neuroinflammation and/or neurodegenerative diseases. Here, we review emerging protein kinases potentially involved in neuroinflammation and subsequent neurodegenerative diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Inhibitors caveolin-1 and protein kinase G show differential ...

    African Journals Online (AJOL)

    protein interactions with caveolin-1 before extracellular activating signals release it for nitric oxide (NO) production. Smooth muscle protein kinase G (PKG) is a down-stream effector of NO signaling for relaxation of vascular smooth muscle cells ...

  13. Phenotypic and molecular genetic analysis of Pyruvate Kinase ...

    African Journals Online (AJOL)

    Phenotypic and molecular genetic analysis of Pyruvate Kinase deficiency in a Tunisian family. Jaouani Mouna, Hamdi Nadia, Chaouch Leila, Kalai Miniar, Mellouli Fethi, Darragi Imen, Boudriga Imen, Chaouachi Dorra, Bejaoui Mohamed, Abbes Salem ...

  14. Adenosine monophosphate-activated protein kinase from the mud ...

    Indian Academy of Sciences (India)

    2016-12-01

    Hochachka and Somero 2002). Therefore, some animals have to initiate anaerobic metabolism to meet part of energy needs (Costanzo et al. 2004; Colson-Proch et al. 2009). Adenosine monophosphate-activated protein kinase.

  15. Protein kinase A regulatory subunit distribution in medulloblastoma

    International Nuclear Information System (INIS)

    Mucignat-Caretta, Carla; Denaro, Luca; Redaelli, Marco; D'Avella, Domenico; Caretta, Antonio

    2010-01-01

    Previous studies showed a differential distribution of the four regulatory subunits of cAMP-dependent protein kinases inside the brain, that changed in rodent gliomas: therefore, the distribution of these proteins inside the brain can give information on the functional state of the cells. Our goal was to examine human brain tumors to provide evidence for a differential distribution of protein kinase A in different tumors. The distribution of detergent insoluble regulatory (R1 and R2) and catalytic subunits of cAMP dependent kinases was examined in pediatric brain tumors by immunohistochemistry and fluorescent cAMP analogues binding. R2 is organized in large single dots in medulloblastomas, while it has a different appearance in other tumors. Fluorescent cAMP labelling was observed only in medulloblastoma. A different distribution of cAMP dependent protein kinases has been observed in medulloblastoma

  16. Localization of two mammalian cyclin dependent kinases during mammalian meiosis

    NARCIS (Netherlands)

    Ashley, T.; Walpita, D.; de rooij, D. G.

    2001-01-01

    Mammalian meiotic progression, like mitotic cell cycle progression, is regulated by cyclins and cyclin dependent kinases (CDKs). However, the unique requirements of meiosis (homologous synapsis, reciprocal recombination and the dual divisions that segregate first homologues, then sister chromatids)

  17. 21 CFR 862.1650 - Pyruvate kinase test system.

    Science.gov (United States)

    2010-04-01

    ...). Measurements obtained by this device are used in the diagnosis and treatment of various inherited anemias due to pyruvate kinase deficiency or of acute leukemias. (b) Classification. Class I (general controls...

  18. The Snf1 Protein Kinase in the Yeast Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Usaite, Renata

    2008-01-01

    . Failure in the AMPK regulatory cascade leads to metabolic disorders, such as obesity or type 2 diabetes. The knowledge about the Snf1 protein kinase remains to be of much interest in studying yeast carbon metabolism and human biology. To investigate the effect of Snf1 kinase and its regulatory subunit Snf......In yeast, Saccharomyces cerevisiae, the Snf1 protein kinase is primarily known as a key component of the glucose repression regulatory cascade. The Snf1 kinase is highly conserved among eukaryotes and its mammalian homolog AMPK is responsible for energy homeostasis in cells, organs and whole bodies...... proteome datasets (2388 proteins) to date was generated using Multidimensional Protein Identification Technology followed by quantitation using stable isotope labeling approach (chapter 3). The stable isotope labeling was compared to the spectral counting quantitative approach and the study showed...

  19. Cyclin-dependent kinase Inhibitors Inspired by Roscovitine: Purine Bioisosteres

    Czech Academy of Sciences Publication Activity Database

    Jorda, Radek; Paruch, K.; Kryštof, Vladimír

    2012-01-01

    Roč. 18, č. 20 (2012), s. 2974-2980 ISSN 1381-6128 R&D Projects: GA ČR GAP305/12/0783 Institutional research plan: CEZ:AV0Z50380511 Keywords : Cancer * cyclin-dependent kinase * inhibitor Subject RIV: ED - Physiology Impact factor: 3.311, year: 2012 http://www.benthamdirect.org/pages/article/1/3177382/cyclin-dependent-kinase-inhibitors-inspired-by-roscovitine-purine-bioisosteres.html

  20. Targeting SRC Family Kinases in HSP90 in Lung Cancer

    Science.gov (United States)

    2015-10-01

    Maryland 21702-5012 DISTRIBUTION STATEMENT: Approved for Public Release; Distribution Unlimited Targeting SRC Family Kinases and HSP90 in Lung Cancer...COVERED Annual 30 Sep 2014 - 29 Sep 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Targeting SRC Family Kinases in HSP90 in Lung Cancer 5b. GRANT...AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS Nedd9, Src , HSP90

  1. Janus Associated Kinases Inhibitors in the Pharmacological Thera

    Directory of Open Access Journals (Sweden)

    Daniela Santos1

    2017-01-01

    Full Text Available Janus associated kinases inhibitors are a new strategy for the treatment of different clinical conditions like immunologic, inflammatory and oncology disorders. The aim of this study was to perform a review of all Janus associated kinases inhibitors available in national and international pharmaceutical market, their therapeutic indications and adverse effects, and the potential indications for investigation of those already available in the pharmaceutical market. It was also performed a review of the main new Janus associated kinases inhibitors that are still in clinical research. A literature review was conducted by consulting the summary of product characteristics of Janus associated kinases inhibitors available in the pharmaceutical market and a research in the bibliographic database PubMed using the terms «JAK inhibitors», «Janus associated kinases inhibitors» and «Janus kinases inhibitors». Ninety-five publications were included in the present review, published from January 2014 to January 2015. Drug databases of the European Medicines Agency and United States Food and Drug Administration were also consulted to search for Janus associated kinases inhibitors authorized in clinical practice. Currently, ruxolitinib and tofacitinib are available in the pharmaceutical market and oclatinib is approved as a veterinary medicinal product. Both drugs approved for human use have major adverse effects at hematological and immunological levels, which enhance the importance of the pharmacist’s role in the monitoring of patients involved in these treatments. However, several molecules are in pre-clinical and clinical studies trying to prove its potential in the treatment of several immunologic, inflammatory and oncology disorders. Thus, it is still necessary to deepen the knowledge in this area in order to overcome the risks of therapy with these agents. These risks weighed against the benefits of its clinical use have compromised the progress of

  2. Expression, purification and kinase activity analysis of maize ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... Kinase activity is essential for a protein kinase to perform its biological function. In previous study we have cloned a novel plant SnRK2 subfamily gene from maize and named it as ZmSPK1. In this study the. cDNA of ZmSPK1 with dHA-His6 tag was amplified by PCR and was subcloned into the yeast.

  3. Protein kinase C signaling and cell cycle regulation

    OpenAIRE

    Black, Adrian R.; Black, Jennifer D.

    2013-01-01

    A link between T cell proliferation and the protein kinase C (PKC) family of serine/threonine kinases has been recognized for about thirty years. However, despite the wealth of information on PKC-mediated control of T cell activation, understanding of the effects of PKCs on the cell cycle machinery in this cell type remains limited. Studies in other systems have revealed important cell cycle-specific effects of PKC signaling that can either positively or negatively impact proliferation. Th...

  4. Kinase-specific prediction of protein phosphorylation sites

    DEFF Research Database (Denmark)

    Miller, Martin Lee; Blom, Nikolaj

    2009-01-01

    As extensive mass spectrometry-based mapping of the phosphoproteome progresses, computational analysis of phosphorylation-dependent signaling becomes increasingly important. The linear sequence motifs that surround phosphorylated residues have successfully been used to characterize kinase......-substrate specificity. Here, we briefly describe the available resources for predicting kinase-specific phosphorylation from sequence properties. We address the strengths and weaknesses of these resources, which are based on methods ranging from simple consensus patterns to more advanced machine-learning algorithms...

  5. Ghrelin augments murine T-cell proliferation by activation of the phosphatidylinositol-3-kinase, extracellular signal-regulated kinase and protein kinase C signaling pathways

    Science.gov (United States)

    Lee, Jun Ho; Patel, Kalpesh; Tae, Hyun Jin; Lustig, Ana; Kim, Jie Wan; Mattson, Mark P.; Taub, Dennis D.

    2014-01-01

    Thymic atrophy occurs during normal aging, and is accelerated by exposure to chronic stressors that elevate glucocorticoid levelsand impair the naïve T cell output. The orexigenic hormone ghrelin was recently shown to attenuate age-associated thymic atrophy. Here, we report that ghrelin enhances the proliferation of murine CD4+ primary T cells and a CD4+ T-cell line. Ghrelin induced activation of the ERK1/2 and Akt signaling pathways, via upstream activation of phosphatidylinositol-3-kinase and protein kinase C, to enhance T-cell proliferation. Moreover, ghrelin induced expression of the cell cycle proteins cyclin D1, cyclin E, cyclin-dependent kinase 2 (CDK2) and retinoblastoma phosphorylation. Finally, ghrelin activated the above-mentioned signaling pathways and stimulated thymocyte proliferation in young and older mice in vivo. PMID:25447526

  6. Auto-thiophosphorylation activity of Src tyrosine kinase.

    Science.gov (United States)

    Cabail, M Zulema; Chen, Emily I; Koller, Antonius; Miller, W Todd

    2016-07-07

    Intermolecular autophosphorylation at Tyr416 is a conserved mechanism of activation among the members of the Src family of nonreceptor tyrosine kinases. Like several other tyrosine kinases, Src can catalyze the thiophosphorylation of peptide and protein substrates using ATPγS as a thiophosphodonor, although the efficiency of the reaction is low. Here, we have characterized the ability of Src to auto-thiophosphorylate. Auto-thiophosphorylation of Src at Tyr416 in the activation loop proceeds efficiently in the presence of Ni(2+), resulting in kinase activation. Other tyrosine kinases (Ack1, Hck, and IGF1 receptor) also auto-thiophosphorylate in the presence of Ni(2+). Tyr416-thiophosphorylated Src is resistant to dephosphorylation by PTP1B phosphatase. Src and other tyrosine kinases catalyze auto-thiophosphorylation in the presence of Ni(2+). Thiophosphorylation of Src occurs at Tyr416 in the activation loop, and results in enhanced kinase activity. Tyr416-thiophosphorylated Src could serve as a stable, persistently-activated mimic of Src.

  7. High affinity calmodulin target sequence in the signalling molecule PI 3-kinase

    DEFF Research Database (Denmark)

    Fischer, R; Julsgart, J; Berchtold, M W

    1998-01-01

    In this study we report that phosphatidylinositol 3-kinase (PI 3-kinase), a lipid kinase which participates in downstream signalling events of heterotrimeric G protein-coupled receptors and receptor tyrosine kinases, contains a high affinity binding site for calmodulin (CaM). The putative Ca......M. Furthermore, a sequence comparison among different PI 3-kinase isoforms revealed that the sequence which can bind CaM is highly conserved within different PI 3-kinase isoforms. These results indicate a novel mechanism for regulating PI 3-kinase and provide a new direct link between Ca2+ and phospholipid...

  8. A conserved p38 MAP kinase pathway in Caenorhabditis elegans innate immunity.

    Science.gov (United States)

    Kim, Dennis H; Feinbaum, Rhonda; Alloing, Geneviève; Emerson, Fred E; Garsin, Danielle A; Inoue, Hideki; Tanaka-Hino, Miho; Hisamoto, Naoki; Matsumoto, Kunihiro; Tan, Man-Wah; Ausubel, Frederick M

    2002-07-26

    A genetic screen for Caenorhabditis elegans mutants with enhanced susceptibility to killing by Pseudomonas aeruginosa led to the identification of two genes required for pathogen resistance: sek-1, which encodes a mitogen-activated protein (MAP) kinase kinase, and nsy-1, which encodes a MAP kinase kinase kinase. RNA interference assays and biochemical analysis established that a p38 ortholog, pmk-1, functions as the downstream MAP kinase required for pathogen defense. These data suggest that this MAP kinase signaling cassette represents an ancient feature of innate immune responses in evolutionarily diverse species.

  9. Auxin efflux by PIN-FORMED proteins is activated by two different protein kinases, D6 PROTEIN KINASE and PINOID

    KAUST Repository

    Zourelidou, Melina

    2014-06-19

    The development and morphology of vascular plants is critically determined by synthesis and proper distribution of the phytohormone auxin. The directed cell-to-cell distribution of auxin is achieved through a system of auxin influx and efflux transporters. PIN-FORMED (PIN) proteins are proposed auxin efflux transporters, and auxin fluxes can seemingly be predicted based on the-in many cells-asymmetric plasma membrane distribution of PINs. Here, we show in a heterologous Xenopus oocyte system as well as in Arabidopsis thaliana inflorescence stems that PIN-mediated auxin transport is directly activated by D6 PROTEIN KINASE (D6PK) and PINOID (PID)/WAG kinases of the Arabidopsis AGCVIII kinase family. At the same time, we reveal that D6PKs and PID have differential phosphosite preferences. Our study suggests that PIN activation by protein kinases is a crucial component of auxin transport control that must be taken into account to understand auxin distribution within the plant.

  10. Protein tyrosine kinase but not protein kinase C inhibition blocks receptor induced alveolar macrophage activation

    Directory of Open Access Journals (Sweden)

    K. Pollock

    1993-01-01

    Full Text Available The selective enzyme inhibitors genistein and Ro 31-8220 were used to assess the importance of protein tyrosine kinase (PTK and protein kinase C (PKC, respectively, in N-formyl-methionyl-leucyl-phenylalanine (FMLP induced generation of superoxide anion and thromboxane B2 (TXB2 in guinea-pig alveolar macrophages (AM. Genistein (3–100 μM dose dependently inhibited FMLP (3 nM induced superoxide generation in non-primed AM and TXB2 release in non-primed or in lipopolysaccharide (LPS (10 ng/ml primed AM to a level > 80% but had litle effect up to 100 μM on phorbol myristate acetate (PMA (10 nM induced superoxide release. Ro 31-8220 inhibited PMA induced superoxide generation (IC50 0.21 ± 0.10 μM but had no effect on or potentiated (at 3 and 10 μM FMLP responses in non-primed AM. In contrast, when present during LPS priming as well as during FMLP challenge Ro 31-8220 (10 μM inhibited primed TXB2 release by > 80%. The results indicate that PTK activation is required for the generation of these inflammatory mediators by FMLP in AM. PKC activation appears to be required for LPS priming but not for transducing the FMLP signal; rather, PKC activation may modulate the signal by a negative feedback mechanism.

  11. Rapamycin Induces Mitogen-activated Protein (MAP) Kinase Phosphatase-1 (MKP-1) Expression through Activation of Protein Kinase B and Mitogen-activated Protein Kinase Kinase Pathways*

    Science.gov (United States)

    Rastogi, Ruchi; Jiang, Zhongliang; Ahmad, Nisar; Rosati, Rita; Liu, Yusen; Beuret, Laurent; Monks, Robert; Charron, Jean; Birnbaum, Morris J.; Samavati, Lobelia

    2013-01-01

    Mitogen-activated protein kinase phosphatase-1 (MKP-1), also known as dual specificity phosphatase-1 (DUSP-1), plays a crucial role in the deactivation of MAPKs. Several drugs with immune-suppressive properties modulate MKP-1 expression as part of their mechanism of action. We investigated the effect of mTOR inhibition through rapamycin and a dual mTOR inhibitor (AZD2014) on MKP-1 expression. Low dose rapamycin led to a rapid activation of both AKT and ERK pathways with a subsequent increase in MKP-1 expression. Rapamycin treatment led to phosphorylation of CREB, transcription factor 1 (ATF1), and ATF2, three transcription factors that bind to the cyclic AMP-responsive elements on the Mkp-1 promoter. Inhibition of either the MEK/ERK or the AKT pathway attenuated rapamycin-mediated MKP-1 induction. AZD2014 did not activate AKT but activated the ERK pathway, leading to a moderate MKP-1 induction. Using bone marrow-derived macrophages (BMDMs) derived from wild-type (WT) mice or mice deficient in AKT1 and AKT2 isoforms or BMDM from targeted deficiency in MEK1 and MEK2, we show that rapamycin treatment led to an increased MKP1 expression in BMDM from WT but failed to do so in BMDMs lacking the AKT1 isoform or MEK1 and MEK2. Importantly, rapamycin pretreatment inhibited LPS-mediated p38 activation and decreased nitric oxide and IL-6 production. Our work provides a conceptual framework for the observed immune modulatory effect of mTOR inhibition. PMID:24126911

  12. Structure of Human G Protein-Coupled Receptor Kinase 2 in Complex with the Kinase Inhibitor Balanol

    Energy Technology Data Exchange (ETDEWEB)

    Tesmer, John J.G.; Tesmer, Valerie M.; Lodowski, David T.; Steinhagen, Henning; Huber, Jochen (Sanofi); (Michigan); (Texas)

    2010-07-19

    G protein-coupled receptor kinase 2 (GRK2) is a pharmaceutical target for the treatment of cardiovascular diseases such as congestive heart failure, myocardial infarction, and hypertension. To better understand how nanomolar inhibition and selectivity for GRK2 might be achieved, we have determined crystal structures of human GRK2 in complex with G{beta}{gamma} in the presence and absence of the AGC kinase inhibitor balanol. The selectivity of balanol among human GRKs is assessed.

  13. Structures of Rhodopsin Kinase in Different Ligand States Reveal Key Elements Involved in G Protein-coupled Receptor Kinase Activation

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Puja; Wang, Benlian; Maeda, Tadao; Palczewski, Krzysztof; Tesmer, John J.G. (Case Western); (Michigan)

    2008-10-08

    G protein-coupled receptor (GPCR) kinases (GRKs) phosphorylate activated heptahelical receptors, leading to their uncoupling from G proteins. Here we report six crystal structures of rhodopsin kinase (GRK1), revealing not only three distinct nucleotide-binding states of a GRK but also two key structural elements believed to be involved in the recognition of activated GPCRs. The first is the C-terminal extension of the kinase domain, which was observed in all nucleotide-bound GRK1 structures. The second is residues 5-30 of the N terminus, observed in one of the GRK1{center_dot}(Mg{sup 2+}){sub 2} {center_dot}ATP structures. The N terminus was also clearly phosphorylated, leading to the identification of two novel phosphorylation sites by mass spectral analysis. Co-localization of the N terminus and the C-terminal extension near the hinge of the kinase domain suggests that activated GPCRs stimulate kinase activity by binding to this region to facilitate full closure of the kinase domain.

  14. Kinase control of latent HIV-1 infection: PIM-1 kinase as a major contributor to HIV-1 reactivation.

    Science.gov (United States)

    Duverger, Alexandra; Wolschendorf, Frank; Anderson, Joshua C; Wagner, Frederic; Bosque, Alberto; Shishido, Takao; Jones, Jennifer; Planelles, Vicente; Willey, Christopher; Cron, Randall Q; Kutsch, Olaf

    2014-01-01

    Despite the clinical relevance of latent HIV-1 infection as a block to HIV-1 eradication, the molecular biology of HIV-1 latency remains incompletely understood. We recently demonstrated the presence of a gatekeeper kinase function that controls latent HIV-1 infection. Using kinase array analysis, we here expand on this finding and demonstrate that the kinase activity profile of latently HIV-1-infected T cells is altered relative to that of uninfected T cells. A ranking of altered kinases generated from these kinome profile data predicted PIM-1 kinase as a key switch involved in HIV-1 latency control. Using genetic and pharmacologic perturbation strategies, we demonstrate that PIM-1 activity is indeed required for HIV-1 reactivation in T cell lines and primary CD4 T cells. The presented results thus confirm that kinases are key contributors to HIV-1 latency control. In addition, through mutational studies we link the inhibitory effect of PIM-1 inhibitor IV (PIMi IV) on HIV-1 reactivation to an AP-1 motif in the CD28-responsive element of the HIV-1 long terminal repeat (LTR). The results expand our conceptual understanding of the dynamic interactions of the host cell and the latent HIV-1 integration event and position kinome profiling as a research tool to reveal novel molecular mechanisms that can eventually be targeted to therapeutically trigger HIV-1 reactivation.

  15. Kinase Associated-1 Domains Drive MARK/PAR1 Kinases to Membrane Targets by Binding Acidic Phospholipids

    Energy Technology Data Exchange (ETDEWEB)

    Moravcevic, Katarina; Mendrola, Jeannine M.; Schmitz, Karl R.; Wang, Yu-Hsiu; Slochower, David; Janmey, Paul A.; Lemmon, Mark A. (UPENN-MED)

    2011-09-28

    Phospholipid-binding modules such as PH, C1, and C2 domains play crucial roles in location-dependent regulation of many protein kinases. Here, we identify the KA1 domain (kinase associated-1 domain), found at the C terminus of yeast septin-associated kinases (Kcc4p, Gin4p, and Hsl1p) and human MARK/PAR1 kinases, as a membrane association domain that binds acidic phospholipids. Membrane localization of isolated KA1 domains depends on phosphatidylserine. Using X-ray crystallography, we identified a structurally conserved binding site for anionic phospholipids in KA1 domains from Kcc4p and MARK1. Mutating this site impairs membrane association of both KA1 domains and intact proteins and reveals the importance of phosphatidylserine for bud neck localization of yeast Kcc4p. Our data suggest that KA1 domains contribute to coincidence detection, allowing kinases to bind other regulators (such as septins) only at the membrane surface. These findings have important implications for understanding MARK/PAR1 kinases, which are implicated in Alzheimer's disease, cancer, and autism.

  16. Cloning and sequence analysis of lily and tobacco guanylate kinases.

    Science.gov (United States)

    Kumar, V

    2000-03-01

    Guanylate kinase is an essential enzyme in the nucleotide biosynthetic pathway, catalyzing the reversible transfer of the terminal phosphoryl group of ATP to GMP or dGMP. This enzyme has been well studied from several organisms and many structural and functional details have been characterized. Animal GMP kinases have also been implicated in signal transduction pathways. However, the corresponding role by plant derived GMP kinases remains to be elucidated. Full-length cDNA clones encoding enzymatically active guanylate kinases were isolated from cDNA libraries of lily and tobacco. Lily cDNA is predicted to encode a 392-amino acid protein with a molecular mass of 43.1 kDa and carries amino- and carboxy- terminal extensions of the guanylate kinase (GK)-like domain. But tobacco cDNA is predicted to encode a smaller protein of 297-amino acids with a molecular mass of 32.7 kDa. The amino acid residues known to participate in the catalytic activity of functionally characterized GMP kinases, are also conserved in GK domains of LGK-1 and NGK-1. The GK domains of NGK-1, LGK-1 and previously characterized AGK-1 from Arabidopsis exhibit 74-84% identity, whereas their N- and C-terminal domains are more divergent with amino acid conservation in the order of 48-55%. Phylogenetic analysis on the deduced amino acid sequences reveals that NGK-1 and LGK-1 form one distinct subgroup along with AGK-1 and AGK-2 homologues from Arabidopsis. Isolation of GMP kinases from diverse plant species like lily and tobacco adds a new dimension in understanding their role in cell signaling pathways that are associated with plant growth and development.

  17. Thrombin generation in abdominal sepsis is Rho-kinase-dependent.

    Science.gov (United States)

    Wang, Yongzhi; Braun, Oscar Ö; Zhang, Su; Norström, Eva; Thorlacius, Henrik

    2015-05-08

    Sepsis causes severe derangements of the coagulation system. However, the signaling mechanisms regulating sepsis-induced thrombin generation remain elusive. Herein, we hypothesized that Rho-kinase might be an important regulator of thrombin generation in abdominal sepsis. Abdominal sepsis was induced by cecal ligation and puncture (CLP) in C57Bl/6 mice. Thrombin generation, coagulation factors, lung histology and myeloperoxidase (MPO) activity were determined 6 h and 24 h after induction of CLP. Induction of CLP triggered a systemic inflammatory response characterized by neutrophil accumulation and tissue injury in the lung as well as thrombocytopenia and leukocytopenia. Administration of Y-27632, a Rho-kinase inhibitor, attenuated these markers of systemic inflammation in CLP animals. Moreover, peak thrombin formation was decreased by 77% and 81% in plasma from mice 6 h and 24 h after induction of CLP. Total thrombin generation was reduced by 64% and 67% 6 h and 24 h after CLP induction, respectively. Notably, administration of Y-27632 increased peak formation by 99% and total thrombin generation by 66% in plasma from septic animals. In addition, CLP markedly decreased plasma levels of prothrombin, factor V and factor X at 6 h and 24 h. Interestingly, Rho-kinase inhibition significantly enhanced levels of prothrombin, factor V and factor X in plasma from septic mice. In addition, inhibition of Rho-kinase decreased CLP-induced elevations of CXCL2 by 36% and interleukin-6 by 38%. These novel findings suggest that sepsis-induced thrombin generation is regulated by Rho-kinase. Moreover, inhibition of Rho-kinase reverses sepsis-evoked consumption of coagulation factors. Thus, our results show that targeting Rho-kinase signaling might protect against coagulation dysfunction in abdominal sepsis. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Structural Bioinformatics and Protein Docking Analysis of the Molecular Chaperone-Kinase Interactions: Towards Allosteric Inhibition of Protein Kinases by Targeting the Hsp90-Cdc37 Chaperone Machinery

    Directory of Open Access Journals (Sweden)

    Gennady Verkhivker

    2013-11-01

    Full Text Available A fundamental role of the Hsp90-Cdc37 chaperone system in mediating maturation of protein kinase clients and supporting kinase functional activity is essential for the integrity and viability of signaling pathways involved in cell cycle control and organism development. Despite significant advances in understanding structure and function of molecular chaperones, the molecular mechanisms and guiding principles of kinase recruitment to the chaperone system are lacking quantitative characterization. Structural and thermodynamic characterization of Hsp90-Cdc37 binding with protein kinase clients by modern experimental techniques is highly challenging, owing to a transient nature of chaperone-mediated interactions. In this work, we used experimentally-guided protein docking to probe the allosteric nature of the Hsp90-Cdc37 binding with the cyclin-dependent kinase 4 (Cdk4 kinase clients. The results of docking simulations suggest that the kinase recognition and recruitment to the chaperone system may be primarily determined by Cdc37 targeting of the N-terminal kinase lobe. The interactions of Hsp90 with the C-terminal kinase lobe may provide additional “molecular brakes” that can lock (or unlock kinase from the system during client loading (release stages. The results of this study support a central role of the Cdc37 chaperone in recognition and recruitment of the kinase clients. Structural analysis may have useful implications in developing strategies for allosteric inhibition of protein kinases by targeting the Hsp90-Cdc37 chaperone machinery.

  19. Exceptional disfavor for proline at the P + 1 position among AGC and CAMK kinases establishes reciprocal specificity between them and the proline-directed kinases.

    Science.gov (United States)

    Zhu, Guozhi; Fujii, Koichi; Belkina, Natalya; Liu, Yin; James, Michael; Herrero, Juan; Shaw, Stephen

    2005-03-18

    To precisely regulate critical signaling pathways, two kinases that phosphorylate distinct sites on the same protein substrate must have mutually exclusive specificity. Evolution could assure this by designing families of kinase such as basophilic kinases and proline-directed kinase with distinct peptide specificity; their reciprocal peptide specificity would have to be very complete, since recruitment of substrate allows phosphorylation of even rather poor phosphorylation sites in a protein. Here we report a powerful evolutionary strategy that assures distinct substrates for basophilic kinases (PKA, PKG and PKC (AGC) and calmodulin-dependent protein kinase (CAMK)) and proline-directed kinase, namely by the presence or absence of proline at the P + 1 position in substrates. Analysis of degenerate and non-degenerate peptides by in vitro kinase assays reveals that proline at the P + 1 position in substrates functions as a "veto" residue in substrate recognition by AGC and CAMK kinases. Furthermore, analysis of reported substrates of two typical basophilic kinases, protein kinase C and protein kinase A, shows the lowest occurrence of proline at the P + 1 position. Analysis of crystal structures and sequence conservation provides a molecular basis for this disfavor and illustrate its generality.

  20. Overexpression of Populus trichocarpa Mitogen-Activated Protein Kinase Kinase4 Enhances Salt Tolerance in Tobacco

    Directory of Open Access Journals (Sweden)

    Chengjun Yang

    2017-10-01

    Full Text Available Mitogen-activated protein kinase (MAPK is one of the factors of cascade reactions affecting responses to signal pathway of environmental stimuli. Throughout the life of plants, MAPK family members participate in signal transduction pathways and regulate various intracellular physiological and metabolic reactions. To gain insights into regulatory function of MAPK kinase (MAPKK in Populus trichocarpa under salt stress, we obtained full-length cDNA of PtMAPKK4 and analyzed different expression levels of PtMAPKK4 gene in leaves, stems, and root organs. The relationship between PtMAPKK4 and salt stress was studied by detecting expression characteristics of mRNA under 150 mM NaCl stress using real-time quantitative polymerase chain reaction. The results showed that expression of PtMAPKK4 increased under salt (NaCl stress in leaves but initially reduced and then increased in roots. Thus, salt stress failed to induce PtMAPKK4 expression in stems. PtMAPKK4 possibly participates in regulation of plant growth and metabolism, thereby improving its salt tolerance. We used Saccharomyces cerevisiae strain INVScI to verify subcellular localization of PtMAPKK4 kinase. The yeast strains containing pYES2-PtMAPKK4-GFP plasmid expressed GFP fusion proteins under the induction of d-galactose, and the products were located in nucleus. These results were consistent with network prediction and confirmed location of PtMAPKK4 enzyme in the nucleus. We tested NaCl tolerance in transgenic tobacco lines overexpressing PtMAPKK4 under the control of 35S promoter at germination stage to detect salt tolerance function of PtMAPKK4. Compared withK326 (a wild-type tobacco, lines overexpressing PtMAPKK4 showed a certain degree of improvement in tolerance, germination, and growth. NaCl inhibited growth of overexpressed line and K326 at the seedling stage. However, statistical analysis showed longer root length, higher fresh weight, and lower MDA content in transgenic lines in

  1. Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture

    DEFF Research Database (Denmark)

    Biondi, R M; Engel, M; Sauane, M

    1996-01-01

    that in vitro protein kinase CK2 catalyzed phosphorylation of human NDPK A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated...

  2. Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture

    DEFF Research Database (Denmark)

    Biondi, R M; Engel, M; Sauane, M

    1996-01-01

    Although a number of nucleoside diphosphate kinases (NDPKs) have been reported to act as inhibitors of metastasis or as a transcription factor in mammals, it is not known whether these functions are linked to their enzymatic activity or how this protein is regulated. In this report, we show that ...

  3. The role of the C8 proton of ATP in the catalysis of shikimate kinase and adenylate kinase

    Directory of Open Access Journals (Sweden)

    Kenyon Colin P

    2012-08-01

    Full Text Available Abstract Background It has been demonstrated that the adenyl moiety of ATP plays a direct role in the regulation of ATP binding and/or phosphoryl transfer within a range of kinase and synthetase enzymes. The role of the C8-H of ATP in the binding and/or phosphoryl transfer on the enzyme activity of a number of kinase and synthetase enzymes has been elucidated. The intrinsic catalysis rate mediated by each kinase enzyme is complex, yielding apparent KM values ranging from less than 0.4 μM to more than 1 mM for ATP in the various kinases. Using a combination of ATP deuterated at the C8 position (C8D-ATP as a molecular probe with site directed mutagenesis (SDM of conserved amino acid residues in shikimate kinase and adenylate kinase active sites, we have elucidated a mechanism by which the ATP C8-H is induced to be labile in the broader kinase family. We have demonstrated the direct role of the C8-H in the rate of ATP consumption, and the direct role played by conserved Thr residues interacting with the C8-H. The mechanism by which the vast range in KM might be achieved is also suggested by these findings. Results We have demonstrated the mechanism by which the enzyme activities of Group 2 kinases, shikimate kinase (SK and adenylate kinase 1 (AK1, are controlled by the C8-H of ATP. Mutations of the conserved threonine residues associated with the labile C8-H cause the enzymes to lose their saturation kinetics over the concentration range tested. The relationship between the role C8-H of ATP in the reaction mechanism and the ATP concentration as they influence the saturation kinetics of the enzyme activity is also shown. The SDM clearly identified the amino acid residues involved in both the catalysis and regulation of phosphoryl transfer in SK and AK1 as mediated by C8H-ATP. Conclusions The data outlined serves to demonstrate the “push” mechanism associated with the control of the saturation kinetics of Group 2 kinases mediated by ATP C8-H. It

  4. Distribution of protein kinase Mzeta and the complete protein kinase C isoform family in rat brain

    DEFF Research Database (Denmark)

    Naik, M U; Benedikz, Eirikur; Hernandez, I

    2000-01-01

    Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region...... Mzeta (PKMzeta). In this study, we used immunoblot and immunocytochemical techniques with isoform-specific antisera to examine the distribution of the complete family of PKC isozymes and PKMzeta in rat brain. Each form of PKC showed a widespread distribution in the brain with a distinct regional pattern...... of high and low levels of expression. PKMzeta, the predominant form of PKM in brain, had high levels in hippocampus, frontal and occipital cortex, striatum, and hypothalamus. In the hippocampus, each isoform was expressed in a characteristic pattern, with zeta prominent in the CA1 stratum radiatum...

  5. Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases

    Energy Technology Data Exchange (ETDEWEB)

    Balajee, A.S.; Meador, J.A.; Su, Y.

    2011-03-24

    It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellular mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the

  6. Effects of obesity on protein kinase C, brain creatine kinase, transcription, and autophagy in cochlea.

    Science.gov (United States)

    Hwang, Juen-Haur

    2017-06-01

    Diet-induced obesity (DIO) has been shown to exacerbate hearing degeneration via increased hypoxia, inflammatory responses, and cell loss via both caspase-dependent and caspase-independent apoptosis signaling pathways. This study aimed to investigate the effects of DIO on the mRNA expressions of protein kinase c-β (PKC-β), brain creatine kinase (CKB), transcription modification genes, and autophagy-related genes in the cochlea of CD/1 mice. Sixteen 4-week-old male CD/1 mice were randomly divided into 2 groups. For 16 weeks, the DIO group was fed a high fat diet (60% kcal fat) and the controls were fed a standard diet. Morphometry, biochemistry, auditory brainstem response thresholds, omental fat, and histopathology of the cochlea were compared. Results showed that body weight, body length, body-mass index, omental fat, plasma triglyceride, and auditory brainstem response thresholds were significantly elevated in the DIO group compared with those of the control group. The ratio of vessel wall thickness to radius in the stria vascularis was significantly higher in the DIO group. The cell densities in the spiral ganglion, but not in the spiral prominence, of the cochlea were significantly lower in the DIO group. The expression of histone deacetylation gene 1 (HDAC1) was significantly higher in the DIO group than the control group. However, the expressions of PKC-β, CKB, HDAC3, histone acetyltransferase gene (P300), lysosome-associated membrane protein 2 (Lamp2), and light chain 3 (Lc3) genes were not significantly different between two groups. These results suggest that DIO might exacerbate hearing degeneration possibly via increased HDAC1 gene expression in the cochlea of CD/1 mice.

  7. 2-Phenylquinazolinones as dual-activity tankyrase-kinase inhibitors.

    Science.gov (United States)

    Nkizinkiko, Yves; Desantis, Jenny; Koivunen, Jarkko; Haikarainen, Teemu; Murthy, Sudarshan; Sancineto, Luca; Massari, Serena; Ianni, Federica; Obaji, Ezeogo; Loza, Maria I; Pihlajaniemi, Taina; Brea, Jose; Tabarrini, Oriana; Lehtiö, Lari

    2018-01-26

    Tankyrases (TNKSs) are enzymes specialized in catalyzing poly-ADP-ribosylation of target proteins. Several studies have validated TNKSs as anti-cancer drug targets due to their regulatory role in Wnt/β-catenin pathway. Recently a lot of effort has been put into developing more potent and selective TNKS inhibitors and optimizing them towards anti-cancer agents. We noticed that some 2-phenylquinazolinones (2-PQs) reported as CDK9 inhibitors were similar to previously published TNKS inhibitors. In this study, we profiled this series of 2-PQs against TNKS and selected kinases that are involved in the Wnt/β-catenin pathway. We found that they were much more potent TNKS inhibitors than they were CDK9/kinase inhibitors. We evaluated the compound selectivity to tankyrases over the ARTD enzyme family and solved co-crystal structures of the compounds with TNKS2. Comparative structure-based studies of the catalytic domain of TNKS2 with selected CDK9 inhibitors and docking studies of the inhibitors with two kinases (CDK9 and Akt) revealed important structural features, which could explain the selectivity of the compounds towards either tankyrases or kinases. We also discovered a compound, which was able to inhibit tankyrases, CDK9 and Akt kinases with equal µM potency.

  8. Purification and characterization of a thylakoid protein kinase

    International Nuclear Information System (INIS)

    Coughlan, S.J.; Hind, G.

    1986-01-01

    Control of state transitions in the thylakoid by reversible phosphorylation of the light-harvesting chlorophyll a/b protein complex of photosystem II (LHC-II) is modulated by a kinase. The kinase catalyzing this phosphorylation is associated with the thylakoid membrane, and is regulated by the redox state of the plastoquinone pool. The isolation and partial purification from spinach thylakoids of two protein kinases (CPK1, CPK2) of apparent molecular masses 25 kDa and 38 kDa has been reported. Neither enzyme utilizes isolated LHC-II as a substrate. The partial purification of a third protein kinase (LHCK) which can utilize both lysine-rich histones (IIIs and Vs) and isolated LHC-II as substrate has now been purified to homogeneity and characterized by SDS-polyacrylamide gel electrophoresis as a 64 kDa peptide. From a comparison of the two isolation procedures we have concluded that CPK1 is indeed a protein kinase, but has a lower specific activity than that of LHCK. 8 refs., 4 figs

  9. Intramolecular Crosstalk between Catalytic Activities of Receptor Kinases

    KAUST Repository

    Kwezi, Lusisizwe

    2018-01-22

    Signal modulation is important for the growth and development of plants and this process is mediated by a number of factors including physiological growth regulators and their associated signal transduction pathways. Protein kinases play a central role in signaling, including those involving pathogen response mechanisms. We previously demonstrated an active guanylate cyclase (GC) catalytic center in the brassinosteroid insensitive receptor (AtBRI1) within an active intracellular kinase domain resulting in dual enzymatic activity. Here we propose a novel type of receptor architecture that is characterized by a functional GC catalytic center nested in the cytosolic kinase domain enabling intramolecular crosstalk. This may be through a cGMP-AtBRI1 complex forming that may induce a negative feedback mechanism leading to desensitisation of the receptor, regulated through the cGMP production pathway. We further argue that the comparatively low but highly localized cGMP generated by the GC in response to a ligand is sufficient to modulate the kinase activity. This type of receptor therefore provides a molecular switch that directly and/or indirectly affects ligand dependent phosphorylation of downstream signaling cascades and suggests that subsequent signal transduction and modulation works in conjunction with the kinase in downstream signaling.

  10. Structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae

    Energy Technology Data Exchange (ETDEWEB)

    Michalska, Karolina [Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory (United States); Cuff, Marianne E. [Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory (United States); Structural Biology Center, Biosciences Division, Argonne National Laboratory (United States); Tesar, Christine; Feldmann, Brian [Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory (United States); Joachimiak, Andrzej, E-mail: andrzejj@anl.gov [Midwest Center for Structural Genomics, Biosciences Division, Argonne National Laboratory (United States); Structural Biology Center, Biosciences Division, Argonne National Laboratory (United States); Department of Biochemistry and Molecular Biology, University of Chicago (United States)

    2011-08-01

    The crystal structure of 2-oxo-3-deoxygalactonate kinase from the De Ley–Doudoroff pathway of galactose metabolism has been determined at 2.1 Å resolution. In most organisms, efficient d-galactose utilization requires the highly conserved Leloir pathway that converts d-galactose to d-glucose 1-phosphate. However, in some bacterial and fungal species alternative routes of d-galactose assimilation have been identified. In the so-called De Ley–Doudoroff pathway, d-galactose is metabolized into pyruvate and d-glyceraldehyde 3-phosphate in five consecutive reactions carried out by specific enzymes. The penultimate step in this pathway involves the phosphorylation of 2-oxo-3-deoxygalactonate to 2-oxo-3-deoxygalactonate 6-phosphate catalyzed by 2-oxo-3-deoxygalactonate kinase, with ATP serving as a phosphoryl-group donor. Here, a crystal structure of 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae determined at 2.1 Å resolution is reported, the first structure of an enzyme from the De Ley–Doudoroff pathway. Structural comparison indicates that the enzyme belongs to the ASKHA (acetate and sugar kinases/hsc70/actin) family of phosphotransferases. The protein is composed of two α/β domains, each of which contains a core common to all family members. Additional elements introduced between conserved structural motifs define the unique features of 2-oxo-3-deoxygalactonate kinase and possibly determine the biological function of the protein.

  11. The role of Tec family kinases in mononuclear phagocytes.

    Science.gov (United States)

    Koprulu, Afitap Derya; Ellmeier, Wilfried

    2009-01-01

    Mononuclear phagocytes, including monocytcs, macrophages, and dendritic cells, play an important role in innate and adaptive immune responses and are important regulators of the inflammatory response. Among these, monocytes/macrophages are involved in virtually all aspects of inflammation, ranging from the detection and phagocytosis of pathogens up to the resolution of inflammation and repair of tissue damage. The stimulation of cell surface receptors, such as Toll-like receptors, leads to the initiation of intracellular signal transduction pathways regulating macrophagc activation and effector functions. One group of signaling molecules stimulated on macrophage activation is formed by the Tec kinasc family, which consists of five members (Bmx, Btk, Itk, Rlk, and Tec) and constitutes the second-largest family of nonreceptor protein tyrosine kinases in the immune system. Some Tec kinases have been shown to be major regulators of antigen receptor signaling in lymphocytes, and deficiencies in Tec family kinases cause several immunological defects in humans and mice. Much less is known about the role of Tec family kinases in the myeloid branch of the hematopoietic system. In this review, we discuss the current knowledge about the role of Tec family kinases in monocytes/macrophages, in dendritic cells, and in osteoclasts.

  12. The catalytic domain of acanthamoeba myosin I heavy chain kinase. II. Expression of active catalytic domain and sequence homology to p21-activated kinase (PAK).

    Science.gov (United States)

    Brzeska, H; Szczepanowska, J; Hoey, J; Korn, E D

    1996-10-25

    Acanthamoeba myosin I heavy chain (MIHC) kinase is a monomeric 97-kDa protein that is activated by binding to acidic phospholipids or by autophosphorylation. Activation by phospholipids is inhibited by Ca2+-calmodulin. In the accompanying paper (Brzeska, H., Martin, B., and Korn, E. D. (1996) J. Biol. Chem. 271, 27049-27055), we identified the catalytic domain as the COOH-terminal 35 kDa produced by trypsin digestion of phosphorylated MIHC kinase. In this paper, we report the cloning and sequencing of the corresponding cDNA and expression of fully active catalytic domain. The expressed catalytic domain has substrate specificity similar to that of native kinase and resistance to trypsin similar to that of fully phosphorylated MIHC kinase. MIHC kinase catalytic domain has only 25% sequence identity to the catalytic domain of protein kinase A and similarly low sequence identity to the catalytic domains of protein kinase C- and calmodulin-dependent kinases, but 50% sequence identity and 70% similarity to the p21-activated kinase (PAK) and STE20 family of kinases. This suggests that MIHC kinase is (at least) evolutionarily related to the PAK family, whose activities are regulated by small GTP-binding proteins. The homology includes the presence of a potential MIHC kinase autophosphorylation site as well as conserved Tyr and Ser/Thr residues in the region corresponding to the P+1 loop of protein kinase A. A synthetic peptide corresponding to this region of MIHC kinase is phosphorylated by both the expressed catalytic domain and native MIHC kinase.

  13. Inhibiting MAP kinase activity prevents calcium transients and mitosis entry in early sea urchin embryos.

    Science.gov (United States)

    Philipova, Rada; Larman, Mark G; Leckie, Calum P; Harrison, Patrick K; Groigno, Laurence; Whitaker, Michael

    2005-07-01

    A transient calcium increase triggers nuclear envelope breakdown (mitosis entry) in sea urchin embryos. Cdk1/cyclin B kinase activation is also known to be required for mitosis entry. More recently, MAP kinase activity has also been shown to increase during mitosis. In sea urchin embryos, both kinases show a similar activation profile, peaking at the time of mitosis entry. We tested whether the activity of both kinases is required for mitosis entry and whether either kinase controls mitotic calcium signals. We found that reducing the activity of either mitotic kinase prevents nuclear envelope breakdown, despite the presence of a calcium transient, when cdk1/cyclin B kinase activity is alone inhibited. When MAP kinase activity alone was inhibited, the calcium signal was absent, suggesting that MAP kinase activity is required to generate the calcium transient that triggers nuclear envelope breakdown. However, increasing intracellular free calcium by microinjection of calcium buffers or InsP(3) while MAP kinase was inhibited did not itself induce nuclear envelope breakdown, indicating that additional MAP kinase-regulated events are necessary. After MAP kinase inhibition early in the cell cycle, the early events of the cell cycle (pronuclear migration/fusion and DNA synthesis) were unaffected, but chromosome condensation and spindle assembly are prevented. These data indicate that in sea urchin embryos, MAP kinase activity is part of a signaling complex alongside two components previously shown to be essential for entry into mitosis: the calcium transient and the increase in cdk1/cyclinB kinase activity.

  14. Cross-phosphorylation of bacterial serine/threonine and tyrosine protein kinases on key regulatory residues

    Directory of Open Access Journals (Sweden)

    Lei eShi

    2014-09-01

    Full Text Available Bacteria possess protein serine/threonine and tyrosine kinases which resemble eukaryal kinases in their capacity to phosphorylate multiple substrates. We hypothesized that the analogy might extend further, and bacterial kinases may also undergo mutual phosphorylation and activation, which is currently considered as a hallmark of eukaryal kinase networks. In order to test this hypothesis, we explored the capacity of all members of four different classes of serine/threonine and tyrosine kinases present in the firmicute model organism Bacillus subtilis to phosphorylate each other in vitro and interact with each other in vivo. The interactomics data suggested a high degree of connectivity among all types of kinases, while phosphorylation assays revealed equally wide-spread cross-phosphorylation events. Our findings suggest that the Hanks-type kinases PrkC, PrkD and YabT exhibit the highest capacity to phosphorylate other B. subtilis kinases, while the BY-kinase PtkA and the two-component-like kinases RsbW and SpoIIAB show the highest propensity to be phosphorylated by other kinases. Analysis of phosphorylated residues on several selected recipient kinases suggests that most cross-phosphorylation events concern key regulatory residues. Therefore, cross-phosphorylation events are very likely to influence the capacity of recipient kinases to phosphorylate substrates downstream in the signal transduction cascade. We therefore conclude that bacterial serine/threonine and tyrosine kinases probably engage in a network-type behavior previously described only in eukaryal cells.

  15. Substrate specificities of tyrosine-specific protein kinases toward cytoskeletal proteins in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, T.; Kadowaki, T.; Nishida, E.; Kadooka, T.; Ogawara, H.; Fukami, Y.; Sakai, H.; Takaku, F.; Kasuga, M.

    1986-11-05

    The authors have previously reported that fodrin (..beta.. subunit), tubulin (..cap alpha.. subunit) and microtubule-associated proteins (MAPs; MAP2 and tau) are good substrates for the purified insulin receptor kinase. In this study, to investigate the substrate specificities of tyrosine kinases, they have examined the actions of the purified epidermal growth factor (EGF) receptor kinase and Rous sarcoma virus src kinase on purified microfilament- and microtubule-related proteins. Among microfilament-related proteins examined, the purified EGF receptor kinase phosphorylated the ..beta.. subunit, but not the ..cap alpha.. subunit, of fodrin on tyrosine residues with a K/sub m/ below the micromolar range. The fodrin phosphorylation by the EGF receptor kinase was markedly inhibited by F-actin. In contrast, the purified src kinase preferentially phosphorylated the ..cap alpha.. subunit of fodrin on tyrosine residues. Fodrin phosphorylation by the src kinase was not inhibited by F-actin. Among microtubule proteins examined, MAP-2 was the best substrate for the EGF receptor kinase. The peptide mapping of MAP2 phosphorylated by the EGF receptor kinase and by the insulin receptor kinase produced very similar patterns of phosphopeptides, while that of MAP2 phosphorylated by the src kinase gave a distinctly different pattern. When the phosphorylation of the tubulin subunits was examined, the EGF receptor kinase preferred ..beta.. subunit to ..cap alpha.. subunit, but the src kinase phosphorylated both ..cap alpha.. and ..beta.. subunits to a similar extent. These results, together with our previous results, indicate that the substrate specificities of the EGF receptor kinase and the insulin receptor kinase are very similar, but not identical, while that of the src kinase is distinctly different from that of these growth factor receptor kinases.

  16. MAP kinase activity increases during mitosis in early sea urchin embryos.

    Science.gov (United States)

    Philipova, R; Whitaker, M

    1998-09-01

    A MBP kinase activity increases at mitosis during the first two embryonic cell cycles of the sea urchin embryo. The activity profile of the MBP kinase is the same both in whole cell extracts and after immunoprecipitation with an anti-MAP kinase antibody (2199). An in-gel assay of MBP activity also shows the same activity profile. The activity is associated with the 44 kDa protein that cross-reacts with anti-MAP kinase antibodies. The 44 kDa protein shows cross-reactivity to anti-phosphotyrosine and MAP kinase-directed anti-phosphotyrosine/phosphothreonine antibodies at the times that MBP kinase activity is high. The 2199 antibody co-precipitates some histone H1 kinase activity, but the MBP kinase activity cannot be accounted for by histone H1 kinase-dependent phosphorylation of MBP. The MAP kinase 2199 antibody was used to purify the MBP kinase activity. Peptide sequencing after partial digestion shows the protein to be homologous to MAP kinases from other species. These data demonstrate that MAP kinase activation during nuclear division is not confined to meiosis, but also occurs during mitotic cell cycles. MAP kinase activity in immunoprecipitates also increases immediately after fertilization, which in the sea urchin egg occurs at interphase of the cell cycle. Treating unfertilized eggs with the calcium ionophore A23187 stimulates the increase in MAP kinase activity, demonstrating that a calcium signal can activate MAP kinase and suggesting that the activation of MAP kinase at fertilization is due to the fertilization-induced increase in cytoplasmic free calcium concentration. This signalling pathway must differ from the pathway responsible for calcium-induced inactivation of MAP kinase activity that is found in eggs that are fertilized in meiotic metaphase.

  17. Kinase fusions are frequent in Spitz tumours and spitzoid melanomas

    Science.gov (United States)

    Wiesner, Thomas; He, Jie; Yelensky, Roman; Esteve-Puig, Rosaura; Botton, Thomas; Yeh, Iwei; Lipson, Doron; Otto, Geoff; Brennan, Kristina; Murali, Rajmohan; Garrido, Maria; Miller, Vincent A.; Ross, Jeffrey S.; Berger, Michael F.; Sparatta, Alyssa; Palmedo, Gabriele; Cerroni, Lorenzo; Busam, Klaus J.; Kutzner, Heinz; Cronin, Maureen T.; Stephens, Philip J.; Bastian, Boris C.

    2014-01-01

    Spitzoid neoplasms are a group of melanocytic tumours with distinctive histopathological features. They include benign tumours (Spitz naevi), malignant tumours (spitzoid melanomas) and tumours with borderline histopathological features and uncertain clinical outcome (atypical Spitz tumours). Their genetic underpinnings are poorly understood, and alterations in common melanoma-associated oncogenes are typically absent. Here we show that spitzoid neoplasms harbour kinase fusions of ROS1 (17%), NTRK1 (16%), ALK (10%), BRAF (5%) and RET (3%) in a mutually exclusive pattern. The chimeric proteins are constitutively active, stimulate oncogenic signalling pathways, are tumourigenic and are found in the entire biologic spectrum of spitzoid neoplasms, including 55% of Spitz naevi, 56% of atypical Spitz tumours and 39% of spitzoid melanomas. Kinase inhibitors suppress the oncogenic signalling of the fusion proteins in vitro. In summary, kinase fusions account for the majority of oncogenic aberrations in spitzoid neoplasms and may serve as therapeutic targets for metastatic spitzoid melanomas.

  18. Tyrosine phosphorylation of Rab7 by Src kinase.

    Science.gov (United States)

    Lin, Xiaosi; Zhang, Jiaming; Chen, Lingqiu; Chen, Yongjun; Xu, Xiaohui; Hong, Wanjin; Wang, Tuanlao

    2017-07-01

    The small molecular weight GTPase Rab7 is a key regulator for late endosomal/lysosomal membrane trafficking, it was known that Rab7 is phosphorylated, but the corresponding kinase and the functional regulation of Rab7 phosphorylation remain unclear. We provide evidence here that Rab7 is a substrate of Src kinase, and is tyrosine-phosphorylated by Src, withY183 residue of Rab7 being the optimal phosphorylation site for Src. Further investigations demonstrated that the tyrosine phosphorylation of Rab7 depends on the guanine nucleotide binding activity of Rab7 and the activity of Src kinase. The tyrosine phosphorylation of Rab7 is physiologically induced by EGF, and impairs the interaction of Rab7 with RILP, consequently inhibiting EGFR degradation and sustaining Akt signaling. These results suggest that the tyrosine phosphorylation of Rab7 may be involved in coordinating membrane trafficking and cell signaling. Copyright © 2017. Published by Elsevier Inc.

  19. Mutation Study of Two Thymidine Kinases 

    DEFF Research Database (Denmark)

    Skovgaard, Tine; Munch-Petersen, Birgitte; Eklund, Hans

    that phosphorylates all the natural deoxyribonucleosides and like insects, C. elegans only contains a single deoxyribonucleoside kinase-like gene. In contrast to the insects, however, the protein encoded by the elegans gene is 46 % identical to human TK1 (HuTK1) and have no homology to the insect kinase. Like HuTK1...... the C. elegans kinase (CeTK1) has thymidine as the preferred substrate, but it also displays activity with deoxyguanosine, though with high Km. A number of point mutations have been introduced in the active site of both the human and elegans TK's in order to change the substrate specificity away from...... not phosphorylate the anticancer analog 1-β-D-arabinofuranosylcytosine (AraC), however. The HuTK1 mutant has been crystallized, and azidothymidine monophosphate has been modelled into the active site....

  20. Pyrrolo[2,3-d]Pyrimidines as Kinase Inhibitors.

    Science.gov (United States)

    Musumeci, Francesca; Sanna, Monica; Grossi, Giancarlo; Brullo, Chiara; Fallacara, Anna Lucia; Schenone, Silvia

    2017-01-01

    The pyrrolo[2,3-d]pyrimidine nucleus is a deaza-isostere of adenine, the nitrogenous base of ATP, and is present in many ATP-competitive inhibitors of different kinases. In the last few years the number of articles and patents that have appeared involving this type of inhibitors has dramatically increased and some compounds have been approved for the treatment of inflammatory or myeloproliferative diseases. Other derivatives are currently being evaluated in clinical trials. This review deals with pyrrolo[2,3- d]pyrimidine derivatives active as kinase inhibitors that have been reported in the literature from 2011 to 2016, with a particular interest on the recently patented compounds. The molecules are classified depending on the inhibited kinase, focusing on their chemical structures. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. RhoA/Rho kinase in spinal cord injury

    Directory of Open Access Journals (Sweden)

    Xiangbing Wu

    2016-01-01

    Full Text Available A spinal cord injury refers to an injury to the spinal cord that is caused by a trauma instead of diseases. Spinal cord injury includes a primary mechanical injury and a much more complex secondary injury process involving inflammation, oxidation, excitotoxicity, and cell death. During the secondary injury, many signal pathways are activated and play important roles in mediating the pathogenesis of spinal cord injury. Among them, the RhoA/Rho kinase pathway plays a particular role in mediating spinal degeneration and regeneration. In this review, we will discuss the role and mechanism of RhoA/Rho kinase-mediated spinal cord pathogenesis, as well as the potential of targeting RhoA/Rho kinase as a strategy for promoting both neuroprotection and axonal regeneration.

  2. Novel Bruton's tyrosine kinase inhibitors currently in development

    Directory of Open Access Journals (Sweden)

    D'Cruz OJ

    2013-03-01

    Full Text Available Osmond J D'Cruz,1 Fatih M Uckun1,21Children's Center for Cancer and Blood Diseases, Children's Hospital Los Angeles, Los Angeles, CA, USA; 2Department of Pediatrics, University of Southern California, Los Angeles, CA, USAAbstract: Bruton's tyrosine kinase (Btk is intimately involved in multiple signal-transduction pathways regulating survival, activation, proliferation, and differentiation of B-lineage lymphoid cells. Btk is overexpressed and constitutively active in several B-lineage lymphoid malignancies. Btk has emerged as a new antiapoptotic molecular target for treatment of B-lineage leukemias and lymphomas. Preclinical and early clinical results indicate that Btk inhibitors may be useful in the treatment of leukemias and lymphomas.Keywords: tyrosine kinase, personalized therapy, kinase inhibitors, Btk, leukemia, lymphoma

  3. Structural Basis for Autoinhibition of c-Abl Tyrosine Kinase

    Energy Technology Data Exchange (ETDEWEB)

    Nagar, Bhushan; Hantschel, Oliver; Young, Matthew A.; Scheffzek,Klaus; Veach, Darren; Bornmann, William; Clarkson, Bayard; Superti-Furga,Giulio; Kuriyan, John

    2003-03-21

    c-Abl is normally regulated by an autoinhibitory mechanism, the disruption of which leads to chronic myelogenous leukemia. The details of this mechanism have been elusive because c-Abl lacks aphosphotyrosine residue that triggers the assembly of the autoinhibited form of the closely related Src kinases by internally engaging the SH2 domain. Crystal structures of c-Abl show that the N-terminal myristoyl modification of c-Abl 1b binds to the kinase domain and induces conformational changes that allow the SH2 and SH3 domains to dock onto it. Autoinhibited c-Abl forms an assembly that is strikingly similar to that of inactive Src kinases but with specific differences that explain the differential ability of the drug STI-571/Gleevec/imatinib (STI-571)to inhibit the catalytic activity of Abl, but not that of c-Src.

  4. Intramolecular Conformational Changes Optimize Protein Kinase C Signaling#

    Science.gov (United States)

    Antal, Corina E.; Violin, Jonathan D.; Kunkel, Maya T.; Skovsø, Søs

    2014-01-01

    Summary Optimal tuning of enzyme signaling is critical for cellular homeostasis. We use fluorescence resonance energy transfer reporters in live cells to follow conformational transitions that tune the affinity of a multi-domain signal transducer, protein kinase C, for optimal response to second messengers. This enzyme comprises two diacylglycerol sensors, the C1A and C1B domains, whose intrinsic affinity for ligand is sufficiently high that the enzyme would be in a ligand-engaged, active state if not for mechanisms that mask its domains. We show that both diacylglycerol sensors are exposed in newly-synthesized protein kinase C and that conformational transitions following priming phosphorylations mask the domains such that the lower affinity sensor, the C1B domain, is the primary diacylglycerol binder. Protein kinase C's conformational rearrangements serve as a paradigm for how multi-module transducers optimize their dynamic range of signaling. PMID:24631122

  5. Early emergence of negative regulation of the tyrosine kinase Src by the C-terminal Src kinase.

    Science.gov (United States)

    Taskinen, Barbara; Ferrada, Evandro; Fowler, Douglas M

    2017-11-10

    Stringent regulation of tyrosine kinase activity is essential for normal cellular function. In humans, the tyrosine kinase Src is inhibited via phosphorylation of its C-terminal tail by another kinase, C-terminal Src kinase (Csk). Although Src and Csk orthologs are present across holozoan organisms, including animals and protists, the Csk-Src negative regulatory mechanism appears to have evolved gradually. For example, in choanoflagellates, Src and Csk are both active, but the negative regulatory mechanism is reportedly absent. In filastereans, a protist clade closely related to choanoflagellates, Src is active, but Csk is apparently inactive. In this study, we use a combination of bioinformatics, in vitro kinase assays, and yeast-based growth assays to characterize holozoan Src and Csk orthologs. We show that, despite appreciable differences in domain architecture, Csk from Corallochytrium limacisporum , a highly diverged holozoan marine protist, is active and can inhibit Src. However, in comparison with other Csk orthologs, Corallochytrium Csk displays broad substrate specificity and inhibits Src in an activity-independent manner. Furthermore, in contrast to previous studies, we show that Csk from the filasterean Capsaspora owczarzaki is active and that the Csk-Src negative regulatory mechanism is present in Csk and Src proteins from C. owczarzaki and the choanoflagellate Monosiga brevicollis Our results suggest that negative regulation of Src by Csk is more ancient than previously thought and that it might be conserved across all holozoan species. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Semiconductor technology in protein kinase research and drug discovery: sensing a revolution.

    Science.gov (United States)

    Bhalla, Nikhil; Di Lorenzo, Mirella; Estrela, Pedro; Pula, Giordano

    2017-02-01

    Since the discovery of protein kinase activity in 1954, close to 600 kinases have been discovered that have crucial roles in cell physiology. In several pathological conditions, aberrant protein kinase activity leads to abnormal cell and tissue physiology. Therefore, protein kinase inhibitors are investigated as potential treatments for several diseases, including dementia, diabetes, cancer and autoimmune and cardiovascular disease. Modern semiconductor technology has recently been applied to accelerate the discovery of novel protein kinase inhibitors that could become the standard-of-care drugs of tomorrow. Here, we describe current techniques and novel applications of semiconductor technologies in protein kinase inhibitor drug discovery. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Subcloning, expression, purification, and characterization of Haemophilus influenzae glycerol kinase.

    Science.gov (United States)

    Pawlyk, A C; Pettigrew, D W

    2001-06-01

    Glycerol kinase (EC 2.7.1.30) is a bacterial sugar kinase and a member of the sugar kinase/actin/hsc-70 superfamily of enzymes. The enzyme from Escherichia coli is an allosteric regulatory enzyme whose activity is inhibited by fructose 1,6-bisphosphate (FBP) and the glucose-specific phosphocarrier of the phosphoenolpyruvate:glycose phosphotransferase system, IIA(Glc) (previously termed III(Glc)). Comparison of its primary structure with that of the highly similar Haemophilus influenzae glycerol kinase reveals that the amino acid sequence for the binding site for FBP is conserved while the amino acid sequence for the binding site for IIA(Glc) contains differences that are predicted to prevent its inhibition. To test this hypothesis, the H. influenzae glpK gene was assembled from DNA library fragments and subcloned into pUC18. The enzyme is expressed at high levels in E. coli. It was purified to greater than 90% homogeneity by taking advantage of its solubility behavior in a procedure that requires no column chromatography. The initial-velocity kinetic parameters of the purified enzyme are similar to those of the E. coli glycerol kinase. The H. influenzae glycerol kinase is inhibited by FBP but not by IIA(Glc), in agreement with the prediction based on sequence comparison. Sedimentation velocity experiments reveal that inhibition of HiGK by FBP is associated with oligomerization, behavior which is similar to EcGK. The possibility of utilizing mutagenesis studies to exploit the high degree of similarity of these two enzymes to elucidate the mechanism of allosteric regulation by IIA(Glc) is discussed. Copyright 2001 Academic Press.

  8. Enzymatic assay for calmodulins based on plant NAD kinase activity

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, A.C.; Jarrett, H.W.; Cormier, M.J.

    1984-01-01

    NAD kinase with increased sensitivity to calmodulin was purified from pea seedlings (Pisum sativum L., Willet Wonder). Assays for calmodulin based on the activities of NAD kinase, bovine brain cyclic nucleotide phosphodiesterase, and human erythrocyte Ca/sup 2 -/-ATPase were compared for their sensitivities to calmodulin and for their abilities to discriminate between calmodulins from different sources. The activities of the three enzymes were determined in the presence of various concentrations of calmodulins from human erythrocyte, bovine brain, sea pansy (Renilla reniformis), mung bean seed (Vigna radiata L. Wilczek), mushroom (Agaricus bisporus), and Tetrahymena pyriformis. The concentrations of calmodulin required for 50% activation of the NAD kinase (K/sub 0.5/) ranged from 0.520 ng/ml for Tetrahymena to 2.20 ng/ml for bovine brain. The A/sub 0.5/ s ranged from 19.6 ng/ml for bovine brain calmodulin to 73.5 ng/ml for mushroom calmodulin for phosphodiesterase activation. The K/sub 0.5/'s for the activation of Ca/sup 2 +/-ATPase ranged from 36.3 ng/mol for erythrocyte calmodulin to 61.7 ng/ml for mushroom calmodulin. NAD kinase was not stimulated by phosphatidylcholine, phosphatidylserine, cardiolipin, or palmitoleic acid in the absence or presence of Ca/sup 2 +/. Palmitic acid had a slightly stimulatory effect in the presence of Ca/sup 2 +/ (10% of maximum), but no effect in the absence of Ca/sup 2 +/. Palmitoleic acid inhibited the calmodulin-stimulated activity by 50%. Both the NAD kinase assay and radioimmunoassay were able to detect calmodulin in extracts containing low concentrations of calmodulin. Estimates of calmodulin contents of crude homogenates determined by the NAD kinase assay were consistent with amounts obtained by various purification procedures. 30 references, 1 figure, 4 tables.

  9. Characterization of pathogenic germline mutations in human Protein Kinases

    Directory of Open Access Journals (Sweden)

    Orengo Christine A

    2011-07-01

    Full Text Available Abstract Background Protein Kinases are a superfamily of proteins involved in crucial cellular processes such as cell cycle regulation and signal transduction. Accordingly, they play an important role in cancer biology. To contribute to the study of the relation between kinases and disease we compared pathogenic mutations to neutral mutations as an extension to our previous analysis of cancer somatic mutations. First, we analyzed native and mutant proteins in terms of amino acid composition. Secondly, mutations were characterized according to their potential structural effects and finally, we assessed the location of the different classes of polymorphisms with respect to kinase-relevant positions in terms of subfamily specificity, conservation, accessibility and functional sites. Results Pathogenic Protein Kinase mutations perturb essential aspects of protein function, including disruption of substrate binding and/or effector recognition at family-specific positions. Interestingly these mutations in Protein Kinases display a tendency to avoid structurally relevant positions, what represents a significant difference with respect to the average distribution of pathogenic mutations in other protein families. Conclusions Disease-associated mutations display sound differences with respect to neutral mutations: several amino acids are specific of each mutation type, different structural properties characterize each class and the distribution of pathogenic mutations within the consensus structure of the Protein Kinase domain is substantially different to that for non-pathogenic mutations. This preferential distribution confirms previous observations about the functional and structural distribution of the controversial cancer driver and passenger somatic mutations and their use as a proxy for the study of the involvement of somatic mutations in cancer development.

  10. Phosphorylation sites of Arabidopsis MAP Kinase Substrate 1 (MKS1)

    DEFF Research Database (Denmark)

    Caspersen, M.B.; Qiu, J.-L.; Zhang, X.

    2007-01-01

    The Arabidopsis MAP kinase 4 (MPK4) substrate MKS1 was expressed in Escherichia coli and purified, full-length, 6x histidine (His)-tagged MKS1 was phosphorylated in vitro by hemagglutinin (HA)-tagged MPK4 immuno-precipitated from plants. MKS1 phosphorylation was initially verified by electrophore......The Arabidopsis MAP kinase 4 (MPK4) substrate MKS1 was expressed in Escherichia coli and purified, full-length, 6x histidine (His)-tagged MKS1 was phosphorylated in vitro by hemagglutinin (HA)-tagged MPK4 immuno-precipitated from plants. MKS1 phosphorylation was initially verified...

  11. Proteinase K processing of rabbit muscle creatine kinase

    DEFF Research Database (Denmark)

    Leydier, C; Andersen, Jens S.; Couthon, F

    1997-01-01

    Proteinase K cleaves selectively both cytosolic and mitochondrial isoforms of creatine kinase leading to the appearance of two fragments, a large N-terminal one (K1) and a small C-terminal peptide (K2) which remain associated together. The loss of enzymatic activity correlates with the extent...... of monomer cleavage. N-terminal sequencing of the K2 fragments from rabbit cytosolic and pig mitochondrial creatine kinase shows that these peptides begin with A328 and A324, respectively. Electrospray ionization mass spectrometry demonstrates that K2 peptide is composed of 53 residues (A328-K380). However...

  12. Structural Changes of Creatine Kinase upon Substrate Binding

    OpenAIRE

    Forstner, Michael; Kriechbaum, Manfred; Laggner, Peter; Wallimann, Theo

    1998-01-01

    Small-angle x-ray scattering was used to investigate structural changes upon binding of individual substrates or a transition state analog complex (TSAC; Mg-ADP, creatine, and KNO3) to creatine kinase (CK) isoenzymes (dimeric muscle-type (M)-CK and octameric mitochondrial (Mi)-CK) and monomeric arginine kinase (AK). Considerable changes in the shape and the size of the molecules occurred upon binding of Mg-nucleotide or TSAC. The radius of gyration of Mi-CK was reduced from 55.6 A (free enzym...

  13. Creatine kinase MB isoenzyme in dermatomyositis: a noncardiac source

    Energy Technology Data Exchange (ETDEWEB)

    Larca, L.J.; Coppola, J.T.; Honig, S.

    1981-03-01

    Three patients with polymyositis had elevated serum levels of creatine kinase MB isoenzyme. The presence of this isoenzyme is used extensively to diagnose myocardial infarction, but the isoenzyme is also found in sera of patients with primary muscular and neuromuscular disorders. Researchers studied cardiac function in two of our patients with electrocardiograms, technetium stannous pyrophosphate scanning, and technetium 99m-labeled erythrocyte gated blood pool imaging and in the third patient by postmortem examination. There was no evidence of myocardial involvement to account for the high serum levels of isoenzyme. Creatine kinase MB in the sera of patients with polymyositis does not necessarily indicate myocardial necrosis.

  14. Cyclin dependent kinase (CDK) inhibitors as anticancer drugs.

    Science.gov (United States)

    Sánchez-Martínez, Concepción; Gelbert, Lawrence M; Lallena, María José; de Dios, Alfonso

    2015-09-01

    Sustained proliferative capacity is a hallmark of cancer. In mammalian cells proliferation is controlled by the cell cycle, where cyclin-dependent kinases (CDKs) regulate critical checkpoints. CDK4 and CDK6 are considered highly validated anticancer drug targets due to their essential role regulating cell cycle progression at the G1 restriction point. This review provides an overview of recent advances on cyclin dependent kinase inhibitors in general with special emphasis on CDK4 and CDK6 inhibitors and compounds under clinical evaluation. Chemical structures, structure activity relationships, and relevant preclinical properties will be described. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. A structural informatics approach to mine kinase knowledge bases.

    Science.gov (United States)

    Brooijmans, Natasja; Mobilio, Dominick; Walker, Gary; Nilakantan, Ramaswamy; Denny, Rajiah A; Feyfant, Eric; Diller, David; Bikker, Jack; Humblet, Christine

    2010-03-01

    In this paper, we describe a combination of structural informatics approaches developed to mine data extracted from existing structure knowledge bases (Protein Data Bank and the GVK database) with a focus on kinase ATP-binding site data. In contrast to existing systems that retrieve and analyze protein structures, our techniques are centered on a database of ligand-bound geometries in relation to residues lining the binding site and transparent access to ligand-based SAR data. We illustrate the systems in the context of the Abelson kinase and related inhibitor structures. 2009 Elsevier Ltd. All rights reserved.

  16. Crystal structure of human protein kinase CK2

    DEFF Research Database (Denmark)

    Niefind, K; Guerra, B; Ermakowa, I

    2001-01-01

    The crystal structure of a fully active form of human protein kinase CK2 (casein kinase 2) consisting of two C-terminally truncated catalytic and two regulatory subunits has been determined at 3.1 A resolution. In the CK2 complex the regulatory subunits form a stable dimer linking the two catalytic...... subunits, which make no direct contact with one another. Each catalytic subunit interacts with both regulatory chains, predominantly via an extended C-terminal tail of the regulatory subunit. The CK2 structure is consistent with its constitutive activity and with a flexible role of the regulatory subunit...

  17. Dominant negative selection of vaccinia virus using a thymidine kinase/thymidylate kinase fusion gene and the prodrug azidothymidine

    International Nuclear Information System (INIS)

    Holzer, Georg W.; Mayrhofer, Josef; Gritschenberger, Werner; Falkner, Falko G.

    2005-01-01

    The Escherichia coli thymidine kinase/thymidylate kinase (tk/tmk) fusion gene encodes an enzyme that efficiently converts the prodrug 3'-azido-2',3'-dideoxythymidine (AZT) into its toxic triphosphate derivative, a substance which stops DNA chain elongation. Integration of this marker gene into vaccinia virus that normally is not inhibited by AZT allowed the establishment of a powerful selection procedure for recombinant viruses. In contrast to the conventional vaccinia thymidine kinase (tk) selection that is performed in tk-negative cell lines, AZT selection can be performed in normal (tk-positive) cell lines. The technique is especially useful for the generation of replication-deficient vaccinia viruses and may also be used for gene knock-out studies of essential vaccinia genes

  18. Modulation of mitogen-activated protein kinase-activated protein kinase 3 by hepatitis C virus core protein

    DEFF Research Database (Denmark)

    Ngo, HT; Pham, Long; Kim, JW

    2013-01-01

    and protein levels of MAPKAPK3 were elevated in both HCV subgenomic replicon cells and cell culture-derived HCV (HCVcc)-infected cells. Silencing of MAPKAPK3 expression resulted in decreases in both protein and HCV infectivity levels but not in the intracellular HCV RNA level. We showed that MAPKAPK3......Hepatitis C virus (HCV) is highly dependent on cellular proteins for its own propagation. In order to identify the cellular factors involved in HCV propagation, we performed protein microarray assays using the HCV core protein as a probe. Of ~9,000 host proteins immobilized in a microarray......, approximately 100 cellular proteins were identified as HCV core-interacting partners. Of these candidates, mitogen-activated protein kinase-activated protein kinase 3 (MAPKAPK3) was selected for further characterization. MAPKAPK3 is a serine/threonine protein kinase that is activated by stress and growth...

  19. Functional diversity of human protein kinase splice variants marks significant expansion of human kinome

    Directory of Open Access Journals (Sweden)

    Anamika Krishanpal

    2009-12-01

    Full Text Available Abstract Background Protein kinases are involved in diverse spectrum of cellular processes. Availability of draft version of the human genomic data in the year 2001 enabled recognition of repertoire of protein kinases. However, over the years the human genomic data is being refined and the current release of human genomic data has helped us to recognize a larger repertoire of over 900 human protein kinases represented mainly by splice variants. Results Many of these identified protein kinases are alternatively spliced products. Interestingly, some of the human kinase splice variants appear to be significantly diverged in terms of their functional properties as represented by incorporation or absence of one or more domains. Many sets of protein kinase splice variants have substantially different domain organization and in a few sets of splice variants kinase domains belong to different subfamilies of kinases suggesting potential participation in different signal transduction pathways. Conclusions Addition or deletion of a domain between splice variants of multi-domain kinases appears to be a means of generating differences in the functional features of otherwise similar kinases. It is intriguing that marked sequence diversity within the catalytic regions of some of the splice variant kinases result in kinases belonging to different subfamilies. These human kinase splice variants with different functions might contribute to diversity of eukaryotic cellular signaling.

  20. Tyrosine kinase, aurora kinase and leucine aminopeptidase as attractive drug targets in anticancer therapy - characterisation of their inhibitors.

    Science.gov (United States)

    Ziemska, Joanna; Solecka, Jolanta

    Cancers are the leading cause of deaths all over the world. Available anticancer agents used in clinics exhibit low therapeutic index and usually high toxicity. Wide spreading drug resistance of cancer cells induce a demanding need to search for new drug targets. Currently, many on-going studies on novel compounds with potent anticancer activity, high selectivity as well as new modes of action are conducted. In this work, we describe in details three enzyme groups, which are at present of extensive interest to medical researchers and pharmaceutical companies. These include receptor tyrosine kinases (e.g. EGFR enzymes) and non-receptor tyrosine kinases (Src enzymes), type A, B and C Aurora kinases and aminopeptidases, especially leucine aminopeptidase. We discuss classification of these enzymes, biochemistry as well as their role in the cell cycle under normal conditions and during cancerogenesis. Further on, the work describes enzyme inhibitors that are under in vitro, preclinical, clinical studies as well as drugs available on the market. Both, chemical structures of discovered inhibitors and the role of chemical moieties in novel drug design are discussed. Described enzymes play essential role in cell cycle, especially in mitosis (Aurora kinases), cell differentiation, growth and apoptosis (tyrosine kinases) as well as G1/S transition (leucine aminopeptidase). In cancer cells, they are overexpressed and only their inhibition may stop tumor progression. This review presents the clinical outcomes of selected inhibitors and argues the safety of drug usage in human volunteers. Clinical studies of EGFR and Src kinase inhibitors in different tumors clearly show the need for molecular selection of patients (to those with mutations in genes coding EGFR and Src) to achieve positive clinical response. Current data indicates the great necessity for new anticancer treatment and actions to limit off-target activity.

  1. Phosphorylation of Dgk1 Diacylglycerol Kinase by Casein Kinase II Regulates Phosphatidic Acid Production in Saccharomyces cerevisiae.

    Science.gov (United States)

    Qiu, Yixuan; Hassaninasab, Azam; Han, Gil-Soo; Carman, George M

    2016-12-16

    In the yeast Saccharomyces cerevisiae, Dgk1 diacylglycerol (DAG) kinase catalyzes the CTP-dependent phosphorylation of DAG to form phosphatidic acid (PA). The enzyme in conjunction with Pah1 PA phosphatase controls the levels of PA and DAG for the synthesis of triacylglycerol and membrane phospholipids, the growth of the nuclear/endoplasmic reticulum membrane, and the formation of lipid droplets. Little is known about how DAG kinase activity is regulated by posttranslational modification. In this work, we examined the phosphorylation of Dgk1 DAG kinase by casein kinase II (CKII). When phosphate groups were globally reduced using nonspecific alkaline phosphatase, Triton X-100-solubilized membranes from DGK1-overexpressing cells showed a 7.7-fold reduction in DAG kinase activity; the reduced enzyme activity could be increased 5.5-fold by treatment with CKII. Dgk1(1-77) expressed heterologously in Escherichia coli was phosphorylated by CKII on a serine residue, and its phosphorylation was dependent on time as well as on the concentrations of CKII, ATP, and Dgk1(1-77). We used site-specific mutagenesis, coupled with phosphorylation analysis and phosphopeptide mapping, to identify Ser-45 and Ser-46 of Dgk1 as the CKII target sites, with Ser-46 being the major phosphorylation site. In vivo, the S46A and S45A/S46A mutations of Dgk1 abolished the stationary phase-dependent stimulation of DAG kinase activity. In addition, the phosphorylation-deficient mutations decreased Dgk1 function in PA production and in eliciting pah1Δ phenotypes, such as the expansion of the nuclear/endoplasmic reticulum membrane, reduced lipid droplet formation, and temperature sensitivity. This work demonstrates that the CKII-mediated phosphorylation of Dgk1 regulates its function in the production of PA. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Phosphorylation of Dgk1 Diacylglycerol Kinase by Casein Kinase II Regulates Phosphatidic Acid Production in Saccharomyces cerevisiae*

    Science.gov (United States)

    Qiu, Yixuan; Hassaninasab, Azam; Han, Gil-Soo; Carman, George M.

    2016-01-01

    In the yeast Saccharomyces cerevisiae, Dgk1 diacylglycerol (DAG) kinase catalyzes the CTP-dependent phosphorylation of DAG to form phosphatidic acid (PA). The enzyme in conjunction with Pah1 PA phosphatase controls the levels of PA and DAG for the synthesis of triacylglycerol and membrane phospholipids, the growth of the nuclear/endoplasmic reticulum membrane, and the formation of lipid droplets. Little is known about how DAG kinase activity is regulated by posttranslational modification. In this work, we examined the phosphorylation of Dgk1 DAG kinase by casein kinase II (CKII). When phosphate groups were globally reduced using nonspecific alkaline phosphatase, Triton X-100-solubilized membranes from DGK1-overexpressing cells showed a 7.7-fold reduction in DAG kinase activity; the reduced enzyme activity could be increased 5.5-fold by treatment with CKII. Dgk1(1–77) expressed heterologously in Escherichia coli was phosphorylated by CKII on a serine residue, and its phosphorylation was dependent on time as well as on the concentrations of CKII, ATP, and Dgk1(1–77). We used site-specific mutagenesis, coupled with phosphorylation analysis and phosphopeptide mapping, to identify Ser-45 and Ser-46 of Dgk1 as the CKII target sites, with Ser-46 being the major phosphorylation site. In vivo, the S46A and S45A/S46A mutations of Dgk1 abolished the stationary phase-dependent stimulation of DAG kinase activity. In addition, the phosphorylation-deficient mutations decreased Dgk1 function in PA production and in eliciting pah1Δ phenotypes, such as the expansion of the nuclear/endoplasmic reticulum membrane, reduced lipid droplet formation, and temperature sensitivity. This work demonstrates that the CKII-mediated phosphorylation of Dgk1 regulates its function in the production of PA. PMID:27834677

  3. Stress-induced activation of protein kinase CK2 by direct interaction with p38 mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Sayed, M; Kim, S O; Salh, B S

    2000-01-01

    Protein kinase CK2 has been implicated in the regulation of a wide range of proteins that are important in cell proliferation and differentiation. Here we demonstrate that the stress signaling agents anisomycin, arsenite, and tumor necrosis factor-alpha stimulate the specific enzyme activity of CK2...... to be an allosteric mechanism. Furthermore, we demonstrate that anisomycin- and tumor necrosis factor-alpha-induced phosphorylation of p53 at Ser-392, which is important for the transcriptional activity of this growth suppressor protein, requires p38 MAP kinase and CK2 activities....

  4. Extracellular signal-regulated kinases control expression of G protein-coupled receptor kinase 2 (GRK2)

    DEFF Research Database (Denmark)

    Theilade, Juliane; Lerche Hansen, Jakob; Haunsø, Stig

    2002-01-01

    G protein-coupled receptor kinase 2 (GRK2) phosphorylates G protein-coupled receptors resulting in uncoupling from G proteins. Receptors modulate GRK2 expression, however the mechanistic basis for this effect is largely unknown. Here we report a novel mechanism by which receptors use...... the extracellular signal-regulated kinase (ERK) cascade to regulate GRK2 cellular levels. ERK activation by receptor stimulation elevated endogenous GRK2 while antagonist treatment decreased cellular GRK2. Activating ERK by overexpressing constitutive active MEK-1 or Ras elevated GRK2 protein levels while blocking...

  5. The DNA-dependent protein kinase: a multifunctional protein kinase with roles in DNA double strand break repair and mitosis

    OpenAIRE

    Jette, Nicholas; Lees-Miller, Susan P.

    2014-01-01

    The DNA-dependent protein kinase (DNA-PK) is a serine/threonine protein kinase composed of a large catalytic subunit (DNA-PKcs) and the Ku70/80 heterodimer. Over the past two decades, significant progress has been made in elucidating the role of DNA-PK in non-homologous end joining (NHEJ), the major pathway for repair of ionizing radiation-induced DNA double strand breaks in human cells and recently, additional roles for DNA-PK have been reported. In this review, we will describe the biochemi...

  6. Mycosporine-Like Amino Acids Promote Wound Healing through Focal Adhesion Kinase (FAK) and Mitogen-Activated Protein Kinases (MAP Kinases) Signaling Pathway in Keratinocytes

    Science.gov (United States)

    Choi, Yun-Hee; Yang, Dong Joo; Kulkarni, Atul; Moh, Sang Hyun; Kim, Ki Woo

    2015-01-01

    Mycosporine-like amino acids (MAAs) are secondary metabolites found in diverse marine, freshwater, and terrestrial organisms. Evidence suggests that MAAs have several beneficial effects on skin homeostasis such as protection against UV radiation and reactive oxygen species (ROS). In addition, MAAs are also involved in the modulation of skin fibroblasts proliferation. However, the regulatory function of MAAs on wound repair in human skin is not yet clearly elucidated. To investigate the roles of MAAs on the wound healing process in human keratinocytes, three MAAs, Shinorine (SH), Mycosporine-glycine (M-Gly), and Porphyra (P334) were purified from Chlamydomonas hedlyei and Porphyra yezoensis. We found that SH, M-Gly, and P334 have significant effects on the wound healing process in human keratinocytes and these effects were mediated by activation of focal adhesion kinases (FAK), extracellular signal-regulated kinases (ERK), and c-Jun N-terminal kinases (JNK). These results suggest that MAAs accelerate wound repair by activating the FAK-MAPK signaling pathways. This study also indicates that MAAs can act as a new wound healing agent and further suggests that MAAs might be a novel biomaterial for wound healing therapies. PMID:26703626

  7. Mycosporine-Like Amino Acids Promote Wound Healing through Focal Adhesion Kinase (FAK and Mitogen-Activated Protein Kinases (MAP Kinases Signaling Pathway in Keratinocytes

    Directory of Open Access Journals (Sweden)

    Yun-Hee Choi

    2015-11-01

    Full Text Available Mycosporine-like amino acids (MAAs are secondary metabolites found in diverse marine, freshwater, and terrestrial organisms. Evidence suggests that MAAs have several beneficial effects on skin homeostasis such as protection against UV radiation and reactive oxygen species (ROS. In addition, MAAs are also involved in the modulation of skin fibroblasts proliferation. However, the regulatory function of MAAs on wound repair in human skin is not yet clearly elucidated. To investigate the roles of MAAs on the wound healing process in human keratinocytes, three MAAs, Shinorine (SH, Mycosporine-glycine (M-Gly, and Porphyra (P334 were purified from Chlamydomonas hedlyei and Porphyra yezoensis. We found that SH, M-Gly, and P334 have significant effects on the wound healing process in human keratinocytes and these effects were mediated by activation of focal adhesion kinases (FAK, extracellular signal-regulated kinases (ERK, and c-Jun N-terminal kinases (JNK. These results suggest that MAAs accelerate wound repair by activating the FAK-MAPK signaling pathways. This study also indicates that MAAs can act as a new wound healing agent and further suggests that MAAs might be a novel biomaterial for wound healing therapies.

  8. Effect of cyclic hydrodynamic pressure-induced proliferation of human bladder smooth muscle through Ras-related C3 botulinum toxin substrate 1, mitogen-activated protein kinase kinase 1/2 and extracellular regulated protein kinases 1/2.

    Science.gov (United States)

    Wu, Tao; Chen, Lin; Wei, Tangqiang; Wang, Yan; Xu, Feng; Wang, Kunjie

    2012-09-01

    To examine the role of Ras-related C3 botulinum toxin substrate 1, mitogen-activated protein kinase kinase 1/2 and extracellular regulated protein kinases 1/2 in the cyclic hydrodynamic pressure-induced proliferation of human bladder smooth muscle cells. Human bladder smooth muscle cells were exposed to cyclic hydrodynamic pressures in vitro with defined parameters (static, 100 cmH(2) O, 200 cmH(2) O and 300 cmH(2) O pressure) for 24 h. The proliferation of cells was assessed by flow cytometry. Ras-related C3 botulinum toxin substrate 1, mitogen-activated protein kinase kinase 1/2 and extracellular regulated protein kinases 1/2 messenger ribonucleic acid, and protein expression was analyzed by real-time polymerase chain reaction and Western blot. Specificity of the Rac1 was determined with real-time polymerase chain reaction and Western blot technique with small interfering ribonucleic acid transfection and Rac1 inhibitor (NSC23766). The proliferation of human bladder smooth muscle cells was increased. Ras-related C3 botulinum toxin substrate 1, mitogen-activated protein kinase kinase 1/2 and extracellular regulated protein kinases 1/2 were activated by 200 and 300 cmH(2) O cyclic hydrodynamic pressure compared with static and 100 cmH(2) O pressure. The "knockdown" of activation of Rac1 using target small interfering ribonucleic acid transfection and Rac1 inhibitor (NSC23766) decreased proliferation of human bladder smooth muscle cells, and downregulated mitogen-activated protein kinase kinase 1/2, extracellular regulated protein kinases 1/2. The Rac1 pathway is activated in mechanotransduction and regulation of human bladder smooth muscle cell proliferation in response to cyclic hydrodynamic pressure. © 2012 The Japanese Urological Association.

  9. Interleukin-1 activates a novel protein kinase cascade that results in the phosphorylation of Hsp27.

    Science.gov (United States)

    Freshney, N W; Rawlinson, L; Guesdon, F; Jones, E; Cowley, S; Hsuan, J; Saklatvala, J

    1994-09-23

    An IL-1-stimulated protein kinase cascade resulting in phosphorylation of the small heat shock protein hsp27 has been identified in KB cells. It is distinct from the p42 MAP kinase cascade. An upstream activator kinase phosphorylated a 40 kDa kinase (p40) upon threonine and tyrosine residues, which in turn phosphorylated a 50 kDa kinase (p50) upon threonine (and some serine) residues. p50 phosphorylated hsp27 upon serine. p40 and p50 were purified to near homogeneity. All three components were inactivated by protein phosphatase 2A, and p40 was inactivated by protein tyrosine phosphatase 1B. The substrate specificity of p40 differed from that of p42 and p54 MAP kinases. The upstream activator was not a MAP kinase kinase. p50 resembled MAPKAPK-2 and may be identical.

  10. Clinical Pharmacology of Kinase Inhibitors in Oncology : Personalized and Optimzed Dosing

    NARCIS (Netherlands)

    Verheijen, Remy B.

    2017-01-01

    Kinase inhibitors are an important category of molecularly targeted therapies used for cancer. Verheijen’s doctoral thesis describes several clinical pharmacological studies to optimize and personalize the treatment of cancer with kinase inhibitors, using pharmacokinetics, molecular imaging and

  11. A BCR-ABL Kinase Activity-Independent Signaling Pathway in Chronic Myelogenous Leukemia

    National Research Council Canada - National Science Library

    Li, Shaoguang

    2008-01-01

    .... We identified Src kinases as key molecules in this BCR- ABL kinase activity-independent pathway and they are essential for leukemic cells to survive imatinib treatment and for CML transition to lymphoid blast crisis...

  12. A dynamically coupled allosteric network underlies binding cooperativity in Src kinase

    Science.gov (United States)

    Foda, Zachariah H.; Shan, Yibing; Kim, Eric T.; Shaw, David E.; Seeliger, Markus A.

    2015-01-01

    Protein tyrosine kinases are attractive drug targets because many human diseases are associated with the deregulation of kinase activity. However, how the catalytic kinase domain integrates different signals and switches from an active to an inactive conformation remains incompletely understood. Here we identify an allosteric network of dynamically coupled amino acids in Src kinase that connects regulatory sites to the ATP- and substrate-binding sites. Surprisingly, reactants (ATP and peptide substrates) bind with negative cooperativity to Src kinase while products (ADP and phosphopeptide) bind with positive cooperativity. We confirm the molecular details of the signal relay through the allosteric network by biochemical studies. Experiments on two additional protein tyrosine kinases indicate that the allosteric network may be largely conserved among these enzymes. Our work provides new insights into the regulation of protein tyrosine kinases and establishes a potential conduit by which resistance mutations to ATP-competitive kinase inhibitors can affect their activity.

  13. Creatine kinase response to high-intensity aerobic exercise in adult-onset muscular dystrophy

    DEFF Research Database (Denmark)

    Andersen, Søren P; Sveen, Marie-Louise; Hansen, Regitze S

    2013-01-01

    We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies.......We investigated the effect of high-intensity exercise on plasma creatine kinase (CK) in patients with muscular dystrophies....

  14. A dynamically coupled allosteric network underlies binding cooperativity in Src kinase.

    Science.gov (United States)

    Foda, Zachariah H; Shan, Yibing; Kim, Eric T; Shaw, David E; Seeliger, Markus A

    2015-01-20

    Protein tyrosine kinases are attractive drug targets because many human diseases are associated with the deregulation of kinase activity. However, how the catalytic kinase domain integrates different signals and switches from an active to an inactive conformation remains incompletely understood. Here we identify an allosteric network of dynamically coupled amino acids in Src kinase that connects regulatory sites to the ATP- and substrate-binding sites. Surprisingly, reactants (ATP and peptide substrates) bind with negative cooperativity to Src kinase while products (ADP and phosphopeptide) bind with positive cooperativity. We confirm the molecular details of the signal relay through the allosteric network by biochemical studies. Experiments on two additional protein tyrosine kinases indicate that the allosteric network may be largely conserved among these enzymes. Our work provides new insights into the regulation of protein tyrosine kinases and establishes a potential conduit by which resistance mutations to ATP-competitive kinase inhibitors can affect their activity.

  15. Casein kinase 2 dependent phosphorylation of neprilysin regulates receptor tyrosine kinase signaling to Akt.

    Directory of Open Access Journals (Sweden)

    Martin Siepmann

    2010-10-01

    Full Text Available Neprilysin (NEP is a type II membrane metalloproteinase that cleaves physiologically active peptides at the cell surface thus regulating the local concentration of these peptides available for receptor binding and signal transduction. In addition, the cytoplasmic N-terminal domain of NEP interacts with the phosphatase and tensin homologue deleted on chromosome 10 (PTEN thereby regulating intracellular signaling via Akt. Thus, NEP serves dual functions in extracellular and intracellular signal transduction. Here, we show that NEP undergoes phosphorylation at serine residue 6 within the N-terminal cytoplasmic domain. In vitro and cell culture experiments demonstrate that Ser 6 is efficiently phosphorylated by protein kinase CK2. The phosphorylation of the cytoplasmic domain of NEP inhibits its interaction with PTEN. Interestingly, expression of a pseudophosphorylated NEP variant (Ser6Asp abrogates the inhibitory effect of NEP on insulin/insulin-like growth factor-1 (IGF-1 stimulated activation of Akt. Thus, our data demonstrate a regulatory role of CK2 in the interaction of NEP with PTEN and insulin/IGF-1 signaling.

  16. Thymidine plaque autoradiography of thymidine kinase-positive and thymidine kinase-negative herpesviruses

    International Nuclear Information System (INIS)

    Tenser, R.B.; Jones, J.C.; Ressel, S.J.; Fralish, F.A.

    1983-01-01

    Plaques formed by herpes simplex virus (HSV), pseudorabies virus, and varicella-zoster virus were studied by plaque autoradiography after [ 14 C]thymidine labeling. Standard thymidine kinase-positive (TK+) viruses and TK- mutants of HSV types 1 and 2 and pseudorabies virus were studied, including cell cultured viruses and viruses isolated from animals. Autoradiography was performed with X-ray film with an exposure time of 5 days. After development of films, TK+ plaques showed dark rims due to isotope incorporation, whereas TK- plaques were minimally labeled. Plaque autoradiography of stock TK- viruses showed reversion frequencies to the TK+ phenotype of less than 10(-3). Autoradiography indicated that TK- virus retained the TK- phenotype after replication in vivo. In addition, it was shown that TK- HSV could be isolated from mouse trigeminal ganglion tissue after corneal inoculation of TK- HSV together with TK+ HSV. The plaque autoradiographic procedure was very useful to evaluate proportions of TK+ and TK- virus present in TK+-TK- virus mixtures

  17. Mammalian STE20-like kinase 2, not kinase 1, mediates photoreceptor cell death during retinal detachment

    Science.gov (United States)

    Matsumoto, H; Murakami, Y; Kataoka, K; Lin, H; Connor, K M; Miller, J W; Zhou, D; Avruch, J; Vavvas, D G

    2014-01-01

    Photoreceptor cell death is the definitive cause of vision loss in retinal detachment (RD). Mammalian STE20-like kinase (MST) is a master regulator of both cell death and proliferation and a critical factor in development and tumorigenesis. However, to date the role of MST in neurodegeneration has not been fully explored. Utilizing MST1−/− and MST2−/− mice we identified MST2, but not MST1, as a regulator of photoreceptor cell death in a mouse model of RD. MST2−/− mice demonstrated significantly decreased photoreceptor cell death and outer nuclear layer (ONL) thinning after RD. Additionally, caspase-3 activation was attenuated in MST2−/− mice compared to control mice after RD. The transcription of p53 upregulated modulator of apoptosis (PUMA) and Fas was also reduced in MST2−/− mice post-RD. Retinas of MST2−/− mice displayed suppressed nuclear relocalization of phosphorylated YAP after RD. Consistent with the reduction of photoreceptor cell death, MST2−/− mice showed decreased levels of proinflammatory cytokines such as monocyte chemoattractant protein 1 and interleukin 6 as well as attenuated inflammatory CD11b cell infiltration during the early phase of RD. These results identify MST2, not MST1, as a critical regulator of caspase-mediated photoreceptor cell death in the detached retina and indicate its potential as a future neuroprotection target. PMID:24874741

  18. Understanding doublecortin-like kinase gene function through transgenesis

    NARCIS (Netherlands)

    Schenk, Geert J.

    2010-01-01

    Doublecortin (DCX) and DCX-domain containing Doublecortin-Like Kinase (DCLK) gene splice variants function during embryonic development, where they play a role in microtubule binding. Although a role for the DCLK gene during embryogenesis is clearly established, it encodes multiple, different

  19. FDA-approved small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Nielsen, Thomas E.; Clausen, Mads Hartvig

    2015-01-01

    Kinases have emerged as one of the most intensivelypursued targets in current pharmacological research,especially for cancer, due to their critical roles in cellularsignaling. To date, the US FDA has approved 28 smallmoleculekinase inhibitors, half of which were approvedin the past 3 years. While...

  20. Evaluation of Creatine Kinase Activity and Inorganic Phosphate ...

    African Journals Online (AJOL)

    subjects presenting with major VOC. Keywords: Serum creatine kinase activity, Serum inorganic phosphate concentration, Sickle cell disease,. Steady state, Vaso‑occlusive crisis. Original Article. Address for correspondence: Dr. John C Aneke,. Department of Hematology,. Nnamdi Azikiwe University Teaching. Hospital ...

  1. Expression of tyrosine kinase gene in mouse thymic stromal cells

    NARCIS (Netherlands)

    Rinke de Wit, T. F.; Izon, D. J.; Revilla, C.; Oosterwegel, M.; Bakker, A. Q.; van Ewijk, W.; Kruisbeek, A. M.

    1996-01-01

    Amongst the most important signal transduction molecules involved in regulating growth and differentiation are the protein tyrosine kinases (PTK). Since T cell development is a consequence of interactions between thymic stromal cells (TSC) and thymocytes, identification of the PTK in both

  2. Mathematical modelling of the MAP kinase pathway using proteomic datasets.

    Science.gov (United States)

    Tian, Tianhai; Song, Jiangning

    2012-01-01

    The advances in proteomics technologies offer an unprecedented opportunity and valuable resources to understand how living organisms execute necessary functions at systems levels. However, little work has been done up to date to utilize the highly accurate spatio-temporal dynamic proteome data generated by phosphoprotemics for mathematical modeling of complex cell signaling pathways. This work proposed a novel computational framework to develop mathematical models based on proteomic datasets. Using the MAP kinase pathway as the test system, we developed a mathematical model including the cytosolic and nuclear subsystems; and applied the genetic algorithm to infer unknown model parameters. Robustness property of the mathematical model was used as a criterion to select the appropriate rate constants from the estimated candidates. Quantitative information regarding the absolute protein concentrations was used to refine the mathematical model. We have demonstrated that the incorporation of more experimental data could significantly enhance both the simulation accuracy and robustness property of the proposed model. In addition, we used the MAP kinase pathway inhibited by phosphatases with different concentrations to predict the signal output influenced by different cellular conditions. Our predictions are in good agreement with the experimental observations when the MAP kinase pathway was inhibited by phosphatase PP2A and MKP3. The successful application of the proposed modeling framework to the MAP kinase pathway suggests that our method is very promising for developing accurate mathematical models and yielding insights into the regulatory mechanisms of complex cell signaling pathways.

  3. Tomato thymidine kinase is subject to inefficient TTP feedback regulation

    DEFF Research Database (Denmark)

    Larsen, Nicolai Balle; Munch-Petersen, Birgitte; Piskur, Jure

    2014-01-01

    A promising suicide gene therapy system to treat gliomas has been reported: the thymidine kinase 1 from tomato (toTK1) combined with the nucleoside analog pro-drug zidovudine (azidothymidine, AZT), which is known to penetrate the blood–brain barrier. Transduction with toTK1 has been found...

  4. ATR kinase regulates its attenuation via PPM1D phosphatase ...

    Indian Academy of Sciences (India)

    Debadrita Bhattacharya

    2018-02-07

    Feb 7, 2018 ... (Cdk2) (Hughes et al. 2013) leading to slowing down of cell cycle progression and prevention of pre-mature mitotic entry. Independent of Chk1, studies ... cancer cells and its function is thought to be regulated by DDR evoked by DNA Damage kinases (Lu et al. 2005a, b; Nan- nenga et al. 2006; Castellino et ...

  5. Regulation of Src Family Kinases in Human Cancers

    Science.gov (United States)

    Sen, Banibrata; Johnson, Faye M.

    2011-01-01

    The nonreceptor protein tyrosine kinase Src plays a crucial role in the signal transduction pathways involved in cell division, motility, adhesion, and survival in both normal and cancer cells. Although the Src family kinases (SFKs) are activated in various types of cancers, the exact mechanisms through which they contribute to the progression of individual tumors remain to be defined. The activation of Src in human cancers may occur through a variety of mechanisms that include domain interaction and structural remodeling in response to various activators or upstream kinases and phosphatastes. Because of Src's prominent roles in invasion and tumor progression, epithelial-to-mesenchymal transition, angiogenesis, and the development of metastasis, Src is a promising target for cancer therapy. Several small molecule inhibitors of Src are currently being investigated in clinical trials. In this article, we will summarize the mechanisms regulating Src kinase activity in normal and cancer cells and discuss the status of Src inhibitor development against various types of cancers. PMID:21776389

  6. G protein-coupled receptor kinase 2 promotes cardiac hypertrophy

    Science.gov (United States)

    Tscheschner, Henrike; Gao, Erhe; Schumacher, Sarah M.; Yuan, Ancai; Backs, Johannes; Most, Patrick; Wieland, Thomas; Koch, Walter J.; Katus, Hugo A.; Raake, Philip W.

    2017-01-01

    The increase in protein activity and upregulation of G-protein coupled receptor kinase 2 (GRK2) is a hallmark of cardiac stress and heart failure. Inhibition of GRK2 improved cardiac function and survival and diminished cardiac remodeling in various animal heart failure models. The aim of the present study was to investigate the effects of GRK2 on cardiac hypertrophy and dissect potential molecular mechanisms. In mice we observed increased GRK2 mRNA and protein levels following transverse aortic constriction (TAC). Conditional GRK2 knockout mice showed attenuated hypertrophic response with preserved ventricular geometry 6 weeks after TAC operation compared to wild-type animals. In isolated neonatal rat ventricular cardiac myocytes stimulation with angiotensin II and phenylephrine enhanced GRK2 expression leading to enhanced signaling via protein kinase B (PKB or Akt), consecutively inhibiting glycogen synthase kinase 3 beta (GSK3β), such promoting nuclear accumulation and activation of nuclear factor of activated T-cells (NFAT). Cardiac myocyte hypertrophy induced by in vitro GRK2 overexpression increased the cytosolic interaction of GRK2 and phosphoinositide 3-kinase γ (PI3Kγ). Moreover, inhibition of PI3Kγ as well as GRK2 knock down prevented Akt activation resulting in halted NFAT activity and reduced cardiac myocyte hypertrophy. Our data show that enhanced GRK2 expression triggers cardiac hypertrophy by GRK2-PI3Kγ mediated Akt phosphorylation and subsequent inactivation of GSK3β, resulting in enhanced NFAT activity. PMID:28759639

  7. Timeless links replication termination to mitotic kinase activation.

    Directory of Open Access Journals (Sweden)

    Jayaraju Dheekollu

    2011-05-01

    Full Text Available The mechanisms that coordinate the termination of DNA replication with progression through mitosis are not completely understood. The human Timeless protein (Tim associates with S phase replication checkpoint proteins Claspin and Tipin, and plays an important role in maintaining replication fork stability at physical barriers, like centromeres, telomeres and ribosomal DNA repeats, as well as at termination sites. We show here that human Tim can be isolated in a complex with mitotic entry kinases CDK1, Auroras A and B, and Polo-like kinase (Plk1. Plk1 bound Tim directly and colocalized with Tim at a subset of mitotic structures in M phase. Tim depletion caused multiple mitotic defects, including the loss of sister-chromatid cohesion, loss of mitotic spindle architecture, and a failure to exit mitosis. Tim depletion caused a delay in mitotic kinase activity in vivo and in vitro, as well as a reduction in global histone H3 S10 phosphorylation during G2/M phase. Tim was also required for the recruitment of Plk1 to centromeric DNA and formation of catenated DNA structures at human centromere alpha satellite repeats. Taken together, these findings suggest that Tim coordinates mitotic kinase activation with termination of DNA replication.

  8. Cardiac Troponin T and Creatine Kinase MB Fraction Levels Among ...

    African Journals Online (AJOL)

    Background: Stroke has been a global burden, with increasing morbidity and mortality. Serum cardiac troponin t (cTnT) and creatine kinase (CK-MB) fraction are reported to be elevated in patients admitted with acute ischaemic stroke and high level of these biomarkers indicated more severe stroke and neurologic deficit in ...

  9. Cardiac Troponin T and Creatine Kinase MB Fraction Levels Among ...

    African Journals Online (AJOL)

    2018-01-30

    Jan 30, 2018 ... Background: Stroke has been a global burden, with increasing morbidity and mortality. Serum cardiac troponin t (cTnT) and creatine kinase (CK‑MB) fraction are reported to be elevated in patients admitted with acute ischaemic stroke and high level of these biomarkers indicated more severe stroke and ...

  10. Periodontal status and serum creatine kinase levels among young ...

    African Journals Online (AJOL)

    Objectives: It is hypothesized that soccer players with periodontal disease exhibit raised serum creatine kinase (CK) levels as compared to those without periodontal disease. We assessed the clinical gingival status and serum CK levels among young soccer players. Materials and Methods: Demographic data were ...

  11. Changes in neutrophil count, creatine kinases and muscle soreness ...

    African Journals Online (AJOL)

    Objective. A primary objective was to examine circulating neutrophil count after repeated bouts of downhill running. An additional aim was to determine creatine kinase (CK) levels during the initial 12 hours, after repeated DHRs. Design. Eleven healthy, untrained Caucasian males performed 2 x 60 min bouts of DHR ...

  12. New monoclonal antibody against carp sperm creatine kinase

    Czech Academy of Sciences Publication Activity Database

    Koubek, Pavel; Elzeinová, Fatima; Linhart, O.; Pěknicová, Jana

    2005-01-01

    Roč. 54, č. 3 (2005), s. 154 ISSN 0271-7352. [European Congress of Reproductive Immunology /3./. 05.09.11-05.09.15, Essex] R&D Projects: GA ČR(CZ) GA524/03/0178 Institutional research plan: CEZ:AV0Z50520514 Keywords : monoclonal antibody * carp sperm * creatine kinase Subject RIV: EB - Genetics ; Molecular Biology

  13. Differences in muscle pain and plasma creatine kinase activity after ...

    African Journals Online (AJOL)

    Objective. The aim of this study was to compare the acute changes in muscle pain and plasma creatine kinase (CK) activity following the 'up' and 'down' Comrades marathon. Design. This was a quasi-experimental design. Eleven male runners (39.7±9.3 years) completed the 'up' Comrades marathon, and 11 male runners ...

  14. Cloning, expression and purification of cold adapted acetate kinase ...

    African Journals Online (AJOL)

    shell) Neobuccinum living in the Antarctic ice-covered sea. An open reading frame of 1203 bp, coding for acetate kinase gene, called ack, was amplified, cloned into the expression vector, pETY-16b, and the enzyme was overproduced by ...

  15. Assessment of creatine kinase and lactate dehydrogenase activities ...

    African Journals Online (AJOL)

    Ina bid to investigate the influence of menopausal on coronary heart disease, plasma creatine kinase (CK) and lactate dehydrogenase (LDH) enzymes were analysed on a prospective cohort of 100 women attending Irrua Specialist Teaching Hospital (ISTH), Irrua, Edo state-Nigeria. They were divided into two groups; ...

  16. Sphingosine kinase and sphingosine-1-phosphate in liver pathobiology.

    Science.gov (United States)

    Rohrbach, Timothy; Maceyka, Michael; Spiegel, Sarah

    2017-10-01

    Over 20 years ago, sphingosine-1-phosphate (S1P) was discovered to be a bioactive signaling molecule. Subsequent studies later identified two related kinases, sphingosine kinase 1 and 2, which are responsible for the phosphorylation of sphingosine to S1P. Many stimuli increase sphingosine kinase activity and S1P production and secretion. Outside the cell, S1P can bind to and activate five S1P-specific G protein-coupled receptors (S1PR1-5) to regulate many important cellular and physiological processes in an autocrine or paracrine manner. S1P is found in high concentrations in the blood where it functions to control vascular integrity and trafficking of lymphocytes. Obesity increases blood S1P levels in humans and mice. With the world wide increase in obesity linked to consumption of high-fat, high-sugar diets, S1P is emerging as an accomplice in liver pathobiology, including acute liver failure, metabolic syndrome, control of blood lipid and glucose homeostasis, nonalcoholic fatty liver disease, and liver fibrosis. Here, we review recent research on the importance of sphingosine kinases, S1P, and S1PRs in liver pathobiology, with a focus on exciting insights for new therapeutic modalities that target S1P signaling axes for a variety of liver diseases.

  17. VHH Activators and Inhibitors for Protein Kinase C Epsilon

    NARCIS (Netherlands)

    Summanen, M.M.I.

    2012-01-01

    Protein kinase C epsilon (PKCε), which is one of the novel PKC isozymes, is widely expressed throughout the body and has important roles in the function of the nervous, cardiovascular and immune systems. In order to better understand PKCε regulated pathways, isozyme specific activity modulators are

  18. PIM kinases as therapeutic targets against advanced melanoma

    Science.gov (United States)

    Shannan, Batool; Watters, Andrea; Chen, Quan; Mollin, Stefan; Dörr, Markus; Meggers, Eric; Xu, Xiaowei; Gimotty, Phyllis A.; Perego, Michela; Li, Ling; Benci, Joseph; Krepler, Clemens; Brafford, Patricia; Zhang, Jie; Wei, Zhi; Zhang, Gao; Liu, Qin; Yin, Xiangfan; Nathanson, Katherine L.; Herlyn, Meenhard; Vultur, Adina

    2016-01-01

    Therapeutic strategies for the treatment of metastatic melanoma show encouraging results in the clinic; however, not all patients respond equally and tumor resistance still poses a challenge. To identify novel therapeutic targets for melanoma, we screened a panel of structurally diverse organometallic inhibitors against human-derived normal and melanoma cells. We observed that a compound that targets PIM kinases (a family of Ser/Thr kinases) preferentially inhibited melanoma cell proliferation, invasion, and viability in adherent and three-dimensional (3D) melanoma models. Assessment of tumor tissue from melanoma patients showed that PIM kinases are expressed in pre- and post-treatment tumors, suggesting PIM kinases as promising targets in the clinic. Using knockdown studies, we showed that PIM1 contributes to melanoma cell proliferation and tumor growth in vivo; however, the presence of PIM2 and PIM3 could also influence the outcome. The inhibition of all PIM isoforms using SGI-1776 (a clinically-available PIM inhibitor) reduced melanoma proliferation and survival in preclinical models of melanoma. This was potentiated in the presence of the BRAF inhibitor PLX4720 and in the presence of PI3K inhibitors. Our findings suggest that PIM inhibitors provide promising additions to the targeted therapies available to melanoma patients. PMID:27448973

  19. Targeting protein kinases to reverse multidrug resistance in sarcoma.

    Science.gov (United States)

    Chen, Hua; Shen, Jacson; Choy, Edwin; Hornicek, Francis J; Duan, Zhenfeng

    2016-02-01

    Sarcomas are a group of cancers that arise from transformed cells of mesenchymal origin. They can be classified into over 50 subtypes, accounting for approximately 1% of adult and 15% of pediatric cancers. Wide surgical resection, radiotherapy, and chemotherapy are the most common treatments for the majority of sarcomas. Among these therapies, chemotherapy can palliate symptoms and prolong life for some sarcoma patients. However, sarcoma cells can have intrinsic or acquired resistance after treatment with chemotherapeutics drugs, leading to the development of multidrug resistance (MDR). MDR attenuates the efficacy of anticancer drugs and results in treatment failure for sarcomas. Therefore, overcoming MDR is an unmet need for sarcoma therapy. Certain protein kinases demonstrate aberrant expression and/or activity in sarcoma cells, which have been found to be involved in the regulation of sarcoma cell progression, such as cell cycle, apoptosis, and survival. Inhibiting these protein kinases may not only decrease the proliferation and growth of sarcoma cells, but also reverse their resistance to chemotherapeutic drugs to subsequently reduce the doses of anticancer drugs and decrease drug side-effects. The discovery of novel strategies targeting protein kinases opens a door to a new area of sarcoma research and provides insight into the mechanisms of MDR in chemotherapy. This review will focus on the recent studies in targeting protein kinase to reverse chemotherapeutic drug resistance in sarcoma. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Adenosine monophosphate-activated protein kinase from the mud ...

    Indian Academy of Sciences (India)

    2016-12-01

    Dec 1, 2016 ... ... Journal of Genetics; Volume 95; Issue 4. Adenosine monophosphate-activated protein kinase from the mud crab, Scylla paramamosain: cDNA cloning and profiles under cold stress. CHENCUI HUANG KUN YU HUIYANG HUANG HAIHUI YE. RESEARCH ARTICLE Volume 95 Issue 4 December 2016 pp ...

  1. Isolated and contiguous glycerol kinase gene disorders: a review

    NARCIS (Netherlands)

    Sjarif, D. R.; Ploos van Amstel, J. K.; Duran, M.; Beemer, F. A.; Poll-The, B. T.

    2000-01-01

    Glycerol kinase deficiency (GKD) is an X-linked recessive disorder. There are two types. an isolated form and a complex form. We review the clinical, biochemical and molecular genetic features of GKD. The clinical and biochemical phenotype of isolated GKD may vary from a life-threatening childhood

  2. Side-effects of protein kinase inhibitors on ion channels

    Indian Academy of Sciences (India)

    2013-11-06

    Nov 6, 2013 ... In fact, the side-effects have precluded these inhibitors from being both useful experimental tools and therapeutically viable. ... protein kinases both for experimental tools and for therapeutic approaches. [Son YK, Park H, Firth AL ...... of MAPK-activated proteins by MAPK controls the expression of various ...

  3. Serum creatine kinase and lactate dehydrogenase activities in ...

    African Journals Online (AJOL)

    Background and Objectives: There is the recognition of a pattern of elevations of serum enzymes in hyperthyroid and hypothyroid patients. The aims of this study were to determine the activities of serum creatine kinase (CK) and lactate deydrogenase (LDH) in thyroid disorders, and to evaluate the relationship between CK, ...

  4. Serum creatine kinase and lactate dehydrogenase activities in ...

    African Journals Online (AJOL)

    P = 0.002). Conclusion: The significant elevation in serum CK and LDH activities indicates that these can be used as parameters for screening hypothyroid patients but not hyperthyroid patients. Key words: Hyperthyroidism, hypothyroidism, lactate dehydrogenase, serum creatine kinase. Date of Acceptance: 28-Aug-2011.

  5. Metazoan-like signaling in a unicellular receptor tyrosine kinase

    Directory of Open Access Journals (Sweden)

    Schultheiss Kira P

    2013-02-01

    Full Text Available Abstract Background Receptor tyrosine kinases (RTKs are crucial components of signal transduction systems in multicellular animals. Surprisingly, numerous RTKs have been identified in the genomes of unicellular choanoflagellates and other protists. Here, we report the first biochemical study of a unicellular RTK, namely RTKB2 from Monosiga brevicollis. Results We cloned, expressed, and purified the RTKB2 kinase, and showed that it is enzymatically active. The activity of RTKB2 is controlled by autophosphorylation, as in metazoan RTKs. RTKB2 possesses six copies of a unique domain (designated RM2 in its C-terminal tail. An isolated RM2 domain (or a synthetic peptide derived from the RM2 sequence served as a substrate for RTKB2 kinase. When phosphorylated, the RM2 domain bound to the Src homology 2 domain of MbSrc1 from M. brevicollis. NMR structural studies of the RM2 domain indicated that it is disordered in solution. Conclusions Our results are consistent with a model in which RTKB2 activation stimulates receptor autophosphorylation within the RM2 domains. This leads to recruitment of Src-like kinases (and potentially other M. brevicollis proteins and further phosphorylation, which may serve to increase or dampen downstream signals. Thus, crucial features of signal transduction circuitry were established prior to the evolution of metazoans from their unicellular ancestors.

  6. Structural comparison of human mammalian ste20-like kinases.

    Directory of Open Access Journals (Sweden)

    Christopher J Record

    2010-08-01

    Full Text Available The serine/threonine mammalian Ste-20 like kinases (MSTs are key regulators of apoptosis, cellular proliferation as well as polarization. Deregulation of MSTs has been associated with disease progression in prostate and colorectal cancer. The four human MSTs are regulated differently by C-terminal regions flanking the catalytic domains.We have determined the crystal structure of kinase domain of MST4 in complex with an ATP-mimetic inhibitor. This is the first structure of an inactive conformation of a member of the MST kinase family. Comparison with active structures of MST3 and MST1 revealed a dimeric association of MST4 suggesting an activation loop exchanged mechanism of MST4 auto-activation. Together with a homology model of MST2 we provide a comparative analysis of the kinase domains for all four members of the human MST family.The comparative analysis identified new structural features in the MST ATP binding pocket and has also defined the mechanism for autophosphorylation. Both structural features may be further explored for inhibitors design.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1.

  7. Adenosine monophosphate-activated protein kinase from the mud ...

    Indian Academy of Sciences (India)

    CHENCUI HUANG

    Adenosine monophosphate-activated protein kinase from the mud crab, Scylla paramamosain: cDNA cloning and profiles under cold stress. CHENCUI HUANG1, KUN YU1, HUIYANG HUANG1,2 and HAIHUI YE1,2∗. 1College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, People's Republic of China.

  8. Molecular cloning and characterization of a novel human kinase ...

    Indian Academy of Sciences (India)

    Unknown

    Molecular cloning and characterization of a novel human kinase gene, PDIK1L. LINGCHEN GUO, CHAONENG JI, SHAOHUA GU, KANG YING, HAIPENG CHENG,. XIAOGHUA NI, JIANPING LIU, YI XIE and YUMIN MAO*. State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences,.

  9. Adenosine monophosphate-activated protein kinase from the mud ...

    Indian Academy of Sciences (India)

    2016-12-01

    Dec 1, 2016 ... to the understanding of the molecular mechanism of acclimation to cold hardiness in S. paramamosain. [Huang C., Yu K., Huang H. and Ye H. 2016 Adenosine monophosphate-activated protein kinase from the mud crab, Scylla paramamosain: cDNA cloning and profiles under cold stress. J. Genet.

  10. An active form of calcium and calmodulin dependant protein kinase ...

    African Journals Online (AJOL)

    The removal of the auto-inhibitory domain that negatively regulates the kinase activity in M. truncatula results in a constitutively-active form, inducing symbiotic responses in the absence of bacterial signals. In this study, we verified the functionality of a DMI3 variant and its ability to induce spontaneous nodules in M.

  11. Molecular pharmacokinetic determinants of anticancer kinase inhibitors in humans

    Directory of Open Access Journals (Sweden)

    Julie Scholler

    2011-06-01

    Full Text Available This review presents the published data regarding the molecular determinants (drug metabolizing enzymes, drug transporters and orphan nuclear receptors of approved anticancer kinase inhibitors pharmacokinetics in humans. The clinical impact of these determinants (drug disposition and drug–drug interactions is also discussed.

  12. The crystal structure of the phosphatidylinositol 4-kinase II alpha

    Czech Academy of Sciences Publication Activity Database

    Bäumlová, Adriana; Chalupská, Dominika; Rozycki, B.; Jovic, M.; Wisniewski, E.; Klíma, Martin; Dubánková, Anna; Kloer, D. P.; Nencka, Radim; Balla, T.; Bouřa, Evžen

    2014-01-01

    Roč. 15, č. 10 (2014), s. 1085-1092 ISSN 1469-221X R&D Projects: GA MŠk LO1302 EU Projects: European Commission(XE) 333916 - STARPI4K Institutional support: RVO:61388963 Keywords : crystal structure * kinase * membrane * Monte Carlo simulations * phosphatidyl inositol Subject RIV: CE - Biochemistry Impact factor: 9.055, year: 2014

  13. Isoform Specificity of Protein Kinase Cs in Synaptic Plasticity

    Science.gov (United States)

    Sossin, Wayne S.

    2007-01-01

    Protein kinase Cs (PKCs) are implicated in many forms of synaptic plasticity. However, the specific isoform(s) of PKC that underlie(s) these events are often not known. We have used "Aplysia" as a model system in order to investigate the isoform specificity of PKC actions due to the presence of fewer isoforms and a large number of documented…

  14. Evaluation of Creatine Kinase Activity and Inorganic Phosphate ...

    African Journals Online (AJOL)

    Background: Biochemical parameters vary in subjects with different hemoglobin phenotypes, compared with normal controls. Aim: The aim was to evaluate serum creatine kinase (CK) activity and inorganic phosphate concentrations in Nigerian adults with homozygous and heterozygous hemoglobin phenotypes. Subjects ...

  15. Skeletal muscle mitogen-activated protein kinases and ribosomal S6 kinases. Suppression in chronic diabetic rats and reversal by vanadium.

    Science.gov (United States)

    Hei, Y J; Chen, X; Pelech, S L; Diamond, J; McNeill, J H

    1995-10-01

    The mitogen-activated protein (MAP) kinases and ribosomal S6 protein kinases in the skeletal muscle of insulin-resistant long-term (2 and 6 months' duration) diabetic rats were investigated to understand further the changes in insulin intracellular signaling pathways that accompany diabetes. The effects of insulin-mimetic vanadium compounds on the activity of these kinases were also examined. In the insulin-resistant 2-month diabetic rats, the basal activities of MAP kinases were relatively unchanged, while the basal activities of S6 kinases were significantly increased. Intravenous injection of insulin moderately activated both the 42-kDa MAP kinase (p42mapk) and a 44-kDa MAP kinase (p44erk1) in the 2-month control rats but not in the 2-month diabetic rats. Insulin treatment markedly stimulated the activity of a novel 31-kDa S6 kinase and the previously described 90-kDa ribosomal S6 kinase encoded by one of the rsk genes (p90rsk) in the 2-month control rats, while the effect was substantially reduced in the diabetic rats. In the 6-month diabetic rats, the basal phosphotransferase activities of both MAP kinases were depressed threefold or greater. This correlated with reductions in the amount of immunoreactive p42mapk and p44erk1 proteins in extracts from the diabetic rats. The basal activity of the 31-kDa S6 kinase activity was also reduced fourfold in the 6-month diabetic rats. Treatment of the 2-month diabetic rats with vanadyl sulfate resulted in euglycemia, prevented the increase in the basal activity of S6 kinase, and improved the activation of S6 kinase by insulin.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Bi-local holography in the SYK model: perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Jevicki, Antal; Suzuki, Kenta [Department of Physics, Brown University,182 Hope Street, Providence, RI 02912 (United States)

    2016-11-08

    We continue the study of the Sachdev-Ye-Kitaev model in the Large N limit. Following our formulation in terms of bi-local collective fields with dynamical reparametrization symmetry, we perform perturbative calculations around the conformal IR point. These are based on an ε expansion which allows for analytical evaluation of correlators and finite temperature quantities.

  17. An Arabidopsis kinase cascade influences auxin-responsive cell expansion.

    Science.gov (United States)

    Enders, Tara A; Frick, Elizabeth M; Strader, Lucia C

    2017-10-01

    Mitogen-activated protein kinase (MPK) cascades are conserved mechanisms of signal transduction across eukaryotes. Despite the importance of MPK proteins in signaling events, specific roles for many Arabidopsis MPK proteins remain unknown. Multiple studies have suggested roles for MPK signaling in a variety of auxin-related processes. To identify MPK proteins with roles in auxin response, we screened mpk insertional alleles and identified mpk1-1 as a mutant that displays hypersensitivity in auxin-responsive cell expansion assays. Further, mutants defective in the upstream MAP kinase kinase MKK3 also display hypersensitivity in auxin-responsive cell expansion assays, suggesting that this MPK cascade affects auxin-influenced cell expansion. We found that MPK1 interacts with and phosphorylates ROP BINDING PROTEIN KINASE 1 (RBK1), a protein kinase that interacts with members of the Rho-like GTPases from Plants (ROP) small GTPase family. Similar to mpk1-1 and mkk3-1 mutants, rbk1 insertional mutants display auxin hypersensitivity, consistent with a possible role for RBK1 downstream of MPK1 in influencing auxin-responsive cell expansion. We found that RBK1 directly phosphorylates ROP4 and ROP6, supporting the possibility that RBK1 effects on auxin-responsive cell expansion are mediated through phosphorylation-dependent modulation of ROP activity. Our data suggest a MKK3 • MPK1 • RBK1 phosphorylation cascade that may provide a dynamic module for altering cell expansion. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  18. Two distinct functions for PI3-kinases in macropinocytosis.

    Science.gov (United States)

    Hoeller, Oliver; Bolourani, Parvin; Clark, Jonathan; Stephens, Len R; Hawkins, Phillip T; Weiner, Orion D; Weeks, Gerald; Kay, Robert R

    2013-09-15

    Class-1 PI3-kinases are major regulators of the actin cytoskeleton, whose precise contributions to chemotaxis, phagocytosis and macropinocytosis remain unresolved. We used systematic genetic ablation to examine this question in growing Dictyostelium cells. Mass spectroscopy shows that a quintuple mutant lacking the entire genomic complement of class-1 PI3-kinases retains only 10% of wild-type PtdIns(3,4,5)P3 levels. Chemotaxis to folate and phagocytosis of bacteria proceed normally in the quintuple mutant but macropinocytosis is abolished. In this context PI3-kinases show specialized functions, only one of which is directly linked to gross PtdIns(3,4,5)P3 levels: macropinosomes originate in patches of PtdIns(3,4,5)P3, with associated F-actin-rich ruffles, both of which depend on PI3-kinase 1/2 (PI3K1/2) but not PI3K4, whereas conversion of ruffles into vesicles requires PI3K4. A biosensor derived from the Ras-binding domain of PI3K1 suggests that Ras is activated throughout vesicle formation. Binding assays show that RasG and RasS interact most strongly with PI3K1/2 and PI3K4, and single mutants of either Ras have severe macropinocytosis defects. Thus, the fundamental function of PI3-kinases in growing Dictyostelium cells is in macropinocytosis where they have two distinct functions, supported by at least two separate Ras proteins.

  19. A Grammar Inference Approach for Predicting Kinase Specific Phosphorylation Sites

    Science.gov (United States)

    Datta, Sutapa; Mukhopadhyay, Subhasis

    2015-01-01

    Kinase mediated phosphorylation site detection is the key mechanism of post translational mechanism that plays an important role in regulating various cellular processes and phenotypes. Many diseases, like cancer are related with the signaling defects which are associated with protein phosphorylation. Characterizing the protein kinases and their substrates enhances our ability to understand the mechanism of protein phosphorylation and extends our knowledge of signaling network; thereby helping us to treat such diseases. Experimental methods for predicting phosphorylation sites are labour intensive and expensive. Also, manifold increase of protein sequences in the databanks over the years necessitates the improvement of high speed and accurate computational methods for predicting phosphorylation sites in protein sequences. Till date, a number of computational methods have been proposed by various researchers in predicting phosphorylation sites, but there remains much scope of improvement. In this communication, we present a simple and novel method based on Grammatical Inference (GI) approach to automate the prediction of kinase specific phosphorylation sites. In this regard, we have used a popular GI algorithm Alergia to infer Deterministic Stochastic Finite State Automata (DSFA) which equally represents the regular grammar corresponding to the phosphorylation sites. Extensive experiments on several datasets generated by us reveal that, our inferred grammar successfully predicts phosphorylation sites in a kinase specific manner. It performs significantly better when compared with the other existing phosphorylation site prediction methods. We have also compared our inferred DSFA with two other GI inference algorithms. The DSFA generated by our method performs superior which indicates that our method is robust and has a potential for predicting the phosphorylation sites in a kinase specific manner. PMID:25886273

  20. Multiple Duties for Spindle Assembly Checkpoint Kinases in Meiosis.

    Science.gov (United States)

    Marston, Adele L; Wassmann, Katja

    2017-01-01

    Cell division in mitosis and meiosis is governed by evolutionary highly conserved protein kinases and phosphatases, controlling the timely execution of key events such as nuclear envelope breakdown, spindle assembly, chromosome attachment to the spindle and chromosome segregation, and cell cycle exit. In mitosis, the spindle assembly checkpoint (SAC) controls the proper attachment to and alignment of chromosomes on the spindle. The SAC detects errors and induces a cell cycle arrest in metaphase, preventing chromatid separation. Once all chromosomes are properly attached, the SAC-dependent arrest is relieved and chromatids separate evenly into daughter cells. The signaling cascade leading to checkpoint arrest depends on several protein kinases that are conserved from yeast to man. In meiosis, haploid cells containing new genetic combinations are generated from a diploid cell through two specialized cell divisions. Though apparently less robust, SAC control also exists in meiosis. Recently, it has emerged that SAC kinases have additional roles in executing accurate chromosome segregation during the meiotic divisions. Here, we summarize the main differences between mitotic and meiotic cell divisions, and explain why meiotic divisions pose special challenges for correct chromosome segregation. The less-known meiotic roles of the SAC kinases are described, with a focus on two model systems: yeast and mouse oocytes. The meiotic roles of the canonical checkpoint kinases Bub1, Mps1, the pseudokinase BubR1 (Mad3), and Aurora B and C (Ipl1) will be discussed. Insights into the molecular signaling pathways that bring about the special chromosome segregation pattern during meiosis will help us understand why human oocytes are so frequently aneuploid.

  1. Novel expression patterns of phosphatidylinositol 3-hydroxy kinase in nodulated Medicago spp. plants

    NARCIS (Netherlands)

    Hernández, L.E.; Escobar, C.; Drobak, B.K.; Bisseling, T.; Brewin, N.J.

    2004-01-01

    A cDNA clone encoding a phosphatidylinositol 3-kinase (PtdIns 3-kinase) has been characterized from Medicago truncatula, Mtpi3k, that is highly homologous to their counterparts from soybean (over 84%). The results suggest the presence of at least two genes coding PtdIns 3-kinases in M. truncatula.

  2. INHIBITING MAP KINASE ACTIVITY PREVENTS CALCIUM TRANSIENTS AND MITOSIS ENTRY IN EARLY SEA URCHIN EMBRYOS

    OpenAIRE

    Philipova, Rada; Larman, Mark G.; Leckie, Calum P.; Harrison, Patrick K.; Groigno, Laurence; Whitaker, Michael

    2005-01-01

    A transient calcium increase triggers nuclear envelope breakdown (mitosis entry) in sea urchin embryos. Cdk1/cyclin B kinase activation is also known to be required for mitosis entry. More recently MAP kinase activity has also been shown to increase during mitosis. In sea urchin embryos both kinases show a similar activation profile, peaking at the time of mitosis entry.

  3. Exclusion of acute myocardial infarction. The value of measuring creatine kinase slope

    NARCIS (Netherlands)

    Bakker, A. J.; Koelemay, M. J.; van Vlies, B.; Gorgels, J. P.; Smits, R.; Tijssen, J. G.; Haagen, F. D.

    1995-01-01

    For the exclusion (and diagnosis) of acute myocardial infarction, we studied timed sequential (slope) measurements of creatine kinase and creatine kinase-MB catalytic activity concentration, creatine kinase-MB mass concentration, troponin T and myoglobin, using data from 242 patients consecutively

  4. Staphylococcal PknB as the First Prokaryotic Representative of the Proline-Directed Kinases

    NARCIS (Netherlands)

    Miller, Malgorzata; Donat, Stefanie; Rakette, Sonja; Stehle, Thilo; Kouwen, Thijs R. H. M.; Diks, Sander H.; Dreisbach, Annette; Reilman, Ewoud; Gronau, Katrin; Becher, Doerte; Peppelenbosch, Maikel P.; van Dijl, Jan Maarten; Ohlsen, Knut

    2010-01-01

    In eukaryotic cell types, virtually all cellular processes are under control of proline-directed kinases and especially MAP kinases. Serine/threonine kinases in general were originally considered as a eukaryote-specific enzyme family. However, recent studies have revealed that orthologues of

  5. KLIFS : a knowledge-based structural database to navigate kinase-ligand interaction space

    NARCIS (Netherlands)

    van Linden, O.P.J.; Kooistra, A.J.; Leurs, R.; de Esch, I.J.P.; de Graaf, C.

    2013-01-01

    Protein kinases regulate the majority of signal transduction pathways in cells and have become important targets for the development of designer drugs. We present a systematic analysis of kinase-ligand interactions in all regions of the catalytic cleft of all 1252 human kinase-ligand cocrystal

  6. Kinase signaling cascades in the mitochondrion: a matter of life or death.

    Science.gov (United States)

    Horbinski, Craig; Chu, Charleen T

    2005-01-01

    In addition to powering energy needs of the cell, mitochondria function as pivotal integrators of cell survival/death signals. In recent years, numerous studies indicate that each of the major kinase signaling pathways can be stimulated to target the mitochondrion. These include protein kinase A, protein kinase B/Akt, protein kinase C, extracellular signal-regulated protein kinase, c-Jun N-terminal kinase, and p38 mitogen-activated protein kinase. Although most studies focus on phosphorylation of pro- and antiapoptotic proteins (BAD, Bax, Bcl-2, Bcl-xL), kinase-mediated regulation of complex I activity, anion and cation channels, metabolic enzymes, and Mn-SOD mRNA has also been reported. Recent identification of a number of scaffold proteins (AKAP, PICK, Sab) that bring specific kinases to the cytoplasmic surface of mitochondria further emphasizes the importance of mitochondrial kinase signaling. Immunogold electron microscopy, subcellular fractionation and immunofluorescence studies demonstrate the presence of kinases within subcompartments of the mitochondrion, following diverse stimuli and in neurodegenerative diseases. Given the sensitivity of these signaling pathways to reactive oxygen and nitrogen species, in situ activation of mitochondrial kinases may represent a potent reverse-signaling mechanism for communication of mitochondrial status to the rest of the cell.

  7. The prostate-derived sterile 20-like kinase (PSK) regulates microtubule organization and stability.

    Science.gov (United States)

    Mitsopoulos, Costas; Zihni, Ceniz; Garg, Ritu; Ridley, Anne J; Morris, Jonathan D H

    2003-05-16

    Sterile 20 (STE20) protein kinases, which include germinal center kinases and p21-activated protein kinases, are known to activate mitogen-activated protein kinase pathways (c-Jun NH(2)-terminal kinase, p38, or extracellular signal-regulated kinase), leading to changes in gene transcription. Some STE20s can also regulate the cytoskeleton, and we have shown that the germinal center kinase-like kinase prostate-derived STE20-like kinase (PSK) affects actin cytoskeletal organization. Here, we demonstrate that PSK colocalizes with microtubules; and that this localization is disrupted by the microtubule depolymerizing agent nocodazole. The association of PSK with microtubules results in the production of stabilized perinuclear microtubule cables that are nocodazole-resistant and contain increased levels of acetylated alpha-tubulin. Kinase-defective PSK (K57A) or the C terminus of PSK (amino acids 745-1235) lacking the kinase domain are sufficient for microtubule binding and stabilization, demonstrating that the catalytic activity of the protein is not required. The localization of PSK to microtubules occurs via its C terminus, and PSK binds and phosphorylates alpha- and beta-tubulin in vitro. The N terminus of PSK (1-940) is unable to bind or stabilize microtubules, demonstrating that PSK must associate with microtubules for their reorganization to occur. These results demonstrate that PSK interacts with microtubules and affects their organization and stability independently of PSK kinase activity.

  8. Benzoselendiazole-based responsive long-lifetime photoluminiscent probes for protein kinases

    DEFF Research Database (Denmark)

    Ekambaram, R; Enkvist, E; Manoharan, GB

    2014-01-01

    Benzoselenadiazole-containing inhibitors of protein kinases were constructed and their capability to emit phosphorescence in the kinase-bound state was established. Labelling of the inhibitors with a red fluorescent dye led to sensitive responsive photoluminescent probes for protein kinase CK2...

  9. p21WAF1/CIP1 interacts with protein kinase CK2

    DEFF Research Database (Denmark)

    Götz, C; Wagner, P; Issinger, O G

    1996-01-01

    p21WAF1/CIP1 which belongs to a class of regulatory proteins that interact with cyclin dependent kinases is a potent inhibitor of these kinases. The inhibition of the cyclin dependent kinases induces an arrest of cells in the G phase of the cell cycle. In addition p21WAF1/CIP1 associates with PCNA...

  10. Asymmetric expression of protein kinase CK2 subunits in human kidney tumors

    DEFF Research Database (Denmark)

    Stalter, G; Siemer, S; Becht, E

    1994-01-01

    of protein kinase CK2 alpha in tumors/normal tissue (T/N) was 1.58 and that of the protein kinase CK2 beta (T/N) was 2.65. The data suggest that the generally described increase in protein kinase CK2 activity in tumor cells may to some extent result from a deregulation in subunit biosynthesis or degradation...

  11. p21-activated kinase has substrate specificity similar to Acanthamoeba myosin I heavy chain kinase and activates Acanthamoeba myosin I.

    Science.gov (United States)

    Brzeska, H; Knaus, U G; Wang, Z Y; Bokoch, G M; Korn, E D

    1997-02-18

    Acanthamoeba class I myosins are unconventional, single-headed myosins that express actin-activated Mg2+-ATPase and in vitro motility activities only when a single serine or threonine in the heavy chain is phosphorylated by myosin I heavy chain kinase (MIHCK). Some other, but not most, class I myosins have the same consensus phosphorylation site sequence, and the two known class VI myosins have a phosphorylatable residue in the homologous position, where most myosins have an aspartate or glutamate residue. Recently, we found that the catalytic domain of Acanthamoeba MIHCK has extensive sequence similarity to the p21-activated kinase (PAK)/STE20 family of kinases from mammals and yeast, which are activated by small GTP-binding proteins. The physiological substrates of the PAK/STE20 kinases are not well characterized. In this paper we show that PAK1 has similar substrate specificity as MIHCK when assayed against synthetic substrates and that PAK1 phosphorylates the heavy chain (1 mol of P(i) per mol) and activates Acanthamoeba myosin I as MIHCK does. These results, together with the known involvement of Acanthamoeba myosin I, yeast myosin I, STE20, PAK, and small GTP-binding proteins in membrane- and cytoskeleton-associated morphogenetic transformations and activities, suggest that myosins may be physiological substrates for the PAK/STE20 family and thus mediators of these events.

  12. Extracellular signal-regulated kinases control expression of G protein-coupled receptor kinase 2 (GRK2)

    DEFF Research Database (Denmark)

    Theilade, Juliane; Lerche Hansen, Jakob; Haunsø, Stig

    2002-01-01

    G protein-coupled receptor kinase 2 (GRK2) phosphorylates G protein-coupled receptors resulting in uncoupling from G proteins. Receptors modulate GRK2 expression, however the mechanistic basis for this effect is largely unknown. Here we report a novel mechanism by which receptors use...

  13. Ret receptor tyrosine kinase activates extracellular signal-regulated kinase 2 in SK-N-MC cells

    NARCIS (Netherlands)

    van Weering, D. H.; Medema, J. P.; van Puijenbroek, A.; Burgering, B. M.; Baas, P. D.; Bos, J. L.

    1995-01-01

    Ret is a receptor tyrosine kinase predominantly expressed in tissue derived from the neuroectoderm and is involved in multiple endocrine neoplasia type 2A and 2B, familiar medullary thyroid carcinoma, and Hirschsprung's disease. The ligand for the receptor is still unknown. Previously, using a human

  14. Selective Cyclin-Dependent Kinase Inhibitors Discriminating between Cell Cycle and Transcriptional Kinases Future Reality or Utopia?

    Czech Academy of Sciences Publication Activity Database

    Wesierska-Gadek, J.; Kryštof, Vladimír

    2009-01-01

    Roč. 1171, - (2009), s. 228-241 ISSN 0077-8923 R&D Projects: GA ČR GA204/08/0511 Institutional research plan: CEZ:AV0Z50380511 Keywords : cell cycle * CYC202 * cyclin-dependent kinase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.670, year: 2009

  15. Protein kinase C and extracellular signal-regulated kinase regulate movement, attachment, pairing and egg release in Schistosoma mansoni.

    Directory of Open Access Journals (Sweden)

    Margarida Ressurreição

    2014-06-01

    Full Text Available Protein kinases C (PKCs and extracellular signal-regulated kinases (ERKs are evolutionary conserved cell signalling enzymes that coordinate cell function. Here we have employed biochemical approaches using 'smart' antibodies and functional screening to unravel the importance of these enzymes to Schistosoma mansoni physiology. Various PKC and ERK isotypes were detected, and were differentially phosphorylated (activated throughout the various S. mansoni life stages, suggesting isotype-specific roles and differences in signalling complexity during parasite development. Functional kinase mapping in adult worms revealed that activated PKC and ERK were particularly associated with the adult male tegument, musculature and oesophagus and occasionally with the oesophageal gland; other structures possessing detectable activated PKC and/or ERK included the Mehlis' gland, ootype, lumen of the vitellaria, seminal receptacle and excretory ducts. Pharmacological modulation of PKC and ERK activity in adult worms using GF109203X, U0126, or PMA, resulted in significant physiological disturbance commensurate with these proteins occupying a central position in signalling pathways associated with schistosome muscular activity, neuromuscular coordination, reproductive function, attachment and pairing. Increased activation of ERK and PKC was also detected in worms following praziquantel treatment, with increased signalling associated with the tegument and excretory system and activated ERK localizing to previously unseen structures, including the cephalic ganglia. These findings support roles for PKC and ERK in S. mansoni homeostasis, and identify these kinase groups as potential targets for chemotherapeutic treatments against human schistosomiasis, a neglected tropical disease of enormous public health significance.

  16. Haspin kinase regulates microtubule-organizing center clustering and stability through Aurora kinase C in mouse oocytes

    Czech Academy of Sciences Publication Activity Database

    Balboula, A. Z.; Nguyen, A. L.; Gentilello, A. S.; Quartuccio, S. M.; Drutovič, Dávid; Šolc, Petr; Schindler, K.

    2016-01-01

    Roč. 129, č. 19 (2016), s. 3648-3660 ISSN 0021-9533 R&D Projects: GA MŠk(CZ) LO1609 Institutional support: RVO:67985904 Keywords : haspin * aurora kinase * spindle * MTOC * oocyte Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.431, year: 2016

  17. Coiled-coil interactions modulate multimerization, mitochondrial binding and kinase activity of myotonic dystrophy protein kinase splice isoforms.

    NARCIS (Netherlands)

    Herpen, R.E.M.A. van; Tjeertes, J.V.; Mulders, S.A.M.; Oude Ophuis, R.J.A.; Wieringa, B.; Wansink, D.G.

    2006-01-01

    The myotonic dystrophy protein kinase polypeptide repertoire in mice and humans consists of six different splice isoforms that vary in the nature of their C-terminal tails and in the presence or absence of an internal Val-Ser-Gly-Gly-Gly motif. Here, we demonstrate that myotonic dystrophy protein

  18. Expression and Purification of PI3 Kinase {alpha} and Development of an ATP Depletion and an AlphaScreen PI3 Kinase Activity Assay

    DEFF Research Database (Denmark)

    Boldyreff, Brigitte; Rasmussen, Tine L; Jensen, Hans H

    2008-01-01

    Phosphoinositide-3-kinases are important targets for drug development because many proteins in the PI3 kinase signaling pathway are mutated, hyperactivated, or overexpressed in human cancers. Here, the authors coexpressed the human class Ia PI3 kinase p110alpha catalytic domain with an N-terminal......Phosphoinositide-3-kinases are important targets for drug development because many proteins in the PI3 kinase signaling pathway are mutated, hyperactivated, or overexpressed in human cancers. Here, the authors coexpressed the human class Ia PI3 kinase p110alpha catalytic domain with an N...... a selection of substrates, phosphatidylinositol-4, 5-biphosphate turned out to be the best substrate at a concentration of 50 microM. p110alpha/p85alpha underwent autophosphorylation most prominently at the p85alpha subunit. However, in the presence of lipid substrate, the autophosphorylation was negligible...

  19. Purification, crystallization and preliminary X-ray diffraction analysis of the kinase domain of human tousled-like kinase 2

    Energy Technology Data Exchange (ETDEWEB)

    Garrote, Ana M.; Redondo, Pilar [Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid (Spain); Montoya, Guillermo, E-mail: gmontoya@cnio.es [Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid (Spain); University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen (Denmark); Muñoz, Inés G., E-mail: gmontoya@cnio.es [Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, 28029 Madrid (Spain)

    2014-02-19

    The C-terminal kinase domain of TLK2 (a human tousled-like kinase) has been cloned and overexpressed in Escherichia coli followed by purification to homogeneity. Crystallization experiments in the presence of ATP-γ-S yielded crystals suitable for X-ray diffraction analysis belonging to two different space groups: tetragonal I4{sub 1}22 and cubic P2{sub 1}3. Tousled-like kinases (TLKs) are an evolutionarily conserved family of serine/threonine protein kinases involved in chromatin dynamics, including DNA replication and repair, transcription and chromosome segregation. The two members of the family reported in humans, namely TLK1 and TLK2, localize to the cell nucleus and are capable of forming homo- or hetero-oligomers by themselves. To characterize the role of TLK2, its C-terminal kinase domain was cloned and overexpressed in Escherichia coli followed by purification to homogeneity. Crystallization experiments in the presence of ATP-γ-S yielded crystals suitable for X-ray diffraction analysis belonging to two different space groups: tetragonal I4{sub 1}22 and cubic P2{sub 1}3. The latter produced the best diffracting crystal (3.4 Å resolution using synchrotron radiation), with unit-cell parameters a = b = c = 126.05 Å, α = β = γ = 90°. The asymmetric unit contained one protein molecule, with a Matthews coefficient of 4.59 Å{sup 3} Da{sup −1} and a solvent content of 73.23%.

  20. The Xanthomonas euvesicatoria type III effector XopAU is an active protein kinase that manipulates plant MAP kinase signaling.

    Directory of Open Access Journals (Sweden)

    Doron Teper

    2018-01-01

    Full Text Available The Gram-negative bacterium Xanthomonas euvesicatoria (Xe is the causal agent of bacterial spot disease of pepper and tomato. Xe delivers effector proteins into host cells through the type III secretion system to promote disease. Here, we show that the Xe effector XopAU, which is conserved in numerous Xanthomonas species, is a catalytically active protein kinase and contributes to the development of disease symptoms in pepper plants. Agrobacterium-mediated expression of XopAU in host and non-host plants activated typical defense responses, including MAP kinase phosphorylation, accumulation of pathogenesis-related (PR proteins and elicitation of cell death, that were dependent on the kinase activity of the effector. XopAU-mediated cell death was not dependent on early signaling components of effector-triggered immunity and was also observed when the effector was delivered into pepper leaves by Xanthomonas campestris pv. campestris, but not by Xe. Protein-protein interaction studies in yeast and in planta revealed that XopAU physically interacts with components of plant immunity-associated MAP kinase cascades. Remarkably, XopAU directly phosphorylated MKK2 in vitro and enhanced its phosphorylation at multiple sites in planta. Consistent with the notion that MKK2 is a target of XopAU, silencing of the MKK2 homolog or overexpression of the catalytically inactive mutant MKK2K99R in N. benthamiana plants reduced XopAU-mediated cell death and MAPK phosphorylation. Furthermore, yeast co-expressing XopAU and MKK2 displayed reduced growth and this phenotype was dependent on the kinase activity of both proteins. Together, our results support the conclusion that XopAU contributes to Xe disease symptoms in pepper plants and manipulates host MAPK signaling through phosphorylation and activation of MKK2.

  1. Activation of ZmMKK10, a maize mitogen-activated protein kinase kinase, induces ethylene-dependent cell death.

    Science.gov (United States)

    Chang, Ying; Yang, Hailian; Ren, Dongtao; Li, Yuan

    2017-11-01

    Mitogen-activated protein kinase (MAPK) cascades play important roles in regulating plant growth, development and stress responses. Here, we report that ZmMKK10, a maize MAP kinase kinase, positively regulates cell death. Sequence comparison to Arabidopsis MKKs has led to ZmMKK10 being classified as a group D MKK. Kinase activity analysis of recombinant ZmMKK10 showed that the Mg 2+ ion was required for its kinase activity. Transient expression of ZmMKK10 WT or ZmMKK10 DD (the active form of ZmMKK10) in maize mesophyll protoplast significantly increased the cell death rate. Inducible expression of ZmMKK10 WT or ZmMKK10 DD in Arabidopsis transgenic plants caused rapid HR-like cell death, whereas induction of ZmMKK10 KR (the inactive form of ZmMKK10) expression in transgenic plants did not yield the same phenotype. Genetic and pharmacological analysis revealed that ZmMKK10-induced cell death in transgenic plants requires the activation of Arabidopsis MPK3 and MPK6 and that it partially depended on ethylene biosynthesis. ZmMPK3 and ZmMPK7, the orthologues of Arabidopsis MPK3 and MPK6, interacted with ZmMKK10 in yeast and ZmMKK10 phosphorylated them both in vitro. Our results demonstrate that ZmMKK10 induces cell death in an ethylene-dependent manner. Furthermore, ZmMPK3 and ZmMPK7 may be the downstream MAPKs in this process. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Expression of aurora kinases: Predictor of tumor dissemination in uterine carcinosarcoma.

    Science.gov (United States)

    Han, Kyung Hee; Kim, Min A; Park, Noh Hyun

    2017-07-01

    Uterine carcinosarcoma is a rare, aggressive, and biphasic tumor. It comprises carcinomatous and sarcomatous components, and mitosis-associated factors are thought to discriminate these two lesions. Aurora kinases are mitotic enzymes that are highly expressed in uterine malignancies. To identify the clinical significance of aurora kinase expression, we performed immunohistochemistry on tissue microarrays using cores selected from areas with typical carcinomatous and sarcomatous characteristics. A total of 24 samples were included, from patients at Seoul National University Hospital diagnosed with uterine carcinosarcoma, and who undergone a staging operation between 1997 and 2012. Patients' clinical and pathological data were analyzed, and expression patterns of aurora kinases were investigated. Aurora kinases A and B were dominantly expressed in the cytoplasm, and phospho-aurora kinases A and B were expressed in the nuclei. Phospho-aurora kinase A and aurora kinase B showed significantly higher expression in the carcinomatous component (P=0.012 and 0.008). High expression of phospho-aurora kinase A was associated with lymphatic metastasis such as positive pelvic lymph node and omental involvement (P=0.012 and 0.037). Overexpression of aurora kinase B was related to vascular invasion (P=0.011). High expression of both phospho-aurora kinase A and aurora kinase B was a prognostic factor for progression-free survival in uterine carcinosarcoma (P=0.049). In conclusion, expression of aurora kinases is associated with bidirectional tumor dissemination into the lymphatic and hematogenous pathways. In addition, high expression of phospho-aurora kinase A and aurora kinase B is a predictor of progression-free survival. Therefore, inhibitors of aurora kinases might be a prospective therapeutic options for uterine carcinosarcoma.

  3. OncoPPi-informed discovery of mitogen-activated protein kinase kinase 3 as a novel binding partner of c-Myc | Office of Cancer Genomics

    Science.gov (United States)

    Mitogen-activated protein kinase kinase 3 (MKK3) is a dual threonine/tyrosine protein kinase that regulates inflammation, proliferation and apoptosis through specific phosphorylation and activation of the p38 mitogen-activated protein kinase. However, the role of MKK3 beyond p38-signaling remains elusive. Recently, we reported a protein-protein interaction (PPI) network of cancer-associated genes, termed OncoPPi, as a resource for the scientific community to generate new biological models. Analysis of the OncoPPi connectivity identified MKK3 as one of the major hub proteins in the network.

  4. The role of Tec family kinases in the regulation of T-helper-cell differentiation.

    Science.gov (United States)

    Boucheron, Nicole; Ellmeier, Wilfried

    2012-04-01

    ABSTRACT Members of the Tec kinase family (Tec, Btk, Itk, Rlk, and Bmx) play an important role during innate and adaptive immune responses, and mutations in Tec family kinases are linked with immunodeficiencies in humans and mice. Three members of the Tec kinase family are expressed in T cells (Tec, Itk, and Rlk), and biochemical and genetic studies have revealed important roles for Tec family kinases during T-cell development and in the control of T-cell function. Here the authors review the role of Tec family kinases in the regulation of T-helper-cell differentiation.

  5. Arctigenin protects against steatosis in WRL68 hepatocytes through activation of phosphoinositide 3-kinase/protein kinase B and AMP-activated protein kinase pathways.

    Science.gov (United States)

    Chen, Kung-Yen; Lin, Jui-An; Yao, Han-Yun; Hsu, An-Chih; Tai, Yu-Ting; Chen, Jui-Tai; Hsieh, Mao-Chih; Shen, Tang-Long; Hsu, Ren-Yi; Wu, Hong-Tan; Wang, Guey Horng; Ho, Bing-Ying; Chen, Yu-Pei

    2018-02-11

    Arctigenin (ATG), a lignin extracted from Arctium lappa (L.), exerts antioxidant and anti-inflammatory effects. We hypothesized that ATG exerts a protective effect on hepatocytes by preventing nonalcoholic fatty liver disease (NAFLD) progression associated with lipid oxidation-associated lipotoxicity and inflammation. We established an in vitro NAFLD cell model by using normal WRL68 hepatocytes to investigate oleic acid (OA) accumulation and the potential bioactive role of ATG. The results revealed that ATG inhibited OA-induced lipid accumulation, lipid peroxidation, and inflammation in WRL68 hepatocytes, as determined using Oil Red O staining, thiobarbituric acid reactive substance assay, and inflammation antibody array assays. Quantitative RT-PCR analysis demonstrated that ATG significantly mitigated the expression of acetylcoenzyme A carboxylase 1 and sterol regulatory element-binding protein-1 and significantly increased the expression of carnitine palmitoyltransferase 1 and peroxisome proliferator-activated receptor alpha. The 40 targets of the Human Inflammation Antibody Array indicated that ATG significantly inhibited the elevation of the U937 lymphocyte chemoattractant, ICAM-1, IL-1β, IL-6, IL-6sR, IL-7, and IL-8. ATG could activate the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) and AMP-activated protein kinase (AMPK) pathways and could increase the phosphorylation levels of Akt and AMPK to mediate cell survival, lipid metabolism, oxidation stress, and inflammation. Thus, we demonstrated that ATG could inhibit NAFLD progression associated with lipid oxidation-associated lipotoxicity and inflammation, and we provided insights into the underlying mechanisms and revealed potential targets to enable a thorough understanding of NAFLD progression. Copyright © 2017. Published by Elsevier Inc.

  6. Lindersin B from Lindernia crustacea induces neuritogenesis by activation of tyrosine kinase A/phosphatidylinositol 3 kinase/extracellular signal-regulated kinase signaling pathway.

    Science.gov (United States)

    Cheng, Lihong; Ye, Ying; Xiang, Lan; Osada, Hiroyuki; Qi, Jianhua

    2017-01-15

    Neurotrophic factors such as nerve growth factor (NGF) play important roles in nervous system. NGF is a potential therapeutic drug for treatment of neurodegenerative diseases. However, because of physicochemical property, NGF cannot pass through the blood-brain barrier (BBB). Hence, small molecules which exhibit NGF-mimic activity and can pass through the BBB are considered to be promising drug candidates for treatment of such diseases. The present study was designed to isolate NGF-mimic substance from extract of natural products, determine their structures and investigate mechanism of action of the active substance. Extract of Lindernia crustacean was partitioned between water and ethyl acetate to obtain water layer and ethyl acetate layer samples, respectively, and then evaluated their neuritogenic activity in PC12 cells. The active sample was separated by open columns, followed by HPLC purification to obtain active compound. Then, specific inhibitors were used to investigate signaling pathway of neurite outgrowth induced by the active compound. Finally, western blot analysis was performed to confirm the pathway proposed by inhibitor experiments. The ethyl acetate layer sample of extract of Lindernia crustacea exhibited significant neuritogenic activity. Two new compounds, named as linderside A and lindersin B, were isolated; their structures were elucidated by spectroscopic and chemical derivatization methods. Linderside A is a cucurbitane glycoside, whereas lindersin B is a cucurbitane triterpenoid. Each compound has an unusual isopentene unit, namely, a double bond bound to an unmodified isopropyl group at the end of cucurbitane triterpenoid side chain. Among them, lindersin B induced significant neurite outgrowth in PC12 cells, while linderside A was inactive against PC12 cells. Western blotting analysis results showed that lindersin B-induced neuritogenic activity depended on the activation of the mitogen-activated protein kinase (MAPK)/extracellular signal

  7. A kinome wide screen identifies novel kinases involved in regulation of monoamine transporter function

    DEFF Research Database (Denmark)

    Vuorenpää, Anne Elina; Ammendrup-Johnsen, Ina; Jorgensen, Trine N.

    2016-01-01

    cells (CAD) and rat chromocytoma (PC12) cells. Whereas SIK3 likely transcriptionally regulated expression of the three transfected transporters, depletion of PKA C-α was shown to decrease SERT function. Depletion of PrKX caused decreased surface expression and function of DAT without changing protein...... in regulation of monoamine transporter function and surface expression. A primary screen in HEK 293 cells stably expressing DAT or SERT with siRNAs against 573 human kinases revealed 93 kinases putatively regulating transporter function. All 93 hits, which also included kinases previously implicated...... in HEK 293 cells transiently expressing DAT, SERT or NET. Subsequently, three kinases; salt inducible kinase 3 (SIK3), cAMP-dependent protein kinase catalytic subunit alpha (PKA C-α) and protein kinase X-linked (PrKX); were selected for additional exploration in catecholaminergic CATH.a differentiated...

  8. Cyclic AMP activates the mitogen-activated protein kinase cascade in PC12 cells

    DEFF Research Database (Denmark)

    Frödin, M; Peraldi, P; Van Obberghen, E

    1994-01-01

    reported. In rat pheochromocytoma PC12 cells, we demonstrate here a stimulation of the MAP kinase isozyme extracellular signal-regulated kinase 1 (ERK1) following elevation of intracellular cAMP after exposure of the cells to isobutylmethylxanthine, cholera toxin, forskolin, or cAMP-analogues. cAMP acted...... upstream activator of ERK1 in the MAP kinase cascade. Supporting this view, forskolin and a cAMP analogue were found to increase the activity of MAP kinase kinase in PC12 cells, alone as well as in combination with phorbol ester. PACAP38 also stimulated in vivo 32P-labeling of ERK1 and MAP kinase kinase...... activity. Finally, cAMP or PACAP38 increased by 3-fold nerve growth factor-stimulated neurite formation in PC12 cells, which may be correlated with the potentiating effect of these agents on nerve growth factor-stimulated ERK1 activity....

  9. Structural basis for the regulation of maternal embryonic leucine zipper kinase.

    Directory of Open Access Journals (Sweden)

    Lu-Sha Cao

    Full Text Available MELK (maternal embryonic leucine zipper kinase, which is a member of the AMPK (AMP-activated protein kinase-related kinase family, plays important roles in diverse cellular processes and has become a promising drug target for certain cancers. However, the regulatory mechanism of MELK remains elusive. Here, we report the crystal structure of a fragment of human MELK that contains the kinase domain and ubiquitin-associated (UBA domain. The UBA domain tightly binds to the back of the kinase domain, which may contribute to the proper conformation and activity of the kinase domain. Interestingly, the activation segment in the kinase domain displays a unique conformation that contains an intramolecular disulfide bond. The structural and biochemical analyses unravel the molecular mechanisms for the autophosphorylation/activation of MELK and the dependence of its catalytic activity on reducing agents. Thus, our results may provide the basis for designing specific MELK inhibitors for cancer treatment.

  10. Regulation of AMP-activated protein kinase by LKB1 and CaMKK in adipocytes

    DEFF Research Database (Denmark)

    Gormand, Amélie; Henriksson, Emma; Ström, Kristoffer

    2011-01-01

    AMP-activated protein kinase (AMPK) is a serine/threonine kinase that regulates cellular and whole body energy homeostasis. In adipose tissue, activation of AMPK has been demonstrated in response to a variety of extracellular stimuli. However, the upstream kinase that activates AMPK in adipocytes...... remains elusive. Previous studies have identified LKB1 as a major AMPK kinase in muscle, liver, and other tissues. In certain cell types, Ca(2+) /calmodulin-dependent protein kinase kinase β (CaMKKβ) has been shown to activate AMPK in response to increases of intracellular Ca(2+) levels. Our aim...... was to investigate if LKB1 and/or CaMKK function as AMPK kinases in adipocytes. We used adipose tissue and isolated adipocytes from mice in which the expression of LKB1 was reduced to 10-20% of that of wild-type (LKB1 hypomorphic mice). We show that adipocytes from LKB1 hypomorphic mice display a 40% decrease...

  11. Selective inhibition of retinal angiogenesis by targeting PI3 kinase.

    Directory of Open Access Journals (Sweden)

    Yolanda Alvarez

    Full Text Available Ocular neovascularisation is a pathological hallmark of some forms of debilitating blindness including diabetic retinopathy, age related macular degeneration and retinopathy of prematurity. Current therapies for delaying unwanted ocular angiogenesis include laser surgery or molecular inhibition of the pro-angiogenic factor VEGF. However, targeting of angiogenic pathways other than, or in combination to VEGF, may lead to more effective and safer inhibitors of intraocular angiogenesis. In a small chemical screen using zebrafish, we identify LY294002 as an effective and selective inhibitor of both developmental and ectopic hyaloid angiogenesis in the eye. LY294002, a PI3 kinase inhibitor, exerts its anti-angiogenic effect in a dose-dependent manner, without perturbing existing vessels. Significantly, LY294002 delivered by intraocular injection, significantly inhibits ocular angiogenesis without systemic side-effects and without diminishing visual function. Thus, targeting of PI3 kinase pathways has the potential to effectively and safely treat neovascularisation in eye disease.

  12. Protein Kinase C δ: a Gatekeeper of Immune Homeostasis.

    Science.gov (United States)

    Salzer, Elisabeth; Santos-Valente, Elisangela; Keller, Bärbel; Warnatz, Klaus; Boztug, Kaan

    2016-10-01

    Human autoimmune disorders present in various forms and are associated with a life-long burden of high morbidity and mortality. Many different circumstances lead to the loss of immune tolerance and often the origin is suspected to be multifactorial. Recently, patients with autosomal recessive mutations in PRKCD encoding protein kinase c delta (PKCδ) have been identified, representing a monogenic prototype for one of the most prominent forms of humoral systemic autoimmune diseases, systemic lupus erythematosus (SLE). PKCδ is a signaling kinase with multiple downstream target proteins and with functions in various signaling pathways. Interestingly, mouse models have indicated a special role of the ubiquitously expressed protein in the control of B-cell tolerance revealed by the severe autoimmunity in Prkcd (-/-) knockout mice as the major phenotype. As such, the study of PKCδ deficiency in humans has tremendous potential in enhancing our knowledge on the mechanisms of B-cell tolerance.

  13. Sensitization of TRPA1 by Protein Kinase A.

    Directory of Open Access Journals (Sweden)

    Jannis E Meents

    Full Text Available The TRPA1 ion channel is expressed in nociceptive (pain-sensitive somatosensory neurons and is activated by a wide variety of chemical irritants, such as acrolein in smoke or isothiocyanates in mustard. Here, we investigate the enhancement of TRPA1 function caused by inflammatory mediators, which is thought to be important in lung conditions such as asthma and COPD. Protein kinase A is an important kinase acting downstream of inflammatory mediators to cause sensitization of TRPA1. By using site-directed mutagenesis, patch-clamp electrophysiology and calcium imaging we identify four amino acid residues, S86, S317, S428, and S972, as the principal targets of PKA-mediated phosphorylation and sensitization of TRPA1.

  14. Photoactivatable Caged Prodrugs of VEGFR-2 Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Boris Pinchuk

    2016-04-01

    Full Text Available In this study, we report on the design, synthesis, photokinetic properties and in vitro evaluation of photoactivatable caged prodrugs for the receptor tyrosine kinase VEGFR-2. Highly potent VEGFR-2 inhibitors 1 and 3 were caged by introduction of a photoremovable protecting group (PPG to yield the caged prodrugs 4 and 5. As expected, enzymatic and cellular proliferation assays showed dramatically diminished efficacy of caged prodrugs in vitro. Upon ultraviolet (UV irradiation of the prodrugs original inhibitory activity was completely restored and even distinctly reinforced, as was the case for the prodrug 4. The presented results are a further evidence for caging technique being an interesting approach in the protein kinase field. It could enable spatial and temporal control for the inhibition of VEGFR-2. The described photoactivatable prodrugs might be highly useful as biological probes for studying the VEGFR-2 signal transduction.

  15. Signal Transduction in Histidine Kinases: Insights from New Structures

    Science.gov (United States)

    Bhate, Manasi P.; Molnar, Kathleen S.; Goulian, Mark; DeGrado, William F.

    2015-01-01

    Histidine kinases (HKs) are major players in bacterial signaling. There has been an explosion of new HK crystal structures in the last five years. We globally analyze the structures of HKs to yield insights into the mechanisms by which signals are transmitted to and across protein structures in this family. We interpret known enzymological data in the context of new structural data to show how asymmetry across the dimer interface is a key feature of signal transduction in HKs, and discuss how different HK domains undergo asymmetric-to-symmetric transitions during signal transduction and catalysis. A thermodynamic framework for signaling that encompasses these various properties is presented and the consequences of weak thermodynamic coupling are discussed. The synthesis of observations from enzymology, structural biology, protein engineering and thermodynamics paves the way for a deeper molecular understanding of histidine kinase signal transduction. PMID:25982528

  16. Directing the use of DDR kinase inhibitors in cancer treatment.

    Science.gov (United States)

    Brandsma, Inger; Fleuren, Emmy D G; Williamson, Chris T; Lord, Christopher J

    2017-12-01

    Defects in the DNA damage response (DDR) drive the development of cancer by fostering DNA mutation but also provide cancer-specific vulnerabilities that can be exploited therapeutically. The recent approval of three different PARP inhibitors for the treatment of ovarian cancer provides the impetus for further developing targeted inhibitors of many of the kinases involved in the DDR, including inhibitors of ATR, ATM, CHEK1, CHEK2, DNAPK and WEE1. Areas covered: We summarise the current stage of development of these novel DDR kinase inhibitors, and describe which predictive biomarkers might be exploited to direct their clinical use. Expert opinion: Novel DDR inhibitors present promising candidates in cancer treatment and have the potential to elicit synthetic lethal effects. In order to fully exploit their potential and maximize their utility, identifying highly penetrant predictive biomarkers of single agent and combinatorial DDR inhibitor sensitivity are critical. Identifying the optimal drug combination regimens that could used with DDR inhibitors is also a key objective.

  17. Protein kinase C involvement in focal adhesion formation

    DEFF Research Database (Denmark)

    Woods, A; Couchman, J R

    1992-01-01

    Matrix molecules such as fibronectin can promote cell attachment, spreading and focal adhesion formation. Although some interactions of fibronectin with cell surface receptors have now been identified, the consequent activation of intracellular messenger systems by cell/matrix interactions have...... still to be elucidated. We show here that the kinase inhibitors H7 and HA1004 reduce focal adhesion and stress fiber formation in response to fibronectin in a dose-dependent manner, and that activators of protein kinase C can promote their formation under conditions where they do not normally form....... Fibroblasts spread within 1h on substrata composed of fibronectin and formed focal adhesions by 3h, as monitored by interference reflection microscopy (IRM) and by labeling for talin, vinculin and integrin beta 1 subunits. In addition, stress fibers were visible. When cells were allowed to spread for 1h...

  18. Mitogen Activated Protein kinase signal transduction pathways in the prostate

    Directory of Open Access Journals (Sweden)

    Koul Sweaty

    2004-06-01

    Full Text Available Abstract The biochemistry of the mitogen activated protein kinases ERK, JNK, and p38 have been studied in prostate physiology in an attempt to elucidate novel mechanisms and pathways for the treatment of prostatic disease. We reviewed articles examining mitogen-activated protein kinases using prostate tissue or cell lines. As with other tissue types, these signaling modules are links/transmitters for important pathways in prostate cells that can result in cellular survival or apoptosis. While the activation of the ERK pathway appears to primarily result in survival, the roles of JNK and p38 are less clear. Manipulation of these pathways could have important implications for the treatment of prostate cancer and benign prostatic hypertrophy.

  19. MAP Kinase 4 Substrates and Plant Innate Immunity

    DEFF Research Database (Denmark)

    Rasmussen, Magnus Wohlfahrt

    recognition, which also induce its localization to cytoplasmic processing bodies. All three proteins; PAT1, AOC3 and eIF4E also interacts with MPK4 in vivo although the functional outcome of these interactions are still elusive. The thesis comprise a general introduction to plant innate immunity followed...... by two review articles “MAP kinase cascades in Arabidopsis innate immunity” published in Frontiers in Plant Science and “mRNA decay in plant immunity” under revision for Cellular and Molecular Life Science. Together these sections gives a comprehensive overview of Arabidopsis defense signaling......Multi-layered defense responses are activated in plants upon recognition of invading pathogens. Transmembrane receptors recognize conserved pathogen-associated molecular patterns and activate MAP kinase cascades, which regulate changes in gene expression to produce appropriate immune responses...

  20. Novel links in the plant TOR kinase signaling network.

    Science.gov (United States)

    Xiong, Yan; Sheen, Jen

    2015-12-01

    Nutrient and energy sensing and signaling mechanisms constitute the most ancient and fundamental regulatory networks to control growth and development in all life forms. The target of rapamycin (TOR) protein kinase is modulated by diverse nutrient, energy, hormone and stress inputs and plays a central role in regulating cell proliferation, growth, metabolism and stress responses from yeasts to plants and animals. Recent chemical, genetic, genomic and metabolomic analyses have enabled significant progress toward molecular understanding of the TOR signaling network in multicellular plants. This review discusses the applications of new chemical tools to probe plant TOR functions and highlights recent findings and predictions on TOR-mediate biological processes. Special focus is placed on novel and evolutionarily conserved TOR kinase effectors as positive and negative signaling regulators that control transcription, translation and metabolism to support cell proliferation, growth and maintenance from embryogenesis to senescence in the plant system. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Receptor tyrosine kinase structure and function in health and disease

    Directory of Open Access Journals (Sweden)

    Oleg A. Karpov

    2015-09-01

    Full Text Available Receptor tyrosine kinases (RTKs are membrane proteins that control the flow of information through signal transduction pathways, impacting on different aspects of cell function. RTKs are characterized by a ligand-binding ectodomain, a single transmembrane α-helix, a cytosolic region comprising juxtamembrane and kinase domains followed by a flexible C-terminal tail. Somatic and germline RTK mutations can induce aberrant signal transduction to give rise to cardiovascular, developmental and oncogenic abnormalities. RTK overexpression occurs in certain cancers, correlating signal strength and disease incidence. Diverse RTK activation and signal transduction mechanisms are employed by cells during commitment to health or disease. Small molecule inhibitors are one means to target RTK function in disease initiation and progression. This review considers RTK structure, activation, and signal transduction and evaluates biological relevance to therapeutics and clinical outcomes.

  2. Prolonged and tunable residence time using reversible covalent kinase inhibitors.

    Science.gov (United States)

    Bradshaw, J Michael; McFarland, Jesse M; Paavilainen, Ville O; Bisconte, Angelina; Tam, Danny; Phan, Vernon T; Romanov, Sergei; Finkle, David; Shu, Jin; Patel, Vaishali; Ton, Tony; Li, Xiaoyan; Loughhead, David G; Nunn, Philip A; Karr, Dane E; Gerritsen, Mary E; Funk, Jens Oliver; Owens, Timothy D; Verner, Erik; Brameld, Ken A; Hill, Ronald J; Goldstein, David M; Taunton, Jack

    2015-07-01

    Drugs with prolonged on-target residence times often show superior efficacy, yet general strategies for optimizing drug-target residence time are lacking. Here we made progress toward this elusive goal by targeting a noncatalytic cysteine in Bruton's tyrosine kinase (BTK) with reversible covalent inhibitors. Using an inverted orientation of the cysteine-reactive cyanoacrylamide electrophile, we identified potent and selective BTK inhibitors that demonstrated biochemical residence times spanning from minutes to 7 d. An inverted cyanoacrylamide with prolonged residence time in vivo remained bound to BTK for more than 18 h after clearance from the circulation. The inverted cyanoacrylamide strategy was further used to discover fibroblast growth factor receptor (FGFR) kinase inhibitors with residence times of several days, demonstrating the generalizability of the approach. Targeting of noncatalytic cysteines with inverted cyanoacrylamides may serve as a broadly applicable platform that facilitates 'residence time by design', the ability to modulate and improve the duration of target engagement in vivo.

  3. Receptor tyrosine kinases: the emerging tip of systems control.

    Science.gov (United States)

    Seger, R; Rodeck, U; Yarden, Y

    2008-01-01

    Receptor tyrosine kinases (RTKs) are transmembrane allosteric enzymes: binding of ligand growth factors to their ectodomains stimulates a cytoplasm-facing tyrosine kinase activity, which initiates a plethora of cellular processes. The enormous complexity of RTK signalling, along with rich involvement in pathologies (e.g. cancer and diabetes), motivated the establishment of the international, multi-disciplinary RTK consortium (http://www.rtkconsort.org/) in 2005. In collaboration with the British Society for Proteome Research and the European Bioinformatics Institute, the Consortium held on July 23rd and 24th a Workshop on Proteomics and Phosphoproteomics of RTK Signalling Networks (Hinxton Hall Conference Centre, Cambridge, UK). As highlighted below, systems control (a layered web of regulatory loops summarised in Fig.1) emerged throughout the workshop as a common theme of many presentations.

  4. K63-Linked Ubiquitination in Kinase Activation and Cancer

    International Nuclear Information System (INIS)

    Wang, Guocan; Gao, Yuan; Li, Liren; Jin, Guoxiang; Cai, Zhen; Chao, Jui-I; Lin, Hui-Kuan

    2012-01-01

    Ubiquitination has been demonstrated to play a pivotal role in multiple biological functions, which include cell growth, proliferation, apoptosis, DNA damage response, innate immune response, and neuronal degeneration. Although the role of ubiquitination in targeting proteins for proteasome-dependent degradation have been extensively studied and well-characterized, the critical non-proteolytic functions of ubiquitination, such as protein trafficking and kinase activation, involved in cell survival and cancer development, just start to emerge, In this review, we will summarize recent progresses in elucidating the non-proteolytic function of ubiquitination signaling in protein kinase activation and its implications in human cancers. The advancement in the understanding of the novel functions of ubiquitination in signal transduction pathways downstream of growth factor receptors may provide novel paradigms for the treatment of human cancers.

  5. Stress signaling by Tec tyrosine kinase in the ischemic myocardium.

    Science.gov (United States)

    Zhang, Michael J; Franklin, Sarah; Li, Yifeng; Wang, Sujing; Ru, Xiaochen; Mitchell-Jordan, Scherise A; Mano, Hiroyuki; Stefani, Enrico; Ping, Peipei; Vondriska, Thomas M

    2010-09-01

    Nonreceptor tyrosine kinases have an increasingly appreciated role in cardiac injury and protection. To investigate novel tasks for members of the Tec family of nonreceptor tyrosine kinases in cardiac phenotype, we examined the behavior of the Tec isoform in myocardial ischemic injury. Ischemia-reperfusion, but not cardiac protective agents, induced altered intracellular localization of Tec, highlighting distinct actions of this protein compared with other isoforms, such as Bmx, in the same model. Tec is abundantly expressed in cardiac myocytes and assumes a diffuse intracellular localization under basal conditions but is recruited to striated structures upon various stimuli, including ATP. To characterize Tec signaling targets in vivo, we performed an exhaustive proteomic analysis of Tec-binding partners. These experiments expand the role of the Tec family in the heart, identifying the Tec isoform as an ischemic injury-induced isoform, and map the subproteome of its interactors in isolated cells.

  6. Conserved family of glycerol kinase loci in Drosophila melanogaster

    Science.gov (United States)

    Martinez Agosto, Julian A.; McCabe, Edward R.B.

    2009-01-01

    Glycerol kinase (GK) is an enzyme that catalyzes the formation of glycerol 3-phosphate from ATP and glycerol, the rate-limiting step in glycerol utilization. We analyzed the genome of the model organism Drosophila melanogaster and identified five GK orthologs, including two loci with sequence homology to the mammalian Xp21 GK protein. Using a combination of sequence analysis and evolutionary comparisons of orthologs between species, we characterized functional domains in the protein required for GK activity. Our findings include additional conserved domains that suggest novel nuclear and mitochondrial functions for glycerol kinase in apoptosis and transcriptional regulation. Investigation of GK function in Drosophila will inform us about the role of this enzyme in development and will provide us with a tool to examine genetic modifiers of human metabolic disorders. PMID:16545593

  7. Emerging Roles of AMP-Activated Protein Kinase

    DEFF Research Database (Denmark)

    Fritzen, Andreas Mæchel

    The cellular energy sensor AMP-activated protein kinase (AMPK) is activated, when the energy balance of the cell decreases. AMPK has been proposed to regulate multiple metabolic processes. However, much of the evidence for these general effects of AMPK relies on investigations in cell systems...... exercise appears to inhibit pyruvate dehydrogenase (PDH) activity by an immediate up-regulation of pyruvate dehydrogenase kinase 4 (PDK4) protein content. Consequently, this may inhibit glucose oxidation and thereby generate conditions for increased FA oxidation and glycogen resynthesis in skeletal muscle...... be of importance for prioritising energy dissipation, inhibition of lipid storage pathways and regulation of mitochondrial and metabolic proteins, but this needs further investigations. In addition, we provide evidence that AMPK is regulating autophagic signalling in skeletal muscle. Thus, in skeletal muscle AMPK...

  8. Protein Kinase Pathways That Regulate Neuronal Survival and Death

    Science.gov (United States)

    2004-08-01

    radiography . The incorporation of phosphate into GSK-313 and L-pyruvate kinase addition of the stimulus. Cells that did not receive drugs received a...mesencephalon strands were x400 magnification into SlideBook digital deconvolu- made by bisecting fragments of human fetal ventral mesencephalon, tion...death technique utilized to prevent selective counting bias was that random fields were selected by two independent researchers. Ten fields contain

  9. Supplementary data: Variation in the PTEN-induced putative kinase ...

    Indian Academy of Sciences (India)

    Variation in the PTEN-induced putative kinase 1 gene associated with the increase risk of type 2 diabetes in northern Chinese. Yanchun Qu, Liang Sun, Ze Yang and Ruifa Han. J. Genet. 90, 125–128. Table 1. Clinical characteristics of cases and controls. Phenotype. T2DM. Controls. P value. Age (years). 49.5 ± 11.1. 50.4 ± ...

  10. Novel arylazopyrazole inhibitors of cyclin-dependent kinases

    Czech Academy of Sciences Publication Activity Database

    Jorda, Radek; Schütznerová, E.; Cankař, P.; Brychtová, Veronika; Navrátilová, Jana; Kryštof, Vladimír

    2015-01-01

    Roč. 23, č. 9 (2015), s. 1975-1981 ISSN 0968-0896 R&D Projects: GA ČR GAP305/12/0783; GA ČR GA14-19590S; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Cyclin-dependent kinases * Inhibitor * Cell cycle Subject RIV: CE - Biochemistry Impact factor: 2.923, year: 2015

  11. Purine analogs as phosphatidylinositol 4-kinase III beta inhibitors

    Czech Academy of Sciences Publication Activity Database

    Šála, Michal; Kögler, Martin; Plačková, Pavla; Mejdrová, Ivana; Hřebabecký, Hubert; Procházková, Eliška; Strunin, Dmytro; Lee, G.; Birkuš, G.; Weber, Jan; Mertlíková-Kaiserová, Helena; Nencka, Radim

    2016-01-01

    Roč. 26, č. 11 (2016), s. 2706-2712 ISSN 0960-894X R&D Projects: GA ČR GA15-09310S; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : phosphatidylinositol 4-kinase * purine * PI4K III beta * antiviral agent * hepatitis C virus Subject RIV: CC - Organic Chemistry Impact factor: 2.454, year: 2016

  12. Targeting SRC Family Kinases and HSP90 in Lung Cancer

    Science.gov (United States)

    2016-12-01

    United States and has adversely affected the lives of many Americans. Typically, only 16% of patients survive 5 years beyond initial diagnosis. The...8. Special Reporting Requirements 11 9. Appendices 11 Golemis, Erica -3- INTRODUCTION: Elevated activity of SRC family kinases (SFKs) and heat shock ...Training and management of personnel involved Anna Gaponova Graduate Student In vitro and in vivo experiments proposed; Mouse work Illya Serebriiskii

  13. Signal Transduction in Histidine Kinases: Insights from New Structures

    OpenAIRE

    Bhate, Manasi P.; Molnar, Kathleen S.; Goulian, Mark; DeGrado, William F.

    2015-01-01

    Histidine kinases (HKs) are major players in bacterial signaling. There has been an explosion of new HK crystal structures in the last five years. We globally analyze the structures of HKs to yield insights into the mechanisms by which signals are transmitted to and across protein structures in this family. We interpret known enzymological data in the context of new structural data to show how asymmetry across the dimer interface is a key feature of signal transduction in HKs, and discuss how...

  14. Differential sensitivity of ERBB2 kinase domain mutations towards lapatinib.

    Directory of Open Access Journals (Sweden)

    Rama Krishna Kancha

    Full Text Available BACKGROUND: Overexpression of the ERBB2 kinase is observed in about one-third of breast cancer patients and the dual ERBB1/ERBB2 kinase inhibitor lapatinib was recently approved for the treatment of advanced ERBB2-positive breast cancer. Mutations in the ERBB2 receptor have recently been reported in breast cancer at diagnosis and also in gastric, colorectal and lung cancer. These mutations may have an impact on the clinical responses achieved with lapatinib in breast cancer and may also have a potential impact on the use of lapatinib in other solid cancers. However, the sensitivity of lapatinib towards clinically observed ERBB2 mutations is not known. METHODOLOGY/PRINCIPAL FINDINGS: We cloned a panel of 8 clinically observed ERBB2 mutations, established stable cell lines and characterized their sensitivity towards lapatinib and alternative ERBB2 inhibitors. Both lapatinib-sensitive and lapatinib-resistant ERBB2 mutations were observed. Interestingly, we were able to generate lapatinib resistance mutations in wt-ERBB2 cells incubated with lapatinib for prolonged periods of time. This indicates that these resistance mutations may also cause secondary resistance in lapatinib-treated patients. Lapatinib-resistant ERBB2 mutations were found to be highly resistant towards AEE788 treatment but remained sensitive towards the dual irreversible inhibitors CL-387785 and WZ-4002. CONCLUSIONS/SIGNIFICANCE: Patients harbouring certain ERBB2 kinase domain mutations at diagnosis may not benefit from lapatinib treatment. Moreover, secondary lapatinib resistance may develop due to kinase domain mutations. Irreversible ERBB2 inhibitors may offer alternative treatment options for breast cancer and other solid tumor patients harbouring lapatinib resistance mutations. In addition, these inhibitors may be of interest in the scenario of secondary lapatinib resistance.

  15. Roles of Mitogen-Activating Protein Kinase Kinase Kinase Kinase-3 (MAP4K3) in Preterm Skeletal Muscle Satellite Cell Myogenesis and Mammalian Target of Rapamycin Complex 1 (mTORC1) Activation Regulation.

    Science.gov (United States)

    Guo, Chu-Yi; Yu, Mu-Xue; Dai, Jie-Min; Pan, Si-Nian; Lu, Zhen-Tong; Qiu, Xiao-Shan; Zhuang, Si-Qi

    2017-07-21

    BACKGROUND Preterm skeletal muscle genesis is a paradigm for myogenesis. The role of mitogen-activating protein kinase kinase kinase kinase-3 (MAP4K3) in preterm skeletal muscle satellite cells myogenesis or its relationship to mammalian target of rapamycin complex 1 (mTORC1) activity have not been previously elaborated. MATERIAL AND METHODS Small interfering RNA (siRNA) interference technology was used to inhibit MAP4K3 expression. Leucine stimulation experiments were performed following MAP4K3-siRNA interference. The differentiation of primary preterm skeletal muscle satellite cells was observed after siRNA-MAP4K3 interference. Western blot analysis was used to determine the expression of MAP4K3, MyHC, MyoD, myogenin, p-mTOR, and p-S6K1. The immunofluorescence fusion index of MyHC and myogenin were detected. MAP4K3 effects on preterm rat satellite cells differentiation and its relationship to mTORC1 activity are reported. RESULTS MAP4K3 siRNA knockdown inhibited myotube formation and both MyoD and myogenin expression in primary preterm rat skeletal muscle satellite cells, but MAP4K3 siRNA had no effect on the activity of mTORC1. In primary preterm rat skeletal muscle satellite cells, MAP4K3 knockdown resulted in significantly weaker, but not entirely blunted, leucine-induced mTORC1 signaling. CONCLUSIONS MAP4K3 positively regulates preterm skeletal muscle satellite cell myogenesis, but may not regulate mTORC1 activity. MAP4K3 may play a role in mTORC1 full activation in response to leucine.

  16. Arabidopsis MAP kinase 4 negatively regulates systemic acquired resistance

    DEFF Research Database (Denmark)

    Petersen, M.; Brodersen, P.; Naested, H.

    2000-01-01

    Transposon inactivation of Arabidopsis MAP kinase 4 produced the mpk4 mutant exhibiting constitutive systemic acquired resistance (SAR) including elevated salicylic acid (SA) revels, increased resistance to virulent pathogens, and constitutive pathogenesis-related gene expression shown by Northern...... of NPR1. PDF1.2 and THI2.1 gene induction by jasmonate was blocked in mpk4 expressing NahG, suggesting that MPK4 is required for jasmonic acid-responsive gene expression....

  17. Cyclin-dependent kinase inhibitors as anticancer drugs

    Czech Academy of Sciences Publication Activity Database

    Kryštof, Vladimír; Uldrijan, S.

    2010-01-01

    Roč. 11, č. 3 (2010), s. 291-302 ISSN 1389-4501 R&D Projects: GA ČR GA204/08/0511; GA ČR GA301/08/1649; GA MŠk(CZ) LC06077 Institutional research plan: CEZ:AV0Z50380511 Keywords : CDK * protein kinase * inhibitor Subject RIV: CE - Biochemistry Impact factor: 3.061, year: 2010

  18. Mitogen-activated protein kinases in the acute diabetic myocardium

    Czech Academy of Sciences Publication Activity Database

    Strnisková, M.; Barančík, M.; Neckář, Jan; Ravingerová, T.

    2003-01-01

    Roč. 249, 1-2 (2003), s. 59-65 ISSN 0300-8177 R&D Projects: GA MŠk LN00A069 Grant - others:VEGA(SK) 2/2063/22 Institutional research plan: CEZ:AV0Z5011922 Keywords : experimental diabetes * ischemia * mitogen-activated protein kinases (MAPK) Subject RIV: ED - Physiology Impact factor: 1.763, year: 2003

  19. Structural aspects of protein kinase ASK1 regulation

    Czech Academy of Sciences Publication Activity Database

    Obšil, Tomáš; Obšilová, Veronika

    2017-01-01

    Roč. 66, 1 Dec (2017), s. 31-36 ISSN 2212-4926 R&D Projects: GA ČR(CZ) GA16-02739S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:67985823 Keywords : ASK1 kinase * apoptosis * thioredoxin * 14-3-3 protein Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology

  20. Serum creatine kinase isoenzymes in children with osteogenesis imperfecta.

    Science.gov (United States)

    D'Eufemia, P; Finocchiaro, R; Zambrano, A; Lodato, V; Celli, L; Finocchiaro, S; Persiani, P; Turchetti, A; Celli, M

    2017-01-01

    This study evaluates serum creatine kinase isoenzyme activity in children with osteogenesis imperfecta to determine its usefulness as a biochemical marker during treatment with bisphosphonate. The changes of creatine kinase (CK) isoenzyme activity during and after discontinuation therapy were observed. These results could be useful in addressing over-treatment risk prevention. The brain isoenzyme of creatine kinase (CKbb) is highly expressed in mature osteoclasts during osteoclastogenesis, thus plays an important role in bone resorption. We previously identified high serum CKbb levels in 18 children with osteogenesis imperfect (OI) type 1 treated for 1 year with bisphosphonate (neridronate). In the present study, serum CK isoenzymes were evaluated in the same children with continuous versus discontinued neridronate treatment over a further 2-year follow-up period. This study included 18 children with OI type 1, 12 with continued (group A) and 6 with ceased (group B) neridronate treatment. Auxological data, serum biochemical markers of bone metabolism, bone mineral density z-score, and serum total CK and isoenzyme activities were determined in both groups. Serum CKbb was progressively and significantly increased in group A (p < 0.004) but rapidly decreased to undetectable levels in group B. In both groups, the cardiac muscle creatine kinase isoenzyme (CKmb) showed a marked decrease, while serum C-terminal telopeptide (CTx) levels were almost unchanged. This study provides evidence of the cumulative effect of neridronate administration in increasing serum CKbb levels and the reversible effect after its discontinuation. This approach could be employed for verifying the usefulness of serum CKbb as a biochemical marker in patients receiving prolonged bisphosphonate treatment. Moreover, the decreased serum CKmb levels suggest a systemic effect of these drugs.

  1. Nuclear translocation of doublecortin-like protein kinase and phosphorylation of a transcription factor JDP2

    Energy Technology Data Exchange (ETDEWEB)

    Nagamine, Tadashi; Nomada, Shohgo; Onouchi, Takashi; Kameshita, Isamu; Sueyoshi, Noriyuki, E-mail: sueyoshi@ag.kagawa-u.ac.jp

    2014-03-28

    Highlights: • Doublecortin-like protein kinase (DCLK) is a microtubule-associated protein kinase. • In living cells, DCLK was cleaved into two functional fragments. • zDCLK(kinase) was translocated into the nucleus by osmotic stresses. • Jun dimerization protein 2 (JDP2) was identified as zDCLK(kinase)-binding protein. • JDP2 was efficiently phosphorylated by zDCLK(kinase) only when histone was present. - Abstract: Doublecortin-like protein kinase (DCLK) is a microtubule-associated protein kinase predominantly expressed in brain. In a previous paper, we reported that zebrafish DCLK2 (zDCLK) was cleaved into two functional fragments; the N-terminal zDCLK(DC + SP) with microtubule-binding activity and the C-terminal zDCLK(kinase) with a Ser/Thr protein kinase activity. In this study, we demonstrated that zDCLK(kinase) was widely distributed in the cytoplasm and translocated into the nucleus when the cells were treated under hyperosmotic conditions with NaCl or mannitol. By two-hybrid screening using the C-terminal domain of DCLK, Jun dimerization protein 2 (JDP2), a nuclear transcription factor, was identified as zDCLK(kinase)-binding protein. Furthermore, JDP2 served as an efficient substrate for zDCLK(kinase) only when histone was present. These results suggest that the kinase fragment of DCLK is translocated into the nucleus upon hyperosmotic stresses and that the kinase efficiently phosphorylates JDP2, a possible target in the nucleus, with the aid of histones.

  2. MAP Kinase Pathways: Molecular Roads to Primary Acral Lentiginous Melanoma

    Science.gov (United States)

    Hsieh, Ricardo; de Freitas, Luiz A. R.; Brandao, Miguel A. R.; Lourenço, Silvia V.; Sangueza, Martin; Nico, Marcello M. S.

    2015-01-01

    Abstract: The etiology and pathogenesis of lentiginous acral melanomas are poorly understood. Recent studies have postulated that DNA repair mechanisms and cell growth pathways are involved in the development of melanoma, particularly changes in the MAPK pathways (RAS, BRAF, MEK 1/2, and ERK 1/2). The aim of this study is to assess the status of the MAP kinase pathways in the pathogenesis of acral melanomas. The authors examined the components of the RAS–RAF–MEK–ERK cascades by immunohistochemistry in a series of 16 primary acral melanomas by tissue microarray. The expression of MAP kinase cascade proteins changed in most cases. The authors observed that 57.14% of cases were BRAF positive and that 61.53%, 71.42%, and 71.42% of cases were positive for MEK2, ERK1, and ERK2, respectively; RAS was not expressed in 92.31%, and all cases were negative for MEK1. The absence of RAS and positivity for MEK2, ERK1, and ERK2 were most seen in invasive cases with high thickness. These aspects of the MAPK pathway require further examination in acral melanomas between different populations. Nevertheless, the results highlight significant alterations in the MAP kinase cascades that are related to histological indicators of prognosis in primary acral melanomas. PMID:26588333

  3. Septin-associated protein kinases in the yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Jeremy THORNER

    2016-11-01

    Full Text Available Septins are a family of eukaryotic GTP-binding proteins that associate into linear rods, which, in turn, polymerize end-on-end into filaments and further assemble into other, more elaborate super-structures at discrete subcellular locations. Hence, septin-based ensembles are considered elements of the cytoskeleton. One function of these structures that has been well-documented in studies conducted in budding yeast Saccharomyces cerevisiae is to serve as a scaffold that recruits regulatory proteins, which dictate the spatial and temporal control of certain aspects of the cell division cycle. In particular, septin-associated protein kinases couple cell cycle progression with cellular morphogenesis. Thus, septin-containing structures serve as signaling platforms that integrate a multitude of signals and coordinate key downstream networks required for cell cycle passage. This review summarizes what we currently understand about how the action of septin-associated protein kinases and their substrates control information flow to drive the cell cycle into and out of mitosis, to regulate bud growth, and especially to direct timely and efficient execution of cytokinesis and cell abscission. Thus, septin structures represent a regulatory node at the intersection of many signaling pathways. In addition, and importantly, the activities of certain septin-associated protein kinases also regulate the state of organization of the septins themselves, creating a complex feedback loop.

  4. New perspectives for targeting RAF kinase in human cancer.

    Science.gov (United States)

    Karoulia, Zoi; Gavathiotis, Evripidis; Poulikakos, Poulikos I

    2017-11-01

    The discovery that a subset of human tumours is dependent on mutationally deregulated BRAF kinase intensified the development of RAF inhibitors to be used as potential therapeutics. The US Food and Drug Administration (FDA)-approved second-generation RAF inhibitors vemurafenib and dabrafenib have elicited remarkable responses and improved survival of patients with BRAF-V600E/K melanoma, but their effectiveness is limited by resistance. Beyond melanoma, current clinical RAF inhibitors show modest efficacy when used for colorectal and thyroid BRAF-V600E tumours or for tumours harbouring BRAF alterations other than the V600 mutation. Accumulated experimental and clinical evidence indicates that the complex biochemical mechanisms of RAF kinase signalling account both for the effectiveness of RAF inhibitors and for the various mechanisms of tumour resistance to them. Recently, a number of next-generation RAF inhibitors, with diverse structural and biochemical properties, have entered preclinical and clinical development. In this Review, we discuss the current understanding of RAF kinase regulation, mechanisms of inhibitor action and related clinical resistance to these drugs. The recent elucidation of critical structural and biochemical aspects of RAF inhibitor action, combined with the availability of a number of structurally diverse RAF inhibitors currently in preclinical and clinical development, will enable the design of more effective RAF inhibitors and RAF-inhibitor-based therapeutic strategies, tailored to different clinical contexts.

  5. Cdc7 kinase - a new target for drug development.

    Science.gov (United States)

    Swords, Ronan; Mahalingam, Devalingam; O'Dwyer, Michael; Santocanale, Corrado; Kelly, Kevin; Carew, Jennifer; Giles, Francis

    2010-01-01

    The cell division cycle 7 (Cdc7) is a serine threonine kinase that is of critical importance in the regulation of normal cell cycle progression. Cdc7 kinase is highly conserved during evolution and much has been learned about its biological roles in humans through the study of lower eukaryotes, particularly yeasts. Two important regulator proteins, Dbf4 and Drf1, bind to and modulate the kinase activity of human Cdc7 which phosphorylates several sites on Mcm2 (minichromosome maintenance protein 2), one of the six subunits of the replicative DNA helicase needed for duplication of the genome. Through regulation of both DNA synthesis and DNA damage response, both key functions in the survival of tumour cells, Cdc7 becomes an attractive target for pharmacological inhibition. There are much data available on the pre-clinical anti-cancer effects of Cdc7 depletion and although there are no available Cdc7 inhibitors in clinical trials as yet, several lead compounds are being optimised for this purpose. In this review, we will address the current status of Cdc7 as an important target for new drug development.

  6. Human acylphosphatase cannot replace phosphoglycerate kinase in Saccharomyces cerevisiae.

    Science.gov (United States)

    Van Hoek, P; Modesti, A; Ramponi, G; Kötter, P; van Dijken, J P; Pron, J T

    2001-10-01

    Human acylphosphatase (h-AP, EC 3.6.1.7) has been reported to catalyse the hydrolysis of the 1-phosphate group of 1,3-diphosphoglycerate. In vivo operation of this reaction in the yeast Saccharomyces cerevisiae would bypass phosphoglycerate kinase and thus reduce the ATP yield from glycolysis. To investigate whether h-AP can indeed replace the S. cerevisiae phosphoglycerate kinase, a multi-copy plasmid carrying the h-AP gene under control of the yeast TDH3 promoter was introduced into a pgk1 delta mutant of S. cerevisiae. A strain carrying the expression vector without the h-AP cassette was used as a reference. For both strains, steady-state carbon- and energy-limited chemostat cultures were obtained at a dilution rate of 0.10 h(-1) on a medium containing a mixture of glucose and ethanol (15% and 85% on a carbon basis, respectively). Although the h-AP strain exhibited a high acylphosphatase activity in cell extracts, switching to glucose as sole carbon and energy source resulted in a complete arrest of glucose consumption and growth. The lack of a functional glycolytic pathway was further evident from the absence of ethanol formation in the presence of excess glucose in the culture. As h-AP cannot replace yeast phosphoglycerate kinase in vivo, the enzyme is not a useful tool to modify the ATP yield of glycolysis in S. cerevisiae.

  7. Differential Selective Pressures Experienced by the Aurora Kinase Gene Family

    Directory of Open Access Journals (Sweden)

    Joni M. Seeling

    2017-12-01

    Full Text Available Aurora kinases (AKs are serine/threonine kinases that are essential for cell division. Humans have three AK genes: AKA, AKB, and AKC. AKA is required for centrosome assembly, centrosome separation, and bipolar spindle assembly, and its mutation leads to abnormal spindle morphology. AKB is required for the spindle checkpoint and proper cytokinesis, and mutations cause chromosome misalignment and cytokinesis failure. AKC is expressed in germ cells, and has a role in meiosis analogous to that of AKB in mitosis. Mutation of any of the three isoforms can lead to cancer. AK proteins possess divergent N- and C-termini and a conserved central catalytic domain. We examined the evolution of the AK gene family using an identity matrix and by building a phylogenetic tree. The data suggest that AKA is the vertebrate ancestral gene, and that AKB and AKC resulted from gene duplication in placental mammals. In a nonsynonymous/synonymous rate substitution analysis, we found that AKB experienced the strongest, and AKC the weakest, purifying selection. Both the N- and C-termini and regions within the kinase domain experienced differential selection among the AK isoforms. These differentially selected sequences may be important for species specificity and isoform specificity, and are therefore potential therapeutic targets.

  8. S -Nitrosylation inhibits the kinase activity of tomato phosphoinositide-dependent kinase 1 (PDK1)

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jian-Zhong; Duan, Jicheng; Ni, Min; Liu, Zhen; Qiu, Wen-Li; Whitham, Steven A.; Qian, Wei-Jun

    2017-09-29

    It is well known that the reactive oxygen species, nitric oxide (NO), can trigger cell death in plants, but the underlying molecular mechanisms are not well understood. Here, we provide evidence that NO may trigger cell death in tomato (Solanum lycopersicon) through inhibiting the phosphoinositide-dependent kinase 1 (PDK1) kinase activity via S-nitrosylation. Biotin-switch assays and LC-MS/MS analyses demonstrated that SlPDK1 was a target of S-nitrosylation modification, which primarily occurred on the cysteine residue at position 128 (Cys128). Accordingly, the kinase activity of SlPDK1 was inhibited by S-nitrosoglutathione (GSNO) both in vitro and in vivo in a concentration-dependent manner, indicating that SlPDK1 activity is regulated by S-nitrosylation. The inhibition of SlPDK1 kinase activity by GSNO was reversible in the presence of a reducing agent but synergistically enhanced by hydrogen peroxide (H2O2). Mutation of Cys128 to serine completely abolished SlPDK1 kinase activity, suggesting that S-nitrosylation of Cys128 is responsible for the inhibition of the kinase activity of SlPDK1. In sum, our results established a potential link between NO-triggered cell death and inhibition of the kinase activity of tomato PDK1, a conserved negative regulator of cell death in yeasts, mammals and plants. Nitric oxide (NO) potentiates the induction of hypersensitive cell death in soybean cells by reactive oxygen species (ROS) (1). However, the molecular mechanism of the NO-induced cell death remains an enigma. One potential mechanism is that the activity of proteins that control cell death may be altered by a post-translational modification, S-nitrosylation. S-nitrosylation is the addition of the NO moiety to thiol groups, including cysteine (Cys) residues in proteins, to form S-nitrosothiols (SNOs). S-nitrosylation is an enzyme-independent post-translational and labile modification that can function as an on/off switch of protein activity (2- 4). Thousands of diverse

  9. Organ- and cell-type specific delivery of kinase inhibitors: a novel approach in the development of targeted drugs.

    NARCIS (Netherlands)

    Temming, Kai; Fretz, Marjan M; Kok, Robbert J

    2008-01-01

    During the past years, we have explored the cellular delivery of kinase inhibitors. Kinase inhibitors have selectivity for specific kinases but they lack cellular selectivity. This is exemplified by recent reports on cardiotoxicity of kinase inhibitors used in cancer treatment. We postulate that

  10. Cloning of MASK, a novel member of mammalian germinal center kinase-III subfamily, with apoptosis-inducing properties

    DEFF Research Database (Denmark)

    Dan, Ippeita; Ong, Shao-En; Watanabe, Norinobu M

    2002-01-01

    We have cloned a novel human GCK family kinase that has been designated as MASK (Mst3 and SOK1-related kinase). MASK is widely expressed and encodes a protein of 416 amino acid residues, with an N-terminal kinase domain and a unique C-terminal region. Like other GCK-III subfamily kinases, MASK does...

  11. The DNA-dependent protein kinase: a multifunctional protein kinase with roles in DNA double strand break repair and mitosis

    Science.gov (United States)

    Jette, Nicholas; Lees-Miller, Susan P.

    2015-01-01

    The DNA-dependent protein kinase (DNA-PK) is a serine/threonine protein kinase composed of a large catalytic subunit (DNA-PKcs) and the Ku70/80 heterodimer. Over the past two decades, significant progress has been made in elucidating the role of DNA-PK in non-homologous end joining (NHEJ), the major pathway for repair of ionizing radiation-induced DNA double strand breaks in human cells and recently, additional roles for DNA-PK have been reported. In this review, we will describe the biochemistry, structure and function of DNA-PK, its roles in DNA double strand break repair and its newly described roles in mitosis and other cellular processes. PMID:25550082

  12. Selective inhibition reveals cyclin-dependent kinase 2 as another kinase that phosphorylates the androgen receptor at serine 81

    Czech Academy of Sciences Publication Activity Database

    Jorda, Radek; Bučková, Zuzana; Řezníčková, Eva; Bouchal, J.; Kryštof, Vladimír

    2018-01-01

    Roč. 1865, č. 2 (2018), s. 354-363 ISSN 0167-4889 R&D Projects: GA MŠk(CZ) LO1204; GA MŠk(CZ) LO1304 Institutional support: RVO:61389030 Keywords : Androgen receptor * Cyclin-dependent kinase * Inhibitor * Phosphorylation * Serine 81 Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 4.521, year: 2016

  13. Methanol-dependent production of dihydroxyacetone and glycerol by mutants of the methylotrophic yeast Hansenula polymorpha blocked in dihydroxyacetone kinase and glycerol kinase

    NARCIS (Netherlands)

    Koning, W. de; Weusthuis, R.A.; Harder, W.; Dijkhuizen, L.

    Various factors controlling dihydroxyacetone (DHA) and glycerol production from methanol by resting cell suspensions of a mutant of Hansenula polymorpha, blocked in DHA kinase and glycerol kinase, were investigated. The presence of methanol (250 mM) and an additional substrate (0.5%, w/v) to

  14. Arabidopsis mitogen-activated protein kinase kinases MKK1 and MKK2 have overlapping functions in defense signaling mediated by MEKK1, MPK4, and MKS1

    DEFF Research Database (Denmark)

    Qiu, Jin-Long; Zhou, Lu; Yun, Byung-Wook

    2008-01-01

    by biochemical and molecular analyses implicating the kinases in jasmonate- and salicylate-dependent defense responses, mediated in part via the MPK4 substrate MKS1. In addition, transcriptome analyses delineate overlapping and specific effects of the kinases on global gene expression patterns demonstrating both...

  15. Phosphorylation of the regulatory beta-subunit of protein kinase CK2 by checkpoint kinase Chk1: identification of the in vitro CK2beta phosphorylation site

    DEFF Research Database (Denmark)

    Kristensen, Lars P; Larsen, Martin Røssel; Højrup, Peter

    2004-01-01

    The regulatory beta-subunit of protein kinase CK2 mediates the formation of the CK2 tetrameric form and it has functions independent of CK2 catalytic subunit through interaction with several intracellular proteins. Recently, we have shown that CK2beta associates with the human checkpoint kinase Chk...

  16. The Pim-1 protein kinase is an important regulator of MET receptor tyrosine kinase levels and signaling.

    Science.gov (United States)

    Cen, Bo; Xiong, Ying; Song, Jin H; Mahajan, Sandeep; DuPont, Rachel; McEachern, Kristen; DeAngelo, Daniel J; Cortes, Jorge E; Minden, Mark D; Ebens, Allen; Mims, Alice; LaRue, Amanda C; Kraft, Andrew S

    2014-07-01

    MET, the receptor for hepatocyte growth factor (HGF), plays an important role in signaling normal and tumor cell migration and invasion. Here, we describe a previously unrecognized mechanism that promotes MET expression in multiple tumor cell types. The levels of the Pim-1 protein kinase show a positive correlation with the levels of MET protein in human tumor cell lines and patient-derived tumor materials. Using small interfering RNA (siRNA), Pim knockout mice, small-molecule inhibitors, and overexpression of Pim-1, we confirmed this correlation and found that Pim-1 kinase activity regulates HGF-induced tumor cell migration, invasion, and cell scattering. The novel biochemical mechanism for these effects involves the ability of Pim-1 to control the translation of MET by regulating the phosphorylation of eukaryotic initiation factor 4B (eIF4B) on S406. This targeted phosphorylation is required for the binding of eIF4B to the eIF3 translation initiation complex. Importantly, Pim-1 action was validated by the evaluation of patient blood and bone marrow from a phase I clinical trial of a Pim kinase inhibitor, AZD1208. These results suggest that Pim inhibitors may have an important role in the treatment of patients where MET is driving tumor biology. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  17. Proteomics data on MAP Kinase Kinase 3 knock out bone marrow derived macrophages exposed to cigarette smoke extract

    Directory of Open Access Journals (Sweden)

    Roshni Srivastava

    2017-08-01

    Full Text Available This data article reports changes in the phosphoproteome and total proteome of cigarette smoke extract (CSE exposed WT and MAP Kinase Kinase 3 knock out (MKK3−/− bone marrow derived macrophages (BMDM. The dataset generated is helpful for understanding the mechanism of CSE induced inflammation and the role of MAP kinase signaling pathway. The cellular proteins were labeled with isobaric tags for relative and absolute quantitation (iTRAQ® reagents and analyzed by LC-MS/MS. The standard workflow module for iTRAQ® quantification within the Proteome Discoverer was utilized for the data analysis. Ingenuity Pathway Analysis (IPA software and Reactome was used to identify enriched canonical pathways and molecular networks (Mannam et al., 2016 [1]. All the associated mass spectrometry data has been deposited in the Yale Protein Expression Database (YPED with the web-link to the data: http://yped.med.yale.edu/repository/ViewSeriesMenu.do;jsessionid=6A5CB07543D8B529FAE8C3FCFE29471D?series_id=5044&series_name=MMK3+Deletion+in+MEFs

  18. Nucleic acid molecules encoding isopentenyl monophosphate kinase, and methods of use

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, Rodney B. (Pullman, WA); Lange, Bernd M. (Pullman, WA)

    2001-01-01

    A cDNA encoding isopentenyl monophosphate kinase (IPK) from peppermint (Mentha x piperita) has been isolated and sequenced, and the corresponding amino acid sequence has been determined. Accordingly, an isolated DNA sequence (SEQ ID NO:1) is provided which codes for the expression of isopentenyl monophosphate kinase (SEQ ID NO:2), from peppermint (Mentha x piperita). In other aspects, replicable recombinant cloning vehicles are provided which code for isopentenyl monophosphate kinase, or for a base sequence sufficiently complementary to at least a portion of isopentenyl monophosphate kinase DNA or RNA to enable hybridization therewith. In yet other aspects, modified host cells are provided that have been transformed, transfected, infected and/or injected with a recombinant cloning vehicle and/or DNA sequence encoding isopentenyl monophosphate kinase. Thus, systems and methods are provided for the recombinant expression of the aforementioned recombinant isopentenyl monophosphate kinase that may be used to facilitate its production, isolation and purification in significant amounts. Recombinant isopentenyl monophosphate kinase may be used to obtain expression or enhanced expression of isopentenyl monophosphate kinase in plants in order to enhance the production of isopentenyl monophosphate kinase, or isoprenoids derived therefrom, or may be otherwise employed for the regulation or expression of isopentenyl monophosphate kinase, or the production of its products.

  19. Evolutionary adaptations of plant AGC kinases: from light signaling to cell polarity regulation

    Directory of Open Access Journals (Sweden)

    Eike Hendrik Rademacher

    2012-11-01

    Full Text Available Signaling and trafficking over membranes involves a plethora of transmembrane proteins that control the flow of compounds or relay specific signaling events. Next to external cues internal stimuli can modify the activity or abundance of these proteins at the plasma membrane. One such regulatory mechanism is protein phosphorylation by membrane-associated kinases and phosphatases. The AGC kinase family is one of seven kinase families that are conserved in all eukaryotic genomes. In plants evolutionary adaptations introduced specific structural changes within the plant AGC kinases that most likely allow for sensing of external stimuli (i.e. light through controlled modification of kinase activity.Starting from the well-defined structural basis common to all AGC kinases we review the current knowledge on the structure-function relationship in plant AGC kinases. Nine of the 39 Arabidopsis AGC kinases have now been shown to be involved in the regulation of auxin transport. In particular, AGC kinase-mediated phosphorylation of the auxin transporters ABCB1 and ABCB19 has been shown to regulate their activity, while auxin transporters of the PIN family are located to different positions at the plasma membrane depending on their phosphorylation status, which is a result of counteracting AGC kinase and PP2A phosphatase activities. We therefore focus on regulation of AGC kinase activity in this context. Identified structural adaptations of the involved AGC kinases may provide new insight into AGC kinase functionality and demonstrate their position as central hubs in the cellular network controlling plant development and growth.

  20. Co-conserved features associated with cis regulation of ErbB tyrosine kinases.

    Directory of Open Access Journals (Sweden)

    Amar Mirza

    Full Text Available BACKGROUND: The epidermal growth factor receptor kinases, or ErbB kinases, belong to a large sub-group of receptor tyrosine kinases (RTKs, which share a conserved catalytic core. The catalytic core of ErbB kinases have functionally diverged from other RTKs in that they are activated by a unique allosteric mechanism that involves specific interactions between the kinase core and the flanking Juxtamembrane (JM and COOH-terminal tail (C-terminal tail. Although extensive studies on ErbB and related tyrosine kinases have provided important insights into the structural basis for ErbB kinase functional divergence, the sequence features that contribute to the unique regulation of ErbB kinases have not been systematically explored. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we use a Bayesian approach to identify the selective sequence constraints that most distinguish ErbB kinases from other receptor tyrosine kinases. We find that strong ErbB kinase-specific constraints are imposed on residues that tether the JM and C-terminal tail to key functional regions of the kinase core. A conserved RIxKExE motif in the JM-kinase linker region and a glutamine in the inter-lobe linker are identified as two of the most distinguishing features of the ErbB family. While the RIxKExE motif tethers the C-terminal tail to the N-lobe of the kinase domain, the glutamine tethers the C-terminal tail to hinge regions critical for inter-lobe movement. Comparison of the active and inactive crystal structures of ErbB kinases indicates that the identified residues are conformationally malleable and can potentially contribute to the cis regulation of the kinase core by the JM and C-terminal tail. ErbB3, and EGFR orthologs in sponges and parasitic worms, diverge from some of the canonical ErbB features, providing insights into sub-family and lineage-specific functional specialization. CONCLUSION/SIGNIFICANCE: Our analysis pinpoints key residues for mutational analysis, and

  1. High quality, small molecule-activity datasets for kinase research [version 3; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Rajan Sharma

    2016-10-01

    Full Text Available Kinases regulate cell growth, movement, and death. Deregulated kinase activity is a frequent cause of disease. The therapeutic potential of kinase inhibitors has led to large amounts of published structure activity relationship (SAR data. Bioactivity databases such as the Kinase Knowledgebase (KKB, WOMBAT, GOSTAR, and ChEMBL provide researchers with quantitative data characterizing the activity of compounds across many biological assays. The KKB, for example, contains over 1.8M kinase structure-activity data points reported in peer-reviewed journals and patents. In the spirit of fostering methods development and validation worldwide, we have extracted and have made available from the KKB 258K structure activity data points and 76K associated unique chemical structures across eight kinase targets. These data are freely available for download within this data note.

  2. Moonlighting kinases with guanylate cyclase activity can tune regulatory signal networks

    KAUST Repository

    Irving, Helen R.

    2012-02-01

    Guanylate cyclase (GC) catalyzes the formation of cGMP and it is only recently that such enzymes have been characterized in plants. One family of plant GCs contains the GC catalytic center encapsulated within the intracellular kinase domain of leucine rich repeat receptor like kinases such as the phytosulfokine and brassinosteroid receptors. In vitro studies show that both the kinase and GC domain have catalytic activity indicating that these kinase-GCs are examples of moonlighting proteins with dual catalytic function. The natural ligands for both receptors increase intracellular cGMP levels in isolated mesophyll protoplast assays suggesting that the GC activity is functionally relevant. cGMP production may have an autoregulatory role on receptor kinase activity and/or contribute to downstream cell expansion responses. We postulate that the receptors are members of a novel class of receptor kinases that contain functional moonlighting GC domains essential for complex signaling roles.

  3. Inhibitor repurposing reveals ALK, LTK, FGFR, RET and TRK kinases as the targets of AZD1480.

    Science.gov (United States)

    Gudernova, Iva; Balek, Lukas; Varecha, Miroslav; Kucerova, Jana Fialova; Kunova Bosakova, Michaela; Fafilek, Bohumil; Palusova, Veronika; Uldrijan, Stjepan; Trantirek, Lukas; Krejci, Pavel

    2017-12-12

    Many tyrosine kinase inhibitors (TKIs) have failed to reach human use due to insufficient activity in clinical trials. However, the failed TKIs may still benefit patients if their other kinase targets are identified by providing treatment focused on syndromes driven by these kinases. Here, we searched for novel targets of AZD1480, an inhibitor of JAK2 kinase that recently failed phase two cancer clinical trials due to a lack of activity. Twenty seven human receptor tyrosine kinases (RTKs) and 153 of their disease-associated mutants were in-cell profiled for activity in the presence of AZD1480 using a newly developed RTK plasmid library. We demonstrate that AZD1480 inhibits ALK, LTK, FGFR1-3, RET and TRKA-C kinases and uncover a physical basis of this specificity. The RTK activity profiling described here facilitates inhibitor repurposing by enabling rapid and efficient identification of novel TKI targets in cells.

  4. High quality, small molecule-activity datasets for kinase research [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Rajan Sharma

    2016-06-01

    Full Text Available Kinases regulate cell growth, movement, and death. Deregulated kinase activity is a frequent cause of disease. The therapeutic potential of kinase inhibitors has led to large amounts of published structure activity relationship (SAR data. Bioactivity databases such as the Kinase Knowledgebase (KKB, WOMBAT, GOSTAR, and ChEMBL provide researchers with quantitative data characterizing the activity of compounds across many biological assays. The KKB, for example, contains over 1.8M kinase structure-activity data points reported in peer-reviewed journals and patents. In the spirit of fostering methods development and validation worldwide, we have extracted and have made available from the KKB 258K structure activity data points and 76K associated unique chemical structures across eight kinase targets. These data are freely available for download within this data note.

  5. High quality, small molecule-activity datasets for kinase research [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Rajan Sharma

    2016-07-01

    Full Text Available Kinases regulate cell growth, movement, and death. Deregulated kinase activity is a frequent cause of disease. The therapeutic potential of kinase inhibitors has led to large amounts of published structure activity relationship (SAR data. Bioactivity databases such as the Kinase Knowledgebase (KKB, WOMBAT, GOSTAR, and ChEMBL provide researchers with quantitative data characterizing the activity of compounds across many biological assays. The KKB, for example, contains over 1.8M kinase structure-activity data points reported in peer-reviewed journals and patents. In the spirit of fostering methods development and validation worldwide, we have extracted and have made available from the KKB 258K structure activity data points and 76K associated unique chemical structures across eight kinase targets. These data are freely available for download within this data note.

  6. Research advances in kinase enzymes and inhibitors for cardiovascular disease treatment.

    Science.gov (United States)

    Shahin, Rand; Shaheen, Omar; El-Dahiyat, Faris; Habash, Maha; Saffour, Sana

    2017-11-01

    The targeting of protein kinases has great future potential for the design of new drugs against cardiovascular diseases (CVDs). Enormous efforts have been made toward achieving this aim. Unfortunately, kinase inhibitors designed to treat CVDs have suffered from numerous limitations such as poor selectivity, bad permeability and toxicity. So, where are we now in terms of discovering effective kinase targeting drugs to treat CVDs? Various drug design techniques have been approached for this purpose since the discovery of the inhibitory activity of Staurosporine against protein kinase C in 1986. This review aims to provide context for the status of several emerging classes of direct kinase modulators to treat CVDs and discuss challenges that are preventing scientists from finding new kinase drugs to treat heart disease.

  7. The anthraquinone emodin inhibits the non-exported FIKK kinase from Plasmodium falciparum.

    Science.gov (United States)

    Lin, Benjamin C; Harris, Darcy R; Kirkman, Lucy M D; Perez, Astrid M; Qian, Yiwen; Schermerhorn, Janse T; Hong, Min Y; Winston, Dennis S; Xu, Lingyin; Lieber, Alexander M; Hamilton, Matthew; Brandt, Gabriel S

    2017-12-01

    The FIKK family of kinases is unique to parasites of the Apicomplexan order, which includes all malaria parasites. Plasmodium falciparum, the most virulent form of human malaria, has a family of 19 FIKK kinases, most of which are exported into the host red blood cell during malaria infection. Here, we confirm that FIKK 8 is a non-exported member of the FIKK kinase family. Through expression and purification of the recombinant kinase domain, we establish that emodin is a relatively high-affinity (IC 50 =2μM) inhibitor of PfFk8. Closely related anthraquinones do not inhibit PfFk8, suggesting that the particular substitution pattern of emodin is critical to the inhibitory pharmacophore. This first report of a P. falciparum FIKK kinase inhibitor lays the groundwork for developing specific inhibitors of the various members of the FIKK kinase family in order to probe their physiological function. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. A switch in nucleotide affinity governs activation of the Src and Tec family kinases.

    Science.gov (United States)

    von Raußendorf, Freia; de Ruiter, Anita; Leonard, Thomas A

    2017-12-12

    The Tec kinases, closely related to Src family kinases, are essential for lymphocyte function in the adaptive immune system. Whilst the Src and Abl kinases are regulated by tail phosphorylation and N-terminal myristoylation respectively, the Tec kinases are notable for the absence of either regulatory element. We have found that the inactive conformations of the Tec kinase Itk and Src preferentially bind ADP over ATP, stabilising both proteins. We demonstrate that Itk adopts the same conformation as Src and that the autoinhibited conformation of Src is independent of its C-terminal tail. Allosteric activation of both Itk and Src depends critically on the disruption of a conserved hydrophobic stack that accompanies regulatory domain displacement. We show that a conformational switch permits the exchange of ADP for ATP, leading to efficient autophosphorylation and full activation. In summary, we propose a universal mechanism for the activation and autoinhibition of the Src and Tec kinases.

  9. Mer Tyrosine Kinase Regulates Disseminated Prostate Cancer Cellular Dormancy.

    Science.gov (United States)

    Cackowski, Frank C; Eber, Matthew R; Rhee, James; Decker, Ann M; Yumoto, Kenji; Berry, Janice E; Lee, Eunsohl; Shiozawa, Yusuke; Jung, Younghun; Aguirre-Ghiso, Julio A; Taichman, Russell S

    2017-04-01

    Many prostate cancer (PCa) recurrences are thought to be due to reactivation of disseminated tumor cells (DTCs). We previously found a role of the TAM family of receptor tyrosine kinases TYRO3, AXL, and MERTK in PCa dormancy regulation. However, the mechanism and contributions of the individual TAM receptors is largely unknown. Knockdown of MERTK, but not AXL or TYRO3 by shRNA in PCa cells induced a decreased ratio of P-Erk1/2 to P-p38, increased expression of p27, NR2F1, SOX2, and NANOG, induced higher levels of histone H3K9me3 and H3K27me3, and induced a G1/G0 arrest, all of which are associated with dormancy. Similar effects were also observed with siRNA. Most importantly, knockdown of MERTK in PCa cells increased metastasis free survival in an intra-cardiac injection mouse xenograft model. MERTK knockdown also failed to inhibit PCa growth in vitro and subcutaneous growth in vivo, which suggests that MERTK has specificity for dormancy regulation or requires a signal from the PCa microenvironment. The effects of MERTK on the cell cycle and histone methylation were reversed by p38 inhibitor SB203580, which indicates the importance of MAP kinases for MERTK dormancy regulation. Overall, this study shows that MERTK stimulates PCa dormancy escape through a MAP kinase dependent mechanism, also involving p27, pluripotency transcription factors, and histone methylation. J. Cell. Biochem. 118: 891-902, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  10. Presence of anaplastic lymphoma kinase in inflammatory breast cancer.

    Science.gov (United States)

    Robertson, Fredika M; Petricoin Iii, Emanuel F; Van Laere, Steven J; Bertucci, Francois; Chu, Khoi; Fernandez, Sandra V; Mu, Zhaomei; Alpaugh, Katherine; Pei, Jianming; Circo, Rita; Wulfkuhle, Julia; Ye, Zaiming; Boley, Kimberly M; Liu, Hui; Moraes, Ricardo; Zhang, Xuejun; Demaria, Ruggero; Barsky, Sanford H; Sun, Guoxian; Cristofanilli, Massimo

    2013-01-01

    Although Inflammatory Breast Cancer (IBC) is recognized as the most metastatic variant of locally advanced breast cancer, the molecular basis for the distinct clinical presentation and accelerated program of metastasis of IBC is unknown. Reverse phase protein arrays revealed activation of the receptor tyrosine kinase, anaplastic lymphoma kinase (ALK) and biochemically-linked downstream signaling molecules including JAK1/STAT3, AKT, mTor, PDK1, and AMPKβ in pre-clinical models of IBC. To evaluate the clinical relevance of ALK in IBC, analysis of 25 IBC patient tumors using the FDA approved diagnostic test for ALK genetic abnormalities was performed. These studies revealed that 20/25 (80%) had either increased ALK copy number, low level ALK gene amplification, or ALK gene expression, with a prevalence of ALK alterations in basal-like IBC. One of 25 patients was identified as having an EML4-ALK translocation. The generality of gains in ALK copy number in basal-like breast tumors with IBC characteristics was demonstrated by analysis of 479 breast tumors using the TGCA data-base and our newly developed 79 IBC-like gene signature. The small molecule dual tyrosine kinase cMET/ALK inhibitor, Crizotinib (PF-02341066/Xalkori®, Pfizer Inc), induced both cytotoxicity (IC50 = 0.89 μM) and apoptosis, with abrogation of pALK signaling in IBC tumor cells and in FC-IBC01 tumor xenograft model, a new IBC model derived from pleural effusion cells isolated from an ALK(+) IBC patient. Based on these studies, IBC patients are currently being evaluated for the presence of ALK genetic abnormalities and when eligible, are being enrolled into clinical trials evaluating ALK targeted therapeutics.

  11. Genomic organization of Bruton`s tyrosine kinase

    Energy Technology Data Exchange (ETDEWEB)

    Rohrer, J.; Conley, M.E. [Univ. of Tennessee, Memphis, TN (United States)

    1994-09-01

    Bruton`s tyrosine kinase (Btk), is a nonreceptor tyrosine kinase that has been identified as the defective gene in X-linked agammaglobulinemia (XLA). XLA patients have profound hypogammaglobulinemia and markedly reduced numbers of B cells while their T cell and phagocyte numbers remain normal. To determine the genomic organization of Btk, intron/exon borders were identified by sequencing cosmid DNA using cDNA primers. Nineteen exons spanning 37 kb of genomic DNA were identified. All the intron/exon splice junctions followed the GT/AG rule. The translational ATG start codon was in exon 2 which was 6 kb downstream of exon 1. Exon 19, 519 bp in length and 3.8 kb distal to exon 18, was the largest exon and included the 450 bp of the 3{prime} untranslated region. Exons 6 through 18 formed the largest cluster of exons with no intron being longer than 1550 bp. There was no apparent correlation between the exon boundaries of Btk and the functional domains of the protein or the exon boundaries of src, the nonreceptor protein tyrosine kinase prototype. The region 500 bp upstream of the presumed transcriptional start site was sequenced and found to have a G+C content of 52%. No TATA-type promoter elements in the -20 bp to -30 bp region were identified. However, at position -48 bp, a TGTGAA motif was found that bears some similarity to the TATA box. This sequence was preceded by a perfect inverted CCAAT box at position -90 bp. Three retinoic acid binding sites were also identified at positions -50 bp, -83 bp and -197 bp. Defining the genomic structure of Btk will permit us to identify regulatory elements in this gene and to identify mutations in genomic DNA of patients with XLA.

  12. Restricted Distribution of the Butyrate Kinase Pathway among Butyrate-Producing Bacteria from the Human Colon

    OpenAIRE

    Louis, Petra; Duncan, Sylvia H.; McCrae, Sheila I.; Millar, Jacqueline; Jackson, Michelle S.; Flint, Harry J.

    2004-01-01

    The final steps in butyrate synthesis by anaerobic bacteria can occur via butyrate kinase and phosphotransbutyrylase or via butyryl-coenzyme A (CoA):acetate CoA-transferase. Degenerate PCR and enzymatic assays were used to assess the presence of butyrate kinase among 38 anaerobic butyrate-producing bacterial isolates from human feces that represent three different clostridial clusters (IV, XIVa, and XVI). Only four strains were found to possess detectable butyrate kinase activity. These were ...

  13. NMR backbone assignments of the tyrosine kinase domain of human fibroblast growth factor receptor 1.

    Science.gov (United States)

    Vajpai, Navratna; Schott, Anne-Kathrin; Vogtherr, Martin; Breeze, Alexander L

    2014-04-01

    Members of the fibroblast growth factor receptor tyrosine kinase family (FGFR1-4) play an important role in many signalling cascades. Although tightly regulated, aberrant activity of these enzymes may lead to, or become features of, disease pathologies including cancer. FGFR isoforms have been the subject of drug discovery programmes, with a number of kinase-domain inhibitors in pre-clinical and clinical development. Here, we present the first (83% complete) backbone resonance assignments of apo-FGFR1 kinase.

  14. Systematic identification of the druggable interactions between human protein kinases and naturally occurring compounds in endometriosis.

    Science.gov (United States)

    Jiang, Lai; Tang, Chaoliang; Rao, Jie; Xue, Qing; Wu, Hao; Wu, Dabao; Zhang, Aijun; Chen, Ling; Shen, Zhen; Lei, Lei

    2017-12-01

    Diverse kinase signaling pathways have been involved in the pathogenesis of endometriosis (EM), which can be modulated either by directly targeting the hub kinases or by indirectly regulating marginal members in the pathways. Here, a systematic kinase-inhibitor interaction profile was created for 8 naturally occurring compounds against 20 human protein kinases. The compounds are all non-sterid that have been reported as pharmacologically active molecular entities potential for EM therapeutics, while the kinases were curated via gene ontology terms enriched from the gene co-citation network with EM. The resulting profile was analyzed at structural, energetic and dynamic levels to identify druggable kinase-compound interactions. The compounds Gossypol, Curcumin and EGCG showed a similar interaction profile across these kinases; they can bind tightly to the top-listed kinases in gene ontology, while the compounds Marrubiin, Apigenin and DIM were predicted to exhibit generally weak affinity for the 20 curated kinases. The JNK kinase, a MAPK family member, was identified as a putative candidate of druggable target for EM therapeutics; the inhibitory activity of eight naturally occurring compounds as well as a sophisticated kinase inhibitor SP600125 against the JNK was tested using enzymatic activity analysis. As might be expected, the Gossypol and EGCG were determined to have high inhibitory activity at namomolar level (IC 50 =55 and 94nM, respectively), which are comparable with or better than the positive control SP600125 (IC 50 =76nM), while other tested compounds exhibited weak inhibition (IC 50 >100nM) or bad potency (IC 50 =n.d.) against the kinase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Protein kinase A regulates AKAP250 (gravin) scaffold binding to the β2-adrenergic receptor

    OpenAIRE

    Tao, Jiangchuan; Wang, Hsien-yu; Malbon, Craig C.

    2003-01-01

    A-kinase-anchoring protein 250 (AKAP250; gravin) acts as a scaffold that binds protein kinase A (PKA), protein kinase C and protein phosphatases, associating reversibly with the β2-adrenergic receptor. The receptor-binding domain of the scaffold and the regulation of the receptor–scaffold association was revealed through mutagenesis and biochemical analyses. The AKAP domain found in other members of this superfamily is essential for the scaffold–receptor interactions. Gravin constructs lackin...

  16. Benzobisthiazoles Represent a Novel Scaffold for Kinase Inhibitors of CLK Family Members

    OpenAIRE

    Prak, K.; Kriston-Vizi, J.; Chan, A. W.; Luft, C.; Costa, J. R.; Pengo, N.; Ketteler, R.

    2016-01-01

    Protein kinases are essential regulators of most cellular processes and are involved in the etiology and progression of multiple diseases. The cdc2-like kinases (CLKs) have been linked to various neurodegenerative disorders, metabolic regulation, and virus infection, and the kinases have been recognized as potential drug targets. Here, we have developed a screening workflow for the identification of potent CLK2 inhibitors and identified compounds with a novel chemical scaffold structure, the ...

  17. The Drosophila rolled locus encodes a MAP kinase required in the sevenless signal transduction pathway.

    OpenAIRE

    Biggs, W H; Zavitz, K H; Dickson, B; van der Straten, A; Brunner, D; Hafen, E; Zipursky, S L

    1994-01-01

    Mitogen-activated protein (MAP) kinases have been proposed to play a critical role in receptor tyrosine kinase (RTK)-mediated signal transduction pathways. Although genetic and biochemical studies of RTK pathways in Caenorhabditis elegans, Drosophila melanogaster and mammals have revealed remarkable similarities, a genetic requirement for MAP kinases in RTK signaling has not been established. During retinal development in Drosophila, the sevenless (Sev) RTK is required for development of the ...

  18. Presenilin dependence of phospholipase C and protein kinase C signaling

    DEFF Research Database (Denmark)

    Dehvari, Nodi; Cedazo-Minguez, Angel; Isacsson, Ola

    2007-01-01

    -stimulated phospholipase C (PLC) activity which was gamma-secretase dependent. To further evaluate the dependence of PLC on PSs we measured PLC activity and the activation of variant protein kinase C (PKC) isoforms in mouse embryonic fibroblasts (MEFs) lacking either PS1, PS2, or both. PLC activity and PKCalpha...... and PKCgamma activations were significantly lower in PS1 and PS2 double knockout MEFs after PLC stimulation. Protein levels of PKCalpha and PKCgamma were lower in PS1 and PS2 double knockout MEFs. In contrast, PKCdelta levels were significantly elevated in PS1 and PS2 double knockout as well as in PS1 knockout...

  19. Protein Kinases in Mammary Gland Development and Carcinogenesis

    Science.gov (United States)

    1999-09-01

    of Krct expression was particularly high in the hippocampus and dentate mRNA expression revealed that although Krct is widely ex- gyms (Fig. 9). 2162...and dentate gyms . The novel serine/threonine kinase, Krct, was isolated initially as Te5U Te a cDA fagmnt n a egeerae oigoucletid PC sceen The 5’-UTR...1996; Vaughn et al., 1996b). These observa- BRCA2 expression by steroid hormones is of considerable tions, together with the finding that BR CA1 is a

  20. Tyrosine Kinase Inhibitor Treatment for Newly Diagnosed Chronic Myeloid Leukemia.

    Science.gov (United States)

    Radich, Jerald P; Mauro, Michael J

    2017-08-01

    Chronic myeloid leukemia (CML) is a myeloproliferative disorder that accounts for approximately 10% of new cases of leukemia. The introduction of tyrosine kinase inhibitors has led to a reduction in mortalities. Thus, the estimated prevalence of CML is increasing. The National Comprehensive Cancer Network and the European Leukemia Net guidelines incorporate frequent molecular monitoring of the fusion BCR-ABL transcript to ensure that patients reach and keep treatment milestones. Most patients with CML are diagnosed in the chronic phase, and approximately 10% to 30% of these patients will at some time in their course meet definition criteria of resistance to imatinib. Copyright © 2017 Elsevier Inc. All rights reserved.