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The Global ETD Search service is a free service for researchers
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Showing 1 to 6 of 6 (0.076 seconds)Spelling suggestions: "subject:"1protein aminases -- metabolism."" "subject:"1protein arginases -- metabolism.""
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Functional significance of phosphorylation of rat renal Na+,K+-ATPase by PKA and PKC /Cheng, Sam Xian Jun. January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.
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Control of cell cycle progression by the last MAPK Hog1Escoté Miró, Xavier 06 October 2005 (has links)
Exposure of yeast to increases in extracellular osmolarity activates the stress-activated Hog1 MAP kinase, which is essential for cell survival upon osmotic stress. Activation of the Hog1 MAPK results in cell growth arrest, suggesting a possible role of the MAP kinase in the control of the cell cycle. Our results have shown that Hog1 activation resulted in accumulation of cells in the G1/S and G2/M transitions. At G1, Hog1 regulates the cell cycle progression by a dual mechanism that involves downregulation of G1 cyclin expression and direct targeting of the CDK-inhibitor protein Sic1. The MAPK interacts with Sic1, and phosphorylates a single residue of Sic1, which, in combination with the downregulation of cyclin expression, results in Sic1 stabilization and inhibition of cell cycle progression. Consistently, sic1_ cells, or cells containing a SIC1 allele mutated in the Hog1 phosphorylation site, are unable to arrest at G1 phase after Hog1 activation, and become sensitive to osmostress. Together, our data indicate that Sic1 is the molecular target for Hog1 that is required to modulate cell cycle progression in response to stress at G1. On the other hand, activation of the Hog1 MAPK also results in an increase of cells in the G2 phase. Arrested cells displayed down regulation of the Clb2-Cdc28 kinase activity and consequently enlarged buds, defects in spindle formation and orientation. These effects were prevented by deletion of the SWE1 gene. Thus, swe1Ä cells failed to arrest at G2, which resulted in a premature entry into mitosis and mislocalization of nuclei. Consistently, swe1Ä cells were osmosensitive. Swe1 degradation was reduced in response to activation of Hog1. Swe1 accumulation is mediated by the activity of the complex Hsl1-Hsl7. Hog1 phosphorylates a single residue at the regulatory domain of Hsl1, which leads to the mislocalization of Hsl7 from the bud neck, and consequent Swe1 accumulation. In addition, Hog1 downregulates G2 cyclin expression, reinforcing the inhibition of cell cycle progression at G2/M. These results indicate that Hog1 imposes a delay in critical phases of cell cycle progression necessary for proper cellular adaptation to new extracellular conditions.
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The role of Ras and Kinase Suppressor of Ras 1 (KSR-1) in breast cancer in progression and metastasis /De Cristofano, Sabrina. January 2007 (has links)
The Ras signaling cascade is a vital component in the processes that mediate cell survival, growth, differentiation and transformation through activation of MAP kinase (mitogen-activated protein kinase). The recent discovery of a new scaffold of the Ras signaling pathway, Kinase Suppressor of Ras (KSR), is found to be a positive effector of Ras signaling which further contributes to proliferation and transformation in the ERK/MAPK pathway. This thesis describes the roles of Ras and Kinase Suppressor of Ras 1 (KSR-1) in regulating the expression of tumor promoting genes such as urokinase plasminogen activator (uPA) in the development and progression of breast cancer in vitro and in vivo. Ras and KSR increase the proliferative capacity and migration of MDAMB-231 human breast cancer cells in vitro. In contrast, Ras and KSR decrease the invasiveness of MDA-MB-231 human breast cancer cells in vitro. Furthermore, uPA gene expression levels do not correlate with uPA protein expression levels suggesting a possible mutation induced by KSR and/or Ras. In vivo studies reveal that Ras and KSR increase tumor volume in mice, as well as more advanced osteolytic bone metastases. Collectively, these results indicate that Ras and KSR play significant roles in breast cancer development and metastasis.
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The role of Ras and Kinase Suppressor of Ras 1 (KSR-1) in breast cancer in progression and metastasis /De Cristofano, Sabrina. January 2007 (has links)
No description available.
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Signal transduction mechanisms regulating the activation, adhesion and migration of human eosinophils and T-lymphocytes in allergic inflammation. / CUHK electronic theses & dissertations collectionJanuary 2003 (has links)
Ip Wai-Ki. / "July 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 261-290). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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Molecular Regulation of Interleukin-13 and Monocyte Chemoattractant Protein-1 Expression in Human Mast Cells by Interleukin-1betaLee, Steven A., Fitzgerald, S M., Huang, Shau K., Li, Chuanfu, Chi, David S., Milhorn, Denise M., Krishnaswamy, Guha 01 September 2004 (has links)
Mast cells play pivotal roles in immunoglobulin (Ig) E-mediated airway inflammation, expressing interleukin (IL)-13 and monocyte chemoattractant protein-1 (MCP-1), which in turn regulate IgE synthesis and/or inflammatory cell recruitment. The molecular effects of IL-1beta on cytokine expression by human mast cells (HMC) have not been studied well. In this report, we provide evidence that human umbilical cord blood-derived mast cells (CBDMC) and HMC-1 cells express the type 1 receptor for IL-1. We also demonstrate that IL-1beta and tumor necrosis factor-alpha are able to induce, individually or additively, dose-dependent expression of IL-13 and MCP-1 in these cells. The induction of IL-13 and MCP-1 gene expression by IL-1beta was accompanied by the activation of IL-1 receptor-associated kinase and translocation of the transcription factor, nuclear factor (NF) kappaB into the nucleus. Accordingly, Bay-11 7082, an inhibitor of NF-kappaB activation, inhibited IL-1beta-induced IL-13 and MCP-1 expression. IL-1beta also induced IL-13 promoter activity while enhancing the stability of IL-13 messenger RNA transcripts. Dexamethasone, a glucocorticoid, inhibited IL-1beta-induced nuclear translocation of NF-kappaB and also the secretion of IL-13 from mast cells. Our data suggest that IL-1beta can serve as a pivotal costimulus of inflammatory cytokine synthesis in human mast cells, and this may be partly mediated by IL-1 receptor-binding and subsequent signaling via nuclear translocation of NF-kappaB. Because IL-1beta is a ubiquitously expressed cytokine, these findings have important implications for non-IgE-mediated signaling in airway mast cells as well as for innate immunity and airway inflammatory responses, such as observed in extrinsic and intrinsic asthma.
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