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Cell senescence in aging, cell stress and chemoresistance
Andrašková, Tereza ; Vokřál, Ivan (advisor) ; Macháček, Miloslav (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Tereza Andrašková Supervisor: Prof. Dr. Alexandra K. Kiemer and PharmDr. Ivan Vokřál, PhD. Title of diploma thesis: Cell senescence in aging, cell stress, and chemoresistance The process of biological aging is connected with a loss of tissue function leading to the various pathologies, including cardiovascular diseases and cancer. Cellular senescence, the phenomenon characterized by permanent cell cycle arrest triggered by endogenous or exogenous stress plays a significant role in age-related metabolic diseases development. Senescent endothelial cells have been found in atherosclerotic plaque and due to the inflammation-inducing factors participate to its progression. Nevertheless, by triggering antiproliferative reaction, senescence may also have a potential as a cancer suppressor. The aim of this work was to establish assay determining senescence with different origins and subsequently, to analyse compounds with a potential to reduce H2O2-induced senescence as well as factors, which may be altered in the senescent phenotype. Senescence-associated β- galactosidase (SA-β-gal) assay in primary human endothelial cells revealed the senescence-inhibiting ability of statins and curcumin in contrast...
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Molecular mechanism of animal cells adaptation on hyperosmotic induced stress
Novotná, Jana ; Vávra, Jiří (advisor) ; Převorovský, Martin (referee)
Various types of cells animal tissues consist of need to adapt to intracellular as well as extracellular osmotic changes in order to maintain homeostasis. Hypertonicity (increased osmolarity) is one of the factors activating complex cellular reactions. In order to manage such stress, a cell needs to incorporate regulation pathways that can either regulate ion transporters through WNK kinases or activate gene expression of transporters of compatible osmolytes through the transcription factor TonEBP/NFAT5. Physiologically exposed to hypertonic conditions are cells in renal medulla, cartilage, inner ear tissues, in specialised neurons or buccal epithelium. This work includes basic and current knowledge about the adaption of cells to increased osmolarity of outer environment. Key words: Hyperosmolarity, osmotic stress, TonEBP/NFAT5, WNK kinases, NF-κB, HSP70
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Analysis of cell signaling mediated by the adapter protein Daxx
Švadlenka, Jan ; Anděra, Ladislav (advisor) ; Forstová, Jitka (referee) ; Stopka, Tomáš (referee)
2 Abstract Multifunctional adapter protein and histone chaperone Daxx has been described in nu- merous cellular processes, including the regulation of apoptotic and stress signalling, antiviral response and processes connected to chromatin (e. g. transcription). Its influ- ence on chromatin-related processes is mainly carried out by several associated en- zymes, such as DNA-methyltransferase-1, histone deacetylases and chromatin- remodelling ATPase ATRX. In the complex with ATRX Daxx functions as a chaperone of histone-3.3, maintaining the constitutive heterochromatin e. g. at centromeric and telomeric regions. The main aim of this Thesis was a better understanding of the Daxx cellular functions through identification and functional characterization of its novel interacting proteins. Using the yeast two-hybrid screen, several such new Daxx-interacting proteins were identified. These proteins were mainly nuclear, connected to the regulation of chroma- tin-related processes. More detailed analysis focused on the interaction of Daxx with chromatin-remodelling ATPase Brg1. This interaction was confirmed both in vitro and in the cells, where Daxx and Brg1 associated mainly in high molecular weight pro- tein complexes. These likely chromatin-remodelling complexes contain, in addition to Brg1, several...
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Analysis of cell signaling mediated by the adapter protein Daxx
Švadlenka, Jan
2 Abstract Multifunctional adapter protein and histone chaperone Daxx has been described in nu- merous cellular processes, including the regulation of apoptotic and stress signalling, antiviral response and processes connected to chromatin (e. g. transcription). Its influ- ence on chromatin-related processes is mainly carried out by several associated en- zymes, such as DNA-methyltransferase-1, histone deacetylases and chromatin- remodelling ATPase ATRX. In the complex with ATRX Daxx functions as a chaperone of histone-3.3, maintaining the constitutive heterochromatin e. g. at centromeric and telomeric regions. The main aim of this Thesis was a better understanding of the Daxx cellular functions through identification and functional characterization of its novel interacting proteins. Using the yeast two-hybrid screen, several such new Daxx-interacting proteins were identified. These proteins were mainly nuclear, connected to the regulation of chroma- tin-related processes. More detailed analysis focused on the interaction of Daxx with chromatin-remodelling ATPase Brg1. This interaction was confirmed both in vitro and in the cells, where Daxx and Brg1 associated mainly in high molecular weight pro- tein complexes. These likely chromatin-remodelling complexes contain, in addition to Brg1, several...
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Analysis of cell signaling mediated by the adapter protein Daxx
Švadlenka, Jan
2 Abstract Multifunctional adapter protein and histone chaperone Daxx has been described in nu- merous cellular processes, including the regulation of apoptotic and stress signalling, antiviral response and processes connected to chromatin (e. g. transcription). Its influ- ence on chromatin-related processes is mainly carried out by several associated en- zymes, such as DNA-methyltransferase-1, histone deacetylases and chromatin- remodelling ATPase ATRX. In the complex with ATRX Daxx functions as a chaperone of histone-3.3, maintaining the constitutive heterochromatin e. g. at centromeric and telomeric regions. The main aim of this Thesis was a better understanding of the Daxx cellular functions through identification and functional characterization of its novel interacting proteins. Using the yeast two-hybrid screen, several such new Daxx-interacting proteins were identified. These proteins were mainly nuclear, connected to the regulation of chroma- tin-related processes. More detailed analysis focused on the interaction of Daxx with chromatin-remodelling ATPase Brg1. This interaction was confirmed both in vitro and in the cells, where Daxx and Brg1 associated mainly in high molecular weight pro- tein complexes. These likely chromatin-remodelling complexes contain, in addition to Brg1, several...
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The role of SGK1 in heart
Havlíková, Nikola ; Horníková, Daniela (advisor) ; Mančíková, Andrea (referee)
Serum and glucocorticoid-regulated kinase 1 (SGK1) is an enzyme which is encoded by the sgk1 gene. This is a dimer. Generally, SGK1 belongs into the protein kinases, but its structure is somehow different from the other protein kinases, especially in the reaction center, which is related to its activity. SGK1 belongs to the subfamily of serine/threonine kinases. This kinase is activated by insulin or growth factors via phosphatidylinositol-3-kinase (PI3K) and mammalian rapamycin mTORC2. SGK1 plays an important role in inflammatory processes, the proliferation and apoptosis. In heart it helps to increase the abundance of proteins, which has affect on the morphology of ion channels and Na+ /K+ -ATPase. The sgk1 gene plays an important role in cellular stress response. This kinase activates potassium, sodium, chloride and calcium channels, which suggests about the involvement in the regulation of processes such as the cell survival, neuronal excitability and renal sodium excretion. Currently, the most discussed roles of SGK1 are in the heart, kidneys, brain, lungs and gastrointestinal tract. In recent years, it was found that SGK1 has different expression and regulation during the developmental stages and pathological conditions such as hypertension, diabetic neuropathy, ischemic trauma and...
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Analysis of cell signaling mediated by the adapter protein Daxx
Švadlenka, Jan ; Anděra, Ladislav (advisor) ; Forstová, Jitka (referee) ; Stopka, Tomáš (referee)
2 Abstract Multifunctional adapter protein and histone chaperone Daxx has been described in nu- merous cellular processes, including the regulation of apoptotic and stress signalling, antiviral response and processes connected to chromatin (e. g. transcription). Its influ- ence on chromatin-related processes is mainly carried out by several associated en- zymes, such as DNA-methyltransferase-1, histone deacetylases and chromatin- remodelling ATPase ATRX. In the complex with ATRX Daxx functions as a chaperone of histone-3.3, maintaining the constitutive heterochromatin e. g. at centromeric and telomeric regions. The main aim of this Thesis was a better understanding of the Daxx cellular functions through identification and functional characterization of its novel interacting proteins. Using the yeast two-hybrid screen, several such new Daxx-interacting proteins were identified. These proteins were mainly nuclear, connected to the regulation of chroma- tin-related processes. More detailed analysis focused on the interaction of Daxx with chromatin-remodelling ATPase Brg1. This interaction was confirmed both in vitro and in the cells, where Daxx and Brg1 associated mainly in high molecular weight pro- tein complexes. These likely chromatin-remodelling complexes contain, in addition to Brg1, several...
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Protein diversity in human stress granules
Kráčmarová, Jana ; Frydrýšková, Klára (advisor) ; Motlová, Lucia (referee)
During unfavourable conditions eukaryotic cells inhibit translation of certain mRNAs and preferably synthesize proteins that are involved in the stress response. The saved energy is used for repair of cellular damages. The untranslated mRNAs are accumulated in the form of ribonucleoprotein complexes. This accumulation results in the formation of the cytoplasmic stress granules. These granules are sites of structure remodeling and triage of the ribonucleoprotein complexes - they can be stored, degraded or sent back to the cytoplasm for translation reinitiation. The mRNA molecules carry their associated proteins, which include also proteins implicated in the cell signaling. Stress granules can thus indirectly regulate some processes, such as apoptosis, and play role in the survival of the cell. This thesis focuses on protein content of stress granules in human cell lines, briefly characterizes stress factors that induce their formation and discusses differences between the content of stress granules induced by different stress stimuli. An important part of this thesis is a table summarizing proteins found in the stress granules. The second part of this work is dedicated to the characterization of the proteins of the fragile X mental retardation protein family. It outlines the possible link between...
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