Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 67 for “"DNA-methyltransferase"”.
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Kupplung der DNA-Methyltransferase M.SssI mit Triplehelix-bildenden Oligodesoxynucleotiden
DNA modifying enzymes, like DNA methyltransferases (DNA MTases) and restriction endonucleases (REases), could in principle be used to map or manipulate genomes. However, these enzymes are inappropriate for that purpose because of their generally short recognition sequences. An increase of their …
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Molecular Characterization of Mammalian De Novo DNA Methyltransferase Chromatin Recruitment
… diseases. The genomic localization of de novo DNA methyltransferases 3A (DNMT3A) and 3B (DNMT3B) is facilitated in part by chromatin "reader" domains to establish DNA methylation patterns genome-wide. Recent work has highlighted a role for the PWWP reader domain in directing recruitment of …
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Impact of the DNA methyltransferase inhibitor, 5-azacytidine, on chondrocytic phenotype
… research done in the Stewart lab suggests that DNA methylation is involved in the regulation of the chondrocytic phenotype. Therefore, the research presented in this dissertation is focused on characterizing the effects of DNA methylation on the chondrocytic phenotype, identifying the mechanisms …
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Functional consequences of cytosine methylation in mitochondrial DNA catalyzed by DNA methyltransferase 1
<p>Cytosine methylation of mitochondrial DNA (mtDNA) was first described several decades ago, but neither the mechanism generating this modification nor its functional significance was known. Because mitochondrial dysfunction is a hallmark characteristic of numerous human diseases, including …
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The role of the de novo DNA methyltransferase Dnmt3a in the nervous system
DNA methylation is an important mechanism of gene regulation. Evidence is mounting that epigenetic mechanisms including that of DNA methylation operate in the nervous system. Genetic disruption of the de novo DNA methyltransferase Dnmt3a in mice were used to elucidate the role of the enzyme in the …
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Super-specific DNA methylation by a DNA methyltransferase coupled with a triple helix-forming oligonucleotide
In this work, an engineered variant of the DNA cytosine-C5 methyltransferase (MTase) M.SssI has been conjugated with a triple helix-forming oligonucleotide (TFO) and the properties of the enzyme-TFO conjugate were evaluated using a variety of biochemical and biophysical methods. M.SssI is the only …
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Characterization of O6-Methylguanine DNA Methyltransferase and Base Excision DNA Repair Activity in Xiphophorous Fishes
Treatment of cells and/or DNA with direct acting alkylating agents (i.e. methyl-methane sulfonate; MMS, methyl nitrosourea; MNU, N-methyl-N-nitro-N nitrosoguanidine; MNNG) produces a wide spectrum of DNA adducts. The most frequent base adducts formed by alkylating agent exposure include those …
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Biological and Functional Consequences of Single Nucleotide Polymorphisms of the O6-Methylguanine-DNA-Methyltransferase Gene
Single nucleotide polymorphisms (SNPs) in DNA repair genes could alter the transcriptional levels, structure and function of DNA repair proteins and alter DNA repair proficiency. Consequently, these SNPs could significantly influence the level of genetic damage, which is an early critical factor in …
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Identifizierung und Charakterisierung von IPOD, einem neuen Interaktionspartner der DNA-Methyltransferase Dnmt2 aus Drosophila melanogaster
Die DNA-Methylierung spielt in der epigenetischen Vererbung und in der Entstehung von Krebs eine wichtige Rolle. Vor kurzem wurde gezeigt, dass die DNA-Methylierung in Drosophila Embryonen von Dnmt2 vermittelt wird. Dnmt2-Enzyme besitzen im Gegensatz zu anderen eukaryotischen DNA-Methyltransferasen …
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The role of the PWWP domain in the DNA methyltransferase 3A targeting to the genome
All cells in a mammalian body share the same DNA content but have a distinct appearance and function. This is achieved by activation and repression of genes by epigenetic mechanisms, which are crucial for stable differentiation of cells in a multi-cellular organism. DNA methylation, established by …
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Metabolism of lomustine in dogs and comparative cytotoxicity of lomustine and its major metabolites and O6-methylguanine-DNA methyltransferase expression in canine cells
… and its metabolites form similar levels of the DNA adducts N7 hydroxyethylguanine and O6 hydroxyethyldeoxyguanosine. These adducts may be used as molecular dosimeters of therapeutic response thus correlating to the similar cytotoxicity of these compounds. In terms of carbamylation, lomustine …
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Monosacchacharid-Konjugate von Inhibitoren der O6-Methylguanin-DNA Methyltransferase, der Poly-(ADP-ribose) Polymerase und des SWITCH Phänomens des HIV Hüllproteins gp120 : Synthese, biologische Aktivität und Struktur-Wirkungsbeziehungen
In dieser Arbeit wurden acetyl- oder benzoylgeschützte Bromoalkyl-Glucoside synthetisiert, die zur Einführung von Glycosylalkylresten in verschiedene Moleküle geeignet sind. So wurden O6-substituierten Purine zu MGMT-Inhibitor-Glucosiden, eine Hydroxyphenyl-benzimidazol-Grundstruktur zu …
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In Vitro Studies on the Methylation of DNA in Rat Brain and Liver Chromatin
<p>The properties of DNA methyltransferase in various age rats were investigated to better characterize the enzyme. When purified chromatin from 5-day-old rat brain or liver nuclei was incubated with S-adenosyl-L-[methyl-<sup>3</sup>H]-methionine, 5-[methyl-<sup>3</sup>H]methyl-cytosine was the …
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THE ROLE OF ACTIVE AND ACTIVE-SITE ALKYLATED HUMAN O6-METHYLGUANINE-DNA METHYTRANSFERASE (MGMT AND R-MGMT) IN DNA REPAIR AND BIOMONITORING
… and active-site alkylated human O6-methylguanine-DNA methyltransferase (MGMT and R-MGMT) in DNA repair and biomonitoring. The human DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT, Mr 22kd), which protects cells against the mutagenic effect of alkylating carcinogens, was found to be …
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Investigating Epigenetics as a Mechanism to Regulate Bacterial Heterologous Expression
Epigenetic DNA methylation in bacteria is involved in phage defense, and it can also affect gene transcription. Epigenetic methylation as part of restriction-modification systems is frequently considered a barrier in synthetic biology since it can prevent the introduction of heterologous genes to …
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The bioavailability of sulforaphane from broccoli products in men and its epigenetic activity
… the activities of histone deacetylase and DNA methyltransferase enzymes (5, 6). These effects were most pronounced at 10-15 µM SF, concentrations that are not typically obtained through dietary means. Furthermore, it has not been previously determined whether the inhibition of DNA …
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Analysen zur Funktion von Mehmet, einem neuen Interaktionspartner des Transkriptionsfaktors AP-2-alpha, sowie Charakterisierung von Mehmet in Drosophila melanogaster
… closely related and evolutionarily conserved DNA-binding proteins termed AP-2alpha, AP-2beta, AP-2gamma, AP-2delta and AP-2epsilon. They are characterized by an unique modular structure consisting of an aminoterminal transcriptional activation domain and a complex helix span helix motif for …
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