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The Global ETD Search service is a free service for researchers
to find electronic theses and dissertations. This service is
provided by the
Networked Digital Library of Theses and Dissertations.
Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Showing 61 to 70 of 72 (0.264 seconds)Spelling suggestions: "subject:"sirna"" "subject:"mirna""
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Adding gears to the RNA machine: discovery and characterisation of new classes of small RNAs in eukaryotesRyan Taft Unknown Date (has links)
Genome sequencing has yielded unparalleled insights into fundamental biological processes and the genetics that guide them. In contrast to expectations that protein-coding genes would be the primary output of eukaryotic genomes, however, it is now clear that the vast majority of transcription is devoted to noncoding RNAs (ncRNAs). Although originally regarded as 'transcriptional noise', it is now clear that these transcripts are essential regulators of genetic activity. In this thesis I build upon the hypothesis that the genomes of eukaryotes encode a regulatory 'RNA machine' dominated by ncRNAs. In the Introduction (Chapter 1) I discuss how prior gene models may have inadvertently prevented a full understanding of ncRNAs, review the transcriptional landscape of eukaryotes, and examine the biogenesis and function of small regulatory RNAs. In support of a role for ncRNAs in complex metazoa, Chapter 2 presents data showing a positive correlation between the proportion of non-protein-coding DNA and biological complexity, suggesting that the evolutionary trajectory of intricate developmental phenotypes may have been facilitated by ncRNAs. In the following chapters two more 'gears' are added to the RNA machine. Chapter 3 details the discovery of snoRNA-derived RNAs - an evolutionarily ancient class of Argonaute-assocaited RNA whose biogenesis overlaps with microRNAs (miRNAs) and silencing RNAs (siRNAs). Likewise, Chapter 4 reports a new class of ~18 nt transcription initiation RNAs (tiRNAs) derived from regions proximal to transcription start sites. tiRNAs are enriched at GC-rich promoters and regions of active transcription, implicating them in transcriptional regulation. Chapter 5 presents evidence that tiRNAs are restricted to metazoa, and describes a model of RNA Polymerase II dependent tiRNA biogenesis. This thesis concludes with a general discussion of the implications of these findings, and the potential development of RNA therapeutics. Gathering evidence suggests that eukaryotic genomes are driven by a complex and interwoven network of RNA regulatory feedback loops. This thesis takes a small step towards developing a complete picture of this system.
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Adding gears to the RNA machine: discovery and characterisation of new classes of small RNAs in eukaryotesRyan Taft Unknown Date (has links)
Genome sequencing has yielded unparalleled insights into fundamental biological processes and the genetics that guide them. In contrast to expectations that protein-coding genes would be the primary output of eukaryotic genomes, however, it is now clear that the vast majority of transcription is devoted to noncoding RNAs (ncRNAs). Although originally regarded as 'transcriptional noise', it is now clear that these transcripts are essential regulators of genetic activity. In this thesis I build upon the hypothesis that the genomes of eukaryotes encode a regulatory 'RNA machine' dominated by ncRNAs. In the Introduction (Chapter 1) I discuss how prior gene models may have inadvertently prevented a full understanding of ncRNAs, review the transcriptional landscape of eukaryotes, and examine the biogenesis and function of small regulatory RNAs. In support of a role for ncRNAs in complex metazoa, Chapter 2 presents data showing a positive correlation between the proportion of non-protein-coding DNA and biological complexity, suggesting that the evolutionary trajectory of intricate developmental phenotypes may have been facilitated by ncRNAs. In the following chapters two more 'gears' are added to the RNA machine. Chapter 3 details the discovery of snoRNA-derived RNAs - an evolutionarily ancient class of Argonaute-assocaited RNA whose biogenesis overlaps with microRNAs (miRNAs) and silencing RNAs (siRNAs). Likewise, Chapter 4 reports a new class of ~18 nt transcription initiation RNAs (tiRNAs) derived from regions proximal to transcription start sites. tiRNAs are enriched at GC-rich promoters and regions of active transcription, implicating them in transcriptional regulation. Chapter 5 presents evidence that tiRNAs are restricted to metazoa, and describes a model of RNA Polymerase II dependent tiRNA biogenesis. This thesis concludes with a general discussion of the implications of these findings, and the potential development of RNA therapeutics. Gathering evidence suggests that eukaryotic genomes are driven by a complex and interwoven network of RNA regulatory feedback loops. This thesis takes a small step towards developing a complete picture of this system.
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Biochemical Mechanism of Gene Expression Silencing by piRNA-directed PIWI-Clade ArgonautesArif, Amena 10 August 2021 (has links)
Argonaute proteins are small DNA/RNA-guided endonucleases found in all domains of life. In animals, small RNAs of length 21–35 nucleotides direct the PIWI-clade of Argonautes to silence complementary target RNAs; these are called PIWI-interacting RNAs (piRNAs). During spermatogenesis in mice, piRNA-guided PIWI proteins, MIWI2, MILI, and MIWI, silence transposons, regulate expression of protein-coding genes and are necessary for fertility. A working endonuclease activity of MIWI and MILI is essential to complete spermatogenesis. Yet, both MIWI and MILI produce weak and slow target cleavage in vitro, thwarting biochemical examination of the silencing step. Here, we find that PIWI proteins require an auxiliary protein to efficiently cleave their targets, unlike any other known Argonaute. Gametocyte Specific Factor 1 (GTSF1) is a conserved zinc-finger protein essential for fertility and piRNA-directed silencing. We show GTSF1 accelerates the pre-steady-state rate of target cleavage by MIWI and MILI; this role of GTSF1 is also preserved in insects. A critical step in GTSF1 mechanism entails binding RNA. GTSF1 allowed detailed kinetic analyses of catalytic PIWIs: they require extensive 3′ complementarity between the guide and target to efficiently cleave them, but this base-pairing also limits turnover. Interestingly, within a species, different PIWI proteins have unique kinetic properties. In sum, our findings provide molecular mechanisms of GTSF1 function and target silencing by PIWIs as well as a useful method for future studies.
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Landkreisbroschüre: Landkreis Sächsische Schweiz-Osterzgebirge: Informationen für Bürger und Gäste08 August 2019 (has links)
Mit unserer Broschüre verbinden wir den Anspruch kompakt und anschaulich über den Landkreis, die regionale Wirtschaft, die besondere Landschaft und kulturelle Highlights zu informieren. Auf 96 Seiten können Sie einen Blick direkt in die Behörde Landratsamt werfen. Mit diesem Heft geben wir Ihnen einen Wegweiser an die Hand, der Sie bei Ihren behördlichen Anliegen zum richtigen Ansprechpartner führt. Außerdem ist uns wichtig zu zeigen, welche Dienstleistungen Sie bei uns in Anspruch nehmen können – von A wie Adoptionsvermittlung bis Z wie Zulassung von Kraftfahrzeugen.
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Katastrophenschutz-Broschüre des Landkreises Sächsische Schweiz-Osterzgebirge: in Kooperation mit der ostsächsischen Sparkasse Dresden und dem Kreisfeuerwehrverband Sächsische Schweiz-Osterzgebirge e.V.12 August 2019 (has links)
Extreme Wetterlagen und Großschadensereignisse stellen uns immer wieder vor Notfallsituationen. Es kann jeden treffen. Die Broschüre gibt Auskunft über die mögliche Prävention, Selbsthilfe, Verhalten im Notfall und über die Möglichkeiten der Feuerwehren, Rettungsdienste und Katastrophenschutzeinheiten.
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Regulation of gene expression by small non-coding RNA and CRISPR-dCas9Hoque, Mohammed Enamul 22 November 2022 (has links)
No description available.
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Radkarte Dresden Elbland29 April 2024 (has links)
Entdecken Sie unsere Region Dresden und das Elbland per Rad. Die in dieser Karte abgebildeten Touren
sind alphabetisch sortiert. Für weitere Informationen besuchen Sie gerne
unsere Website www.dresden-elbland.de/radtouren oder folgen Sie uns unter www.komoot.de/user/dresdenelbland.
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Evolution and Function of Compositional Patterns in Mammalian GenomesPrakash, Ashwin January 2011 (has links)
No description available.
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| 69 |
BIOGENESIS AND FUNCTIONAL APPLICATIONS OF PIWI INTERACTING RNAs (piRNAs)Balaratnam, Sumirtha 25 July 2018 (has links)
No description available.
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Gewerblich-industrielle Kulturlandschaften: Herausforderung für Kulturlandschaftsforschung und Regionalentwicklung - Untersuchungen am Beispiel des historischen Kalkgewerbes im Raum Pirna (Elbtalschiefergebirge) / Industrial-cultural landscapes: A challenge for culture landscape research and regional planning - A case study on the historical lime industry in the area of PirnaBieberstein, Christoph 16 April 2013 (has links) (PDF)
Im Zuge der Novellierung des Raumordnungsgesetzes (ROG) im Jahr 2008, wurde das Leitbild „Ressourcen bewahren – Kulturlandschaften gestalten“ neu hervorgehoben. Neben dem Schutzauftrag wurde dabei auch explizit ein aktiver Gestaltungs- und Entwicklungsauftrag als Schwerpunktthema in den Zielen der deutschen Raumordnung verankert. Am Beispiel des historischen Kalkgewerbes untersucht das Forschungsvorhaben, unter welchen Voraussetzungen Kulturlandschaftselemente eines historischen Gewerbezweiges überhaupt erfasst werden können und wie ihre Einbindung in Planwerke und Konzepte möglich wird. Die exemplarische Forschungsarbeit „vor Ort“ bildet, im Sinne eines Betrachtungsansatzes
aus der „Bottom-up“ Perspektive, die Basis der Arbeit. Auf diesem Wege soll der tatsächliche Handlungsrahmen der lokalen Akteure erschlossen sowie Hindernisse und Erfolgsfaktoren erkannt werden. Die praktische Kulturlandschaftsforschung zum historischen Kalkgewerbe ermöglicht es darüber hinaus den Forschungsstand zu diesem Gewerbezweig zu erweitern sowie seine Bedeutung für die Regionalgeschichte des Untersuchungsgebietes aufzuarbeiten. / During the reexamination of the law for regional organization (Raumordnungsgesetz) in 2008, the central theme “preserving resources – developing cultural landscapes“ was introduced. In addition to the need for preservation, the German spatial planning (Raumordnung) aims for an active process of creation and development. The thesis presented here uses a case study on the historical lime industry to address the question how and under which predispositions elements of an historical industry could be assessed and employed in the concepts for regional development. The exemplary fieldwork in the area of investigation allows for a “Bottom-up” perspective. Thus, the challenges that are faced by local operators could be documented and their actual options and requirements for pursuing a successful implementation of the project are evaluated. Furthermore, the applied cultural landscape research on the historical lime industry uncovered novel facts and insights into this industrial branch and its contributions to the history of the area of investigation.
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