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  • About
  • 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.
101

Genome-wide Characterization of RNA Expression and Processing

Zaghlool, Ammar January 2013 (has links)
The production of fully mature protein-coding transcripts is an intricate process that involves numerous regulation steps. The complexity of these steps provides the means for multilayered control of gene expression. Comprehensive understanding of gene expression regulation is essential for interpreting the role of gene expression programs in tissue specificity, development and disease. In this thesis, we aim to provide a better global view of the human transcriptome, focusing on its content, synthesis, processing and regulation using next-generation sequencing as a read-out. In Paper I, we show that sequencing of total RNA provides unique insights into RNA processing. Our results revealed that co-transcriptional splicing is a widespread mechanism in human and chimpanzee brain tissues. We also found a correlation between slowly removed introns and alternative splicing. In Paper II, we explore the benefits of exome capture approaches in combination with RNA-sequencing to detect transcripts expressed at low-levels. Based on our results, we demonstrate that this approach increases the sensitivity for detecting low level transcripts and leads to the identification of novel exons and splice isoforms. In Paper III, we highlight the advantages of performing RNA-sequencing on separate cytoplasmic and nuclear RNA fractions. In comparison with conventional poly(A) RNA, cytoplasmic RNA contained a significantly higher fraction of exonic sequence, providing increased sensitivity for splice junction detection and for improved de novo assembly. Conversely, the nuclear fraction showed an enrichment of unprocessed RNA compared to when sequencing total RNA, making it suitable for analysis of RNA processing dynamics. In Paper IV, we used exome sequencing to sequence the DNA of a patient with unexplained intellectual disability and identified a de novo mutation in BAZ1A, which encodes the chromatin-remodeling factor ACF1. Functional studies indicated that the mutation influences the expression of genes involved in extracellular matrix organization, synaptic function and vitamin D3 metabolism. The differential expression of CYP24A, SYNGAP1 and COL1A2 correlated with the patient’s clinical diagnosis. The findings presented in this thesis contribute towards an improved understanding of the human transcriptome in health and disease, and highlight the advantages of developing novel methods to obtain global and comprehensive views of the transcriptome.
102

Structural Analyses of a Human Valine Transfer RNA Gene and of a Transfer RNA Pseudogene Cluster

Lee, Mike Ming-Jen 12 1900 (has links)
Two different cloned human DNA segments encompassing transfer RNA gene and pseudogene clusters have been isolated from a human gene library harbored in bacteriophage lambda Charon 4-A. One clone (designated as λhVal7) encompassing a 20.5-kilobase (Kb) human DNA insert was found to contain a valine transfer RNA_AAC gene and several Alu-like elements by Southern blot hybridization analysis and DNA sequencing with the dideoxyribonucleotide chain-termination method in the bacteriophage M13mp19 vector. Another lambda clone (designated as λhLeu8) encompassing a 14.3-Kb segment of human DNA was found to contain a methionine elongator transfer RNA_CAT pseudogene and other as yet unidentified transfer RNA pseudogenes.
103

High resolution optical tweezers for single molecule studies of hierarchical folding in the pbuE riboswitch aptamer

Foster, Daniel. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on Jan. 27, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Physics, University of Alberta. Includes bibliographical references.
104

Improving the prediction of RNA secondary structure and automatic alignment of RNa sequences

Gardner, David Paul 02 July 2012 (has links)
The accurate prediction of an RNA secondary structure from its sequence will enhance the experimental design and interpretation for the increasing number of scientists that study RNA. While the computer programs that make these predictions have improved, additional improvements are necessary, in particular for larger RNAs. The first major section of this dissertation is concerned with improving the prediction accuracy of RNA secondary structures by generating new energetic parameters and evaluating a new RNA folding model. Statistical potentials for hairpin and internal loops produce significantly higher prediction accuracy when compared with nine other folding programs. While more improvements can be made to the energetic parameters used by secondary structure folding programs, I believe that a new approach is also necessary. I describe a RNA folding model that is predicated on a large body of computational and experimental work. This model includes energetics, contact distance, competition and a folding pathway. Each component of this folding model is evaluated and substantiated for its validity. The statistical potentials were created with comparative analysis. Comparative analysis requires the creation of highly accurate multiple RNA sequence alignments. The second major section of this dissertation is focused on my template-based sequence aligner, CRWAlign. Multiple sequence aligners generally run into problems when the pairwise sequence identity drops too low. By utilizing multiple dimensions of data to establish a profile for each position in a template alignment, CRWAlign is able to align new sequences with high accuracy even for pairs of sequence with low identity. / text
105

Functional characterization of the cellular protein p32 : a protein regulating adenovirus transcription and splicing through targeting of phosphorylation /

Öhrmalm, Christina, January 2006 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2006. / Härtill 4 uppsatser.
106

Influenza polymerase subunit compatibility between human H1 and H5 viruses

Li, Tin-wai, Olive, January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 139-160). Also available in print.
107

Influenza polymerase subunit compatibility between human H1 and H5 viruses /

Li, Tin-wai, Olive, January 2009 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 139-160). Also available online.
108

Exploring the roles of the RNA Polymerase II CTD in pre-MRNA metabolism /

Bird, Gregory A. January 2005 (has links)
Thesis (Ph.D. in Molecular Biology) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 130-152). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
109

Characterization of RNA-modifying enzymes and their roles in diseases

Warda, Ahmed 21 November 2017 (has links)
No description available.
110

Transcription initiation by the respiratory syncytial virus polymerase

Tremaglio, Chadene Zack 22 January 2016 (has links)
Respiratory syncytial virus (RSV) is the leading cause of respiratory illness in children worldwide. RSV has a negative sense RNA genome, which is the template for viral mRNA transcription and genome replication, and encodes a polymerase to carry out viral RNA synthesis. The promoters for RSV transcription and genome replication are found in a 44-nucleotide (nt), 3´-extragenic region called the leader (Le). Replication is initiated opposite the first nt of the Le, and transcription of the first gene begins at position +45, at a gene start (GS) sequence. However, transcription is also dependent on sequence within Le1-12. Interestingly, Le nucleotides 3-12 bear strong similarity to a GS signal. We hypothesized that this GS-like sequence is the recruitment site for transcribing polymerase. To test this hypothesis, we examined RNA synthesis events at the Le promoter. We identified a previously undescribed RNA initiation site at Le position +3 (Le+3) that was used frequently during RSV infection. Initiation at Le+3 led to the production of a small ~25 nt RNA. Le+3 initiation was shown to occur independently of replication initiation at +1, indicating it is a bona fide initiation site. Mutation of Le1-12 to increase similarity to a GS resulted in elongation of Le+3 RNA and a decrease in transcription initiation at the GS, demonstrating that the Le initiation sequence alters polymerase processivity and impacts downstream transcription events. Preliminary experiments to determine the function of the small RNA showed that it increased levels of viral RNA replication, suggesting it may be involved in influencing a switch from transcription to replication. These studies suggest a model for RSV transcription initiation, whereby the transcribing polymerase enters at the 3´–end of the genome, initiates RNA synthesis from Le+3 and generates a small RNA, and is then positioned to initiate transcription at the first GS. The small RNA that is generated may act as a feedback molecule to promote RNA replication. These findings provide a greater understanding of polymerase behavior at the promoter and may inform rational drug and vaccine design.

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