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Arts & Sciences Electronic Theses and Dissertations

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Full-Text Articles in Molecular Biology

The Role Of Mesenchymal Stromal Cells And Classical Dendritic Cells In The Maintenance And Regulation Of The Bone Marrow Niche, Jingzhu Zhang Aug 2018

The Role Of Mesenchymal Stromal Cells And Classical Dendritic Cells In The Maintenance And Regulation Of The Bone Marrow Niche, Jingzhu Zhang

Arts & Sciences Electronic Theses and Dissertations

The bone marrow niche is an important microenvironment for the regulation of normal and malignant hematopoiesis. The first discovered niche component is mesenchymal stromal cells, which are the major source for the production and secretion of multiple niche factors. Mesenchymal stromal cells are heterogeneous and various transgenes have been used to target non-identical but overlapping subpopulations. To further characterize the heterogeneity of mesenchymal stromal cells, we tested the targeting specificity of three tissue-specific Cre-recombinase transgenes. We show that in addition to osteoblasts, Ocn-Cre targets a majority of Cxcl12-abundant reticular (CAR) cells and arteriolar pericytes. Surprisingly, Dmp1-Cre also targets a subset ...


The Role Of Membrane Excitability In Insulin Regulation, Christopher Howard Emfinger Aug 2018

The Role Of Membrane Excitability In Insulin Regulation, Christopher Howard Emfinger

Arts & Sciences Electronic Theses and Dissertations

In mammals, ATP-sensitive K+ (KATP) channels are essential regulators of insulin secretion from pancreatic islet [beta]-cells, illustrated by the finding that gain-of-function mutations in KATP channels (KATP-GOF) cause neonatal diabetes mellitus (NDM). However, variability in symptom severity and effectiveness of treatment is seen in NDM, even for those with the same mutation and in the same family. Short-term treatment of mice expressing KATP-GOF mutations in [beta]-cells (KATP-GOF mice) with the KATP blocker glibenclamide during disease onset results in two outcomes: one subset becomes severely diabetic (non-remitters), whereas the other subset remains below the glucose levels at which significant ...


Characterization Of The Celf6 Rna Binding Protein: Effects On Mouse Vocal Behavior And Biochemical Function, Michael A. Rieger Aug 2018

Characterization Of The Celf6 Rna Binding Protein: Effects On Mouse Vocal Behavior And Biochemical Function, Michael A. Rieger

Arts & Sciences Electronic Theses and Dissertations

Behavior in higher eukaryotes is a complex process which integrates signals in the environment, the genetic makeup of the organism, and connectivity in the nervous system to produce extremely diverse adaptations to the phenomenon of existence. Unraveling the subcellular components that contribute to behavioral output is important for both understanding how behavior occurs in an unperturbed state, as well as understanding how behavior changes when the underlying systems that generate it are altered. Of the numerous molecular species that make up a cell, the regulation of messenger RNAs (mRNAs), the coding template of all proteins, is of key importance to ...


Development Of Lc-Ms For The Identification And Characterization Of Non-Adjacent Dna Photoproduct Formation In G-Quadruplex Forming Sequences, Claudia Posadas May 2018

Development Of Lc-Ms For The Identification And Characterization Of Non-Adjacent Dna Photoproduct Formation In G-Quadruplex Forming Sequences, Claudia Posadas

Arts & Sciences Electronic Theses and Dissertations

Ultraviolet light is well known to induce cyclobutane pyrimidine dimers (CPD) and pyrimidine (6–4) pyrimidone photoproducts in duplex DNA, which interfere with DNA replication and transcription. Recently, a new class of DNA photoproducts known as anti cyclobutanepyrimidine dimers have been discovered, which form in G-quadruplex forming sequences in solution. G-quadruplex structures have been proposed to form in human DNA telomeres and certain promoters in vivo but evidence for their existence has been lacking. Since anti-cyclobutante pyrimidine dimers have been shown to form in G-quadruplex forming sequences, their formation in irradiated human cells could be used to confirm the ...


Regulation Of Gene Expression By Rna Binding Proteins And Micrornas, Kyle Cottrell Dec 2017

Regulation Of Gene Expression By Rna Binding Proteins And Micrornas, Kyle Cottrell

Arts & Sciences Electronic Theses and Dissertations

Regulation of gene expression is essential to life. Post-transcriptional regulation of gene expression is a complex process with many inputs that lead to changes in localization, translation and stability of mRNAs. The translation and stability of many mRNAs is regulated by cis-elements, such as mRNA-structure or codon optimality; and by trans-acting factors such as RBPs and miRNAs. Here I report on the complex interactions between RBPs, miRNAs and characteristics of their target mRNAs in respect to effects on translation and RNA stability.

Using a reporter based approach we studied modulation of microRNA-mediated repression by various mRNA characteristics. We observed the ...


Specificity Determination By Paralogous Winged Helix-Turn-Helix Transcription Factors, Adam Joyce Aug 2017

Specificity Determination By Paralogous Winged Helix-Turn-Helix Transcription Factors, Adam Joyce

Arts & Sciences Electronic Theses and Dissertations

Transcription factors (TFs) localize to regulatory regions throughout the genome, where they exert physical or enzymatic control over the transcriptional machinery and regulate expression of target genes. Despite the substantial diversity of TFs found across all kingdoms of life, most belong to a relatively small number of structural families characterized by homologous DNA-binding domains (DBDs). In homologous DBDs, highly-conserved DNA-contacting residues define a characteristic ‘recognition potential’, or the limited sequence space containing high-affinity binding sites. Specificity-determining residues (SDRs) alter DNA binding preferences to further delineate this sequence space between homologous TFs, enabling functional divergence through the recognition of distinct genomic ...


Designing Epigenome Editing Tools To Understand The Functional Role Of Dna Methylation Changes In Cancer, James Mcdonald Aug 2017

Designing Epigenome Editing Tools To Understand The Functional Role Of Dna Methylation Changes In Cancer, James Mcdonald

Arts & Sciences Electronic Theses and Dissertations

DNA methylation is known to silence gene expression in the context of imprinting, X-chromosome inactivation, and retrotransposon silencing. However, the role of DNA methylation in silencing gene expression outside of these contexts is not fully understood. This is especially true in diseases such as cancer, where normal DNA methylation patterns are significantly altered. In breast cancer as well as nearly all cancer types, most of the genome loses DNA methylation while small regions of the genome gain methylation. DNA methylation generally correlates with decreased gene expression when present at a gene promoter. Therefore, these regions of hypo- and hyper-methylation may ...


Exploring Host-Virus Interactions In Caenorhabditis Nematodes, Kevin Chen Aug 2017

Exploring Host-Virus Interactions In Caenorhabditis Nematodes, Kevin Chen

Arts & Sciences Electronic Theses and Dissertations

Caenorhabditis elegans is a powerful model organism that has elucidated many biological questions in the fields of genetics, development, and neurobiology. In addition, C. elegans has been used in the past decade to investigate host-pathogen interactions with bacteria and fungi. The recent identification of nematode viruses that naturally infect C. elegans and Caenorhabditis briggsae provides a unique opportunity to define host-virus interactions in these model hosts.

This dissertation first explored the transcriptional response of C. elegans and C. briggsae to virus infection by RNA-seq. I identified a total of 320 differentially expressed genes (DEGs) in C. elegans following Orsay virus ...


Nuclear Export Factor 3 Regulates The Localization Of Small Nucleolar Rnas, Melissa Wanling Li Aug 2017

Nuclear Export Factor 3 Regulates The Localization Of Small Nucleolar Rnas, Melissa Wanling Li

Arts & Sciences Electronic Theses and Dissertations

Metabolic diseases, such as obesity and diabetes, are associated with excess levels of lipids, which can lead to organelle dysfunction, cell death and eventually organ dysfunction. This process, termed lipotoxicity, is still not completely understood. In a genetic screen used to identify genes critical for lipotoxicity, the Schaffer lab has identified small nucleolar RNAs (snoRNAs) within the ribosomal protein L13a (Rpl13a) locus that mediate the cellular response to lipotoxic and general metabolic stress. These snoRNAs are non-canonical in that they accumulate in the cytosol after metabolic stresses like lipotoxicity and oxidative stress, suggesting that cells have specific mechanisms for regulating ...


Mechanisms And Regulation Of Resection In Dna Damage Response, Sharad C. Paudyal Aug 2017

Mechanisms And Regulation Of Resection In Dna Damage Response, Sharad C. Paudyal

Arts & Sciences Electronic Theses and Dissertations

Deoxyribonucleic acid (DNA) encodes genetic information essential for cell survival and function. However, it is constantly under assault from endogenous and exogenous damaging agents that not only threaten our own survival but also affect the faithful transmission of genetic information to our offspring. Double-strand breaks (DSBs) are one of the most hazardous forms of DNA damage, which if unrepaired or improperly repaired could lead to plethora of systemic human diseases including cancer. To deal with this problem, cells have evolved with a mechanism called DNA damage response (DDR) to detect, signal, and repair the breaks by inducing multiple cellular events ...


The Role Of Rna Interference In The Control Of Leishmania Rna Virus 1 Infection, Erin Acino Brettmann May 2017

The Role Of Rna Interference In The Control Of Leishmania Rna Virus 1 Infection, Erin Acino Brettmann

Arts & Sciences Electronic Theses and Dissertations

The presence of Leishmania RNA virus 1 (LRV1) in parasites of the Leishmania (Viannia) subgenus increases the virulence of the parasite in mouse models of leishmaniasis and is correlated with treatment failure, relapse, and the development of mucocutaneous disease in humans. LRV1 is not shed or infectious; rather, the infection is persistent, and as yet it is unknown how the parasite controls virus levels. Many eukaryotic organisms use RNA interference (RNAi) to limit virus replication, and Leishmania (Viannia) parasites have an active RNAi pathway. To determine whether Leishmania are capable of using RNAi to control LRV1, we sequenced sRNAs from ...


The Rpl13a Snorna U33 Forms Novel Snornps During Lipotoxicity, Miquia Sherree Henderson May 2017

The Rpl13a Snorna U33 Forms Novel Snornps During Lipotoxicity, Miquia Sherree Henderson

Arts & Sciences Electronic Theses and Dissertations

Lipid overload contributes to the pathogenesis of diabetic complications, causing tissue damage and cell death in a number of organ systems. This process is termed lipotoxicity. Animal and cell culture studies have demonstrated that oxidative stress and endoplasmic reticulum stress are major pathways engaged in the lipotoxic response. However, the molecular mechanisms of lipotoxicity are not well understood. A genetic screen revealed that small nucleolar RNAs (snoRNAs) encoded in the introns of the Rpl13a locus are critical for cell death in response to lipotoxicity. Initial studies have suggested that the Rpl13a snoRNAs function in this pathway through non-canonical modes of ...


Structural, Biophysical, And Functional Studies Of Trem2 In Neurodegenerative Disease, Daniel L. Kober May 2017

Structural, Biophysical, And Functional Studies Of Trem2 In Neurodegenerative Disease, Daniel L. Kober

Arts & Sciences Electronic Theses and Dissertations

Alzheimer's disease (AD) and other neurodegenerative diseases present a large and growing challenge to global health. The immune system, particularly the innate immune system, is increasingly recognized as having a major role in these pathologies. The innate immune system is responsible to contain disease and promote healing. However, immune misregulation exacerbates disease. The innate immunomodulatory receptor Triggering receptor expressed on myeloid cells-2 (TREM2) is expressed on myeloid cells such as dendritic cells, macrophages, and in the brain, on microglia. TREM2 is a single-pass transmembrane receptor with an extracellular Ig domain that mediates ligand binding. This protein regulates inflammation in ...


Mechanisms Of G Protein Regulation By Rgs Proteins And Small Molecule Inhibitors, Stanley Michinobu Kanai May 2017

Mechanisms Of G Protein Regulation By Rgs Proteins And Small Molecule Inhibitors, Stanley Michinobu Kanai

Arts & Sciences Electronic Theses and Dissertations

G protein coupled receptors transduce diverse extracellular signals like hormones, neurotransmitters, and photons to specific cellular responses through heterotrimeric G proteins. G proteins activate numerous effectors and signal transduction pathways, and therefore the regulation of G proteins is crucial for faithful propagation of specific cellular and physiological responses. A better understanding of the mechanisms that regulate G proteins should provide new insight into signaling pathways that govern healthy and disease states, and also provide opportunities for discovery of novel therapeutic targets.Regulator of G protein signaling (RGS) proteins are crucial regulators of G proteins, for they control amplitude and duration ...


A Novel Ultrashort Pulsed Laser Method For Pathogen Inactivation, Shaw-Wei David Tsen May 2016

A Novel Ultrashort Pulsed Laser Method For Pathogen Inactivation, Shaw-Wei David Tsen

Arts & Sciences Electronic Theses and Dissertations

Emerging viral pathogens represent a constant and prominent threat to human health worldwide. There is a dire need to develop new pathogen inactivation techniques that can be used to safeguard the blood supply and to generate inactivated vaccines against these emerging viruses. Unfortunately, current techniques are inadequate because they introduce toxic/carcinogenic chemicals or alter the structure of the products, leading to loss of safety and efficacy. We have developed a novel, chemical-free ultrashort pulsed laser treatment system capable of inactivating a broad spectrum of both enveloped and non-enveloped viruses. We found that ultrashort pulsed laser treatment targets the vibrational ...


Application Of Genomic Technologies To Study Infertility, Nicholas Rui Yuan Ho May 2016

Application Of Genomic Technologies To Study Infertility, Nicholas Rui Yuan Ho

Arts & Sciences Electronic Theses and Dissertations

An estimated one in eight couples in the United States are diagnosed with infertility. There is a significant genetic contribution to infertility, with estimates of heritability ranging from 0.2 to 0.5. We know surprisingly little about the genetic causes, with only slightly more than a hundred genes known to cause human infertility. I have been translating recent advances in genomics to study infertility in a more efficient manner, in order to improve our knowledge of the genetic causes. By using high throughput genomics and proteomics datasets from other groups, I was able to feed that into a machine ...