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Dissecting Interactions Across Gene Regulatory Layers In C. Elegans, Morgan Taylor

Biological Sciences Theses and Dissertations

The nematode Caenorhabditis elegans is a powerful tool for studying nervous system genetics. Though relatively simple compared to mammals, C. elegans boasts a remarkably well-conserved neuronal genome and proteome, and its utility in the characterization of neuronal genes has been well-established. However, gene expression is often controlled by complex interactions between multiple genes, and teasing apart the functions of individual genes within such networks remains a challenge. Dissecting these interaction networks is crucial in determining the multifaceted functions of important, conserved regulatory genes. Here we explore interactions between gene regulatory layers in the C. elegans nervous system, employing a synthetic …

Metoprolol Disrupts Sterol Biosynthesis Through Inhibition Of 7-Dehydrocholesterol Reductase (Dhcr7), Luke B. Allen

Theses & Dissertations

Cholesterol is essential for life. It is particularly important in the brain as it relies on de novo synthesis of cholesterol following the formation of the blood brain barrier (BBB). As such, disrupting sterol biosynthesis during neurodevelopment can have devastating outcomes. The most common post-lanosterol sterol biosynthesis disorder, Smith-Lemli-Opitz Syndrome, arises from a faulty DHCR7 enzyme. DHCR7 has also been shown to be inhibited by several psychotropic medications. Here we assess six beta-blockers and their effects on sterol biosynthesis in vitro. Two beta-blockers, metoprolol and nebivolol strongly inhibit DHCR7 in four separate in vitro models of both mouse and …

Novel Mechanisms Of Protein Kinase C Α Regulation And Function, Xinyue Li

Theses & Dissertations

Protein kinase Cα (PKCα) is a member of the PKC family of serine/threonine kinases, which have been implicated in regulation of many cellular processes, including cell proliferation, differentiation, survival, and transformation. A large body of evidence from the Black laboratory and others support an anti-proliferative function of PKCα in normal epithelial tissues, including the intestinal mucosa and endometrial epithelium. PKCα is also tumor suppressive in epithelial cancers, such as colorectal cancer (CRC) and endometrial cancer (EC). However, a major obstacle to harnessing the tumor suppressive functions of PKCα to benefit patients is the widespread loss of PKCα expression in tumors. …

Insights Into The Non-Osmoregulatory Function Of A Pollen-Specific Mechanosensitive Ion Channel, Kari Miller

Arts & Sciences Electronic Theses and Dissertations

Pollen, the male gametophyte of flowering plants, delivers the sperm cells to the ovule to carry out sexual reproduction. During this process, the pollen grain undergoes dramatic physical changes. Survival requires careful control of cell mechanics, particularly the balance between protoplast expansion and cell wall resistance. One control mechanism is the use of a mechanosensitive (MS) ion channel, MscS-Like (MSL)8. This pollen-specific protein was previously shown to be essential for pollen survival during hydration and was proposed to function as a tension-gated osmoregulator. However, direct proof of osmoregulation during initial hydration has not yet been found. In fact, studies of …

Functional Analysis Of Recurrent Non-Coding Variants In Human Melanoma, Paula Maria Godoy

Arts & Sciences Electronic Theses and Dissertations

Worldwide incidence rates of cutaneous melanoma are increasing, and while survival rates for early stages of melanoma are high, rates drop precipitously for metastatic melanomas or those that are unable to be targeted by currently available treatments. As melanomas have a propensity to quickly metastasize, understanding the contributions of melanoma initiation remains critical for early intervention. Onset of melanoma is characterized most by mutations that stimulate mitogen-activated protein kinase (MAPK) signaling, disrupt DNA damage checkpoints, and trigger mechanisms to bypass senescence through elongation of telomeres. Additionally, in zebrafish melanoma models, the earliest cluster of melanoma-initiating cells activate expression of a …

Next-Generation Sequencing Shows Increasing Temperatures Affect Stream Fungal Communities, Regan Hodgson

Electronic Theses and Dissertations

Under climate change predictions, surface air temperature is expected to continue to rise and will likely affect functioning of stream ecosystems and microbial communities. Aquatic hyphomycetes are key fungal decomposers of plant litter in headwater streams controlling carbon, energy, and nutrient flows to higher trophic levels. This project addressed the effects of temperature on stream fungal communities in two recently conducted experiments (microcosm and streamside channel studies) using Illumina sequencing. The objectives were to determine (1) if temperature affects community structure of stream fungi based on relative abundances of ITS2 rDNA sequences, (2) if the effects of temperature on aquatic …

Molecular Basis Of Viroid Rna-Templated Transcription, Shachinthaka D. Dissanayaka Mudiyanselage

Theses and Dissertations

Transcription is a fundamental process catalyzed by DNA-dependent RNA polymerases (DdRPs). Interestingly, some DdRPs can use both DNA and RNA as templates for transcription. This RNA-dependent RNA polymerase (RdRP) activity of DdRPs is used by RNA-based pathogens such as viroids and hepatitis delta virus for replication. In addition, RdRP activity of DdRPs widely occurs in various organisms to regulate gene transcription. Despite the importance of this intrinsic RdRP activity of DdRPs, associated factors and mechanisms are in their infancy stage. We employed potato spindle tuber viroid (PSTVd) as a model to study RNA-templated transcription. Here, we present evidence showing that …

Investigating The Involvement Of The Tick Vector In The Induction Of Alpha-Galactose Hypersensitivity (Alpha-Gal Syndrome, Red Meat Allergy) In The United States., Gary Crispell

Dissertations

Alpha-gal syndrome (AGS or sometimes called red meat allergy) is a result of the development of specific IgE antibodies to the oligosaccharide galactose-α-1,3-galactose (α-gal) after a person has had exposure to tick bites. This dissertation investigates four common tick species found in North America: the lone-star tick (Amblyomma americanum), the Gulf-Coast tick (Amblyomma maculatum), the American dog tick (Dermacentor variabilis), and the black-legged tick (Ixodes scapularis) for the presence of α-gal by utilizing a combination of immunoproteomic approaches and carbohydrate analysis techniques.

Anti-α-gal IgM antibodies (M86) were used in immunoblotting to detect …

Caribbean Reef-Building Coral-Symbiodiniaceae Network: Identifying Symbioses Critical For System Stability In A Changing Climate, Shaman Patel

All HCAS Student Capstones, Theses, and Dissertations

Increasing global ocean temperatures and frequency of marine heatwaves pose dire consequences for coral reefs. High temperatures often lead to disruptions in coral symbiosis resulting in coral bleaching, increasing the mortality of corals. However, corals can potentially avoid bleaching peril by associating with thermally tolerant symbionts. Here we provide a tool for understanding symbiosis network stability of Caribbean reef-building corals. We created a network of Caribbean hermatypic corals and their associated Symbiodiniaceae phylotypes. A bleaching model was applied to this network to test for resilience and robustness (R50) to thermal stress. It was also layered with trait data for coral …

Investigations Into Prg-2 And Its Involvement In Developing Gallus Gallus Retinal Neurons, Jeffrey Parham

Graduate Theses

I am interested in the development of the nervous system, especially since during development nerves grow and extend, but in adults, they do not regenerate if damaged. We are specifically interested in the molecules that guide nerves to the correct target during their development. Lysophosphatidic acid (LPA) is a bioactive molecule that has been shown to play a role in neural development. LPA, through repeated studies, has been shown to stop neurons from growing by causing a physical change in a neuron’s growth cone (a structure used for navigation and growth). Recently, a novel set of genes, called PRGs, have …

Sequencing And Functional Characterization Of A Latrodectus Geometricus Defensin, Lg-Defensin, Jacklyn Victoria Thompson

Electronic Theses and Dissertations

Defensins are small, cysteine-rich, immune related proteins described to be the most widespread family of invertebrate antimicrobial peptides. Presently, there is limited information regarding spider defensins. In this study, a new defensin peptide was described in Latrodectus geometricus, Lg-defensin. The full open reading frame was resolved using RACE and de novo assembly, followed by a bioinformatical analysis and phylogenetic alignment to determine conserved sequence patterns and structural similarities to other defensins. Next, the functionality of Lg-defensin was determined using in vitro RNA interference to assess what impact silencing had on the spider’s ability to control a gram-positive and gram-negative bacterial …

Exploring The Anticancer Mechanism Of Thienopyrazole Derivative Tpz-1 In Acute Myeloid Leukemia, Jessica Dyanne Hess

Open Access Theses & Dissertations

Anticancer drug discovery is a time and resource-consuming process for which exceedingly reliable and efficient modern approaches are needed. Phenotypic drug screenings can generate highly potent and innovative drug candidates; however, deconvolution of the drugâ??s target often presents significant barriers to drug development. To overcome this hurdle, we have originally combined in vitro and in silico analyses to uncover the molecular mechanism(s) driving the anticancer activity of the uniquely structured small molecule drug candidate, Tpz-1. Our study revealed that Tpz-1 is a multitargeted agent which induces the programmed death of HL-60 acute myeloid leukemia cells primarily through disruption of microtubule …

Dna Origami Scaffold Development For Digital Nucleic Acid Memory, Sarah Elizabeth Kobernat

Boise State University Theses and Dissertations

Recently, DNA nanotechnology has emerged as a promising and rapidly expanding method to utilize nucleic acids as a nanoscale building material. DNA origami is a major structural application of DNA nanotechnology, using DNA to construct two- and three-dimensional shapes. These structures have been employed for a variety of uses including DNA data storage. DNA is a promising material to address the impending shortage of silicon-based storage as data demands increase. There are many sequence-based methods of data storage, but digit Nucleic Acid Memory (dNAM) uses DNA origami as a breadboard and is read by super-resolution microscopy instead. dNAM uses DNA …

Structure, Function, And Immunogenic Applications Of Ab5-Type Adp-Ribosylating Bacterial Toxins, Elise Marie Overgaard

Boise State University Theses and Dissertations

Bacterial mono-ADP-ribosyltransferases (ARTs) catalyze the singular transfer of an ADP-ribose moiety from an NAD+ molecule onto a target molecule. ARTs contain an ancient and highly conserved tertiary structure and have a wide variety of intracellular targets and effects. Some, but not all, bacterial ARTs have an AB₅-type multimeric structure consisting of an enzymatically active subunit non-covalently situated atop of a non-toxic pentamer. The active, or A, subunit of AB₅-type toxins has a catalytic action that contributes to bacterial pathogenicity, and it is sometimes, but not always, an ART. ArtAB is an ART with AB₅-type …

The Role Of Vsmc Mir-33a Expression On Apoa-I Mediated Cholesterol Efflux And Macrophage-Like Cell Transdifferentiation, Ikechukwu Esobi

All Dissertations

Atherosclerosis is a condition caused by cholesterol accumulating in arterial intimal cells and is a disease that kills more people in the United States and globally than any other disease. Atherosclerosis is commonly recognized to arise from arterial intimal macrophage cholesterol accumulation, but cell lineage tracing technology has shown that a large majority of cholesterol-laden intimal cells found in atherosclerotic arteries are actually vascular smooth muscle cells that have switched phenotypes to a macrophage-like cell. This vascular smooth muscle cell to macrophage-like cell phenotypic switch is known as transdifferentiation and can be triggered by vascular smooth muscle cell cholesterol accumulation. …

A Novel Transmembrane Ligand Inhibits T Cell Receptor Activation, Yujie Ye

Doctoral Dissertations

T lymphocytes (T cells) play essential roles in the adaptive immune system. Each mature T cell expresses one type of functional T cell receptor (TCR). The TCR recognizes antigens bound to the major histocompatibility complex (MHC) in antigen presenting cells. The resulting stimulation signal crosses the transmembrane domain of TCR and initiates downstream signaling cascades. The human immune system relies on TCRs to recognize a variety of pathogens. Normally, TCR can distinguish the self-antigens from pathogenic antigens. However, dysfunction or aberrant expression of TCRs causes different inflammatory and autoimmune diseases, which afflict millions of people annually (Chapter I). Current treatments …

Comparative Analysis Of Conformational Transition Pathways In Homologous Proteins, Dylan Sebastien Ogden

Graduate Theses and Dissertations

Molecular dynamics (MD) simulations are routinely used to study the dynamics of proteins. However, conventional MD limited to the sampling of local conformational changes as the functionally important conformational transitions of proteins often extend beyond the timescales of the simulations employed, for example, membrane transport proteins. We have determined the combination of multiple MD based techniques that allows for a rigorous characterization of energetics and kinetics of large-scale conformational changes in membrane proteins. The methodology is based on biased, nonequilibrium collective variable based simulations including nonequilibrium pulling, string method with swarms of trajectories, bias-exchange umbrella sampling, and rate estimation techniques. …

The Antimicrobial Resistance Plasmid Mobilome Of Salmonella Enterica And Related Enteric Species And Factors That Influence The Transfer Efficiency., Suad Algarni

Graduate Theses and Dissertations

The dynamic distribution of antimicrobial resistance genes in Salmonella enterica is considered a public health risk. S. enterica is one of the most important etiological agents of foodborne illness and has a critical impact on global human health. In S. enterica and related species, mobile genetic elements (MGEs) serve as primary vehicles for the dissemination of antibiotic resistance genes in the bacterial evolution. This dissemination can be impacted by different selective pressures that leads to diverse antibiotic response phenotypes. This project focusses on the dynamics of antimicrobial resistance genes, particularly exploring the transfer efficiency of multidrug resistance plasmids in S. …

Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray

Graduate Theses and Dissertations

Life is remarkable in how resilient it can be. Many organism, classified as ex- tremophiles, can not only survive in extreme environments, but they can thrive in them. In the search for extraterrestrial life, the best candidates to harbor life exist with some kind of extreme condition. Europa, for example, is a favorite for the possibility of accommodating life as we know it within our solar system. Thought there is believed to be a liquid ocean under its icy surface, this habitat would be under immense pressures and high salinity. To best know where to look for extraterrestrial life, it …

Molecular Characterization Of Nitrogenase Regulation In Methanosarcina Acetivorans, Melissa Chanderban

Graduate Theses and Dissertations

Nitrogenase is the metalloenzyme only found in bacteria and archaea that is essential for biological nitrogen fixation (diazotrophy), but it can also serve as a catalyst in biofuel production. All diazotrophs contain a molybdenum (Mo) nitrogenase, while some species contain additional alternative nitrogenases where either vanadium (V) or iron (Fe) replace Mo in the active site cofactor. Nitrogen fixation by bacteria has been extensively studied. The limited investigation of nitrogen fixation in methanogenic archaea (methanogens) indicates production of nitrogenase is simpler than in bacteria and methanogen nitrogenase has different biochemical properties. Thus, methanogen nitrogenases provide a promising alternative for genetic …

Dpc29 Promotes Mitochondrial Translation Post-Initation In Saccharomyces Cerevisiae, Kyle Andrew Hubble

Graduate School of Biomedical Sciences Theses and Dissertations

Although the cytosolic and bacterial translation systems are well studied, much less is known about translation in mitochondria. In the yeast Saccharomyces cerevisiae, mitochondrial gene expression is predominately regulated by translational activators. These regulators are thought to promote translation by binding the elongated 5’-UTRs on their target mRNAs. Since mammalian mitochondrial mRNAs generally lack 5’-UTRs, they must regulate translation by other mechanisms. As expected, most yeast translational activators lack orthologues in mammals. Recently, a mitochondrial gene-specific translational activator, TACO1, was reported in mice and humans. To better define its role in mitochondrial translation I examined the yeast TACO1 orthologue, DPC29. …

Using Molecular Dynamics Simulations To Decipher Mechanistic Details Of Biomolecular Processes Of Biology And Biotechnology Oriented Applications, Adithya Polasa

Graduate Theses and Dissertations

Researchers in chemistry and biology often utilize computer simulations, in conjunction with experimental data, to model and predict the structures, energies, kinetics, processes, and functions of the systems that are their focus of study, ranging from single molecules to whole viruses. Here, we use molecular dynamics (MD) techniques to gain a deeper understanding of biomolecular processes in biology and biotechnology-oriented applications. Using a mixture of equilibrium and non-equilibrium MD simulations, this work describes the insertion process of YidC at the atomic level. In order to better comprehend the insertion process, several docking models of YidC-Pf3 in the lipid bilayer were …

Understanding SjöGren's Syndrome As A Systemic Autoimmune Disorder, Gaietchyne Chery

Legacy Theses & Dissertations (2009 - 2024)

Sjögren’s syndrome is an autoimmune condition characterized by a dysfunction in the lachrymal and salivary glands which results in dry eyes and dry mouth. Since its first description in 1892, the disease is one of the most common autoimmune diseases after lupus erythematosus and rheumatoid arthritis in the United States. Despite its high prevalence in the general population, Sjögren’s syndrome remains hard to diagnose due to the wide range of symptoms associated with the disease that is also shared by other conditions. Furthermore, the mechanisms behind the pathogenesis are not properly understood even though multiple factors have been proposed to …

Vircy-Seq : A Protocol For Characterizing Viral Activity, Tyler James Dion

Legacy Theses & Dissertations (2009 - 2024)

The main purpose of pharmaceutical production is to produce safe effective medicine for patient use. In an effort to ensure patient safety constant surveillance for viruses takes place. The detection of a viral nucleic acid in a pharmaceutical production setting results in investigations to assess its infectious potential. This is an intensive, expensive process that entails many tests such as the observation of hemadsorption, cytopathic effects (CPE), and more. These tests are typically specific and only capture certain viruses, as factors like CPE can only be observed in some viral species. A new investigational method that is effective on all …

Re-Engineering Cardio-Oncology Testing Using Biomimetic Heart Slice Cultures., Jessica Miller

Electronic Theses and Dissertations

28% of drug withdrawal from the market are due to unforeseen disruptions in cardiomyocyte contractility and electrophysiology. The most commonly used platforms for drug testing are in vivo animal models and in vitro cell culture models. While both have been of paramount importance for the discovery and detection of many cardiotoxicities and mechanisms of action, they lack the ability to model an intact human myocardium. This work aims to establish cardiac tissue slices, which are 300-micron thin tissue sections taken from the left ventricular myocardium, as an alternative platform for cardio-oncology studies, specifically cardiotoxicity testing. Additionally, this work aims to …

Ankyrin Dependent Mitochondrial Function And Bioenergetics In The Heart, Janani Subramaniam, Janani Subramaniam

Dissertations & Theses (Open Access)

ANK2 mutations in patients are associated with numerous arrhythmias, cardiomyopathies, and other heart defects. In the heart, AnkB, the protein encoded by ANK2, clusters relevant ion channels and cell adhesion molecules in several important domains; however, its role at Mitochondria Associated ER/SR Membranes (MAMs) has yet to be investigated. MAMs are crucial to mitochondrial function and metabolism and are signaling hubs implicated in various cardiac pathologies. Among several functions, these sites mediate the direct transfer of calcium from the ER/SR to the mitochondria to modulate ATP synthesis. Given that mitochondrial function and energy production are paramount to cardiovascular heath, …

T-Cell Antigen Receptors In Multiple Sclerosis, Lisa Lanée Keyes Jones

Biomedical Sciences Theses & Dissertations

Multiple Sclerosis (MS) is T-cell mediated autoimmune disease characterized by inflammation, demyelination, and degeneration of axons in the brain and spinal cord. A T cell-mediated immune response in MS is directed against myelin components and possibly other antigens in genetically susceptible individuals and is triggered by a viral infection. The T-cell antigen receptor (TCR) on T cells is responsible for antigen recognition and determines specificity. Our overall hypothesis is to determine whether clonally expanded T cells in patients with MS recognize viral or self-antigens and to determine whether molecular mimicry is involved in the development of the disease. To study …

Chromatin Regulation By Rb-Interacting Proteins In Cellular Immune Functions, Seung June Kim

Electronic Thesis and Dissertation Repository

The retinoblastoma protein (RB) is historically known for its function in cell cycle control. However, mice carrying targeted Rb1 mutations have revealed that RB serves various non-cell cycle control roles. Notably, RB acts as a scaffold that recruits chromatin regulatory proteins, condensin II and enhancer of zeste homolog 2 (EZH2). These complexes protect the genome integrity through maintaining proper chromosome condensation, long range contacts, and transcriptionally repressive histone modification. This thesis explores the mechanistic links that regulate such RB-condensin II complex or that are leveraged upon pharmacological inhibition of the RB-EZH2 complex. First, I identified potential phosphorylation sites in the …

The Effect Of Licogliflozin (Sglt1/2 Inhibitor) On Diabetes And Cardiac Complications, Alanoud Gharib Alblooshi

Theses

Diabetes mellitus (DM) is a chronic endocrine disease affecting millions of people worldwide. In spite of the advances made in the management of DM, poor glycemic control and diabetes complications are still very common. There is a continuous search for new and more effective drugs to treat DM. One of the drugs currently in clinical trials for the treatment of DM is licogliflozin (LIK066), a dual SGLT1/2 inhibitor, which can be used to treat obesity and diabetes. LIK066 inhibits glucose reabsorption in the kidney and small intestine, thereby reducing hyperglycemia. This study aims to investigate the efficacy of licogliflozin on …

Changes In Gene Expression From Long-Term Warming Revealed Using Metatranscriptome Mapping To Fac-Sorted Bacteria, Christopher A. Colvin

Masters Theses

Soil microbiomes play pivotal roles to the health of the environment by maintaining metabolic cycles. One question is how will climate change affect soil bacteria over time and what could the repercussions be. To answer these questions, the Harvard Forest Long-Term Warming Experiment was established to mimic predicted climate change by warming plots of land 5℃ above ambient conditions. In 2017, 14 soil core samples were collected from Barre Woods warming experiment to mark 15 years since the establishment of the soil warming in that location. These samples underwent traditional metatranscriptomics to generate an mRNA library as well as a …