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Peroxiredoxin 6 And Inflammation In Alzheimer's Disease, Jared Ferrell-Penniman

Biological Sciences Theses and Dissertations

Alzheimer’s disease (AD) is known for its debilitating symptoms and poor prognosis. However, despite intense research into neurodegenerative diseases, there are few therapies targeted at the underlying mechanisms of the disease. Oxidative stress (OS) and inflammation are cellular phenomena thought to be key to the progression of the disease. Critically, peroxiredoxin 6 (Prx6), an antioxidant protein with multiple functions, has been identified from mammalian studies as a potential regulator of both OS and inflammation that may have a specific effect on AD. This project seeks to elucidate the role of Prx6 in AD as well as the underlying mechanisms. Drosophila …

Transcription Regulation Of Human Il1b Gene In Monocytes And Lymphoid Cd4 T Cells, Sree H. Pulugulla

Electronic Theses and Dissertations

Cytokines are key regulators of the inflammatory response and play an important role in facilitating intercellular communication between various immune cell types. Interleukin‑1β (IL‑1β) is a potent pro-inflammatory cytokine that is required for robust initiation of innate immune response and subsequent development of adaptive immunity. IL-1β is first synthesized as an inactive cytoplasmic, non‑glycosylated, precursor molecule (proIL‑1β) by monocytes and macrophages in response to invading pathogenic microbes. The activation of caspase‑1 by inflammasomes cleaves proIL-1β into mature biologically active IL-1β that is released from cells via a non-classical, endoplasmic reticulum‑independent secretory pathway directly from the cytoplasm via Gasdermin D membrane …

Hdac1 Is A Required Cofactor Of Cbfβ-Smmhc And A Therapeutic Target In Inversion 16 Acute Myeloid Leukemia, Lisa E. Richter

Theses & Dissertations

Acute myeloid leukemia (AML) is a neoplastic disease characterized by the uncontrolled proliferation and accumulation of immature myeloid cells. A common mutation in AML is the inversion of chromosome 16 [inv(16)], which generates a fusion between the genes for core binding factor beta (CBFB) and smooth muscle myosin heavy chain (MYH11), forming the oncogene CBFB-MYH11. The expressed protein, CBFβ-SMMHC, forms a heterodimer with the key hematopoietic transcription factor RUNX1. Although CBFβ-SMMHC was previously thought to dominantly repress RUNX1, recent work suggests that CBFβ-SMMHC functions together with RUNX1 to activate transcription of specific target genes.

Targeting the …

The Role Of Reactive Oxygen Species In Regulating Macrophage And Fibroblast Activation Within The Breast Cancer Tumor Microenvironment, Brandon J. Griess

Theses & Dissertations

The tumor microenvironment (TME) is a key determining factor in breast cancer, especially the more aggressive subtype triple negative breast cancer (TNBC). The activated fibroblasts and macrophages within the TME have many tumor promoting functions. Therefore, targeting their activation presents a novel therapeutic approach in TNBC. My work studied the role of reactive oxygen species (ROS) during fibroblast and macrophage activation in breast cancer.

My studies showed that expression of the secreted antioxidant enzyme, EcSOD, is silenced in breast cancer samples, in part, via increased promoter methylation. The re-expression of EcSOD inhibited c-Met activation in the TNBC cell line, MDA-MB231. …

Ecdysoneless, A Novel Regulator Of Ca2+ Homeostasis And Metabolism, Aniruddha Sarkar

Theses & Dissertations

The hallmarks of cancer include sustained proliferation and survival in the face of cellular stresses imposed by the oncogenic drive, as well as metabolic rewiring for tumor growth under adverse nutritional conditions. Adaptive alterations in key biochemical networks that underlie metabolic rewiring represent potential opportunities to develop new therapeutic strategies against cancer.

My thesis focuses on mammalian Ecdysoneless (ECD), a conserved homolog of the fly Ecdysoneless gene product, which engages fundamental cell biological processes of ER stress, Ca²⁺ signaling and metabolism to help sustain the oncogenic drive in tumor cells. Recent studies from our laboratory provide a clear evidence …

Functional Implications Of Nlrp1 Variants For Autoimmune Disease, Laura J. Westhoff

Undergraduate Honors Theses

NLRP1 is a protein-coding human gene that plays a crucial role in the NLRP1 inflammasome. Variants to the NLRP1 gene have been associated with autoimmune and autoinflammatory diseases. We examined the effects of polymorphisms at two SNPs on cytokine levels and NLRP1 gene expression in 50 human volunteers without diagnosed autoimmune disease. NLRP1 was genotyped at SNPs rs2670660 and rs12150220 and individuals who were homozygous at one or more SNP were selected for further analysis. Serum IL-18 and IL-1β levels were quantified using ELISA. NLRP1 gene expression was measured using real-time PCR. A strong linkage was found between genotypes of …

Brca1 & Ctdp1 Brct Domainomics In The Dna Damage Response, Kimiko L. Krieger

Theses & Dissertations

Genomic instability is one of the enabling characteristics of cancer. DNA damage response pathways are important for genomic integrity and cell cycle progression. Defects in DNA damage repair can often lead to cell cycle arrest, cell death, or tumorigenesis. The activation of the DNA damage response includes tightly regulated signaling cascades that involve kinase phosphorylation and modular domains that scaffold phosphorylated motifs to coordinate recruitment of DNA repair proteins. Modular domains are conserved tertiary structures of a protein that can fold, function, and evolve independently from an intact protein. One of the most common modular domains involved in DNA damage …

Delivery Of Small Molecule And Rna Using Synthetic Polymeric Micelles And Multifunctional Exosomes For The Treatment Of Type 1 Diabetes, Yang Peng

Theses & Dissertations

Type 1 diabetes is one of the most challenging chronic autoimmune diseases. The destruction and dysfunction of insulin-secreting β cells are the results of inflammatory infiltration and the synergistic effect of multiple immune cells. The aim of this dissertation is to develop novel and reliable therapeutic approaches to advance the treatment of T1D: including chemical modification of a broad-spectrum immunosuppressant, co-application of small molecule based immune intervention and siRNA based β cell preservative therapy, and administration of a PI3K-δ/γ dual inhibitor to specifically target immune cells, utilizing synthetic polymeric micelles or natural produced multi-functional exosomes derived from human bone marrow …

Cholesterol Biosynthesis In The Nervous System With An Emphasis On Desmosterolosis, Luke Allen

Theses & Dissertations

Cholesterol biosynthesis is integral to proper neurodevelopment due to the reliance on de novo synthesis of cholesterol in the brain. Disruptions in this process have devastating outcomes for human life characterized by several phenotypic manifestations concomitant with developmental delay. The cholesterol biosynthesis disorder desmosterolosis is an extremely rare disorder with a severe clinical phenotype, however, the models used to study this disease are not well characterized. In addition to genetic disruptions in cholesterol biosynthesis, pharmacological perturbation is an understudied side effect of many commonly prescribed drugs. Here we present a characterization of the sterol profile of the mouse model of …

Defining The Role Of Tyrosine Phosphorylation In The Regulation Of Connexin43 In Cardiac Diseases, Li Zheng

Theses & Dissertations

Connexins are integral membrane proteins that oligomerize to form gap junction channels. Ions and small molecules diffuse intercellularly through these channels, allowing individual cellular events to synchronize into the functional response of an entire organ. Gap junction channels composed of Connexin43 (Cx43) mediate electrical coupling and impulse propagation in the normal working myocardium. In the failing heart, Cx43 remodeling (decreased expression, altered phosphorylation state, loss at intercalated discs, and increased presence at lateral membranes) contributes to rhythm disturbances and contractile dysfunction. While there is considerable information regarding key interactions of Cx43 in the regulation of gap junction channels, unfortunately, the …

Activation And Regulation Of The Alkbh3-Ascc Alkylation Repair Pathway, Josh Brickner

Arts & Sciences Electronic Theses and Dissertations

DNA repair is essential to prevent the cytotoxic or mutagenic effects of various types of DNA lesions. These lesions are sensed by distinct pathways to recruit repair factors specific to type of damage. In particular, the ALKBH family of proteins recognizes and repairs specific alkylated lesions, including 1-methyladenine (m1A) and 3-methylcytosine (m3C). A major outstanding question in the field is how the AlkB homologue ALKBH3 and its associated protein partners are recruited to sites of alkylation damage and how this repair activity is regulated. Understanding the upstream signaling events that mediate recognition and repair of DNA alkylation damage is particularly …

Sideromycin Pathway Elucidation: Insights Into Salmycin Biosynthesis, Transport Paradigms, And Drug Release, Gerry Sann Macaraeg Rivera

Arts & Sciences Electronic Theses and Dissertations

Antibiotic resistance is an increasing threat in today’s society. In order to overcome resistant bacteria, it is necessary to discover new drugs with novel mechanisms of action. This work focuses on the sideromycin pathway, encompassing the biosynthetic production, mechanism of entry and hydrolysis-mediated drug release. Sideromycins are an interesting approach to combat the rise of antibiotic resistance since they provide a different avenue that overcomes problems that arise when entering the cell. The dissertation is separated into distinct sections dealing with the various areas of interest in the sideromycin pathway, particularly for the sideromycin, salmycin, produced by Streptomyces violaceus. The …

Investigating Biological Mechanisms Of Radiation Resistance In Advanced Stage Cervical Cancer, Fiona Ruiz

Arts & Sciences Electronic Theses and Dissertations

The current standard of care treatment for locally advanced cervical cancer is curative intent pelvic radiation with concurrently administered platinum chemotherapy (CRT). This treatment strategy is effective for many patients, but 33-50% of patients treated with CRT develop disease recurrence. Metastatic and recurrent cervical cancer is an incurable condition, and many of the currently available treatments are associated with significant morbidity and mortality. Identifying these patients upfront is a challenge that clinicians face when developing treatment strategies. Previous studies used to catalog the genomic and transcriptomic landscape of cervical cancer lacked high quality corresponding clinical follow up data for patients, …

Transcriptional Regulation Of Adipose Tissue Development By Pexrap And Med19, John Dean

Arts & Sciences Electronic Theses and Dissertations

Targeting adipose tissue function to decrease adiposity and improve insulin sensitivity could treat obesity and diabetes. How the nuclear receptor PPARγ regulates the development of two functionally distinct types of adipose tissue, brown and white fat (BAT and WAT), as well as the browning of white fat, remains unclear. Our previous studies suggest that PexRAP, a peroxisomal lipid synthetic enzyme, regulates PPARγ signaling and white adipogenesis.Here, we show that PexRAP is an inhibitor of brown adipocyte gene expression. PexRAP inactivation promoted adipocyte browning, increased energy expenditure, and decreased adiposity. Identification of PexRAP-interacting proteins suggests that PexRAP function extends beyond its …

A Noncanonical Function Of The Telomerase Rna Component In Human Embryonic Stem Cells, Kirsten Ann Brenner

Arts & Sciences Electronic Theses and Dissertations

Telomeres are stretches of TTAGGG nucleotide repeats located at the ends of linear chromosomes that shorten with progressive cell division and prevent genomic instability at the cost of limiting a cell’s capacity to proliferate. This limitation can be overcome by telomerase, a ribonucleoprotein complex that elongates telomeres via reverse-transcription of the template telomerase RNA component (TERC). Recent studies have reported potential functions of TERC outside of its role in telomere maintenance. These noncanonical functions of TERC are however poorly defined, and the molecular mechanisms and biological relevance behind such functions remain elusive. Here, we generated conditional TERC knock-out human embryonic …

Elucidating Enhancer Function In Epidermal Development And Filaggrin Loss-Of-Function Variants In African American Atopic Dermatitis, Mary Elizabeth Mathyer

Arts & Sciences Electronic Theses and Dissertations

The epidermis is the outermost tissue of the skin and provides the body’s first line of defense against external assaults. The epidermis is primarily composed of keratinocytes that terminally differentiate and rise apically toward the surface to form the semipermeable barrier of the skin. A hallmark of keratinocyte terminal differentiation is the expression of genes from the Epidermal Differentiation Complex (EDC) locus. Many of the EDC protein products contribute to the structural integrity of the skin barrier, evidenced by several gene knockouts such as loricrin, and even genetic variation within gene coding sequences, that modulate the integrity of the skin …

The Perplexing Paradox Of Clostridioides (Clostridium) Difficile Infection (Cdi) - Analysis Of Anti-Germinants As Part Of Cdi Prophylaxis, Christopher Yip

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides (Clostridium) difficile infections (CDI) have become the leading cause of nosocomial antibiotic-associated diarrhea worldwide. Under normal circumstances, bacteria found in the gastrointestinal tract provide a barrier against C. difficile colonization. Upon antibiotic therapy, the protective barrier is lost as the microbial community becomes depleted thus providing the opportunity for C. difficile to colonize the human gut. Exposure to taurocholate, a bile acid produced within the mammalian gastrointestinal tract, causes C. difficile spores to begin their transition, a process known as germination, from metabolically dormant structures to toxin-producing cells. As germination is required for the onset of CDI, anti-germination compounds …

Characterization Of The Nuclear Pore Complex In Red Alga, Cyanidioschyzon Merolae, Michelle Veronin

Health and Kinesiology Theses

Cyanidioschyzon merolae (C. merolae) is a primitive, unicellular species of red alga that is considered to be one of the simplest self-sustaining eukaryotes. The highly elementary nature of C. merolae makes it an excellent model organism for studying evolution as well as cell function and organelle communication. In our study, we hypothesize that C. merolae contains the minimal assembly of proteins to make up their Nuclear Pore Complexes (NPCs), and hence are the first ancestral NPCs. NPCs are essential for basic nuclear transport in the cell. They are embedded in the double membrane of the nucleus, the …

Characterization Of The Dimerization Domains On The Mannose-6-Phosphate/Insulin-Like Growth Factor Ii Receptor, Tyler Degener

Theses/Capstones/Creative Projects

The mannose-6-phosphate/insulin-like growth factor II (M6P/IGF2) receptor is a transmembrane protein known to sequester growth factors from the extracellular matrix. This behavior suggests a mechanism of tumor suppression. Structurally, the receptor’s extracellular region is segmented into 15 homologous repeats, which are divided further into 5 triplet domains, labelled 1-3, 4-6, 7-9, 10-12, and 13-15. What is notable about the triplets is their propensity to form dimers with triplets on a second M6P/IGF2 receptor. In fact, previous studies indicate that this protein functions optimally when dimerized. Thus, the purpose of this experiment is to characterize these domain interactions. Using a urea …

Recruitment Of Polycomb-Group Proteins At Giant In Drosophila Embryos, Elnaz Ghotbi Ravandi

Biological Sciences Theses and Dissertations

Polycomb Group (PcG) proteins are evolutionarily conserved epigenetic transcriptional regulators that maintain the transcriptional repression of silenced genes. PcG mediated silencing is divided into two phases: initiation and maintenance. During the initiation phase, PcG proteins initially recognize and bind to their target genes. Once PcG proteins are recruited to their target genes, they can maintain transcriptional repression through an unlimited number of cell cycles. Most studies on PcG proteins have been focused on the maintenance phase of PcG silencing, and the molecular mechanisms by which PcG proteins are initially recruited to their target genes remained unknown. Two models have been …

Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae, Rebecca E. Hardman

Graduate Theses and Dissertations

All organisms face a constant barrage of environmental stresses. Single-cell organisms such as Saccharomyces cerevisiae, or common Baker’s yeast, must rely solely on cellular responses in order to survive. This response must occur in a rapid and highly coordinated manner to quickly inhibit all unnecessary processes and shuttle all available resources to those necessary for survival. One method that cells utilize for rapid protein regulation is the use of post-translational modifications. Enzymes within the cell add or remove a variety of chemical modifications, thus altering the local chemical environment of a protein. This creates a conformational change in the protein …

Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich

Biomedical Sciences ETDs

Salivary gland adenoid cystic carcinoma (ACC) is an aggressive tumor with a tendency to infiltrate surrounding nerves and metastasize to distant sites. The standard treatment often fails to control local tumor recurrence and distant metastases and no approved targeted therapeutic options exist for these tumors. The goal of our studies was to reveal the molecular mechanisms driving ACC tumor development and novel drug targets to improve patient morbidity and mortality.

We first analyzed clinical and RNA-sequencing (RNA-seq) data for 68 formalin-fixed paraffin-embedded (FFPE) ACC tumor samples and described previously unappreciated molecular heterogeneity that predicts patient outcome. The poor outcome subgroup …

Natural Variation In Yeast Stress Signaling Reveals Multiple Paths To Similar Phenotypes, Amanda N. Scholes

Graduate Theses and Dissertations

Natural environments are dynamic, and organisms must sense and respond to changing conditions. One common way organisms deal with stressful environments is through gene expression changes, allowing for stress acclimation and resistance. Variation in stress sensing and signaling can potentially play a large role in how individuals with different genetic backgrounds are more or less resilient to stress. However, the mechanisms underlying how gene expression variation affects organismal fitness is often obscure.

To understand connections between gene expression variation and stress defense phenotypes, we have been exploiting natural variation in Saccharomyces cerevisiae stress responses using a unique phenotype called acquired …

Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr

Graduate Theses and Dissertations

Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …

Analyzing Multigene Stacking And Genome Editing Strategies In Rice, Bhuvan Pathak

Graduate Theses and Dissertations

Crop improvement through biotechnology is an integrated effort, incorporating multiple approaches like integration of genes, editing of native genes, and removal of selection marker genes. Before streamlining the protocols, the efficiency and feasibility of the individual approach and their components must be tested. This study evaluated following approaches: 1) stacking an array of genes into a single locus by site-specific integration via Cre-lox recombination in rice, 2) determining the efficiency of I-SceI and the CCR5-ZFN in the targeted excisions of gene fragments in rice and Arabidopsis, and 3) determining the efficiency of CRISPR/Cas9 in generating targeted mutations for genome editing …

Investigating Growth Performance And Intestinal Barrier Integrity In Heat-Stressed Modern Broilers And Their Ancestor Jungle Fowl, Travis Tabler

Graduate Theses and Dissertations

Heat stress (HS) has a negative effect on poultry production sustainability due to its adverse consequence on bird welfare, health, growth, and mortality. Although modern broilers have greater gut mass and higher energy use efficiency than unselected birds, they are more vulnerable to HS that induces “leaky gut syndrome,” or increased intestinal permeability. The aim of the current study was to determine the effect of HS on growth performance and gut barrier integrity in three modern broiler lines and their ancestor the Jungle Fowl. Four chicken populations including Giant Jungle Fowl (JF), Athens Canadian Random Bred (ACRB), 1995 Arkansas Random …

A Seascape Genetics Approach To Studying Genetic Differentiation In The Bull Kelp Nereocystis Luetkeana, Lily G. Gierke

Theses and Dissertations

The brown alga Nereocystis luetkeana is a foundation species found from Alaska to California. In the Salish Sea, N. luetkeana is declining, but little is known about its population structure. We explored N. luetkeana 1) allelic dissimilarity and richness using seven microsatellite markers, and 2) tested models of gene flow in the Salish Sea using a hydrodynamic transport model. Our results suggest that the N. luetkeana distribution is comprised of four genetic co-ancestry groups that are geographically coherent, apart from the separation of the Strait of Georgia/Puget Sound by the Strait of Juan de Fuca. Our model supported that environmental …

The Role Of Membrane Domains In Protein And Lipid Sorting During Endocytic Traffic, Blanca B. Diaz-Rohrer

Dissertations & Theses (Open Access)

The lipid and protein composition of the plasma membrane (PM) must be tightly controlled to maintain cellular functionality, despite constant, rapid endocytosis. Because de novo synthesis of proteins and lipids is energetically costly, the cell depends on active recycling to return endocytosed membrane components back to the PM. For most proteins, the mechanisms and pathways of their PM retention remain unknown. The work presented here shows that association with ordered membrane microdomains is fully sufficient for PM recycling and that abrogation of raft partitioning leads to their degradation in lysosomes. These findings support a model wherein ordered membrane domains mediate …

Investigation Of Phosphoserine Aminotransferase 1(Psat1) In Breast Cancer Progression., Stephanie Metcalf

Electronic Theses and Dissertations

This dissertation describes my research into the involvement of phosphoserine aminotransferase 1 (PSAT1) in breast cancer progression; specifically, in triple negative breast cancer (TNBC) metastasis and endocrine resistance in estrogen receptor positive breast cancer (ER+BC). Breast cancer is the most common tumor diagnosis among women. While the overall 5-year survival for breast cancer is reaching 90%, the 5-year survival for metastatic disease is only 22%. Metastasis and endocrine resistance combined can affect over 50% of patients. One of the proteins and pathways implicated in both metastasis and endocrine resistance in breast cancer is phosphoserine aminotransferase 1 (PSAT1) and the serine …

Single Molecule Fluorescence Studies Of Protein Structure And Dynamics Underlying The Chloroplast Signal Recognition Particle Targeting Pathway, Dustin R. Baucom

Graduate Theses and Dissertations

The work presented in this dissertation explores the structural dynamics in the chloroplast signal recognition particle pathway. Findings include cpSRP shows scanning functionality similar to that in the cytosolic SRP with the ribosome. The intrinsically disordered C-terminal tail of the Albino3 protein has some transient secondary structure. Upon binding to cpSRP43 in solution, separate secondary structure formation was identified in the C-terminal tail of Albino3. Finally, to increase efficiency of analyzing fluorescence time traces for this work, a modular software was produced.