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Chronic Circadian Misalignment Leads To Reduced Longevity And Largescale Changes In Gene Expression In Drosophila Melanogaster, Alex Christ Boomgarden

Master's Theses

As a result of earth's orientation toward the sun producing day and night, organisms have evolved an endogenous circadian timing system that is responsible for the 24-hour oscillation of most physiological and behavioral processes. This timing system is constantly synchronized to the external environment to adapt to and anticipate changes in light, temperature, food, and mate availability. In modern society, social and work constraints cause people to live schedules that are out of sync with their internal circadian clocks, producing a chronic circadian misalignment (CCM). While epidemiological studies in humans point to potentially damaging metabolic and cognitive consequences of CCM, …

Molecular Determinants Of Trim5Α Restriction And Recruitment Of Autophagic Effectors, Sabrina Imam

Dissertations

TRIM5α is an anti-viral restriction factor that inhibits the lifecycle of retroviruses. TRIM5α binds to and forms a hexameric lattice around the retroviral capsid, thereby initiating its antiviral activities, which include: (1) inhibition of viral infection; (2) inhibition of viral reverse transcription; (3) disassembly of the capsid; and (4), activation of innate signaling pathways. The formation of this assembly also activates the E3 ubiquitin ligase function of TRIM5α. Ubiquitin modification is associated with directing substrates to particular cellular pathways. We and others have shown that TRIM5α cytoplasmic bodies colocalize with proteins involved in the autophagy pathway, and we hypothesized that …

Role Of Micrornas In Impaired Gut Permeability Following Ethanol And Burn Injury, Niya Latrice Morris

Dissertations

Every year there are nearly 500,000 reported burn injuries in the United States; half of which occur under the influence of alcohol. Clinical studies have shown that burn patients who are intoxicated at the time of injury have a worse prognosis; including increased risk of multiple organ dysfunction syndrome (MODS) and sepsis. The etiology behind these pathological consequences of ethanol and burn injury remains to be elucidated. The Gut-lymph hypothesis of MODS theorizes that trauma (e.g. ethanol and burn injury) results in a redistribution of blood flow to protect more vital organs which leads to ischemia/hypoxia (diminished oxygen delivery) in …

Uncovering The Mechanisms Underlying The Immunogenicity Of Adenovirus Vaccine Vectors, Natalie Nidetz

Dissertations

Vaccination is historically the most effective tool for preventing infectious disease but current vaccine strategies fail to generate robust immunity to major infectious diseases such as HIV and malaria. Therefore, newer vaccine approaches are needed. Vaccines generated from viral, adenovirus based, vectors (AdVs) have proven highly immunogenic in multiple disease models. However, the clinical use of many AdVs is limited by the presence of pre-existing antibodies in human populations, which prevent expression of antigenic genes during immunization with AdVs based on common adenovirus (Ad) serotypes, such as HAdV-5C. Immunization with rare serotype based AdVs, such as HAdV-28D, are not affected …

A Discrete Loop In Serca N-Domain Plays A Role In Serca Headpiece Dynamics And Function, Olga N. Raguimova

Dissertations

The sarco/endoplasmic reticulum calcium ATPase (SERCA) is the major regulator of Ca2+ levels in the cell. Deficient calcium handling in the heart has been linked to heart failure, a leading cause of death in developed countries. As of today, targeting SERCA to enhance cardiac function has not been successful due to lack of details about SERCA structural dynamics during Ca2+ transport.

In my research, I utilized MD simulations and variety of physical assays to determine the role of Nβ5-β6 loop in regulation of SERCA structural dynamics during Ca2+ transport. Previous MD simulations by our lab predicted that the Nβ5-β6 loop …

Comparison Between The Structure-Function Relationship In The Wild Type Gαi1 Protein And Its Oncogenic Mutant, Jesse Lee Goossens

Dissertations

Many signal transduction pathways are regulated by guanine nucleotide-binding (G?) proteins, which function as molecular switches fluctuating between active and inactive conformations. Proper function depends on three flexible switch regions that are involved in the relatively slow hydrolysis of GTP. Deep sequencing studies have found mutations in the GNAS and GNAI1 genes involved in tumorigenesis, among which include a mutation corresponding to a highly conserved arginine residue in the switch II region. A mutation in GNAI1 encoding an R208Q change in G?i1 has been linked to intestinal cancers. We investigated the molecular basis of oncogenesis of this mutant by studying …

Characterizing Immune Response To Hiv-1 Infection In Bicd2-Knockout Cells, Omar Abdel-Rahim

Master's Theses

An important part of the HIV-1 infection cycle is the attachment of the intracellular viral core to the host microtubule network, facilitated by attachment of the viral capsid to cargo adaptor proteins. One such cargo adaptor is Bicaudal D Homolog Protein 2 (BICD2). BICD2 can attach to both the HIV-1 capsid and the dynein/dynactin complex and facilitate the trafficking of the viral core towards the host nucleus. Removal of BICD2 can disrupt this viral translocation, resulting in an elevated immune response that impairs productive HIV-1 infection. In my research, we investigated what viral particles are detected in the absence of …

Investigating Autophagy, Extracellular Vesicles, And Glycobiology, Benjamin Cook

Master's Theses

Autophagy is a cellular process of degradation which degrades cellular materials in acidic organelles called lysosomes. Impairment of lysosomal degradation can lead to lysosomal storage disorders such as Parkinson's Disease. In Parkinson's Disease neurotoxic α-synuclein can spread from cell-to-cell via extracellular vesicles. We investigated the changes in extra vesicular glycans upon perturbation of autophagy using a class of glycan binding molecules termed lectins.

We found that upon induction of autophagy causes EV glycans to increase while others remained consistent. Additionally, we found that specific glycans are increased more than others. Conversely, when lysosomal degradation was impaired, we observed a decrease …

Characterizing The Roles Of Staphylococcus Aureus Secreted Factors In Virulence And Modulation Of Innate Immune Cell Activity, Cameron Harvey

Master's Theses

Staphylococcus aureus is a prominent human pathogen that is responsible for a massive burden on healthcare. This thesis takes two approaches to characterize how S. aureus secreted factors subvert the innate immune response. First, characterization of the integral membrane protease 1984 showed that it regulates secretion of a putative lytic transglycosylase, IsaA, which is implicated in virulence. My results suggest IsaA and 1984 are capable of modulating immune responses that result in enhanced heart colonization in vivo. In addition, recent studies have uncovered TLR-independent pathways that induce inflammatory responses after S. aureus insult. Therefore, I hypothesized the bacterium secretes factors …

Understanding The Dynamics Of Protein Lipoylation In Staphylococcus Aureus, Sarah C. Flury

Master's Theses

Staphylococcus aureus is a commensal bacterium that also acts as an opportunistic pathogen. The pathogenicity of S. aureus has often been attributed to the wide range of virulence factors that the bacterium produces. While virulence factors do contribute a great deal, there is a growing field of research that aims to investigate the role of metabolism in bacterial virulence.

My project focuses on the necessity of a metabolic cofactor, lipoic acid. To ensure sufficient amounts of lipoic acid are available for enzyme activity, S. aureus has evolved two pathways to obtain the important nutrient. The lipoic acid salvage pathway is …

Induction Of Zika Virus-Specific Cd8+ T Cells By Means Of Dna Vaccine, Frank Gambino Jr.

Master's Theses

Zika virus (ZIKV) is a member of the virus family flaviviridae and is transmitted via Aedes aegypti mosquitos. Monoclonal antibodies against dengue virus have been found to cross-react with ZIKV but show no ability to neutralize it. Further studies have shown that Stat2-/- mice given plasma from dengue positive donors exhibit a heightened disease phenotype when challenged with ZIKV. Antibody dependent enhancement is theorized to cause such effect. The goal of this study was to design a plasmid which, when encoded, creates an antigen that will be used to stimulate exclusively CD8+ T cells. The gene sequence of NS3 was …

Cell Intrinsic Characteristics Of Cord Blood Naive Cd4 T Cells, Taylor Keller

Master's Theses

The neonatal immune system is functionally distinct from the adult immune system. Neonatal immune responses are less reactive than their adult counterparts, and as such, have an increased susceptibility to infection, resulting in increased duration and severity of disease. There is evidence that T-cells are partially responsible for the observed immunological differences between neonates and adults. Murine studies on neonatal immunity suggest that Th2 like responses predominate the neonatal immune system, an observation not found in the adult immune system. However, studies on human cord blood revealed that human neonates do not exhibit elevated Th2 like cytokines (with the exception …

Characterizing The Requirement Of The Cmi/Trr Compass-Like Complex During Drosophila Development, Timothy Nickels

Master's Theses

The MLR family of COMPASS-like complexes are histone methyltransferase complexes that are associated with the activation of gene enhancers. In D. melanogaster, Cara mitad (Cmi, also known as Lpt) and Trithorax related (Trr) are central subunits of a complex orthologous to mammalian Lysine methyltransferase 2 C and D (KMT2C and KMT2D, also known as MLL3 and MLL2/4) that catalyze H3K4 monomethylation. Previous studies have demonstrated that mutations in these genes are associated with cancer and developmental disorders, but the mechanisms by which these alterations contribute to disease states are unknown. The Cmi-containing COMPASS-like complex and orthologous vertebrate complexes have been …

Inhibition Of Mutant Egfr In Nsclc Promotes Endothelin-1-Mediated Nsclc Disease Progression, Stephen Ollosi

Master's Theses

Angiogenesis in NSCLC has been identified as important therapeutic target in combination with EGFR TKIs. However, only small incremental advancements have been made for the use of angiogenesis inhibitors in NSCLC and it remains elusive why the inhibition of VEGF-mediated neovascularization is not therapeutically efficacious. I present experimental evidence that a subpopulation of NSCLC cells with EGFR TKI-induced EMT contributes toward the attenuation of the response to EGFR TKI therapy. One of the hallmarks of cancer is heterogeneity and I have previously demonstrated that tumor heterogeneity within NSCLC cells lines harboring EGFR kinase domain mutations gives rise to divergent resistance …

Lidocaine Attenuates An Induced Inflammatory Response, Stephanie Zack

Master's Theses

Inflammation is common to the pathogenesis of a variety of diseases. Therapeutics which can regulate and reduce damaging inflammation are therefore valuable in the treatment of inflammation and inflammatory diseases.

One commonly used analgesic, recently identified as limiting inflammation, is lidocaine. Additionally, alternative, less toxic therapeutics like the snake venom peptides, Zep 3 and Zep 4, are thought to have anti-inflammatory effects. Yet a well-defined mechanism or cellular target for lidocaine or Zep peptides' anti-inflammatory effects has not been proposed.

We aimed to determine whether lidocaine and Zep peptides reduce the release of the proinflammatory cytokine, IL-1β, from activated human …

Cryptic Diversification Of Two Widespread Species In Madagascar, Lynika Sharlice Strozier

Master's Theses

Using phylogenetic and phylogeographic tools to uncover hidden diversity within the genus Newtonia in Madagascar

Madagascar is known for its rich biodiversity and high level of endemic species that are found nowhere else. Cryptic diversification, defined as genetically and evolutionarily distinct species that are hard to detect because they are morphologically indistinguishable from their closest relatives, has been hypothesized to occur in many groups on Madagascar. Currently it is unclear to what extent this phenomenon occurs in birds because only a few studies have been conducted. My study examined the phylogenetic and phylogeographic patterns within a songbird genus, Newtonia, that …

The Characterization Of Rna Content And Biogenesis Pathways Of Extracellular Vesicles That Have Been Implicated In The Pathogenesis Of Hiv-1 Associated Neurocognitive Disorders, Virginia Elizabeth Zwikelmaier

Master's Theses

Patients infected with HIV-1 adhering to Anti-Retroviral Therapy (ART) still suffer from a variety of neurocognitive, behavioral, and motor dysfunctions, collectively referred to has HIV-1 Associated Neurocognitive Disorders (HAND). Current research suggests the manifestations of HAND might in part be due to the dissemination of toxic HIV-1 components throughout the brain via extracellular vesicles (EVs). Our goal is to characterize these pathogenic EVs to begin to gain a better understanding of this EV-mediated pathology.

We took the first steps in developing a technique to assess the microRNA content of individual EVs but it needs to be heavily optimized to eliminate …

Immunobiology Of Adenovirus-Vector Vaccines For Mrsa, Emily Orvis

Master's Theses

Staphylococcus aureus is a gram-positive, extracellular bacterium that has emerged as an

important human pathogen. This bacterium is a leading cause of skin and soft tissue infections

(SSTIs) in humans, often leading to invasive and life-threatening infections. Treatment of S.

aureus infections is becoming more complicated due to the rise of methicillin-resistant S. aureus

(MRSA) strains, which are becoming increasingly resistant to a number of antibiotics. In the

United States, invasive MRSA infections result in more deaths annually than any other infectious

agent.

Despite a dire need, there is currently no vaccine against S. aureus infections. The failure

of past …

Chironomidae (Diptera) Community Structure In Lakes Of Contrasting Morphometry, Landscape Position, And Water Chemistry, Conrad Stanley Zack

Master's Theses

Chironomidae (Diptera) surface-floating pupal exuviae were collected monthly during the ice-free season in 2010-2011 from six lakes in the North Temperate Lakes Long-Term Ecological Research site in northern Wisconsin. The goal of this study was to determine whether chironomid community structure reflected differences in lake morphometry (i.e., depth, area, shoreline development, etc.), water chemistry, and/or landscape position (i.e., elevation). Forty-six genera were identified from four subfamilies: Chironominae (57%), Orthocladiinae (28%), Tanypodinae (11%), and Diamesinae (4%). Tanytarsus, Ablabesmyia, and Psectrocladius were found in all six study lakes; whereas certain genera, such as Omisus, Protanypus, and Epoicocladius were each observed in only …

Surveying Host Innate Immune Responses To Interferon Antagonist-Deficient Murine Coronaviruses, Aaron Brian Volk

Master's Theses

Two coronaviruses (CoVs)—severe acute respiratory syndrome (SARS) virus and Middle East respiratory syndrome (MERS) virus—have emerged in the 21st century from animal reservoirs into the human population, each causing an epidemic associated with significant disease and mortality. CoV epidemics are currently only controllable by rigorous public health measures; no targeted therapeutics or vaccines exist to treat or prevent any human CoV infection. One method of generating attenuated CoV strains to be studied as vaccine candidates involves specifically disrupting CoV-encoded interferon (IFN) antagonists, thereby rendering the virus vulnerable to host innate antiviral immunity. Deubiquitinating (DUB) activity encoded within CoV nonstructural protein …

Nitric Oxide Inhibits Biofilm Formation By Vibrio Fischeri Via The Nitric Oxide Sensor Hnox, Cecilia Thompson

Dissertations

Nitric oxide (NO) is an important signal secreted by the squid, Euprymna scolopes, and is thought to limit symbiotic biofilm formation, the initial step in colonization by the bacterium, Vibrio fischeri. Previous work demonstrated that a mutant defective for NO-sensor HnoX (heme nitric oxide/oxygen binding) had a competitive advantage over wild-type V. fischeri, but the mechanism by which this occurred remains unknown. HnoX is encoded upstream of hahK, a recently identified positive regulator of biofilm formation. I thus hypothesized that HnoX inhibits colonization by controlling HahK-induced biofilm formation during the initiation of colonization.

I assessed the impact of an hnoX …

Studying The Antagonistic Relationship Between Nkg2d And Tgf-Β Signaling In Cd8+ T Cells, Kushal Prajapati

Dissertations

Despite the remarkable success of cancer immunotherapies in treating patients with hematological cancers, the clinical response rates of immunotherapies in the case of solid tumors have been dismal. One major reason for the lower response rates is tumor-induced immune-suppression mediated by TGF-?, which directly suppresses the functionality of CD8+ T cells by inhibiting their activation, proliferation, and acquisition of inflammatory cytokines, granzyme B and perforin. On the other hand, NKG2D, a potent co-stimulatory receptor, has effects on CD8+ T cells opposite to that of TGF-?. In T cells from 22 healthy human donors, we found that the suppression by TGF-? …

Regulation Of Bacterial Glycogen Synthesis: Structure-Function Relationship Of Adp-Glucose Pyrophosphorylase, Hiral Priyank Patel

Dissertations

Starch is an important source for energy, and it has become a significant resource for bio-fuel production. ADP-glucose pyrophosphorylase is the enzyme that controls the synthesis of starch in plants, and glycogen in bacteria. This regulation is mainly driven by allosteric activators (Fru6P, FBP, and Pyruvate) in bacteria. It has been hypothesized that inter-subunit communications are important for the allosteric effect in this enzyme. Here we show that one specific subunit interface and the interaction between amino acids Arg11 and Asp141 are critical for the regulatory signal in the enzyme from Agrobacterium tumefaciens. Manipulation of this regulatory signal is critical …