Biology Commons^™

The Thermodynamics And Structure Of Tumor Suppressor P53 And Helical Mutants Binding To Inhibitors Mdm2 And Mdmx At The Primary And Secondary Sites, Pirada Serena Higbee

USF Tampa Graduate Theses and Dissertations

p53 is an intrinsically disordered protein that is a tumor suppressor. The transactivation domain is split into two parts (TAD1 and TAD2). These TADs bind to inhibitors MDM2, and a homolog, MDMX, but TAD1 binds with greater affinity. MDM2 is an E3 ubiquitin ligase that leads to the degradation of p53. MDMX is not an E3 ubiquitin ligase, but it does prevent p53 from binding to DNA, thus preventing its tumor suppressor role.

Previous research showed that increasing p53 helicity by mutating prolines to alanines increased p53's helicity but not the length of the helix. The increase in helicity increased …

Thermal Ecology And Swimming Performance Of Native Tadpoles Dryophytes Femoralis In Central Florida, Jessalyn Aretz

USF Tampa Graduate Theses and Dissertations

Urbanization and climate warming have contributed to global amphibian declines in recent decades. Amphibians are particularly vulnerable to climate and urban-induced warming because their physiological processes are dependent on temperature across all life stages, but few studies have been done on tadpole responses to warming in comparison to adult responses. The study objective was to determine how the thermal ecology and swimming performance of a native Florida tadpole varied with rearing temperature and urban level, and whether these traits are plastic or adaptive. We collected eggs from wild populations of pine woods treefrog (Dryophytes femoralis) tadpoles at an urban and …

An Analysis Of Florida Manatee (Trichechus Manatus Latirostris) Rescues (1993-2022) With Recommendations For Future Rehabilitation Program Needs, Katherine Frisch

USF Tampa Graduate Theses and Dissertations

Florida manatees (Trichechus manatus latirostris) are threatened marine mammals that inhabit the coastal and near shore waters along the southeastern United States, primarily Florida. Manatee conservation is multi-faceted. One component of the manatee recovery program is the rescue and rehabilitation program that provides care for sick, injured and orphaned manatees. The science of conservation biology, whose goal is to maintain biodiversity using a multidisciplinary approach, can be applied to aspects of the manatee rescue and rehabilitation program.

A federally authorized, state implemented, rescue system has been in place for many years to rescue and treat injured and orphaned animals. Rescued …

Under Pressure: The Soft Robotic Clap-And-Fling Of Cuvierina Atlantica, Daniel Mead

USF Tampa Graduate Theses and Dissertations

Evolution over billions of years has led to unique animals of all types. The tiny sea butterfly is one that remains mostly anonymous because of its size and low place on the food chain, but it is a swimming creature that when examined closely reveals a surprise. Shockingly, it has a swimming motion nearly identical to small insects flying at intermediate Reynolds numbers, referred to as the clap-and-fling. The centimeter long pteropod flapping briskly at 5Hz escapes attention with its size and speed. Modeling the clap-and-fling motion of the sea butterfly at a larger scale allows the benefits and uniqueness …

Health Status In An Urban-Dwelling, Subtropical Frog Species (Lithobates Sphenocephalus) And Its Relation To Ranavirus And Hemoparasites, Gabrielle M. Wickersham

USF Tampa Graduate Theses and Dissertations

Urbanization poses significant challenges to wildlife, including amphibians. The present study uses a multi-parameter approach that incorporates veterinary techniques to investigate the current health status of the adult southern leopard frogs (Lithobates sphenocephalus) in Tampa Bay, Florida, amidst urban stressors including nutrient loading, fragmented habitats, and light and noise pollution. Novel values for fluctuating asymmetry (e.g., variation between left and right bilateral traits; FA), body condition (CF), stress (e.g., neutrophil:lymphocyte (N:L) ratio), and inflammation (e.g., neutrophil morphologic abnormalities, parasite load) are reported. I also investigate the relationship of overall health with ranavirus presence and hemoparasite infections. Ranavirus was absent in …

Human Motion Detection Evaluated Through An Evoked Cortical Potential Frequency Spectrum, Howard E. Painter

USF Tampa Graduate Theses and Dissertations

Electrical potentials were recorded from scalp of normal male subjects while they were viewing continuously moving sinusoidal gratings. Responses from the occipital cortex were amplified, digitized, stored and then transformed from the time domain to the frequency domain using a microcomputer based Fast Fourier Transform algorithm. High frequency components (Beta Activity) of the resulting power spectrum were analyzed for evidence on neural generators (electrical sources) in the striate cortex driven presumably by transient-cells (Y-cells or Magnocellular) responding to the continuously moving grating. Several stimulus parameters were examined: angular velocity, spatial frequency, direction (orientation), color, and intensity. A16 Hz component of …

Book Review: Kings, Conquerors, Psychopaths: From Alexander To Hitler To The Corporation, Tim Bakken

Genocide Studies and Prevention: An International Journal

The book Kings, Conquerors, Psychopaths is a survey of a vast amount of human wrongdoing. It lays bare the motivations of aggressors who wish to subjugate nations or groups of people and corporate executives and government bureaucrats who make discretionary decisions that harm people. Along with cataloging mass killings by despots and soldiers, the book includes stories about Ponzi-schemers and the deaths of automobile drivers and passengers who were killed by vehicle defects known to the manufacturer. The book posits that “[p]owerful, elite forces are trying to force us backward toward a non-democratic state, one where power, wealth, and prerogative …

Targeting Bet Proteins Downregulates Mir-33a To Promote Synergy With Pim Inhibitors In Cmml, Christopher T. Letson

USF Tampa Graduate Theses and Dissertations

Chronic Myelomonocytic Leukemia (CMML) is a rare myeloid malignancy with a dismal prognosis and no therapeutic options which are capable of altering the natural course of the disease. There remains a significant need for novel therapies that are able to meaningfully improve patient outcomes. In this study we explore the effectiveness of Bromodomain and Extra-Terminal domain protein inhibitor (BETi) combinations in CMML. Preclinical studies in myeloid neoplasms have demonstrated efficacy of BETi. However, BETi demonstrate poor single agent activity in clinical trials. Several studies suggest that combinations with other anti-cancer inhibitors may enhance the efficacy of BETi. To nominate BETi …

Brain Metastasis-Associated Fibroblasts Secrete Fucosylated Pvr/Cd155 That Induces Breast Cancer Invasion, Emma Adhikari

USF Tampa Graduate Theses and Dissertations

Breast cancer (BC) continues to be the most diagnosed cancer and the second leading cause of cancer deaths in women worldwide. High mortality, in most cancers, is due to metastasis; BC is the most common source of one of the deadliest forms of metastasis–brain metastasis (BM) in female. Patients with triple negative breast cancer (TNBC) exhibit the highest incidence of BM and poorest survival outcomes upon diagnosis with BM. The prognosis of breast cancer brain metastasis (BCBM) remains poor because the blood–brain barrier (BBB) prevents the uptake of drug substances, including chemotherapeutic agents, targeted agents, and toxins, from the brain. …

Hurricanes And Tropical Storms’ Impact On Water Quality In Lake Okeechobee, Florida, Daniela Vasquez Diaz

USF Tampa Graduate Theses and Dissertations

Hurricanes are natural events with catastrophic outcomes, while climate change's effects on their intensity and frequency remain discussed. However, it is crucial to analyze these through models and statistics to understand their behavior and impact on the basins. Particularly in lakes on tropical coasts since disruptive events such as hurricanes tend to be highly affected. Lake Okeechobee is a unique lake located in Florida and one of the largest freshwater lakes. The lake and some of its significant stations are the locations chosen to perform the investigation. The main focus of the investigation is determining the effect that hurricanes have …

Patterns In Biodiversity And Community Assemblage In Macrofaunal Fouling Communities On Tampa Bay Floating Docks, Cassidy C. Bell

USF Tampa Graduate Theses and Dissertations

Understanding biodiversity trends of highly disturbed urban landscapes is essential as anthropogenic factors continue to drive global biodiversity loss. Within marine ecosystems, macrofaunal fouling communities, aggregations of epibenthic invertebrates that colonize human-made structures, represent an ecologically important subset of urban coastlines. Tampa Bay is a highly urbanized estuary in Florida, USA, and is home to the state’s largest port, Port Tampa Bay. This makes the bay a prime site for the introduction of new species, with many organisms either considered invasive or cryptogenic, their origins left unclear. Many factors may contribute to the communities that form on urban structures including …

Spatial Structure Of Germination And Seed-Associated Fungi In Tropical Pioneer Seeds, Daniela Varon Garcia

USF Tampa Graduate Theses and Dissertations

Negative density-dependent regulation is the process by which host-specific natural enemies reduce the survival of seeds and seedlings of conspecifics near adult trees, favoring heterospecific recruitment, and ultimately increasing local diversity. Negative density-dependent regulation by fungal pathogens has been consistently reported to promote plant diversity in the tropics, even though they tend to be multi-host and host-specificity is rarely reported. Nevertheless, evidence suggests that host-generalist fungi can have host-specific effects that produce disproportionate negative effects on some plant species but not others, promoting regional diversity. However, such studies have not tested for both host-specificity and distance-dependent effects in fully replicated …

Distinct Nrf2 Signaling Thresholds Mediate Lung Tumor Initiation And Progression, Janine M. Deblasi

USF Tampa Graduate Theses and Dissertations

NRF2 is a redox-responsive transcription factor the directs the antioxidant program and several critical metabolic processes. Mutations in NRF2 or its negative regulator KEAP1 occur in up to one third of non-small cell lung cancers (NSCLCs) and are often associated with resistance to therapy and poor outcomes. In the present studies, murine alleles of the Keap1 and Nrf2 mutations found in human NSCLC were developed and I comprehensively investigated their impact on tumor initiation and progression. I observed that chronic Nrf2 stabilization by Keap1 loss-of-function or Nrf2 activating mutation was not sufficient to cause lung tumor initiation, even when p53 …

Resource Recovery From Crew Metabolic Wastes In Lunar And Martian Habitats: Reuse Of Effluent From An Anaerobic Membrane Bioreactor Treating Fecal Organic Matter As Fertilizer Source For Plants, Alexandra A. Smith

USF Tampa Graduate Theses and Dissertations

As humans set their sights on exploration of the Moon and Mars human focused challenges like providing potable water, supplying nutritious food to the astronaut crew, and managing their waste present themselves. There are no readily available resources on the Moon and Mars, therefore nothing should be considered unusable including the organic wastes (i.e., feces and urine) produced by the crew. Fecal matter is not currently recycled and is treated as solid waste. After collection, it is discarded out of the International Space Station where it is incinerated upon re-entry. This approach will not work on the Moon’s surface. There …

Examination Of Microplastics And Organic Contaminants In Tampa Bay’S Eastern Oyster (Crassostrea Virginica) Through Visual And Chemical Analysis, Andrea Murray

USF Tampa Graduate Theses and Dissertations

Microplastic pollution is an increasingly alarming concern with widespread global distribution in aquatic environments. Filter feeding organisms such as bivalves, have a heightened risk of microplastic ingestion through free floating particulates in the water. This can lead to bioaccumulation moving up through trophic levels to apex predators and humans. Spatial and temporal differences in microplastic abundance were evaluated in the Eastern Oyster, Crassostrea virginica, at six sites within Tampa Bay. Oyster tissue was digested using 30% hydrogen peroxide (H2O2) and microplastics were quantified using Nile Red dye and fluorescent particle excitement. A total of 3025 microplastics were found throughout six …

Statistical Analysis Of Ribonucleotide Incorporation In Human Cells, Tejasvi Channagiri

USF Tampa Graduate Theses and Dissertations

During the DNA replication process, ribonucleotides, the building blocks of RNA, may be occasionally incorporated in the newly synthesized DNA. DNA is primarily composed of deoxyribonucleotides and there exist cellular mechanisms for removing ribonucleotides from DNA, which may point towards ribonucleotide incorporation being a replication error. Further, an excess of these ribonucleotides in the genome has been known to lead to genomic instability and has been implicated in human diseases. However, there are also hypotheses that suggest that ribonucleotides may be beneficial in certain circumstances. In this study we examine ribonucleotide incorporation in the human genome in several human cell …

The Role Of The Dna Helicase Rrm3 Under Replication Stress, Julius Muellner

USF Tampa Graduate Theses and Dissertations

DNA replication needs to be strictly monitored to ensure proper duplication of the genome. During DNA synthesis, the DNA replication machinery encounters multiple obstacles such as incorrect dNTP incorporation, RNA-DNA hybrids, modification of DNA nucleobases, collision with the transcription-replication machinery. These endogenous and exogenous sources of DNA damage may result in single-strand breaks (SSBs) and double-strand DNA breaks (DSBs), thereby impeding fork progression. To prevent stalling of DNA synthesis a multitude of DNA repair pathways are specifically designed to deal with these kinds of blockages. One of the proteins involved in ensuring DNA replication fork progression is the DNA helicase …

Histone Deacetylase 8 Is A Novel Therapeutic Target For Mantle Cell Lymphoma And Preserves Natural Killer Cell Cytotoxic Function, January M. Watters

USF Tampa Graduate Theses and Dissertations

This study demonstrates for the first time that HDAC8 function is critical for MCL survival, and abrogating its activity in human primary NK cells does not interfere with NK IgG antibody directed ADCC therapies ex vivo. Human NK cells, isolated from healthy donors, are highly resistant to HDAC8 inhibitor treatment with PCI-34051. Even at the highest concentration, 20uM, no toxicity was observed. Conversely, MCL cell lines representative of the aggressive MCL subtype, classical MCL, were especially sensitive to PCI-34051, an HDAC8 selective inhibitor, treatment. Blocking HDAC8 activity and/or abrogating expression through shRNA silencing induced significant DNA damage, hyperacetylation of SMC3, …

Comparing Mortality In Response To Simulated Climate Change In The Harvester Ant, Pogonomyrmex Badius, And The Fire Ant, Solenopsis Invicta, Haley Depner

USF Tampa Graduate Theses and Dissertations

With the rapid transport of plants, produce, and goods out of its South American home, the fire ant, Solenopsis invicta, has invaded continents on a global scale. In the United States alone, S. invicta is responsible for an estimated $1 billion in damages annually. In contrast to the invasive fire ant, Florida’s native harvester ant, Pogonomyrmex badius, is a keystone seed disperser, providing seed relocation benefits to Florida’s sandhill wildfire-adapted habitats. Seed relocation reduces seedling competition for nutrients with the parent plant, reduces predation of seeds by rodents, increases nutrient loads associated with ant mound soils, and protects seeds from …

Diatom Diversity And Functional Groups In 72 Florida Lakes: Assessing Ecological Changes For Improved Protection And Management, Francesca M. Lauterman

USF Tampa Graduate Theses and Dissertations

Florida lakes are diverse ecosystems and are an important part of the state's biodiversity and ecosystem services. As human population and development increase across the state, many lakes have been documented as nutrient impaired and are unable to maintain essential ecological functions. In this study, diatom diversity and functional groups in 72 Florida lakes were assessed for their relationships with associated water-quality data. Common alpha diversity indices, including Shannon-Weiner Index, the Gini-Simpson Index, and Hill’s numbers were utilized to measure trends in diatom communities, while the relationships between diatom lifeform characteristics and environmental data were explored using multivariate methods and …

Population Demography, Spatial Ecology, And Habitat Use Of The Florida Box Turtle (Terrapene Bauri) On A Barrier Island, Michael D. Mills

USF Tampa Graduate Theses and Dissertations

Turtles are one the most threatened vertebrate groups in the world due to anthropogenic threats such as habitat loss and overexploitation. In addition to occupying a range that has been vulnerable to major habitat loss, the Florida box turtle (Terrapene bauri) is particularly at risk of overexploitation due to its popularity in the pet trade. Sanibel Island is a barrier island in southwest Florida that has experienced major habitat loss and is the site of a recent poaching event. In response to these threats, studies of both the population demography and spatial ecology were conducted on Sanibel’s Florida box turtle …

Reproduction In Relation To Heavy-Metal Contamination Along An Urbanization Gradient In Aninvasive Florida Lizard Species (Anolis Sagrei), Elizabeth Hauck

USF Tampa Graduate Theses and Dissertations

Environmental contamination is accumulating rapidly worldwide due to increasing urbanization rates. Heavy metals are known to be particularly toxic to organisms, to accumulate in biological systems, and to be found in higher concentrations in animals located in areas of high urban levels. However, the physiological impacts of these toxic heavy metals in wildlife remain largely unknown. Lizards are excellent bioindicator species for environmental contaminants due to their trophic level as mesopredators and their susceptibility of exposure via air, water, diet, and soil through egg deposition. To assess the impacts heavy-metal contamination has on reproductive parameters in lizards and how these …

The Biological Roles Of Tau Protein In The Vasculature And The Regulation Of Vegfr1 Signaling By Heparan Sulfate, Yanan Zhu

USF Tampa Graduate Theses and Dissertations

My dissertation consists of two research projects. The first project investigated the roles of extracellular tau in the vasculature, including tau-induced angiogenesis and tau internalization, a topic related to tauopathy. The second project was to understand the regulatory functions of heparan sulfate proteoglycans in VEGFR1 signaling.

Tauopathies are a class of neurodegenerative diseases, including Alzheimer's disease, and are characterized by the appearance of intraneuronal tau inclusion in the brain and the patient's cognitive decline. Recent studies have emerged that soluble and aggregated tau also exists outside neurons in the central nervous system. Intriguingly, overexpressing tau in neurons in the mouse …

Investigating Students' Interpretations Of Ecological Food Webs, Christopher Neil Grissett

USF Tampa Graduate Theses and Dissertations

To better prepare undergraduate students for current and future biological challenges, scientists, educators and researchers in the Vision and Change report recommended five core conceptual areas essential for the improvement of biological literacy, one of which is biological systems. Systems are an identified core concept that may help promote biological literacy. One example of a system that students have difficulty understanding is an ecological food web, which consists of parts or components interacting with one another to perform a given phenomenon. The intricacies of this system tend to confuse students and can produce naïve conceptions that could hinder future learning …

Design And Assessment Of A Novel Edna Survey Method For The Eastern Indigo Snake (Drymarchon Couperi), Emily K. Galbraith

USF Tampa Graduate Theses and Dissertations

1. Accurate information about species range declines is the cornerstone of effective conservation when habitat loss drives biodiversity loss. The Eastern Indigo snake (Drymarchon couperi) is an apex predator in Florida and, like many other native Florida species, is threatened by widespread habitat destruction. Environmental DNA (eDNA) monitoring of this elusive snake would provide a low-risk and low-cost approach to expand our knowledge of the species’ range and distribution.

2. We designed and tested an eDNA assay that can detect the presence of Eastern Indigo snake from soil samples of their natural habitat. This assay was …

Utilizing Maternal Investment Strategies Of Sharks To Develop Management Tools To Aid In Shark Conservation, Dennis Deeken

USF Tampa Graduate Theses and Dissertations

Every generation, breeding females and males repopulate ecosystems with the next generation of offspring. Two models link maternal investments in offspring size and number to natural selection processes. In unstable resource environments, bet-hedging models predict a conservative tradeoff in maternal investments resulting in moderate egg size and clutch size within a given range of sizes for a given species. r/K selection models make predictions on maternal investments across species. In unstable resource environments, r-selected species invest in large broods of small offspring. In stable environments, K-selected species invest in small broods of large offspring. The maternal risk management model predicts …

Ec Expression Of Activated K-Ras Leads To Capillary Deficiency Due To Excessive Lumen Formation, Reduced Pericyte Recruitment, And An Increased Susceptibility To Mmp-1-Dependent Vascular Regression, Zheying Sun

USF Tampa Graduate Theses and Dissertations

Activated k-Ras mutations play a role in a variety of pathological conditions, such as arteriovenous malformations (AVMs). To study the effect of activated k-Ras mutation on lumen formation, we engineered human ECs to simultaneously express the activated k-Ras (G12V) mutation and compared their ability to form lumens with control ECs. We demonstrated that ECs with k-RasV12 lead to marked stimulation of EC lumen formation due to dramatic increases in intracellular vacuole formation and fusion, signaling changes including accelerated Src kinase activation, and MT1-MMP-dependent lumen expansion, all of which drive the process of lumen formation. The markedly accentuated lumen formation is …

Interactions Between Juvenile Estuary-Dependent Fishes And Microalgal Dynamics, Ian C. Williams

USF Tampa Graduate Theses and Dissertations

The ontogenetic movement of juvenile estuary-dependent fishes upstream in estuarine settings is a phenomenon observed around the world. These movements usually coincide with a shift in diet from smaller prey, such as calanoid copepods, to larger prey, such as mysids. However, the mechanism that drives this pattern has yet to be conclusively described. Prior to the current study, zooplankton/hyperbenthos (“zooplankton”), primary production, and water quality data were collected from the Caloosahatchee River estuary in two concurrent and coordinated studies over a two-year period. One of the products of these sampling efforts was a classification of primary-producer types at the sediment-water …

A Holistic Investigation Of Acidosis In Breast Cancer, Bryce Ordway

USF Tampa Graduate Theses and Dissertations

In the early 20th century, Nobel laureate Otto Warburg made the observation that cells of a carcinoma had considerably higher glycolytic metabolism and considerably lower oxidative metabolism compared to cells of a normal tissue. He postulated that within this observation was the key to deciphering the differences between malignant and normal tissue. It is now well established that tumors of the breast are unequivocally acidic, caused by an abnormal amount of aerobic glycolysis, colloquially known as the Warburg effect. Over the last decades, our group, led by Dr. Robert J. Gillies, has set out to characterize the causes and consequences …

X-Linked Ubiquitin-Specific Peptidase 11 Increases Tauopathy Vulnerability In Women, Yan Yan

USF Tampa Graduate Theses and Dissertations

Women experience significantly higher tau burden and increased risk for Alzheimer’s disease (AD) than men, yet the underlying mechanism for this vulnerability has not been explained. Here, we demonstrate through in vitro and in vivo models, as well as human AD brain tissue, that X-linked ubiquitin specific peptidase 11 (USP11) augments pathological tau aggregation via tau deubiquitination initiated at lysine-281. Removal of ubiquitin provides access for enzymatic tau acetylation at lysines 281 and 274. USP11 escapes complete X-inactivation, and female mice and people both exhibit higher USP11 levels than males. Genetic elimination of usp11 in a tauopathy mouse model preferentially …