Biology Commons^™

Iron Modulates Cell Survival In A Ras- And Mapk-Dependent Manner In Ovarian Cells, K. A. Bauckman, Edward M. Haller, I. Flores, M. Nanjundan

Integrative Biology Faculty and Staff Publications

Ovarian cancer is a leading cause of cancer death in women in the United States. While the majority of ovarian cancers are serous, some rarer subtypes (i.e. clear cell) are often associated with endometriosis, a benign gynecological disease. Iron is rich in the cyst fluid of endometriosis-associated ovarian cancers and induces persistent oxidative stress. The role of iron, an essential nutrient involved in multiple cellular functions, in normal ovarian cell survival and ovarian cancer remains unclear. Iron, presented as ferric ammonium citrate (FAC), dramatically inhibits cell survival in ovarian cancer cell types associated with Ras mutations, while it is without …

Bacterial Colonization And Extinction On Marine Aggregates: Stochastic Model Of Species Presence And Abundance, Andrew M. Kramer, M. Maille Lyons, Fred C. Dobbs, John M. Drake

Integrative Biology Faculty and Staff Publications

Organic aggregates provide a favorable habitat for aquatic microbes, are efficiently filtered by shellfish, and may play a major role in the dynamics of aquatic pathogens. Quantifying this role requires understanding how pathogen abundance in the water and aggregate size interact to determine the presence and abundance of pathogen cells on individual aggregates. We build upon current understanding of the dynamics of bacteria and bacterial grazers on aggregates to develop a model for the dynamics of a bacterial pathogen species. The model accounts for the importance of stochasticity and the balance between colonization and extinction. Simulation results suggest that while …

Net Effects Of Batrachochytrium Dendrobatidis (Bd) And Fungicides On Anurans Across Life Stages, Jenise Brown

USF Tampa Graduate Theses and Dissertations

Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease.

A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility …

Structure, Dynamics, And Evolution Of The Intrinsically Disordered P53 Transactivation Domain, Wade Michael Borcherds

USF Tampa Graduate Theses and Dissertations

in numerous disease states, including cancers and neurodegenerative diseases. All proteins are dynamic in nature, occupying a range of conformational flexibilities. This inherent flexibility is required for their function, with ordered proteins and IDPs representing the least flexible, and most flexible, respectively. As such IDPs possess little to no stable tertiary or secondary structure, they instead form broad ensembles of heterogeneous structures, which fluctuate over multiple time scales. Although IDPs often lack stable secondary structure they can assume a more stable structure in the presence of their binding partners in a coupled folding binding reaction.

The phenomenon of the dynamic …

Understanding Amphibian Decline: The Role Of Pesticides And The Pathogenic Chytrid Fungus On Amphibians And Aquatic Communities, Taegan A. Mcmahon

USF Tampa Graduate Theses and Dissertations

Amphibians are the most threatened taxon on the planet. Declines have been associated with over-exploitation, habitat loss, pollution, and pathogenic diseases, but of these factors, pollution and disease have been relatively under-studied. Here, I investigated: 1) the impacts of commonly used pesticides on aquatic communities, 2) the effect of these pesticides on amphibian susceptibility to the pathogenic chytrid fungus, Batrachochytrium dendrobatidis (Bd), and 3) whether there are non-amphibian hosts of Bd and 4) how to best quantify the survival of Bd through ontogeny of the host.

In my first research chapter, I quantified the effects of environmentally relevant concentrations of …

Phenotypic Characterization Of The Pancreatic-Derived Factor (Pander) Knockout Mouse On Pure C57bl/6 Background, Shari Moak

USF Tampa Graduate Theses and Dissertations

PANcreatic-DERived Factor (PANDER), or FAM3B, is a 235-amino acid protein strongly expressed within and secreted from the endocrine pancreas. Research surrounding PANDER has revealed a large role for the protein in maintaining glucose homeostasis, as evidenced by several Ad-PANDER overexpressing murine models, our lab's pancreas-specific PANDER transgenic overexpressor, and most recently our mixed genetic C57/129J PANDER knockout (PANKO) mouse. However, PANDER's overall role in glycemic regulation and glucose homeostasis has yet to be studied in a purebred C57BL/6J PANDER knockout model. Here we present the first phenotypic characterization of our global PANDER knockout mouse on a C57BL/6J background (PANKO-C57) where …

Resistance And Tolerance To Trematode Parasites In Larval Anurans, Brittany Sears

USF Tampa Graduate Theses and Dissertations

Nearly every species on the planet has at least one parasite, which, by definition, incurs a

cost in the host. Therefore, organisms must resist parasites - preventing or reducing infections -

or tolerate parasites - reducing the costs of infection - in order to maintain their fitness despite

the presence of parasites. Here, I investigated: 1) whether parasitic, larval trematodes (cercariae)

can detect the least resistant tadpole host species, 2) a hypothetical framework for how host life

history impacts the utilization of inflammation and thus, resistance and tolerance, 3) whether a

common anesthesia technique used in experimental infections immunocompromises tadpoles, …

Use Of Stable Isotope And Trace Metal Signatures To Track The Emigration Of Female Blue Crabs, Callinectes Sapidus, From Tampa Bay, Sky Barrington Williams

USF Tampa Graduate Theses and Dissertations

The blue crab, Callinectes sapidus, supports a successful fishery in the Atlantic Ocean and throughout the Gulf of Mexico, with a total landing of 8,158,788 lb. and a total value of $10,562,128 for the state of Florida during 2012 (FWC 2012 Annual Landings Summary). An accurate and comprehensive understanding of the blue crab's life history and seasonal migration behavior is essential in defining effective management strategies for the fishery. Tag recapture studies and ultrasonic tracking methods for studying blue crab migrations are costly in terms of time and resources. In this study an alternative approach, microchemical natural tagging, was …

Innate Immune Responses To Respiratory Syncytial Virus: Age-Associated Changes, Terianne Maiko Wong

USF Tampa Graduate Theses and Dissertations

Respiratory syncytial virus (RSV) infection causes ~64 million cases of respiratory disease and 200,000 deaths annually worldwide, yet there is no broadly effective prophylactic or treatment regimen. RSV can produce acute respiratory illness in patients of all ages but strikes the age extremes, infants and the elderly, with highest frequency presumably due to innate immune deficiencies. A higher morbidity and mortality has been reported for the elderly above 65 years of age, which has been attributed to immune senescence. Efforts to generate an effective vaccine have thus far been unsuccessful.

The innate immune system provides the first line of defense …

Growth And Herbivory Of The Black Mangrove, Avicennia Germinans, Along A Salinity Gradient, Danielle Neveu

USF Tampa Graduate Theses and Dissertations

Coastal communities will be most affected by global climate change and are important to study to understand current and future ecological processes. The current model for global climate change predicts a change in rainfall, which will alter the salinity of coastal systems. Given the presence of eutrophication in many coastal waters, it is important to understand the effects that this increase in nutrients, coupled with changes in salinity, will have on these communities. This study was conducted to understand the effect of salinity increase on the growth and herbivory of the black mangrove, Avicennia germinans, in the presence of …

Predation, Competition, And Nutrient Levels Affect The Survival Of Escherichia Coli, Enterococci And Enteric Pathogens In Aquatic Habitats, Pauline Wanjugi

USF Tampa Graduate Theses and Dissertations

Fecal indicator bacteria (FIB) such as Escherichia coli and enterococci are used to assess microbiological water quality in recreational waters worldwide. FIB are used with the assumption that their presence correlates with that of fecal-associated pathogens in recreational waters. In aquatic habitats, several factors can interfere with the predictive relationship between FIB and pathogens including extended survival of FIB in secondary habitats such as sediment, vegetation and sand. Furthermore, many biotic (e.g. predation from bacterivorous protozoa and competition from indigenous bacteria) and abiotic factors (e.g. temperature, salinity, ultraviolet (UV) light irradiation, and nutrient availability) can influence the fate of FIB …

Environmental Effects On The Biomechanics And Motor Physiology Of Elastically Powered Movements In Chameleons, Christopher Van Anderson

USF Tampa Graduate Theses and Dissertations

Environmental temperature exhibits profound effects on the activity and ecology of ectotherms through its impact on muscle contractile physiology. While the performance of locomotor behaviors powered by muscle contraction directly decreases by at least 33% over a 10°C drop in body temperature, chameleons are known to feed, presumably with high performance, at body temperatures where sympatric lizard species remain inactive. I propose that ballistic movements that are powered by the recoil of preloaded elastic and collagenous tissues are less thermally dependent than movements that rely on direct muscular power. Despite the reduced thermal sensitivity of the elastic-recoil powered movement, I …

The Mevalonate Pathway: A Potential Therapeutic Target For Jak2-Driven Myeloproliferative Neoplasms, Lori Nicole Griner

USF Tampa Graduate Theses and Dissertations

The Mevalonate Pathway: A Potential Therapeutic Target for JAK2-driven Myeloproliferative Neoplasms

Lori Nicole Griner

Abstract

Myeloproliferative neoplasms (MPNs) are diseases of hematopoietic stem cell origin and are characterized by uncontrolled growth of cells of the myeloid compartment. The Philadelphia chromosome negative classical MPNs, including polycythemia vera, essential thrombocythemia, and myelofibrosis, are diseases of dysregulated JAK2 signaling. In fact, the majority of MPN patients have activating mutations in JAK2 (e.g JAK2-V617F), a tyrosine kinase that contributes to the growth and survival of myeloid cells. While MPNs were first described over sixty years ago, a significant need remains to develop therapeutic strategies …

Ecological Interactions Influencing Avicennia Germinans Propagule Dispersal And Seedling Establishment At Mangrove-Saltmarsh Boundaries, Jennifer Mcclain Peterson

USF Tampa Graduate Theses and Dissertations

Mangroves and saltmarshes are ecologically important coastal ecosystems; unfortunately, these low-lying coastal ecosystems are vulnerable to global climate change. As sea-levels rise, mangroves are expected to shift their distribution landward towards higher elevation sites that are occupied by other plants, including saltmarsh taxa. Therefore, mangrove recruits at the leading edge of expansion may interact with diverse assemblages of saltmarsh plants, and these interactions could influence the success of mangrove encroachment into higher tidal-elevation areas. The purpose of the research presented here was to investigate empirically the ecological interactions that may influence the recruitment of the black mangrove, Avicennia germinans, …

The Role Of Molecular Chaperones In The Etiology And Treatment Of Psychiatric Diseases In The Elderly, John Clarence O'Leary

USF Tampa Graduate Theses and Dissertations

The elderly are at increased risk for developing psychiatric diseases, which include Alzheimer's disease, depression, anxiety and suicide. The probability of multiple disease comorbidity is also increased in the elderly. At the cellular level, the loss of protein homeostasis is often at the root of disease emergence, and thus the scientific community is searching for ways to help maintain this balance. A vast group of proteins that are paramount to balancing and counterbalancing protein levels is the molecular chaperone protein group, which has evolved a tremendous variety of functions in the cell. They aid in protein trafficking, folding, receptor signaling, …

An Investigation Of The Factors Leading To Invasion Success Of Non-Native Plants Using A System Of Native, Introduced Non-Invasive, And Invasive Eugenia Congeners In Florida, Kerry Bohl

USF Tampa Graduate Theses and Dissertations

The overwhelming majority of plant species introduced into a new range never become invasive. Consequently, identification of factors allowing the small fraction of successful invaders to naturalize, increase in abundance, and displace resident species continues to be a key area of research in invasion biology. Of the considerable number of hypotheses that have been proposed to resolve why some plant species become noxious pests, the enemy release hypothesis (ERH) is one of the most commonly cited. The ERH maintains that invasive plants succeed in a new range because they are no longer regulated by their coevolved natural enemies, and this …

Partial Characterization Of Pf13_0027: A Putative Phosphatase Of Plasmodium Falciparum, Christopher Campbell

USF Tampa Graduate Theses and Dissertations

Signal transduction and stage-specific gene expression are essential components of Plasmodium falciparum development. In this study, the putative phosphatase PF13_0027 is investigated as a critical component of intraerythrocytic development contributing to maturation of the late trophozoite. This putative phosphatase was identified during the course of a large-scale insertional mutagenesis project by insertion of the piggyBac (pB) element, containing a human dihydrofolate reductase (hDHFR) drug selection cassette into the open reading frame (ORF) preventing expression and attenuating parasite development. PF13_0027 codes for a protein with a rhodanese (RHD) and dual specificity phosphatase (DUSP) in a tandem arrangement typically identified with mitogen-activated …

The Effects Of Scaling On Bite Force And Suction Index In The Eastern Hellbender (Cryptobranchus Alleganiensis), Nicholas Patrick Larghi

USF Tampa Graduate Theses and Dissertations

The hellbender (Cryptobranchus alleganiensis) is a salamander that grows over a large range of body sizes (2-74 cm total length) making it an ideal organism for examining the effects of body size on morphology and performance. The goal of this study is to investigate the morphology changes over ontogeny and change in

feeding ability. Cryptobranchus feeds on small aquatic insects as juveniles and shifts to crayfish as they get larger. Morphology can be expected to change as an organism grows larger, and because morphology and performance are closely linked, this morphological change can result in a change in …

Investigation Of Hsf1 Interacting Partners Via A Genome-Wide Yeast Two-Hybrid Screen, Jamie Elizabeth Mendez

USF Tampa Graduate Theses and Dissertations

Heat shock factor 1 (HSF1) is the master transcriptional regulator of the heat shock response (HSR), an evolutionarily conserved cellular stress response. HSF1 promotes the expression of a variety of molecular chaperones that aid in restoring protein homeostasis upon exposure to proteoxic stress. However, all of the proteins responsible for regulating the HSR together with HSF1 are unknown. A genome-wide yeast two hybrid screen was performed to identify new S. cerevisiae Hsf1 protein interacting partners. Two GAL4 DNA binding domain-Hsf1 fusion proteins (baits) were constructed with mutations in the Hsf1 C-terminal activation domain to dampen Hsf1 mediated auto-activation of the …

Associational Resistance And Competition In The Asphondylia - Borrichia - Iva System, Keith Stokes

USF Tampa Graduate Theses and Dissertations

Indirect ecological effects such as associational resistance and resource competition have the potential to affect ecological interactions and influence the structure of ecological communities. Although resource competition is commonly studied, the effects of associational resistance are not as evident if studies are not designed to detect them. Additionally, the relative strengths of different ecological mechanisms ought to be measured in studies, rather than the strength of singular mechanisms. This permits proper attribution of causes and effects in community structure and detection of higher order interactions in a way that naïve reductionism will not.

In a series of experiments, I looked …

Drug Resistance Mechanisms To Gamma-Secretase Inhibitors In Human Colon Cancer Cells, Cindy R. Timme

USF Tampa Graduate Theses and Dissertations

Colorectal cancer is the third leading cause of cancer-related mortality. Much progress has been achieved in combating this disease with surgical resection and chemotherapy in combination with targeted drugs. However, most metastatic patients develop drug resistance so new modalities of treatment are needed.

Notch signaling plays a vital role in intestinal homeostasis, self-renewal, and cell fate decisions during post-development and is activated in colorectal adenocarcinomas. Under debate is its role in carcinomas and metastatic disease. In theory, blocking Notch activation using gamma-secretase inhibitors (GSIs) may show efficacy alone or in combination with chemotherapy in the treatment of colon cancer.

In …

Fungi Isolated From Niedźwiedzia Cave In Kletno (Lower Silesia, Poland), Rafał Ogórek, Agnieszka Lejman, Krzysztof Matkowski

International Journal of Speleology

Niedźwiedzia Cave is the most beautiful cave in Poland, discovered in a block of Cambrian marbles. It is the most important part of the reserve established in 1977. The cave is located within the Kłodzko Valley, in Śnieżnik Mt. Massif, in Kleśnica Stream Valley and was discovered in 1966 while working in a quarry. The study aimed at first mycological evaluation of the air and the rocks in Niedźwiedzia Cave. Nine species of filamentous fungi and a yeast species were isolated from the air sampled in the cave, whereas from the rocks - nine species of filamentous fungi and two …

Exploring The Sulfide Tolerance Of Ectosymbiotic Niphargus Amphipods From The Frasassi Caves, Central Italy, Jan Bauermeister, Karoline Assig, Sharmishtha Dattagupta

International Journal of Speleology

Two species of the crustacean amphipod genus Niphargus inhabit the sulfidic groundwaters of the Frasassi caves in central Italy, and both harbor filamentous, sulfide-oxidizing Thiothrix ectosymbionts. As sulfide is toxic to most aerobic organisms, it appeared possible that the ectosymbionts could help their Niphargus hosts with detoxification processes. In this study, mortality due to sulfide was compared between Niphargus individuals with ectosymbionts and individuals whose ectosymbionts had been killed by antibiotic treatment. Both Frasassi-dwelling Niphargus species revealed exceptionally high tolerances to sulfide compared to other amphipod species studied so far. Niphargus individuals without viable ectosymbionts tolerated sulfide levels exceeding those …

Effects Of Short Shoot Number And Presence Of An Apical Meristem On Rhizome Elongation, New Short Shoot Production, And New Rhizome Meristem Production Of Thalassia Testudinum Banks And Solander Ex König Planting Units In Tampa Bay., Michael Vearl Meads

USF Tampa Graduate Theses and Dissertations

Thalassia testudinum Banks and Solander ex König is the dominant seagrass in the Gulf of Mexico, Caribbean and the West Coast of Florida, yet little rhizome elongation, new short shoot production, or new rhizome meristem production data has been collected via direct measurement. A study of the rhizome growth of T. testudinum was completed in December 2004 in southern Tampa Bay that determined growth after 26.5 months. Two PVC planting frames each containing four rhizomes with 2 short shoots, two rhizomes with 4 short shoots, and two rhizomes with 8 short shoots were planted next to existing T. testudinum beds …

Reproductive Biology Of The Southern Dwarf Siren, Pseudobranchus Axanthus, In Southern Florida, Zachary Cole Adcock

USF Tampa Graduate Theses and Dissertations

The salamander family Sirenidae is composed of two extant genera, Siren and Pseudobranchus, each with two known species. Several questions regarding Sirenidae life history persist, and much of the available life history data for Pseudobranchus are attributed to studies of P. axanthus in northern Florida. Information on the reproductive biology of P. axanthus is limited, and historical references often suggest contradictory results. This study was undertaken to clarify information and expand on the limited data regarding P. axanthus reproductive biology, specifically for southern Florida populations. The study population was most likely the P. a. belli subspecies. P. axanthus in southern …

Availability And Quality Of Vegetation Affects Reproduction Of The Gopher Tortoise (Gopherus Polyphemus) In Improved Pastures, Anna Louise Hathaway

USF Tampa Graduate Theses and Dissertations

As part of a state-funded Gopher Tortoise (Gopherus polyphemus Daudin) translocation project, I monitored actively grazed improved pastures to determine if they could serve as suitable recipient sites for the threatened Gopher Tortoise displaced by human development. For cattle ranches to be considered suitable recipient sites females must be able to acquire sufficient energy to produce a clutch of viable eggs, and sufficiently high quality vegetation must be available to support juvenile recruitment into the population. Vegetation surveys were conducted to determine the composition and percent cover of plant species, especially those containing high amounts of nutrients, specifically nitrogen. Resident …

A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard

USF Tampa Graduate Theses and Dissertations

Abstract

Five sites in Tampa Bay, Florida, were sampled monthly from February 2006 to January 2007. These sites were located at the mouth of the Alafia River, in an inlet of Cross Bayou, on the easement of Gandy Bridge, near mangrove in Manatee County, and an inlet of Salt Creek, off Bayboro Harbor. Standard methods were used to determine shell height and Condition Index (CI). Intensity and prevalence of Perkinsus marinus were analyzed using Ray's Thioglycollate medium test, while Haplosporidium nelsoni was studied by histological examination. Histological methods were also used to determine sex ratios, reproductive phases, and egg diameters. …

Mitochondrial Dna Assessment Of The Phylogeography Of The Gopher Tortoise, Joshua R. Ennen, Brian R. Kreiser, Carl P. Qualls, Daniel Gaillard, Matthew Aresco, Roger Birkhead, Tracey Tuberville, Earl D. Mccoy, Henry R. Mushinsky, Thomas W. "Bill" Hentges, Aaron W. Schrey

Integrative Biology Faculty and Staff Publications

Identifying geographic barriers that define genetic structure within a species is crucial in formulating an effective conservation plan. The identification of appropriate management units is critical for the protection and recovery of the gopher tortoise Gopherus polyphemus, which have declined across their entire range. Previous molecular work at various spatial scales has identified distinct population assemblages of the gopher tortoise. The goal of this study was to assess the genetic structure in gopher tortoises through a more complete sampling of the federally listed as threatened portion of the range and evaluate the extent of genetic isolation imposed by several …

Dissolved Inorganic Carbon Uptake In Thiomicrospira Crunogena Xcl–2 Is Atp–Sensitive And Enhances Rubisco–Mediated Carbon Fixation, Kristy Jae Menning

USF Tampa Graduate Theses and Dissertations

Many autotrophic organisms living in environments with episodically low dissolved inorganic carbon (DIC) concentrations compensate for these fluctuations by employing a carbon concentrating mechanism (CCM). By utilizing a CCM, these organisms can generate intracellular DIC concentrations much higher than extracellular, thereby providing sufficient substrate for carbon fixation. Carbon concentrating mechanisms have been well-studied in cyanobacteria but studies are lacking in other autotrophs. The gammaproteobacterium Thiomicrospira crunogena XCL-2 is a hydrothermal vent chemolithoautotroph that has a CCM, which is functionally similar to that of cyanobacteria. At hydrothermal vents, DIC concentrations and pH values fluctuate over time, with CO2 concentrations ranging from …

Identification Of Amino Acids Essential For Estrone-3-Sulfate Transport Within Transmembrane Domain 2 Of Organic Anion Transporting Polypeptide 1b1, Nan Li, Weifang Hong, Hong Huang, Hanping Lu, Guangyun Lin, Mei Hong

School of Information Faculty Publications

As an important structure in membrane proteins, transmembrane domains have been found to be crucial for properly targeting the protein to cell membrane as well as carrying out transport functions in transporters. Computer analysis of OATP sequences revealed transmembrane domain 2 (TM2) is among those transmembrane domains that have high amino acid identities within different family members. In the present study, we identify four amino acids (Asp70, Phe73, Glu74, and Gly76) that are essential for the transport function of OATP1B1, an OATP member that is specifically expressed in the human liver. A substitution of these four amino acids with alanine …