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Nuclear Export Factor 3 Regulates The Localization Of Small Nucleolar Rnas, Melissa Wanling Li

Arts & Sciences Graduate Student Theses and Dissertations

Metabolic diseases, such as obesity and diabetes, are associated with excess levels of lipids, which can lead to organelle dysfunction, cell death and eventually organ dysfunction. This process, termed lipotoxicity, is still not completely understood. In a genetic screen used to identify genes critical for lipotoxicity, the Schaffer lab has identified small nucleolar RNAs (snoRNAs) within the ribosomal protein L13a (Rpl13a) locus that mediate the cellular response to lipotoxic and general metabolic stress. These snoRNAs are non-canonical in that they accumulate in the cytosol after metabolic stresses like lipotoxicity and oxidative stress, suggesting that cells have specific mechanisms for regulating …

Listeria Occurrence In Poultry Flocks: Detection And Potential Implications, Michael J. Rothrock Jr., Morgan L. Davis, Aude Locatelli, Aaron Bodie, Tori G. Mcintosh, Janet R. Donaldson, Steven C. Ricke

Faculty Publications

Foodborne pathogens such as Salmonella, Campylobacter, Escherichia coli, and Listeria are a major concern within the food industry due to their pathogenic potential to cause infection. Of these, Listeria monocytogenes, possesses a high mortality rate (approximately 20%) and is considered one of the most dangerous foodborne pathogens. Although the usual reservoirs for Listeria transmission have been extensively studied, little is known about the relationship between Listeria and live poultry production. Sporadic and isolated cases of listeriosis have been attributed to poultry production and Listeria spp. have been isolated from all stages of poultry production and processing. Farm studies …

Evolution And Metabolic Potential Of Francisella-Like Endosymbionts Of Ticks, Jonathan Graham Gerhart

Dissertations and Theses

Endosymbiosis in arthropods involves intracellular bacteria that supply an array of benefits to the host. Endosymbionts likely enhance the health of ticks by provisioning amino acids such as cysteine and tyrosine, and cofactors such as biotin and folic acid that are not available in blood--the sole nutrient source of ticks. Endosymbionts of ticks are of special interest due to their close evolutionary relationship with tick-vectored pathogens that impact livestock and human health. For example, ticks typically contain Coxiella-like endosymbionts (CLEs) that are the closest relatives of the human pathogen Coxiella burnetii. In order to understand the evolutionary relationship …

Microbiome Analysis Of Two Sympatric Fungus-Gardening Ants, Trachymyrmex Septentrionalis And Trachymyrmex Turrifex, Mattea Allert

Biology Theses

The fungus gardening-ant system is considered a complex, multi-tiered symbiosis between the ants, their fungus, and their corresponding microbes. We examine the bacterial microbiome of Trachymyrmex septentrionalis and Trachymyrmex turrifex ants and their corresponding fungus, using 16S rRNA, over a large geographical region to determine if horizontal transmission was occurring. The goals of this study was to determine how the ant microbiome was transmitted and how the fungus microbiome was transmitted. We determined that the microbiomes of T. septentrionalis and T. turrifex ants were different because of the species, while the microbiomes of T. septentrionalis and T. turrifex fungi were …

Simplifying Methods For In Vitro Metamorphosis Of Glochidia, Morgan A. Kern

Graduate Theses/Dissertations

Captive culture of Unionoid mussels is complicated by the parasitic larval stage, which normally requires a host fish for metamorphosis. Alternatively, some mussel species can metamorphose in vitro, i.e. in an artificial medium in Petri dishes. Most workers have used 5% CO₂ atmosphere and bicarbonate to stabilize pH, requiring a specialized incubator. In the present study, in vitro metamorphosis success of Anodonta oregonensis and other species were higher or similar in air than in 1%, or 5% CO₂. The nutritional role of the medium was tested by substituting physiological saline without nutrients at varying intervals before …

In Vitro Antiviral Activity Of Black Tea Polyphenols On Sindbis Virus In Vero Cells, Jose Villagomez

Theses, Dissertations and Culminating Projects

Black tea, derived from the Camellia sinensis plant, is a natural product that is rich in polyphenols. The major polyphenols found in black tea are known as theaflavins. Previous research demonstrated that theaflavins contain antiviral activity against Herpes simplex virus 1 & 2 (HSV-1 & HSV-2), both enveloped DNA viruses. The goal of this research was to investigate the antiviral activity of theaflavins on the Sindbis virus (SINV). SINV is an enveloped RNA virus, and the prototype species of alphaviruses. SINV was treated with various concentrations of a theaflavin rich Black Tea Extract (BTE) before infection of Vero Cells. Antiviral …

Regulation Of Haplid Phenotypes In Ustilago Maydis By Ammonium Transporters And Components Of The B Mating Locus., Rena Margaret Wallen

Electronic Theses and Dissertations

Fungi that can switch from budding to a filamentous infectious state have evolved mating type loci. Ustilago maydis, the maize pathogen, must mate with compatible partners possessing different alleles at two mating type loci for successful host infection. The a locus encodes pheromones and receptors, while the b locus encodes subunits of a heterodimeric transcription factor that regulates expression of virulence genes. Mating is triggered by environmental signals, including nutrient deprivation. My goal was to determine the fate of nitrogen starved haploid cells without a compatible mating partner. On solid low ammonium media, wild-type U. maydis filaments. I examined …

Oviposition Preference And Offspring Performance In Container Breeding Mosquitoes: Evaluating The Effects Of Organic Compounds And Laboratory Colonisation, David W. Allgood, Donald A. Yee

Faculty Publications

1. The preference–performance hypothesis (PPH) predicts that organisms lacking parental care should oviposit in habitats that optimise offspring performance. Preference–performance relationships were investigated for the Asian tiger mosquito (Aedes albopictus Skuse) and the southern house mosquito (Culex quinquefasciatus Say) (Diptera: Culicidae), two medically important container-breeding species, in response to an organic chemical blend mimicking decaying plant matter. Additionally, the effects of long-term laboratory colonisation of Cx. quinquefasciatus using wild and laboratory strains were evaluated.

2. Oviposition bioassays were conducted by releasing gravid mosquitoes into field enclosures with automobile tires containing low and high concentrations of the chemical blend, …

Clinical And Therapeutic Significance Of Obesity In Melanoma, Jennifer L. Mcquade

Dissertations and Theses (Open Access)

While the FDA approval of targeted and immune therapies in metastatic melanoma (MM) have dramatically improved outcomes in this disease, de novo and/or acquired resistance can limit the clinical benefit of these agents. The IGF-1/PI3K/AKT pathway has been implicated in resistance to both targeted and immune therapy. The IGF-1/PI3K/AKT pathway has also been shown to play a key role in the pathogenesis of obesity in other malignancies. To date, the impact of energy balance on clinical outcomes and therapeutic response in MM has not been studied. I hypothesized that energy balance would impact the molecular biology, behavior, and drug sensitivity …

A Study Of Salmonid Growth In Two Southern Appalachian Headwater Streams, Joshua Argo

Electronic Theses and Dissertations

This study sampled salmonid populations in two headwater streams in East Tennessee, Briar Creek and Left Prong Hampton Creek. Length and weight data were used to calculate the growth of these populations to determine if significant variation exists between isolated brook trout populations. Slope comparisons concluded that there was a difference in growth between brook trout populations of these streams (p

Nutritional, Endocrine, And Social Influences On Reproductive Physiology At The Origins Of Social Behavior, Karen M. Kapheim

Biology Faculty Publications

Understanding the evolutionary origins of social behavior in insects requires understanding the physiological basis for reproductive plasticity. Solitary bees and wasps or those living in small, flexible societies will be key to understanding how conserved pathways have evolved to give rise to reproductive castes. Nutrient-sensing and endocrine pathways are decoupled from reproduction in some life stages of social insects. Heterochrony, particularly as it is related to diapause physiology, may be an important mechanism by which this decoupling occurs. Additional research is needed to understand how these pathways became sensitive to cues from the social environment. Future research targeting species with …

Winter Diet Of Bobolink, A Long-Distance Migratory Grassland Bird, Inferred From Feather Isotopes, Rosalind B. Renfrew, Jason M. Hill, Daniel H. Kim, Christopher Romanek, Noah G. Perlut

Biology Faculty Publications and Presentations

Effective conservation of migratory bird populations depends on advancements in our understanding of processes throughout the life cycle. Fundamental information about wintering ecology (e.g., habitat use and diet composition) remains limited, which limits assessment of threats to populations during winter. Bobolink (Dolichonyx oryzivorus) is a year-round grassland obligate and Nearctic-Neotropical migrant that undergoes 2 complete molts each year, including a complete prealternate molt on the South American wintering grounds. This unusual winter molt provides a rare opportunity to examine, using stable isotope analysis, the timing and contribution of foraging resources in the Bobolink diet prior to northbound migration from disparate …

Evidence Of Language Prerequisites In Pan: Orofacial-Motor And Breath Control In Chimpanzees And Bonobos, Natalie Schwob

Master of Science in Integrative Biology Theses

Human spoken language requires the concomitant utilization of numerous cognitive and motor skills. Two particularly relevant skills are orofacial-motor control (OFM), the ability to purposefully move one’s facial muscles, and breath control (BC), subglottal air pressure that fuels sound production, as both are necessary in the voluntary production of speech. Many have claimed these competencies are uniquely human qualities without great ape antecedents. However, here we describe both skills in genus Pan, which contains our closest extant relatives: chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). We hypothesized that OFM and BC would be present in both species of Pan and …

Diet Specialization Does Not Explain Occupancy Or Abundance In A Test Of The Resource Breadth Hypothesis In A Small Mammal Community, Deborah R. Boro

Biology ETDs

The abundance-occupancy relationship (AOR) is a recurrent pattern in ecology and biogeography, in which species with expansive distributions are locally common while those with restricted distributions are locally rare. Despite occurring across a wide variety of taxa and spatial scales, the mechanisms underlying AORs are not well understood. I tested two such mechanisms regarding dietary generalism in a guild of 8 small, herbivorous African mammals: (1) the degree to which diet was explained by food availability, and (2) population-level diet breadth. I expected that food availability would better predict diet for abundant, widespread species than rare, restricted species. Additionally, I …

Disentangling Sources Of Variation In Ssu Rdna Sequences From Single Cell Analyses Of Ciliates: Impact Of Copy Number Variation And Experimental Error, Chundi Wang, Tengteng Zhang, Yurui Wang, Laura A. Katz, Feng Gao, Weibo Song

Biological Sciences: Faculty Publications

Small subunit ribosomal DNA (SSU rDNA) is widely used for phylogenetic inference, barcoding and other taxonomy-based analyses. Recent studies indicate that SSU rDNA of ciliates may have a high level of sequence variation within a single cell, which impacts the interpretation of rDNA-based surveys. However, sequence variation can come from a variety of sources including experimental errors, especially the mutations generated by DNA polymerase in PCR. In the present study, we explore the impact of four DNA polymerases on sequence variation and find that low-fidelity polymerases exaggerate the estimates of single-cell sequence variation. Therefore, using a polymerase with high fidelity …

The Design Of Giardia And The Genesis Of Giardiasis, Alan L. Gillen, Frank Sherwin

Faculty Publications and Presentations

Giardia is a genus of protozoa discovered in 1681. Six morphologically distinct species are recognized. It mainly attaches in the upper GI tract of a wide variety of vertebrates (including zebrafish), often with beaver and muskrat as reservoirs/carriers but exhibiting minimal—if any—disease in some animals. Giardia is usually non-pathogenic in the human population, even in children if exposed early in life. Although Giardia can be pathogenic, some strains colonize the gut with no malady. This parasite is not invasive and only serious infections depress the small intestine. Giardia are pear-shaped, have an adhesive disc for attaching to enterocyte cells in …

Fundamentals Of Human Anatomy And Physiology I Bio 220, Michael Cerbo

Library Impact Statements

No abstract provided.

Fundamentals Of Human Anatomy And Physiology Ii Lab Bio 223, Michael Cerbo

Library Impact Statements

No abstract provided.

Fundamentals Of Human Anatomy And Physiology I Lab Bio 221, Michael Cerbo

Library Impact Statements

No abstract provided.

Fundamentals Of Human Anatomy And Physiology Ii Bio 222, Michael Cerbo

Library Impact Statements

No abstract provided.

Effect Assessment Of Tio2 Nanoparticles Exposure On Medicago By Monitoring Morphophysiology, Charles Towey

Mahurin Honors College Capstone Experience/Thesis Projects

In recent years titanium dioxide nanoparticles (TiO₂NPs) have been ingredients in everything from paints to cosmetics, and even in some kinds of food. This growth in use has resulted in a substantial increase in the amount of titanium released into the environment, which could have detrimental effects on nearby plant and animal life. Currently, the number of studies conducted on the effects of TiO₂NPs is quite small, especially when it comes to edible crops. Because of this lack of research data, this study has been designed to assess the effect of TiO₂ NPs exposure on …

Effects On Campostoma Oligolepis Digestive Morphology And Gut Microbiota Composition Across A Gradient Of Urbanization, Hannah Grice

Master of Science in Integrative Biology Theses

Campostoma oligolepis, the Largescale Stoneroller, is a species of minnow native to northwest Georgia. This study investigated the impacts of urbanization on gut length and gut microbiota community composition in C. oligolepis from four small watersheds within the Etowah River drainage basin with different levels of impervious surface coverage (ISC). Individuals were collected from each sample site in the summer of 2016 between late July and early September. A second round of sampling was conducted in the fall between mid-October and mid-November. The gut length to total length ratio was calculated for each individual to allow for an unbiased …

The Interacting Roles Of Climate, Soils, And Plant Production On Soil Microbial Communities At A Continental Scale, M. P. Waldrop, J. M. Holloway, D. B. Smith, M. B. Goldhaber, Rebecca E. Drenovsky, K. M. Scow, R. Dick, D. Howard, B. Wylie, J. B. Grace

2017 Faculty Bibliography

Soil microbial communities control critical ecosystem processes such as decomposition, nutrient cycling, and soil organic matter formation. Continental scale patterns in the composition and functioning of microbial communities are related to climatic, biotic, and edaphic factors such as temperature and precipitation, plant community composition, and soil carbon, nitrogen, and pH. Although these relationships have been well explored individually, the examination of the factors that may act directly on microbial communities vs. those that may act indirectly through other ecosystem properties has not been well developed. To further such understanding, we utilized structural equation modeling (SEM) to evaluate a set of …

Foliar Mineral Accumulation Patterns Of Gypsophiles And Their Relatives From The Usa And Spain, Clare Muller

Masters Theses

Gypsum endemism in plants (gypsophily) is common on gypsum outcrops worldwide, but little is known about the functional ecology of Chihuahuan Desert gypsophiles. We investigated whether leaf chemistry of gypsophile lineages from the northern Chihuahuan Desert are similar to leaves of related non-endemic (gypsovag) species relative to their soil chemistry. We expected widely-distributed gypsophiles, hypothesized to be older lineages on gypsum, would have distinct leaf chemistry from narrowly-distributed, relatively younger lineages endemic to gypsum and gypsovags, reflecting adaptation to gypsum. We collected leaves from 23 gypsophiles and related non-endemic taxa growing on non-gypsum soils. Soils and leaves were analyzed for …

Risk-Averse Personalities Have A Systemically Potentiated Neuroendocrine Stress Axis: A Multilevel Experiment In Parus Major, Alexander T. Baugh, Rebecca A. Senft , '15, Marian L. Firke , '14, Abigail P. Lauder , '15, J. Schroeder, S. L. Meddle, Kees Van Oers, M. Hau

Biology Faculty Works

Hormonal pleiotropy—the simultaneous influence of a single hormone on multiple traits—has been hypothesized as an important mechanism underlying personality, and circulating glucocorticoids are central to this idea. A major gap in our understanding is the neural basis for this link. Here we examine the stability and structure of behavioral, endocrine and neuroendocrine traits in a population of songbirds (Parus major). Upon identifying stable and covarying behavioral and endocrine traits, we test the hypothesis that risk-averse personalities exhibit a neuroendocrine stress axis that is systemically potentiated—characterized by stronger glucocorticoid reactivity and weaker negative feedback. We show high among-individual variation and covariation …

Foundations Of Biology (Ghc), Tom Harnden, Sharryse Henderson, Andrew Dawson, Jason Christian, Greg Ford, Christin Collins

Biological Sciences Grants Collections

This Grants Collection for Foundations of Biology was created under a Round Five ALG Textbook Transformation Grant.

Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.

Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials:

• Linked Syllabus
• Initial Proposal
• Final Report

Role Of Terrestrial Organic Matter In Food Webs Of The Rocky Intertidal Zone, Douglas O. Fairbanks

Theses and Dissertations

Terrestrial organic matter (TOM) constitutes an important source of energy in many aquatic environments (streams, lakes, wetlands). This is the first study to examine the role of TOM in food webs of the rocky intertidal zone. We compared the consumption of red alder leaves (Alnus rubra) to common marine sources of drifting detritus along the southern Oregon coast (Nereocystis luetkeana, Phyllospadix spp., and Fucus gardneri). We used short term (hours to days) and long term (months) feeding experiments to compare the rate of consumption among each plant species during the Spring and Fall of 2014 …

Central Precocious Puberty Alters The Mammary Gland Epithelial Landscape In Female Rats, Alina M. Hamilton

Theses and Dissertations

Precocious puberty (PP) is a serious endocrine disorder associated with an increased risk for development of breast cancer (BC) later in life. However, the lack of a strong in vivo model has made it difficult to study this relationship. Our group has established manganese (Mn) as a non-toxic activator of the pubertal process. Recently we demonstrated that Mn-induced precocious puberty (MnPP) accelerates E2-regulated mammary gland (MG) development in prepubertal female rats, resulting in persistent proliferation and adult hyperplasia. Using this model, I demonstrate that precocious puberty alters steroidal regulation of proliferation in both the prepubertal and adult virgin MG, altering …

Bacterial Community Ecology Of The Colon In Mus Musculus, Rachel Marie Nettles

Theses and Dissertations

The gut microbiome is a community of closely interacting microbes living in the gastrointestinal tract. Its structure has direct relevance to health. Disturbances to the microbiome, such as due to antibiotic use, have been implicated in various diseases. The goal of this study was to determine how the gut microbiome reacts to and recovers from disturbance caused by antibiotics. Because diet also influences the microbiome, this study included the interaction between diet and antibiotics. Half of the mice in each diet treatment were given antibiotics to disturb their microbiomes. After cessation of antibiotics, mice were paired in combinations within diets …

Symbiosis With Nitrogen-Fixing Rhizobia Influences Plant Defense Strategy And Plant-Predator Interactions, Adrienne Louise Godschalx

Dissertations and Theses

As sessile organisms, plants evolved a plethora of defenses against their attackers. Given the role of plants as a primary food source for many organisms, plant defense has important implications for community ecology. Surprisingly, despite the potential to alter entire food webs and communities, the factors determining plant investment in defense are not well-understood, and are even less understood considering the numerous symbiotic interactions in the same plant. Legume-rhizobia symbioses engineer ecosystems by fixing nitrogen from the atmosphere in trade for plant photosynthates, yet connecting symbiotic resource exchange to food web interactions has yet to be established. Here I test …