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The Regulation Of Prospore Membrane Shape In Saccharomyces Cerevisiae, Emily M. Parodi

Graduate Doctoral Dissertations

The size and shape of a membrane is an important determinant in cell morphology. My work focuses on how membrane size and shape is determined, using the budding yeast S. cerevisiae as a model. During sporulation in S. cerevisiae, the diploid cell remodels its interior such that four spores are formed within an ascus. During this remodeling process, the prospore membrane is synthesized de novo and grows to surround each of the meiotic products. The prospore membrane is a double lipid bilayer and ultimately determines the sizes and shapes of the newly formed spores. My work focuses on the …

The Processing Of Amyloid Precursor Protein In The Central Nervous System Of Humans And Rhesus Macaques, Justyna Anna Dobrowolska

All Theses and Dissertations (ETDs)

Alzheimer's disease: AD) is the most common dementia, currently afflicting 30 million people worldwide, with prevalence steadily increasing. Over 99% of AD cases are classified as sporadic, in which the major risk factors are age: greater than 65 years) and the ApoE-ε4 allele: in a gene dose dependent manner). The minority of AD cases: less than 1%) are caused by autosomal dominant inheritance of a genetic mutation in one of three genes: Amyloid Precursor Protein: APP), Presenilin-1: PSEN1), or Presenilin-2: PSEN2). Mutation carriers will generally notice cognitive decline starting at a relatively young age, anytime between their 30s-50s, and eventually …

The Effects Of Nesting Environment On Neonatal Hypoxic-Ischemic Injury, Laura Grace Rollins

Graduate Masters Theses

Term neonates with hypoxic-ischemic (HI) injury are at risk for devastating neurological sequelae. The objective of this study is to determine if altering the early environment for maternal care-taking impacts the immediate and long-term sequelae of HI offspring. The Rice-Vannucci model was used to induce HI in postnatal day (PND) 7 Long-Evans pups. Litters were assigned to a closed nest (CN) or normal standard housing (SH) condition. Neurobehavioral development, cognitive ability, and stress response were assessed to establish any benefits of the CN condition. Finally, postmortem brain tissue was analyzed for morphometric markers of injury.

The Function Of Carmil1 In Migrating Cells, Marc Edwards

All Theses and Dissertations (ETDs)

This dissertation describes the physiological role of the Capping Protein- CARMIL interaction in migrating cells. I establish the CARMIL-CP complex as a key regulator of lamellipodial actin assembly and of lamellipodial dynamics. Membrane ruffling at the leading edge of motile cells and macropinocytosis were also found to be dependent on the CARMIL1-CP interaction. This is consistent with macropinocytosis and ruffling being dependent on a functional and dynamic lamellipodium.: Kerr and Teasdale, 2009).

In chapter two I demonstrate that the CBR of CARMIL1 is competent to inhibit CP in cells. I show that overexpression of the CBR in cells leads to …

Understanding Crx-Associated Retinopathies Using Animal Models, Nicholas Minh Abell Tran

All Theses and Dissertations (ETDs)

Cone-rod homeobox: CRX) protein is a "paired-like" homeodomain transcription factor that is essential for regulating rod and cone photoreceptor transcription. Mutations in human CRX are associated with the dominant retinopathies Retinitis Pigmentosa: RP), Cone-Rod Dystrophy: CoRD) and Leber Congenital Amaurosis: LCA), with variable severity. The goal of my dissertation project was to develop and characterize animal models to understand genetic mechanisms of phenotypic diversity in CRX-associated disease. Heterozygous Crx Knock-Out: KO) mice: "+/-") have normal vision as adults and fail to model the dominant human disease.

We generated two Crx Knock-IN: K-IN) mouse models: CrxE168d2: "E168d2") and CrxR90W: "R90W"), which …

Anion-Peptide Adduct Formation And Decomposition As Studied By Fourier Transform Ion Cyclotron Resonance (Ft-Icr) Mass Spectrometry, Xiaohua Liu

University of New Orleans Theses and Dissertations

A new “best match” match model has been developed to account for adduct formation on multiply charged peptides observed in negative ion electrospray mass spectrometry. To obtain a stable adduct, the model necessitates an approximate matching of apparent gas-phase basicity (GBapp) of a given proton bearing site on the peptide with the gas-phase basicity (GB) of the anion attaching at that site. Evidence supporting the model is derived from the fact that singly charged adducts were only observed for lower GB anions: HSO₄^-, I^-, CF₃COO^-. Ions that have medium GBs (NO …

The Effects Of Ecological Context And Individual Characteristics On Stereotyped Displays In Male Anolis Carolinensis, Catherine Policastro

University of New Orleans Theses and Dissertations

Displays are ubiquitous throughout the animal kingdom. While many have been thoroughly documented, the factors affecting the expression of such displays are still not fully understood. We tested the hypotheses that display production would be affected by ecological context (i.e. the identity of the receiver) and intrinsic qualities of the signaler (i.e. heavyweight and lightweight size class) in the green anole lizard, Anolis carolinensis. Our results supported these predictions and show that a) ecological context, specifically displaying to conspecifics, has the greatest impact on display production; b) size class influenced display rate with heavyweight males displaying more to green …

Effects Of Prescribed Burns On Grassland Breeding Birds At Mississippi Sandhill Crane National Wildlife Refuge, Elizabeth A. Ruffman

University of New Orleans Theses and Dissertations

There has been a critical decline in grassland bird populations due to habitat fragmentation and deterioration, and suppression of natural fires. Alteration of the disturbance cycle may lead to changes in vegetation structure and thus habitat suitability for breeding grassland birds. Management practices at the Mississippi Sandhill Crane National Wildlife Refuge, including the use of prescribed fire, are in need of evaluation. My study asked what frequency of prescribed burns is necessary to support breeding grassland birds and whether vegetation structure varies among burn units. In this study, bird abundance and species richness did not differ significantly among burn units …

The Effects Of Chronic Simvastatin Treatment On The Expression Of Behavioral Symptoms In A Transgenic Mouse Model Of Huntington’S Disease, Ashley Whitmarsh

University of New Orleans Theses and Dissertations

Huntington’s disease (HD) is a heritable, neurodegenerative disorder characterized by motor, cognitive, and psychiatric disturbances. An unstable CAG expansion within the gene normally encoding for the Huntingtin protein is responsible. The expanded mutant form of Huntingtin and the putative protein co-factor Rhes interact and cause cell death within the striatum. We hypothesized chronic treatment with simvastatin, a cholesterol lowering drug, would disrupt the biosynthetical pathway which gives both Rhes and its target cells binding sites and render Rhes inactive. Healthy and HD mice were treated with simvastatin or a vehicle. Animals’ motor behavior was assessed with three separate tests over …

Assessing The Responses Of Adult, Juvenile, And Larval Fish Assemblages To The Closure Of The Mississippi River Gulf Outlet, An Artificial Tidal Pass In Southeastern Louisiana, Rebecca Weatherall Cope

University of New Orleans Theses and Dissertations

The creation of the Mississippi River Gulf Outlet (MRGO) in 1963 by the U.S. Army Corps of Engineers (USACE) represents one of the most catastrophic, anthropogenic stressors ever to impact the Lake Pontchartrain estuary in southeastern Louisiana, USA. The artificial tidal pass provided a direct route from the Gulf of Mexico to New Orleans. It allowed for high saline waters to enter Lake Pontchartrain, resulting in detrimental changes to the biotic community of the Lake and surrounding wetland areas. In July 2009, the USACE closed the MRGO in hopes of restoring natural ecosystems. This study assesses changes in the adult, …

Statistical And Comparative Phylogeography Of Mexican Freshwater Taxa In Extreme Aquatic Environments, Lyndon M. Coghill

University of New Orleans Theses and Dissertations

Phylogeography aims to understand the processes that underlie the distribution of genetic variation within and among closely related species. Although the means by which this goal might be achieved differ considerably from those that spawned the field some thirty years ago, the foundation and conceptual breakthroughs made by Avise are nonetheless the same and are as relevant today as they were two decades ago. Namely, patterns of neutral genetic variation among individuals carry the signature of a species’ demographic past, and the spatial and temporal environmental heterogeneity across a species’ geographic range can influence patterns of evolutionary change. Aquatic systems …

Transcriptional Co-Repressor Response Of Arabidopsis Thaliana To Different Abiotic Stress, Bhuwan Guragain

University of New Orleans Theses and Dissertations

Plants adapt to the complex environmental challenges by regulating their gene expression. Analyses of plant genomes have identified many genes that are either expressed or repressed during environmental stress. However we do not have much information on gene repression. Transcriptional repression in Arabidopsis thaliana is caused by co-repressors that lack the DNA binding domain and are recruited by transcription factors to regulate target gene expression. The Sridhar lab has identified co-repressors SLK1, SLK2, and LUH, which prevent the expression of stress response genes under non-stress conditions. Arabidopsis transgenic lines expressing the GUS under the control of co-repressor’s promoter were created, …

Ecology, Phylogenetics, And Conservation Of Draba Asterophora Complex: A Rare, Alpine, Endemic From Lake Tahoe, Usa, Emily Ruth Smith Putnam

Theses and Dissertations

Rare, alpine, endemic species are particularly at risk for extinction. Alpine environments are especially vulnerable to climate change and human impacts, such as ski resort development and snowmaking. Draba asterophora Payson is a rare, alpine species that occurs only in three disjunct mountain-top regions surrounding Lake Tahoe. It is currently threatened by human impacts, such as ski resorts, as well as indirect influences of climate change and therefore in need of better understanding for conservation purposes. Draba asterophora may be able to serve as a case study for other similarly vulnerable, rare, alpine, endemic species with conservation needs. We utilized …

The Diversity Of Quantitative Trait Loci In Yeast Sporulation Efficiency, Kimberly Lorenz

All Theses and Dissertations (ETDs)

A complex trait is one that exhibits continuous phenotypic variation due to genetic variation in many quantitative trait genes: QTGs). The ultimate goal of genetics is to relate genotype to phenotype; in the case of complex traits this requires a better understanding of what types of genes harbor causal natural variation, and what form the variation takes. Here I describe two experiments using the model complex trait of sporulation efficiency in the yeast Saccharomyces cerevisiae, one to specifically investigate how small effects contribute to a quantitative trait and the other to determine whether certain types of genes are more likely …

Molecular And Genetic Analysis Of A Conserved Transcription Factor With A Role In Promoting The Completion Of Cytokinesis In Schizosaccharomyces Pombe, Bidhan Chakraborty

Electronic Thesis and Dissertation Repository

The fission yeast Schizosaccharomyces pombe activates regulatory networks that promote the faithful execution of cytokinesis in response to drugs that perturb the cytokinesis machinery. In order to identify novel components of these networks, a screen for mutants hyper-sensitive to the actin depolymerizing drug LatrunculinA (LatA) was previously performed. This screen identified a transcription factor, Pap1p, which is orthologous to the mammalian stress activated transcription factor, AP-1. Through molecular and genetic analysis, I showed that the deletion mutant of pap1 is sensitive to LatA and that it cannot maintain the integrity of the actomyosin ring upon LatA treatment leading to cytokinesis …

On The Origin Of Phenotypic Variation: Novel Technologies To Dissect Molecular Determinants Of Phenotype, Francesco Vallania

All Theses and Dissertations (ETDs)

This thesis describes the conception, design, and development of novel computational tools, theoretical models, and experimental techniques applied to the dissection of molecular factors underlying phenotypic variation. The first part of my work is focused on finding rare genetic variants in pooled DNA samples, leading to the development of a novel set of algorithms, SNPseeker and SPLINTER, applied to next-generation sequencing data. The second part of my work describes the creation of a reporter system for DNA methylation for the purpose of dissecting the genetic contribution of tissue-specific patterns of DNA methylation across the genome. Finally the last part of …

Post-Fire Interactions Between Soil Water Repellency, Islands Of Fertility, And Bromus Tectorum Invasibility, Kaitlynn Jane Fernelius

Theses and Dissertations

An intrinsic link exists between soil moisture and soil nitrogen. Factors that increase or decrease soil moisture can have a profound effect on soil nitrogen cycling, which may have later repercussions in the plant community. Post-fire soil water repellency is one factor that can limit soil moisture acquisition and may indirectly affect nitrogen cycling and weed invasion in woody islands of fertility. Plots centered on burned Juniperus osteosperma trees were either left untreated or treated with a surfactant to ameliorate water repellency. Two years later, soils were excavated from the untreated and treated field plots. In the greenhouse, half of …

Characterization Of The Alternative Oxidase From The Psychrophilic Green Alga Chlamydomonas Sp. Uwo241, Michael Sj Inman

Electronic Thesis and Dissertation Repository

The alternative oxidase (AOX) was studied in the psychrophilic green alga Chlamydomonas sp. UWO241. AOX is the sole component of the alternative pathway of mitochondrial electron transport and is present in all plant and algal species. In silico analysis of the deduced protein sequence of the cloned AOX cDNA showed that the UWO241 protein has lower amounts of proline and higher amounts of lysine and tryptophan compared to the AOX sequence of the mesophilic alga C. reinhardtii. These changes have been seen in other studies of cold-adapted enzymes. Interestingly, unlike C. reinhardtii, AOX transcript abundance in UWO241 …

Phospholipase D- And Phosphatidic Acid-Mediated Signaling In Plant Response To Abscisic Acid And Reactive Oxygen Species, Liang Guo

Dissertations

The Arabidopsis genome has 12 phospholipase D (PLD) genes that are classified into six types, PLDα, PLDβ, PLDγ, PLDδ, PLDε, and PLDζ, based on sequence similarities, domain structures, and biochemical properties. Phosphatidic acids (PA) produced by PLDs have been identified as important lipid signaling molecules in cell growth, development, and stress responses. This study was undertaken to determine the role of PLD and PA in plant response to abscisic acid (ABA) and reactive oxygen species (ROS). The lipid mediator PA was found to interact with sphingosine kinases (SPHKs) in Arabidopsis. Two unique SPHK cDNAs were cloned and expressed. Both SPHKs …

Environmental Regulation Of Tidal Wetland Microbial Communities And Associated Biogeochemistry, Ember Morrissey

Theses and Dissertations

Microbial communities play an essential role in carrying out the biogeochemical cycles that sustain life on Earth, yet we know very little about their ecology. One question of particular interest is how environmental conditions shape microbial community structure (i.e., the types of organisms found in the community and their relative abundance), and whether such changes in structure are related to biogeochemical function. It is the aim of this dissertation to address this question via the examination of carbon (C) and nitrogen (N) cycling in wetland ecosystems, which due to their diverse hydrology have a profound influence on biogeochemical cycles. With …

Functional Response Of Venus Flytraps (Dionaea Muscipula), Amber D. Martin

Honors Theses

The feeding response of Venus flytraps (Dionaea muscipula) is widely studied, and many studies have considered the selectivity of prey capture in D. muscipula (Lichtner and Williams, 1977; Hutchens and Luken, 2009). The consumption rate of an organism relative to the abundance or availability of its food is known as that organism's functional response (Jeschke et al., 2004). In this study, a functional response curve will be constructed for D. muscipula based on its response to increasing availability of small prey in the laboratory. Knowledge of functional responses is important for various fields of biology including population biology, evolutionary biology, …

Alzheimer's Disease And Circadian Rhythms In A Drosophila Model, Lauren Alejo

Honors Theses

Sleep disorders are commonly reported in Alzheimer's disease, a debilitating, age-related neurodegenerative disorder that affects neurons in the brain. Recently, several studies have suggested a role for sleep abnormalities and the internal "body clock" known as the circadian system, in the disease onset and progression. Since most of the data has been collected from mammals with complex neural circuitry, the molecular and cellular mechanisms that integrate the two neural networks are still limited. This study examined the relationship between circadian rhythmicity and Alzheimer's Disease presentation using a Drosophila model. Flies were crossed using the GAL4-UAS system to display Alzheimer's disease …

Effectiveness Of Gaming Systems On Balance In Older Individuals, Mary E. Anderson

Honors Theses

Balance training using gaming systems, called exergaming, is a rising trend for reducing fall risk in older individuals. Previous studies have conducted research pertaining to gaming systems and traditional balance training, however there is a lack of comparison between gaming systems. This study was performed to determine the effectiveness of two gaming systems, the Wii Fit and Xbox Kinect, as compared to traditional balance training. This study was performed with subjects (N=5) over the age of 65, in good health, randomly placed in one of the three balance training groups: Wii Fit (n=2), Xbox Kinect (n=2), and Traditional balance training …

Prey Capture In Response To Removing Cilia From Venus Flytraps, Emily Marchini

Honors Theses

Carnivorous plants are able to attract, trap, and digest insects. Different types of traps target different prey. There are sticky traps, pitfall traps, and active steel traps (Gibson, 1991). Although this may seem to be a rare modification it appears that there are six origins of carnivorous plants in different groups of angiosperms (Albert et al., 1992). These results indicate that not only were there multiple origins of carnivorous plants, there were also multiple origins of the same trapping mechanism; for example, the flypaper trap has five origins and the pitcher trap has three (Albert et al., 1992). Multiple origins …

Seed Bank Study Of The Effect Of Land Use On Vegetation Diversity In Carolina Bays, Maeve Snyder

Honors Theses

The intent of my honors thesis is to conduct a comparative analysis of seed banks between Carolina bays of high and low human impact. My study will use Geographic Information Systems (GIS) to characterize types of land use within Carolina bays and in 250-m buffer zones. Representative bays from high-impact and low-impact classifications will be chosen as study sites, and seed bank samples will be collected and germinated. While it is beyond the scope of my study to identify a mechanism by which it occurs, I will investigate the presence of a relationship between land use and bay vegetation biodiversity.

The Genetic Architecture And Evolution Of Brain Cortical Folding In A Pedigreed Primate Population, Elizabeth Grace Atkinson

Arts & Sciences Electronic Theses and Dissertations

Elevated neurological faculty, related to the dramatic increase in brain volume, is a hallmark of the primates. Cognitive capacity, the processing power and speed of the brain, is directly related to the number of neurons in the cerebral cortex and the connectivity network underlying information processing in the brain. Increased cortical folding (gyrification) allows for more neurons to be contained within the volume of the braincase and the arrangement of folds and ridges across the cerebral cortex is an indication of the underlying neural network connecting regions. The goal of this dissertation is to develop a better understanding of the …

Prevention Of Increasing Burnout Levels Among Physicians Of Different Specialties And Doctoral Degrees, Taylor Lewis

Honors Theses

Burnout rates are steadily increasing among physicians all over the world (Sime, Quick, Saleh, & Martin, 2007). Burnout is defined as high levels of emotional exhaustion (EE), high levels of depersonalization (DP), and low levels of personal achievement (PA) (Ionita, Copotocan, & Copotoiu, S., 2011). These burnout rates are directly correlated with many factors, such as high levels of emotional exhaustion and stress (McManus, Winder, & Gordon, 2002), little experience in the medical field (Keswani, Taft, Coté, & Keefer, 2011), and long work hours which leads to sleep deprivation and fatigue (Jackson, 1999). These moderate to high levels of burnout …

Cleft Lip And Palate Repair: Bridging The Gap Between Genetics And Oral Health: An Individual Case Study, Duncan Perry

Honors Theses

Cleft Lip and Palate Syndrome (CL/P) is a condition that occurs in vitro, during fetal development. Because the majority of CL/P cases occur in underdeveloped nations, the families of CL/P patients are typically characterized by impoverished homes. These are the very people who cannot afford to pay for folic acid supplements, or reconstructive and reparative surgeries. Many families struggle under the extreme pressure of raising a child with CL/P. In these nations, the child often cannot receive the proper care they need, and usually are the product of unsuccessful surgeries. The stress of a CL/P patient is incredibly high, both …

Characteristics And Effects Of Muscular Dystrophy In Broiler Chickens, Kayla N. Smith

Honors Theses

Muscular dystrophy is very common among broilers, which are chickens raised specifically for meat production. When dystrophic chickens are mated, or when normal and dystrophic chickens are mated, it is very likely that at least fifty percent of the clutch will end up with muscular dystrophy since it is inherited as a co-dominant disorder (Fujiwara et al., 2009). For my study, eggs were obtained from a local farm, and allowed to hatch. Among these hatchings were chicks who exhibited some traits of muscular dystrophy. It is possible that the parents of the seemingly dystrophic chicks may carry the mutated WWP1 …

Sustainable Management Of The Main Two Maltese Indigenous Grape Varieties For Winemaking, Jonathan Falzon

Masters Theses, 2010-2019

Ġellewża and Girgentina, the main two Maltese indigenous grape varieties that are used for winemaking, are grown in small parcels of land with an average size just over 0.1 ha. Policies and regulations that influence the sector have been set up and this increased the need for studies to understand the current management practices and how can they be more sustainable. Through interviews with 30 growers of the indigenous grape varieties it was found that most vines are trained as bush vines and cane pruned with 2 or 3 canes with about 5 to 10 buds in each. Nutrition is …