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Minibrain And Wings Apart Control Organ Growth And Tissue Patterning Through Downregulation Of Capicua, Liu Yang

Graduate Doctoral Dissertations

The regulation of organ growth is a fundamental aspect of developmental biology. My work uses Drosophila as a model system to understand how the various growth regulators are coordinated. The transcriptional repressor Capicua (Cic) controls tissue patterning and restricts organ growth, and has been recently implicated in several cancers and neurodegenerative diseases. Cic has emerged as a primary sensor of signaling downstream of the receptor tyrosine kinase (RTK)/extracellular signal-regulated kinase (ERK) pathway, but how Cic activity is regulated in different cellular contexts remains poorly understood. In order to identify Cic regulators, I have used affinity purification/mass spectrometry (AP-MS) to study …

Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier

Graduate Doctoral Dissertations

The deep sea is the Earth’s largest ecosystem and harbors a unique and largely endemic fauna. Although most research has focused on the ecological mechanisms that allow coexistence, recent studies have begun to investigate how this remarkable fauna evolved.. My work quantifies geographic patterns of genetic variation and investigates potential mechanisms that shape evolution in the deep ocean.

Bathymetric genetic divergence is common in the deep sea with population structure typically decreasing with depth. The evolutionary mechanisms that underlie these patterns are poorly understood. Geographic patterns of genetic variation indicated that the protobranch bivalve Neilonella salicensis was composed of two …

Macroinvertebrate Community Composition, Food Web Structure, And Emergence Rate In Neotropical Cloud-Forest Streams In Mindo, Ecuador, Anna M. Harris

Masters Theses

Tropical cloud forest streams are one of the most threatened and understudied ecosystems in the world. Understanding how these ecosystems function is essential for effective conservation. In this study, macroinvertebrate community composition, functional feeding group analysis, ecosystem attributes, and physicochemical parameters were used to evaluate biophysical stream conditions of 3 low-order Neotropical cloud forest streams at Reserva Las Gralarias in Mindo, Ecuador. Additionally, food web structure was analyzed via stable isotope analysis and aquatic insect emergence rate was also examined. As stream size increased from 1st to 3rd order, the macroinvertebrate communities shifted from being collector-gatherer dominated (65.2 to 29.8%, …

Mitigating The Impacts Of Human Land-Use Change On Biodiversity: With A Focus On Large Migratory Herbivores, Kina Rebekah Murphy

Biology ETDs

Land-use change, commercial over-harvesting of species, and climate change are recognized as the main drivers of biodiversity loss. As a result, it is estimated that 30% of the planet’s biodiversity may go extinct by 2050. This dissertation focuses on how to mitigate the impacts of land-use change on biodiversity. I focus on large migratory herbivores because they are among the most heavily impacted by global change due to their large home range requirements. Habitat fragmentation, illegal hunting, and human-wildlife conflicts are among the biggest threats to large herbivores and result from land-use change. For this reason, my first chapter focuses …

Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski

Biology Theses

Habitat suitability modeling using the software package MaxEnt (Phillips, Anderson, & Schapire, 2006) is a popular method for describing the habitat of rare species. MaxEnt uses “presence only” data to develop models; however presence data are highly skewed towards areas of high detection probability and these areas may not represent the full range of habitat use. Thusly, predictions from models developed using only data from areas with high detection probability may not represent all suitable habitat. This study tested the ability of MaxEnt models developed using three different data sets to accurately describe Western Massasauga (Sistrurus t. tergeminus) habitat at …

The Role Of Diaphanous In Ring Canal Development In Drosophila Melanogaster, Alexandra M. Kindred

Undergraduate Honors Thesis Collection

Infertility is a widespread condition that does not always have a known cause, and for which we often do not have a cure. One potential cause of infertility is defects in gametogenesis, or the formation of sperm and egg. During gametogenesis in most organisms, the developing sperm and egg are connected to each other or to supporting cells through intercellular bridges, allowing transfer of materials between cells. Defects in these connections can lead to infertility. The developing fruit fly egg is an excellent model system to study intercellular bridges, or ring canals. Rich in f-actin and actinbinding proteins, ring canals …

Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos

Electronic Theses and Dissertations

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method …

The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai

Electronic Thesis and Dissertation Repository

Galectins are a group of β-galactoside-binding proteins involved in different cellular processes including stress responses and differentiation. The role and expression of galectins under oxidative stress and during neutrophilic differentiation was examined in HL-60 cells. Galectin gene (LGALS), and galectin protein expression were determined using RT-qPCR and immunoblotting, respectively. Neutrophilic differentiation was measured via a spectrofluorometric assay. DNA methylation and JNK signaling were investigated as galectin regulatory mechanisms. Menadione-induced oxidative stress, DMSO-induced differentiation, DNA hypomethylation and JNK signaling all promoted similar galectin expression profiles. Antioxidant N-acetylcysteine attenuated the menadione-induced galectin expression but only partially attenuated DMSO-induced galectin expression. …

Discovery And Characterization Of A Novel Class Of Metabolic Regulators In The Malaria Parasite Plasmodium Falciparum, Ann Marie Guggisberg

Arts & Sciences Electronic Theses and Dissertations

The malaria parasite, Plasmodium falciparum, infects hundreds of millions of people per year and causes hundreds of thousands of deaths. Within the host red blood cell, the parasite relies on glycolysis for energy and synthesis of essential biomolecules. One such anabolic fate of glucose is the synthesis of isoprenoids, a broad and essential class of compounds that participate in a variety of cellular functions. In the face of ever-evolving drug resistance, new inhibitors and better understanding of parasite metabolism are required. The antibiotic fosmidomycin (FSM) targets the methylerythritol phosphate pathway for isoprenoid synthesis and is a well-validated inhibitor of P. …

Biogeography, Interspecific Introgression, And The Evolution Of Hemoglobin Genes In The High Andes: The Evolutionary History Of The South American Siskins (Spinus), Elizabeth Jane Beckman

Biology ETDs

Landscape features, interspecific introgression, and adaptation work in concert to shape the evolutionary history of a clade. Understanding the independent and cumulative consequences of these evolutionary processes on diversification is critical to revealing the origins of extant biodiversity. Studying these processes within rapid radiations, a significant contributor to global biodiversity, can provide powerful insight into the process of diversification. To assess how diversification is shaped by these evolutionary forces, I examined the biogeographic history, patterns of interspecific introgression and adaptation to high elevation in a recent, rapid radiation of finches, the South American siskins (Fringillidae: Spinus). I found that …

Genetic Mechanisms For The Maintenance Of Behavioral Mating Barriers In Drosophila, Kathleen M. Mortland

Arts & Sciences Electronic Theses and Dissertations

One of the most successful and diverse systems involved in the maintenance of behavioral barriers between closely related animal species is pheromonal communication. In the fruit fly, contact chemosensation input is especially important during sexual decision-making as it allows for the sensing of sex and species-specific non-volatile cuticular hydrocarbons (CHCs), which function as insect pheromones. However, how pheromonal systems support the maintenance of mating barriers is puzzling since any change in either pheromone ligands or their cognate receptors would carry a fitness cost, which should be eliminated by stabilizing selection. To resolve this evolutionary conundrum I hypothesized that pleiotropic genes …

Epigenomics Of Cell Fate In Development And Disease, Rebecca Faith Lowdon

Arts & Sciences Electronic Theses and Dissertations

Epigenetic features at regulatory elements provide instructive cues for transcriptional regulation during development. However, the particular epigenetic alterations necessary for proper cell fate acquisition and differentiation are not well understood. This dissertation explores the epigenetic dynamics of regulatory elements during development and uses epigenome annotations to document inappropriate transcriptional regulation in disease. First, I summarize my contributions to developing a new algorithm for detecting differential DNA methylation, M&M. I report the application of the M&M algorithm to identify distinct classes of DNA methylation dynamics in surface ectoderm (SE) progenitor cells and SE-derived lineages: epigenome alterations, and differential DNA methylation in …

Salvinia Molesta: An Assessment Of The Effects And Methods Of Eradication, Arti Lal

Master's Projects and Capstones

Salvinia molesta is an invasive aquatic fern. It is now the second worse aquatic invader in the world. Since the 1930s, it has invaded most tropical and some temperate countries. S. molesta plants grow vegetatively and can increase in size rapidly. S. molesta can form thick mats of up to 1-meter-thick. There are a number of ways these thick mats negatively affect the environment: 1) reduce light to benthic organisms, 2) reduce oxygen in the water column for other organisms, 3) accumulate as organic matter at the bottom of the water column, 4) decrease nutrients for other organisms, and 5) …

Anthropogenic Disturbance Modulates Mammal Community Diversity, Assembly, & Abundance: Emerging Infectious Disease Risk In The Greater Yellowstone Ecosystem, Leticia Andrea Gutiérrez Jiménez

Dissertations

This dissertation examines the role of mammalian biodiversity in maintaining overall ecosystem health in the Greater Yellowstone Ecosystem (GYE). The study explores the pathways by which anthropogenic disturbance prevents or promotes the emergence of human infectious diseases. I studied two paramount research questions: Question 1: What are the direct effects of anthropogenic disturbance on rodent community assemblages and the consequent indirect effects on public health? I first surveyed the GYE rodent community and their pathogens by using land use as a measure of anthropogenic disturbance (e.g., human settlements, horseback ranches, pastures, undisturbed). I identified pathogens in rodent blood samples by …

Synthetic Ion Channels: A New Class Of Membrane Disruptor And Efflux Pump Inhibitor For The Recovery Of Antibiotic Potency, Mohit Bharatkumar Patel

Dissertations

Antibiotic resistance has become a world-wide health care crisis. In 2013 there were 50,000 deaths in U.S. and EU, associated with hospital acquired bacterial infections. This problem is exacerbated by the lack of new antibiotics in development. Here, we report that synthetic amphiphiles represent a new class of adjuvants that rescue antibiotic potency against multidrug resistant bacteria. Hydraphiles are amphiphiles, designed and synthesized in Gokel lab, that show many of the same properties as protein ion channels. Hydraphiles were previously shown to have antimicrobial activity against Escherichia coli, Bacillus subtilis and Saccharomyces cerevisiae. Here, we report that hydraphiles recover the …

Endogenous Small Interfering Rna: Insights Into Esirna Biogenesis And Their Precursors, Andrew White Harrington

Dissertations

Rarely in research is the path to an answer straightforward. Initial questions lead to more questions, many times doubling back to allow for greater insight into the original question. For example, discovery of interactions between previously unrelated pathways can lead to breakthroughs with regard to understanding of gene regulation. One such novel interaction and the subsequent discoveries this interaction spurred are discussed herein. Transposons, or “Jumping Genes” are mobile genetic elements found throughout all three major domains of life. Transposons comprise 44% of the human genome and possess the ability to move within the genome. This ability makes them an …

Color-Mediated Foraging By Pollinators: A Comparative Study Of Two Passionflower Butterflies At Lantana Camara, Gyanpriya Maharaj

Dissertations

Colorful floral signaling and resulting insect foraging behaviors have only been extensively examined in hymenopteran pollinators, especially bees, in comparison to flies, beetles, and butterflies regardless of their ecological importance. Therefore, my study provides novel information by focusing on foraging behaviors of adult passionflower butterflies, Heliconius melpomene and Dryas iulia, to the color changing flowers of Lantana camara. My dissertation which is divided into four chapters, aims to explore various aspects of color mediate foraging in passionflower butterflies by combining observations in the wild with controlled field and laboratory experiments. In the first chapter I reviewed flower color development and …

Genomic Description And Annotation Of A New Colivirus; Kb1, Maggie Caswell

Honors Projects

KB1 is a bacteriophage with relatively few established characteristics. However, it is thought to be similar to the novel environmental isolate bacteriophage, JK5. The aim of this study was to describe and annotate the genome of this new colivirus, relative to the genome of JK5. This comparison confirms the hypothesis that these are similar, but distinct viruses, and provides a foundation for the further understanding of both of these novel environmental isolates.

Historical Biogeography, Spatial Distribution, And Within-Host Interactions Of Avian Haemosporidian Parasites (Apicomplexa, Haemosporida), Leticia De Souza Soares

Dissertations

This dissertation addresses several aspects of the biogeography and evolution of avian malarial parasites (Haemosporida: Plasmodium and Haemoproteus), and the interactions of these pathogens with their hosts and other avian blood parasites. In Chapter 1, I investigate change in haemosporidian assemblages on the West Indies over millennial time scales, taking advantage of the historical isolation of islands by postglacial rising sea levels. I found that, the prevalence of parasite lineages is highly dynamic over periods from decades to thousands of years. Turnover of lineages requires more time than variation in lineage prevalence, suggesting that competitive exclusion of parasite lineages, likely …

The Effect Of Wee1 On Mitosis In The Spb Mutant, David Leroy

Honors Theses

The speedbump mutant has been identified as an early arrest mutant, becoming apparent as soon as 80% epiboly (8.5 hours of development). This mutant has a mutation in wee1, which is a protein regulating entry into mitosis ensuring the completion of DNA replication before mitosis. The lack of this protein in speedbump allows for early entry into mitosis resulting in damage to the chromosome. Here, we investigate two questions: if mitosis in the speedbump mutant phenotype is more frequent than wild-type phenotype, and, if so, is there a phase in which the mutant phenotype favors. We used phosphorylated histone H3 …

Effects Of Gut-Associated Yeasts On Drosophila Melanogaster Performance, Yanira Jiménez Padilla

Electronic Thesis and Dissertation Repository

I used Drosophila melanogaster as a model to study the role of the gut microbiota, specifically yeasts, in animal physiology. I used Saccharomyces cerevisiae, the yeast commonly included in Drosophila diet, and Lachancea kluyveri, isolated from some Drosophila in the wild, and generated axenic (germ-free) and gnotobiotic (yeast-fed) flies. I found that L. kluyveri persists in the crop, as ascospores and vegetative cells, longer than S. cerevisiae. Some L. kluyveri vegetative cells survive passage through the gut. Egg to adult development time is reduced by 14% in vials containing live L. kluyveri or S. cerevisiae, whereas …

Weight Management Delivered Through An App, May Help Resolve Body Image Dissatisfaction In Women Enrolled In Wic, Alexis Ariel O’Connell

Honors Theses

No abstract provided.

An Analysis Of Morphometric Differentiation In Lake And River Populations Of The Emerald Shiner, Notropis Atherinoides, John J.V. Lang

Biology Theses

Understanding mechanisms that account for phenotypic variation has been of interest to biologists since the advent of Darwin’s theory of evolution by natural selection. It is now understood that adaptive divergence is a key driving force of intraspecific differentiation. Further, differences in habitat (e.g., flow regime, prey regime) have been shown to drive adaptive divergence in fish. For instance, fish inhabiting faster flowing water generally exhibit more fusiform bodies than their lake counterparts. Similarly, the partitioning of benthic and pelagic morphs generally results in smaller heads with the latter. This study used geometric shape analysis to assess morphological differences between …

Understanding The Historical Diversification Of Valerianacea, Taylor Lebourgeois

Senior Honors Theses

Ecologists and evolutionary biologists have long recognized that species diversity is unequally distributed among angiosperm lineages. For example, various plant clades found in the Andes have been proposed as examples of rapid radiations, and the Andes are recognized as one of the Earth’s biodiversity “hotspots”. Species within Valerianaceae, found in the South American Andes, appear to be an example of such a rapid radiation. Although much attention has been paid to the phylogeny of the South American species of Valerianaceae, there is still a great deal of uncertainty regarding species relationships. Several subgroups within the Andean Valerians have, either not …

Preliminary Examination Of The Bacterial Diversity Harbored By The Pill Bug (Armadillidium Vulgare), Sondos Alhajouj

Theses & Dissertations

Pill bugs (Armadillidium vulgare) were examined at 4 time points during 2015- 2016. The time points corresponded to summer, fall, winter, and spring. At each time point, 2 to 10 pill bugs were collected from each of three sites. All sites were located in San Antonio, Texas. The first site was in central San Antonio, but due to difficulties in collecting specimens the first site was only utilized at the first time point. The remaining localities, Bonilla Science Hall on the campus of the University of the Incarnate Word and a private residence in northwest San Antonio, were …

The Effect Of Varying Environmental Conditions On The Growth Of Stenotrophomonas Maltophilia, Norah Alqahtani

Theses & Dissertations

Stenotrophomonas maltophilia has emerged as an important opportunistic pathogen in the debilitated host. It possesses the ability to target and colonize respiratory-tract epithelial cells and grow on the surface of medical devices. It is associated with a significant case-fatality ratio in cystic fibrosis patients. S. maltophilia species have the ability to grow in bacterial biofilms, which further complicates these infections by providing the opportunity for acquisition of antibiotic resistant genes. This study investigated the effects on the growth of different strains of the same species of S. maltophilia, ATCC 51331 and 13637, when the selected environmental factors are varied. …

Determining The Impacts Of Environmental Contaminants To Zebra Mussels Using Genetic Biomarkers, Nicklaus James Neureuther

Theses and Dissertations

ABSTRACT

DETERMINING THE IMPACTS OF ENVIRONMENTAL CONTAMINANTS TO ZEBRA MUSSELS USING GENETIC BIOMARKERS

by

Nicklaus James Neureuther

The University of Wisconsin-Milwaukee, 2016

Under the Supervision of Professor Rebecca Klaper, PhD

Persistent legacy contaminants and emerging chemicals of concern continue to be a threat to the function and health in the Great Lakes Areas of Concern (AOCs). While chemical monitoring programs traditionally sample water and sediment, these studies can only provide information of the type and level of contamination within an (AOC). This being said, information on the biological impacts to the biota are needed to measure impairments of chemical exposure, …

Functional And Structural Characterization Of The Mevalonate Diphosphate Decarboxylase And The Isopentenyl Diphosphate Isomerase From Enterococcus Faecalis, Chun-Liang Chen

Open Access Dissertations

Enterococcus faecalis causes a diverse range of nosocomial infections (in wounds, the gastrointestinal tract, the blood stream and the endocardium), and multidrug-resistant strains have become a serious issue across countries. Vancomycin, a FDA-approved drug for the disruption of the bacterial cell wall biosynthesis, has been utilized to treat infectious diseases caused by Enterococci; however, the prevalence of vancomycin-resistant enterococci (VRE) threatens communities all over the world. We aim at developing novel therapeutic strategies to control bacterial growth of Enterococci, and we focus on targeting two essential enzymes involved in poly-isoprenoid biosynthesis in Enterococcus faecalis; one is the mevalonate diphosphate decarboxylase …

Ros Regulation Of Axonal Mitochondrial Transport, Pin-Chao Liao

Open Access Dissertations

Mitochondria perform critical functions including aerobic ATP production and calcium (Ca2+) homeostasis, but are also a major source of reactive oxygen species (ROS) production. To maintain cellular function and survival in neurons, mitochondria are transported along axons, and accumulate in regions with high demand for their functions. Oxidative stress and abnormal mitochondrial axonal transport are associated with neurodegenerative disorders. However, we know little about the connection between these two. Using primaryDrosophila neuronal cell culture and the third instar larval nervous system as in vitro and in vivo models, respectively, we studied mitochondrial transport under oxidative stress conditions. In vitro …

The Role Of Seed Attributes In Eastern Gray Squirrel Foraging, Mekala Sundaram

Open Access Dissertations

Seed attributes are important predictors of rodent foraging behaviors. I examined the role of seed attributes in eastern gray squirrel (Sciurus carolinensis) foraging behavior from an evolutionary, economic, ecological and biochemical perspective. From an evolutionary perspective (chapter 2), I found that squirrel foraging behaviors are influenced by a combination of phylogenetically conserved and evolutionarily labile seed traits, which supports a diffuse coevolutionary relationship between hardwood trees and squirrels and provides indirect evidence supporting the Janzen-Connell and handling time hypotheses. From an economic perspective (chapter 3), I found that eastern gray squirrels are homogenous with respect to their preferences for seed …