Biology Commons^™

Tumor-Derived Factors And Reduced P53 Promote Endothelial Cell Centrosome Over-Duplication, Zhixian Yu, Kevin P. Mouillesseaux, Erich J. Kushner, Victoria L. Bautch

Biological Sciences: Faculty Scholarship

Approximately 30% of tumor endothelial cells have over-duplicated (>2) centrosomes, which may contribute to abnormal vessel function and drug resistance. Elevated levels of vascular endothelial growth factor A induce excess centrosomes in endothelial cells, but how other features of the tumor environment affect centrosome over-duplication is not known. To test this, we treated endothelial cells with tumor-derived factors, hypoxia, or reduced p53, and assessed centrosome numbers. We found that hypoxia and elevated levels of bone morphogenetic protein 2, 6 and 7 induced excess centrosomes in endothelial cells through BMPR1A and likely via SMAD signaling. In contrast, inflammatory mediators IL-8 …

Structure, Dynamics, And Regulation Of Collective Cell Migration, Andrew J. Loza

Arts & Sciences Graduate Student Theses and Dissertations

Collective migration is the process by which cells organize individual motions to productively migrate as a group and plays a fundamental role in organism development, tissue regeneration, and cancer invasion. In development, coordinated migration facilitates the formation of complex organ structures and is required for proper dissemination of neural crest cells throughout an organism. After injury, this process allows breaches in epithelial layers to be repaired while maintaining tissue integrity, and in cancer, collective behavior enhances invasion of tumor cells into the surrounding tissue. Chapter 1 provides an introduction for the role of collective migration across an organism’s lifespan, the …

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

Arts & Sciences Graduate Student 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 …

Discovery And Functional Implication Of Genetic Alterations Associated With Clonal Hematopoietic Expansion, Mingchao Xie

Arts & Sciences Graduate Student Theses and Dissertations

Cancers, including hematologic malignancies, arise as a result of the stepwise accumulation of mutations. Some early mutations that potentially initiate clonal expansion might exist in patients many years before they develop obvious disease symptoms. Therefore, identifying and characterizing these early mutations are critical to understanding the genetic basis of tumorigenesis. Here, we analyzed blood-derived DNA sequencing data from 2,728 individuals without apparent hematologic malignancies and identified 77 blood-specific mutations in 31 cancer-associated genes. Importantly, 83% of all mutations occurred in 19 genes that have been previously linked to hematological malignancies, such as DNMT3A, TET2, JAK2, and ASXL1. By investigating these …

The Human Arf Tumor Suppressor Regulates Drosha Nucleolar Localization And Rrna Processing Activity, Sree Chandana Sridhar Yaddanapudi

Arts & Sciences Graduate Student Theses and Dissertations

Ribosomes are vital to the survival of a cell, as they are directly responsible for the synthesis of proteins, which perform critical cellular functions. As such, majority of the energy reserves in a proliferating cell are expended towards synthesis of ribosomes. Cancer cells, with their enhanced proliferation rates, tend to upregulate ribosome biogenesis in order to meet the demand for increased protein synthesis necessary to sustain rapid proliferation. Many of the oncogenes and tumor suppressors known to be deregulated in cancers are capable of positively and negatively regulating ribosome biogenesis, respectively. The ARF tumor suppressor strongly suppresses ribosome biogenesis, particularly …

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 …

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.

Uric Acid Levels In Relation To Progression Of Multiple Sclerosis, Alexander A. Gosch, Mary F. Davis, Joshua C. Denny

Library/Life Sciences Undergraduate Poster Competition 2017

Multiple sclerosis (MS) is a neurodegenerative disease caused by demyelination in the central nervous system. In previous studies, serum uric acid (UA) levels have been implied as a useful biomarker in understanding MS disease progression and development. The majority of previous studies have found MS patients have a lower UA level than healthy controls, however some studies have found higher UA levels with MS patients. Previous studies have compared UA levels between subtypes of MS, but have not produced conclusive data. To better understand the correlation between UA levels and MS patients, we compared UA levels between our set of …

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 …

Effect Of Arginine On Oligomerization And Stability Of N-Acetylglutamate Synthase., N Haskins, A Mumo, P H Brown, Mendel Tuchman, Hiroki Morizono, L Caldovic

Genomics and Precision Medicine Faculty Publications

N-acetylglutamate synthase (NAGS; E.C.2.3.1.1) catalyzes the formation of N-acetylglutamate (NAG) from acetyl coenzyme A and glutamate. In microorganisms and plants, NAG is the first intermediate of the L-arginine biosynthesis; in animals, NAG is an allosteric activator of carbamylphosphate synthetase I and III. In some bacteria bifunctional N-acetylglutamate synthase-kinase (NAGS-K) catalyzes the first two steps of L-arginine biosynthesis. L-arginine inhibits NAGS in bacteria, fungi, and plants and activates NAGS in mammals. L-arginine increased thermal stability of the NAGS-K from Maricaulis maris (MmNAGS-K) while it destabilized the NAGS-K from Xanthomonas campestris (XcNAGS-K). Analytical gel chromatography and ultracentrifugation indicated tetrameric structure of the …

The Study Of The Functions And Regulation Of Mammalian Cap1 (Cyclase-Associated Protein 1), Haitao Zhang

Student Theses and Dissertations

CAP is a conserved actin-binding protein with versatile roles in promoting actin dynamics across species. Mammalian CAPs had been understudied compared to the first identified yeast homologues; their cellular functions remained to be better established. Moreover, CAP function regulation remained a completely uncharted area. Recent studies also implicated CAP in the invasiveness of human cancers. However, some of the evidence was not convincing and further studies were needed. The present study established and identified new cellular functions for mammalian CAP1, identified a regulatory mechanism as phosphorylation at the S307/S309 tandem site along with the cell signals controlling both phosphorylation and …

Patchiness Of Ciliate Communities Sampled At Varying Spatial Scales Along The New England Shelf, Jean-David Grattepanche, George B. Mcmanus, Laura A. Katz

Biological Sciences: Faculty Publications

Although protists (microbial eukaryotes) provide an important link between bacteria and Metazoa in food webs, we do not yet have a clear understanding of the spatial scales on which protist diversity varies. Here, we use a combination of DNA fingerprinting (denaturant gradient gel electrophoresis or DGGE) and high-throughput sequencing (HTS) to assess the ciliate community in the class Spirotrichea at varying scales of 1–3 km sampled in three locations separated by at least 25 km—offshore, midshelf and inshore—along the New England shelf. Analyses of both abundant community (DGGE) and the total community (HTS) members reveal that: 1) ciliate communities are …

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 …

Polypores And Genus Concepts In Phanerochaetaceae (Polyporales, Basidiomycota), Otto Miettinen, Viacheslav Spirin, Josef Vlasák, Bernard Rivoire, Soili Stenroos, David S. Hibbett

Biology

We explored whether DNA-phylogeny-based and morphology-based genus concepts can be reconciled in the basidiomycete family Phanerochaetaceae. Our results show that macromorphology of fruiting bodies and hymenophore construction do not reflect monophyletic groups. However, by integrating micromor-phology and re-defining genera, harmonization of DNA phylogeny and morphological genus concepts is possible in most cases. In the case of one genus (Phlebiopsis), our genetic markers could not resolve genus limits satisfactorily and a clear morphological definition could not be identified. We combine extended species sampling, microscopic studies of fruiting bodies and phylogenetic analyses of ITS, nLSU and rpb1 to revise genus concepts. Three …

Recurring Patterns Among Scrambled Genes In The Encrypted Genome Of The Ciliate Oxytricha Trifallax, Jonathan Burns, Denys Kukushkin, Xiao Chen, Laura F Landweber, Masahico Saito, Nataša Jonoska

Mathematics and Statistics Faculty Publications

Some genera of ciliates, such as Oxytricha and Stylonychia, undergo massive genome reorganization during development and provide model organisms to study DNA rearrangement. A common feature of these ciliates is the presence of two types of nuclei: a germline micronucleus and a transcriptionally-active somatic macronucleus containing over 16,000 gene sized "nano-chromosomes". During conjugation the old parental macronucleus disintegrates and a new macronucleus forms from a copy of the zygotic micronucleus. During this process, macronuclear chromosomes assemble through DNA processing events that delete 90-98% of the DNA content of the micronucleus. This includes the deletion of noncoding DNA segments that interrupt …

A Novel Rrm3 Function In Restricting Dna Replication Via An Orc5-Binding Domain Is Genetically Separable From Rrm3 Function As An Atpase/Helicase In Facilitating Fork Progression, Salahuddin Syed, Claus Desler, Lene J Rasmussen, Kristina H Schmidt

Molecular Biosciences Faculty Publications

In response to replication stress cells activate the intra-S checkpoint, induce DNA repair pathways, increase nucleotide levels, and inhibit origin firing. Here, we report that Rrm3 associates with a subset of replication origins and controls DNA synthesis during replication stress. The N-terminal domain required for control of DNA synthesis maps to residues 186-212 that are also critical for binding Orc5 of the origin recognition complex. Deletion of this domain is lethal to cells lacking the replication checkpoint mediator Mrc1 and leads to mutations upon exposure to the replication stressor hydroxyurea. This novel Rrm3 function is independent of its established role …

Efficient Method For Transfer Of Microinjected Eggs To Mouse Ampulla For Generating Transgenic Mice, Guang Wen, Jin Di, Qian Li, Jianling Chen, Ling Jin, Cheng Wang, Sanqing Xu

Publications and Research

Background: The new method described here is highly efficient in transferring microinjected mouse eggs (MEs) through the bursa membrane of a surrogate mother mouse to the ampulla of the oviduct without damaging the blood vessels on the bursa membrane.

Results: This method causes no loss of blood, and it produces newborn pups/founders from approximately 70% of the transferred MEs, because only a small hole is made on the blood vessel–free area of the bursa membrane and ampulla of the surrogate mother mouse. The infundibulum remains intact. The small hole on the bursa membrane/ ampulla may already heal up before the …

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

Honors Capstones

No abstract provided.

Copper Oxide Nanoparticles Impact Several Toxicological Endpoints And Cause Neurodegeneration In Caenorhabditis Elegans, Michael Joseph Mashock, Tyler Zanon, Anthony D. Kappell, Lisa N. Petrella, Erik C. Andersen, Krassimira R. Hristova

Biological Sciences Faculty Research and Publications

Engineered nanoparticles are becoming increasingly incorporated into technology and consumer products. In 2014, over 300 tons of copper oxide nanoparticles were manufactured in the United States. The increased production of nanoparticles raises concerns regarding the potential introduction into the environment or human exposure. Copper oxide nanoparticles commonly release copper ions into solutions, which contribute to their toxicity. We quantified the inhibitory effects of both copper oxide nanoparticles and copper sulfate on C. elegans toxicological endpoints to elucidate their biological effects. Several toxicological endpoints were analyzed in C. elegans, including nematode reproduction, feeding behavior, and average body length. We examined three …

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. …

Functional Trait Values, Not Trait Plasticity, Drive The Invasiveness Of Rosa Sp. In Response To Light Availability, Rebecca E. Drenovsky, Jennifer E. Murphy

Biology

PREMISE OF THE STUDY : Functional trait plasticity in resource capture traits has been suggested as an underlying mechanism promoting invasive species establishment and spread. Earlier studies on this mechanism treat invasiveness as a discrete characteristic (i.e., invasive vs. noninvasive) and do not consider the potential impacts of evolutionary history. In the present study, we used a continuous measure of invasiveness and a phylogenetic framework to quantify the relationship between functional trait expression, plasticity, and invasiveness in Rosa .

Examining The Combined Effects Of Dissolved Oxygen, Temperature, And Body Size On The Physiological Responses Of A Model Macrobenthic Polychaete Species, Capitella Teleta, Kelsey Burns Gillam

Dissertations

While the scientific community is in consensus that coastal systems are threatened by climate change, few climate change studies test the effects of more than one variable directly related to climate change. The dissolved oxygen (DO) levels of the ocean are currently subject to both global warming and eutrophication; 94% of all hypoxia zones are expected to experience >2°C increase by 2035. This dissertation aims to examine how a model organism responds to simultaneous thermal and DO stress involving four levels of DO (100%, 70%, 50%, and 20%) saturation and three temperatures (15°C, 20°C, and 25°C).

The polychaete, Capitella teleta …

A Microbiomic Approach To The Characterization Of The Impacts And Influences Of Viral, Bacterial, And Harmful Algal Bloom Toxins On The Bottlenose Dolphin, Corey David Russo

Dissertations

As apex predators that display high site fidelity Tursiops truncatus (bottlenose dolphin) are indicators of marine ecosystem health. Bottlenose dolphins, additionally, display pathogenesis and immune response similar to that of humans. Humans and coastal bottlenose dolphins, in particular, are constantly exposed to the same industrial, agricultural and domestic toxins and pathogens, contaminants and pollutants. Thus, studies on the bottlenose dolphin are also valuable in bridging the gap between ocean and human health. Bottlenose dolphins are susceptible to viral bacterial and toxin infection. Infection in the bottlenose dolphin manifests itself in the form of mass stranding events, unusual mortality events, chronic …

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