Life Sciences Commons^™

Distribution, Abundance, And Population Genetics Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Mississippi, Luke Pearson

Dissertations

The southeastern United States is a freshwater turtle biodiversity hotspot, second only to southeastern Asia, and this region is inhabited by one of the largest freshwater turtles in the world: the alligator snapping turtle (Macrochelys temminckii). This species was heavily harvested from the 1960’s to the 1980’s for the turtle soup industry, apparently contributing to substantial, range-wide population declines. These declines, coupled with anthropogenic impacts on riverine and floodplain habitats, have led to M. temminckii being petitioned for federal listing under the U.S. Endangered Species Act; it is currently under review by the U.S. Fish and Wildlife Service …

Climate And Agronomy, Not Genetics, Underpin Recent Maize Yield Gains In Favorable Environments, Gonzalo Rizzo, Juan Pablo Monzon, Fatima Amor Tenorio, Réka Howard, Kenneth G. Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Quantitative understanding of factors driving yield increases of major food crops is essential for effective prioritization of research and development. Yet previous estimates had limitations in distinguishing among contributing factors such as changing climate and new agronomic and genetic technologies. Here, we distinguished the separate contribution of these factors to yield advance using an extensive database collected from the largest irrigated maize-production domain in the world located in Nebraska (United States) during the 2005-to-2018 period. We found that 48% of the yield gain was associated with a decadal climate trend, 39% with agronomic improvements, and, by difference, only 13% with …

Divergent Selection For Water Conversion Ratio In Broiler Populations, Joseph Hiltz

Graduate Theses and Dissertations

Water scarcity is a global reality and with the anticipated population growth, freshwater resources will be further strained to meet both human needs and agriculture applications. To ensure a water sustainable and food secure future, all aspects of agriculture must become more efficient. Two strategies were explored. The potential of improving water efficiency in broilers was examined. The first strategy was to develop a more efficient and accurate method for measuring water consumption/inputs in agriculture. To date, water measuring technology has lacked the necessary sophistication to assure accuracy and repeatability of low flow water usage.

After establishing a low flow …

Mutant Kras Alters Extracellular Vesicle Microrna Sorting In Pancreatic Cystic Neoplasms, Rachel L. Dittmar

Dissertations & Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers by organ site with a 5-year survival rate of just 10.8%. This is largely because most patients do not experience symptoms until the disease has already metastasized. The best hope to cure PDAC is surgery, which can only be done with a curative intent at an early stage when the disease is localized. There are no reliable circulating, body-fluid-based biomarkers to detect early stage PDAC or its precursor lesions in a timely manner for effective surgical intervention. When potential PDAC precursor lesions, such as mucinous pancreatic cysts are found, there are …

Achievements And Perspectives In The Breeding Of Tropical Grasses And Legumes, John W. Miles

IGC Proceedings (1997-2023)

Pasture and forage plant breeding is complicated by the perennial nature of the plants, the diversity of environments in which improved cultivars will be used, and the complex criteria of merit involved, criteria that necessarily include some measure of impact on the efficiency of animal production. While pasture plant breeding in the temperate zone is a demonstrably productive activity, the record of success for the tropical species -- "success" measured by release and adoption of bred cultivars -- is less convincing, in spite of four decades of activity in numerous public sector breeding programs and a large published literature. The …

Alfalfa, J. H. Bouton

IGC Proceedings (1997-2023)

Cultivated alfalfa or lucerne (Medicago sativa spp. sativa) is the most important forage legume in the world with approximately 32 million hectares cultivated mainly in the temperate regions of both the northern and southern hemispheres. Intensive research has been conducted on the management and physiology of the crop and a major seed industry has developed world wide. Since insect and disease pests are numerous in alfalfa, development of cultivars with the proper fall dormancy and a broad genetic base for pest resistance has been pursued in order to provide increased adaptation, persistence, and yield. There has been a …

Editorial For The Genetics Of Alzheimer’S Disease Special Issue: October 2021, Laura Ibanez, Justin B. Miller

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

Invasion Genetics Of The Non-Native Geckos Phelsuma Grandis Gray 1870 And Gekko Gecko (Linnaeus 1758) In Southern Florida, Usa, Thomas William Fieldsend

FIU Electronic Theses and Dissertations

Biological invasions cause tremendous damage to ecosystems, economies, and human livelihoods worldwide. Florida is home to more established non-native species of reptiles and amphibians than anywhere else on Earth, many of which cause substantial harm to native biodiversity and human well-being. The relatively new discipline of invasion genetics promises to significantly improve the understanding, prediction, prevention, and management of biological invasions. The purpose of this dissertation is to utilize invasion genetics techniques to further understanding of the patterns and processes of biological invasions, especially as they pertain to Florida’s destructive and diverse non-native squamate reptile assemblage. In the first phase …

Population Genetic Analyses Of Arctic Char (Salvelinus Alpinus) Life History Types In Nettilling Lake & Amadjuak River Ecosystem: A Test Of Reproductive Isolation, Chen Liu

Electronic Theses and Dissertations

A great number of studies have identified strong genetic differences between sympatric anadromous and resident populations of Salmonidae. However, Arctic char (Salvelinus alpinus) migratory phenotypes in the Nettilling Lake and Amadjuak River ecosystem in Nunavut, Canada have not been genetically characterized, and it remains unclear if distinct genotypes and phenotypes associated with migratory life history differences are maintained through reproductive isolation, and they have been assumed to be sympatric populations, or co-occurring populations. Co-occurring Arctic char (n=225) were sampled from eleven sites along the Amadjuak River in 2014 and 2015. Twelve microsatellite loci were used to quantify genetic variation among …

The Effects Of Ppal-1 In Arabidopsis Gamete Development, Amanda J White, Susana Perez-Martinez, Mark P. Running

The Cardinal Edge

Prenylation is a type of post-translational modification in which a 15- or 20-carbon lipid is added to the carboxyl (C) terminus of the protein. Arabidopsis thaliana contains the PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) gene, which encodes a protein with homology to the α-subunits of the three known prenylation enzymes, PFT, PGGT, and Rab-GGT. We previously identified two mutations in PPAL, one of which is ppal-1, which contains a T-DNA insertion in the fourth intron. We have previously observed that self-fertilizing heterozygous ppal-1 plants produce progeny in which homozygous ppal-1 is underrepresented. This project attempts to ascertain …

The Onset Of Exercise-Associated Hyponatremia And Individual Differences In Inappropriate Arginine Vasopressin Excretion: A Review Of Proposed Mechanisms, Michelle Stehman, Stephen A. Maris

Topics in Exercise Science and Kinesiology

Topics in Exercise Science and Kinesiology Volume 2: Issue 1, Article 10, 2021. Exercise-associated hyponatremia (EAH) has been reported to develop during endurance events such as triathlons and marathons. As these events become more popular, the incidence of developing EAH also increases. The development of EAH is commonly associated with the overconsumption of hypotonic fluids such as water and tends to be more prevalent in females. There is also evidence to suggest the inappropriate secretion of arginine vasopressin (AVP) leading to water retention may predispose an individual for developing EAH, especially when coupled with the overconsumption of fluids. Recent research …

Phylogenomics And Population History Of Cichlid And Live-Bearing Fish Species In Lowland Neotropical Rivers, Konrad Taube

College of Science and Health Theses and Dissertations

Within Middle America, cichlids and poeciliids account for more than half of the fish biodiversity. This richness in fish fauna highlights the complexity of Middle American biogeography: no other continental area on earth contains within its range the unparalleled abundance of secondary freshwater fish species (fish that can tolerate both saltwater and freshwater). Research into the biogeography of widely distributed Middle American freshwater fish is essential to understanding this unique region.

Three species of freshwater fishes (Belonesox belizanus – Pike killifish, Vieja maculicauda – Black belt cichlid, and Gambusia nicaraguensis – Nicaraguan mosquitofish) are widely distributed across rivers on …

Meat Tenderness: Advances In Biology, Biochemistry, Molecular Mechanisms And New Technologies, Robyn D. Warner, Tommy L. Wheeler, Minh Ha, Xin Li, Alaa El-Din Bekhit, James Morton, Rozita Vaskoska, Frank R. Dunshea, Rui Lui, Peter Purslow, Wangang Zhang

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Meat tenderness is an important quality trait critical to consumer acceptance, and determines satisfaction, repeat purchase and willingness-to-pay premium prices. Recent advances in tenderness research from a variety of perspectives are presented. Our understanding of molecular factors influencing tenderization are discussed in relation to glycolysis, calcium release, protease activation, apoptosis and heat shock proteins, the use of proteomic analysis for monitoring changes, proteomic biomarkers and oxidative/nitrosative stress. Each of these structural, metabolic and molecular determinants of meat tenderness are then discussed in greater detail in relation to animal variation, postmortem influences, and changes during cooking, with a focus on recent …

A Timeline Of Discovery And Current Research On Primary Open-Angle Glaucoma And Emergence Of Potentially Permanent Treatment Solutions, Yonosuke Dejesus, Guadalupe Moreno Ceballos

Spectra Undergraduate Research Journal

This research examines the timeline of the discovery and research of Primary Open-Angle Glaucoma (POAG). By reviewing the literature on genetic and molecular mechanisms, we aim to emphasize a long-term treatment solution (iSTENT) to mitigate intraocular pressure (IOP) related to POAG etiology and disease progression. POAG is a multifactorial, autosomal dominant, adult-onset eye disease wherein the optic nerve cells become damaged due to a buildup of excess aqueous humor, resulting in increased IOP. Consequently, POAG leads to progressive loss of peripheral vision and is the leading cause of blindness in the US. Due to the multifactorial nature of glaucoma’s inheritance …

You Are What You Eat — Exploring The Microbiome Through Inquiry-Based Labs. Microbiome Lesson Plans, Karla S. Fuller

Open Educational Resources

If these commonly used spices have the ability to inhibit pathogenic bacterial growth, could they also potentially inhibit the growth of normal, harmless bacteria that live in your body? In this lab, we will test common bacteria for resistance to food additives.

The Ovarian Follicle Of Ruminants: The Path From Conceptus To Adult, Jennifer L. Juengel, Robert A. Cushman, Joëlle Dupont, Stéphane Fabre, Richard G. Lea, Graeme B. Martin, Francesca Mossa, Janet L. Pitman, Christopher A. Price, Peter Smith

Roman L. Hruska U.S. Meat Animal Research Center: Reports

This review resulted from an international workshop and presents a consensus view of critical advances over the past decade in our understanding of follicle function in ruminants. The major concepts covered include: (1) the value of major genes; (2) the dynamics of fetal ovarian development and its sensitivity to nutritional and environmental influences; (3) the concept of an ovarian follicle reserve, aligned with the rise of anti-Müllerian hormone as a controller of ovarian processes; (4) renewed recognition of the diverse and important roles of theca cells; (5) the importance of follicular fluid as a microenvironment that determines oocyte quality; (6) …

B.R. Wells Arkansas Rice Research Studies 2020, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 47.5% of total U.S. rice production and 48.1% of the total acres planted to rice in 2020. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …

Genetic Approaches For The Study Of Complex Human Diseases, Julieta Lazarte

Electronic Thesis and Dissertation Repository

The field of human genetics has evolved from its initial narrow focus on single-gene Mendelian disorders, which largely affect children, to our current understanding that for most diseases there is continuum of rare to common variants which can exert a range of phenotypic effects. Despite advances in sequencing capabilities and our overall understanding of diseases, there remains a large proportion of heritability unexplained. Through the use of next-generation sequencing technologies and DNA microarray, I have explored a spectrum of genetic variations from rare, single and structural variants to common variants in individuals with i) “lone” atrial fibrillation; ii) familial hypercholesterolemia; …

Population Structure Associated With Bioregion And Seasonal Prey Distribution For Indo‐Pacific Bottlenose Dolphins (Tursiops Aduncus) In South Africa, O. Alejandra Vargas‐Fonseca, Paige Yates, Stephan P. Kirkman, Pierre A. Pistorius, Daniel M. Moore, Ada Natoli, Victor Cockcroft, A. Rus Hoelzel

All Works

Many marine species exhibit fine‐scale population structure despite high mobility and a lack of physical barriers to dispersal, but the evolutionary drivers of differentiation in these systems are generally poorly understood. Here we investigate the potential role of habitat transitions and seasonal prey distributions on the evolution of population structure in the Indo‐Pacific bottlenose dolphin, Tursiops aduncus, off South Africa’s coast, using double‐digest Restriction‐site Associated DNA sequencing (ddRADseq). Population structure was identified between the eastern and southern coasts and correlated with the habitat transition between the temperate Agulhas (southern) and subtropical Natal (eastern) Bioregions, suggesting differentiation driven by resource specialisations. …

The Role Of Interspecies Recombination In The Evolution Of Antibiotic-Resistant Pneumococci, Joshua C. D'Aeth, Mark Pg Van Der Linden, Lesley Mcgee, Herminia De Lencastre, Paul Turner, Jae-Hoon Song, Stephanie W. Lo, Rebecca A. Gladstone, Gps Consortium, Sadia Shakoor

Department of Pathology and Laboratory Medicine

Multidrug-resistant Streptococcus pneumoniae emerge through the modification of core genome loci by interspecies homologous recombinations, and acquisition of gene cassettes. Both occurred in the otherwise contrasting histories of the antibiotic-resistant S. pneumoniae lineages PMEN3 and PMEN9. A single PMEN3 clade spread globally, evading vaccine-induced immunity through frequent serotype switching, whereas locally circulating PMEN9 clades independently gained resistance. Both lineages repeatedly integrated Tn916-type and Tn1207.1-type elements, conferring tetracycline and macrolide resistance, respectively, through homologous recombination importing sequences originating in other species. A species-wide dataset found over 100 instances of such interspecific acquisitions of resistance cassettes and flanking …

Profiling Variable-Number Tandem Repeat Variation Across Populations Using Repeat-Pangenome Graphs., Tsung-Yu Lu, Human Genome Structural Variation Consortium, Mark J P Chaisson, Charles Lee, Qihui Zhu

Faculty Research 2021

Variable number tandem repeats (VNTRs) are composed of consecutive repetitive DNA with hypervariable repeat count and composition. They include protein coding sequences and associations with clinical disorders. It has been difficult to incorporate VNTR analysis in disease studies that use short-read sequencing because the traditional approach of mapping to the human reference is less effective for repetitive and divergent sequences. In this work, we solve VNTR mapping for short reads with a repeat-pangenome graph (RPGG), a data structure that encodes both the population diversity and repeat structure of VNTR loci from multiple haplotype-resolved assemblies. We develop software to build a …

Genetic Resistance To The Downy Mildew Pathogen And Breeding Towards Durable Disease Management In Spinach, Bazgha Zia

Graduate Theses and Dissertations

Spinach (Spinacia oleracea) is a self-pollinated, dioecious winter crop. Prevalent challenges to the production of spinach include disease pressure imposed by downy mildew, which is caused by Peronospora effusa (=P. farinosa f. sp. spinaciae [Pfs]). A total of 19 new races of P. effusa have emerged, imposing serious challenges to the disease management in spinach production. Accordingly, this study was designed to explore the genetic components for establishing the basis of durable disease resistance development against the downy mildew pathogen (P. effusa 13) in spinach, through the use of various genome engineering approaches.

Our results have led (Chapter 2) to …

The Role Of Single Nucleotide Polymorphisms Causing A Dysregulation Of The Hpa Axis On The Incidence Of Depression, Elsa Bechu, Brian Cohen

Honors Theses

Depression is one of the most prevalent diseases worldwide, afflicting approximately 17 million adults in the US in 2019. A prominent causal factor of depression is dysregulation of our body’s response to stress when exposed to continuous stressors over long periods of time. Stress is regulated by the Hypothalamic-Pituitary-Adrenal (HPA) axis, with cortisol as its effector hormone. The effects of cortisol are exerted through the glucocorticoid and mineralocorticoid receptors (GR and MR, respectively) in the body and the brain, respectively. The HPA axis is regulated by a negative feedback loop where activation of the GR by circulating cortisol inhibits the …

Identifying The Cell Composition And Clonal Diversity Of Supratentorial Ependymoma Using Single Cell Rna-Sequencing, James He

University Scholar Projects

Ependymoma is a primary solid tumor of the central nervous system. Supratentorial ependymoma (ST-EPN), a subtype of ependymomas, is driven by an oncogenic fusion between the ZFTA and RELA genes in 70% of cases. We introduced this fusion into neural progenitor cells of mice embryos via in utero electroporation of a non-viral binary piggyBac transposon system containing ZFTA-RELA. From preliminary data in the LoTurco lab, inducing the expression of ZFTA-RELA into different neural progenitor cells produces tumors of varying lethality and cellular composition. To define the cellular composition and subclonal diversity of ST-EPN tumors, we used single cell RNA-sequencing to …

Identifying The Cell Composition And Clonal Diversity Of Supratentorial Ependymoma Using Single Cell Rna-Sequencing, James He

Honors Scholar Theses

Ependymoma is a primary solid tumor of the central nervous system. Supratentorial ependymoma (ST-EPN), a subtype of ependymomas, is driven by an oncogenic fusion between the ZFTA and RELA genes in 70% of cases. We introduced this fusion into neural progenitor cells of mice embryos via in utero electroporation of a non-viral binary piggyBac transposon system containing ZFTA-RELA. From preliminary data in the LoTurco lab, inducing the expression of ZFTA-RELA into different neural progenitor cells produces tumors of varying lethality and cellular composition. To define the cellular composition and subclonal diversity of ST-EPN tumors, we used single cell RNA-sequencing …

The Role Of Subclonal Gene Mutations During Progression From Myelodysplastic Syndrome To Secondary Acute Myeloid Leukemia, Andrew John Menssen

Arts & Sciences Electronic Theses and Dissertations

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal bone marrow disorders characterized by ineffective hematopoiesis. Approximately 30% of MDS patients progress to secondary acute myeloid leukemia (AML). MDS is caused by somatic mutations in hematopoietic stem/progenitor cells and progression to secondary AML is associated with the acquisition and/or expansion of at least one subclone. We hypothesized that specific gene mutations would be enriched in subclones compared to founding clones, and that the order of mutation acquisition would be critical for clonal evolution and progression from MDS to secondary AML. Sequencing of paired MDS and secondary AML samples from 44 …

Molecular And Genetic Studies Of Robo2 Transcriptional Regulation In The Central Nervous System Of Drosophila Melanogaster, Muna Abdal Rahim Abdal Rhida

Graduate Theses and Dissertations

Drosophila Robo2 axon guidance receptor is a member of the evolutionarily conserved Roundabout (Robo) protein family that is involved in directing axons that cross the midline to the other side of the animal body. Robo2 roles mainly depend on two factors: The functional domains of the Robo2 protein, which is extensively studied, and the dynamic transcription of robo2 in various subsets of cells throughout embryogenesis which is not fully understood. Thus, knowing robo2 enhancers that transcriptionally regulate robo2 during embryogenesis is significant. To investigate robo2 potential enhancers, we screened 17 transgenic lines of Drosophila that were generated by Janelia Research …

Evaluating Insurance Approval Rates Of Exome Sequencing And Its Effect On Minority Patients' Access To Genetic Care, Katlyn Frane

Dissertations & Theses (Open Access)

Exome sequencing (ES) is often a standard step in the genetic testing process for patients with rare or complex disease. Despite clinical implementation of ES, insurance companies (payers) continue to deny this test. We investigated if the payer barrier is influenced by payer type, and if other demographic or clinical information correlated to ES approval and obtainment. To do this, a retrospective chart and clinical database review was completed on patients seen at a tertiary care center and community-based clinic. Patient demographics, clinical indications, and testing recommendations and outcomes were used to assess ES approval and obtainment. We found that …

Using Crispr-Cas9 To Characterize The Role Of Gli-Similar 3 (Glis3) In Insulin Regulation, Pancreatic Development, And Type 2 Diabetes, Lilyanne Grieve

Honors College Theses

The prevalence of type 2 diabetes continues to rise nationally and internationally, impacting millions of people worldwide. Type 2 diabetes results from insulin resistance leading to chronic hyperinsulinemia and dysfunction of the insulin producing β cells of the pancreas. While environmental factors can influence the development of type 2 diabetes, research has shown genetics are also involved. Gli-similar 3 (Glis3), a Krüppel-like zinc finger transcription factor, has been identified as a novel regulator of insulin transcription. Evidence has shown that loss-of-function Glis3 mutations decrease insulin expression, implicating Glis3 in the development of type 2 diabetes. However, the distinct role Glis3 …

Changes In Gene Sequence That Cause Discordances Involving Disease In Monozygotic Twins, Kacie Jacques

Thinking Matters Symposium

Identical twins or, monozygotic twins, occur when the egg in a mother is fertilized, but one zygote divides into two separate embryos. Monozygotic twins are considered to be genetically identical, but most twins often display discordances, some involving diseases or disorders. Some of these differences are due to environmental factors. For example, one twin may have diabetes due to diet. Recent literature has shown that some differences in monozygotic twins may be due to changes in gene sequence, as opposed to random, environmental or epigenetic factors. Identical twins from pedigrees with familial disease often show discordances. When looking at schizophrenia …