Genetics and Genomics Commons^™

Life History Inhibits Deleterious Effects Of Dams On Genetic Health And Structure Of A Headwater Stream Fish, Riley Phelps

Electronic Theses and Dissertations

Habitat loss, fragmentation, and land use changes in river networks are common globally. The resulting fragmentation of landscapes and riverscapes threatens biodiversity and can affect dispersal and subsequently, gene flow and genetic health of species. Headwater streams are an integral part of river networks and contribute to biodiversity by providing habitat for temporary and permanent residents, yet they are easily altered and fragmented. The sandhills chub (Semotilus lumbee) is an endemic headwater leuciscid that lives in highly fragmented streams of the sandhills ecoregion in North and South Carolina, USA. New knowledge on the population genetics of the sandhills chub is …

Sibship Analysis Of Fall And Spring Spawn Gulf Sturgeon Eggs In The Choctawhatchee River, Florida, Lyric Mccullouch

Honors Theses

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is an anadromous species that inhabits rivers along the northern Gulf of Mexico. Facing challenges from overfishing and habitat alteration, the Gulf sturgeon is listed as threatened under the Endangered Species Act. This study investigated the genetic distinctiveness of fall and spring spawning groups of Gulf sturgeon in the Choctawhatchee River, a critical habitat for the species. In this study, I used microsatellite loci to analyze Gulf sturgeon eggs previously collected in the fall and spring of 2019 and 2020. The goals of this study were to verify the genetic identity of …

Role Of Evolutionarily Conserved G4 Structures In Enhancer-Promotor Interactions, Shahem Alqudah

Honors Theses

Gene regulation is governed by complex networks of interactions between enhancers and promoters, regions of the genome that are typically distant from one another yet functionally linked through chromatin looping. Recent research has revealed the significant role of Gquadruplexes (G4s) in facilitating these interactions. This thesis explores the role of long Gquadruplex regions (LG4s) in enhancer–promoter communication, proposing that these regions mediate physical interactions between enhancers and their target promoters through direct G4:G4 interactions. Using a chromatin conformation capture (EQuIP-seq), electrophoretic mobility shift assays (EMSA), and luciferase reporter assays, the study demonstrates that LG4s may drive gene expression by promoting …

A Review On Treatment, Prevention, And Research Of Worldwide Parasitic Disease: Toxoplasmosis, Hannah Skinner

All Theses

Toxoplasmosis is a worldwide, yet often overlooked, parasitic disease caused by the protozoan parasite, Toxoplasma gondii. The parasite is capable of infecting humans and almost all warm-blooded vertebrates. Over a million people are infected in the United States with toxoplasmosis each year. Most infections are asymptomatic but severe cases can lead to vision impairment, neurological disorders, and congenital birth defects. T. gondii is transmitted through undercooked meat, infected feline feces, or contaminated water and soil. The burden of T. gondii infection is most notable in livestock, felines, and immunocompromised humans. Despite being a widespread disease, toxoplasmosis is neglected in …

Chromosome Evolution Model Reveals Hidden Variation In Karyotype-Driven Speciation In Ferns, Thomas Buchloh

All Theses

Because karyotype change commonly generates reproductive isolation between diverging species, rapid karyotype evolution, like that seen in plants, may increase the total rate of diversification. However, few studies have investigated this predicted relationship. Tests of this prediction have identified a positive correlation between the rate of karyotype change (specifically whole genome duplications) and diversification, but tests have been restricted to relatively small and young clades. Fortunately, novel macroevolutionary models have recently become available to investigate patterns of karyotype evolution in large phylogenies, providing new opportunity to investigate variation in karyotype driven diversification. Ferns are one of the most karyotype rich …

Implications Of Type Iv Pilus Retraction For Dna Uptake By Acinetobacter Baumannii, Yafan Yu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Horizontal gene transfer (HGT) via natural competence allows bacteria to incorporate extracellular DNA (eDNA) into their genomes, facilitating genetic diversity and adaptation. In Acinetobacter species, natural competence depends on DNA binding and uptake mediated by type IV pili (T4P). T4P are dynamic extracellular filaments composed primarily of the major pilin subunit PilA, along with a few minor subunits. T4P drive a range of cellular functions including twitching motility, biofilm formation, and DNA uptake, with some functions dependent on pilus retraction and others not. However, how Acinetobacter T4P bind DNA and how T4P/eDNA interactions impact biofilm formation remain unclear. Here, I …

Integrating Genomic And Phenomic Breeding Tools For Wheat Stem Sawfly Resistance In Hard Winter Wheat, Sydney E. Graham

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The wheat stem sawfly (WSS; Cephus cinctus) is an insect pest that affects wheat (Triticum aestivum) in the Northern Great Plains. This pest causes stem cutting that makes the plants susceptible to lodging and results in up to 30% yield loss. The primary management strategy for producers is utilizing host plant resistance, for which the main trait is stem solidness. This trait increases the pith thickness and provides resistance to the WSS by increasing larval mortality and reducing stem cutting. While stem solidness is largely controlled by a known major gene (SSt1), the phenotypic expression is also …

Hypoxia Induced Ribosomal Rna Fragmentation Mediated By Rnase L, Vanessa Kristina Pizutelli, Dimitri G Pestov

Rowan-Virtua Research Day

Ischemic injury contributes to a range of global pathologies. Ischemia/Reperfusion Injury (IRI) is a paradoxical phenomenon that involves an initial restriction of blood flow followed by a sudden restoration of perfusion. This type of injury takes place in conditions such as myocardial infarction, acute kidney disease, and ischemic stroke and often leads to cellular death. Additionally, IRI exacerbates post-surgical outcomes and plays a role in graft dysfunction and transplant rejection. Despite efforts to develop therapies targeting known IRI pathways, clinical trials have largely been unsuccessful, underscoring the need for alternative mechanisms and biomarkers associated with IRI-induced apoptosis. Reactive oxygen species …

Investigating The Effects Of Sod1 Knockout On Oxidative Stress And Stress Coping Styles In Zebrafish Using Crispr Technology, Tai Prauner, Ryan Wong

Theses/Capstones/Creative Projects

Reactive oxygen species are byproducts of cellular metabolism that, when not efficiently neutralized, can damage DNA, proteins, and lipids. Superoxide dismutase 1 (SOD1) is an antioxidant enzyme that converts superoxide radicals into less harmful molecules. While its molecular function is well documented, the role of SOD1 in shaping stress-related behavior remains underexplored. This project aimed to establish foundational tools for studying the behavioral impact of SOD1 knockout across proactive and reactive stress-coping styles in zebrafish.

To support future gene-editing experiments, microinjection and breeding protocols were refined across wildtype AB, proactive, and reactive zebrafish lines. No embryos were injected with CRISPR-Cas9 …

Decoding Bacterial Resilience: Srnas And Sigma Factors In Stress Adaptation And Persistence Of Salmonella, Anita Nguyen

Honors Theses

Small RNAs (sRNAs) are noncoding RNA molecules in bacteria that function primarily to regulate gene expression, including those associated with stress. The Borchert Lab has identified 173 sRNAs and > 500 sRNAs that are responsive to desiccation and carbon starvation (c-starvation), respectively. Prokaryotic transcription involves an RNA Polymerase (RNAP) that transcribes DNA into RNA. RNAP involves sigma factors, which recognize promoters for the initial steps of RNA synthesis. The Borchert Lab has determined that there are significant overlaps between sRNAs expressed in cells subjected to both short-term durations and long-term durations of carbon starvation. Salmonella enterica serovars can have outbreaks associated …

A Genetic And Spatial Analysis Of The Last Megafaunal Species (Tapirus Terrestris) In The Paraguayan Dry Chaco Forest, Emily Bowers

LSU New Orleans Theses and Dissertations

No abstract provided.

Investigating The Role Of Ilv1 On Stress Response In Saccharomyces Cerevisiae, Luke H. Beachboard

Honors Theses

Saccharomyces cerevisiae, a model organism within molecular genetics, is also known for its broad role within baking, brewing, biofuel, and pharmaceutical industries. An unpublished study at The University of Tennessee at Chattanooga observed decreased cell viability in an ILV1 Knockout strain of S. cerevisiae when exposed to environmental stressors. A subsequent study at The University of Tennessee at Chattanooga found expression levels of the candidate genes to be significantly altered within the ILV1 Knockout strain relative to the BY4743 Wildtype strain, demonstrating the reality of a pleiotropic role within ILV1. Now, this study aims to further investigate this peculiar characteristic …

Translation Of The Carcinogenic Dna Breakage-Repair Inhibition Mechanism For Hexavalent Chromium To Its Key Targets: Lung Epithelial Cells, Lung Tissue And Impacts On The Genome., Idoia Meaza Isusi

Electronic Theses and Dissertations

Lung cancer is the leading cause of cancer death worldwide. Hexavalent chromium [Cr(VI)] is a human lung carcinogen with widespread occupational and environmental exposure. Despite the known health risks, how Cr(VI) causes lung cancer remains unclear. This dissertation investigates the mechanisms of Cr(VI)-induced carcinogenesis. Cr(VI) causes DNA damage, specifically DNA double strand breaks, and inhibits homologous recombination repair, a high-fidelity repair pathway. Unrepaired DNA double strand breaks or those repaired through error-prone pathways, progress to chromosomal damage, and chromosome instability. The latter is a common characteristic of Cr(VI)-exposed cells, and a hallmark of lung cancer. Although the mechanism of Cr(VI)-induced …

Gender And Race Stigma Consciousness Denialism And Reactions To Race And Gender Measures, Valerie Partida, Alicia Sylvester, Magel Baker

Celebrating Scholarship and Creativity Day (2018-)

The study examined whether denialism, defined as holding problematic stigma consciousness scores in, predicts emotional reactions to race- and gender-related survey measures. Specifically, we asked whether race stigma consciousness scores correlate with feeling upset when completing race scales, and whether gender stigma consciousness scores correlate with either positive or negative reactions to gender scales. Undergraduate students in introductory psychology courses participated (N = 38; 61 % women/gender minority, 39 % men; 21% POC, 79% White). Measures of students’ awareness of racial and gender discrimination (Pietri et al., 2018) were scored such that high scores meant that students of color (POC), …

Cloning And Heterologous Expression Of Human Nachrs And A Unique Spider Venom Toxin, Christine M. Vega

Theses and Dissertations

Drug development research has long focused on synthesizing novel therapeutics while overlooking isolation from naturally available sources. Recently, the discovery of the therapeutic effects of highly bioavailable animal venom caused the field of venom research to soar in popularity. Animal venom serves as a natural, sophisticated tool optimized over millions of years by evolution with the ability to bind to ion channels such as nAChRs, non-specific ligand-gated ion channels distributed throughout the human nervous system, with high selectivity and specificity. However, purifying individual venom toxins from crude venom is challenging due to its availability. Therefore, synthesizing large quantities of venom …

Therapeutic Applications Of A Novel Humanized Monoclonal Antibody Targeting Chemokine Receptor Ccr9 In Pancreatic Cancer, Hannah G. Mcdonald, Anna M. Reagan, Charles J. Bailey, Mei Gao, Muqiang Gao, Angelica L. Solomon, Michael J. Cavnar, Prakash Pandalai, Mautin Barry-Hundeyin, Megan Harper, Justin A. Rueckert, Ángela Turrero, Araceli Tobio, Anxo Vidal, Daniel Roca-Lema, Elia Álvarez-Coiradas, Pablo Garrido, Laureano Simón, Joseph Kim

Markey Cancer Center Faculty Publications

The relative failure of immune checkpoint inhibitors in pancreatic ductal adenocarcinoma (PDAC) despite having a dense, immunosuppressive tumor microenvironment highlights the need to target alternate/escape pathways. We have previously examined C–C chemokine receptor type 9 (CCR9) as a candidate immune checkpoint and developed a targeted, humanized monoclonal antibody (SRB2). Cytotoxicity of SRB2 was evaluated in vitro and in vivo. CCR9 expression on PDAC cells/tissues, immune components of patient-derived organoids (PDOs), and antibody-dependent cell-mediated cytotoxicity were examined. In PANC-1 and MIA PaCa-2 cell lines, we demonstrated highest CCR9 expression; however, no direct cytotoxic effect was observed with SRB2 treatment. In PANC-1 …

The Roles Of Rnt1 And Putative Endoribonucleases In Eukaryotic Mrna Degradation, Lee-Ann Notice-Sarpaning

Dissertations and Theses (Open Access)

Endoribonucleases initiate degradation by cleaving RNAs internally. Mutations in these enzymes have been shown to cause diseases such as cancer, developmental disorders, and neurodegenerative diseases. Yet, eukaryotic endoribonucleases have not been well studied, especially with regard to their role in nuclear mRNA degradation. Rnt1 is a Saccharomyces cerevisiae (budding yeast) nuclear endoribonuclease and homolog of human Drosha with well-characterized roles in the processing of ncRNAs. The enzyme recognizes and cleaves double-stranded RNA stems containing a terminal tetraloop with an AGNN consensus sequence. However, the scope and consequence of its function in mRNA degradation has heretofore been unclear. Previous studies have …

Evaluating Cancer Rates, Cancer Types, And Variant Hotspots Between Different Races And Ethnicities In Individuals With Li-Fraumeni Syndrome, Hillary Esplen

Dissertations and Theses (Open Access)

Li Fraumeni Syndrome (LFS) is a cancer predisposition syndrome that increases the risk for numerous cancer types in both children and adults. In the general population, incidence rates for various cancer types differ among races and ethnicities. Although a few germline TP53 pathogenic/likely pathogenic (P/LP) variants in those with LFS have been studied and associated with specific populations, such as the South and Southeast Brazil founder variant, p.Arg337His, there still lacks research on the variable expressivity of cancers within the LFS population based on specific variant, race and/or ethnicity. This study aims to describe the specific TP53 germline variants, the …

Elucidating The Multi-Omics Of Early-Onset Colorectal Cancer, Jumanah Alshenaifi

Dissertations and Theses (Open Access)

The incidence and mortality rates of sporadic early-onset colorectal cancer have increased in recent decades, but there is no clear etiological basis for this trend. EOCRC is commonly defined as colon and rectal cancers diagnosed before the age of 50 years. The rising incidence of EOCRC has made it the second most common cancer and the third leading cause of cancer death in this age group. The rising incidence of EOCRC is also documented internationally in more than 20 countries across different continents. Clinically, EOCRC has a distinct, more aggressive clinical profile than LOCRC. While approximately 15% of EOCRC cases …

Impact Of Personal And Family History Of Huntington's Disease On The Decision And Ability To Obtain Life, Long-Term Care, And Disability Insurance, Karli Livingston

Dissertations and Theses (Open Access)

Huntington’s disease (HD) is an inherited, neurodegenerative condition characterized by a clinical triad of motor, cognitive, and psychiatric symptoms. Individuals diagnosed with HD manifest characteristic symptoms of the disease including motor and cognitive changes, and they may or may not have undergone genetic testing to confirm the diagnosis. Individuals at-risk for HD are those who have not yet undergone genetic testing for HD, but have a first- or second- degree relative diagnosed with the disease. Genetic testing for HD is categorized into two forms: predictive and confirmatory. However, many individuals choose not to pursue testing due to a fear of …