Genetics Commons^™

Effect Of Partial Ablation Of Skeletal Dynamin Related Protein 1 On Mitochondrial Health, Inflammation, And Fibrosis In A Mouse Model Of Duchenne Muscular Dystrophy, Tessa L. Duzz

Graduate Masters Theses

Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disorder characterized by muscle weakness, degeneration, fibrosis, and impaired muscle regeneration. Mitochondrial dysfunction is an early pathological feature of DMD and has been linked to excessive mitochondrial fission. Dynamin-related protein 1 (Drp1) is a central regulator of mitochondrial fission, a key process in regulating mitochondrial quality and function. Inhibition of Drp1-mediated mitochondrial fission has shown promise as a potential therapeutic target for alleviating pathology and dysfunction in dystrophic muscle. The objective of this study was to determine whether partial skeletal muscle-specific ablation of Drp1 could improve muscle pathology and mitochondrial health in …

From Genes To Streams: Mitochondrial Approaches To Population Monitoring Of The Santa Ana Sucker Catostomus Santaanae, Mariana Antonio

Electronic Theses, Projects, and Dissertations

This study was developed to use aquatic environmental DNA (eDNA) as a tool to detect the presence of the Santa Ana sucker (Catostomus santaanae), a federally threatened fish species, across the Santa Ana River in Southern California. Environmental DNA is any genetic material that an organism sheds into the environment. We can get an idea of what aquatic species are present when sampling water at a given site. We sequenced the complete mitochondrial genome (mitogenome) of the Santa Ana sucker and designed custom DNA primers to improve eDNA detection accuracy. These primers were selected based on high genetic …

Transcriptional Regulation In The Uterine Luminal Epithelium, Evelyn A. Carrion

Dissertations and Theses (Open Access)

Transcriptional Regulation in the Uterine Luminal Epithelium

Evelyn A. Carrion

Advisor: Richard R. Behringer, PhD

Abstract

The uterus is an organ comprised of multiple tissues that are essential for women’s health and reproduction. The uterus is composed of multiple tissue layers, including the perimetrium, myometrium, and the endometrium. The endometrium is the inner lining of the uterus, and contains the luminal epithelium, glandular epithelium, and stroma. The luminal epithelium is a simple columnar layer of cells that is necessary for embryo implantation. The uterus is derived in part from the embryonic precursor tissue called the Müllerian duct. There are no …

Regulation Of Müllerian Duct Mesenchyme Transcription During Mammalian Sex Differentiation, Haowen Li, Richard R Behringer, Rachel D Mullen

Dissertations and Theses (Open Access)

Sp7/Osterix (Osx) encodes a zinc-finger transcription factor of the Specificity-protein family discovered by Nakashima et al. at the MD Anderson Cancer Center. While primarily recognized for its role in osteogenesis, Osx has also been implicated in mammalian reproductive development, particularly in male sex differentiation, where Müllerian Duct (MD) regression occurs, mediated by anti-Müllerian hormone (AMH) signaling. AMH-induced regression signals are transduced by the mesenchymal tissue surrounding the ductal structure, known as the Müllerian Duct mesenchyme (MDM). It was discovered that AMH signaling is necessary and sufficient for driving Osx expression in MDM. A previous transgenic mouse reporter …

Mutational Analysis Of Domain Functions In The Yeast Decapping Enzyme Dcp2, Jellisa Ewan, Ambro Van Hoof

Dissertations and Theses (Open Access)

In yeast, the major mRNA decay pathway involves deadenylation of the 3’ poly-A tail, followed by decapping of the 5’ m7Gppp cap and subsequent 5’ to 3’ degradation or 3’ to 5’ degradation. This is carried out by Pan2/Pan3 and Ccr4/Not deadenylases, the decapping enzyme Dcp2, and Xrn1 and  RNA exosome exoribonucleases, respectively. The eukaryotic mRNA decapping enzyme complex, Dcp1/Dcp2, is essential in yeast, and deletion of either gene is lethal. However, the deadenylases that act upstream and the 5’ exoribonuclease that act downstream of the decapping step are not, even though they are all highly conserved with no known …

Investigating The Role Of Centromere Deletion In Chromosome Segregation, Azait Imtiaz

ETDs from 2020-2029

Centromeres are critical genomic regions responsible for ensuring accurate chromosome segregation during cell division. Disruptions in the structural or functional integrity of centromeric DNA could impair kinetochore assembly, leading to chromosome missegregation and chromosomal instability (CIN), a hallmark of various human diseases, including systemic sclerosis (SSc). This study investigated the contribution of centromeric DNA damage and deletion to CIN and explored potential pathogenic mechanisms relevant to SSc. We utilized hTERT-immortalized fibroblast cell lines (CHON-002 and BJ-5ta) to implement two complementary approaches: (i) treatment with bleomycin, a chemotherapeutic agent known to induce DNA double-strand breaks (DSBs), and (ii) targeted deletion of …

Elucidating The Function Of Yedk In Response To Dna Damage, Hank Munro

University Honors Theses

Apurinic/Apyrimidinic (AP) sites are one of the most prevalent forms of DNA damage. These lesions arise spontaneously or during base excision repair of modified DNA bases and are potentially mutagenic in both mammalian and bacterial cells. 5-hydroxymethylcytosine binding, ES cell specific (HMCES), a protein found in eukaryotic cells, has been shown to form a stable DNA-protein crosslink with AP sites in single stranded DNA and to reduce the number of AP sites occurring either spontaneously or after alkylative DNA damage, resulting in increased genome stability. YedK, the Escherichia coli ortholog of HMCES exhibits some of the same biochemical properties as …

The Evolutionary Response Of HawaiʻI ʻAmakihi (Chlorodrepanis Virens) To The Introduction Of Avian Malaria (Plasmodium Relictum), Gabrielle Atkinson

Doctoral Dissertations

The emergence of novel pathogens can impose intense selective pressures on natural populations, driving rapid evolutionary change or precipitating population collapse. In Hawaiʻi, the introduction of avian malaria (Plasmodium relictum) and its mosquito vector (Culex quinquefasciatus) have caused severe declines and extinctions among native forest birds. Yet some populations of Hawaiʻi ʻamakihi (Chlorodrepanis virens) persist across a broad elevational and disease gradient, providing a powerful natural system for examining the genomic basis of rapid adaptation, the role of gene flow in adaptive response, and the potential for parallel evolutionary responses. This dissertation integrates genomic, population genetic, and transcriptomic approaches to …

Marine Heatwaves And Fish Reproduction: Endocrine Responses In The Eurythermal Sheepshead Minnow (Cyprinodon Variegatus), Isabel Villafuerte

Master's Theses

Marine heatwaves associated with climate change are increasing in frequency and severity, posing significant threats to fish populations in shallow habitats such as estuaries and salt marshes. Because temperature is a primary regulator of fish reproduction, understanding how heatwaves affect reproductive physiology is critical for anticipating the biological consequences of ongoing climate change for coastal fishes. Here we examined how simulated heatwave conditions affect the reproductive hypothalamic-pituitary-gonadal (HPG) endocrine axis in the estuarine sheepshead minnow (Cyprinodon variegatus), a eurythermal fish well suited to studying thermal stress responses in estuarine environments. Adult sheepshead minnows acclimated to a daily oscillating …

Quantifying Genetic Diversity In Nematode Feeding Rate, Jacob King

Honors Theses

Understanding how populations persist under changing environmental conditions is a central question in ecology and evolutionary biology. Variation in traits related to resource acquisition may play a key role in determining population survival when resources are limited or fluctuate over time. In this study, I investigated how variation in feeding-related traits influences population persistence using a combination of computational modeling and laboratory experiments. I developed a stochastic, individual-based consumer–resource model to simulate population dynamics across varying levels of trait variance and resource regimes. Across 60,000 simulated populations, increased trait variation consistently reduced extinction risk and extended persistence time, although the …

Using The Flexon Approach To Rnai For Analysis Of Gene Function In Gonadal Development In C. Elegans, Andrew D. Spalding

Undergraduate Theses

C. elegans, a nematode worm, was used as a model organism to analyze the developmental effects of knocking down the expression of genes that are both essential to worm viability and highly enriched in reproductive tissues. In earlier research, approximately 70 C. elegans genes were identified that are both gonad-enriched and essential. To prioritize which genes should be the focus of future studies, a new strain of C. elegans was produced with three specific genetic variations that: 1) silence essential, somatic gonad-enriched gene expression, 2) limit the effects of this gene silencing to the gonad, and 3) yield a …

Investigating The Taxonomic Uncertainties Of Potentilla Rupincola, Natalie Elizabeth Hieber

Master's Theses

Landscape stewardship is an integral role for land managers that becomes more important when rare or endangered species occur within managed areas. Conservation across the landscape is a primary concern for land managers, but resources allocated for conservation can be limited due to many competing goals. Taxonomic uncertainty surrounding rare and endangered taxa, particularly plant taxa, that have historically been classified solely using morphological features further complicates conservation planning. One such taxon is Potentilla rupincola, a rare plant endemic to the eastern Rocky Mountains in Colorado. For over a century, botanists have debated whether P. rupincola is a distinct species …

Sorghum Grain Secondary Metabolites And Underlying Genetics To Reduce Foodborne Pathogens In Poultry, Maria A. Conti

All Dissertations

The rise in antibiotic-resistant pathogens poses a threat to the poultry industry's ability to maintain animal health, prompting growing interest in alternatives to synthetic antibiotics. The use of non-tannin sorghum [Sorghum bicolor (L.) Moench] in poultry rations offers a valuable alternative, as this cereal grain has a high bioactive profile that can provide health benefits, including antimicrobial (AM) activity. The scope of this study was to examine the AM potential of non-tannin sorghum grain against Clostridium perfringens, a major foodborne pathogen that negatively impacts poultry health and production. To that end, the inhibitory effects of a non-tannin sorghum …

The Genetic Basis Of High Transformation Efficiency In The Model Yeast Saccharomyces Cerevisiae, Mary Kathryn E. Cheek

Biological Sciences Undergraduate Honors Theses

Transformation, a type of horizontal gene transfer, describes the uptake, maintenance, and integration of environmental DNA by cells. Despite the known effects of transformation on evolutionary processes, little is known about the genetic basis of this phenomenon. Saccharomyces cerevisiae is a eukaryote able to transform at quantifiable rates when made chemically competent and treated with a heat shock. S. cerevisiae also has variation in transformation efficiencies between various strains, and high recombination rates allow for sufficient allele “shuffling” in intercross populations. This project utilizes a bulk segregant analysis approach to compare sequencing data between transformant pools and non-transformant pools of …

Dissecting The Complex Genomic Landscape Underlying Oxidative Stress Resistance Using Natural Variation In Yeast, Sonali Lakshika Anne Lenaduwe

Graduate Theses and Dissertations

Stress is experienced across the tree of life. Survival in fluctuating environments depends on a robust genetic architecture. This dissertation examines the genetic and metabolic determinants underlying one such adaptive response: cross-protection. Leveraging natural variation in the stress responses of budding yeast, Saccharomyces cerevisiae, I examine the genetic variation contributing to ethanol-induced cross-protection against oxidative stress. Acquired stress resistance, in which mild pre-exposure improves survival to subsequent stresses, is prevalent across diverse organisms and can involve both same-stress and cross-protection. Using high-throughput bulk segregant analysis (BSA-seq) and advanced intercross mapping populations derived from natural yeast isolates, I identify quantitative trait …

Precursor Rna Properties Driving Cryptic 3’ Splice Site Selection In Sf3b1 Mutant Malignancies, Austin A. Herbert

All Dissertations

SF3B1 is a core component of the spliceosome involved in branch point recognition and 3’ splice site selection. SF3B1 is commonly mutated in myelodysplastic syndromes and other blood cancers with the K700E mutation being the most frequent. This mutation of SF3B1 induces cryptic 3’ splice site activation in hundreds of genes. Introduction of such cryptic 3’ splice sites can shift the reading frame of protein coding transcripts, causing the transcript to be tagged for nonsense-mediated decay or resulting in the production of a truncated protein. Both these scenarios can lead to down-regulated protein expression. Sequence and structural properties of precursor …

Genetic Screen For Regulators Of Pol4, A Dna Repair Polymerase In Saccharomyces Cerevisiae, Pasang Dolma Sherpa

Theses and Dissertations

In Saccharomyces cerevisiae, DNA polymerase 4 (POL4) is the beta repair polymerase, the product of the POL4 gene, and is involved in base excision repair (BER) and microhomology-mediated end joining (MMEJ). Despite its involvement in these repair pathways and its conservation across eukaryotes, deletion of POL4 shows no detectable phenotype under standard laboratory conditions. I hypothesized that unknown genes act as backup systems, providing redundant activities that allow pol4Δ cells to survive. To test this, a genetic screen for mutants showing synthetic lethality with pol4Δ was implemented. I constructed a strain lacking the POL4 gene and carrying …

Abnormal Trafficking And Processing Of Multiple Matrix Metalloproteinases Drive Cartilage Defects In Congenital Disorders Of Glycosylation, Chia-Lun Wu

All Dissertations

Congenital Disorders of Glycosylation (CDG) are rare metabolic diseases caused by defects in glycosylation. Despite identification of over 200 CDG types, the mechanisms linking glycosylation defects to diverse clinical phenotypes remain unclear. This dissertation uses zebrafish models of PMM2-CDG and STT3-CDG to redefine CDG pathogenesis, shifting from a simple glycan deficiency model to one involving disrupted cellular spatial organization.

We identify a protease-dependent pathway underlying craniofacial cartilage defects. Specifically, defective proteolytic processing of N-cadherin, a key adhesion molecule in chondrogenesis, is a central driver of pathology. We further uncover an unconventional trafficking mechanism in which ER stress and altered secretory …

Using The Flexon Approach To Rnai To Identify Essential Genes That Affect Gonadal Development In C. Elegans, Joyce S. Lefevers

Undergraduate Theses

To elucidate the molecular role of essential genes in the gonadal development of Caenorhabditis elegans (C. elegans) it is necessary to utilize specialized molecular techniques such that the phenotypic effects of gene knockdown can be studied while the viability of the organism is preserved. Shaffer and Greenwald (2022) developed the floxed exon (flexon), a tool that improves upon previous approaches to spatiotemporal control of gene expression. The flexon subunit is made up of an artificial exon with a stop cassette flanked by artificial introns which, when inserted into a gene of interest, prevents the expression of that gene. …

From Bench To Bedside: Unraveling The Role Of Sarm1 In Chronic Human Neurodegenerative Disease, Caitlin Dingwall

Arts & Sciences Graduate Student Theses and Dissertations

Axon degeneration (AxD) is an early and often causative event in many neurodegenerative diseases, yet no treatments exist to halt the breakdown of axons. In healthy axons, the axon survival factor NMNAT2 inhibits SARM1, the central executioner of programmed axon degeneration. NMNAT2 is a highly labile protein produced in the soma and trafficked into the axon. Nerve injury blocks axonal transport and leads to rapid depletion of axonal NMNAT2, causing NMN buildup and NAD+ loss. Recent breakthroughs led to the discovery that SARM1 is activated by an increase in the NMN to NAD+ ratio. While the SARM1 axon degeneration pathway …

Biomechanical Effects Of Bilateral Torsion And Skeletal Fusion: A Case Study, Linnéa Forbes

Honors Projects

As part of both a personal endeavor and an academic project, I have investigated the aetiology and treatment of seemingly idiopathic and debilitating leg pain in a patient over the past 10 years. Via collaboration with medical professionals at Cincinnati Children’s Hospital, Cincinnati Premier Physical Therapy, and Cincinnati Women’s TriHealth, I have identified sources of pain at the anatomical level. The combination of internal femoral torsion, external tibial torsion, pes planus, and bony fusions appear to be major perpetuators of the pain. An effective treatment continues to be evasive. To date, I have attempted to find answers through genetic approaches, …

Dissecting The Etiology Of Alcohol Use Disorder By An Integrative Heritable Component Approach, Ivy Garrenton

Computer Science Theses & Dissertations

Alcohol Use Disorder (AUD) is a pervasive condition characterized by complex interplay among genetic, phenotypic, and environmental factors. Although previous studies have identi fied genetic loci associated with alcohol consumption, these efforts have not captured the genetic heterogeneity and gene-environment interactions underlying AUD pathogenesis. To address this critical gap, we developed a novel statistical methodology that integrates phenotypic, genotypic, and environmental data through an environmentally modified Genetic Relationship Matrix (GRM) to derive AUD-related traits with enhanced heritability.

This approach demonstrated superior performance in both simulated and real-world datasets. Traits derived using the environmentally modified GRM exhibited significantly higher estimated heritability …

Understanding P53 Regulation On Transposable Elements In Cancer, Xuan Qu

Arts & Sciences Graduate Student Theses and Dissertations

Transposable elements (TEs), traditionally known as “jumping genes”, are known to have the ability to move in the genome and alter the activation of transcriptions from nearby genes. Taking up nearly half of the human genome, TEs have evolved, and some have been selected to play important roles in biological processes. We found that in human diseases such as cancer, global hypomethylation resurrects many ordinarily silenced TEs. These TEs can often serve as alternative promoters for oncogenes and play functionally meaningful roles in driving disease processes. One of the top genetic mutation status that correlates with differential numbers of TE …

Multiplex Functional Assessment Of Variant Effect In The Retinal Transcription Factor Crx, James Lewis Shepherdson

Arts & Sciences Graduate Student Theses and Dissertations

The transcription factor Cone-Rod Homeobox (CRX) is a master regulator of photoreceptor cell fate. Sequence variants in CRX can cause Retinitis Pigmentosa, Cone-Rod Dystrophy, and Leber Congenital Amaurosis, all inherited causes of vision loss and blindness. CRX is the only gene implicated in the pathogenesis of all three of these diseases, which present with both rod- and cone-centric phenotypes of varying age of onset and severity. Several CRX variants have been reported to cause severe dominant disease through antimorphic genetic interactions with wild-type CRX, and yet these mutations are adjacent to variants which are benign or only cause mild, recessive …

Comparative Evolution Of Caenorhabditis Hermaphrodites, James Francis Kennedy

Theses and Dissertations

The Caenorhabditis genus produced three independently-evolved hermaphroditic species, C. elegans, C. briggsae, and C. tropicalis. This convergence happened by the independent co-option of male programs for use in a female body. This required two distinct steps: (1) mutations in the sex-determination pathway that activated spermatogenesis in XX animals, and (2) mutations that expressed one of the redundant sperm activation signals in XX animals. My project focused on characterizing how sex-determination genes work in C. briggsae and C. tropicalis. Loss-of-function alleles were used to compare the core sex-determination pathway to that of C. elegans. I found that the somatic sex-determination pathway …

The Yeast Checkpoint Kinase Mec1p Functions In Transcription Termination By Facilitating Recruitment Of Pcf11p And Regulating The Torpedo Exonuclease Rat1p, Riddhi Patel

Theses and Dissertations

My dissertation includes two projects, centered on transcription regulation by checkpoint kinases of the DNA damage response (DDR). The first project focused on the role of checkpoint kinase Mec1p in transcription termination and regulation of the torpedo exonuclease Rat1p. Termination, closely linked with pre-mRNA 3’ processing, dissociates RNA polymerase II (RNAPII) from DNA and releases the nascent RNA transcript. Efficient termination is required for maintaining a pool of RNAPII that is available for re-entry into new transcription cycle. Previous results showed that inactivation of Mec1p in the absence of exogenous genotoxic stress downregulates the efficiency of transcription termination. This study …

Toward Interpretable Multi-Omics Multimodal Biomedical Artificial Intelligence, Yanjun Lyu

Computer Science and Engineering Dissertations

The complexity of human disease arises from biological processes that unfold across multiple scales, from molecular variation through cellular function, tissue organisation, brain phenotypes, each of which is associated with distinct measurement modalities, regularities, and characteristic. Contemporary biomedical artificial intelligence has brought the opportunity to reveal the complexity with in; however, its methodological default, in which models are trained on most readily available modality, does not adequately engage with the multi-scale connected structure by which biological meaning is constituted. The research area of multi-omics and multi-modal AI for biomedicine remains at an early exploratory stage, and the work presented in …

A Framework For Characterizing The Peripheral Immune Isonome Using Long-Read Single-Cell Rna Sequencing And Its Relevance To Neurological Disease, Patricia Hayes Doyle

Theses and Dissertations--Neuroscience

Long-read single-cell RNA sequencing provides an opportunity to understand human health and disease at isoform resolution, revealing cellular diversity and disease mechanisms difficult to resolve with bulk or short-read methodologies.

Using a modified PIPseq workflow and computational pipeline adapted for Oxford Nanopore (ONT) sequencing, we profiled isoform usage across immune cells, integrating marker expression and isoform discovery, generating the largest long-read single-cell dataset of human immune cells from a single individual to date. We identified non-canonical protein-coding variants of GZMB and CD3G enriched in unexpected cell types. We also discovered novel transcripts from CMC1 and LYAR with cell-type-specific signatures that …

Tmem116 Crispr-Mediated Knockout Prevents Proper Lens Regeneration In Iberian-Ribbed Newts, Damien T. Mann

Honors Theses and Capstones

Eye diseases like cataracts, age-related macular degeneration (AMD), and glaucoma are widespread and detrimental conditions affecting many people across the globe. While there are reliable and successful treatments for those with cataracts that can reverse vision impediments, others like glaucoma and AMD have limited treatment options. Additionally, eye damage resulting from these conditions is commonly irreversible, establishing a need for new treatment options. The Iberian-ribbed newt, Pleurodeles waltl, is a salamander species primarily studied for their amazing regenerative capabilities. Particularly, these newts are capable of de novo lens regeneration after a complete resection, providing a unique opportunity to study regeneration …

Perfluorooctane Sulfonate (Pfos)-Induced Disruption Of Mitochondrial Activity And Cell Adhesion In Liver Cells, Phuong Dam Nam Tran

Graduate Theses/Dissertations

Perfluorooctane sulfonate (PFOS) is a persistent environmental pollutant associated with potential hepatoxic effects and other health risks. Despite its widespread distribution, the mechanisms underlying its toxicities remain to be fully understood. To investigate PFOS toxicology, my study utilized HepG2 and THLE-2 human hepatic cell models to replicate conditions reflecting PFOS accumulation in the liver. Cell viability, cell stress, and cell death assays were conducted to assess the toxicological influence of the chemical on both cell lines. Total RNA extraction was performed, followed by cDNA sequencing, and RT-qPCR. The XTT viability assay revealed a dose-dependent decrease in number of viable cells …