Genetics and Genomics Commons^™

The Role Of Presynaptic Proteins In Alcohol Sensitivity And Tolerance, Madhumitha Gundluru

Honors Theses

Mammalian Unc13 (Munc13) and Drosophila Unc13 (Dunc13) are presynaptic active zone proteins essential for synaptic vesicle docking and priming in a neuron. Alcohol binds to the C1 domain of Munc13, which inhibits DAG binding. The reduction in DAG binding by Munc13 decreases the probability of vesicle fusion with the membrane, decreasing neurotransmitter release. Heterozygotes for a Dunc13 loss-of-function allele are behaviorally resistant to alcohol, physiologically resistant to alcohol, molecularly resistant to alcohol, and self-administer significantly more alcohol than control flies. Therefore, genetically reducing Dunc13 mimics a state of alcohol tolerance in the fly. The two main Dunc13 isoforms, Dunc13A and …

Mesoderm-Specific Transcript Has A Role In The Systemic Regulation Of Obesity, Maria J. Orellana Rosales

Thinking Matters Symposium

Mesoderm specific transcript (Mest) expression in white adipose tissue (WAT) is variable in genetically identical mice. Previous studies have shown a connection between Mest high expression and propensity for fat mass expansion. WAT and liver crosstalk has been well documented with hormone-like peptides signaling and regulating important metabolic pathways. The aim of this study is to investigate the correlation between these circulating factors and Mest expression in mice after exposure to a high fat diet (HFD). A group of 120 C57B6/J mice, males and females, were exposed to a HFD (Western Diet, 40 kcal% fat) for 4 weeks (8-12 weeks …

Sirt6 Deficiency Promotes Senescence And Age-Associated Intervertebral Disc Degeneration In Mice, Pranay Ramteke, Bahiyah Watson, Mallory Toci, Victoria Tran, Shira N Johnston, Maria Tsingas, Ruteja Barve, Ramkrishna Mitra, Richard Loeser, John Collins, Makarand Risbud

Department of Orthopaedic Surgery Faculty Papers

Intervertebral disc degeneration is a major risk factor contributing to chronic low back and neck pain. While the etiological factors for disc degeneration vary, age is still one of the most important risk factors. Recent studies have shown the promising role of SIRT6 in mammalian aging and skeletal tissue health, however its role in the intervertebral disc health remains unexplored. We investigated the contribution of SIRT6 to disc health by studying the age-dependent spinal phenotype of mice with conditional deletion of Sirt6 in the disc (Acan^CreERT2; Sirt6^fl/fl). Histological studies showed a degenerative phenotype in knockout mice …

Genome Annotation Of Stargaze, Madison R. Murray

Honors Theses

Bacteriophages are viruses which solely infect bacteria. They are one of the most abundant and diverse biological entities, yet there is a limited amount of information on these viruses, including their gene functions. Several previously unknown phages have been discovered including Stargaze, whose bacterial host is Mycobacterium Smegmatis. Characterization of phage genes and their functions deepen our understanding of phages and potentially contribute to the broader biomedical effort associated with phages ability to combat bacterial infections. Stargaze is a G5 subcluster phage and it only has one other related phage in its cluster, that phage is from Madagascar. Using a …

Performance Of Lasso And Ridge Regression For Variable Selection In Genome-Wide Association Studies Of Maize Flowering Time, Dipok Deb

Data Science and Data Mining

Genome-Wide Association Studies (GWAS) are instrumental in identifying genetic variants linked to complex traits, providing valuable insights into trait heritability and biological mechanisms. This study applies GWAS to investigate flowering time in maize, a critical adaptive trait, using a diverse dataset of 5,000 recombinant inbred lines across eight environments. Traditional GWAS methods often encounter challenges in high-dimensional datasets due to the presence of multiple small-effect genetic loci. To address this, we compared two penalized regression methods—LASSO and Ridge regression—to perform variable selection and regression analysis within a GWAS framework. LASSO effectively reduced the number of predictors by selecting the most …

Lifespan Reference Curves For Harmonizing Multi-Site Regional Brain White Matter Metrics From Diffusion Mri, Alyssa H. Zhu, Talia M. Nir, Shayan Javid, Julio E. Villalón-Reina, Amanda L. Rodrigue, Lachlan T. Strike, Greig I. De Zubicaray, Katie L. Mcmahon, Margaret J. Wright, John Blangero

School of Medicine Publications

Age-related white matter (WM) microstructure maturation and decline occur throughout the human lifespan, complementing the process of gray matter development and degeneration. Here, we create normative lifespan reference curves for global and regional WM microstructure by harmonizing diffusion MRI (dMRI)-derived data from ten public datasets (N = 40,898 subjects; age: 3–95 years; 47.6% male). We tested three harmonization methods on regional diffusion tensor imaging (DTI) based fractional anisotropy (FA), a metric of WM microstructure, extracted using the ENIGMA-DTI pipeline. ComBat-GAM harmonization provided multi-study trajectories most consistent with known WM maturation peaks. Lifespan FA reference curves were validated with test-retest data …

Genomic Structure Among Populations Of A Regionally Rare Perennial Plant Indicates The Need For Reevaluation Of Management Units, Cheyenne Moore, Angela J. Mcdonnell, Scott Schuette, Christopher T. Martine

Faculty Journal Articles

Conservation of rare species often relies on the delineation of management units and genomic tools can now be applied for this purpose. However, this is not as common on a local scale, where populations are often small and fragmented, despite the utility of informing conservation and management practice at the regional level. We use a genotyping by sequencing (GBS) approach to assess the perennial riparian plant species Baptisia australis (Fabaceae) in Pennsylvania, where the taxon is at the edge of its natural distribution and considered threatened. In this system, we investigate whether sampled subpopulations exhibit genetic structure. We find that …

Rapid Identification Of Ambystoma Mexicanum Genotype Using Pcr Techniques, Elizabeth C. Dean

Undergraduate Honors Thesis Projects

Ambystoma mexicanum is an aquatic salamander species, commonly known as the axolotl, native to Mexico that is widely researched all over the world. In the wild, these salamanders have brown/black colored skin due to the presence of melanophores and xanthophores with shiny spots due to iridophores. In captivity, however, there are multiple different color morphs (phenotypes) of axolotls including leucistic, melanistic, and copper. Melanoid axolotls have black skin made by mostly melanophores, little xanthophores, and no iridophores. Melanistic genotypes such as melanoid and wild type color morphs are thought to be controlled by a single gene called Leukocyte Tyrosine Kinase …

Examining Loss Of Imprint In F1 Hybrid Female Mice Due To X Chromosome Epimutation And The Implications For Autism, Arianna H. Roach

Honors Scholar Theses

Sex biases are prevalent among various neurodevelopmental disorders, with males experiencing them at higher frequencies or severities than females. This male bias is poorly understood, and our lab aims to elucidate this mechanism using our model of transgenerational epigenetic inheritance. Our lab identified the cluster of genes Xlr3b/4b/4c on the X chromosome that are imprinted in the female brain. Preliminary studies suggest that Xlr3 acts as a mediator molecule in our model. Xlr3 knockdown male mice exhibited significant meiocyte loss that can be attributed to Meiotic Sex Chromosome Inactivation. Their female offspring also displayed loss of imprinting of Xlr3 and …

Microbial Community And Water Quality Assessment Of Crassostrea Virginica Habitats In Southeast Florida, Stacy Brown

All HCAS Student Capstones, Theses, and Dissertations

Eastern oysters (Crassostrea virginica) are essential habitat-forming species that contribute significantly to coastal water quality due to their filter-feeding behavior. Unlike other coastal regions in the Gulf of Mexico and Northeastern United States, oysters are not commercially managed in Southeast Florida and as a result sparse data exists on locations of the Eastern oyster habitat. Similarly, the benefits of oyster reefs to water quality are also not fully documented in Southeast Florida. Although beneficial and often referred to as keystone habitat building species, populations of C. virginica are not currently listed as protected species so little work has …

The Role Of Elongin B In Drosophila Melanogaster Muscle Development, Madelyne Dayan

Student Theses and Dissertations

Muscle atrophy is a result of a number of muscle diseases, as well as aging, disuse, and infections. Muscles weakened in these ways exhibit a characteristic decrease in size, strength, and mobility. The similarities between muscle in humans and Drosophila allow for direct comparisons to be made in vertebrates from studying muscle in Drosophila. Differential gene expression has been shown to play an important role in embryonic muscle development in Drosophila melanogaster. A previous study identified Elongin B (EloB) to be involved in somatic muscle morphogenesis in Drosophila, with mutant embryos displaying severe muscle defects, including thin, mis-attached, and missing …

Competence Protein Comea And Oxidative Stress In Bacillus Subtilis Stationary Phase Mutagenesis, Angeline Roldan, Sam Schauf

Undergraduate Research Symposium Posters

Stationary Phase Mutagenesis is a process where a bacterium can accumulate mutations in the absence of cell division. This may occur via competent DNA uptake and oxidant DNA damage and repair. ComEA is a transmembrane protein in B. subtilis that is required for the transport of exogenous DNA into the cell. (Figure 1)

Pseudomonas Aeruginosa Exoy Enzymatic Activity Inhibits Exos-Induced Caspase-3/7 Activation But Not Cytotoxicity In Pmvecs, Connor Holm

Poster Presentations

Pseudomonas aeruginosa (P. aer.) is the most common cause of ventilator associated pneumonia (VAP) in ICU patients. Different combinations of exoenzymes (S, T, Y, and U) are found in P. aer. strains. ExoY is most often associated with VAP in ICU patients. ExoY infection of pulmonary microvascular endothelial cells (PMVECs) induces cell rounding but does not activate intracellular caspase-3/7 or cause cell death. ExoS and ExoT infection of epithelial cells leads to caspase-3/7 dependent cell death. Previous studies using epithelial cells show that ExoY alleviates the cytotoxic effects of ExoS and ExoT. Here, we sought to determine whether ExoY inhibits …

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

Poster Presentations

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 …

Rnai Pathway Homeostasis Is Essential For Longevity In C. Elegans., Sejal Dulal

2025 Spring Honors Capstone Projects - Archive

RNA interference (RNAi) is a gene regulatory mechanism that is conserved across all animal species, including humans and the microscopic nematode, Caenorhabditis elegans. Many studies have identified the RNAi pathway factors and dissected the regulatory mechanisms of RNAi pathways, but there is little understanding of how the RNAi pathways themselves are regulated. Previously, Rogers and Phillips identified a feedback loop mediated by a pair of small RNA sensors, Sensor of siRNAs-1 (sosi-1) and eri-6[e-f], embedded within the genomic locus of a small RNA biogenesis factor, ERI-6/7. In this feedback motif, loss of small RNA-mediated silencing of …

Elucidating The Role Of Transposable Element Derived Gene, Dplg3, In Drosophila Melanogaster, Kaisy A. Martinez

2025 Spring Honors Capstone Projects - Archive

A big fraction of most eukaryotic genomes is comprised of transposable elements (TEs). TEs are mobile genetic sequences often causing deleterious effects as they increase in copy number. On rare occasions, TEs can undergo molecular domestication, where the TE proteins are co-opted by the host to serve cellular functions. In Drosophila melanogaster, domestication from PIF/Harbinger TEs has resulted in five Drosophila PIF-Like Genes (DPLG1-4 and 8). This study focuses on investigating the function of DPLG3. In DPLG3 knock out lines, DPLG3-KO, a fraction of the progeny shows an abnormal gonad phenotype. We sought to confirm …

Uncovering The Evolutionary Origins Of Neo-Sex Chromosomes In The Insect Family Membracidae, Mary Kumah

2025 Spring Honors Capstone Projects - Archive

This research explores the evolution of the neo-XX/XY sex chromosome system of Amblyophallus exaltatus, a treehopper insect in the family Membracidae. Neo-XX/XY sex chromosome systems can evolve from an XX/X0 sex chromosome system via fusion events between the X chromosome and an autosome. Although cytological work has indicated the presence of a neo-XX/XY system within A.exaltatus, the chromosomal identity of the fused autosome and the molecular drivers behind this chromosomal fusion remain poorly understood. By performing a coverage analysis with whole genome sequence data, the parts of the A.exaltatus genome that fused with the X chromosome will be better …

Genetic Influence Of Allelic Variation On The Phenotypic Variability Of Cognitive Outcomes In Individuals With Williams Syndrome., Marinie P. Joseph

Electronic Theses and Dissertations

Williams syndrome (WS) is caused by a rare microdeletion of 25 – 27 genes on chromosome 7q11.23, characterized by a distinctive cognitive profile with considerable phenotypic heterogeneity. However, the genetic factors underlying this phenotypic variability remain unclear. I explored two genetic mechanisms—parent-of-origin (PoO) effects and genome-wide polygenic variation, as measured by polygenic scores (PGSs)—to elucidate possible influences on cognitive variability in WS. The first study examined PoO effects on cognitive abilities in two overlapping samples of children with WS (N = 211, N = 251). PoO refers to which parental homolog of chromosome 7 contains the WS deletion. Despite …

Investigation Into Mycorrhizae Associated With Native Venus' Flytrap Root Tissue, Anna Carnaggio

Electronic Theses and Dissertations

Dionaea muscipula, a plant commonly known as the Venus' flytrap, is found native to the southeast corner of North Carolina and the northeast corner of South Carolina. Several populations of native Venus' flytraps are known to exist in the nutrient-poor peat bog conditions in and around Lewis Ocean Bay Heritage Preserve (LOBHP) in Northeastern South Carolina. Anthropogenic pressures in Horry County, specifically surrounding LOBHP, have resulted in a loss of habitat for several native and endangered species. As a result, conservation efforts are focused on relocating native Venus' flytraps into adjacent habitats to ensure survival. This is only a temporary …

Perspectives On Clinical Oncogenomics: Secondary Germline Variants Associated With Tumor Genomic Profiling In Community Cancer Care And Advanced Practitioner Oncogenomic Proficiency, Sarah Moncado

All Dissertations

Precision medicine in oncology is defined by the sequencing of tumor genomic variants that can be used to identify targeted treatment for patients. Secondary pathogenic and likely pathogenic germline variants (P/LPGVs) can incidentally be detected on tumor genomic profiling (TGP). With the rise in precision medicine over the past 15 years, secondary P/LPGVs on TGP have been an increasingly important clinical issue. However, there are factors that can lead to misidentification and underreporting of P/LPGVs. Germane to this clinical practice issue is healthcare provider oncogenomic literacy and proficiency.

A scoping review was conducted to evaluate the variability of the prevalence …