Molecular Genetics Commons^™

Developing A Small Molecule To Inhibit Hsf1 Expression In Cancer And Evaluating Natural Genetic Variation In Small Molecule Toxicity., Michaela Kendal Foley

Theses and Dissertations

Each year cancer affects nearly 20 million people worldwide and genetic differences across populations can impact cancer onset and progression. Specifically, tumors with high levels of HSF1, the master regulator of the cytoprotective heat shock response (HSR), are correlated with poor patient outcomes in multiple cancers such as prostate, breast, and melanoma. Subsequently, the development of pharmacological inhibitors of HSF1 represents a promising strategy for anticancer therapeutics. Using a luciferase-based transcriptional reporter, two small molecule libraries were screened for inhibitors of HSF1 expression in human embryonic kidney cells, yielding ten compounds that decrease HSF1 expression. To identify if cancer lines …

Missense Mutation Of Msh6 Leucine 696 Has No Apparent Effect On The Dna Mismatch Repair Process, Razan H. Hammad, Rafia Rashid, Essence Tarrence, Christopher Bolden, Joanna E. Haye-Bertolozzi

XULAneXUS

Lynch Syndrome and Constitutional Mismatch Repair Deficiency are human diseases implicated in mutations of DNA mismatch repair (MMR) genes. This experiment tested a mutation of an MMR gene, MSH6, and evaluated how the mutation affected overall MMR effectiveness. Using the yeast Saccharomyces cerevisiae, we performed the CAN1 forward mutation assay to study msh6-L696F and its implications in the MMR process. We hypothesized that there would be a significant change in molecular function in the Msh6 protein in the presence of this mutation. Bioinformatic tools predicted that this amino acid change would have deleterious effects on MMR function. However, …

Hierarchical Lineage Tracing To Unravel Mechanisms Of Cancer Treatment Resistance, Rachel Danielle Saxe

Dartmouth College Ph.D Dissertations

Cancer cells adapt to treatment, leading to the emergence of clones that are more aggressive and resistant to anti-cancer therapies. We have a limited understanding of the development of treatment resistance as we lack technologies to map the evolution of cancer under the selective pressure of treatment. To address this, we developed a hierarchical, dynamic lineage tracing method called FLARE (Following Lineage Adaptation and Resistance Evolution). We use this technique to track the progression of acute myeloid leukemia (AML) cell lines through exposure to Cytarabine (AraC), a front-line treatment in AML, in vitro and in vivo. We map distinct cellular …

Crispr-Induced Mutagenesis Of Arabidopsis Thaliana Gene Apetala3, Hazel Frans, Tara Phelps-Durr

SACAD: Scholarly Activities

This project aims to create CRISPR-CAS9 mutations in the APETELA3 (AP3) gene of the model plant Arabidopsis thaliana. AP3 is a class B gene critical to the petal and stamen development of Arabidopsis flowers. AP3 is defined in a MADS domain, which binds directly to DNA and may be responsible for the expression of the CaRG-box genes. AP3 works in conjunction with PISTILLATA (PI), AGAMOUS (AG), APETALA1 (AP1), and SEPALLATA (SEP) genes to specify the development in the second and third whorls of the flower. While several alleles of AP3 already exist, these alleles are strong alleles that knockout gene …

Emerging Technologies For Forensic Genetic Identification, Lilly Llanos

Senior Honors Theses

There are many new innovations in forensic science that are being developed for the identification of biological evidence. These techniques include next-generation DNA sequencing, DNA phenotyping, and forensic genetic genealogy. This thesis will explore each, as well as newer applications of proteomics. The methodologies, reliability, practicality of cost and training, moral implications, and past research of each will be discussed. Finally, some ideas for future research and steps to drive growth and greater understanding will be suggested. This will encourage further innovations and the increased acceptance of forensic evidence in court. Each method was found to have both advantages and …

Identification Of Novel Argonaute Proteins Using A Metagenomic Mining Approach, Lobna Abdallah Ghonaim

Theses and Dissertations

Gene editing is one of the most promising tools in science. It enables precise modifications of an organism's genetic material. Metagenomics is considered a powerful tool that unlocks the broad genetic potential found in uncultured microbial communities. Exploring the genetic diversity of uncultured microbial communities helps identify novel functional proteins with unique properties and make the best use of these diverse microbial ecosystems.

We developed and employed a metagenomic-based approach to mine more than 1000 metagenomes for prokaryotic argonaute proteins (pAgos), a potential gene editing machinery encoded in bacterial and archaeal genomes. Our workflow involved strict quality control, sequence assembly, …

The Role Of Secondary And Tertiary Structure In The Cap-Independent Translation Of Fgf-9 And Hif-1-Alpha, Amanda Michelle Whittaker

Dissertations, Theses, and Capstone Projects

Under normoxic conditions, eukaryotes initiate translation of RNA through eIF4E recognition of the 5’ cap. However, under cellular stress, eukaryotic translation must be initiated through a 4E-independent, or “cap-independent” mechanism, involving eukaryotic initiation factor 4G (eIF4G) binding directly to the 5’ untranslated regions (5’ UTR) of the RNA. eIF4G binding then recruits the ribosome to the transcript. While this mechanism is useful for translation of apoptotic transcripts and transcripts involved in cell survival, cap-independent translation is also utilized by oncogenic RNA for tumorigenesis. Previous work by our lab and others has categorized this recruitment and initiation mechanism as either internal-ribosome-entry-site …

Role Of Chemotype In Aggressiveness, Toxicity, And Competitive-Ness Of Fusarium Graminearum On Wheat, Simran Goyal

Theses and Dissertations--Plant Pathology

Fusarium Head Blight (FHB) of wheat, caused by the fungus Fusarium graminearum, is a devastating disease that led to epidemics in the U.S. during the 1990s, resulting in economic losses exceeding $2.6 billion. Typical symptoms include bleached spikelets and shriveled grains, often contaminated with trichothecene mycotoxins that make them unsafe for food or feed. FHB severity and mycotoxin production are influenced by a complex interplay between host genotype, environmental factors, and pathogen genotype. Integrated management practices that include the use of more resistant cultivars, crop rotation, and fungicide applications help to reduce disease incidence and severity. Disease forecasting models …

‘Who’S Your Daddy?’: Ddradseq Parentage In Broodstock-Offspring Pairs Of Diadema Antillarum In A Population Restoration Initiative, Bianca R. Rosendahl

Undergraduate Scholarship and Creative Works

In the early 1980s Diadema antillarum, or the long-spined urchin, was hit by a catastrophic mass mortality event across the western Atlantic and Gulf of Mexico, inclusive of the Florida Keys. The cause of this die-off event was likely triggered by a pathogen or environmental stressor that decimated native populations by up to 98%. The species has not yet fully recovered and is struggling with recruitment success which is why it may benefit from an ex-situ recovery program. In this study, I used single nucleotide polymorphisms (SNPs) to identify genetic variation and analyze parentage in a captive population of …

Developing A Comprehensive Genome-Scale Metabolic Model For The Arabidopsis Thaliana Root System, Lohani Esterhuizen

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Arabidopsis thaliana (Arabidopsis) is the most well-established model plant to date. Being the first plant to have its genome mapped, studies on Arabidopsis have provided insurmountable insights into the physiological and biochemical nature of plants. Methods that allow us to computationally study the metabolism of organisms include the use of genome-scale metabolic models (GEMs). Despite its popularity, no GEM currently maps the metabolic activity in the root system of Arabidopsis, which is the first organ to face and respond to stress conditions in the soil. This work aims to develop and implement a comprehensive GEM of the Arabidopsis root system …

Genomic Data Science Approaches For Understanding Human Diseases, Snehal Shah

All Dissertations

The intricate interplay of genetic predisposition, environmental influences, and lifestyle acts as the multifactorial landscape of diseases. Understanding this complexity presents a significant challenge. Molecular insights into disease mechanisms, particularly the interactions of DNA, RNA, and proteins with environmental and lifestyle factors, have revolutionized disease diagnosis, prognosis, and treatment. High-throughput technologies, such as next-generation sequencing, generate large amounts of molecular data, holding a wealth of knowledge. These datasets unveil the roles of genes and their interactions with various factors through analysis, shedding light on previously unknown molecular mechanisms underlying disease pathogenesis. Furthermore, they facilitate the discovery of biomarkers crucial for …

Uncovering The Hidden Diversity Of Antibody Heavy Chains And Their Implications For Autoantibody Mediated Disease., Easton Earl Ford

Electronic Theses and Dissertations

Understanding the diversity of antibody (IG) molecules at the DNA and RNA level is imperative for understanding immunological processes and disease. Much of the work to uncover IG diversity has been focused on diversity in the variable region of the IG molecule which is crucial for antigen binding. However, the diversity of the constant region responsible for the functions of IG has largely been ignored in the field of immunogenetics. The work presented in this thesis challenges the dogma that the constant region is invariant in terms of genetic diversity. In this thesis we present the development of a long-read …

Leveraging The Genomic Tools To Explore The Molecular Basis Of Salinity Tolerance In Rice And Soybean, Rajat Pruthi

LSU Doctoral Dissertations

Salinity stress significantly challenges agricultural productivity, particularly affecting major crops like rice and soybean. This research investigates the genetic basis of salt tolerance in both crops through high-resolution genetic mapping, genome-wide association studies (GWAS), and RNA-Seq analysis. In rice, we examined quantitative trait loci (QTLs) associated with salt tolerance at the seedling and flowering stages using a population of advanced backcrossed introgression lines (ILs). A genetic map, constructed with 14,230 polymorphic SNP markers, identified distinct QTLs and candidate genes for salt tolerance at both stages, suggesting differential genetic controls. Notable genes such as OsHAK13 and OsCYP21-4 were upregulated under salt …

Conservation Genomic Investigation Of A Threatened Trout Species Endemic To The Gila River, David Thomas Camak

Biology ETDs

Climate change is a looming threat to the persistence of species, especially aquatic, imperiled species. Species native to desert streams are at a particular disadvantage, as many species already face drought, floods, wildfires, and threats from nonnative species, all of which are thought to be exacerbated by climate change. Species such as the threatened Gila Trout (Oncorhynchus gilae) already have small ranges and persist in fragmented and isolated habitats that limits gene flow between populations. Therefore, it is important to understand the current genomic status of such populations to be able to predict the future effects of climate …

Ocular Gene Transfer In The Spotlight: Implications Of Newspaper Content For Clinical Communications, Shelly Benjaminy, Tania M. Bubela

Office of the Provost

Background: Ocular gene transfer clinical trials are raising hopes for blindness treatments and attracting media attention. News media provide an accessible health information source for patients and the public, but are often criticized for overemphasizing benefits and underplaying risks of novel biomedical interventions. Overly optimistic portrayals of unproven interventions may influence public and patient expectations; the latter may cause patients to downplay risks and over-emphasize benefits, with implications for informed consent for clinical trials. We analyze the news media communications landscape about ocular gene transfer and make recommendations for improving communications between clinicians and potential trial participants in light of …

Omani Camels From A Cultural And Genomics Perspective, Al Muatasim Al Zadjali

Electronic Theses and Dissertations

The Dromedarian camel, Camelus dromedarius, is native to the Arabian Peninsula, including the Sultanate of Oman. These camels are used for food, milk, as well as show and racing competitions. Despite their economic and cultural importance research on camels in Oman is limited. The goal of this study was to examine their genomic variation, relationship with camels in other parts of the Arabian Peninsula, and to determine if selective breeding has led to the establishment of distinct breeds in Oman. Information was compiled from multiple sources to produce a comprehensive review on the breeding, management, economic and cultural use, …

Cis-Regulatory Mechanisms Through Stages Of Erythroid Regenration, Yichao Zhou

Theses & Dissertations

Produced by steady state erythropoiesis, erythrocytes serve as vital regulators of metabolism and life by delivering oxygen to all the cells and tissues. Under acute anemia, steady state erythropoiesis is not sufficient to produce enough erythrocytes, leading to distinct mechanisms needed to regenerate large numbers of mature erythrocytes rapidly. Erythroid regeneration occurs in four stages: activation, expansion and differentiation, resolution, and post-resolution, according to the dynamics of erythrocyte numbers and progenitor activity. Erythroid regeneration throughout this timeline requires some critical extracellular cues, but the intrinsic molecular mechanisms needed to accelerate and decelerate the activity of erythroid progenitors in anemia and …

"The Relevant History And Medical And Ethical Future Viability Of Xenotransplantation", Morgan Janes

Augustana Center for the Study of Ethics Essay Contest

Xenotransplantation, the transplantation of organs or tissues from one species to another, presents a complex nexus of medical, ethical, and cultural considerations. In this article, we delve into the multifaceted landscape of xenotransplantation, beginning with a thorough examination of its relevant historical trajectory. From early experiments to recent advancements, we chart the evolution of this field, setting the stage for a nuanced discussion. We then confront the central issue: the true medical viability of xenotransplantation and the looming specter of operative risk. By scrutinizing the ethical dilemmas inherent in xenotransplantation through a multicultural lens, we illuminate the diverse perspectives that …

Genome-Wide Crispr Screen Reveals The Synthetic Lethality Between Bcl2l1 Inhibition And Radiotherapy, Ling Yin, Xiaoding Hu, Guangsheng Pei, Mengfan Tang, You Zhou, Huimin Zhang, Min Huang, Siting Li, Jie Zhang, Citu Citu, Zhongming Zhao, Bisrat G Debeb, Xu Feng, Junjie Chen

Faculty, Staff and Student Publications

Radiation therapy (RT) is one of the most commonly used anticancer therapies. However, the landscape of cellular response to irradiation, especially to a single high-dose irradiation, remains largely unknown. In this study, we performed a whole-genome CRISPR loss-of-function screen and revealed temporal inherent and acquired responses to RT. Specifically, we found that loss of the IL1R1 pathway led to cellular resistance to RT. This is in part because of the involvement of radiation-induced IL1R1-dependent transcriptional regulation, which relies on the NF-κB pathway. Moreover, the mitochondrial anti-apoptotic pathway, particularly the BCL2L1 gene, is crucially important for cell survival after radiation. BCL2L1 …

Exploring 3d Genome Interaction And Epigenetic Regulation Via Swi/Snf Complex And Deep Learning Models, Ruoyun Wang

Dartmouth College Ph.D Dissertations

The three-dimensional organization of the genome is fundamental in regulating gene expression and maintaining cellular function. This organization's complexities, influenced by epigenetic marks and chromatin remodeling complexes, are crucial for understanding genomic regulation. Among these, the SWI/SNF complexes are key, facilitating chromatin accessibility and regulating gene activity across cell types. The first part of my dissertation focuses on SWI/SNF complexes, exploring their role in chromatin remodeling and their impact on 3D genome architecture. Utilizing next-generation sequencing (NGS) techniques, this section investigates the interplay between these complexes and chromatin structure. During my research on the SWI/SNF complex, I was intrigued by …

The Evolution Of The Metazoan Circadian Molecular Mechanism And The Conservation Of Canonical Circadian Elements, Olivia Waldridge

Theses and Dissertations--Biology

The temporal organization of biological activities through circadian rhythms is pivotal for the survival of organisms. Significant progress has been made in understanding the molecular foundations of animal circadian clocks through the characterization of key components such as Clock, Bmal1/Cycle(Cyc), Period (Per), Timeless, and Cryptochrome (Cry) in several model organisms. To determine the universality of this conservation, we investigated the sequences of these genes and their paralogs across 46 animal species that encompass multiple phyla in the metazoan kingdom to resolve the relative timing of duplication and loss events that have diversified core clock components in the metazoan kingdom. Using …

Developing Cellular Systems To Elucidate Rna Structural Dynamics Of Cag Expansion Transcripts In Spinocerebellar Ataxias, Victoria Demeo

Electronic Theses & Dissertations (2024 - present)

Spinocerebellar ataxias (SCAs) are a diverse group of over 40 genetically heterogeneous neurodegenerative disorders, many of which are caused by a trinucleotide CAG repeat expansion in the coding region of specific genes. These expansions lead to the production of polyglutamine (polyQ) tracts that interfere with normal protein function, triggering cellular dysfunction and contributing to disease pathogenesis. The most well-known of these SCAs, such as SCA1, SCA2, and SCA3, exhibit progressive neurodegeneration, yet the precise mechanisms through which these mutations cause disease remain poorly understood.

A significant challenge in studying CAG repeat expansion disorders lies in the complexity of the disease …

Chromatin Regulation By Swi/Snf Remodelers In Somatic Stem Cell Maintenance And Transformation, Luke Thomas Deary

Dartmouth College Ph.D Dissertations

Cell identity is defined by the epigenome, whereby chromatin regulators work in concert to promote gene expression programs that serve a cell’s specialized purpose. Mutations in chromatin regulators are amongst the most frequent drivers of human disease, underscoring the importance of understanding their activities in maintaining cell identity and tissue function. In particular, mutations in subunits of the evolutionarily conserved SWI/SNF chromatin remodeling complexes drive diseases across human tissues in both development and adult tissue maintenance5. Three major SWI/SNF complexes exist: BAF, PBAF, and GBAF, which differ in their composition and genomic targeting but share an ATP-dependent catalytic activity to …

Genetic Determinants Underlying The Progressive Phenotype Of Β-Lactam/Β-Lactamase Inhibitor Resistance In Escherichia Coli, William C Shropshire, Hatim Amiji, Jordan Bremer, Selvalakshmi Selvaraj Anand, Benjamin Strope, Pranoti Sahasrabhojane, Marc Gohel, Samuel Aitken, Sarah Spitznogle, Xiaowei Zhan, Jiwoong Kim, David E Greenberg, Samuel A Shelburne

Faculty, Staff and Student Publications

Currently, whole-genome sequencing (WGS) data have not shown strong concordance with Escherichia coli susceptibility profiles to the commonly used β-lactam/β-lactamase inhibitor (BL/BLI) combinations: ampicillin-sulbactam (SAM), amoxicillin-clavulanate (AMC), and piperacillin-tazobactam (TZP). Progressive resistance to these BL/BLIs in the absence of cephalosporin resistance, also known as extended-spectrum resistance to BL/BLI (ESRI), has been suggested to primarily result from increased copy numbers of bla TEM variants, which is not routinely assessed in WGS data. We sought to determine whether addition of gene amplification could improve genotype-phenotype associations through WGS analysis of 147 E. coli bacteremia isolates with increasing categories of BL/BLI non-susceptibility ranging …

Investigating The Impact Of Transcription On Mutation Rates, Sarah Patterson

Theses and Dissertations

tRNA genes are highly transcribed and perform one of the most fundamental cellular functions. Although a universal pattern observed across all three domains of life is that highly transcribed genes tend to evolve slowly, tRNA genes have been shown previously to evolve rapidly. This rapid sequence evolution could result from relaxed selection, increased mutation rate, or a combination of both. Here, we use mutation-accumulation line sequencing data to show that tRNA genes accumulate more mutations than other gene types. Our results indicate that this elevated mutation rate is a consequence of both elevated transcription-associated mutagenesis and a lack of transcription-coupled …

Increased Coding Potential Of Bovine Herpesvirus 1, Victoria Jefferson

Theses and Dissertations

Bovine respiratory disease (BRD) costs the cattle industry millions of dollars in costs in treatment and loss every year in the United States. A significant pathogen often contributes to BRD is Bovine Herpesvirus 1 (BoHV-1), a double stranded DNA virus with the ability to establish latency in the trigeminal ganglia and neurons. Primary infection with BoHV-1 results in immunosuppression that increases the risk of secondary bacterial infection and pneumonia. Because herpesviruses infect their hosts for life and can be reactivated in times of stress, BoHV-1 can present a recurring risk of BRD. The following research aims to expand the knowledge …

Structural Diversity And Stress Regulation Of The Plant Immunity-Associated Calmodulin-Binding Protein 60 (Cbp60) Family Of Transcription Factors In Solanum Lycopersicum (Tomato), Vanessa Shivnauth, Sonya Pretheepkumar, Eric J. R. Marchetta, Christina A. M. Rossi, Keaun Amani, Christian Castroverde

Biology Faculty Publications

Cellular signaling generates calcium (Ca2+) ions, which are ubiquitous secondary messengers decoded by calcium-dependent protein kinases, calcineurins, calreticulin, calmodulins (CAMs), and CAM-binding proteins. Previous studies in the model plant Arabidopsis thaliana have shown the critical roles of the CAM-BINDING PROTEIN 60 (CBP60) protein family in plant growth, stress responses, and immunity. Certain CBP60 factors can regulate plant immune responses, like pattern-triggered immunity, effector-triggered immunity, and synthesis of major plant immune-activating metabolites salicylic acid (SA) and N-hydroxypipecolic acid (NHP). Although homologous CBP60 sequences have been identified in the plant kingdom, their function and regulation in most species remain unclear. In …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Unique Transcriptional Profiles Underlie Osteosarcomagenesis Driven By Different P53 Mutants, Dhruv Chachad

Dissertations and Theses (Open Access)

Missense mutations in the DNA binding domain of the Trp53 gene are characterized as structural (p53R172H) or contact (p53R245W) mutations based on their effect on the conformation of the protein. These mutations show gain-of-function activities such as increased metastatic incidence as compared to p53 loss, often mediated by their interaction with a repertoire of transcription factors. These interactions are largely context specific. In order to understand the mechanisms by which these mutations drive osteosarcoma progression, we created a mouse model, wherein either the p53 structural mutant p53R172H, or the contact mutant, p53R245W, are expressed specifically in …

Intellectual Disability Related To De Novo Germline Loss Of The Distal End Of The P-Arm Of Chromosome 17: A Case Report, Eden Pope, Matthew Huertas, Amar Paul, Braden Cunningham, Matthew Jennings, Ryan Perry, Stephanie Chavez, John A. Kriak, Kyle B. Bills, David W. Sant

Annual Research Symposium

Hypothesis/Purpose: In this report we present a case of a 20-year-old female with congenital intellectual disability, stunted growth, and hypothyroidism. Competitive genetic hybridization (CHG) revealed a loss of 17p13.3, and the deletion was not present in either parent. This deletion has not previously been characterized, but mutations on the p-arm of chromosome 17 are responsible for Miller-Dieker Syndrome and Isolated Lissencephaly Sequence, both of which share symptoms in common with the patient.

Methods: Peripheral mononuclear cells (PBMCs) were used for karyotyping and competitive genetic hybridization (CHG). Bioinformatic analysis was carried out using the Genome Data Viewer (ncbi.nlm.nih.gov/genome/gdv).

Results: Karyotype was …