Genomics Commons^™

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 …

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 …

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 …

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 …

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 …

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 …

A Stakeholder-Informed Conceptual Framework For Evaluating Genomics In Precision Oncology, Julie A. Wiedower

All Dissertations

This dissertation explores the value of genomic testing in precision oncology with an emphasis on how US payers conceptualize and prioritize elements of value. This research aims to address gaps in understanding payer perspectives and proposes a stakeholder-informed framework for evaluating genomic testing in oncology. To achieve this aim, the presented research investigates payer perspectives, value-based cancer care priorities, and the conceptual understanding of the value of a genetic diagnosis to establish a framework for value with the payer audience in mind. Chapter 1 outlines relevant background information relating to the genomic revolution and challenges in translating genomic testing technologies …

The Genomic Landscape And Prognostic Impact Of Kras, Stk11, And Smarca4 Mutations And Co-Mutations On Survival Outcomes In Non-Small Cell Lung Cancer, Peter Manolakos

All Dissertations

Non-small lung cancer (NSCLC) accounts for 85% of lung cancer cases, and Kirsten rat sarcoma viral oncogene homolog (KRAS), Serine/Threonine Kinase 11 (STK11), and SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4 (SMARCA4) mutations and co-mutations have been increasingly recognized for their potential prognostic significance. However, clear knowledge gaps remain regarding which treatments should be selected for patients who present clinically with KRAS/STK11 or KRAS/SMARCA4 co-mutations, as outlined in Chapter 1. Despite significant clinical development advancements in immunotherapy and targeted therapy, a deeper understanding of the influence of these genomic …

Investigating Genetic Regulators Of Crystal Cell Development In Drosophila Melanogaster, Andrea Feria, Nyla Walbrook, Anisa Turaeva, Rebecca Spokony

Publications and Research

Crystal cells, a subset of Drosophila melanogaster hemocytes, are important for melanization, a crucial immune response. While the genetic regulation of crystal cell develop remains incompletely understood, this study investigates the functions of five candidate genes: ACXB, ACXA, Gp210, CG4390, and Cyp4s3; identidied through previous genome-wide association studies. Using the Gal4/UAS system along with RNA interference (RNAi), we exclusively knocked down each gene in third instar larvae and quantified crystal cell populations following heat shock-induced melanization. Our results imply that the knockdown of ACXB and ACXA significantly increased crystal cell counts in both sexes, suggesting these genes either act as …

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, …

Genome Analysis Of Aeromonas Hydrophila Strain S14-452, Zarin Tasnim Raya

Undergraduate Research Conference

The Aeromonas hydrophila are gram-negative, opportunistic bacteria that can infect many groups of organisms, mainly fish and amphibians. In channel catfish, A. hydrophila causes fatal bacterial septicemia, leading to massive economic losses for catfish farmers. Therefore, an understanding of its genome will aid in identifying its virulence factors, metabolic pathways and survival mechanisms within the host. This study details the draft genome sequence of A. hydrophila strain S14-452, isolated from channel catfish exhibiting bacterial septicemia during a disease outbreak at a catfish farm.

A. hydrophila strain S14-452 was sequenced using the Illumina iSeq 100 System. Assembly was performed with SPAdes, …

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 …

Analysis Of Chromatin Accessibility Changes In Endothelial Cells Exposed To Plastic Contaminants, Mikhail Y. Salnikov, Carly Boye, David B. Witonsky, Gabrielle Garlicki, Adnan Alazizi, Francesca Luca, Roger Pique-Regi

Medical Student Research Symposium

Degradation products from everyday plastic products are known to bioaccumulate and have also been shown to contaminate drinking water and food sources. BPA and phthalates are endocrine disrupting chemicals and plastic components that have previously been associated with endothelial cell dysfunction, atherosclerotic and other adverse cardiovascular events. However, there is a limited understanding of the mechanisms underlying these associations, such as genome-wide chromatin accessibility changes in endothelial cells exposed to these compounds. The purpose of this study is to explore genome-wide changes in chromatin accessibility associated with plastic exposure, as well as the discovery of transcription factor binding motifs dysregulated …

Differential Gene Coexpression In 16p11.2 Autism Spectrum Disorder, Joseph Patacsil

Senior Theses

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that has been associated with several genetic factors. One of these factors is a mutation of the 16p11.2 region on chromosome 16, in which both deletions and duplications have been strongly associated with ASD. KCTD13 is a gene in the 16p11.2 gene locus that has recently been shown to influence brain development and is also associated with ASD. This study analyzes the differential gene expression and gene pathways of these different phenotypes. KCTD13 deletion had a significant up-regulation effect on genes and shares similar pathways to the 16p11.2 duplication mutation. Mutations in …

Differential Impacts On Proteoglycan Expression In The Response To Lens Wounding In Reparative And Pro-Fibrotic Microenvironments, Janice L Walker, A. Sue Menko

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Ex vivo lens epithelial explant cultures created through a technique that mimics cataract surgery provided an ideal model with which to compare the impacts on proteoglycan expression in the response to wounding in both reparative promoting and pro-fibrotic microenvironments. On their native basement membrane capsule the injured lens epithelium undergoes regenerative repair, with the wound closing within a few days. Their migration across the wound area is led by a population of activated lens resident immune cells. The same leader cell population also directs the wounded epithelium to migrate off the outside edges of the lens explant across the surrounding …

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 …

Screening For Penicillin G Acylase (Pga)-Producing Bacteria And Gene Cloning Using Degenerate Oligonucleotide Primed-Pcr, Masdalifah Masdalifah, Sri Rezeki Wulandari, Gabriela Christy Sabbathini, Maria Ulfah, Dini Achnafani, Ahmad Wibisana, Feronika Heppy Sriherfyna, Is Helianti, Niknik Nurhayati

Makara Journal of Science

The growing concern over antibiotic resistance has driven global efforts to explore innovative solutions, including the use of Penicillin G acylase (PGA) to produce semisynthetic β-lactam antibiotics. This study screened four potential in-tracellular PGA-producing bacteria: Alcaligenes faecalis InaCC B444 (AfPGA), Kluyvera cryocrescens InaCC B850 (KcPGA), Providencia rettgeri InaCC B25 (Pr25PGA), and P. rettgeri InaCC B466 (Pr466PGA). Penicillin G Acylase encoding genes (pgas) were isolated from them using a Degenerate Oligonucleotide Primed-PCR (DOP-PCR) approach and sequenced. Microbiological assays confirmed all tested crude extracts to exhibit inhibitory effects. Penicillin G was used for evaluating hydrolytic activity and 6-Amino Penicillanic Acid (6-APA) coupled …

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 …

Antibiotic Resistome, Mobile Genetic Elements, And Virulence Profile Of Multidrug-Resistant Enterobacteriaceae Isolated From Healthy Philippine Native Chicken As Revealed By Analysis Of Whole Genome Sequence, Alvin P. Jimenez, Grignard James R. Buday, Rina B. Opulencia

The Philippine Agricultural Scientist

Gram-negative bacteria, particularly Enterobacteriaceae, acquire antibiotic resistance via horizontal transmission of resistance genes in poultry farms that give rise to multidrug-resistant (MDR) strains. The presence of MDR strains that are potentially pathogenic and zoonotic poses a concern to animal and human health. The aims of this study were to isolate MDR, potentially pathogenic Enterobacteriaceae from Philippine native chicken (PNC) and to analyze the genome of a representative MDR isolate to gain insights into the mechanisms, acquisition, and transmissibility of antibiotic resistance genes (ARGs). Cloacal swabs from PNC were used to isolate putative Salmonella that were then tested for antimicrobial …

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, …