Genetics and Genomics Commons^™

Combination Therapy With Trastuzumab And Niraparib: Quantifying Early Proliferative Alterations In Her2+ Breast Cancer Models, Ameer Mansur, Patrick N. Song, Yun Lu, Andrew C. Burns, Luke Sligh, Eddy S. Yang, Anna G. Sorace

Markey Cancer Center Faculty Publications

HER2–targeted treatments have improved survival rates in HER2+ breast cancer patients, yet poor responsiveness remains a major clinical obstacle. Recently, HER2+ breast cancer cells, both resistant and responsive to HER2–targeted therapies, have demonstrated sensitivity to poly–(ADP– ribose) polymerase (PARP) inhibition, independent of DNA repair deficiencies. This study seeks to describe biological factors that precede cell viability changes in response to the combination of trastuzumab and PARP inhibition. Treatment response was evaluated in HER2+ and HER2– breast cancer cells. Further, we evaluated the utility of 3′–Deoxy–3′–[18F]–fluorothymidine positron emission tomography ([18F]FLT–PET) imaging for early response assessment in a HER2+ patient derived xenograft …

Mapping The Sos204 ( Suppressor Of Sunn-1 204) Gene In Medicago Truncatula, Rakshya Shah

All Theses

Nodules in legumes allow the plant to form a symbiotic interaction with bacteria, providing access to the inert N₂ in the atmosphere. The Autoregulation of Nodulation Pathway (AON), a negative regulatory feedback mechanism, is a long-distance signaling system which controls the nodule numbers formed on roots, helping the plant conserve energy by not hosting bacterial symbionts beyond those needed by the plant. A forward genetic screen of the EMS mutagenized supernodulating sunn-1 mutant, a weak allele of SUNN in Medicago truncatula, identified 6 lines of heritable suppressor mutants that reduced the nodulating phenotype from supernodulating to wild-type. We used …

Integrating Omim And Intact Data For The Analysis Of Gene-Phenotype Interactions In Complex Diseases: A Linux-Based Computational Tool For Network Analysis, Devin Keane

All Theses

The field of genetics is constantly evolving. New advances in bioinformatics and computational approaches are leading to exciting new developments in our ability to treat and prevent diseases. Computational genetics provides valuable insights into the complex mechanisms and layers of biological communication that shape an organism's phenotype. Understanding these mechanisms is critical to advancing human health.

The study of diseases in genetics requires a comprehensive understanding of the interactions between various biological processes, including gene expression, protein synthesis, RNA, metabolism, and cell-cell communication. To effectively address the root causes of such diseases, multi-disciplinary approaches that integrate information from different levels …

A Dna-Peptide Crosslink (Dpc) Increases Mutagenicity In Sos-Induced Escherichia Coli, Alessandra Bassani

Honors Scholar Theses

Bacteria, such as Escherichia coli, have an inducible system in response to DNA damage termed the SOS response. This system is activated when the replicative DNA polymerase (Pol) III encounters a lesion, uncouples from DNA helicase, and single-stranded DNA (ssDNA) accumulates at the replication fork. In this study, we investigated DNA-peptide crosslink (DpC), a common lesion that results from cross-linking of proteins or peptides, UV irradiation, and alkylating agents. To increase survival following formation of a lesion, the SOS response can utilize homologous recombination, translesion synthesis (TLS), or excision repair. With TLS, the levels of DNA Pol II, IV, …

Gene Expression Changes Linked To Phenylpropanoid-Based Resistance To Fusarium Head Blight Of Wheat, Shiv Singla

Department of Plant Pathology: Dissertations, Theses, and Student Research

Fusarium graminearum is a devastating pathogen of wheat that causes Fusarium head blight (FHB) and contaminates the grain with the mycotoxin deoxynivalenol (DON). Resistance to FHB is quantitative and it is important to identify additional genes conferring resistance against it. The goal of this thesis was to examine if the constitutive expression of two sorghum phenylpropanoid pathway genes, SbCCoAOMT (encoding caffeoyl-CoA O-methyltransferase) and SbC3’H (encoding p-coumarate 3-hydroxylase), in the moderately-susceptible spring wheat CB037 can provide Type-I and Type-II resistance to F. graminearum and determine the underlying mechanisms of the enhanced resistance. The constitutive expression lines (CCoAOMT413, CCoAOMT421, C3H112, …

A Review Of How Bioinformatics And Genome Sequencing Are Affecting Precision Medicine, Taylor S. Hickey

Honors Program: Senior Projects (Public)

Advancement in genomic sequencing and bioinformatics methods have been affecting biomedical research through precision medicine, especially in the area of cancer. Vaccine therapies can be developed using neoantigens that target specific mutations in tumors. The goals of this research are to identify mutations that lead to cancer and then define subpopulations in which patients can easily be identified. The future goal is to have targeted vaccines that are specific to each subpopulation ready to be used in treatment of their cancer. Limitations to reaching these goals have been due to tumor heterogeneity, cancer location, and difficulty in creating neoantigens for …

Sequence Analysis Of Herbicide Target Genes In Herbicide-Tolerant Rice, Jonathan Kearney, Nilda R. Burgos, Gulab D. Rangani

Biological Sciences Undergraduate Honors Theses

The tolerance of mutagenized rice (Oryza sativa) lines to selector herbicides was investigated and the sequence of ALS gene was analyzed in plants that survived treatment with 4x the label rate of imazethapyr herbicide. This was done to determine if insensitivity to imazethapyr is due to mutation(s) in the herbicide binding site. Seedlots previously treated with ethyl-methyl sulfonate were planted in the field and 3-leaf seedlings were treated with various herbicides to screen for herbicide-tolerant mutants. Seeds from survivors composed the rice lines tested in the current research. Seeds were planted in the greenhouse and 3-leaf seedlings were …

Molar Macrowear As A Proxy For Age In A Captive Sample Of Papio Hamadryas, Lauren Conrad

Biological Sciences Undergraduate Honors Theses

This study is methods-focused, centering around molar crown macrowear and its performance as a proxy for age in a sample of pedigreed, non-human primates. It analyzes the correlation between age-structured variables and molar wear among both males and females in a captive group of baboons. Here, I examined whether wear is significantly correlated with age-related variables (i.e., generations/cohorts) and whether the structure of the “age” dataset differed across wear categories. Because chronological age is unknown, I used documented pedigrees and parent-offspring relationships to group individuals into possible generations. I then used dental development charts to group individuals into cohorts based …

Spatial Metabolomics Reveals Glycogen As An Actionable Target For Pulmonary Fibrosis, Lindsey R. Conroy, Harrison A. Clarke, Derek B. Allison, Samuel Santos Valenca, Qi Sun, Tara R. Hawkinson, Lyndsay E. A. Young, Juanita E. Ferreira, Autumn V. Hammonds, Jaclyn B. Dunne, Robert J. Mcdonald, Kimberly J. Absher, Brittany Dong, Ronald C. Bruntz, Kia H. Markussen, Jelena A. Juras, Warren J. Alilain, Jinze Liu, Matthew S. Gentry, Peggi M. Angel, Christopher M. Waters, Ramon C. Sun

Saha Cardiovascular Research Center Faculty Publications

Matrix assisted laser desorption/ionization imaging has greatly improved our understanding of spatial biology, however a robust bioinformatic pipeline for data analysis is lacking. Here, we demonstrate the application of high- dimensionality reduction/spatial clustering and histopathological annotation of matrix assisted laser desorption/ionization imaging datasets to assess tissue metabolic heterogeneity in human lung diseases. Using metabolic features identified from this pipeline, we hypothesize that metabolic channeling between glycogen and N-linked glycans is a critical metabolic process favoring pulmonary fibrosis progression. To test our hypothesis, we induced pulmonary fibrosis in two different mouse models with lysosomal glycogen utilization deficiency. Both mouse models displayed …

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 …

Comprehensive Long- And Short- Read Sequencing Approaches To Screen The Mutational Landscape After Therapeutic Crispr-Editing For Duchenne Muscular Dystrophy, Mary Jia, Made Harumi Padmaswari, Landon Burcham, Shilpi Agrawal, Alexis Ivy, Abbey Bryan, Christopher E. Nelson

Biomedical Engineering Undergraduate Honors Theses

Duchenne muscular dystrophy (DMD) is an X-linked muscle wasting disease caused by mutations in the Dmd gene resulting in non-functional dystrophin. Adeno-associated virus (AAV)-mediated delivery of classical CRISPR systems resulting in double-stranded breaks (DSBs) has yielded promise as a curative DMD therapeutic. However, the consequences of AAV-CRISPR require more thorough characterization. PCR-enriched short-read amplicon sequencing at cut sites is the most common method of sequencing CRISPR editing, but PCR bias results in unreliable quantification of on-target edits. We analyze orthogonal long- and short-read sequencing approaches to screen the outcomes of CRISPR technologies at the DNA and RNA-level for DMD. We …

Understanding The Role Of Heterodisulfide Reductase During Nitrogen Fixation By Methanosarcina Acetivorans, Grant Shelnut

Biological Sciences Undergraduate Honors Theses

Methanosarcina acetivorans is a methanogenic archaeon (methanogen) that is important for several processes in our biosphere. A feature of interest within this methanogen is the enzyme nitrogenase which catalyzes the reduction of unusable dinitrogen gas (N₂) into a usable form of nitrogen, ammonia (NH₃). How electrons are transferred within M. acetivorans to nitrogenase during N₂ reduction is unknown. Heterodisulfide reductase (Hdr) is a key enzyme known to reduce the electron carrier protein ferredoxin, which is a direct electron donor to nitrogenase in bacteria. I hypothesized that cytoplasmic HdrA2B2C2 functions in electron transfer to nitrogenase and …

Understanding The Relationship Between B Chromosomes And Nondisjunction In Drosophila Melanogaster, Ayushi Patel

Honors Scholar Theses

B chromosomes are supernumerary, heterochromatic genetic elements that are found in hundreds of different plant and animal species. Recently, B chromosomes were discovered in a stock of Drosophila melanogaster and are carried at a high copy number of 10-12 B chromosomes per cell. B chromosomes are not known to carry any active genes, but when placed in a wild-type genetic background, they cause a significant increase in the frequency of chromosome 4 missegregation during meiosis. This project aimed to understand the relationship between a female’s B chromosome copy number and how often she passes on too many (or too few) …

Urbanization Affects Web Abundance And Aggregation Of A Funnel‑Weaving Spider, Agelenopsis Pennsylvanica (Agelenidae), Brandi J. Pessman, Madison Hays, Earl Agpawa, Eileen Hebets

Eileen Hebets Publications

Animals distribute themselves within habitats based on a variety of environmental conditions, including those impacted by urbanization. Suspected global declines in urban arthropod biodiversity have required that we examine how urban conditions affect the distribution of this ecologically important group. Throughout North America, funnel-weaving spiders (Agelenidae) are prevalent across urban habitats and actively choose sites to build webs. We compared Agelenopsis pennsylvanica abundance and distribution between two distinct urban habitats: an urban center (university campus) and an urban forest (city park). These urban habitats differed significantly in features like plant diversity and proximity to roads and highways. We searched along …

P53 Dimers Elicit Unique Tumor Suppressive Activities Through An Altered Metabolic Program, Jovanka Gencel-Augusto

Dissertations and Theses (Open Access)

p53 is the most frequently mutated tumor suppressor in human cancer. As a tetrameric transcription factor, mutation of the p53 Tetramerization Domain (TD) is a mechanism by which cancers abrogate wild-type (WT) p53 function. p53 TD mutations result in a protein that preferentially forms monomers or dimers. These are also normal p53 states under basal cellular conditions. Although it is accepted that tetrameric p53 is required for full tumor suppressive activities, the physiological relevance of monomeric and dimeric states of p53 is not well understood. We have established in vivo models for monomeric and dimeric p53 which model Li-Fraumeni Syndrome …

Reconstructing Mutational Lineages In Breast Cancer By Multi-Patient-Targeted Single Cell Dna Sequencing, Jake Leighton

Dissertations and Theses (Open Access)

Triple negative breast cancer (TNBC) is an aggressive subtype of breast cancer with high rates of metastasis and recurrence, where TNBC patients have a poor 5-year survival and ~50% are non-responsive to chemotherapy. Aneuploidy is a cancer hallmark that is pervasive in over 90% of breast cancer patients and is indicative of complex genomic rearrangements that are acquired during tumor initiation. Although copy number aberrations have been extensively studied in relation to aneuploidy and TNBC initiation, little is currently known regarding the timing and impact of single nucleotide variants (SNVs) contributing to these early transformative genomic events. Paramount to novel …

The Diagnostic Odyssey Of Hypermobile Eds Patients: Diagnosis, Clinical Expectations, And Psychosocial Concerns, Madeline Alpar

Dissertations and Theses (Open Access)

Background: Ehlers-Danlos syndrome (EDS) is a highly variable, heritable connective tissue disorder. Hypermobile EDS (hEDS) is the most common subtype of EDS and has no identifiable underlying genetic etiology. Patients with clinical features of hEDS face a long diagnostic odyssey due to lack of genetic testing and wide clinical heterogeneity. Additionally, recent research has shown that genetic institutions limit evaluations for suspected hEDS, adding another barrier to care.

Methods: We developed an online patient survey to explore the diagnostic odyssey of hEDS for those who were diagnosed with or suspicious for hEDS. This survey included sections on demographics, diagnostic information …

Targeting Metabolic Alterations Associated With Smooth Muscle Α-Actin Pathogenic Variant Attenuates Moyamoya-Like Cerebrovascular Disease, Anita Kaw

Dissertations and Theses (Open Access)

Heterozygous pathogenic variants in ACTA2, encoding smooth muscle α-actin (α-SMA), predispose to thoracic aortic aneurysms and dissections. De novo missense variants disrupting ACTA2 arginine 179 (p.Arg179) cause a multisystemic disease termed smooth muscle dysfunction syndrome (SMDS), which is characterized by early onset thoracic aortic disease and moyamoya disease-like (MMD) cerebrovascular disease. The MMD-like cerebrovascular disease in SMDS patients is marked by bilateral steno-occlusive lesions in the distal internal carotid arteries (ICAs) and their branches. To study the molecular mechanisms that underlie the ACTA2 p.Arg179 variants, a smooth muscle-specific Cre-lox knock-in mouse model of the heterozygous Acta2 R179C variant, termed …

Deephtlv: A Deep Learning Framework For Detecting Human T-Lymphotrophic Virus 1 Integration Sites, Johnathan Jia, Johnathan Jia

Dissertations and Theses (Open Access)

In the 1980s, researchers found the first human oncogenic retrovirus called human T-lymphotrophic virus type 1 (HTLV-1). Since then, HTLV-1 has been identified as the causative agent behind several diseases such as adult T-cell leukemia/lymphoma (ATL) and a HTLV-1 associated myelopathy or tropical spastic paraparesis (HAM/TSP). As part of its normal replication cycle, the genome is converted into DNA and integrated into the genome. With several hundreds to thousands of unique viral integration sites (VISs) distributed with indeterminate preference throughout the genome, detection of HTLV-1 VISs is a challenging task. Experimental studies typically use molecular biology …

Regulation Of De Novo And Maintenance Dna Methylation By Dnmt3a And Dnmt3b, Yang Zeng

Dissertations and Theses (Open Access)

DNA methylation (5-methylcytosine, 5mC) is essential for the regulation of gene expression and integrity of the mammalian genome. It occurs predominantly in the context of CpG dinucleotides to form a symmetrical pattern on both DNA strands, which allows DNA methylation patterns to be semi-conservatively maintained during DNA replication. There are two classes of DNA methyltransferases (DNMTs): DNMT3A and DNMT3B function primarily as de novo methyltransferases that establish DNA methylation patterns, whereas DNMT1 is the major enzyme responsible for maintaining DNA methylation patterns by converting hemi-methylated CpGs to fully methylated CpGs during DNA replication. Two accessory factors also play critical regulatory …