Cell Biology Commons^™

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 …

Reconstruction Of Fox Transcription Factor-Regulated Subnetworks Mediating Cardiac Progenitor Cell Divisions, Md Rezaul Hasan

All-Inclusive List of Electronic Theses and Dissertations

Congenital heart disease (CHD) is the most common congenital anomaly worldwide, affecting approximately 1% of live births, corresponding to 1.35 million infants born with CHD each year, and remains a leading cause of infant mortality; therefore, it is urgent to understand the genetic and molecular mechanisms underlying CHD for advancing early diagnosis and treatment. Because many aspects of the Drosophila heart formation are highly reminiscent of vertebrate heart development, Drosophila melanogaster serves as a simple yet powerful model system for studying cardiac development and CHD. While at least eight Forkhead box (Fox) transcription factors (TFs) are required for proper cardiac …

Analysis Of Developmental Cardiogenic Processes Mediated By Fox And Zinc-Finger Transcription Factors, Rajnandani Katariya

All-Inclusive List of Electronic Theses and Dissertations

Cardiogenesis is a highly choreographed biological process requiring the precise integration of gene regulatory networks to govern cell division, fate determination, and spatial positioning. Disruptions in these mechanisms lead to congenital heart defects (CHDs), which affect approximately 1% of live births globally. Due to the evolutionary conservation of cardiac signaling pathways and the structural homologies between the Drosophila dorsal vessel and the early vertebrate heart tube, Drosophila melanogaster serves as a powerful model for dissecting the fundamental mechanisms of heart development. This dissertation investigates the molecular orchestration of cardiac development, specifically focusing on the roles of the transcription factors Jumu …

The Impact Of Glucose Exposure On Organic Cation Transporters (Oct) Function In A Corneal Epithelial Cell Line, David A. Garza

Theses & Dissertations

Organic cation transporters (OCT) facilitate the movement of neurochemicals and medications, contribute to the removal of cellular waste, and facilitate neuronal communication. Three subtypes of these high-capacity, low-affinity transporters (OCT1, OCT2, and OCT3) are differently expressed in peripheral tissues such as the liver, kidneys, as well as the central nervous system. OCTs are also expressed in ocular tissues. Chronic hyperglycemia is a complication commonly associated with diabetes that can lead to ocular diseases such as diabetic keratopathy, which affects the cornea. In this project, we expose immortalized human corneal epithelial cells (HCE-S) to various glucose concentrations to study their impact …

Inosine Accelerates Cancer Cell Killing By The Experimental Antifolate Ucp1162: Implications For Novel Combination Treatments, Reshma Ramesh, Charles Giardina, Alan Kuo

Honors Scholar Theses

Antifolates disrupt one-carbon metabolism (OCM), which stops nucleotide synthesis and therefore slows down cell proliferation. Our experimental antifolate, UCP1162, stops de novo purine synthesis and thymidine synthesis by targeting the OCM pathway. We investigated whether the downstream metabolites of OCM pathway: methionine, thymidine, and inosine, affect the cell death caused by UCP1162 using MV4-11 leukemia cells. Thymidine was found to partially rescue MV4-11 cells from UCP1162, in contrast, inosine was found to accelerate the cell death caused by UCP1162. These cytotoxic effects of UCP1162 alone and in combination with inosine were irreversible, as removal of treatment did not restore cell …

Reversible, Light-Controlled Inhibition Of Stim1-Mediated Calcium Signaling Using Photoswitchable Ml-9 Derivatives In Jurkat-Lucia Nfat Reporter T Cells, José L. Matute Gálvez

Honors Scholar Theses

Store-operated calcium entry (SOCE) through calcium release-activated

calcium (CRAC) channels is the dominant pathway for sustained Ca2+ influx in

non-excitable cells and is essential for T cell activation, driving downstream

signaling through the calcineurin-NFAT transcriptional axis. Dysregulation of

SOCE produces multi-systemic disease phenotypes, establishing that precise,

spatiotemporally controlled modulation of this pathway is a fundamental

therapeutic requirement. ML-9 is one of the only characterized small molecules

capable of targeting SOCE upstream at the level of STIM1 localization, but lacks

the selectivity, pharmacokinetic properties, and spatiotemporal control necessary

for therapeutic development.

This work describes the design, synthesis, and biological evaluation of …

Effects Of M6a Dna Methylation By Bacterial Methyltransferase In Colorectal Cancer, Fabian Alejandro Mendoza Galvan

Dissertations and Theses (Open Access)

Effects of m6A DNA methylation by bacterial methyltransferase in colorectal cancer Fabian Alejandro Mendoza Galvan Advisory Professor: Angela H. Ting, Ph.D. Fusobacterium nucleatum animalis (Fna) is found in the human oral cavity and gut. A distinct clade of Fna is primarily enriched in the tumor microenvironment (TME) and within colorectal cancer (CRC) cells. This clade DNA methylation pattern is primarily catalyzed by a cell-cycle regulated methyltransferase (CcrM) ortholog, M.FnI, that targets the GANTC sequence motif through methyl-6-Adenine (m6A) DNA methylation. We hypothesized that M.FnI enzyme can induce m6A methylation abnormalities in CRC cells to promote cancer progression. Evidence for endogenous …

From Antigen Presentation To Tumor Control: Mechanisms Of Type I Conventional Dendritic Cell-Based Cancer Vaccines, Josue E. Pineda

Dissertations and Theses (Open Access)

Type 1 conventional dendritic cells (cDC1s) are important for generating and sustaining antitumor immunity. Accordingly, the abundance of cDC1s in human tumors correlates with improved outcomes in cancer. Capitalizing on this role, we previously demonstrated that vaccination with in vitro-derived murine cDC1s elicits durable tumor control in multiple preclinical models; however, the immunological mechanisms underlying the efficacy of cDC1 vaccination remain unclear. Here, we examined whether in vitro-derived cDC1s resemble tumor-infiltrating DC populations and whether MHC-I and MHC-II antigen presentation contribute to cDC1-mediated tumor control following vaccination in melanoma.

As expected, MHC-I- or MHC-II-deficiency had minimal impact on …

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 …

Assessing The Use Of Exon-Skipping Morpholino Antisense Oligonucleotides Targeting The Different Sumo Paralogs As Enhancers Of The Antitumor Activity Of Chemotherapeutic Agents, Andrea Teresa Garcia-Morin

Open Access Theses & Dissertations

Post-translational modifications (PTMs) are critical regulators of protein function, stability, and localization, with SUMOylation emerging as a key modulator of cellular stress response and survival in cancer. Non-small cell lung cancer (NSCLC) is characterized by heightened dependence on SUMOylation to sustain pro-survival signaling, DNA repair, and resistance to chemotherapy. This dissertation investigates a novel chemosensitization strategy based on the splice-switching of SUMO transcripts in NSCLC cells using exon-skipping morpholinos (ESMs), which redirect splicing toward non-conjugatable SUMO alpha isoforms, thereby reducing global SUMOylation. We hypothesized that decreasing global SUMOylation through forced alternative splicing of SUMO transcripts would impair the stress-protective functions …

Novel Roles Of G-Beta-Gamma Signaling In Microtubule Dynamics And Neurodegeneration, Diana I. Olivas

Open Access Theses & Dissertations

Neurodegenerative disorders (NDDs), including Alzheimer's disease (AD), are characterized by progressive neuronal dysfunction, cytoskeletal disruption, and cognitive decline. Although Tau hyperphosphorylation and neurofibrillary tangle (NFT) formation are classical hallmarks of AD, emerging evidence suggests that microtubule (MT) dysfunction may precede and occur independently of Tau pathology. Understanding upstream regulators of MT dynamics is therefore critical for elucidating early mechanisms of neurodegeneration. Previous work from our laboratory demonstrated that G protein βγ (Gβγ) subunits directly interact with tubulin and promote MT assembly. However, the mechanism of Gβγ signaling in neuronal cytoskeletal stability and neurodegeneration remained poorly understood. The present study investigated …

Mechanistic Insights Into Enterolactone-Mediated Glut4-Dependent Glucose Uptake, Merritt Smith

Senior Honors Theses

Type 2 diabetes mellitus (T2D) is one of the leading causes of morbidity and mortality in the United States, with approximately 25% of healthcare expenditures directed toward its management and associated metabolic complications. In response to the urgent need for novel therapeutic strategies, recent research has focused on bioactive compounds derived from dietary sources. In light of that, we identified the plant lignan matairesinol (MA) and its gut-derived metabolite, enterolactone (ENL), as agents capable of enhancing glucose uptake in 3T3-L1 differentiated adipocytes. These results suggest that enterolactone may represent a promising dietary supplement for improving glycemic control in patients with …

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 Disease To Pregnancy: Rethinking Cardiac Remodeling Through Fibroblast, Immune Cell, And Hormonal Interactions, Emily B. Ruggiero, Wayne Carver, Daping Fan, Edoe C. Goldsmith

Cell Biology and Anatomy Faculty Publications

Cardiac fibrosis is a central determinant of heart failure progression and arises from pathological remodeling characterized by fibroblast activation, myofibroblast differentiation, and excessive extracellular matrix deposition. In contrast, physiological remodeling permits adaptive cardiac growth without net fibrosis. Pregnancy represents an underexplored physiological model of reversible cardiac remodeling. In response to hemodynamic load, the maternal heart undergoes hypertrophic growth that resolves postpartum, constituting a natural paradigm of fibrosis-resistant cardiac adaptation. Pregnancy and lactation are accompanied by profound endocrine and immune reprogramming of maternal tissues. We propose that this hormonal milieu orchestrates coordinated crosstalk among endothelial cells, fibroblasts, and immune cell populations …

Quantification Of Mouse Tracheal Epithelial Cell Differentiation With Cilia Defects, Olivia V. Allen

Honors Thesis

Primary Ciliary Dyskinesia (PCD) is an autosomal recessive disorder that affects 1 in every 7,500 live births. PCD results from motile cilia defects, impairing mucociliary clearance and causing chronic respiratory infections. Our lab studies include three PCD mouse lines — bgh (Spef2), nm1054 (Cfap221), and Cfap54^gt/gt (Cfap54). Prior transcriptomic data led us to hypothesize that PCD mutant mouse tracheal epithelial cells (MTECs) exhibit reduced differentiation into ciliated cells. MTECs from the trachea of the Wild Type (WT) and the PCD mutant mouse lines were cultured at an Air Liquid Interface (ALI) to start …

Transgenic Plant Cells For The Cost-Effective Production Of Pharmaceutical Proteins, Maria Gambaro

Create@State

Plant-based systems are becoming an important method for producing pharmaceutical proteins because they can be more cost-effective, and safer compared to traditional production methods which commonly use mammalian cells. This project aims to develop a transgenic plant cell system that can produce a pharmaceutical protein using molecular cloning techniques. A transgenic plant cell has the DNA of another plant integrated into its genome, altering its gene expression to produce different proteins. To begin, a plasmid carrying the gene of interest and the DNA components needed for expression will be designed. The plasmid will then be used to introduce the gene …

Maintaining And Axenizing Live Cyanobacterial Cultures For Bacterial Genome Sequencing, Yufei Wang, Louisa Acquah

SACAD: Scholarly Activities

Harmful cyanobacterial blooms are an

increasing concern in western Kansas, yet the

bloom-forming species in this region remain

poorly characterized. In this study, we

established and maintained axenic

cyanobacterial cultures to support future

genomic and ecological investigations. By

ensuring low contamination levels and stable

growth conditions, this work provides a

foundation for downstream analyses of bloom-

forming cyanobacteria. It contributes to a better

understanding of freshwater ecosystem health

in western Kansas.

Identification Of Covalent Catechin Adducts Of Enoyl-Acp Reductase (Fabi) From E. Coli Using Mass Spectrometry, Francisco G. Atwi, P. M. Joyner, Rustin Ghidari

Seaver College Research And Scholarly Achievement Symposium

Enoyl-ACP reductase (FabI), an enzyme which is inhibited by catechin, is essential for lipid biosynthesis in bacteria (E. coli). Another FabI inhibitor, triclosan, has strong antibacterial effects,1 but overuse can be detrimental to the environment. Flavonoids, a class of dietary compounds, are known to have potent inhibitory effects on FabI and other kinases.2,3,4 Adducts form as a result of the biochemical reaction between flavonoids and cysteine, a modification which can be verified by m/z shifts on the mass spectra.5 Samples of E. coli protein with overexpressed FabI are utilized: the wild type with ordinary primary structure, and mutant type lacking …

Structural Transformation Of A Hydrogel-Forming Cell Division Protein Zapb Of Multidrug Resistant Klebsiella Pneumoniae With Small Molecules, Ayesha Khan, M. Iqbal Choudhary, Sumaira Javaid, Humaira Zafar, Innokentiy Maslennikov, Atia-Tul Wahab

Pharmacy Faculty Articles and Research

Septal ring assembly protein ZapB (EMR18431.1) is involved in Z-ring formation, and nucleoid segregation during the bacterial cell division . It promotes cell division in the initial stages of the cell cycle through direct interaction with FtsZ, thus stimulating Z-ring assembly. The ZapB inhibition can make bacterial cell susceptible to primary antibiotics, and therefore considered as an important approach for adjuvent therapy against MDR bacterial infections. Hence in the current study, ZapB protein of multidrug resistant Klebsiella pneumoniae was cloned, and expressed in E. coli system. To understand its role, and to assess the mechanism of ZapB activation, the characteristic …

Survivin And Caspases Coordinate Proteolytic Cleavage Of The Saga Chromatin Modifying Complex, Elinor Harrison, Alejandro Damian, Cj Talton

Medical Student Research Symposium

Title: Survivin and Caspases Coordinate Proteolytic Cleavage of the SAGA Chromatin Modifying Complex

Elinor Harrison¹, Alejandro Damian¹, CJ Talton¹, Jelly H Soffers¹, Abudu I Bello¹, Kara M Costanzo¹, Joe Bean¹, Ryan D Mohan¹

¹Wayne State University School of Medicine

Background: The Spt Ada Gcn5 Acetyltransferase (SAGA) chromatin modifying complex is a critical regulator of gene expression. Mutation or stoichiometric imbalance of SAGA subunits leads to a spectrum of diseases in model organisms and in humans, including neurodegeneration. SAGA contributes to gene activation through coordinated …