Cell Biology Commons^™

Architects Of Mrna Fate: Molecular And Cellular Control Of P-Body Organization In The Drosophilia Melanogaster Female Germline, Samantha Milano

Dissertations, Theses, and Capstone Projects

Processing bodies (P-bodies) are cytoplasmic ribonucleoprotein condensates that regulate mRNA storage, translational repression, and decay. While the biochemical principles governing condensate assembly have been extensively studied in vitro, how P-body organization is established and dynamically regulated in vivo to control specific mRNA populations remains poorly understood. This dissertation investigated the molecular and cellular mechanisms that govern P-body architecture and function in the Drosophila melanogaster female germline. First, I identified the conserved LSm protein Trailer Hitch (Tral) as a central organizer of P-body architecture. Using quantitative confocal and super-resolution microscopy combined with chemical perturbations, I showed that Tral coordinates the …

Effect Of Partial Ablation Of Skeletal Dynamin Related Protein 1 On Mitochondrial Health, Inflammation, And Fibrosis In A Mouse Model Of Duchenne Muscular Dystrophy, Tessa L. Duzz

Graduate Masters Theses

Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disorder characterized by muscle weakness, degeneration, fibrosis, and impaired muscle regeneration. Mitochondrial dysfunction is an early pathological feature of DMD and has been linked to excessive mitochondrial fission. Dynamin-related protein 1 (Drp1) is a central regulator of mitochondrial fission, a key process in regulating mitochondrial quality and function. Inhibition of Drp1-mediated mitochondrial fission has shown promise as a potential therapeutic target for alleviating pathology and dysfunction in dystrophic muscle. The objective of this study was to determine whether partial skeletal muscle-specific ablation of Drp1 could improve muscle pathology and mitochondrial health in …

The Role Of Seed Mix Characteristics And Soil Amendments During Post-Agricultural Prairie Restoration, Valerie N. Thurston, Michaela J. Woods, Madelaine Gregory, Mary C. Lloyd, Ryan W. Mcewan

Biology Faculty Publications

Introduction: Prairie restoration on degraded lands may be influenced by seed mix characteristics, including species richness and legume establishment. Soil amendments may facilitate restoration; however, the practical usefulness of techniques such as applications of whole soil and leaf mulch remains relatively unclear.

Objectives: We assessed whether increasing species richness and legume content in seed mixes enhances prairie restoration success and examined how soil amendments interact with seed mix composition to influence cover, species richness, diversity, and legume establishment.

Methods: We conducted a field experiment on a 12-ha post-agricultural site in Ohio, U.S.A. Twenty 50 × 50 m plots received one …

Homocysteine Thiolactone From Translation Proofreading Is An Endogenous Ligand For Cell-Cell Signaling By The Receptor Sdia, Lorenzo Eugenio Leiva, Roberto A. Zúñiga, Gregory J. Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Several widespread mechanisms enable cellular communication and coordinate the behavior of bacterial populations. The modules responsible for cellular communication are often found in matching pairs: an enzyme that synthesizes a signal molecule and a specific receptor that decodes it. A notable exception is Escherichia coli SdiA, a homolog of known N-acyl-homoserine lactone (AHL) receptors, for which no corresponding AHL synthase exists. SdiA is an orphan receptor that enables cross-talk by sensing AHLs from other bacterial species. In this work, we investigated whether homocysteine thiolactone (HTL), an AHL-like molecule arising from a proofreading reaction of methionyl tRNA synthetase (MetRS) to correct …

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 …

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 …

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 …

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 …

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 …

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. …

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 …

Analysis Of Mitochondrial Dna Haplotype Groups For South Texas Canids, Canis Rufus, After Past Hybridization Events, Isabella Lopez

Presentations - 2026

mtDNA: mitochondrial DNA; passed from maternal parent to offspring (Haplotype)

Haplotype:  a group of genes or genetic markers inherited together from a single parent (Haplotype)

Mitochondrial DNA haplotypes specific sequences of mtDNA that is passed exclusively from maternal parent to offspring (Giles et al. 1980)

Pro's:

It is passed unchanged from mother to offspring, meaning it is fairly stable (Giles et al. 1980)

Each cell has multiple mitochondria vs one nucleus , which means mtDNA it is more likely to be recoverable from degraded samples like scat (Templeton et al. 2013)

Untangling G-Quadruplexes In Dna: The Effects Of Nucleotide Excision Repair, Jaidelin Alvardo, Abiageal Riley, Erick Morales Orrante, Raynne Malik

Posters - 2026

Nucleotide Excision Repair (NER) remo ves bulky DNA lesions that are attributed to UV irradiation, environmental mutagens, and chemo-therapeutic agents (Schärer, CSH Perspectives Biology, 2013). G4- quadruplexes are formed by four guanines hydrogen bonded together to form a planar ring, and stacking of the hydrophobic G quartets stabilizes the quadruplex structure Capra et al.,PLoS Computational Biology, 2010). A surplus of this structure is linked to genomic Instability and cancer development.

Prior studies indicate that because NER eliminates large lesions of DNA, there may be a link to the removal of G4-quadruplexes through Nucleotide Excision Repair (De Magis et al, Nature,2020). …

Exploring Base Excision Repair Using Gene Knockout, Gregory Guantos, Cailyn Brock, Kamily Visser, Dylan Vargas

Posters - 2026

•             Base Excision Repair (BER) fixes damaged 3DNA bases throughout the cell cycle by removing damaged bases and replacing either one nucleotide in short-patch BER or a short stretch of nucleotides in long-patch BER. (Hindi, 2021, Cellular and Molecular Life Sciences:CMLS)

•             4G-quadruplexes (G4s) are 4 stranded secondary DNA structures formed in guanine rich areas of DNA and RNA. (Rhodes, 2015, Nucleic Acids Research)

The URA3 plasmid was used as a PCR template to make a gene deletion construct, then yeast were transformed so APN1 was replaced by URA3. 2APN1 encodes a major DNA repair enzyme in yeast, and strains …

Nucleotide Excision Repair In Yeast, Kinleigh Mines, Larry Ramirez, Jacob Rodriguez, Delynda Gonzalez

Posters - 2026

DNA damage occurs constantly in cells due to environmental factors and normal cellular processes, making DNA repair pathways essential for maintaining genomic stability (Hindi et al., 2021). One major repair mechanism is Nucleotide Excision Repair (NER), which is responsible for recognizing and removing bulky DNA lesions that distort the double helix structure (Scharer, 2013). In Saccharomyces cerevisiae (yeast), the RAD14 gene plays a critical role in this pathway by helping identify and initiate repair of damaged DNA (Scharer, 2013). Another source of instability comes from the formation of G-quadruplex (G4) structures, which are secondary DNA configurations that can interfere with …

Characterization And Advancement Of Molluscan Venom Gland Cell Model Systems, James V. Parziale

Dissertations, Theses, and Capstone Projects

Venomous mollusks, including cone snails and coleoid cephalopods, produce rich repertoires of bioactive peptides with profound effects on cellular physiology, yet there are few tractable experimental systems that exist to study their development, maintenance, and venom secretion. Although therapeutics such as the cone snail peptide Ziconotide demonstrate the biomedical potential of molluscan venoms, progress in understanding how venom glands form, function, and evolve has been hindered by the lack of reliable husbandry and the complete absence of in vitro cell models. Modern comparative genomics has revealed widespread convergent evolution across venomous lineages, but molluscan datasets remain underrepresented, limiting insights into …

Reverse Micelles Produce Hydroxyapatite Nanoparticles As More Efficient Gene Delivery Carriers Than Regular Micelles, Vuk Uskoković

Administration and Staff Articles and Research

Hydroxyapatite (HAp) is an effective inorganic gene delivery carrier due to its ability to transport genetic cargo across cell membranes, protect it from proteolysis, and enable escape from late endosomes via pH-controlled dissolution. However, its transfection efficiency remains lower than that of viral agents, prompting studies of hybrids with cationic molecules or phases to enhance the gene delivery performance. This study reports on the synthesis of HAp in regular and reverse micellar regions of a ternary microemulsion system composed of cetyltrimethylammonium bromide (CTAB), 1-hexanol and water. Spectroscopic characterization revealed that CTAB headgroups adopted more ordered supramolecular conformations in reverse micelles …

Generating A Gfp Reporter Via Crispr To Visualize Ssa4 Export, Aara Khairollahi, Rebecca Adams

SPARK Symposium Presentations

In eukaryotic cells, the transport of mRNA from the nucleus to the cytoplasm is a very regulated process controlled by nuclear pore complexes (NPCs). During stress conditions, such as heat shock, most mRNA export is inhibited in Saccharomyces cerevisiae, yet the transcript for SSA4, a gene responsible for refolding denatured essential proteins, is exported. The mechanism behind this selective export remains unknown. To investigate this, we used CRISPR-Cas9 to generate a reporter strain in which the SSA4 open reading frame was replaced or inserted with green fluorescent protein (GFP). This reporter is designed to produce GFP only under conditions that …

A Framework For Characterizing The Peripheral Immune Isonome Using Long-Read Single-Cell Rna Sequencing And Its Relevance To Neurological Disease, Patricia Hayes Doyle

Theses and Dissertations--Neuroscience

Long-read single-cell RNA sequencing provides an opportunity to understand human health and disease at isoform resolution, revealing cellular diversity and disease mechanisms difficult to resolve with bulk or short-read methodologies.

Using a modified PIPseq workflow and computational pipeline adapted for Oxford Nanopore (ONT) sequencing, we profiled isoform usage across immune cells, integrating marker expression and isoform discovery, generating the largest long-read single-cell dataset of human immune cells from a single individual to date. We identified non-canonical protein-coding variants of GZMB and CD3G enriched in unexpected cell types. We also discovered novel transcripts from CMC1 and LYAR with cell-type-specific signatures that …

Perfluorooctane Sulfonate (Pfos)-Induced Disruption Of Mitochondrial Activity And Cell Adhesion In Liver Cells, Phuong Dam Nam Tran

Graduate Theses/Dissertations

Perfluorooctane sulfonate (PFOS) is a persistent environmental pollutant associated with potential hepatoxic effects and other health risks. Despite its widespread distribution, the mechanisms underlying its toxicities remain to be fully understood. To investigate PFOS toxicology, my study utilized HepG2 and THLE-2 human hepatic cell models to replicate conditions reflecting PFOS accumulation in the liver. Cell viability, cell stress, and cell death assays were conducted to assess the toxicological influence of the chemical on both cell lines. Total RNA extraction was performed, followed by cDNA sequencing, and RT-qPCR. The XTT viability assay revealed a dose-dependent decrease in number of viable cells …

Determining Genes Involved In Recovery From Chemotherapy In 4t1, Emt6, And Eo771 Breast Cancer Cells, Akash Jagdeesh, Joseph Landry Ph.D.

Undergraduate Research Posters

Breast cancer is one of the most common types of cancer, and often has poor prognosis. Traditional treatments for breast cancer include chemotherapy, which involves a chemical attack on all growing cells within the body. However, these treatments are not 100% effective, and patients might experience recurrence in their cancer months or years after achieving remission. Cancer cells can evade chemotherapy through five mechanisms: senescence, quiescence, cytoprotective autophagy, and apoptosis/necroptosis suppression. Prior studies have conducted CRISPR screens and experiments involving inhibition of epigenetic regulators, to alter the regulation of genes that can contribute to breast cancer chemotherapy resistance. This study …

Epigenetic Modifications In Dedifferentiated Liver Cells To Restore Lost Liver Function, Shreya Sharma

Masters Theses

The goal of the study is to investigate whether the epigenetic modifications can enhance the restoration of liver gene expression in dedifferentiated hepatoma cells or not. For the study, we used dedifferentiated H11 hepatoma cell lines which overexpress one of a panel of introduced candidate liver-enriched transcription factors H11-HNF1a, H11-CREB3L3, H11-CREG1, H11- HHEX, H11-HNF6, and H11-IGFBP1. The cells were treated with the DNA methyltransferase inhibitor 5-azacytidine and the histone deacetylase inhibitor sodium butyrate, both individually and in combination. Gene expression analysis was determined by RT-qPCR, which revealed that while transcription factor overexpression alone produced limited activation, epigenetic modulation, particularly Histone …

Fluorescent Protein Imaging Approaches Uncover Dynamic Subcellular Distribution Of Core Clock Proteins In Neurospora Crassa, Ziyan Wang

Dartmouth College Ph.D Dissertations

Circadian clocks are endogenous self-sustained timekeeping systems that allow organisms to anticipate and adapt to daily environmental cycles. Found in diverse forms of life, these molecular clocks regulate the expression of ~ 40% of the genome in animals, fungi, and plants. In animals and fungi, circadian oscillators are built on transcription-translation feedback loops (TTFLs), in which positive regulators drive the expression of negative regulators which, once synthesized and imported into the nucleus, inhibit their own activators. This precisely regulated negative feedback incorporates multiple steps of delays that are essential for generating ~24-hour rhythms. Through these mechanisms, circadian clocks temporally coordinate …

Development Of Self-Assembled Polymeric Polyplexes For Microrna Delivery: Toward Treatment Of Alcohol-Associated Liver Disease, Marjina Akter Kalpana

Theses & Dissertations

Self-assembled polymeric polyplexes have the potential to serve as an RNA interference (RNAi) delivery platform for the combined inhibition of CXCR4 and miR-155 in the treatment of alcohol-associated liver disease (AALD). A central challenge in RNA delivery is balancing the extracellular stability of polyplexes, cellular uptake, and intracellular release of RNA cargo. We developed polymeric polyplexes using the CXCR4-antagonist polymer PAMD, designed to target CXCR4 on activated hepatic stellate cells (HSCs) and deliver therapeutic miRNA to activated Kupffer cells (KCs) in fibrotic liver. We improved the polyplexes by cholesterol modification of PAMD and by PEGylation of PAMD-Ch. The cholesterol modification …

The Genetic And Environmental Determinants Of Stress Resilience Across Model Systems, Carson Len Stacy

Graduate Theses and Dissertations

Survival in fluctuating environments demands that organisms effectively anticipate and respond to future challenges. This capacity is shaped by both genetic background and environmental context. In this dissertation, I apply a population aware lens to explore how genetic diversity and environmental conditions intersect to shape stress survival. Integrating functional genomics and transcriptomics in Saccharomyces cerevisiae (brewer’s yeast) and a vertebrate (common canary) system, I dissect gene-by-environment (GE) interactions that underpin resilience. First, I move beyond a single reference genome by using a pan-genomic CRISPR knockout screen to assess osmotic stress survival across diverse S. cerevisiae isolates. This analysis reveals a …

The Chromosome Complement Of Male Chrysoperla Rufilabris (Burmeister, 1839), With Evidence Of Distance Segregation In Meiosis I, Valoria G. Maslin, Allison M. Eisenhauer, Leocadia V. Paliulis

Faculty Journal Articles

Neuropteran insects display a phenomenon called distance segregation during male meiosis I, where the X and Y chromosomes are unconnected from prometaphase I through anaphase I. Here we investigate chromosome number and patterns of chromosome segregation of a previously unstudied Neuropteran: the green lacewing, Chrysoperla rufilabris (Burmeister, 1839). Testes of male C. rufilabris were isolated and prepared following a chromosome squash method. Living meiosis I spermatocytes were also imaged. The data revealed a chromosome number of 2n=12 in males (2n=10+XY) and evidence of distance segregation of X and Y chromosomes in meiosis I spermatocytes.

Retinal Precursor Cell Enriched Multiomic And Pseudo-Time Analysis Of Developing And Reprogrammed Photoreceptors, Brendon M. Patierno

Dissertations, Theses, and Capstone Projects

The vertebrate retina is a complex tissue made up of seven major cell subtypes which during development must differentiate and localize into a highly organized structure. These neuronal cells do not regenerate if damaged or diseased, and the progressive deterioration of cone photoreceptor cells is the leading cause of age related blindness. Currently there are no cures for this disease, but one promising therapeutic avenue is cell transplantation research. If we can further elucidate the gene regulatory networks that define cone cell development, this knowledge could be applied to the generation of healthy cone cells in clinically relevant models.

The …

Bmp Signaling Co-Regulation Of Immune Response And Lipid Metabolism, Katerina K. Yamamoto

Dissertations, Theses, and Capstone Projects

The Bone Morphogenetic Proteins (BMPs) are secreted peptide ligands of the Transforming Growth Factor beta (TGF-β) family, initially identified for their roles in development and differentiation across animal species. They are now increasingly recognized for their roles in physiology and infectious disease. In the nematode Caenorhabditis elegans, the BMP ligand DBL-1 controls fat metabolism and immune response, in addition to its roles in body size regulation and development. DBL-1 regulates classical aspects of innate immunity, including the induction of anti-microbial peptides. We theorized that BMP-dependent regulation of fat metabolism could also promote resilience against microbial pathogens. We found that …

Development Of Emerin Mrna Lipid Nanoparticles To Rescue Myogenic Differentiation., Nicholas Marano, Liza Elif Guner, Rachel S Riley, James M Holaska

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Emery-Dreifuss muscular dystrophy 1 (EDMD1) arises from mutations in EMD. Most EDMD1 patients lack detectable emerin expression. They experience symptoms such as skeletal muscle wasting, joint contractures, and cardiac conduction defects. Currently, physicians rely on treating patient symptoms without addressing the underlying cause-lack of functional emerin protein. Thus, there is a need for therapeutic approaches that restore emerin protein expression to improve patient outcomes. One way would be to deliver emerin mRNA or protein directly to affected tissues to restore tissue homeostasis. Here, we evaluated the utility of lipid nanoparticles (LNPs) to deliver emerin mRNA to diseased cells. LNPs …