Life Sciences Commons^™

Modeling Nonsegmented Negative-Strand Rna Virus (Nnsv) Transcription With Ejective Polymerase Collisions And Biased Diffusion, Felipe-Andres Piedra

Research Symposium

Background: The textbook model of NNSV transcription predicts a gene expression gradient. However, multiple studies show non-gradient gene expression patterns or data inconsistent with a simple gradient. Regarding the latter, several studies show a dramatic decrease in gene expression over the last two genes of the respiratory syncytial virus (RSV) genome (a highly studied NNSV). The textbook model cannot explain these phenomena.

Methods: Computational models of RSV and vesicular stomatitis virus (VSV – another highly studied NNSV) transcription were written in the Python programming language using the Scientific Python Development Environment. The model code is freely available on GitHub: …

Analysis Of Ssa4 Reporter Expression By Q-Pcr, Susveen Sharanshi, Rebecca Adams

Belmont University Research Symposium (BURS)

The synthesis of genome-encoded proteins via mRNA translation is integral to cell survival. In eukaryotes, such as S. cerevisiae, the mRNA that is produced in the nucleus must be exported to the cytoplasm for translation to occur, and this process is highly regulated. Specifically, the export of mRNA occurs via travel through nuclear pore complexes (NPCs), which are selective doorways embedded in the nuclear envelope. During cellular stress, such as heat shock, the cell needs to regulate gene expression to permit survival, and mRNA export is one step at which this occurs. At these high temperatures, a cell’s proteins …

Crowd Control: Regulating The Spatial Organization Of Biopolymers And Gene Expression By Macromolecular Crowding, Gaurav Chauhan

Doctoral Dissertations

The intracellular environment is crowded with macromolecules that can occupy a significant fraction of the cellular volume. This can give rise to attractive depletion interactions that impact the conformations and interactions of biopolymers, as well as their interactions with confining surfaces. We used computer simulations to study the effects of crowding on biologically-inspired models of polymers. We showed that crowding can lead to attractive interactions between two flexible ring polymers, and we further characterized the adsorption of both flexible and semiflexible polymers onto confining surfaces. These results indicate that crowding-induced depletion interactions could play a role in the spatial organization …

Physiological And Biochemical Thermal Stress Conditions Of The Ribbed Mussel, Geukensia Demissa, From Exposed And Less Exposed Areas In The Intertidal Salt Marsh On Tybee Island, Georgia., Jody E. Erber

Honors College Theses

Geukensia demissa, the ribbed mussel, is a keystone species of Georgia’s coastline that is at risk of experiencing detrimental thermal stress due to climate change. G. demissa interacts positively with a species of salt marsh cordgrass, Spartina alterniflora. Mussels form aggregates beneath salt marsh cordgrass stems where they are shaded and less exposed to sun rays. However, some mussels end up in areas which lack cordgrass and are directly exposed to sun rays. Body temperatures of mussels from exposed areas were found to be higher than mussels from less exposed areas. Thermal stress levels of mussels can be …

Improved Radiation Expression Profiling In Blood By Sequential Application Of Sensitive And Specific Gene Signatures, Eliseos J. Mucaki, Ben C. Shirley, Peter K. Rogan

Biochemistry Publications

Purpose. Combinations of expressed genes can discriminate radiation-exposed from normal control blood samples by machine learning based signatures (with 8 to 20% misclassification rates). These signatures can quantify therapeutically-relevant as well as accidental radiation exposures. The prodromal symptoms of Acute Radiation Syndrome (ARS) overlap those present in Influenza and Dengue Fever infections. Surprisingly, these human radiation signatures misclassified gene expression profiles of virally infected samples as false positive exposures. The present study investigates these and other confounders, and then mitigates their impact on signature accuracy.

Methods. This study investigated recall by previous and novel radiation signatures independently derived …

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Doctoral Dissertations

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …

The Analysis Of Folate-Dependent Transcription Factor Zinc Finger Protein 410, Feifan Xu

Senior Honors Theses

A previous study that introduced dietary folate to mice in the form of folic acid to determine if gene activity would be altered based on this biological molecule demonstrated that mice without folic acid had cognition deficits, and this phenomenon was correlated with altered gene expression in their brains. The included bioinformatic analysis revealed two main transcription factors that bind to proteins in the nucleus, and one is known as the Zinc Finger Protein 410 (Zfp410). Due to the lack of literature explaining the function of this transcription factor, this project is intended to analyze Zfp410 in detail from scratch. …

Identification Of Ires Activity In Cellular Mrnas And Viral Rna Using A Circular Rna Construct, Priyanka Sehta

Legacy Theses & Dissertations (2009 - 2024)

Translation initiation is a critical step in the process of protein synthesis. The canonical way of translation initiation involves ribosomes being recruited to the 7-methyl guanosine cap present at the 5’end of the untranslated region (5’ UTR) of the RNAs. However, viral RNAs and some cellular mRNAs lack this 5’ cap structure and thus deploy an alternate non-canonical translation initiation mechanism. In non-canonical translation initiation, ribosome recruitment is facilitated by the RNA secondary structures called Internal Ribosome Entry Site (IRES) present most often in the 5’ UTR. To measure IRES-mediated translation, the dual luciferase assay has been the gold standard. …

Functional And Physiological Role Of Extra-Hypothalamic Corticotropin Releasing Hormone Neurons In The Nucleus Of The Hippocampal Commissure In Regulation Of Stress Response, Hakeem Kadhim

Graduate Theses and Dissertations

Corticotropin releasing hormone (CRH) neurons located within the paraventricular nucleus (PVN) are known to be involved in regulation of stress responses. Recently, CRH neurons were identified above the PVN within the nucleus of the hippocampal commissure (NHpC) that located in the septum. We hypothesized that CRH neurons in the NHpC play a critical role in the stress response due to their rapid activation and could be a part of the traditional hypothalamo-pituitary-adrenal (HPA) axis. The dissertation addresses the role of 1) CRH expressing neurons in the NHpC compared with those within the PVN utilizing two different stressors, food deprivation (FD) …

Changes In Gene Expression Profiles In Müller Glia Following Exposure To An Α7 Nicotinic Acetylcholine Receptor Agonist, Megan L. Stanchfield

Masters Theses

Previous studies from this lab have determined that dedifferentiation of Müller glia (MG) occurs after application of an α7 nicotinic acetylcholine receptor agonist, PNU-282987 (PNU), to retinal pigment epithelial (RPE) cells in adult rodents. This study was designed to explore the role of the HB-EGF/Ascl1/Lin28a signaling pathway in MG dedifferentiation to retinal progenitor cells. RNAseq was performed on MG following contact with RPE-J cells treated with PNU-282987. Up- or down-regulated genes were compared with published literature of MG dedifferentiation that occurs in lower vertebrate regeneration or with transcript profiles during early mammalian development. Between 8-12 hours, up-regulation was observed in …

Investigating The Toxicology Of Intramuscular Injected Cnt-Ab In Mice Followed By Microwave Hyperthermia., Conner Clark

Honors College Theses

The advent of carbon nanotubes (CNTs) has led to a wide range of research in various fields including cancer therapy for targeting specific localized and site-specific treatment. Carbon nanotubes bound to tumor specific antibodies (Ab) offers specific treatment for cancer cells without affecting surrounding tissue. This treatment makes use of infrared absorptive properties of nanotubes to incinerate both the nanotube and its associated tumor in vivo. We seek to affirm the initial results of CNT in cancer therapy by investigating the toxicological effect in mice injected with CNT-Ab followed by microwave hypothermia. After 1-week post-injection, mice were sacrificed followed …

The Guardian Of The Genome : Regulation Of The Enhancer Networks Governing The P53-Mediated Stress Response, Allison Catizone

Legacy Theses & Dissertations (2009 - 2024)

After fertilization in vertebrates, cells work to build organs, tissues and begin to rapidly differentiate and proliferate. This process is the orchestration of finely tuned signals and perfectly timed gene expression patterns. The first step in gene expression, transcription, is governed by proteins known as transcription factors (TF). TFs are responsible for binding to DNA, altering chromatin structure, and driving activation of other genes based on the organism’s needs. Once the process of development is complete, organisms shift their resources to maintaining homeostasis. Humans regularly encounter outside stressors such as UV radiation, pollution, allergens, and drugs. Cells also accumulate mutations …

Multigene Signatures Of Responses To Chemotherapy Derived By Biochemically-Inspired Machine Learning., Peter K. Rogan

Biochemistry Publications

Pharmacogenomic responses to chemotherapy drugs can be modeled by supervised machine learning of expression and copy number of relevant gene combinations. Such biochemical evidence can form the basis of derived gene signatures using cell line data, which can subsequently be examined in patients that have been treated with the same drugs. These gene signatures typically contain elements of multiple biochemical pathways which together comprise multiple origins of drug resistance or sensitivity. The signatures can capture variation in these responses to the same drug among different patients.

Characterization Of Early Biofilm Formation And Physiology In Neisseria Gonorrhoeae, Kelly Eckenrode

Dissertations, Theses, and Capstone Projects

Many bacteria rely on the dynamics of their extracellular appendages to perform important tasks, like motility and biofilm formation. Interestingly, these dynamics have been linked to physiological responses in some pathogenic bacteria; therefore, it is important to understand more about the role of physical forces in bacteria. I used the causative agent of the human disease gonorrhea, Neisseria gonorrhoeae, as a model system to study the role of physical force on early biofilm formation. The advantage of this system is that cell-cell interactions are controlled by extracellular filaments called type IV pili (tfp). Tfp is composed of monomers that give …

Advances In Gene Ontology Utilization Improve Statistical Power Of Annotation Enrichment, Eugene Waverly Hinderer Iii, Robert M. Flight, Rashmi Dubey, James N. Macleod, Hunter N. B. Moseley

Maxwell H. Gluck Equine Research Center Faculty Publications

Gene-annotation enrichment is a common method for utilizing ontology-based annotations in gene and gene-product centric knowledgebases. Effective utilization of these annotations requires inferring semantic linkages by tracing paths through edges in the ontological graph, referred to as relations. However, some relations are semantically problematic with respect to scope, necessitating their omission or modification lest erroneous term mappings occur. To address these issues, we created the Gene Ontology Categorization Suite, or GOcats—a novel tool that organizes the Gene Ontology into subgraphs representing user-defined concepts, while ensuring that all appropriate relations are congruent with respect to scoping semantics. Here, we demonstrate the …

Decrypting Female Attractivity In Garter Snakes, Holly Rucker

Senior Honors Projects, 2010-2019

Pheromones are utilized by many species as sexual signals driving mate choice, and pheromone production in vertebrates hinges on sex hormone action. Female red-sided garter snakes (Thamnophis sirtalis parietalis) produce a skin-based sex pheromone used by males for mate detection and selection. Estradiol is necessary for pheromone production, yet the specific mechanisms within the skin are unknown. Central to this is the metabolism of testosterone to estradiol via the enzyme aromatase. It is hypothesized that female garter snakes synthesize estradiol locally in the skin and maintain pheromone production via tissue-specific regulation of aromatase. Further, I hypothesize that female …

Transcriptional Regulation Factors Of The Human Mitochondrial Aspartate/Glutamate Carrier Gene, Isoform 2 (Slc25a13): Usf1 As Basal Factor And Foxa2 As Activator In Liver Cells, Paolo Convertini, Simona Todisco, Francesco De Santis, Ilaria Pappalardo, Dominga Iacobazzi, Maria Antonietta Castiglione Morelli, Yvonne N. Fondufe-Mittendorf, Giuseppe Martelli, Ferdinando Palmieri, Vittoria Infantino

Molecular and Cellular Biochemistry Faculty Publications

Mitochondrial carriers catalyse the translocation of numerous metabolites across the inner mitochondrial membrane, playing a key role in different cell functions. For this reason, mitochondrial carrier gene expression needs tight regulation. The human SLC25A13 gene, encoding for the mitochondrial aspartate/glutamate carrier isoform 2 (AGC2), catalyses the electrogenic exchange of aspartate for glutamate plus a proton, thus taking part in many metabolic processes including the malate-aspartate shuttle. By the luciferase (LUC) activity of promoter deletion constructs we identified the putative promoter region, comprising the proximal promoter (−442 bp/−19 bp), as well as an enhancer region (−968 bp/−768 bp). Furthermore, with different …

Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy

Legacy Theses & Dissertations (2009 - 2024)

DksA is a bacterial gene regulator that functions synergistically with the stress alarmone ppGpp to mediate the stringent response. DksA also functions independently of ppGpp to regulate transcription of a number of genes. DksA function is dependent on its binding affinity to RNA polymerase and requires specific interactions between RNAP and catalytic amino acids located on the coiled coil tip, D74 and A76. While much of the previous work on DksA has focused on understanding the mechanisms of action and the numerous gene targets for transcriptional regulation, little is known about the mechanisms by which DksA expression and function may …

Transcriptional Regulation Of Dksa In E. Coli, Daniel Thomas Woods

Legacy Theses & Dissertations (2009 - 2024)

DksA is a global transcription factor that binds RNAP directly to regulate the expression of many genes and operons, including ribosomal RNA, in a ppGpp-dependent or ppGpp–independent manner. It is also involved in facilitating the process of DNA replication by removing stalled transcription elongation complexes that could block the progress of the replication fork. In addition, DksA is important for colonization, establishment of biofilms, and pathogenesis. In order to sustain these various functions, an adequate level of cellular DksA is required. This work tested the hypothesis that the E. coli dksA is substantially regulated at the level of transcription. Using …

Endotoxin Increases Oxidative Stress And Oxygen Tension While Reducing Milk Protein Gene Expression In The Mammary Gland, Alexander Jonathan Spitzer

Graduate College Dissertations and Theses

Mastitis, the inflammation of the mammary gland by bacterial infection, is one of the costliest diseases to the dairy industry primarily due to a loss in milk production. The aim of this study was to investigate the mechanisms underlying reduced milk production during mastitis. We hypothesized that bacterial endotoxin induces cell apoptosis, oxidative stress and increases hypoxia while inhibiting milk gene expression in the mammary gland. To test this hypothesis, mice were bred to pregnancy, and 3 days post-partum the left and right sides of the 4th pair of mammary glands were alternately injected with either the endotoxin liposaccharide (LPS, …

Biology Of Exosomes And Their Microrna Cargos In Human And Bovine Milk, Amy Lynn Leiferman

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Exosomes are small, cargo-containing vesicles secreted by cells to facilitate intercellular communication. Of exosome cargos, microRNAs are especially interesting because of their involvement in gene regulation. Recently, our lab has shown that exosomes and their microRNA cargo are absorbed through the diet and elicit effects exogenously. Human and animal milk contain exosomes, which may have implications in infant and adult nutrition. There is evidence that bovine milk exosomes enhance growth of murine C2C12 myotube cell cultures, but whether this translates to muscle in vivo is unknown. The USDA National Nutrient Database for Standard Reference is lacking up-to-date information about human …

Gesture: An Online Hand-Drawing Tool For Gene Expression Pattern Search, Chunyan Wang, Yiqing Xu, Xuelin Wang, Li Zhang, Suyun Wei, Qiaolin Ye, Youxiang Zhu, Hengfu Yin, Manoj Nainwal, Luis Tanon-Reyes, Feng Cheng, Tongming Yin, Ning Ye

Molecular Biosciences Faculty Publications

Gene expression profiling data provide useful information for the investigation of biological function and process. However, identifying a specific expression pattern from extensive time series gene expression data is not an easy task. Clustering, a popular method, is often used to classify similar expression genes, however, genes with a ‘desirable’ or ‘user-defined’ pattern cannot be efficiently detected by clustering methods. To address these limitations, we developed an online tool called GEsture. Users can draw, or graph a curve using a mouse instead of inputting abstract parameters of clustering methods. GEsture explores genes showing similar, opposite and time-delay expression patterns with …

Investigation Of Bradyzoite Differentiation Initiation In Toxoplasma Gondii, Harim I. Won, Paul H. Davis Ph.D.

Theses/Capstones/Creative Projects

Like other eukaryotic organisms, Toxoplasma gondii promoters feature both constitutive and life-stage regulated cis-elements. Using a transcriptomic microarray approach, a cluster of transcripts upregulated early during bradyzoite differentiation was identified. Computational analysis of the promoter regions of these “up-early” transcripts identified a shared upstream consensus motif, a putative transcription factor binding site. Using a dual luciferase assay adapted for recombinational cloning and reporter gene quantification by qPCR, we demonstrate developmental stage-specific expression of the luciferase reporter gene inserted downstream of the transcription factor binding site. The shared consensus motif was found to be an autonomous cis-element by conversion …

Cancerdiscover: An Integrative Pipeline For Cancer Biomarker And Cancer Class Prediction From High-Throughput Sequencing Data, Akram Mohammed, Greyson Biegert, Jiri Adamec, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Accurate identification of cancer biomarkers and classification of cancer type and subtype from High Throughput Sequencing (HTS) data is a challenging problem because it requires manual processing of raw HTS data from various sequencing platforms, quality control, and normalization, which are both tedious and timeconsuming. Machine learning techniques for cancer class prediction and biomarker discovery can hasten cancer detection and significantly improve prognosis. To date, great research efforts have been taken for cancer biomarker identification and cancer class prediction. However, currently available tools and pipelines lack flexibility in data preprocessing, running multiple feature selection methods and learning algorithms, therefore, developing …

Circular Rna : A Review Of History, Diseases, And Diagnostic Potential, Daniel Conley

Legacy Theses & Dissertations (2009 - 2024)

Abstract

Determining The Role Of Epigenetic Factors In Antifungal Drug Resistance, Abigail R. Gress, Scott D. Briggs, Nina Serratore

The Summer Undergraduate Research Fellowship (SURF) Symposium

Epigenetic factors are proteins that regulate gene expression by altering transcriptional machinery access to nucleosomes, DNA wrapped around histone proteins. Two classes of epigenetic factors are ATP-dependent chromatin remodelers and histone modifiers such as histone methyltransferases (HMTs), proteins that add methyl groups to histone tails. This study focuses on AIF4 (Antifungal-Induced Factor 4), a possible HMT induced upon neutral lipid depletion that we hypothesize is regulating antifungal drug resistance genes. Overexpression of AIF4 results in hypersensitivity to antifungal drugs. Studying epigenetic factors in the yeast Saccharomyces cerevisiae, including AIF4, can lead to better understanding of cell adaptation to their environments …

Microarray Analysis Of Aging-Associated Immune System Alterations In The Rostral Ventrolateral Medulla Of F344 Rats, Sivasai Balivada, Chanran K. Ganta, Yongqing Zhang, Hitesh N. Pawar, Richard J. Ortiz, Kevin G. Becker, Arshad M. Khan, Michael J. Kenney

Arshad M. Khan, Ph.D.

A Comparison Of Nucleosome Organization In Drosophila Cell Lines, Rebecca L. Martin, John Maiorano, Greg J. Beitel, John F. Marko, Graham Mcvicker, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Changes in the distribution of nucleosomes along the genome influence chromatin structure and impact gene expression by modulating the accessibility of DNA to transcriptional machinery. However, the role of genome-wide nucleosome positioning in gene expression and in maintaining differentiated cell states remains poorly understood. Drosophila melanogastercell lines represent distinct tissue types and exhibit cell-type specific gene expression profiles. They thus could provide a useful tool for investigating cell-type specific nucleosome organization of an organism’s genome. To evaluate this possibility, we compared genome-wide nucleosome positioning and occupancy in five different Drosophila tissue-specific cell lines, and in reconstituted chromatin, and then …

Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May

Electronic Theses and Dissertations

In this study, we compared the osmotic stress response of larval and juvenile blue mussels (Mytilus edulis) at the transcriptomic, metabolomic, and whole organism levels. Blue mussels inhabit coastal areas, where they face climate-induced reductions in nearshore salinity. Despite their ecological and economic importance, scientists do not fully understand the underlying transcriptomic and cellular mechanisms of the osmotic stress response in blue mussels or how the ability to respond to stress changes throughout development. Blue mussels spend the first weeks of life developing through several larval stages in the plankton. These early life history stages are more vulnerable …

Elucidating The Interplay Between Sodium Selenite On The Tick Amblyomma Maculatum Selenoprotein Gene Expression, Afnan M. Beauti

Honors Theses

Selenium (Se) is an element recognized as an essential micronutrient in eukaryote organisms. Selenoproteins contain selenium as selenocysteine, the 21st amino acid. Selenium plays a role in cell growth and functioning. At low concentrations, it can induce growth and at high concentrations, it can cause a cell to stop growing and potentially have toxic effects on the cell and organism. When selenium levels are high, oxidative stress results by the production of reactive oxidative species. Selenoproteins, however, can aid the antioxidant response in the cell. Ticks are arthropods of interest, as they are one of few that contain many selenogenes, …