Digital Commons Network^™

Characterizing The Dynamic Localization Of Cmi In Early Drosophila Development, Asra Habibullah

Master's Theses

The COMPASS-like family of lysine methyltransferases, MLR/MLX complexes, are epigenetic regulators that are essential for normal development through the methylation of the fourth lysine residue on histone 3 (H3K4), a universal epigenetic mark associated with active transcription. This family of complexes is highly conserved from yeast to mammals and the genes encoding the human MLR complexes have been associated with various developmental diseases and cancers (Dingwall and Fagan, 2019). In D. melanogaster, the enzymatic methyltransferase core of this complex is composed of two proteins: Cara Mitad (Cmi, also known as Lpt) and Trithorax-related (Trr). Although these proteins have been shown …

Targeting The Subacute Progression Of Hippocampal Cellular Senescence Following Repetitive Mild Traumatic Brain Injury, Jacob Edward Exline

Master's Theses

Repetitive mild traumatic brain injury (rmTBI) increases an individual’s risk for developing persistent deficits in recognition memory with symptoms experienced by up to 30% of rmTBI patients. Cellular senescence has been suggested as an underlying mechanism of persistent rmTBI symptoms; however, the subacute progression of cellular senescence following rmTBI has not been evaluated. Furthermore, the use of subacute testosterone administration to treat persistent recognition memory deficits and the cellular and molecular underpinnings has yet to be well characterized. Our lab utilizes a 5-hit closed-head rmTBI rat model to induce deficits in recognition memory and determine the effects of subacute testosterone …

How To Build A Cortex: Coordinated Assembly Of Cortical Septins And Actomyosin In The Leader Bleb, Asia Marie Paguntalan

Master's Theses

In confined spaces, migrating cells can undergo mesenchymal-to-amoeboid transitions by altering their cortical dynamics and adhesion with the environment. Septins frequently associate with cortical actin and non-muscle myosin (NMII), but the functional nature of these interactions remains unclear. Upon non-adhesive confinement and NMII enrichment, fibroblasts can switch to a fast, leader bleb-based mode of motility, characterized by the absence of adhesions and stress fibers and formation of a single, elongated leader bleb. During this transition, cortical actin remodeling and polarized NMII contractility drive leader bleb stabilization by generating long-range cortical flows, in coordination with changes in septin localization and assembly …

Incorporating Sex Chromosomes In Transcriptome Prediction Models And Improving Cross-Population Prediction Performance, Daniel S. Araujo

Master's Theses

Transcriptome prediction models built with data from European-descent individuals are less accurate when applied to different populations because of differences in linkage disequilibrium patterns and allele frequencies. We hypothesized multivariate adaptive shrinkage may improve cross-population transcriptome prediction, as it leverages effect size estimates across different conditions - in this case, different populations. To test this hypothesis, we made transcriptome prediction models for use in transcriptome-wide association studies (TWAS) using different methods (Elastic Net, Matrix eQTL and Multivariate Adaptive Shrinkage in R (MASHR)) and tested their out-of-sample transcriptome prediction accuracy in population-matched and cross-population scenarios. Additionally, to evaluate model applicability in …

Characterization Of The Full-Length Bag3 Protein And Stress Induced Formation Of Bag3-Z, Ahmed Gamal Abdalla Zied

Master's Theses

Bcl2-associated athanogene-3 (BAG3) is a pro-autophagy co-chaperone that we havepreviously shown localizes to the cardiac sarcomere and is critical for proteostasis and maintenance of normal sarcomeric function. Indeed, BAG3 loss in heart failure (HF) results in accumulation of ubiquitinated sarcomeric proteins, and depressed maximum force generating capacity (Fmax). However, how BAG3 is regulated in the cell is not well understood, with uncertainty about its structure and proteoforms. During our analysis of human heart tissue, BAG3 appears as a “doublet”, with one band at 74 kDa (BAG3-Z) and a second at a higher 85 kDa (BAG3-FL). Previous studies hypothesized the full-length …

A Population Level Examination Of The Incredible Fruit Diversity In Astragalus Lentiginosus, Quinn Thomas

Master's Theses

Astragalus lentiginosus is the most taxomically diverse species in the North American flora with over 40 recognized varieties. The incredible diversity within A. lentiginosus, particularly in respect to its fruit morphology, makes it an exceptional model to study adaptation and evolution. However, it remains unknown whether fruit morphology is an adaptation and, if so, the extent to which selection or neutral evolutionary processes shape the striking diversity in this trait. In order to understand the adaptive significance of fruit morphology we must first understand the genetic structure of A. lentiginosus. Varieties of A. lentiginosus vary considerably in their range size …

Comparison Of Taxonomy Assignment And Strain Detection In Urobiome Communities Using 16s Rrna Sequencing And Shotgun Metagenomic Sequencing, Delaney Sauer

Master's Theses

Advancements in sequencing technologies have enabled scientists to gain insight into the microbes that inhabit the human body, including the urinary tract. Cataloging the bacteria that inhabit the urinary tract has primarily relied on amplification and sequencing of specific variable regions of the 16S rRNA gene enabling genus-level taxonomic identification. Recently, shotgun metagenomic sequencing has been employed such that bacterial taxonomy as well as the functionality that they encode can be inferred. In this study, we compare taxonomies assigned by 16S sequencing and shotgun metagenomic sequencing of the urinary microbiota (urobiome) of females with and without a clinical diagnosis of …

Identification Of New Substrates From Pseudomonas Aeruginosa Exos, Adam V. Thota

Master's Theses

Pseudomonas aeruginosa is a gram-negative environmental bacterium that uses its intrinsic and acquired antibiotic resistance to infect patients with compromised epithelium, such as cystic fibrosis and burn wounds, and corneal keratitis. In order to cause disease, most strains of P. aeruginosa use the type three secretion system (T3SS) to disrupt cellular signaling and integrity. However, P. aeruginosa may also secrete exotoxins after invading host cells, which prolongs host cell death and maintains an intracellular niche. Of the T3 secreted effector toxins, ExoS, specifically the ADP-ribosyltransferase activity of ExoS, was shown to delay the death of invaded corneal cells, but it …

Cataloging And Engineering Temperate Coliphages Of The Human Urinary Microbiome, Elias Crum

Master's Theses

In the US, around 60% of females will be diagnosed with a Urinary Tract Infection (UTI) in their lifetime, and Escherichia coli is the most implicated etiological agent in UTIs. Despite its frequent association with lower urinary tract symptoms, recent studies have found that the urinary microbiome (UMB), the viral, bacterial, and fungal resident members of the urinary tract, of healthy females can also consist of E. coli. While most research has focused on the bacterial constituents of the UMB, bacteriophages, viruses that infect bacteria, are far more abundant. Bacteriophages (phages) of other human microbiomes have been shown to play …

Interplay Between Human Microbiota And Celiac Disease, John James Colgan

Master's Theses

Celiac disease is an autoimmune disorder of the small intestine in which gluten, an energy-storage protein in wheat and other cereals, elicits an immune response leading to villous atrophy. Despite a strong genetic component, the disease arises sporadically over the lifetime leading us to hypothesize the microbiome might be a trigger. Here, we re-examined 16S data from 3 prior studies examining celiac disease and the microbiome with newer computational tools: the dada2 and PICRUSt 2 pipelines. Our results both confirmed findings of previous studies and generated new data regarding the celiac microbiome of India and Mexico. The datasets were also …

Phylogenetic Relationships Among Fishes In The Order Zeiformes Based On Molecular Data From Three Mitochondrial Loci, Lindsay Scarpitta

Master's Theses

The Zeiformes (dories) are mid-water or deep (to 1000 m) marine acanthomorph fishes with a global, circumtropical, and circumtemperate distribution. Some species have a near-worldwide distribution, while others appear to be regional endemics, e.g., near New Zealand. Six families, 16 genera, and 33 species are currently recognized as valid. Relationships among them, however, remain unsettled, especially in light of recent proposals concerning the phylogenetic placement of zeiforms within the Paracanthopterygii rather than allied with beryciforms or percomorphs. The present study uses mtDNA characters to investigate zeiform interrelationships given their revised phylogenetic placement and attendant changes to their close outgroups, carried …

Polyomavirus Jcpyv And Its Role In The Urinary Tract, Rita Lauren Mormando

Master's Theses

Polyomaviruses are the smallest closed-circular supercoiled double-stranded viruses found in the human microbiota. The polyomavirus JC (JCPyV) is most commonly found within the urinary tract, and prior studies estimate that 20-80% of older adults carry JCPyV. In very rare cases, JCPyV leaves the kidneys, causing progressive multifocal leukoencephalopathy. However, the role of JCPyV within the urinary tract remains an open question. In a prior study conducted by our group, the bladder microbiota of females with and without overactive bladder symptoms (OAB) were sequenced. Interestingly, JCPyV was only detected in females with OAB; none of the control (“asymptomatic”) microbiota contained JCPyV. …

Role Of Tetraspanins In Sars-Cov-2 Fusion And Entry, Marcos Saul Santiago Figueroa

Master's Theses

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the pandemic the world has been facing in recent years. Even as new countermeasures are developed, there is still much we don’t know in terms of its entry into host cells. Tetraspanins are transmembrane proteins that are near ubiquitous amongst cell types. They fulfill numerous roles, including that of a viral co-receptor. Here, we considered whether tetraspanins, specifically CD9, CD63, and CD81 influence SARS-CoV-2 fusion and entry. Using ACE2-LgBit and tetraspanin overexpressing EVs and HeLa cells, we find that the presence of excess tetraspanins inhibit fusion and entry. However, we …

Exploring The Role Of Lactobacillus Jensenii And Lactobacillus Mulieris In The Urogenital Tract, Adriana Daniela Ene

Master's Theses

Lactobacillus is a predominant species of the urogenital tract and it has been found in females with and without lower urinary tract symptoms. The Lactobacillus genus is thought to be beneficial to the host due to its capability to produce hydrogen peroxide, secondary metabolites, and lactic acid. L. jensenii is an organism frequently isolated from the urogenital tract. In March 2020, a new sister taxon of L. jensenii was described, L. mulieris. Shortly thereafter we produced a genomic analysis of all publicly available genomes (n = 43) which reclassified some L. jensenii as L. mulieris. This motivated the in-depth study …

The Impacts Of Framework Mutations On Steady-State Kinetics Of An Aldolase Abzyme, Charles Andrew Mettler

Master's Theses

During affinity maturation, antibodies acquire point mutations that lead to enhanced binding strength to a particular ligand while simultaneously becoming more conformationally restricted as they become increasingly complementary to their ligand’s electrostatic geometry. This property has catalytic potential in transition-state (TS) stabilization whereby kinetic barriers (i.e., the energetic gap between the substrate and its TS) are reduced and reaction rates are enhanced. This basic mechanism is thought to underlie the majority of the rate enhancement observed for enzymes. A key integration of antibody binding specificity and strength with enzymatic catalytic strategy is the development of catalytic antibodies (“abzymes”). Abzymes are …

Integrating Current Analyses Of The Breast Cancer Microbiome, Sidra Sohail

Master's Theses

Breast cancer is the leading cause of cancer death for women in the US. Many cancertypes have significant associations with their resident microbial communities - emerging evidence suggests that breast cancers also interact with the local tissue-associated microbiota. Studies have examined the relationship between breast cancer and its microbiome, however, the studies varied in their approaches used to evaluate these relationships. Microbiome research advances rapidly and analysis pipelines and databases are updated frequently. This dynamic environment makes inter-study comparisons and superficial evaluations challenging as no two studies are using the same standards for evaluation. Researchers have observed the microbiota of …

Interrogating Antagonistic Differences Among Pseudomonas Aeruginosa Cdia Alleles, Haotian Yang

Master's Theses

Bacteria are complex social organisms that live within mixed communities where microorganisms compete for limited resources. We studied Contact-Dependent Growth Inhibition (CDI), a particular type of competition mediated by a type 5b, or two-partner, secretion system that is widely spread among Gram-negative bacteria. CdiB and CdiA make up the two-partner secretion system that mediates CDI. CdiB translocates CdiA to the cell surface, and CdiA delivers its C-terminal toxin domain to the target cell. The C-terminal toxin (Tox) domain of CdiA is highly diverse. We studied Tox domains of various Pseudomonas aeruginosa clinical isolates. We found different strains that contain unique …

Three-Dimensional Staging Series Of Anolis Sagrei, Lilian Epperlein

Master's Theses

With the rapid rise of Evo-devo and the concurrent development of new imaging techniques, comparative studies of development have accelerated over the last decade. Squamates, lizards and snakes, lack a traditional experimental model species for developmental investigations, yet are important for understanding fundamental evolutionary questions because of their remarkable diversity. However, several squamate species have growing communities of biologists building new resources for comparative and experimental studies of lizard development. Creation of detailed embryological atlases for these species will help promote their advancement. In the past, scientists have had to rely on destructive methods to take apart biological samples which …

The Role Of Ly49 Receptors In Maintaining Healthy Murine Pregnancy, Michelle Belmont

Master's Theses

Natural Killer (NK) cells are abundant in pregnancy and contribute to the health of the fetus. Uterine NK (uNK) cells provide less cytotoxic function than their conventional NK (cNK) cell counterparts. Various combinations of Killer Immunoglobulin Receptor (KIR)- Human Leukocyte Antigen (HLA) on maternal NK and fetally derived cells, respectively, can have different effects on the health of pregnancy in humans. Murine NK cells contain Ly49 receptors, an equivalent to KIRs. Therefore, Ly49 receptor interactions with fetally-derived MHC-I molecules can be a valuable model for studying the role of NK cells in pregnancy. The process of spiral artery remodeling can …

Phenotypic Analysis Of Murine Gut Associated Lymphocytes, Madison Flood

Master's Theses

γδ T cells are important in the role of immune homeostasis, especially in relation to the gut. It has been shown that there is a higher proportion of γδ T cells in the intestines than in circulation. With this knowledge, our lab focused on understanding the mechanisms of these cells, specifically regarding immune tolerance. In our preliminary research, we identified a subset of γδ T cells that express Foxp3, a transcription factor essential for the functioning of regulatory T cells, in the neonatal (5 day old) intestine. We hypothesized that these Foxp3+ γδ T cells have immunosuppressive functions upon exposure …

Bisacodyl Limits Chikungunya Virus In Vitro And Is Broadly Antiviral, Natalie June Lomascolo

Master's Theses

Identifying novel antivirals requires significant time and resource investment, and the continuous threat of viruses to human health necessitates commitment to antiviral identification and development. Developing antivirals requires years of research and validation, and recent outbreaks have highlighted the need for preparedness in counteracting pandemics. One way to facilitate development is to repurpose molecules already used clinically. By screening such compounds, we can accelerate antiviral development. Here, we screened compounds from the National Institutes of Health’s Developmental Therapeutic Program for activity against chikungunya virus, an alphavirus that is responsible for a significant outbreak in the Americas in 2013. Using this …

Elucidating The Function Of An Evolutionarily Conserved Col2Α1 Isoform During Vertebrate Development, Charles Lantz H. Ingersoll

Master's Theses

ABSTRACT

Formation of skeletal structural elements during vertebrate embryogenesis is largely a

conserved evolutionary process that employs numerous conserved genes and pathways. One

critical gene in this process is the highly conserved vertebrate Type II Collagen alpha 1 (col2α1).

It produces multiple splice isoforms that have different functions and expression patterns during

skeletogenesis. Two of the primary isoforms are of great interest; variant 1, the primary

embryonic isoform, and variant 2, a post embryonic isoform. While the more commonly known

post-embryonic isoform has been well studied over the last 30 years, identification of a unique

role for the evolutionarily conserved …

Development And Characterization Of A Tissue-Specific Reporter Line For Monitoring Circadian Clock Transcriptional Activity, Lilyan Mather

Master's Theses

Daily rhythms in physiology and behavior are produced by a circadian system consisting of a central clock located in the brain and peripheral clocks located in various peripheral tissues. Circadian clocks track time of day through the presence of a molecular clock that functions as a transcriptional-translational feedback loop. In the nucleus, the transcription factors CLOCK (CLK) and CYCLE (CYC) activate transcription of clock genes period (per) and timeless (tim). PER and TIM proteins slowly accumulate in the cytoplasm before entering the nucleus, where they inhibit CLK and CYC, and therefore repress their own transcription. Degradation of nuclear PER and …

Investigating The Role Of Nagc Reveals It To Be A Global Regulator, Natasha Peterson

Master's Theses

Bacterial colonization of host surfaces can result in symbiotic or pathogenic associations.As bacteria becomes more resistant to antibiotics, pathogenic bacterial colonization poses an increasing risk to human health. Symbiotic associations that have beneficial outcomes for both the host and the microbe can serve as models to investigate how bacterial processes affect colonization of host surfaces. The symbiotic relationship between the Gram-negative, bioluminescent bacterium Vibrio fischeri and the Hawaiian bobtail squid is one such model (E. V. Stabb & Visick, 2013). The study of this exclusive relationship has developed in a way where in vitro phenotypes can predict the ability of …

Comparison Of Feeding Functional Morphology Development In North American Esocids, Cheryl Theile

Master's Theses

Esocidae is a family of freshwater fishes within order Esociformes known for its long, cylindrical bodies, duck-bill snouts, and an impressive number of sharp teeth. There are four species, including two subspecies, in North America with areas of overlap of their geographic distribution. These ambush predators change diets from invertebrate prey to vertebrate prey during their first year of life, and the timing of this shift varies between species. In particular, the sister species Esox lucius (Northern Pike) and Esox masquinongy (Muskellunge) overlap in the upper Midwest, but E. masquinongy transitions to a vertebrate diet sooner in its development than …

Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie

Master's Theses

Life-history characteristics (e.g., age and growth) have been used extensively to understand the temporal population dynamics of fish species, but less so within a phylogenetic framework. This study investigates life-history characteristics within the suborder Gadoidei (order: Gadiformes) and to test the extent of phylogenetic signal for those characteristics. To accomplish this, a phylogeny of Gadoidei was first constructed based on both mitochondrial and nuclear genes. Within this phylogenetic framework, life-history traits, including growth rate, age at maturity, and longevity, as well as ecological data, such as water depth and diet type, were mapped to the phylogeny using parsimony analysis to …

Unveiling Bacterial Hitchhikers In The Urobiome, Genevieve Baddoo

Master's Theses

Microbial communities of bacteria, viruses, and fungi form complex interactions in nature. However, our understanding of these communities is limited to those that can be cultured in the lab. Enhanced culture methods have enabled the isolation of numerous fastidious species from urinary tract, definitively proving that the urinary tract of asymptomatic individuals is not sterile. In working with these isolates, our group has observed several instances in which a “purified” isolate actually harbors more than one species. We refer to these additional members as bacterial hitchhikers, a term previously used to describe similar occurrences in soil communities. I hypothesized that …

Dna Methylation Patterns Of Line-1 Elements Specific To Hc21p In Cancer Cells, Dametria Jetters

Master's Theses

Long Interspersed Nuclear Elements (LINEs) are retrotransposons. They function by making a cDNA copy, reverse-transcribing it into DNA and reinserting itself back into the genome; thereby, increasing its copy number. Sequencing of the human genome revealed that LINEs (L1) are underrepresented on the short arm of human chromosome 21 (HC21), but it is enriched in full-length copies. A number of previous studies have investigated the DNA methylation patterns of L1s in cancer cells, but these studies are typically done in euchromatic regions. The heterochromatic short arm of HC21 is primarily composed of heterochromatin. However these regions can be targeted for …

Rapid Radiation Of Zeiformes Revealed Through Comparison Of Jaw Morphologies, Jeffrey Peters

Master's Theses

Zeiformes (e.g., Dories, Lookdown dories, Tinselfishes, Oreos) are a deep (1000 m) to mid-water (100 m) marine order of acanthomorph fishes with a circumpolar distribution, and a fossil record extending back to the Late Cretaceous. The order consists of 33 species across six families. The phylogenetic placement of the Zeiformes within Teleostei has been debated, but more recent studies based on both molecular and morphological data place Zeiforms within Paracanthopterygii closely related to Gadiformes. Zeiformes are characterized by anal and dorsal profiles that contain a variable number of fin rays and spines. They are mostly deep bodied, highly compressed fishes …

Calcium-Mediated Induction Of Vibrio Fischeri Es114 Biofilms, Katia Elizabeth Semenchuk

Master's Theses

Vibrio fischeri bacteria form biofilms that facilitate symbiotic colonization of the Hawaiian bobtail squid, Euprymna scolopes. These host-associated biofilms require production of the SYP polysaccharide. However, it has been difficult to observe robust biofilm formation in vitro in a laboratory setting using wild-type strain ES114; instead, most work investigating syp-dependent biofilm formation has relied on genetically altered strains. Guided by recent findings that increasing calcium induces c-di-GMP (Tischler et al., 2021), a molecule known in other systems to promote biofilm formation, the question was posed as to whether high levels of calcium alone could promote syp-dependent biofilm formation by ES114. …