Biochemistry, Biophysics, and Structural Biology Commons^™

Characterization Of Ape1 And Dna G-Quadruplex Interaction In Transcription Regulation And Dna Damage Repair, Suravi Pramanik

Theses & Dissertations

Human AP Endonuclease 1 (APE1) is the primary enzyme in the base excision repair (BER) pathway that repairs apurinic/apyrimidinic (AP) sites, the most frequently formed DNA lesions in the genome. Recently, through genome-wide mapping analysis, we have shown that APE1, as well as its post-translationally modified form, acetylated APE1 (AcAPE1), is enriched in the gene regulatory regions. The APE1/AcAPE1-enriched regions also harbor Guanine (G)-rich sequences that fold into DNA secondary structures called G-quadruplexes (G4s). Our lab has demonstrated a strong genome-wide correlation between the occurrence of G4 structures and the binding of APE1 and AcAPE1. However, it is unknown whether …

The Role Of Parkin In Mitochondrial Dna, Eliezer Lichter

Theses & Dissertations

Mitochondria are at the center of biological phenomena such as aging and diseases, especially neurodegenerative diseases. While the discovery of mitochondria only came approximately 200 years after the cell was discovered, a lot of progress has been made since. The mitochondrial genome encodes proteins vital for mitochondrial function. These proteins are only a subset of the proteins present in mitochondria; the rest are nuclear encoded. The nucleus also encodes cytosolic proteins vital for mitochondrial maintenance. One of these is Parkin, an E3 ubiquitin ligase that ubiquitinates mitochondrial proteins as mitochondria become depolarized. Its activity has been shown to be involved …

Lpa Disruption With Aav-Crispr Potently Lowers Plasma Apo(A) In Transgenic Mouse Model: A Proof-Of-Concept Study, Alexandria M Doerfler, So Hyun Park, Julia M Assini, Amer Youssef, Lavanya Saxena, Adam B Yaseen, Marco De Giorgi, Marcel Chuecos, Ayrea E Hurley, Ang Li, Santica M Marcovina, Gang Bao, Michael B Boffa, Marlys L Koschinsky, William R Lagor

Faculty, Staff and Students Publications

Lipoprotein(a) (Lp(a)) represents a unique subclass of circulating lipoprotein particles and consists of an apolipoprotein(a) (apo(a)) molecule covalently bound to apolipoprotein B-100. The metabolism of Lp(a) particles is distinct from that of low-density lipoprotein (LDL) cholesterol, and currently approved lipid-lowering drugs do not provide substantial reductions in Lp(a), a causal risk factor for cardiovascular disease. Somatic genome editing has the potential to be a one-time therapy for individuals with extremely high Lp(a). We generated an LPA transgenic mouse model expressing apo(a) of physiologically relevant size. Adeno-associated virus (AAV) vector delivery of CRISPR-Cas9 was used to disrupt the LPA transgene in …

Caribbean Reef-Building Coral-Symbiodiniaceae Network: Identifying Symbioses Critical For System Stability In A Changing Climate, Shaman Patel

All HCAS Student Capstones, Theses, and Dissertations

Increasing global ocean temperatures and frequency of marine heatwaves pose dire consequences for coral reefs. High temperatures often lead to disruptions in coral symbiosis resulting in coral bleaching, increasing the mortality of corals. However, corals can potentially avoid bleaching peril by associating with thermally tolerant symbionts. Here we provide a tool for understanding symbiosis network stability of Caribbean reef-building corals. We created a network of Caribbean hermatypic corals and their associated Symbiodiniaceae phylotypes. A bleaching model was applied to this network to test for resilience and robustness (R50) to thermal stress. It was also layered with trait data for coral …

Dpc29 Promotes Mitochondrial Translation Post-Initation In Saccharomyces Cerevisiae, Kyle Andrew Hubble

Graduate School of Biomedical Sciences Theses and Dissertations

Although the cytosolic and bacterial translation systems are well studied, much less is known about translation in mitochondria. In the yeast Saccharomyces cerevisiae, mitochondrial gene expression is predominately regulated by translational activators. These regulators are thought to promote translation by binding the elongated 5’-UTRs on their target mRNAs. Since mammalian mitochondrial mRNAs generally lack 5’-UTRs, they must regulate translation by other mechanisms. As expected, most yeast translational activators lack orthologues in mammals. Recently, a mitochondrial gene-specific translational activator, TACO1, was reported in mice and humans. To better define its role in mitochondrial translation I examined the yeast TACO1 orthologue, DPC29. …

Successful Use Of Continuous Erector Spinae Plane Blocks In A Patient With Variant Angina After Large Ventral Hernia Repair, Alexandra L Belfar, Yi Deng, Raymond C Yu, Annas Sabbagh

Faculty, Staff and Students Publications

Coronary artery spasm constitutes the primary underlying pathology of variant angina. Because provocation of coronary artery spasm may occur with both excess sympathetic and excess parasympathetic stimulation, patients with this disorder have extremely limited options for perioperative pain control. This is especially true for procedures involving extensive abdominal incision/manipulation. Whereas neuraxial analgesia might otherwise be appropriate in these cases, several studies have demonstrated that coronary artery spasm can occur as a result of epidural placement, and therefore, that this may not be an optimal choice for patients with variant angina. This report discusses the case of a patient with a …

Lord Of The Z-Rings: Uncovering The Role Of Mraz And Ftsl In Bacillus Subtilis Cell Division, Maria Louise White

USF Tampa Graduate Theses and Dissertations

Cell division is a complex and highly orchestrated process that requires careful coordination. The process of cell division in prokaryotes primarily occurs via binary fission, where one mother cell becomes two genetically identically and equally sized daughter cells. In most bacteria a key protein, FtsZ, forms a FtsZ ring (Z-ring) to mark the division site and recruit proteins involved in cytokinesis. Whilst much has been learned about the contents and assembly of the divisome in model organisms such as Escherichia coli and Bacillus subtilis factors governing the regulation of divisome are much more poorly understood. …

Radiation Exposure Determination In A Secure, Cloud-Based Online Environment, Ben C. Shirley, Eliseos J. Mucaki, Peter Rogan

Biochemistry Publications

Rapid sample processing and interpretation of estimated exposures will be critical for triaging exposed individuals after a major radiation incident. The dicentric chromosome (DC) assay assesses absorbed radiation using metaphase cells from blood. The Automated Dicentric Chromosome Identifier and Dose Estimator System (ADCI) identifies DCs and determines radiation doses. This study aimed to broaden accessibility and speed of this system, while protecting data and software integrity. ADCI Online is a secure web-streaming platform accessible worldwide from local servers. Cloud-based systems containing data and software are separated until they are linked for radiation exposure estimation. Dose estimates are identical to ADCI …

Ngly1 Deficiency Affects Glycosaminoglycan Biosynthesis And Wnt Signaling Pathway In Mice, Amy Batten

PANDION: The Osprey Journal of Research and Ideas

Individuals affected by NGLY1 Deficiency cannot properly deglycosylate and recycle certain proteins. Even though less than 100 people worldwide have been diagnosed with this rare autosomal recessive condition, thousands are affected by similar glycosylation disorders. Common phenotypic manifestations of NGLY1 Deficiency include severe neural and intellectual delay, impaired muscle and liver function, and seizures that may become intractable. Very little is currently known about the various mechanisms through which NGLY1 deficiency affects the body and this has led to a lack of viable treatment options for those afflicted. This experiment uses a loss-of-function (LOF) mouse model of NGLY1 Deficiency homologous …

Cell-Intrinsic Melanin Fails To Protect Melanocytes From Ultraviolet-Mutagenesis In The Absence Of Epidermal Melanin, Tirzah J. Weiss, Emma R. Crawford, Valentina Posada, Hafeez Rahman, Tong Liu, Brandon M. Murphy, Tiffany E. Arnold, Shannon Gray, Zhexuan Hu, Rebecca C. Hennessey, Lianbo Yu, John August D'Orazio, Craig J. Burd, Jonathan H. Zippin, Douglas Grossman, Christin E. Burd

Markey Cancer Center Faculty Publications

Melanin is a free-radical scavenger, antioxidant, and broadband absorber of ultraviolet (UV) radiation which protects the skin from environmental carcinogenesis. However, melanin synthesis and UV-induced reactive melanin species are also implicated in melanocyte genotoxicity. Here, we attempted to reconcile these disparate functions of melanin using a UVB- sensitive, NRAS-mutant mouse model, TpN. We crossed TpN mice heterozygous for an inactivating mutation in Tyrosinase to produce albino and black littermates on a C57BL/6J background. These animals were then exposed to a single UVB dose on postnatal day three when keratinocytes in the skin have yet to be melanized. Approximately one-third (35%) …

Novel Therapeutic Strategies For Alzheimer’S Disease: Prostaglandin D2 Signaling And Its Human Polymorphisms As Well As A Polypharmacological Approach, Charles H. Wallace

Dissertations, Theses, and Capstone Projects

Alzheimer’s disease (AD) is an age related neurodegenerative disease with pathology that includes amyloid plaques, neurofibrillary tangles and non-resolving neuroinflammation. Non-resolving neuroinflammation lasts the entire course of the disease and has deleterious effects and is often thought to accelerate AD pathology. Non-Steroidal Anti-inflammatory Drugs (NSAIDs) have commonly been used as therapeutics to treat pain, inflammation and vascular. NSAIDs work by altering the cyclooxygenase (COX) mediated biosynthesis of prostaglandins which are lipid mediators that have many physiological functions, for example nociception, inflammation and vasodilation. Epidemiological studies support the notion that NSAIDs could be used to treat AD. Yet, clinical trials using …

Redundancy And Developmental Coordination In Myxococcus Xanthus: Insights From The Phenome, Jessica A. Comstock

Dissertations - ALL

Genotype-to-phenotype mapping can typically involve disrupting the function of a gene and observing the impact of mutation on phenotype. While this can be a powerful tool for uncovering gene function, complicating factors such as influences between genes and the environment, epistatic interactions with other genes, and genetic redundancy could all potentially mask the phenotype of a mutation such that functional inferences cannot be made. On the level of the single gene, this may not be particularly informative, but it is possible that studying phenotype in this way at a genome scale might allow for the observation of patterns between genes …

Identification And Characterization Of Genetic Elements That Regulate A C-Di-Gmp Mediated Multicellular Trait In Pseudomonas Fluorescens, Collin Kessler

Electronic Theses and Dissertations

Microbial communities contain densely packed cells where competition for space and resources are fierce. These communities are generally referred to as biofilms and provide advantages to individual cells against immunological and antimicrobial intervention, dehydration, and predation. High intracellular pools of cyclic diguanylate monophosphate (c-di-GMP) cause cells to aggregate during biofilm formation through the production of diverse extracellular polymers. Genes that encode c-di-GMP catalytic enzymes are commonly mutated during chronic infections where opportunists display enhanced resistance to phagocytosis and antibiotics. Our lab uses an emergent multicellular trait in the model organism Pseudomonas fluorescens Pf0-1 to study the emergence of c-di-GMP mutations …

Ewing Sarcoma Transcriptome: Identification Of Foxn3 As A Novel Target Of Ews-Fli1, Natasha Kreiling

Theses & Dissertations

Ewing Sarcoma is an aggressive cancer characterized by a fusion gene formed from a chromosomal translocation between a RNA binding protein and a transcription factor. The most common fusion gene is EWS-FLI1 a potent oncogenic transcription factor responsible for initiating genome instability. EWS-FLI1 promotes tumor growth by dysregulating several genes and pathways. We have identified FOXN3, an important gene in cell cycle control and development, as being suppressed by EWS-FLI1. In the future, a better understanding of FOXN3 and its ability to act as a tumor suppressor in EWS will unravel novel mechanisms of EWS pathogenesis, potential biomarker and drug …

Dual Mechanisms Implemented By Lin-28 For Positive Regulation Of Hbl-1 Are Necessary For Proper Development Of Distinct Tissues In Caenorhabditis Elegans, Madeleine Minutillo

Graduate School of Biomedical Sciences Theses and Dissertations

In Caenorhabditis elegans, the heterochronic pathway is comprised of a hierarchy of genes that control the proper timing of developmental events. hbl-1 (Hunchback Like-1) encodes an Ikaros family zinc-finger transcription factor that promotes the L2 stage cell fate events of the hypodermis. The downregulation ofhbl-1 is a crucial step for the transition from the L2 to the L3 stage. There are two known processes through which negative regulation of hbl-1 occurs: suppression of hbl-1 expression by 3 let-7 miRNAs through the hbl-1 3’UTR and inhibition of HBL-1 activity by LIN-46. The mechanisms by which hbl-1 is positively regulated have not …

The Effects Of Stress On The Mammalian Nucleolus And Ribosome Synthesis, Russell T. Sapio

Graduate School of Biomedical Sciences Theses and Dissertations

Ribosomes are responsible for translating every protein in the cell and are essential in all domains of life. Ribosome biosynthesis (RB) takes place in the nucleolus and is an intricate hierarchical process involving over 200 factors, including ribosomal proteins, ribosomal RNA (rRNA), and trans-acting ribosome biogenesis factors (RBFs). Inhibiting RB can disrupt nucleolar integrity, causing ribosomal- and nucleolar-factors to delocalize. This can stabilize the transcription factor p53, which is normally degraded rapidly, ultimately causing cell cycle arrest or apoptosis, through a mechanism termed the nucleolar stress response (NSR). This thesis explores the effects of inhibiting RB post rRNA transcription and …

Investigating Granulopoiesis Of Neutrophils From Myeloblasts In The Bone Marrow Post Novel Anti-Schistosoma Compound Treatment, Sarah Alsuleiman, Paul Davis

Theses/Capstones/Creative Projects

Schistosomiasis, a commonly neglected tropical disease, is a waterborne parasitic worm infection able to infect through direct skin penetration. This disease affects approximately 270 million people worldwide and ranks only second to malaria as a leading infectious disease. Although some possible alternatives are emerging, currently, the most effective drug treatment is praziquantel (PZQ). However, PZQ is only effective against the adult stage of the worm, allowing juvenile worms to progress in the infection. Additionally, Schistosoma worms are developing resistance to this drug as reduced efficacy has been noted. Thus, the need for drug discovery and testing is increased. SA01, a …

Validation Of Whole Genome Resequencing For Mapping The Genetics Of Ascites In Broilers And Viral Susceptibility In Layers, Katherine Pepper Lee

Graduate Theses and Dissertations

This dissertation focused on the efficacy and validity of whole genome resequencing (WGR) for fine mapping genetic determinants of particular traits in a given organism. Previously, our research group used WGR to identify haplotype blocks of single nucleotide polymorphisms associated with ascites resistance with some as strong candidates for use in marker-assisted selection (MAS). Chapter 2 discusses the completion of a MAS project through evaluation of ascites incidence as well as production traits of economic value to poultry producers. Thus, the MAS project also covered viability of this methodology in the industry. The MAS significantly reduced ascites incidence in broilers …

Investigating The Biorisk Of Genetically Engineered Thermosynechococcus Elongatus Bp1, Cherrelle Leah Barnes

Chemistry & Biochemistry Theses & Dissertations

Cyanobacteria, also known as blue-green algae, are an ancient group of microorganisms that use simple materials, such as sunlight, carbon dioxide and water, to produce energy while providing oxygen to the atmosphere by performing photosynthesis. Synthetic biology approaches have been employed with cyanobacteria as a platform to produce a range of products, such as biofuels, by inserting a series of genes into the cyanobacterial genome that will allow the conversion of metabolic intermediates to such desired products. Although these methods are promising, it is important to understand any potential bio-risk they pose. This research evaluates the potential bio-risk of genetically …

Characterization Of Genetic Pathways Involved In Resistance To A Novel Antifungal Peptide, Kayla L. Haberman

Graduate Theses and Dissertations

Antibiotic resistance is increasing prevalence, particularly in Candida glabrata. This opportunistic pathogen is closely phylogenetically related to Saccharomyces cerevisiae; however, its characterization is limited. C. glabrata is only second to Candida albicans as a fungal pathogen in immunocompromised patients. Commonly resistant to azoles, the most common fungal therapy, it has become costly and challenging to treat. A histatin 5 derived antifungal peptide, KM29, has a high degree of efficacy in Candida species and S. cerevisiae. The objective of this work is to advance our understanding of the mechanism of action of KM29 against C. glabrata. Previous work in the lab …

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …

Investigating The Biochemical Properties Of A Novel Mutation, A194v, In Human Rad51, Briana Vollbeer

All Theses

DNA double-strand breaks (DSB) are one of the most serious DNA lesions because improper repair of a DSB can lead to loss of heterozygosity, aneuploidy, and cancer. One of the primary pathways to repair DSBs is homologous recombination (HR). HR resects the DNA around the DSB and then uses homologous DNA as a template to restore the broken sequence. RAD51 has a vital function in this pathway by forming a nucleoprotein filament on a resected end of the DSB. The nucleoprotein filament searches for homology within the homologous DNA. Once homology is located, strand invasion followed by strand exchange occurs. …

Modeling Electrostatics In Molecular Biology And Its Relevance With Molecular Mechanisms Of Diseases, Mahesh Koirala

All Dissertations

Electrostatics plays an essential role in molecular biology. Modeling electrostatics in molecular biology is complicated due to the water phase, mobile ions, and irregularly shaped inhomogeneous biological macromolecules. This dissertation presents the popular DelPhi package that solves PBE and delivers the electrostatic potential distribution of biomolecules. We used the newly developed DelPhiForce steered Molecular Dynamics (DFMD) approach to model the binding of barstar to barnase and demonstrated that the first-principles method could also model the binding. This dissertation also reflects the use of existing computational approaches to model the effects of Single Amino Acid Variations (SAVs) to reveal molecular mechanisms …

Heat Stress Response And Excystation In Entamoeba Histolytica, Irem Bastuzel

All Dissertations

Entamoeba histolytica is a water- and food-borne intestinal protozoan parasite that causes amoebiasis and liver abscess and is responsible for symptomatic disease in approximately 100 million people each year leading to ~ 100,000 deaths. The most common disease transmission follows the oral-fecal route, but it can also be transmitted by mechanical vectors such as animals carrying the amoeba from contaminated sources to water systems. In rare cases, disease transmission has been recorded in some patients in which men-to-men sexual practices were preferred.

The life cycle of E. histolytica starts through ingestion of infectious cysts, which are non-dividing, quadri-nucleated structures surrounded …

Identification Of Genomic, Proteomic, And Metabolomic Signatures Associated With Pulmonary Hypertension Syndrome In Broilers, Duaa Almansaf

Graduate Theses and Dissertations

The present dissertation contains a collection of studies that examine the genomic, proteomic, and metabolomic association to pulmonary hypertension or ascites phenotype in fast-growing broilers. Pulmonary hypertension is a multifactorial metabolic disease influenced by physiological, environmental, and nutritional factors. It is characterized by a number of structural changes including, thrombosis and adverse pulmonary vascular remodeling. Thus, the atrial pressure is increased, and the right ventricle becomes hypertrophied, resulting in heart failure and the death of the bird. Pulmonary hypertension or ascites is a global problem that has negatively impacted the economy. The increased mortality rate of broilers (25%) is estimated …

Extracellular Domain Of Pept1 Interacts With Tm1 To Facilitate Substrate Transport, Jiemin Shen, Miaohui Hu, Xiao Fan, Zhenning Ren, Corinne Portioli, Xiuwen Yan, Mingqiang Rong, Ming Zhou

Faculty, Staff and Students Publications

Mammalian peptide transporters, PepT1 and PepT2, mediate uptake of small peptides and are essential for their absorption. PepT also mediates absorption of many drugs and prodrugs to enhance their bioavailability. PepT has twelve transmembrane (TM) helices that fold into an N-terminal domain (NTD, TM1–6) and a C-terminal domain (CTD, TM7–12), and has a large extracellular domain (ECD) between TM9–10. It is well-recognized that peptide transport requires movements of the NTD and CTD, but the role of the ECD in PepT1 remains unclear. Here we report the structure of horse PepT1 encircled in lipid nanodiscs and captured in the inward-open apo …

Increasing The Resilience Of Plant Immunity To A Warming Climate, Jong Hum Kim, Christian Castroverde, Shuai Huang, Chao Li, Richard Hilleary, Adam Seroka, Reza Sohrabi, Diana Medina-Yerena, Bethany Huot, Jie Wang, Sharon Marr, Mary Wildermuth, Tao Chen, John Macmicking, Sheng Yang He

Biology Faculty Publications

Extreme weather conditions associated with climate change affect many aspects of plant and animal life, including the response to infectious diseases. Production of salicylic acid (SA), a central plant defence hormone, is particularly vulnerable to suppression by short periods of hot weather above the normal plant growth temperature range via an unknown mechanism. Here we show that suppression of SA production in Arabidopsis thaliana at 28 °C is independent of PHYTOCHROME B (phyB) and EARLY FLOWERING 3 (ELF3), which regulate thermo-responsive plant growth and development. Instead, we found that formation of GUANYLATE BINDING PROTEIN-LIKE 3 (GBPL3) defence-activated biomolecular condensates (GDACs) …

Decoding The Pitx2-Controlled Genetic Network In Atrial Fibrillation, Jeffrey D Steimle, Francisco J Grisanti Canozo, Minjun Park, Zachary A Kadow, Md Abul Hassan Samee, James F Martin

Faculty, Staff and Students Publications

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia and a major risk factor for stroke, often arises through ectopic electrical impulses derived from the pulmonary veins (PVs). Sequence variants in enhancers controlling expression of the transcription factor PITX2, which is expressed in the cardiomyocytes (CMs) of the PV and left atrium (LA), have been implicated in AF predisposition. Single nuclei multiomic profiling of RNA and analysis of chromatin accessibility combined with spectral clustering uncovered distinct PV- and LA-enriched CM cell states. Pitx2-mutant PV and LA CMs exhibited gene expression changes consistent with cardiac dysfunction through cell type-distinct, PITX2-directed, cis-regulatory …

Symmetry-Inspired Analysis Of Biological Networks, Ian Leifer

Dissertations, Theses, and Capstone Projects

The description of a complex system like gene regulation of a cell or a brain of an animal in terms of the dynamics of each individual element is an insurmountable task due to the complexity of interactions and the scores of associated parameters. Recent decades brought about the description of these systems that employs network models. In such models the entire system is represented by a graph encapsulating a set of independently functioning objects and their interactions. This creates a level of abstraction that makes the analysis of such large scale system possible. Common practice is to draw conclusions about …

Cdc6 Is Sequentially Regulated By Pp2a-Cdc55, Cdc14, And Sic1 For Origin Licensing In S. Cerevisiae, Jasmin Philip

Dissertations, Theses, and Capstone Projects

Control of DNA replication is critical for progression of the cell cycle and genomic stability. Cyclin-dependent kinases (CDKs) coordinate numerous phosphorylation events to accomplish two biological tasks for all living organisms: DNA replication and cell division. One CDK, Cyclin-Cdc28, is responsible for cell cycle progression in budding yeast. DNA replication requires a stepwise assembly of the pre-replicative complex on DNA, including Orc1-6, Cdc6, Cdt1 and Mcm2-7, during M-G1 phase. Cdc6 contains eight Cdc28 consensus sites, SP or TP motifs. Clb5-Cdc28 phosphorylates Cdc6-T7 to recruit Cks1, the Cdc28 phospho-adaptor, for subsequent multisite phosphorylation during S phase. There are two phospho-degrons at …