Molecular Biology Commons^™

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …

Engineering Mesothelin-Binding Proteins As Targeted Cancer Diagnostics And Therapeutics, Allison Rita Sirois

Doctoral Dissertations

Cancer is a significant global health concern; and traditional therapies, including chemotherapeutics, are often simultaneously toxic yet ineffective. There is a critical need to develop targeted cancer therapeutics which specifically inhibit molecules or molecular pathways essential for tumor growth and maintenance. Furthermore, a targeted therapy is only effective when a patient's tumor expresses the molecular target; therefore, companion diagnostics, including molecular imaging agents, are a necessary counterpart of targeted therapies. Mesothelin (MSLN) is a cell surface protein overexpressed in numerous cancers, including triple-negative breast, pancreatic, ovarian, liver, and lung, with limited expression in normal tissues. Aberrant MSLN expression promotes tumor …

Single-Fluorophore Sensors For Mechanical Force In Living Cells, Sarah Kricheff

Honors Scholar Theses

Mechanotransduction is the process by which a mechanical stimulus is converted to a cellular signal. This process is heavily influential of cell morphology, differentiation, and behavior. However, altered levels of mechanical stimuli are also found in many pathological contexts. For example, cancerous cells have stiffer surrounding tissue than healthy cells, and research suggests that this alters cell behavior and promotes metastasis. Despite these findings, the cellular processes behind these signaling alterations remain widely unknown. Understanding these cascades is critical, as involved proteins can give us a deeper understanding of the role of mechanotransduction, and certain proteins can potentially be targeted …

Unconventional Constituents And Shared Molecular Architecture Of The Melanized Cell Wall Of C. Neoformans And Spore Wall Of S. Cerevisiae, Christine Chrissian, Coney Pei-Chin Lin, Emma Camacho, Arturo Casadevall, Aaron M. Neiman, Ruth E. Stark

Publications and Research

The fungal cell wall serves as the interface between the cell and the environment. Fungal cell walls are composed largely of polysaccharides, primarily glucans and chitin, though in many fungi stress-resistant cell types elaborate additional cell wall structures. Here, we use solid-state nuclear magnetic resonance spectroscopy to compare the architecture of cell wall fractions isolated from Saccharomyces cerevisiae spores and Cryptococcus neoformans melanized cells. The specialized cell walls of these two divergent fungi are highly similar in composition. Both use chitosan, the deacetylated derivative of chitin, as a scaffold on which a polyaromatic polymer, dityrosine and melanin, respectively, is assembled. …

Sine Oculis Homeobox Homolog 1 (Six1) Plays A Critical Role In The Progression Of Pulmonary Fibrosis., Cory Wilson

Dissertations & Theses (Open Access)

Idiopathic pulmonary fibrosis (IPF) is the most common idiopathic interstitial pneumonia with a median survival time of 2-4 years after diagnosis. The alarming mortality rate is due to the lack of effective treatments. IPF is a chronic disease that is characterized by alveolar destruction due to increasing extracellular matrix deposition that leads to poor lung compliance, impaired gas exchange, and ultimately respiratory failure. Repetitive alveolar epithelial injury is a central process to the underlying pathology with injury to the type II alveolar epithelial cells (AT2) specifically being a key player in the pathogenesis of IPF. Recent studies have shown that …

Iojap: Morphological And Physiological Phenotype Characterization In Arabidopsis, Thomas Jay Payne

Doctoral Dissertations

IOJAP protein is found in all organisms that contain a ribosome of bacterial origin. The majority of studies suggest that IOJAP plays a role in translation, although this has yet to be thoroughly investigated in plants. Using Arabidopsis thaliana, an extensive phenotype characterization of iojap mutants was performed. Many processes of plant growth were slightly impaired at optimal temperature (22˚C) but became severely hindered at low temperature (12˚C and 4˚C). These cold temperature defects manifested in an overall reduction of plant growth as well as variegation, chlorosis, leaf hyponasty, as well as reduced maximum quantum yield (F_v/F …

Ionic Mechanism Of Lysosomal Function And Cell Metabolism, Jian Xiong

Dissertations & Theses (Open Access)

Two Pore Channels (TPCs) are endolysosomal ion channels that are permeable to sodium and calcium. Defects in TPCs have been implicated to impair vesicle trafficking, autophagy and cell metabolism control; however, the detailed mechanism remains largely unknown. In this study, I show that TPCs are critical for appropriate cargo delivery to the lysosomes and deletion of either TPC1 or TPC2 leads to delayed clearance of autophagosomes, resulting in enlarged lysosomes and accumulated contents inside the lysosomes. Cells with both TPC deleted also exhibit 50% reduction in lysosomal amino acids under normal culture conditions, leading to reduced homeostatic mTORC1 activation.

Glutamine …

P53 Drives A Transcriptional Program That Elicits A Non-Cell-Autonomous Response And Alters Cell State In Vivo, Sydney Moyer

Dissertations & Theses (Open Access)

Cell stress and DNA damage activate the tumor suppressor p53, triggering transcriptional activation of a myriad of target genes. The molecular, morphological, and physiological consequences of this activation remain poorly understood in vivo. We activated a p53 transcriptional program in mice by deletion of Mdm2, a gene which encodes the major p53 inhibitor. By overlaying tissue-specific RNA-sequencing data from pancreas, small intestine, ovary, kidney, and heart with existing p53 ChIP-sequencing, we identified a large repertoire of tissue-specific p53 genes and a common p53 transcriptional signature of seven genes which included Mdm2 but not p21. Global p53 activation …

Calcium Dyshomeostasis In Neurodegeneration, Nicholas Emanuel Karagas

Dissertations & Theses (Open Access)

Neurodegenerative diseases, despite constituting a major and growing cause of mortality globally, have few effective treatments. In order to develop novel therapeutics to combat neurodegeneration, a better understanding of the molecular mechanisms underlying these diseases is needed. Neurons rely on Ca²⁺ to mediate many of their unique functions, and aberrant Ca²⁺ signaling has been broadly implicated in neurodegeneration. The goal of this dissertation is to delineate specific examples of Ca²⁺ dyshomeostasis that I have uncovered in Drosophila models of neurodegeneration.

I first define the role a neurodegeneration-associated mutation plays in perturbing presynaptic [Ca²⁺], which is …

New Mechanisms That Control Fact Histone Chaperone And Transcription-Mediated Genome Stability, Angelo Vincenzo De Vivo Diaz

USF Tampa Graduate Theses and Dissertations

The Role of deubiquitinating enzymes (DUBs) in transcription, replication and genome integrity is not one that has been extensively researched. OTU DUBs are a particular class of enzyme with very little known about them.OTUD5 is a cysteine protease in the OTU family responsible to processing lysine 48 and lysine 63 ubiquitin chains. Recently, it has been implicated in to play a role in transcription through its binding partner UBR5. OTUD5 has also been shown to interact with proteins such as PDCD5 and p53, potentially have great importance in cell fate. In this study, I describe new discovered functions for OTUD5 …

Fine-Tuning Of Alanyl-Trna Synthetase Quality Control Alleviates Global Dysregulation Of The Proteome, Paul Kelly, Arundhati Kavoor, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

One integral step in the transition from a nucleic acid encoded-genome to functional proteins is the aminoacylation of tRNA molecules. To perform this activity, aminoacyl-tRNA synthetases (aaRSs) activate free amino acids in the cell forming an aminoacyl-adenylate before transferring the amino acid on to its cognate tRNA. These newly formed aminoacyl-tRNA (aa-tRNA) can then be used by the ribosome during mRNA decoding. In Escherichia coli, there are twenty aaRSs encoded in the genome, each of which corresponds to one of the twenty proteinogenic amino acids used in translation. Given the shared chemicophysical properties of many amino acids, aaRSs have …

Role Of Ceramide-1 Phosphate In Regulation Of Sphingolipid And Eicosanoid Metabolism In Lung Epithelial Cells, Brittany A. Dudley

USF Tampa Graduate Theses and Dissertations

Ceramide 1-Phosphate (C1P) is a sphingolipid metabolite which plays a large role in inflammation, cell survival and proliferation¹. C1P is known to have both pro- and anti-apoptotic roles in lung cancer cells, governed by ceramide kinase (CERK), upstream of precursor ceramide (Cer)². Previous work reveals C1P serves as the liaison between sphingolipid and eicosanoid synthesis, by decreasing the dissociation rate of group IVA cytosolic PLA₂ (cPLA_2α) from the Golgi membrane, C1P directly activates this phospholipase for downstream eicosanoid synthesis and subsequent inflammatory response³. CERK has been discovered to modulate eicosanoid synthesis, …

Dnajc7, A Molecular Chaperone Protein That Modulates Protein Misfolding In Amyotrophic Lateral Sclerosis (Als), Meaghan Kathleen Stoltz

Electronic Thesis and Dissertation Repository

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease associated with protein misfolding and dysregulated cellular protein quality control mechanisms. Molecular chaperones, and heat shock proteins (Hsp), are key players in maintaining cellular protein quality control. DNAJC7 is an understudied cytosolic Hsp40 that works together with Hsp70 and Hsp90 to regulate proper protein folding or degradation. Of note, mutations in the gene encoding DNAJC7 were discovered to cause familial ALS. We asked whether ALS-associated mutations in DNAJC7 compromise its function as a chaperone, which may cause the toxic accumulation of misfolded proteins. This study attempts to uncover the functions of DNAJC7 …

Sonoporation-Mediated Loading Of Trehalose In Cells For Cryopreservation., Charles W. Shaffer Iv, David F. Grimm, Michael A. Menze, Jonathan A. Kopechek

Undergraduate Research Events

Trehalose, a non-reducing disaccharide, is present in many microorganisms and metazoans. In these organisms, trehalose acts as a stress protectant and helps preserve lipid membranes of cells during states of desiccation and freezing. Trehalose is required on both sides of the cell membrane to achieve a significant cryoprotective effect. Specific loading methods for trehalose are required since this sugar is impermeant to mammalian cells. Trehalose loading in mammalian cells has been achieved by fluid-phase endocytosis and genetic modification for the expression of trehalose transporters, however cryoprotective outcomes are unable to compete with established methods of cryopreservation for mammalian cells. Sonoporation …

Tdp-43 Mediated Blood-Brain Barrier Permeability And Leukocyte Infiltration Promote Neurodegeneration In A Low-Grade Systemic Inflammation Mouse Model, Frank Zamudio, Anjanet R. Loon, Shayna Smeltzer, Khawla Benyamine, Nanda K. Navalpur Shanmugam, Nicholas J. F. Stewart, Daniel C. Lee, Kevin Nash, Maj-Linda B. Selenica

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Neuronal cytoplasmic inclusions containing TAR DNA-binding protein 43 (TDP-43) are a neuropathological feature of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's Disease (AD). Emerging evidence also indicates that systemic inflammation may be a contributor to the pathology progression of these neurodegenerative diseases.

METHODS: To investigate the role of systemic inflammation in the progression of neuronal TDP-43 pathology, AAV9 particles driven by the UCHL1 promoter were delivered to the frontal cortex of wild-type aged mice via intracranial injections to overexpress TDP-43 or green fluorescent protein (GFP) in corticospinal motor neurons. Animals were then subjected …

Characterization Of Mechanotransduction In Annulus Fibrosus Cells, Min Kyu M. Kim

Electronic Thesis and Dissertation Repository

IVD degeneration is a multifactorial pathological process associated with back pain. While biomechanical factors are important regulators of IVD homeostasis, mechanical loading also contribute to the onset of IVD degeneration. Importantly, the mechanotransduction pathways that mediate cell type-specific responses to mechanical loading are not well understood. Transient receptor potential vanilloid 4 (TRPV4) is a multimodally activated cell surface cation channel implicated as a mechanoreceptor regulating the mechano-response in other musculoskeletal cell types. Using both in vitro and in vivo models, the current study aimed to characterize the role of TRPV4 in annulus fibrosus (AF) cell mechanotransduction. Using a mechanically dynamic …

Investigating Chitosan Modified With Triethylammonium Butanamide And Triethylphosphonium Butanamide As Non-Viral Gene Delivery Vectors By Examining Cytotoxicity And Transfection Efficiency, Deborah C. Ehie

MSU Graduate Theses

Gene therapy is a very challenging field, especially with new emerging genetic disorders. Chitosan (CS), due to chitosan’s flexibility, biocompatibility, and biodegradability, has been of interest in the world of gene therapy especially as researchers are gravitating towards non-viral vectors due to the problems caused by viral vectors. Nevertheless, there are still issues regarding solubility, cellular uptake of cargos being transported in vitro or in vivo, increased cytotoxicity levels, as well as many other things that prevent chitosan from being an efficient gene delivery agent. Here I present five derivatives of chitosan, which were all modified with either triethylphosphonium …

Effect Of S100b Deletion On Membrane Properties And Localization Of Ncald And Hpca, Natasha Hesketh

Graduate School of Biomedical Sciences Theses and Dissertations

Calcium signaling is particularly important for neuronal function. Neurons utilize a wide range of calcium-binding proteins. Dysregulation of such proteins is linked to neurodegeneration. Neurocalcin delta (NCALD), hippocalcin (HPCA), and S100B are calcium sensors that are expressed in the hippocampus, a brain region essential to memory and severely damaged in Alzheimer’s disease (AD). Despite the potential importance of these proteins, we do not fully understand the physiological significance of their relationship. Because NCALD and HPCA are known to interact with S100B, we hypothesized that the loss of S100B affects NCALD and HPCA localization, and therefore electrical properties, of hippocampal neurons. …

Artificial Intron Technology To Generate Conditional Knock-Out Mice, Amber N. Thomas-Gordon

Dissertations & Theses (Open Access)

Genetic engineering has been re-shaped by the invention of new tools in modern biotechnology in a way that offers precision and efficiency in modifying the genome at a single nucleotide level and/or allowing precise control of gene expression. Such gene manipulation brings about significant findings and revelations in comprehending more about embryonic development, cellular and physiological functions, and disease pathology. Current methods used to produce conditional knockouts have limitations on conditional allele placement and modification varies among genes in different organisms. Thus, a system for generating conditional alleles with fidelity remains a challenge. My goal was to examine an approach …

Involvement Of Calcium-Dependent Protein Kinases And Phosphatases In Sperm Capacitation-Associated Events, Bidur Paudel

Doctoral Dissertations

ABSTRACT To acquire fertilizing ability, mammalian sperm undergo a series of biochemical and physiological changes collectively known as capacitation^1,2. At the molecular level, capacitation is associated with a fast bicarbonate (HCO₃^-)-dependent activation of a unique type of soluble adenyl cyclase (sAC) and a consequent increase in cyclic AMP (cAMP) levels and PKA activation³. Activation of a cAMP/PKA pathway results in the phosphorylation of PKA substrates, which in turn initiates activation of several signaling cascades ultimately leading to an increase in phosphorylation on tyrosine residues (P-Tyr) of sperm axonemal proteins^4,5. Increase in …

Dissecting The Cellular Control Of Septin Organization In A Global Cereal Killer, Nawaraj Dulal

Graduate Theses and Dissertations

Rice blast disease, caused by the filamentous fungus Magnaporthe oryzae, destroys sufficient rice each year to feed 60 million people, and is a serious threat to global food security. A wheat-adapted lineage of M. oryzae now poses threat to global wheat production. Rice blast disease is currently controlled using limited fungicides, and the emergence of fungicide resistance within M. oryzae populations is a growing concern. There is a pressing need to identify new classes of fungicides to control the disease, which requires better understanding of the basic biology of the pathogen. To establish disease, M. oryzae forms a specialized dome …

Secretion Of Proteins And Antibody Fragments From Transiently Transfected Endothelial Progenitor Cells, Loree Heller, Reynald Thinard, Melanie Chevalier, Sezgi Arpag, Yu Jing, Ruth Greferath, Richard Heller, Claude Nicolau

Bioelectrics Publications

In neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and amyotrophic lateral sclerosis, neuroinflammation can lead to blood-brain barrier (BBB) breakdown. After intravenous or intra-arterial injection into mice, endothelial progenitor cells (EPCs) home to the damaged BBB to promote neurovascular repair. Autologous EPCs transfected to express specific therapeutic proteins offer an innovative therapeutic option. Here, we demonstrate that EPC transfection by electroporation with plasmids encoding the reporter protein GFP or an anti-beta-amyloid antibody fragment (Fab) leads to secretion of each protein. We also demonstrate the secreted anti-beta-amyloid Fab protein functions in beta-amyloid aggregate solubilization.

Mechanistic And Translational Studies On Skeletal Malignancies, Jeremy Mcguire

USF Tampa Graduate Theses and Dissertations

New treatment strategies are desperately needed for treating skeletal malignancy. Skeletal malignancies can be either primary cancer that originated in the bone, such as osteosarcoma, or metastatic cancer that spread from another organ to the skeleton, as in the case of breast or prostate cancer. In this thesis, I will detail two projects that focus on the discovery of new treatment strategies for both primary skeletal malignancy and metastatic skeletal malignancy.

The first project focuses on the primary skeletal malignancy, osteosarcoma, a rare cancer that is commonly diagnosed in children and young adults and metastasizes to the lungs. The survival …

The Amino Terminal Domains Of Sheep Cx46 Or Cx50 Determine Their Gap Junction Channel Open Stability And Unitary Channel Conductance, Benny Yue

Electronic Thesis and Dissertation Repository

Connexins form intercellular communication channels known as gap junctions (GJs), which are found throughout the vertebrate species. GJs formed by different connexins harbor unique channel properties that have not been fully defined. High-resolution structures of native Cx46 and Cx50 GJs from sheep (sCx46 and sCx50) were recently resolved. Molecular dynamics studies identified the NT domains, especially the 9^th position, as key determinants in the differences of energetic barrier to K⁺ permeation in sCx46 and sCx50 GJs. We studied functional properties of GJs formed by sCx46, sCx50, NT domain swapped chimeras (sCx46-50NT and sCx50-46NT), and point variants at the …

Insights Into Desiccation Tolerance: Properties Of Late Embryogenesis Abundant Proteins From Embryos Of Artemia Franciscana, Blase Matthew Leblanc

LSU Doctoral Dissertations

LEA proteins are a family of intrinsically disordered proteins that are expressed in various life stages of anhydrobiotic organisms and have been strongly associated with survival during water stress. The brine shrimp Artemia franciscana is the only known anhydrobiotic animal that expresses LEA proteins from Groups 1, 3, and 6. Here, I report that AfrLEA6, a novel Group 6 LEA protein, is most highly expressed in embryos during diapause and decreases throughout pre-emergence development. Notably, there is an acute drop in expression upon termination of the diapause state and the titer of AfrLEA6 during diapause is 10-fold lower than values …

Probing The Limits Of Singular Gene Expression Through The Activity Of High Representation Odorant Receptor Transgenes, Eugene Lempert

Dissertations, Theses, and Capstone Projects

Singular gene expression is a common phenomenon in biology, making its appearance in immunoglobulin selection, protocadherin expression, X chromosome-inactivation, random monoallelic expression, and olfactory receptor choice. Singularity involves an activation and a feedback step. The mechanisms of singular gene choice have some capacity to integrate additional member genes while still maintaining singularity, but will activate an additional member if an earlier choice was incapable of triggering the feedback step. Odorant Receptor (OR) genes are substantially divergent from each other in terms of coding sequence, promoter structure, and genomic locus, all of which plays a role in how many Olfactory Sensory …

Dictyostelium Discoideum Protein Kinase C-Orthologue Pkca Regulates The Actin Cytoskeleton Through Interaction With Phospholipase D And P21-Activated Kinase, Sean Singh

Dissertations, Theses, and Capstone Projects

Proper regulation of the actin cytoskeleton is crucial to many cellular processes. Many of these processes are regulated by extracellular signaling cues, which direct changes in the actin cytoskeleton, resulting in changes to cellular morphology, and directed motility. The social amoeba, Dictyostelium discoideum, is used as a simple model system to study the translation of extracellular signals to the actin cytoskeleton. When starved, these unicellular amoebae undergo a multicellular developmental process characterized by a tightly regulated sequence of signaling events. This results in chemotaxis and formation of a multicellular aggregate, and ultimately cell differentiation and the formation of a fruiting …

Mutagenesis Of The Btea Gene Encoding A Bordetella Virulence Protein, Xiaolei Mao

2020 Symposium Posters

Bordetella Type III Secretion System Effector A (BteA) is a virulence protein found in members of the genus Bordetella which include important pathogens of humans and other mammals. Bordetella pertussis is a causative agent of the whooping cough, a highly contagious respiratory disease that is especially dangerous, and sometimes deadly, for infants. The BteA protein appears to be an important factor in the ability of these pathogens to cause disease, as it leads to rapid killing of a wide range of mammalian cells. The aim of this project is to determine which regions of the DNA are important for mediating …

The Impact Of Age/Rage Signaling On Oxidative Stress Under Diabetic Conditions In Cardiac Fibroblasts, Christopher Dorroh

Honors Theses

Diabetes is a major health concern in the United States, with 1.5 million new cases diagnosed each year. Patients who suffer from diabetes have an increased risk of developing heart failure, a form of cardiovascular disease. Heart failure has been shown to result from increased left ventricular stiffness, which in turn is caused by increased remodeling of the extracellular matrix (ECM). This increase in ECM remodeling is a result of AGE/RAGE signaling, which occurs at a heightened level in the cardiac fibroblast cells of diabetics. Studies have shown that diabetics have elevated levels of AGEs (Advanced Glycation End-Products), which bind …

Investigating The Redox Sensitivity Of Mitf Splice Variants, Rachel Berryman

Senior Theses

Within pigment-producing cells known as melanocytes, the transcription factor MITF is intimately involved in regulating genes associated with cell cycle maintenance and melanocyte differentiation. Research, however, has provided conflicting results on the relationship between the expression levels of MITF and melanocyte cell fate. To complicate matters, two splice variants of MITF exist, differing by only 18 base pairs. These variants have been observed at variable levels of expression in melanocyte and melanoma cells, raising the question as to their functional purpose. Building upon previous research by the Leachman/Cassidy lab that identified the redox sensitivity of MITF while additionally establishing a …