Life Sciences Commons^™

Light And Temperature Entrainment Of Two Circadian-Driven Behaviors In The Flesh Fly Sarcophaga Crassipalpis, Raven Ragsdale

Electronic Theses and Dissertations

Circadian rhythms dictate the timing of both once-in-a-lifetime adult emergence (eclosion) and daily locomotor activity rhythms in the flesh fly S. crassipalpis. Light cycles are considered the primary environmental time cue (zeitgeber), but the life history of S. crassipalpis suggests that temperature cycles (thermocycles) may also play a key role. This work evaluates the efficacy of thermocycling as a zeitgeber in S. crassipalpis. We found that shifting both light and temperature cycles of sufficient amplitude affect the phasing of eclosion and locomotor activity, but result in different patterns. Additional experiments suggest greater thermocycle sensitivity during the late metamorphic …

Establishing The Efficacy Of Non-Cellular Components Of Adipose-Derived Stromal Vascular Fraction In Promoting Angiogenesis., Daniel Benson

Electronic Theses and Dissertations

Microvascular disease is hallmarked by pathophysiological conditions such as endothelial senescence, intimal thickening which impairs vasodilation, and regression of the capillary beds causing tissue ischemia in the myocardium or in peripheral vascular networks. Adipose-derived stromal vascular fraction (SVF) has previously demonstrated the ability to revascularize tissue. Increasing evidence shows that regenerative cells elicit their therapeutic benefit by paracrine mechanisms, leaving open extracellular vesicles (EVs) as a potential crux of the cell therapy paradigm. To test this idea, three types of gelatin methacrylate hydrogels were employed: SVF gels, EV gels derived from SVF, and blank control gels, which were used in-vitro …

Telomerase Reverse Transcriptase Marks A Novel Population Of Adult Stem Cells In The Mouse Brain That Respond To Metabolic Interventions By Modulating Adult Brain Plasticity, Gabriel S. Jensen

Electronic Theses and Dissertations

Telomerase reverse transcriptase (TERT) is expressed by quiescent adult stem cells (qASC) in numerous adult murine and human tissues but has never been explored in the adult brain. Here, these data demonstrate that TERT+ cells in the adult mouse brain represent a novel population of multipotent qASCs. TERT+ cells were localized to numerous classical neuro/gliogenic niches including the ventricular-subventricular zone, hypothalamus and olfactory bulb, as well as newly discovered regions of adult tissue plasticity such as the meninges and choroid plexus. TERT+ cells expressed neural stem cell markers such as Nestin and Sox2, but not markers of activated stem/progenitor cells, …

Determination Of The Functional Role Of Rab-Ggt In Physcomitrium Patens., Hyun Jin Jung

Electronic Theses and Dissertations

Protein prenylation, a common lipid post-translational modification, is required for growth and development in eukaryotes. Rab geranylgeranylation involves the addition of one or two 20-carbon geranylgeranyl moieties to Rab-GTPase target proteins, which regulate intracellular vesicle trafficking. The reaction is carried out by heterodimeric Rab geranylgeranyltransferase (Rab-GGT), which is composed of two associated α- and β-subunits, with the assistance of an additional protein called Rab escort protein (REP). Loss of function of the Rab-GGT α subunit RGTA1 has not been reported in any plant. While knockout of either of the two β subunits RGTB1 or RGTB2 results in …

A Computational Model Of The Line-1 Retrotransposon Life Cycle And Visualization Of Metabolic Networks In 3-Dimensions., Michael D. Martin

Electronic Theses and Dissertations

Computational modeling of metabolic reactions and cellular systems is evolving as a tool for quantitative prediction of metabolic parameters and reaction pathway analysis. In this work, the basics of computational cell biology are presented as well as a summary of physical processes within the cell, and the algorithmic methods used to find time dependent solutions. Protein-protein and enzyme-substrate interactions are mathematically represented via mass action kinetics to construct sets of linear differential equations that describe reaction rates and formation of protein complexes. Using mass action methods, examples of reaction networks and their solutions are presented within the Virtual Cell simulation …

Primary Cilia Of The Cardiac Neural Crest & Hedgehog-Mediated Mechanisms Of Congenital Heart Disease, Lindsey A. Fitzsimons

Electronic Theses and Dissertations

Elimination of primary cilia in cardiac neural crest cell (CNCC) progenitors is hypothesized to cause a variety of congenital heart defects (CHDs), including atrioventricular septal defects, and malformations of the developing cardiac outflow tract. We present an in vivo model of CHD resulting from the conditional elimination of primary cilia from CNCC using multiple, Wnt1:Cre-loxP, neural crest-specific systems, targeting two distinctive, but critical, primary cilia structural genes: Intraflagellar transport protein 88 (Ift88) or kinesin family member 3A (Kif3a). CNCC loss of primary cilia leads to widespread CHD, where homozygous mutant embryos (MUT) display a variety of outflow tract malformations, septation …

Functional Role Of Ppal And Potential For Moss In Industrial Applications., Susana Perez Martinez

Electronic Theses and Dissertations

This dissertation is an examination and characterization of the functional roles of PPAL. PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) is a recently discovered gene. PPAL homologs are present in all plants and many animals, where its function is largely unknown. It is possible that PPAL could participate in prenylation processes since it shares similarity to the α subunits of known prenylation enzymes. Prenylation is a post-translational modification of proteins that involves the addition of a lipid moiety to proteins to facilitate membrane targeting and association and promote protein-protein interactions. Prenylation has important roles in plant growth and development, including …

Role Of Galactose, Thiazolidinediones, And Neet Proteins In Mitochondrial Physiology And Therapeutic Development., Robert Anthony Skolik

Electronic Theses and Dissertations

This dissertation explores the relationship between mitochondrial physiology and development of therapeutics. Mitochondrial dysfunction is associated with both acute and chronic forms of pathophysiology. This work aims to address development efforts at the cell culture and drug-target levels with respect to mitochondria. At the cell culture level, I characterize an approach that has been shown to improve the physiological dependency on mitochondria in tumor-derived cells. I demonstrate that prolonged replacement of glucose with galactose in culture medium induces a global metabolic shift in hepatocellular carcinoma (HepG2) cells to closer reflect a primary hepatocyte phenotype (Chapter 2). I characterize this shift …

The Roles Of Pon2 In Mitochondrial Physiology, Lung Tumor Cell Proliferation, And Lung Tumorigenesis., Aaron Whitt

Electronic Theses and Dissertations

Paraoxonase 2 (PON2) is an intracellular, multifunctional enzyme with near-ubiquitous tissue distribution. Within cells, PON2 is localized to mitochondria and endoplasmic reticulum (ER), where it mitigates the formation of reactive oxygen species (ROS). PON2’s chief enzymatic function is its lactonase activity, through which it catalyzes the hydrolysis of a bacterial quorum-sensing molecule, N-(3-oxododecanoyl)-l-homoserine lactone (C12), effectively disrupting bacterial intercellular communication and protecting against infection. C12 is produced by the opportunistic pathogen Pseudomonas aeruginosa and has been shown to disrupt various aspects of eukaryotic host cell physiology and evoke apoptotic cell death through the activity of PON2. Additionally, PON2 has garnered …

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …

The Pathophysiological Mechanisms Of Alzheimer's Disease; Investigating Therapeutic Interventions For Disease Onset, Alexandra A. Sandberg

Electronic Theses and Dissertations

Alzheimer’s Disease is a multifarious disease that progressively affects more people as both the proportion of older adults in the population and life expectancy increase in both the United States and worldwide. This devastating disease is a result of rampant neuronal loss in the memory centers of the brain that robs the independence of those who are diagnosed and places a heavy burden on those who care for them. Traditionally speaking, research has focused on the hallmark pathology of amyloid plaques, targeting them to try and prevent disease onset. However, countless failures in clinical trials aimed at this said pathology …

The Role Of Ehd2 In Endothelial Cells, Rachael Judson

Electronic Theses and Dissertations

The role of EHD2 in terms of Cav1 interaction had not been previously characterized and was the main goal of this research. Cav1 has been shown to lead to the ubiquitination of Rac1. Because of this, the role of EHD2 in Rac1 regulation was investigated. An increase in long-term migration in endothelial cells was observed and suggested that EHD2 impacts the RhoA pathway instead of the Rac1 pathway. This lead to the hypothesis that EHD2 controls a part of the RhoA pathway. This hypothesis is supported by the loss of filamentous actin and an increase in serrated junctions in cells …

Organellar Zn2+ Homeostasis And The Role Of Trpml Channels In Neuronal Lysosome Physiology And Axonal Transport, Taylor Franklin Minckley

Electronic Theses and Dissertations

Zinc (Zn²⁺) is crucial for proper cellular function, and as such it is important to measure and track Zn²⁺ dynamics in living cells. Fluorescent sensors have been used to estimate Zn²⁺ content of subcellular compartments, but little is known about endolysosomal Zn2+ homeostasis. Similarly, although numerous sensors have been reported, it is unclear whether and how Zn²⁺ can be released from intracellular compartments into the cytosol due to a lack of probes that can detect physiological dynamics of cytosolic Zn²⁺. My dissertation started with comparing and characterizing different Zn²⁺ sensors including the …

Inhibition Of De Novo And The Prion-Like Spread Of Amyloidogenesis Using In Vitro And In Vivo Disease Models, Johnson Anazoba Joseph

Electronic Theses and Dissertations

The aberrant fibrous, extracellular, and intracellular proteinaceous deposits in cells, organs and tissues are referred to as amyloids. These deposits are dominated by β-sheet structures that have been implicated in several neurodegenerative diseases and cancer. In this work, the types of amyloidosis studied include Parkinson’s disease (PD) using UA196 and NL5901 strains of Caenorhabditis elegans (C. elegans), Alzheimer’s disease (AD) using GMC101 strain of C. elegans, and cancer-associated mutant p53 aggregation in MIA PaCa-2 mutant cells. Several molecules including SK-129, NS132, NS163, bexarotene, a polyphenol (-)-epi-gallocatechine gallate (EGCG), ADH40, RD148, and RD242 were screened in vitro and in …

Antioxidant Biomarkers And Nutraceutical Therapeutics In Neurodegeneration And Neurotrauma, Lilia A. Koza

Electronic Theses and Dissertations

Mild traumatic brain injury (mTBI), yielding a Glascow Coma Scale of 13-15, is the most commonly occurring severity of TBI. Pathology from mTBI consists of blood brain barrier disruption, neuroinflammation, oxidative stress, excitotoxicity, mitochondrial dysfunction, protein aggregation, axonal degeneration, and resulting neuronal death. These processes deplete the body’s endogenous antioxidant system. We report a retrospective analysis of antioxidant blood biomarkers in patients with a history of mTBI from a local sports medicine clinic, Resilience Code. We found persistent sex-specific antioxidant depletions in mTBI patients associated with worsened symptomology.

Certain populations, such as athletes, are at high risk for repetitive mTBI …

Identifying Adp-Ribosylation As The Biochemical Signal That Marks Dna-Protein Crosslinks For Sprtn-Dependent Proteolysis, Katelyn Hurley

Electronic Theses and Dissertations

DNA-protein crosslinks (DPCs) form when proteins covalently attach to DNA. It is estimated that hundreds of DPCs form in our cells each day. Because these lesions are cytotoxic, mammalian cells have evolved multiple intricate repair systems to remove DPCs and restore genome integrity. One mechanism mammalian cells rely on for DPC repair is direct proteolysis by the metalloprotease, SPRTN. While it is known that SPRTN degrades a heterogenous array of DPCs, including both naturally occurring and chemically induced, how SPRTN selects DPCs amongst chromatin-associated proteins remains unknown. Our main objective is to determine how DPC repair is regulated. In Chapter …

Characterizing The Lir Domain Of Abin1 And Identifying Its Role As A Regulator Of Mitophagy, Andrew Rhiner

Electronic Theses and Dissertations

A20 Inhibitor of NF-κB (ABIN1/TNIP1) is a known regulator of TNFα signaling induced cell death and inflammation. The regulatory activity has been attributed to ABIN1’s recruitment of the ubiquitin editing enzyme TNF-α-induced protein 3 (TNFAIP3/A20) to Receptor-interacting serine/threonine-protein kinase 1 (RIPK1). The regulation of RIPK1 by ABIN1 and A20 relies on a third player, linear ubiquitin chain assembly complex (LUBAC), which is involved in the recruitment of ABIN1 to RIPK1. Loss of LUBAC or ABIN1 is embryonic lethal, but loss of A20 is not embryonic lethal. The embryonic lethality due to loss of ABIN1, paired with the lack of lethality …

Development Of Novel Pyridazine Derivatives And Drug Delivery Systems Against Dengue, Janae A. Culmer

Electronic Theses and Dissertations

The lack of approved vaccines, medications and treatment regimens has significantly contributed to the rapid spread of mosquito-borne viruses such as Dengue and Zika virus. The complex immunopathology of these viruses presents limitations for the development and implementation of a definitive, safe and effective approach to combat infections.Previous research has demonstrated that vector control strategies such as the elimination of larval habitats, larviciding with insecticides, the use of biological agents and the application of adulticides have been unsuccessful in the reduction of viral transmission leading to the need for the continued development of antivirals. This research proposes an approach for …