Other Biochemistry, Biophysics, and Structural Biology Commons^™

Towards The Development Of A Maga Reporter Gene Expression Construct For Magnetic Resonance Imaging, Karina Quiaoit

Electronic Thesis and Dissertation Repository

Development of methods to monitor cellular activity with magnetic resonance imaging (MRI) provides a powerful tool for studying disease progression and monitoring therapy. This thesis investigates components necessary for development of reporter gene expression for MRI, to track Nkx2.5 transcription factor activity during tumour growth and, in the future, to calibrate MR contrast against a well-known optical reporter gene, like firefly luciferase. In human MCF-7 breast cancer cells, Nkx2.5 is induced by all-trans retinoic acid (tRA) and activates a minimal promoter of the rat sodium iodide symporter (rNISmin) gene. Here, we used firefly luciferase reporter gene expression to examine a …

Shifting The Stress Curve: Using "Stress Inoculation" And Exercise To Promote Resilience, Mikyung Kim

Master's Theses

Problem

Stress influences an organism’s physiological systems via an inverted u-shaped curve: An optimum amount of stress will optimize body functions, but too little stress or too much stress for long periods of time can impair body functions. Researchers have been very interested in exploring the mechanisms that may “delay the tipping point” between the positive and negative effects of stress. A rightward shift in the stress curve would allow one to maintain optimal performance even at higher or more prolonged stress levels. The molecular and cellular mechanisms that underlie this rightward shift could result in resilience, clinically defined as …

Expression Analysis Of A Glucose Oxidase Transgene In Tobacco, Jordan Burt

Honors Theses

Glucose oxidase (GOX) is an enzyme in plants that catalyzes the oxidation of glucose to hydrogen peroxide and Glucono delta-lactone[5]. We have expressed GOX under the control of an estrogen inducible system, XVE, to analyze the gene's expression under this system compared to a system using the 35s system. The 35s system contains a promoter that constitutively turns on the GOX gene in the Nicotiana tabacum plant which causes the gene to always be turned on. Leaf disc assays were performed with discs from 35s, XVE, and also wild type plants (not containing the GOX gene) in order to extract …

Computer Simulations Of Enzymes, Jianzhuang Yao

Doctoral Dissertations

Enzymes are important catalysts in living systems, and understanding catalytic mechanisms of enzymes is an important task for modern biophysics and biochemistry. Computer simulations have emerged as very useful tools for understanding how enzymes work. In this dissertation, QM/MM MD simulations were applied to study the catalytic mechanisms of several enzymes, including sedolisin, S-adenosyl-L-methionine (AdoMet)-dependent methyltransferases, and salicylic acid binding protein 2. For sedolisin, we focus on the acylation and deacylation reactions catalyzed by the enzymes. We proposed a general acid/base mechanism involving the Glu/Asp residues at the active site. MD and QM/MM free energy simulations on pro-kumamolisin show that …

Comparative Genomics Of Microbial Chemoreceptor Sequence, Structure, And Function, Aaron Daniel Fleetwood

Doctoral Dissertations

Microbial chemotaxis receptors (chemoreceptors) are complex proteins that sense the external environment and signal for flagella-mediated motility, serving as the GPS of the cell. In order to sense a myriad of physicochemical signals and adapt to diverse environmental niches, sensory regions of chemoreceptors are frenetically duplicated, mutated, or lost. Conversely, the chemoreceptor signaling region is a highly conserved protein domain. Extreme conservation of this domain is necessary because it determines very specific helical secondary, tertiary, and quaternary structures of the protein while simultaneously choreographing a network of interactions with the adaptor protein CheW and the histidine kinase CheA. This dichotomous …

Applications And Improvements In The Molecular Modeling Of Protein And Ligand Interactions, Jason Bret Harris

Doctoral Dissertations

Understanding protein and ligand interactions is fundamental to treat disease and avoid toxicity in biological organisms. Molecular modeling is a helpful but imperfect tool used in computer-aided toxicology and drug discovery. In this work, molecular docking and structural informatics have been integrated with other modeling methods and physical experiments to better understand and improve predictions for protein and ligand interactions. Results presented as part of this research include:

1.) an application of single-protein docking for an intermediate state structure, specifically, modeling an intermediate state structure of alpha-1-antitrypsin and using the resulting model to virtually screen for chemical inhibitors that can …

Acceleration And Verification Of Virtual High-Throughput Multiconformer Docking, Sally Rose Ellingson

Doctoral Dissertations

The work in this dissertation explores the use of massive computational power available through modern supercomputers as a virtual laboratory to aid drug discovery. As of November 2013, Tianhe-2, the fastest supercomputer in the world, has a theoretical performance peak of 54,902 TFlop/s or nearly 55 thousand trillion calculations per second. The Titan supercomputer located at Oak Ridge National Laboratory has 560,640 computing cores that can work in parallel to solve scientific problems. In order to harness this computational power to assist in drug discovery, tools are developed to aid in the preparation and analysis of high-throughput virtual docking screens, …

Natural Phenomena As Potential Influence On Social And Political Behavior: The Earth’S Magnetic Field, Jackie R. East

Theses and Dissertations--Political Science

Researchers use natural phenomena in a number of disciplines to help explain human behavioral outcomes. Research regarding the potential effects of magnetic fields on animal and human behavior indicates that fields could influence outcomes of interest to social scientists. Tests so far have been limited in scope. This work is a preliminary evaluation of whether the earth’s magnetic field influences human behavior it examines the baseline relationship exhibited between geomagnetic readings and a host of social and political outcomes. The emphasis on breadth of topical coverage in these statistical trials, rather than on depth of development for any one model, …

Biochemical Assay Optimization And Computational Screening Efforts To Identify Potential Luxs Inhibitors, Keeshia Q. Wang

Master's Theses

Quorum sensing (QS) is a process of coordination of bacterial gene expression in response to cell population. System two QS is regulated by the small signaling molecule autoinducer-2 (AI-2) and is implicated in the infectious behaviors of various bacterial species. AI-2 is biosynthesized from S-ribosylhomocysteine (SRH) by the enzyme LuxS and induces interspecies cell-to-cell communication. Inhibition of LuxS would therefore inhibit interspecies QS. Herein, a search for novel molecular species that will competitively bind with SRH in the LuxS binding site is performed in silico. Computational screening results are then validated in vitro using an optimized LuxS inhibition …

Soybean Nodulin 26: A Channel For Water And Ammonia At The Symbiotic Interface Of Legumes And Nitrogen-Fixing Rhizobia Bacteria, Jin Ha Hwang

Doctoral Dissertations

During the infection and nodulation of legume roots by soil bacteria of the Rhizobiaceae family, the invading endosymbiont becomes enclosed within a specialized nitrogen-fixing organelle known as the "symbiosome". In mature nodules the host infected cells are occupied by thousands of symbiosomes, which constitute the major organelle within this specialized cell type. The symbiosome membrane is the outer boundary of this organelle which controls the transport of metabolites between the symbiont and the plant host. These transport activities include the efflux of the primary metabolic product of nitrogen fixation and the uptake of dicarboxylates as an energy source to support …

Regulation Of Actin Dynamics During Drosophila Germband Extension, Ashley M. Motlong

Electronic Theses and Dissertations

Convergent extension is a process that occurs in the development of a wide variety of organisms, including gastrulation in the Drosophila embryo to begin to lay out the adult body plan. In fly embryos, this is known as germband extension and is mainly driven by cell intercalation or neighbor exchange by planar polarized cell-cell interface contraction to shorten the tissue along the dorsal-ventral axis. In this thesis, I show that interface contraction consists of phases of fast interface shortening and intervals of stable interface size. My data also suggests that regulation of F-actin aggregates at these shrinking interfaces is important …

Human Equilibrative Nucleoside Transporter Subtype 1: Structure-Function Analysis Using Cysteine Mutagenesis And Thiol Modifying Techniques, Jamie Park

Electronic Thesis and Dissertation Repository

Human equilibrative nucleoside transporter 1 is the main mediator of bi-directional nucleoside flux and is found ubiquitously. Inhibitor and substrate interactions with ENT1 are known to be affected by cysteine-modifying reagents. Our aim was to investigate the importance of cysteine residues in hENT1 function and identify which residues were sensitive to thiol modification for further application of cysteine scanning mutagenesis on extracellular loop 5. Transporter function was assessed by the binding of [³H]NBMPR and the cellular uptake of [³H]2-chloroadenosine. Treatment of hENT1 with the neutral sulfhydryl-modifier methyl methanethiosulfonate (MMTS) enhanced [³H]NBMPR binding but decreased …

Does Vibrational Loading Modulate The Effects Of Radiotherapy On Growing Bone?, Samantha Hay

Honors Capstone Projects - All

Radiotherapy is an important part of cancer therapy, used in addition to surgery for treatment of patients with soft tissue sarcomas, and alternatively for treatment of patients with Ewing sarcoma of bone. Treating pediatric extremity tumors with radiotherapy has been shown to have harmful effects on the epiphyseal plate, resulting in permanent limb shortening and deformity when bone growth centers are exposed to radiation. Mechanical signals, specifically low-magnitude high-frequency vibrations (LMHFV), have been shown to be non-invasive and non-pharmacological growth factors in bone that have the potential to serve as a safe treatment for a number of clinical conditions. Thus, …

Recombinant Expression And Purification Of Human Intrinsic Factor (If) And Mutants K159d And Q201a Designed To Interfere With Cubilin Receptor Binding, Soreen Cyphers

Honors Capstone Projects - All

Although both the α- and β-domains of intrinsic factor (IF) have been previously expressed, the full crystal structure of the protein has yet to be reported. The purpose of this research is to (1) express IF in order to obtain a complete crystal structure and (2) utilize a mutant form of IF in order to orally deliver rotavirus to the ileum.The first goal of this research is to express IF in the yeast Pichia pastoris. The second goal is to express a K159D IF mutant protein. K159 of IF plays a role in salt bridge formation between IF and …

Toxicological Assessment Of Intra‐Tracheal Instilled Nanoceria On Kidneys Of Sprague‐Dawley Rats, Geeta Nandyala

Theses, Dissertations and Capstones

Recent studies suggest that use of nanoceria in industry is associated with increased risk of human and environmental exposure. How inhaled nanoceria might affect the kidneys is not yet known. To investigate this possibility, Sprague Dawley rats were exposed to a single dose of 7mg/kg body weight cerium oxide nanoparticles by intratracheal instillation. Animals were sacrificed at day 1, 3, 14, or 28 days after exposure and the kidneys collected for histological and biochemical analysis. No significant difference was observed in kidney to body weight ratio between the different groups. Hematoxylin and eosin staining did not reveal any significant changes …

A Hydrodynamic Method For Measuring Aqueous Nanoparticle Surface Interactions, Kellen John Sorauf

Electronic Theses and Dissertations

The objectives of this research dissertation were to develop and present novel analytical methods for the quantification of surface binding interactions between aqueous nanoparticles and water-soluble organic solutes. Quantification of nanoparticle surface interactions are presented in this work as association constants where the solutes have interacted with the surface of the nanoparticles. By understanding these nanoparticle-solute interactions, in part through association constants, the scientific community will better understand how organic drugs and nanomaterials interact in the environment, as well as to understand their eventual environmental fate. The biological community, pharmaceutical, and consumer product industries also have vested interests in nanoparticle-drug …

Dissecting The Interaction Between P53 And Trim24, Aundrietta D. Duncan

Dissertations & Theses (Open Access)

Dissecting the Interaction of p53 and TRIM24

Aundrietta DeVan Duncan

Supervisory Professor, Michelle Barton, Ph.D.

p53, the “guardian of the genome”, plays an important role in multiple biological processes including cell cycle, angiogenesis, DNA repair and apoptosis. Because it is mutated in over 50% of cancers, p53 has been widely studied in established cancer cell lines. However, little is known about the function of p53 in a normal cell. We focused on characterizing p53 in normal cells and during differentiation. Our lab recently identified a novel binding partner of p53, Tripartite Motif 24 protein (TRIM24). TRIM24 is a member of …

Recombinant Production Of Vitronectin And Insights Into Its Structure And Role In Fibrinolysis, Cameron T. Landers

Chancellor’s Honors Program Projects

No abstract provided.

Identification Of Regions Responsible For The Open Conformation Of S100a10 Using Chimaeric S100a11/S100a10 Proteins, Liliana Santamaria-Kisiel

Electronic Thesis and Dissertation Repository

S100A11 is a dimeric, EF-hand calcium-binding protein. Calcium binding to S100A11 results in a large conformational change that uncovers a broad hydrophobic surface used to interact with phospholipid-binding proteins (annexins A1 and A2), and facilitate membrane vesiculation events. In contrast to other S100 proteins, S100A10 is unable to bind calcium due to deletion and substitution of calcium-ligating residues. Despite this, calcium-free S100A10 assumes an “open” conformation that is very similar to S100A11 in its calcium-bound state (Ca2+-S100A11). To understand how S100A10 is able to adopt an open conformation in the absence of calcium, seven chimeric proteins were constructed where regions …

Development Of An Electrochemical Technique For Oxidative Surface Mapping To Investigate Solution-Phase Protein Dynamics With High Performance Mass Spectrometry And Advanced Informatics, Carlee Suzanne Patterson Mcclintock

Doctoral Dissertations

Oxidative protein surface mapping has gained popularity over recent years within the mass spectrometry (MS) community for gleaning information about the solvent accessibility of folded protein structures. The hydroxyl radical targets a wide breadth of reactive amino acids with a stable mass tag that withstands subsequent MS analysis. A variety of techniques exist for generating hydroxyl radicals, with most requiring sources of radiation or caustic oxidizing reagents. The purpose of this research was to evaluate the novel use of electrochemistry for accomplishing a comparable probe of protein structure with a more accessible tool. Two different working electrode types were tested …

Altered Phosphorylation Of [Beta]-Catenin In Glucocorticoid Treated 235-1 Rat Pituitary Tumor Cells, Susie K. Saunders

Theses, Dissertations and Capstones

Beta-catenin is an essential cell adhesion and signaling protein, associated with high prolactin levels in rat pituitary tumor cells. It has been shown that phosphorylation affects the location and activity of b-catenin. Glycogen synthase kinase (GSK3-b) is a serine-threonine kinase that phosphorylates b-catenin on N-terminal residues, targeting it for proteasomal degradation. Studies have shown that C-terminal tyrosine phosphorylation decreases the association of b-catenin with cadherin. In 235-1 rat pituitary tumor cells, our lab has shown that the glucocorticoid analog dexamethasone (Dex) decreases the half- life of b-catenin while increasing the activity of GSK3-b. The current study was undertaken to examine …

Diet And Growth Of Larval And Juvenile Grass Pickerel, Esox Americanus Vermiculatus, And Central Mudminnow, Umbra Limi, In The Green Bottom Wildlife Management Area, Cabell County, West Virginia, Erica Midkiff

Theses, Dissertations and Capstones

The grass pickerel, Esox americanus vermiculatus, is listed as Undetermined on the Vertebrate Species List of Concern in West Virginia. The central mudminnow, Umbra limi, is a disjunct population in Green Bottom Swamp. The lentic, vegetated areas that are required for spawning for the grass pickerel and the central mudminnow have been reduced by residential, agricultural, and industrial developments. Green Bottom Swamp, a naturally occurring wetland of 58 ha, and a nearby mitigated wetland of 29 ha, provides spawning habitat for the grass pickerel and the mudminnow. Fishes were collected in beds of Potamogetan crispus and Ceratophyllum demursum …

Regulation Of The Expression Of Hmn-Sod At The Level Of The Mitochondrial Processing Of Precursor Hmn-Sod, Gary Leslie Wright

Theses, Dissertations and Capstones

The mitochondrion imports and processes the vast majority of the proteins which comprise its structural elements and metabolic pathways. Studies in the last decade have been successful at defining the mechanism and protein machinery responsible for recognizing, importing, and processing cytosolic precursor proteins into the mature mitochondrial proteins. Little is known, however, about physiological factors which might influence or compromise mitochondrial protein processing. The objective of this work was to develop a novel approach to study mitochondrial import and assembly of precursor proteins as a process within the context of the cellular environment. To these ends we employed the baculovirus …