Biochemistry, Biophysics, and Structural Biology Commons^™

A Biophysical Study Of The Ion Transport Mechanism In Uncoupling Protein 2 By Investigating The Role Of Lysine Residues In Its Matrix Network, Stephanie O. Uwumarenogie

Theses and Dissertations (Comprehensive)

ABSTRACT

Uncoupling protein 2 (UCP2) is one of five UCP homologues found in the inner mitochondrial membrane that transports protons from the intermembrane space to the mitochondrial matrix. In turn, the proton motive force is dissipated and less ATP is produced in the mitochondria. UCP2 is proposed to influence insulin secretion in type II diabetes, and decrease the amount of reactive oxygen species produced in the mitochondria, however the detailed mechanism of ion (proton and anions) transport in UCP2 and other UCP homologues are not fully understood. Sequence alignment analysis performed on proteins in the mitochondrial carrier family (MCF) including …

Akap150 Dynamics In Anterior Pituitary Cells, Kristen E. Dew

Electronic Theses and Dissertations

Cellular communication occurs as a result of changes in signaling pathways. A well-studied signaling pathway is through G protein coupled receptors (GPCRs). In gonadotropes, GPCR stimulation by GnRH leads to the activation of protein kinase A (PKA). Activated PKA can phosphorylate ion channels, potentially causing an influx of calcium, depolarization and secretion of hormones. A scaffolding protein known as AKAP150 anchors PKA near L-type calcium channels. In addition, AKAP150 anchors phosphatases, which provides temporal control during signaling events. It was recently shown that AKAP150 is mobile in neuronal dendrites, providing regulation to where the signaling cascade occurs in the cell. …

Novel Cell Penetrating Peptide-Adaptors Effect Intracellular Delivery And Endosomal Escape Of Protein Cargos, John C. Salerno, Verra M. Ngwa, Scott J. Nowak, Carol A. Chrestensen, Allison N. Healey, Jonathan L. Mcmurry

Faculty Articles

The use of cell penetrating peptides (CPPs) as biomolecular delivery vehicles holds great promise for therapeutic and other applications, but development has been stymied by poor delivery and lack of endosomal escape. We have developed a CPP-adaptor system capable of efficient intracellular delivery and endosomal escape of user-defined protein cargos. The cell penetrating sequence of HIV transactivator of transcription was fused to calmodulin, which binds with subnanomolar affinity to proteins containing a calmodulin binding site. Our strategy has tremendous advantage over prior CPP technologies because it utilizes high affinity noncovalent, but reversible coupling between CPP and cargo. Three different cargo …

Mitochondrial Function Assessed By 31p Mrs And Bold Mri In Non-Obese Type 2 Diabetic Rats, Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu

Electrical & Computer Engineering Faculty Publications

The study aims to characterize age-associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia-reperfusion in the skeletal muscle of the Goto-Kakizaki (GK) rats, a rat model of non-obese type 2 diabetes (T2D). ³¹P magnetic resonance spectroscopy (MRS) and blood oxygen level-dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. ³¹P-MRS and BOLD-MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation. The time constant of phosphocreatine recovery, an index of mitochondrial oxidative capacity, …

The Role Of Oxidative Stress In The Mechanisms Of Ammonia-Induced Brain Swelling And Tolerance In The Goldfish (Carassius Auratus), David F. Jones Lisser Mr.

Theses and Dissertations (Comprehensive)

Toxic build-ups of ammonia can cause potentially fatal brain swelling in mammals, but such swelling is reversible in the anoxia- and ammonia-tolerant goldfish (Carassius auratus). The mechanisms of ammonia-induced brain swelling and tolerance remain elusive, but several studies have suggested a role for reactive oxygen species (ROS), which may damage proteins and lipids in the plasma membrane of astrocytes in the brain. As a result, osmotic gradients across cell membranes may be altered leading to water uptake by astrocytes and swelling. While a role for ROS has been proposed in mammals, no studies have addressed this question in …

Epigenetic Response To Habitat Change: Changes Variation In Dna Methylation Frequencies And Generational Transmission Vary With Invasion Status, Aaron W. Schrey, Travis R. Robbins, Jacob D. Lee, David W. Dukes, Alexandria K. Ragsdale, Christopher J. Thawley, Tracy Langkilde

Biology: Faculty Publications

Epigenetic mechanisms may be important for a native species’ response to rapid environmental change. Red Imported Fire Ants (Solenopsis invicta Santschi, 1916) were recently introduced to areas occupied by the Eastern Fence Lizard (Sceloporus undulatus Bosc & Daudin, 1801). Behavioral, morphological and physiological phenotypes of the Eastern Fence Lizard have changed following invasion, creating a natural biological system to investigate environmentally induced epigenetic changes. We tested for variation in DNA methylation patterns in Eastern Fence Lizard populations associated with different histories of invasion by Red Imported Fire Ants. At methylation sensitive amplified fragment length polymorphism loci, we detected a higher …

The Uyghur Population And Genetic Susceptibility To Type 2 Diabetes: Potential Role For Variants In Capn10, Apm1 And Fut6 Genes, Feifei Zhao, Dolikun Mamatyusupu, Youxin Wang, Honghong Fang, Hao Wang, Qing Gao, Hao Dong, Siqi Ge, Xinwei Yu, Jie Zhang, Lijuan Wu, Manshu Song, Wei Wang

Research outputs 2014 to 2021

Genome-wide association studies have successfully identified over 70 loci associated with the risk of type 2 diabetes mellitus (T2DM) in multiple populations of European ancestry. However, the risk attributable to an individual variant is modest and does not yet provide convincing evidence for clinical utility. Association between these established genetic variants and T2DM in general populations is hitherto understudied in the isolated populations, such as the Uyghurs, resident in Hetian, far southern Xinjiang Uyghur Autonomous Region, China. In this case–control study, we genotyped 13 single-nucleotide polymorphisms (SNPs) at 10 genes associated with diabetes in 130 cases with T2DM and 135 …

Superior Inhibitory Control And Resistance To Mental Fatigue In Professional Road Cyclists, Kristy Martin, Walter Staiano, Paolo Mensaspa, Tom Hennessey, Samuele M. Marcora, Richard J. Keegan, Kevin G. Thompson, David T. Martin, Shona R. Halson, Ben Rattray

Research outputs 2014 to 2021

Purpose:

Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists.

Methods:

After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control) for 30 min (mental exertion condition), or an easy cognitive task for 10 min (control condition) in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time …

Effect Of Quantum Dots, Novel Biological Imaging Agents, In Liver Cells In Vitro, Utshaha Maharjan

All Master's Theses

The use of Quantum dots (QDs) coated with polymer and functionalized with carboxylic acid groups in medical applications are explored. Their water solubility and exceptional stability in aqueous environments make them potentially useful for such applications as imaging and ligand attachments. However, there are concerns regarding the toxic effects of QDs and the minimal dose that can be used without producing any detrimental effects to organisms. In this study, QDs coated with the amphiphilic polymer coating tri-n-octylphosphine oxide and poly (maleic anhydride-alt-1-tetradecene (TOPO-PMAT)) which is functionalized with carboxylic acid groups were used to investigate their toxic effect in mouse liver …

Confirmation Of Emx2 Protein Binding Partners, Cody Gillman

All Master's Theses

The neocortex is a structure within mammalian brains that processes sensory input from eyes, ears, and touch receptors and mediates the conscious use of skeletal muscles. The processing of information related to each of these types of functions is localized within discrete areas of the neocortex, which are separated by sharp borders. Proper development of these functional areas is regulated during embryogenesis by several transcription factors that are expressed in distinct gradients across the progenitor layer of the neocortex, the ventricular zone. Despite the vast amount of progress that has been made in describing how these transcription factors impact the …

Small Molecule Disruption Of Ros-Regulating Pathways In Human Carcinoma, Rebecca E. Mccall

College of Graduate Studies: Theses & Dissertations

Gold (I) coordinated N-heterocyclic carbenes containing appended redox cycling moieties were designed and analyzed for their ability to target the antioxidant network via multiple mechanisms in various human cancer cell models. Complexes containing either ferrocene or naphthoquinone redox cycling moieties were screened for inhibition of cell growth, inhibition of thioredoxin reductase (TrxR), and accentuation of exogenous ROS. The cell death pathway employed was determined by flow cytometry via detection of Annexin-V FITC. Furthermore, differential gene expression between treated cells and untreated cells revealed the induction of endoplasmic reticulum stress and unfolded protein response pathways.

Computational Studies Of Paradifluorobenzene Cations And Hydrogen Cyanide Molecule, John C. Rowe Iv

Honors Theses

Polycyclic aromatic hydrocarbons (PAHs) are hypothesized to comprise a significant portion of interstellar carbon identified from the Diffuse Interstellar Bands (DIBs). Gas phase cation-molecule reactions between compounds that previously existed as weakly bound species provides the best explanation for the emergence of PAHs in the interstellar medium (ISM). In this work, we use computational methods to characterize one of these weakly-bound systems. We discovered that intramolecular charge distribution (calculated using the Natural Population Analysis) dictate the complexes formed between a paradifluorobenzene cation and either one or two HCN molecules. Additionally, the relative stabilities of the complexes and the binding energies …

Characterization Of Catecholamine Receptors And Transporters In Murine Macrophages, Elizabeth Gonye

Honors Theses

Macrophages are a critical part of the immune response. When circulating monocytes move into tissues they differentiate int macrophages to mount the first line of defense against pathogens.

Calcium (Ii) Catalyzed Nitrone Additions, Elizabeth A. Congdon

Honors Theses

Calcium(II) complexes have be shown to be successful catalysts for nitrone reactions. The addition of n-­‐methyl and n-­‐phenyl nitrones to donor-­‐acceptor cyclopropanes was achieved with calcium triflate (Ca(OTf). Differentially substituted tetrahydro-­‐1,2-­‐oxazines were synthesized in good to excellent yields. Calcium triflate was also found to catalyze the addition of silyl enol ethers to n-­‐phenyl nitrones along the Mukaiyama-­‐Mannich addition pathway. B-­‐amino carbonyls were synthesized from a variety of substituted nitrones. Bulky and cyclic silyl enol ethers were also found to be reactive, the products of which were isolated in good to excellent yields.

Impact Of Vector Range Expansion On Pathogen Transmission Dynamics Of Lyme Disease In Southwestern Virginia, Bishan Bhattarai

Honors Theses

Blacklegged ticks, Ixodes scapularis is the primary vector of Lyme disease in eastern United States. Borrelia Burgdorfei, the etiological agent of Lyme disease is transferred by ticks of Ixodes species. In recent years, its congener, Ixodes affinis has been expanding its range northwards from its southern population. We were interested in studying how the introduction of this new vector affected the interaction between the pathogen genotype and the host. We hypothesized that differential host use by I. affinis and I. scapularis would partly explain observed differences in B. burgdorferi infection prevalence and genotypic structure in southeastern Virginia. The result …

Pluralistic And Stochastic Gene Regulation: Examples, Models And Consistent Theory, Elisa N. Salas, Jiang Shu, Matyas F. Cserhati, Donald P. Weeks, Istvan Ladunga

Department of Biochemistry: Faculty Publications

We present a theory of pluralistic and stochastic gene regulation. To bridge the gap between empirical studies and mathematical models, we integrate pre-existing observations with our meta-analyses of the ENCODE ChIP-Seq experiments. Earlier evidence includes fluctuations in levels, location, activity, and binding of transcription factors, variable DNA motifs, and bursts in gene expression. Stochastic regulation is also indicated by frequently subdued effects of knockout mutants of regulators, their evolutionary losses/gains and massive rewiring of regulatory sites. We report wide-spread pluralistic regulation in ≈800 000 tightly co-expressed pairs of diverse human genes. Typically, half of ≈50 observed regulators bind to both …

A Chiroptical Molecular Sensor For Ferrocene, Marco Agnes, Andrea Nitti, Douglas A. Vander Griend, Daniele Dondi

University Faculty Publications and Creative Works

A homochiral, square-shaped, D2 symmetrical nanosized metal-linked macrocycle is able to form stable complexes with ferrocene in polar solvents, with detection achieved by means of multiple outputs (optical/chiroptical spectroscopies and cyclic voltammetry). Selective sensing using chiroptical spectroscopy in the presence of interfering analytes is demonstrated.

Structure And Biological Activity Of A D3g Mutation In The Human Mitochondrial Chaperonin Hsp60, Jihui Li

Open Access Theses & Dissertations

Proteins are essential components in all cellular activities, including signal transduction, gene expression regulation, immune response, structural support and many others. Following their synThesis on the ribosome, proteins need to fold into their precise three-dimensional structure to obtain functionality. If they fold incorrectly they are prone to aggregation and cause a wide range of neurodegenerative diseases. Some proteins are capable of folding without assistance but others need help from protein complexes known as chaperonins. Chaperonins are a family of proteins that assemble into barrel-shaped cages the create a protected chamber for misfolded proteins to refold into their biologically active state. …

Investigation Of Dna Interaction With Bis-Cationic Imidazolium Salts, Kyle Daily 6440928

Williams Honors College, Honors Research Projects

Imidazolium salt compounds have shown promise in vitro against non-small cell lung cancer (NSCLC) lines, but the exact mechanism of activity these compounds is still unknown. Due to their planar aromatic structure, we hypothesized that our bis-cation imidazolium salt series could act through DNA intercalation similar to known intercalators ethidium bromide, acridine orange, and echinomycin. Here, we tested bis-cation imidazolium salts with linkers of 2, 4, 10, and 12 carbons for DNA intercalation via viscosity and fluorescent intercalator displacement (FID) assays. Despite some solubility issues that may have decreased results, we found that our butyl and dodecyl linked compounds had …

Lipid-Protein Interactions Via Fluorescence Quenching In Small Unilamellar Vesicles, Talia Kordahi

Williams Honors College, Honors Research Projects

Studying peptide interactions with model membranes have aided in understanding protein-lipid interactions more clearly. In this report, fluorescent small unilamellar vesicles (SUVs) of a known composition were made. Two peptides, RND1 and MARCKS, were also fluorescently labeled and added to a solution of SUVs. The interactions between these were observed via fluorescence quenching, read out with a spectrofluorimeter. In addition, two environments of buffer were tested: 1X PBS and 0.1X PBS. After obtaining data, it was concluded that MARCKS quenched the SUVs more than RND1. This could be due to the presence of more lysine amino acids in MARCKS, which …