Molecular Biology Commons^™

Measurement Of Elastic Modulus Of Collagen Type I Single Fiber, Pavel Dutov, Olga Antipova, Sameer Varma, Joseph P R O Orgel, Jay D Schieber

Molecular Biosciences Faculty Publications

Collagen fibers are the main components of the extra cellular matrix and the primary contributors to the mechanical properties of tissues. Here we report a novel approach to measure the longitudinal component of the elastic moduli of biological fibers under conditions close to those found in vivo and apply it to type I collagen from rat tail tendon. This approach combines optical tweezers, atomic force microscopy, and exploits Euler-Bernoulli elasticity theory for data analysis. This approach also avoids drying for measurements or visualization, since samples are freshly extracted. Importantly, strains are kept below 0.5%, which appear consistent with the linear …

Mir494 Reduces Renal Cancer Cell Survival Coinciding With Increased Lipid Droplets And Mitochondrial Changes, Punashi Dutta, Edward Haller, Arielle Sharp, Meera Nanjundan

Molecular Biosciences Faculty Publications

Background: miRNAs can regulate cellular survival in various cancer cell types. Recent evidence implicates the formation of lipid droplets as a hallmark event during apoptotic cell death response. It is presently unknown whether MIR494, located at 14q32 which is deleted in renal cancers, reduces cell survival in renal cancer cells and if this process is accompanied by changes in the number of lipid droplets.

Methods: 769-P renal carcinoma cells were utilized for this study. Control or MIR494 mimic was expressed in these cells following which cell viability (via crystal violet) and apoptotic cell numbers (via Annexin V/PI staining) were …

Direct Analysis In Real Time (Dart) Of An Organothiophosphate At Ultrahigh Resolution By Fourier Transform Ion Cyclotron Resonance Mass Spectrometry And Tandem Mass Spectrometry, Laszlo Prokai, Stanley M. Stevens Jr.

Molecular Biosciences Faculty Publications

Direct analysis in real time (DART) is a recently developed ambient ionization technique for mass spectrometry to enable rapid and sensitive analyses with little or no sample preparation. After swab-based field sampling, the organothiophosphate malathion was analyzed using DART-Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Mass resolution was documented to be over 800,000 in full-scan MS mode and over 1,000,000 for an MS/MS product ion produced by collision-induced dissociation of the protonated analyte. Mass measurement accuracy below 1 ppm was obtained for all DART-generated ions that belonged to the test compound in the …

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. …

Utility And Origin Of Blood-Based Autoantibodies For Early Detection And Diagnosis Of Neurodegenerative Diseases, Cassandra Demarshall

Graduate School of Biomedical Sciences Theses and Dissertations

Autoantibodies are self-reactive antibodies that have been widely implicated as causal agents of autoimmune diseases. They are found in the blood of all human sera, regardless of age, gender, or the presence or absence of disease. While the underlying reason for their ubiquity remains unknown, it has been hypothesized that they participate in the clearance of blood-borne cell and tissue debris generated in both healthy and diseased individuals on a daily basis. Although much evidence supports this debris clearance role, recent studies also suggest a causal role for autoantibodies in disease. My thesis work has focused on this "cause and/or …

Functional Analysis Of Rpl22: Coordinating Differentiation Signals And Developmental Gene Translation To Promote Cell Fate Decisions, Stephen Kim

Graduate School of Biomedical Sciences Theses and Dissertations

The execution of meiosis and spore formation in S. cerevisiae requires a transient transcription program that is initiated by Ime I-dependent destruction of the repressor Ume6. IMEJ transcription is tightly contro1led by both cell type and nutritional cues but how its translation is regulated has been unknown. This study demonstrates that Rpl22A and Rpl22B, eukaryotic-specific ribosomal protein paralogs of the 60S large subunit, are required for efficient Ime I translation. While IME1 mRNA is induced normally in the absence of both para logs following transfer to sporulation medium, Ume6 remains stabilized, downstream early meiotic gene remain repressed, and development is …

Low-Ω3 Fatty Acid And Soy Protein Attenuate Alcohol-Induced Fatty Liver And Injury By Regulating The Opposing Lipid Oxidation And Lipogenic Signaling Pathways., Karina Reyes-Gordillo, Ruchi Shah, Ravi Varatharajalu, Mamatha Garige, Leslie C. Leckey, M. Raj Lakshman

Biochemistry and Molecular Medicine Faculty Publications

Chronic ethanol-induced downregulation of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α) and upregulation of peroxisome proliferator-activated receptor gamma coactivator 1-beta (PGC1β) affect hepatic lipid oxidation and lipogenesis, respectively, leading to fatty liver injury. Low-ω3 fatty acid (Low-ω3FA) that primarily regulates PGC1α and soy protein (SP) that seems to have its major regulatory effect on PGC1β were evaluated for their protective effects against ethanol-induced hepatosteatosis in rats fed with Lieber-deCarli control or ethanol liquid diets with high or low ω3FA fish oil and soy protein. Low-ω3FA and SP opposed the actions of chronic ethanol by reducing serum and liver lipids with …

Transcriptomic Analysis Of Staphylococcal Srnas: Insights Into Species-Specific Adaption And The Evolution Of Pathogenesis, William H. Broach, Andy Weiss, Lindsey N. Shaw

Molecular Biosciences Faculty Publications

Next-generation sequencing technologies have dramatically increased the rate at which new genomes are sequenced. Accordingly, automated annotation programs have become adept at identifying and annotating protein coding regions, as well as common and conserved RNAs. Additionally, RNAseq techniques have advanced our ability to identify and annotate regulatory RNAs (sRNAs), which remain significantly understudied. Recently, our group catalogued and annotated all previously known and newly identified sRNAs in several Staphylococcus aureus strains. These complete annotation files now serve as tools to compare the sRNA content of S. aureus with other bacterial strains to investigate the conservation of their sRNomes. Accordingly, in …

Potential Role Of Pctaire-2, Pctaire-3 And P-Histone H4 In Amyloid Precursor Protein-Dependent Alzheimer Pathology, Dale Chaput, Lisa Kirouac, Stanley M. Stevens Jr., Jaya Padmanabhan

Molecular Biosciences Faculty Publications

Amyloid Precursor Protein (APP) is regulated in a mitosis-specific manner and plays a role in proliferative signaling in cells. Though APP-derived Aβ generation has a well-established role in neurodegeneration, the mechanistic role of APP in this process is not fully understood. Here, we performed an unbiased, comprehensive analysis of the phosphoproteome signature in APP-null neuroblastoma cells (B103) compared to those expressing APP-695 isoform (B103-695) to determine if APP expression affects protein phosphorylation. Stable isotope labeling by amino acids in cell culture (SILAC) followed by mass spectrometry-based phosphoproteomic analysis with PolyMAC identified a total of 2,478 phosphopeptides in the B103 and …

Antibodies Against A Secreted Product Of Staphylococcus Aureus Trigger Phagocytic Killing, Lena Thomer, Carla Emolo, Vilasack Thammavongsa, Hwan Keun Kim, Molly E. Mcadow, Wenqi Yu, Matthew Kieffer, Olaf Schneewind, Dominique Missiakas

Molecular Biosciences Faculty Publications

Host immunity against bacteria typically involves antibodies that recognize the microbial surface and promote phagocytic killing. Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of lethal bloodstream infection; however, vaccines and antibody therapeutics targeting staphylococcal surface molecules have thus far failed to achieve clinical efficacy. S. aureus secretes coagulase (Coa), which activates host prothrombin and generates fibrin fibrils that protect the pathogen against phagocytosis by immune cells. Because of negative selection, the coding sequence for the prothrombin-binding D1-D2 domain is highly variable and does not elicit cross-protective immune responses. The R domain, tandem repeats of a 27-residue peptide that bind …

Towards The Complete Small Rnome Of Acinetobacter Baumannii, Andy Weiss, William H. Broach, Mackenzie C. Lee, Lindsey N. Shaw

Molecular Biosciences Faculty Publications

In recent years, the Gram-negative bacterium Acinetobacter baumannii has garnered considerable attention for its unprecedented capacity to rapidly develop resistance to antibacterial therapeutics. This is coupled with the seemingly epidemic emergence of new hyper-virulent strains. Although strain-specific differences for A. baumannii isolates have been well described, these studies have primarily focused on proteinaceous factors. At present, only limited publications have investigated the presence and role of small regulatory RNA (sRNA) transcripts. Herein, we perform such an analysis, describing the RNA-seq-based identification of 78 A. baumannii sRNAs in the AB5075 background. Together with six previously identified elements, we include each of …

Peptidoglycan Recycling In Gram-Positive Bacteria Is Crucial For Survival In Stationary Phase, Marina Borisova, Rosmarie Gaupp, Amanda Duckworth, Alexander Schneider, Désirée Dalügge, Maraike Mühleck, Denise Deubel, Sandra Unsleber, Wenqi Yu, Günther Muth, Markus Bischoff, Friedrich Götz, Christoph Mayer

Molecular Biosciences Faculty Publications

Peptidoglycan recycling is a metabolic process by which Gram-negative bacteria reutilize up to half of their cell wall within one generation during vegetative growth. Whether peptidoglycan recycling also occurs in Gram-positive bacteria has so far remained unclear. We show here that three Gram-positive model organisms, Staphylococcus aureus, Bacillus subtilis, and Streptomyces coelicolor, all recycle the sugar N-acetylmuramic acid (MurNAc) of their peptidoglycan during growth in rich medium. They possess MurNAc-6-phosphate (MurNAc-6P) etherase (MurQ in E. coli) enzymes, which are responsible for the intracellular conversion of MurNAc-6P to N-acetylglucosamine-6-phosphate and d-lactate. By applying mass spectrometry, we observed accumulation of MurNAc-6P in …

Comparative Proteomic Analysis Of Extracellular Vesicles From Prostate Cancer-Derived Cell Lines, Gloria Polanco

Open Access Theses & Dissertations

Prostate cancer (PCa) is the leading non-cutaneous malignancy and the second deadliest among American men. PCa mortality rates among African American men are much higher than any other ethnic group, and the same is true for men of African ancestry world-wide. There is also a lack of reliable diagnostic markers and effective treatment options. Extracellular vesicles (EVs) have been observed to play an important role in cancer processes such as promotion of tumor growth and metastasis. They are also a promising source of diagnostic markers. This study addresses these problems by studying the proteome of EVs derived from PCa cells …

Defining And Characterizing The Step In The Hiv-1 Viral Life Cycle Affected By Fullerene Derivatives, Zachary Sean Martinez

Open Access Theses & Dissertations

Fullerene derivatives, both C60 and C70, were synthesized and characterized to test their activity against HIV-1 infection. The derivatives tested have previously been reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase. It was found that viruses produced in the presence of low micromolar concentrations of most of these fullerene derivatives exhibit a reduction in viral infectivity greater than 99%. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. These compounds did not affect infectivity of mature virions, indicating no effect on the early steps of the …

Elucidating The Molecular Mechanism Of Action By Which Rs1-208b Induces Apoptosis In Hematological Cancers, Ruben Israel Calderon

Open Access Theses & Dissertations

The 26S proteasome has been successfully targeted to treat multiple myeloma. However, the effect can sometimes be reversed as cells acquire resistance to chemotherapy. Recently, combining proteasome inhibitors with indirect proteasome inhibitors has been proposed in order to delay and even reverse resistance. Small molecules derived from 4-piperidinone that maintain an unsaturated β-carbonyl group are thought to interact with the thiol group of catalytically active cysteine residues in deubiquitinases that associate with the 26S proteasome, effectively inhibiting the proteasome.

RS1-208b was selected following a high-throughput screening of a small library of 4-piperidinone derived curcumin structural analogs due to its selectivity …

Preventing Thymus Involution In K5.Cyclin D1 Transgenic Mice Sustains The Naïve T Cell Compartment With Age, Michelle L. Bolner

Dissertations and Theses (Open Access)

The thymus maintains T cell receptor (TCR) repertoire diversity through perpetual release of self-MHC restricted naive T cells. However, thymus involution during the aging process reduces naïve T cell output, leading to defective immune responsiveness to newly encountered antigens. We have found that early thymus involution precipitates the age-associated shift favoring memory T cell dominancy in young control mice. Furthermore, we have shown that age-related thymus involution is prevented in mice expressing a keratin 5 promoter-driven Cyclin D1 (K5.D1) transgene in thymic epithelial cells (TECs). Thymopoiesis occurs normally in K5.D1 transgenic thymi and sustains T cell output to prevent the …

Molecular Regulation Of Vascular Calcification In Murine Models Of Atherosclerosis, Shanshan Gao

Dissertations and Theses (Open Access)

Background: Calcification occurs often in the atherosclerotic lesions of patients with coronary heart disease and animals with hypercholesterolemia, such as apolipoprotein-E deficient (ApoE-/-) mice. However, the mechanism(s) underlying the development of calcification in atherosclerosis remains unclear. ApoE acts as a lipid transporter, but also has been recognized as a potential regulator of osteogenesis. Little information is available as to whether ApoE has any direct impact on osteogenesis and calcification in vascular smooth muscle cells (VSMC). Several signal transduction pathways play a role in regulation of calcification, including the Wnt/β-catenin system and potentially GTAP, an ubiquitin-conjugating enzyme responsible for protein …

Leptin Regulates The Expression Of Autophagy-Related Genes In Chickens, Peter Olawale Ishola

Graduate Theses and Dissertations

Autophagy or cellular self-digestion, a lysosomal degradation pathway that is conserved from yeast to human, plays a key role in recycling cellular constituents, including damaged organelles. It also plays a pivotal role in the adaptation of cells to a plethora of distinct stressors including starvation. Autophagy has been extensively studied in mammals and yeast, but little is known in avian species. Thus, the major objective of the present study was to determine the effects of leptin on autophagy-related genes in chicken hypothalamus, muscle and liver. Leptin is an adipocytokine that is mostly produced by white adipose cells in mammals (as …

Transcriptomics Of Chicken Primordial Germ Cells, Nhung Thi Nguyen

Graduate Theses and Dissertations

Chicken primordial germ cells (PGCs) are derived from extraembryonic tissue of the embryo and first appear at stage X of development. They enter the bloodstream and migrate to the genital ridge, unite with somatic tissue to form a developing gonad, and then differentiate to sperm or ova (Fujimoto et al., 1976). Understanding molecular features of both male and female PGCs not only clarify the differentiation mechanism of such cells toward different germ lines, but will also help in selecting for highly productive types of commercial chicken. Most previous studies focused on the location of PGCs (Eyal-Giladi et al., 1981; Swift …

Hepatic Nutrient And Hormonal Regulation Of The Pancreatic-Derived Factor (Pander) Promoter, Whitney Ratliff

USF Tampa Graduate Theses and Dissertations

PANcreatic-DERived factor (PANDER, FAM3B) has been shown to regulate glycemic levels via interactions with both pancreatic islets and the liver. Although PANDER is predominantly expressed from the endocrine pancreas, recent work has provided sufficient evidence that the liver may also be an additional tissue source of PANDER production. At physiological levels, PANDER is capable of disrupting insulin signaling and promoting increased hepatic glucose production. As shown in some animal models, strong expression of PANDER, induced by viral delivery within the liver, induces hepatic steatosis. However, no studies to date have explicitly characterized the transcriptional regulation of PANDER from the liver. …

The Generation, Exploitation And Future Of Induced Pluripotent Stem Cells, Jacob Steenwyk

Scholarly Undergraduate Research Journal at Clark (SURJ)

The foundational advancements of John Gurdon and Shinya Yamanaka have improved understanding of dedifferen- tiation of cells to a pluripotent state. The seminal discovery established a novel system to study disease pathogenesis, drug screening, and toxicity, as well as sprouted the new field of regenerative medicine. In this article, the method- ology to obtain dedifferentiated cells, known as induced pluripotent stem (iPS) cells, subsequent validation, and application of which are reviewed. The experiments investigated here aim to demonstrate the capacity of iPS cells to replace the ethically-gray human embryonic cells by developing human livers and viable, healthy animals. It is …

Characterization And Diurnal Measurement Of Oral Inflammation In Association With Glycemic Control, Periodontal Status, & Glucose Stimulation, Melanie N. Kuehl

USF Tampa Graduate Theses and Dissertations

Diabetes has afflicted 8.3%, approximately 25.8 million, of the United States population and is the seventh leading cause of death [1]. Type I diabetes (T1D) accounts for 5 to 10% of all diagnosed cases of diabetes in the United States [2]. If present trends continue, the rate of T1D incidence among children under the age of 14 will increase by 3% globally [3]. T1D is an autoimmune disorder in which the β-cells of the pancreatic islets are destroyed, leading to high blood sugar. Hyperglycemia and loss of immunological tolerance to self-antigens are common associations of T1D [4]. Periodontal disease impacts …

Reactive Oxygen Species-Mediated Neurodegeneration Is Independent Of The Ryanodine Receptor In Caenorhabditis Elegans, Lyndsay E.A. Young, Daniel C. Williams

Journal of the South Carolina Academy of Science

Despite the significant impacts on human health caused by neurodegeneration, our understanding of the degeneration process is incomplete. The nematode Caenorhabditis elegans is emerging as a genetic model organism well suited for identification of conserved cellular mechanisms and molecular pathways of neurodegeneration. Studies in the worm have identified factors that contribute to neurodegeneration, including excitotoxicity and stress due to reactive oxygen species (ROS). Disruption of the gene unc-68, which encodes the ryanodine receptor, abolishes excitotoxic cell death, indicating a role for calcium (Ca²⁺) signaling in neurodegeneration. We tested the requirement for unc-68 in ROS-mediated neurodegeneration using the …

Dna Repair Deficiency In Huntington's Disease Fibroblasts And Induced Pluripotent Stem Cells, Peter Anthony Mollica

Biological Sciences Theses & Dissertations

Mutant huntingtin protein (mhtt)– the protein responsible for cellular dysfunction in Huntington’s disease (HD) –is a product of an expanded trinucleotide repeat (TNR) cytosine-adenine-guanine (CAG) sequence in exon 1 of the huntingtin (HTT) gene. The pathology of HD has been extensively researched; however, the mechanism by which the disease-causing TNR expansions occur in somatic cells remains elusive. Interestingly, HD has often been referred to a ‘DNA repair disease’, even though DNA repair dysfunction in situ has not been identified. We hypothesized that presence of the mhtt protein affects the expression of DNA repair genes used to address DNA repair, ultimately …

Biophysical Properties Of Cellular Membranes In Gram-Positive Bacterial Pathogens And Their Impact On Major Physiological Attributes And Virulence Determinants, Suranjana Sen

Theses and Dissertations

The cytoplasmic membrane of bacterial cells, forming an essential barrier from the surroundings, is a critical component of cellular physiology ensuring proper survival and maintenance of major cellular functions. The integrity of the membrane is an important feature that plays an essential role in the transport of solutes and nutrients through active and passive pathways, functions of membrane-associated proteins, electron transport and ATP synthesis, maintaining turgor pressure and combating environmental stresses, and thus is a crucial factor of a majority of cellular adaptations. The various biophysical properties affecting the integrity of this membrane are mainly determined by the composition and …

Function Of Long Noncoding Rnas In Breast Cancer, Edward J. Richards

USF Tampa Graduate Theses and Dissertations

Breast cancer is a disease that will be diagnosed in about 1 in 10 women throughout their lifetime. The majority of breast cancers are originated from the epithelial cells of the mammary ducts, and this occurrence can be due to several factors including hereditary and acquired mutation. There are several major breast cancer subtypes, including estrogen receptor-α (ERα)-positive, HER2-enriched and triple-negative (TNBC). Patients diagnosed with ER+ tumors are generally treated with estrogen blockers (e.g., tamoxifen, letrozole and fulvestrant). Patients with HER2+ tumors are commonly administered with drugs that block HER2 signaling (e.g., trastuzumab) or inhibit HER2’s tyrosine kinase activity (e.g., …

Direct Regulation Of Apoptosis By Linear Ubiqutin Chain Assembly Complex (Lubac) And Feedback Regulation Of Lubac Function By Caspases, Donghyun Joo

Dissertations and Theses (Open Access)

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine that plays a role in various cellular processes such as proliferation, differentiation (mainly through NF-κB signaling) and death (via apoptosis signaling). Recently, linear ubiquitination by LUBAC (linear ubiquitin chain assembly complex) was reported to have a regulatory function in TNF-α mediated NF-κB activation. Although LUBAC is suggested to control not only NF-kB signaling but also the apoptosis pathway, the precise mechanism of apoptosis regulation remains unknown. Moreover, NF-κB and apoptosis pathways have opposed but fundamental functions for various cellular processes. Although these two pathways actively interplay to balance the death and survival, the …

Histone H3 K4 Methylation Regulates The Spindle Assembly Checkpoint Through Direct Binding Of Multiple Checkpoint Components And Cdc20, Andria C. Schibler

Dissertations and Theses (Open Access)

Histone H3K4 methylation is conserved across species and is associated with active transcription. By using Saccharomyces cerevisiae, we found histone H3K4 methylation has a previously unknown role in regulating mitosis through the Spindle Assembly Checkpoint. The Spindle Assembly Checkpoint ensures duplicated chromosomes are segregated correctly and each daughter cell receives one full copy of the genome. Our data show SET1 mutants and histone H3K4 mutants display a resistance to the mitotic poison, benomyl. Moreover methylated histone H3 directly binds to Spindle Assembly Checkpoint proteins Bub3 and Mad2 as well as the activator of the Anaphase Promoting Complex (APC) protein …

Comparison Of Different Modulators That Affect Macrophage Activation In Vitro, Alda Alexa Díaz Pérez

Graduate Theses and Dissertations

Inflammation is known as a mechanism to regulate and control infections as well as promote tissue repair. Macrophages (Mф) are known to be a major cell type in the initiation, sustainability and resolution of inflammation. Moreover, Mф are essential for the remodeling process that is also known as the wound healing response. The objective of this research was to compare five modulators (acetylsalicylic acid (ASA), dexamethasone (DEX), prostaglandin E2 (PGE2), iloprost, and resolvin D1 (RvD1) for their anti-inflammatory effects on macrophages in vitro. Then, Mф phenotype in terms of gene expression and secreted cytokine response was determined. Our study compared …

Cell Wall Mutants In Arabidopsis Thaliana, Christy Jane Moore

Theses and Dissertations

Plant cell walls are versatile structures, playing important roles in communication, defense, organization and support. The importance of each of these functions varies by cell type, with specialized cells often utilizing one or two functions more than others. Trichomes, or leaf hairs, and hypocotyl cells for instance, exhibit distinct cell wall characteristics. Trichomes have developed very thick cell walls with several raised structures, known as papillae, on their surfaces. It is believed that these cells function in defense against predators, making it difficult to crawl on the leaf surface, and in protection against ultra violet radiation, through refraction of light …