Cell Biology Commons^™

The Effect Of High Terperature On Mating: Developmental Buffering Of S. Cerevisiae To The Environment, Sarah Hosie

Renée Crown University Honors Thesis Projects - All

In Saccharomyces cerevisiae, cellular polarization is an essential structural and functional aspect of growth and development. It is responsible for yielding and maintaining cellular asymmetry, and allows for cells to function. Mating in S. cerevisiae is a process that incorporates cell-to-cell signaling, signal transduction, cellular polarization, plasmogamy, karyogamy, and many other cellular processes. Each of these steps is mediated by a myriad of signaling proteins that are involved in a signaling cascade that is regulated by both extracellular and intracellular signals. Much is known about the mating process and pathway in S. cerevisiae. However, this project aimed to …

Overexpression And Gene Profiling Of Asparagine Synthetase In Hybrid Poplar, Kristopher Murray

Renée Crown University Honors Thesis Projects - All

Plants with polysaccharide-rich secondary cell walls have great potential as a source of carbohydrates for bioethanol production. However, the presence of phenolic lignin inhibits the isolation of bioethanol precursors cellulose and hemicellulose from the secondary cell wall. Recent studies have linked nitrogen availability to secondary cell wall development and composition, making nitrogen metabolism genes an interesting target in the improvement of plant cell walls for biofuels production. Plants use a nitrogen assimilation pathway to convert inorganic nitrogen sources into organic sources, included amino acids, which play key roles in metabolism and cell wall development. Asparagine synthetase (AS), a key enzyme …

Characterization Of Ghrelin O-Acyltransferase Active Site, Leslie Patton

Renée Crown University Honors Thesis Projects - All

Ghrelin, first discovered in 1999, is a 28-amino acid peptide hormone involved in the regulation of appetite, insulin secretion and sensitivity, and many neurological effects such as learning, memory, and depression.^1-6 Ghrelin has been identified to have a unique posttranslational octanoylation carried out by the enzyme ghrelin O-acyltransferase (GOAT). This distinctive modification is a point of interest in studying GOAT whereby blocking the acylation of the ghrelin could potentially halt the activity of the peptide hormone and provide a means of treating obesity, diabetes, and other diseases affected by ghrelin levels. The duration of my project involved working …

The Development Of Skeletal Muscle In Young Horses: An Ultrasonography And Satellite Cell Approach, Emma K. Lavigne

Honors Scholar Theses

Muscle growth in young horses is characterized by an increase in muscle cross-sectional area, which can be accomplished through the activation and differentiation of satellite cells. Satellite cells can be stimulated or inhibited in response to different cytokines and growth factors and are key mediators of muscle hypertrophy and regeneration. The aim of this study was to investigate the growth of the longissimus dorsi (LD) muscle in horses under 5 years of age and to obtain preliminary data on satellite cell behavior in foals. The area, width, height, and subcutaneous fat were measured using ultrasonography at 6-month increments over the …

Activation Of Nf-Κb Transcription Factor During In Vitro Differentiation Of Mouse Embryonic Stem Cells, Natalya A. Ortolano

Honors Theses

Embryonic stem cells (ESCs) are a promising cell source for regenerative medicine. However, recent studies indicated that ESCs and ESC-derived cells (ESC-DCs) lack functional innate immunity against various pathogens and inflammatory cytokines. This presents a barrier to clinical application, as ESC-DCs would be placed in a wound site and exposed to pathogens and inflammatory cytokines. Using mouse ESCs (mESCs) as a model, we recently demonstrated that they are deficient in expressing type I interferons (IFN) and inflammatory cytokines. To determine the molecular basis for this finding, this study examined the activation state of nuclear factor-κB (NF-κB), a transcription factor that …

The Hippo Pathway Effector Yki Downregulates Wg Signaling To Promote Retinal Differentiation In The Drosophila Eye, Erika Lynn Wittkorn, Ankita Sarkar, Kristine Garcia, Madhuri Kango-Singh, Amit Singh

Biology Faculty Publications

The evolutionarily conserved Hippo signaling pathway is known to regulate cell proliferation and maintain tissue homeostasis during development. We found that activation of Yorkie (Yki), the effector of the Hippo signaling pathway, causes separable effects on growth and differentiation of theDrosophila eye. We present evidence supporting a role for Yki in suppressing eye fate by downregulation of the core retinal determination genes. Other upstream regulators of the Hippo pathway mediate this effect of Yki on retinal differentiation. Here, we show that, in the developing eye, Yki can prevent retinal differentiation by blocking morphogenetic furrow (MF) progression and R8 specification. …

Igfbp2 Potentiates Egfr-Stat3 Signaling In Glioma, Yingxuan Chua

Dissertations and Theses (Open Access)

Gliomas are clinically challenging brain tumors with dismal survival rates due to its infiltrative nature and ineffective standard therapy. Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the contributions of intracellular IGFBP2 to tumor development and progression are poorly understood. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of EGFR, which subsequently activates STAT3 signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via …

Src Homology 2 Domain-Containing 5’-Inositol Phosphatase-2 (Ship2) Is An Effector Of Lymphatic Dysfunction, Germaine D. Agollah

Dissertations and Theses (Open Access)

The lymphatic system is essential for the transport of excess fluid, protein, and foreign materials from interstitial tissues to lymph nodes; for immune surveillance, and to maintain fluid homeostasis. Dysregulated lymphatics can be attributed to pathological conditions including tumor metastasis, inflammation, chronic wounds, obesity, blood vascular disorders, and lymphedema. Of these, lymphedema is the most extreme of lymphatic disorders and is represented by a spectrum of symptoms ranging from mild, subtle presentation to severe, disfiguring, overt presentation. Lymphedema is more manageable in the early stages of disease but severely reduces quality of life with progression. Due to lack of molecular …

Dna Polymerase Θ (Polq) And The Cellular Defense Against Dna Damage, Matthew J. Yousefzadeh

Dissertations and Theses (Open Access)

In mammalian cells, DNA polymerase θ (POLQ) is an unusual specialized DNA polymerase whose in vivo function is under active investigation. The protein is comprised of an N-terminal helicase-like domain, a C-terminal DNA polymerase domain, and a large central domain that spans between the two. This arrangement is also found in the Drosophila Mus308 protein, which helps confer resistance to DNA interstrand crosslinking agents. Homologs of POLQ and Mus308 are found in eukaryotes, including plants, but a comparison of phenotypes suggests that not all of these genes are functional orthologs. Flies with defective Mus308 are sensitive to DNA interstrand crosslinking …

Understanding The Role Of Sumoylation In Regulating Lkb1 Function, Joan W. Ritho

Dissertations and Theses (Open Access)

Energy homeostasis in a cell is critical for its survival during metabolic stress. Liver kinase B1 (LKB1), one of the key regulators of cellular energy balance, was initially discovered as a tumor suppressor mutated in patients with Peutz-Jeghers syndrome. Germline mutations in LKB1 predispose patients to develop several benign and malignant tumors including gastrointestinal and lung cancers. In 2003, several groups demonstrated that LKB1is a major upstream kinase of the energy sensor AMP-activated protein kinase (AMPK), directly associating it with the regulation of energy balance in cells. During energy stress, LKB1 phosphorylates AMPK at threonine 172 (T172) resulting in AMPK …

Regulation Of Cell Adhesion By The Ferm Proteins, Ptpn14 And Merlin, Patty Dimarco Hewitt

Dissertations and Theses (Open Access)

Cell-cell adhesion is critical for the control of tissue organization and homeostasis. A family of proteins that regulate cell-cell adhesions is the FERM (4.1 protein, Ezrin, Radixin, Moesin) domain-containing proteins.One FERM domain protein, the non-receptor tyrosine phosphatase PTPN14, is mutated or deleted in several human cancers suggesting that it may be involved in tumor development and/or progression. Additionally, the loss of the FERM domain protein Merlin is associated with tumor development and metastasis.Both PTPN14 and Merlin have been shown to localize and possibly regulate adherens junction (AJ) functions. This work sought to determine if …

Inducing And Characterizing M2c Macrophages At A Non-Degradable Implant In Vivo, Geoffrey David Keeler

Graduate Theses and Dissertations

The implantation of biomaterials in the body leads to a reaction known as the foreign body response (FBR) which leads to the eventual encapsulation of the biomaterial. This encapsulation proves to be detrimental to certain biomaterials, such as implanted glucose sensors, which rely on interacting with the extracellular space for proper function. Altering the FBR has become of interest in an effort to increase the longevity and integration of biomaterials. One strategy for altering the FBR is by targeting the macrophage, shown to play an important role in the FBR. In this work, the microdialysis sampling technique was used to …

Activating The Msh2/Msh6 Apoptotic Pathway In Cancer Cells Using Non-Reserpine Compounds, Jacob M. Mauceri

Honors College Theses

DNA mismatch repair (MMR) is a system that is highly conserved in both prokaryotes and eukaryotes. The heterodimeric protein MutSα and a suite of associated proteins are essential in the recognition and repair of DNA afflicted with mispaired bases and short insertion/deletion loops, but are also implicated in funneling damaged cells towards apoptosis via a key conformational change in a subunit of the MutSα complex. This conformation can be bound specifically by the small molecule reserpine. Molecular dynamics modeling and virtual screening were used to identify additional small molecule novel ligands with the predicted ability to selectively bind this “death” …

Local Modulation And Measurement Of Macrophage-Derived Bioactive Proteins From Implanted Biomaterials In Rat, Geetika Bajpai

Graduate Theses and Dissertations

Fibrosis around the implanted medical devices is a severe problem that can plague long-term device reliability. Activation of macrophage phenotype (macrophage polarization) has emerged as a new and possible means for reducing fibrosis in the fields of biomaterials and regenerative medicine. Macrophages are phagocytic cells that respond to microenvironmental cues that direct their phenotype. Macrophage activation has been widely studied in mouse and human in the context of tumor biology, yet little information is available regarding how macrophage activation could be used in a biomaterials context. Further, rats rather than mice are the common subjects in biomaterials experiments. A significant …

Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic

Master's Theses

Stem cell niches are highly organized and specialized microenvironments located within specific tissues of both vertebrate and invertebrate organisms [1]. In Drosophila melanogaster, three distinct stem cell niches have been identified within the ovary including the germline stem cell (GSC), follicle stem cell (FSC), and escort stem cell (ESC) niche. Recently, Fregoso-Lomas et al. [2] reported that Gurken/Epidermal Growth Factor Receptor (EGFR) signaling is modulated within posterior ovarian follicle cells by Midline (Mid). The mid gene encodes a T-box transcription factor protein that specifies cell fates in the developing heart [3][4], central nervous system [5][6], epidermis [7], and eye …

Impacts Of Micrornas On Skeletal Muscle Protein Synthesis And Mitochondrial Quality, David Lee

Graduate Theses and Dissertations

microRNA (miRNA) post-transcriptional modification is becoming a well-established mechanism for controlling mRNA translation. microRNAs -1, -133, and -206 are under the control of skeletal muscle promoters and affect muscle plasticity and metabolic health. A detailed review on the generation and processing of miRNAs with a view to skeletal muscle brings up intriguing connections in the transcriptional connections between multiple miRNAs. Additionally, exciting new research has defined a role of miRNAs in skeletal muscle mitochondria showing an additional, direct link to metabolic function. Multiple investigations in models of exercise, aging, hypertrophy, and injury have shown how these interventions can affect miRNA …

Live Imaging Of The Ependymal Cilia In The Lateral Ventricles Of The Mouse Brain, Alzahra J. Al Omran, Hannah C. Saternos, Tongyu Liu, Surya M. Nauli, Wissam A. Aboualaiwi

Pharmacy Faculty Articles and Research

Multiciliated ependymal cells line the ventricles in the adult brain. Abnormal function or structure of ependymal cilia is associated with various neurological deficits. The current ex vivo live imaging of motile ependymal cilia technique allows for a detailed study of ciliary dynamics following several steps. These steps include: mice euthanasia with carbon dioxide according to protocols of The University of Toledo’s Institutional Animal Care and Use Committee (IACUC); craniectomy followed by brain removal and sagittal brain dissection with a vibratome or sharp blade to obtain very thin sections through the brain lateral ventricles, where the ependymal cilia can be visualized. …

Analysis Of Chd Remodelers During Development: A Tale In Two Organisms, Brett Bishop

Open Access Dissertations

The correct development of different organisms requires the precise timing of genes important for development transitions. Organisms have recruited ATP-dependent chromatin remodelers to ensure the correct timing of gene expression during developmental transitions. Here I show how different CHD ATP-dependent chromatin remodelers regulate developmental transitions of different organisms. I show that PICKLE not only promotes H3K27me3 during development to repress developmental genes but also is targeted to these genes. The association of PICKLE to these genes suggests that both repression and H3K27me3 levels is a direct action of PICKLE on these loci. Using zebrafish as a model system, I show …

The Effects Of Propofol, Sodium Pentobarbital, And Ketamine Hydrochloride On In Vitro Mouse Embryonic Development, Tyler C. Balak

Theses and Dissertations in Biomedical Sciences

Every year more than 75,000 pregnant women are exposed to teratogenic medications or general anesthesia during non-obstetric surgery in the US,1-4 and embryonic effects of general anesthesia are of particular interest in laboratory research and veterinary medicine. The mouse system is used to screen potential toxic effects of anesthetics used in egg retrieval for in vitro fertilization (IVF), or those of pharmacologic agents which may come in contact with the egg or early embryo. Mouse preimplantation 2-cell embryos were exposed in vitro to incremental concentrations of common general anesthetics within and exceeding the normal clinical dosage range for mice (propofol …

The Evolutionary Origination And Diversification Of A Dimorphic Gene Regulatory Network Through Parallel Innovations In Cis And Trans, Eric M. Camino, John C. Butts, Alison J. Ordway, Jordan E. Vellky, Mark Rebeiz, Thomas M. Williams

Biology Faculty Publications

The origination and diversification of morphological characteristics represents a key problem in understanding the evolution of development. Morphological traits result from gene regulatory networks (GRNs) that form a web of transcription factors, which regulate multiple cis-regulatory element (CRE) sequences to control the coordinated expression of differentiation genes. The formation and modification of GRNs must ultimately be understood at the level of individual regulatory linkages (i.e., transcription factor binding sites within CREs) that constitute the network. Here, we investigate how elements within a network originated and diversified to generate a broad range of abdominal pigmentation phenotypes among Sophophora fruit flies. …

Cell Type-Specific Responses To Wingless, Hedgehog And Decapentaplegic Are Essential For Patterning Early Eye-Antenna Disc In Drosophila, Jong-Hoon Won, Orkhon Tsogtbartarr, Wonseok Son, Amit Singh, Kwang-Wook Choi, Kyung-Ok Cho

Biology Faculty Publications

The Drosophila eye-antenna imaginal disc (ead) is a flattened sac of two-layered epithelia, from which most head structures are derived. Secreted morphogens like Wingless (Wg), Hedgehog (Hh), and Decapentaplegic (Dpp) are important for early patterning of ead, but the underlying mechanisms are still largely unknown. To understand how these morphogens function in the ead of early larval stages, we used wg-LacZ and dpp-Gal4 markers for the examination of wild-type and mutant eads. We found that the ead immediately after hatching was crescent-shaped with the Bolwig’s nerve at the ventral edge, suggesting that it consists of dorsal domain. In a subsequent …

Targets Identification And Characterization Of Tramp Comples In Mouse, Fengchao Wang

Master's Theses (2009 -)

RNA surveillance and degradation play an important role in the development and growth of organisms by eliminating RNA that contains errors, or that is no longer needed by the cell. In some processes, RNAs designated to be degraded are first labeled and then specifically recognized by the exosome, which performs the final degradation. One of the key labeling factors in yeast is the TRAMP complex, a three-subunit complex composed of Air2, Trf4 and Mtr4. Air2 facilitates TRAMP binding of RNA, Trf4 appends a 3′ end polyA tail and Mtr4 regulates the rate of adenylation and modifies RNA structures for ease …

Effects Of Cannabidiol On Contractions And Calcium Signaling In Rat Ventricular Myocytes, Ramez M. Ali, Lina T. Al Kury, Keun-Hang Susan Yang, Anwar Qureshi, Mohanraj Rajesh, Sehamuddin Galadari, Yaroslav M. Shuba, Frank Christopher Howarth, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Cannabidiol (CBD), a major nonpsychotropic cannabinoid found in Cannabis plant, has been shown to influence cardiovascular functions under various physiological and pathological conditions. In the present study, the effects of CBD on contractility and electrophysiological properties of rat ventricular myocytes were investigated. Video edge detection was used to measure myocyte shortening. Intracellular Ca2+ was measured in cells loaded with the Ca2+ sensitive fluorescent indicator fura-2 AM. Whole-cell patch clamp was used to measure action potential and Ca2+ currents. Radioligand binding was employed to study pharmacological characteristics of CBD binding. CBD (1 μM) caused a significant decrease in the amplitudes of …

Plasma Activated Air Mediates Gene Transfer, Chelsea M. Edelblute

Biological Sciences Theses & Dissertations

Cold plasma is produced when strong applied electric fields accelerate free electrons, which dissociate, excite, or ionize gaseous molecules [1]. The deposition of ions from the plasma source is dependent on power generation, input gas composition, and gas flow rate. In the presence of reactive species, the membrane of eukaryotic cells is compromised allowing for otherwise impermeant molecules, such as DNA, to enter the inner-cell milieu [2].

The efficacy of a novel cold plasma reactor based on shielded sliding discharge for the delivery of plasmid DNA was assessed. The device is entirely non-contact, wherein the plasma never directly touches the …

Violacein Induces P44/42 Mitogen-Activated Protein Kinase‑Mediated Solid Tumor Cell Death And Inhibits Tumor Cell Migration, Toral Mehta, Koen Vercruysse, Terrance Johnson, Anthony Okechukwu Ejiofor, Elbert Myles, Quincy Antoine Quick

Biology Faculty Research

Microbial secondary metabolites have emerged as alternative novel drugs for the treatment of human cancers. Violacein, a purple pigment produced by Chromobacterium violaceum, was investigated in the present study for its anti‑tumor properties in tumor cell lines. Clinically applicable concentrations of violacein were demonstrated to inhibit the proliferative capacity of tumor cell lines according to a crystal violet proliferation assay. The underlying mechanism was the promotion of apoptotic cell death, as indicated by poly(ADP ribose) polymerase cleavage and p44/42 mitogen‑activated protein kinase signaling determined by western blot analysis. Collectively, this provided mechanistic evidence that violacein elicits extracellular-signal regulated kinase‑induced apoptosis …

Analysis Of The Candida Albicans Phosphoproteome, S. D. Willger, Z. Liu, R. A. Olarte, M. E. Adamo, J E. Stajich, L C. Myers, A N. Kettenbach, D A. Hogan

Dartmouth Scholarship

Candida albicans is an important human fungal pathogen in both immunocompetent and immunocompromised individuals. C. albicans regulation has been studied in many contexts, including morphological transitions, mating competence, biofilm forma- tion, stress resistance, and cell wall synthesis. Analysis of kinase- and phosphatase-deficient mutants has made it clear that pro- tein phosphorylation plays an important role in the regulation of these pathways. In this study, to further our understanding of phosphorylation in C. albicans regulation, we performed a deep analysis of the phosphoproteome in C. albicans. We identified 19,590 unique peptides that corresponded to 15,906 unique phosphosites on 2,896 proteins. The …

Promoting Genome Stability Via Multiple Dna Repair Pathways, Scott Cukras

USF Tampa Graduate Theses and Dissertations

Maintaining genome integrity is indispensible for cells to prevent and limit accruement of deleterious mutations and to promote viable cell growth and proliferation. Cells possess a myriad of mechanisms to detect, prevent and repair incurred cellular damage. Here we discuss various proteins and their accompanying cellular pathways that promote genome stability. We first investigate the NEDD8 protein and its role in promoting homologous recombination repair via multiple Cullin E3 ubiquitin ligases. We provide specific mechanisms through which, UBE2M, an E2 conjugating enzyme, neddylates various Cullin ligases to render them catalytically active to degrade their substrates by the proteasome. We show …

Use And Misuse Of Material Transfer Agreements: Lessons In Proportionality From Research, Repositories, And Litigation, Tania M. Bubela, Jenilee Guebert, Amrita Mishra

Office of the Provost

Material transfer agreements exist to facilitate the exchange of materials and associated data between researchers as well as to protect the interests of the researchers and their institutions. But this dual mandate can be a source of frustration for researchers, creating administrative burdens and slowing down collaborations. We argue here that in most cases in pre-competitive research, a simple agreement would suffice; the more complex agreements and mechanisms for their negotiation should be reserved for cases where the risks posed to the institution and the potential commercial value of the research reagents is high.

Trehalose Is A Chemical Attractant In The Establishment Of Coral Symbiosis, M. Hagedorn, V. Carter, N. Zuchowicz, M. Phillips, C. Penfield, B. Shamenek, Elizabeth A. Vallen, F. W. Kleinhans, K. Peterson, M. White, P. H. Yancey

Biology Faculty Works

Coral reefs have evolved with a crucial symbiosis between photosynthetic dinoflagellates (genus Symbiodinium) and their cnidarian hosts (Scleractinians). Most coral larvae take up Symbiodinium from their environment; however, the earliest steps in this process have been elusive. Here we demonstrate that the disaccharide trehalose may be an important signal from the symbiont to potential larval hosts. Symbiodinium freshly isolated from Fungia scutaria corals constantly released trehalose (but not sucrose, maltose or glucose) into seawater, and released glycerol only in the presence of coral tissue. Spawning Fungia adults increased symbiont number in their immediate area by excreting pellets of Symbiodinium, and …

The Effects Of Actomyosin Disruptors On The Mechanical Integrity Of The Avian Crystalline Lens, Gah-Jone Won, Douglas S. Fudge, Vivian Choh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Purpose: Actin and myosin within the crystalline lens maintain the structural integrity of lens fiber cells and form a hexagonal lattice cradling the posterior surface of the lens. The actomyosin network was pharmacologically disrupted to examine the effects on lenticular biomechanics and optical quality. Methods: One lens of 7-day-old White Leghorn chickens was treated with 10 μM of a disruptor and the other with 0.01% dimethyl sulfoxide (vehicle). Actin, myosin, and myosin light chain kinase (MLCK) disruptors were used. The stiffness and the optical quality of the control and treated lenses were measured. Western blotting and confocal imaging …