Cell Biology Commons^™

Chemical Induced Hypoxia Differentially Affects Gene Expression In Human Neuronal Cells, Natasha V. Pavlichko

Seton Hall University Dissertations and Theses (ETDs)

Previously, our laboratory used desferoxamine (DFO), to generate hypoxic conditions (a low oxygen condition) which decreased human neuronal cell viability, but some cells still survived. These surviving neurons showed no morphological changes when compared to the non-treated group. However, the alteration of several intracellular events were detected, such as an increase of hypoxia inducible factor 1 (HIF-1) mRNA levels, a decrease of human mu opioid receptor (hMOR) message, and no change of human delta opioid receptor (hDOR) receptor message. Western blot analysis showed the Janus kinase (JAK)/ Signal Transducers and Activators of Transcription (STAT) pathway was activated and an increase …

Natural And Exogenous Genome Editing In Wiskott-Aldrich Syndrome Patient Cells, Tamara J. Laskowski

Dissertations and Theses (Open Access)

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency disease characterized by thrombocytopenia, recurrent infections and increased autoimmunity. This disease is caused by mutations in the WAS gene (WAS) which encodes for the WAS protein (WASp), exclusively expressed in hematopoietic cells and required for proper platelet production and lymphoid cell function. Approximately 11% of patients with WAS exhibit a phenomenon called Somatic Revertant Mosaicism which is characterized by the presence of lymphocytes which naturally revert back to normal phenotype by restoring WASp expression. To date, the mechanisms of this naturally-occurring gene therapy remains poorly understood, and the full extent …

Functional Analysis Of Cytosolic Hsp70 Nucleotide Exchange Factor Networks In Yeast, Jennifer Lynn Abrams

Dissertations and Theses (Open Access)

The Hsp70 class of molecular chaperones play critical roles in protein homeostasis via an ATP-dependent folding cycle. Cytosolic Hsp70s in the budding yeast Saccharomyces cerevisiae, Ssa and Ssb, interact with up to three distinct nucleotide exchange factors (NEFs) homologous to human counterparts; Sse1/Sse2/HSP110, Fes1/HspBP1, and Snl1/Bag1. In an effort to understand the differential functional contributions of the cytosolic NEFs to protein homeostasis (“proteostasis”), I carried out comparative genetic, biochemical and cell biological analyses. For these studies, I developed protocols to monitor protein disaggregation and reactivation in a near real-time coupled assay that revealed the importance of aggregate dynamics in the …

Characterization Of Ftsa-Ftsn Interaction During Escherichia Coli Cell Division, [email protected] K. Busiek

Dissertations and Theses (Open Access)

Division of a bacterial cell into two equal daughter cells requires precise assembly and constriction of the division machinery, or divisome. The Escherichia coli divisome includes nearly a dozen essential cell division proteins that assemble at midcell between segregating sister chromosomes. FtsZ, a homolog of eukaryotic tubulin, is the first essential cell division protein to localize at midcell where it polymerizes into a ring-shaped scaffold (Z ring). Establishment of the Z ring is required for recruitment of downstream cell division proteins including FtsA, a cytoplasmic protein that tethers the Z ring to the inner membrane. Following localization of FtsA and …

Investigation Of Rice Bran Derived Anti-Cancer Pentapeptide For Mechanistic Potency In Breast Cancer Cell Models, Ruiqi Li

Graduate Theses and Dissertations

Bioactive peptides derived from food sources with anti-proliferative properties against cancer have drawn more attention in recent years. A pentapeptide derived from rice bran has shown anti-proliferative propertiesagainst human breast cancer cells. The objective of this study was to investigate the mechanistic action of the pentapeptide-induced apoptosis in breast cancer cell models (MCF-7 and MDA-MB-231). The growth inhibition activity of the pentapeptide was

evaluated by MTS[3-(4,5-dimethylthiazol-2-yl)-5-(3- arboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt] assayand trypan blue assay in a dose- and time-dependent manner.

The apoptotic properties of pentapeptide-induced apoptosis on cancerous breast cells were evaluated by morphological changes, DNA fragmentation, and caspases-3/7, -8,and -9 …

Combined Metagenomic And Phenomic Approaches Identify A Novel Salt Tolerance Gene From The Human Gut Microbiome, Eamon Culligan, Julian R. Marchesi, Colin Hill, Roy D. Sleator

Department of Biological Sciences Publications

In the current study, a number of salt-tolerant clones previously isolated from a human gut metagenomic library were screened using Phenotype MicroArray (PM) technology to assess their functional capacity. PM's can be used to study gene function, pathogenicity, metabolic capacity and identify drug targets using a series of specialized microtitre plate assays, where each well of the microtitre plate contains a different set of conditions and tests a different phenotype. Cellular respiration is monitored colorimetrically by the reduction of a tetrazolium dye. One clone, SMG 9, was found to be positive for utilization/transport of L-carnitine (a well-characterized osmoprotectant) in the …

Noncanonical Role For The Host Vps4 Aaa+ Atpase Escrt Protein In The Formation Of Tomato Bushy Stunt Virus Replicase, Daniel Barajas, Isabel Fernández De Castro Martín, Judit Pogany, Cristina Risco, Peter D. Nagy

Plant Pathology Faculty Publications

Assembling of the membrane-bound viral replicase complexes (VRCs) consisting of viral- and host-encoded proteins is a key step during the replication of positive-stranded RNA viruses in the infected cells. Previous genome-wide screens with Tomato bushy stunt tombusvirus (TBSV) in a yeast model host have revealed the involvement of eleven cellular ESCRT (endosomal sorting complexes required for transport) proteins in viral replication. The ESCRT proteins are involved in endosomal sorting of cellular membrane proteins by forming multiprotein complexes, deforming membranes away from the cytosol and, ultimately, pinching off vesicles into the lumen of the endosomes. In this paper, we show an …

Examination Of Human Embryonic Kidney Cells And Cardiomyocytes Using Glass Microcarrier Beads And Scanning Electron Microscopy, Jaekook Sim

Undergraduate Research Symposium

Alterations of sarcomeric proteins lead to disruption of myofilaments and are associated with hypertrophic cardiomyopathy. We have identified a genetically altered mouse strain with an elevated level of actin associated protein and are characterizing the nature of the hypertrophy by examining the cultured cells on glass microcarrier beads using Scanning Electron Microscopy (SEM). Beads provide a surface for cell growth and division and subsequent analysis of myocyte morphology. This study requires the establishment of primary embryonic cardiomyocyte culture which is difficult to establish. Therefore in initial studies to acquire the necessary tissue culture skill, we cultured Human Embryonic Kidney (HEK) …

Investigations On The Effects Of Palmitate On Neuronal Cells, Ryan Gelsinger

Seton Hall University Dissertations and Theses (ETDs)

Many studies have demonstrated that increased levels of free fatty acids (FFAs) are associated with increased apoptosis in hepatocytes, podocytes, myocytes, and pancreatic islet cells. However, the effects of FAAs on neuronal cell function are not well characterized. In this study, mouse neuroblastoma cells from the Neuro-2a (N2a) cell line were treated with either bovine serum albumin (BSA) or different concentrations of BSA-conjugated palmitate (PA) and examined cell viability using MTT assay. Concentrations of PA at or above 200 μM in the growth media were associated with a decrease in cell viability. In order to examine whether N-acetylcysteine (NAC) or …

Regulatory Roles Of Facit Collagens Xii And Xiv In Cornea Stromal And Endothelial Development And Function, Chinda Hemmavanh

USF Tampa Graduate Theses and Dissertations

Purpose:

Corneal transparency depends upon the precise organization of corneal stromal extracellular matrix and corneal endothelial function. Stromal structure and extracellular matrix organization is responsible for proper refraction of light into the eye. The corneal endothelium is responsible for pumping excess fluid out of the cornea, effectively maintaining corneal hydration and thickness. Corneal transplantation is the current form of treatment for corneal endothelial and stromal dystrophies. The mechanisms controlling stromal collagen fibril packing and organization into orthogonal layers as well as maturation of the endothelium into a fully functioning cellular layer are unknown. Collagens XII and XIV, fibril associated collagens …

Photobiostimulation In C. Elegans As A Model For Low Level Light Therapy, Michael J. Spoto, Daryl D. Hurd

Science Scholars

Low-Level Laser Therapy (LLLT) is a developing therapeutic technique that has been gaining recognition in the scientific community in recent years. Previous experiments performed in LLLT research projects have been primarily mammalian and cell culture based. These experiments have produced results showing accelerated tissue repair. In this experiment, we introduce a new model, Caenorhabitidis elegans, a free-living soil nematode, to be used in LLLT research by testing the effects of exposure of the organism to various wavelengths and intensities of light commonly used in LLLT. C. elegans was shown to respond to photobiostimulation when exposed to specific wavelengths of …

Analysis Of The Regulation And Function Of Cip2a To Identify Candidate Biomarkers For Prostate Cancer, Diana Savoly

Graduate School of Biomedical Sciences Theses and Dissertations

Protein Phosphatase 2A (PP2A) is a tumor suppressor involved in the regulation of several signaling pathways and the cell cycle. PP2A becomes inactivated by several inhibitors, including Cancerous Inhibitor of PP2A (CIP2A). CIP2A has been identified as an oncogene, which is over-expressed in cancers and inhibits PP2A through direct interaction. CIP2A is recognized as a biomarker for cancer; however, it is not cancer-specific. Therefore, we identified and examined the use of CIP2A-regulated proteins as potential biomarkers in prostate cancer to better diagnose prostate cancer in patients. Currently, Prostate Specific Antigen (PSA) is widely used to detect prostate cancer; however, it …

Structural And Functional Analysis Of Harv1 Lipid Binding, Jamie Francisco

Graduate School of Biomedical Sciences Theses and Dissertations

Cardiovascular disease (CVD) has the highest mortality rate worldwide and is considered epidemic in the United States. Statins as the primary and almost sole method of treatment for cholesterol-related CVD, but they have limitations. Proper sterol transport is needed to maintain normal blood lipid levels. Studies have shown that misregulation of lipid trafficking aids in the progression of CVD and in the activation of the unfolded protein response (UPR). Misregulation of lipid and sterol homeostasis also results in the loss of lipid rafts, known cellular signaling hubs and major components of ER associated membrane contact sites. Arv1 is a highly …

Vaccinia Virus Flll Mediated Expedition Of Tanapoxvirus Replication In Cell Culture, Yih Wen Goh

Masters Theses

Tanapoxvirus (TPV) produces large but slow-forming plaques as opposed to vaccinia virus (VACV) that forms similar large plaques but more rapidly. A number of genes were identified in VACV, inclucding FllL, A33R, A34R and A36R that contribute to the regulation of virus release and dissemination, and are particularly responsible for the induction of actin tails. Among them, TPV lacks homologs of the FllL and A36R genes. F11Lmediated inhibition of RhoA-mDia signaling was shown to enhance the microtubules dynamics and modulates the cortical actin that assisted in the release of progeny virus from infected cells. To understand the possible effects of …

Neurotrophins And Their Effects On Breast Cancer Cell Proliferation And Migration, Kayla Elise Minser

Open Access Theses

Cancer is a large health issue in all parts of the world. In the United States alone, approximately 1 in 4 deaths are cancer related. Breast cancer is a particularly prevalent form, accounting for a little over 14 percent of all cancer incidence. The largest obstacle to overcome for breast cancer morbidity is metastasis. Over 90 percent of all breast cancer related deaths are due to metastasis. Because metastasis is a complex, multi-step process, it is difficult to treat. A recent observation in the Kirshner lab has revealed a type of phenotypic plasticity, where migratory cancer cells have a neuronal-like …

Mitochondrial Reactive Oxygen Species (Ros): Which Ros Is Responsible For Cardioprotective Signaling?, Anders Olav Garlid

Dissertations and Theses

Mitochondria are the major effectors of cardioprotection by procedures that open the mitochondrial ATP-sensitive potassium channel (mitoK_ATP), including ischemic and pharmacological preconditioning. MitoK_ATP opening leads to increased reactive oxygen species (ROS), which then activate a mitoK_ATP-associated PKCε, which phosphorylates mitoK_ATP and leaves it in a persistent open state (Costa, ADT and Garlid, KD. Am J Physiol 295, H874-82, 2008). Superoxide (O₂^•-), hydrogen peroxide (H₂O₂), and hydroxyl radical (HO^•) have each been proposed as the signaling ROS but the identity of the ROS responsible for this …

Characterization Of Iron Response In Gynecological Cell Lines, Kyle A. Bauckman

USF Tampa Graduate Theses and Dissertations

Ovarian carcinoma afflicts over 22,000 women each year with a 5 year survival rate of only 18% for stage IV patients [23]. Current treatment options are limited due to high rates of drug resistance and recurrence. Further, the identity of "precursor lesions" which give rise to various subclasses of epithelial ovarian cancer has been evasive. This is due to discovery of the cancer at already an advanced stage. Interestingly, endometriosis a benign but invasive gynecological disease has been described as a "precursor lesion" in the development of specific subtypes of ovarian cancer. Endometriotic cyst development involves the accumulation of "old …

Exploration Of Mutations In Erythroid 5-Aminolevulinate Synthase That Lead To Increased Porphyrin Synthesis, Erica Jean Fratz

USF Tampa Graduate Theses and Dissertations

5-Aminolevulinate synthase (ALAS; EC 2.3.1.37) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the first committed step of heme biosynthesis in animals, the condensation of glycine and succinyl-CoA yielding 5-aminolevuliante (ALA), CoA, and CO2. Murine erythroid-specific ALAS (mALAS2) variants that cause high levels of PPIX accumulation provide a new means of targeted, and potentially enhanced, photosensitization. Transfection of HeLa cells with expression plasmids for mALAS2 variants, specifically for those with mutated mitochondrial presequences and a mutation in the active site loop, caused significant cellular accumulation of PPIX, particularly in the membrane. Light treatment of HeLa cells expressing mALAS2 variants revealed …

A Central Role For Vimentin In Regulating Repair Function During Healing Of The Lens Epithelium, A. S. Menko, B. M. Bleaken, A. A. Libowitz, L. Zhang, Mary Ann Stepp, J. L. Walker

Anatomy and Regenerative Biology Faculty Publications

Mock cataract surgery provides a unique ex vivo model for studying wound repair in a clinically relevant setting. Here wound healing involves a classical collective migration of the lens epithelium, directed at the leading edge by an innate mesenchymal subpopulation of vimentin-rich repair cells. We report that vimentin is essential to the function of repair cells as the directors of the wound-healing process. Vimentin and not actin filaments are the predominant cytoskeletal elements in the lamellipodial extensions of the repair cells at the wound edge. These vimentin filaments link to paxillin-containing focal adhesions at the lamellipodial tips. Microtubules are involved …

Molecular Pap Biomarkers For Cervical Cancer Risk Assessment In Thinprep® Clinical Specimens, Jennifer Taylor

Graduate School of Biomedical Sciences Theses and Dissertations

Approximately 500,000 patients are diagnosed with cervical cancer worldwide each year, thus making it the second most common cause of cancer-related deaths in women. Persistent high-risk human papillomavirus (HR-HPV) infections induce cervical dysplasia by increasing the expression of two viral oncogenes, E6 and E7. Utilization of the Papanicolaous smear test (Pap test) has contributed to a decrease in morbidity and mortality of cervical cancer; however, subjective analysis of cell morphology with a limited amount of cells has led to a substantial rate of false positive and false negative diagnoses. A more objective and sensitive diagnostic tool for the detection of …

Chip-Seq And Rna-Seq Reveal An Amrz-Mediated Mechanism For Cyclic Di-Gmp Synthesis And Biofilm Development By Pseudomonas Aeruginosa, Christopher J. Jones, David Newsom, Benjamin Kelly, Yasuhiko Irie, Laura K. Jennings, Binjie Xu, Dominique H. Limoli, Joe J. Harrison, Matthew R. Parsek, Peter White, Daniel J. Wozniak

Biology Faculty Publications

The transcription factor AmrZ regulates genes important for P. aeruginosa virulence, including type IV pili, extracellular polysaccharides, and the flagellum; however, the global effect of AmrZ on gene expression remains unknown, and therefore, AmrZ may directly regulate many additional genes that are crucial for infection. Compared to the wild type strain, a ΔamrZ mutant exhibits a rugose colony phenotype, which is commonly observed in variants that accumulate the intracellular second messenger cyclic diguanylate (c-di-GMP). Cyclic di-GMP is produced by diguanylate cyclases (DGC) and degraded by phosphodiesterases (PDE). We hypothesized that AmrZ limits the intracellular accumulation of c-di-GMP through transcriptional repression …

Immature Myeloid Cells Promote Tumor Formation Via Non-Suppressive Mechanism, Myrna Lillian Ortiz

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Although there is ample evidence linking chronic inflammation with cancer, the cellular mechanisms involved in early events leading to tumor development remain unclear. Myeloid cells are an intricate part of inflammation. They consist of mature cells represented by macrophages, dendritic cells and granulocytes and a population of Immature Myeloid Cells (IMC), which in healthy individuals are cells in transition to mature cells. There is a substantial expansion of IMC in cancer and many other pathological conditions which is associated with pathologic activation of these cells. As a result, these cells acquire the ability to suppress immune responses and are …

Direct-To-Consumer Genetic Testing In The College Classroom: Knowledge, Attitudes, And Concerns Of Introductory Biology Students, Nicanor Austriaco

Biology Faculty Publications

Pioneered by companies like 23andMe.com, deCODEme.com, and Navigenics.com, direct-to-consumer genetic testing refers to genetic tests that are marketed directly to consumers via television, print media, or the Internet. This kind of testing provides access to a customer’s genetic information without necessarily involving either a medical health care professional or a genetic counselor in the process. In recent years, a course offered to medical and graduate students at Stanford University has included an option for students to undergo personal genotyping, raising the possibility that direct-to-consumer genetic testing could also be incorporated into undergraduate biology courses to enhance student learning. In this …

Deletion Of Aif1 But Not Of Yca1/Mca1 Protects Saccharomyces Cerevisiae And Candida Albicans Cells From Caspofungin-Induced Programmed Cell Death, Nicanor Austriaco, Christopher Chin, Faith Donaghey, Kathrine Helming, Morgan Mccarthy, Stephen Rogers

Biology Faculty Publications

Caspofungin was the first member of a new class of antifungals called echinocandins to be approved by a drug regulatory authority. Like the other echinocandins, caspofungin blocks the synthesis of β(1,3)-D-glucan of the fungal cell wall by inhibiting the enzyme, β(1,3)-D-glucan synthase. Loss of β(1,3)-D-glucan leads to osmotic instability and cell death. However, the precise mechanism of cell death associated with the cytotoxicity of caspofungin was unclear. We now provide evidence that Saccharomyces cerevisiae cells cultured in media containing caspofungin manifest the classical hallmarks of programmed cell death (PCD) in yeast, including the generation of reactive oxygen species (ROS), the …

Lipid Dependence In Ras-Driven Tumors, Darin Salloum

Dissertations, Theses, and Capstone Projects

Over past decade, metabolic alterations in cancer cells have received a substantial amount of interest. It had been established that cancer cells undergo a significant amount of metabolic alterations, and some of these alterations are similar to those in normal highly proliferative cells. However, it is becoming more apparent that many of the metabolic alterations are specific to particular oncogenic signaling pathways. Although altered metabolic machinery makes cancer cells more efficient at promoting growth when nutrients are supplied at the sufficient amounts, the dependency of cancer cells on particular metabolic reprogramming deems cancer cells susceptible to disruptions within metabolic network. …

The Effect Of Drying On Desiccation Tolerance And Late Embryogenesis Abundant Protein Gene Expression In Immature Seeds Of Phalaenopsis Amabilis, Huijing Zhu

Masters Theses

Orchidaceae as the most diverse family of flowering plants are endangered due to losing habitats or destruction of their unique symbiotic living style. Long-term seed storage banks can be a solution for threatened plant species but the stored seeds must tolerate extreme drying and cold. This ability is acquired during the last stage (maturation drying) of seed development and is correlated with a decline in water content and expression of the Late Embryogenesis Abundant (LEA) protein genes. Our goal is to investigate if premature orchid seeds can be artificially induced to become desiccation tolerant and the potential role of LEA …

Candida Albicans Als5p Amyloid In Host-Microbe Interactions: A Ceanorhabditis Elegans Study, Michael Bois

Dissertations, Theses, and Capstone Projects

Candida albicans, a dimorphic fungus and an opportunistic pathogen, possesses a myriad of adherence factors including members of the agglutinin-like sequence (Als) family of mannoproteins. The adhesin Als5p mediates adhesion to many substrates, and is upregulated during commensal interactions, but is downregulated during active C. albicans infections[1]. An amyloid forming core sequence at residues 325-331 has been shown to be important for Als5p function, because a single amino acid substitution at position 326 (V326N) greatly reduces Als5p-mediated adherence[2]. We evaluated the role of Als5p in host-microbe interactions, using Caenorhabditis elegans as a host model and feeding them Saccharomyces cerevisiae expressing …

Polymerase Alpha Components Associate With Telomeres To Mediate Overhang Processing, Raffaella Diotti

Dissertations, Theses, and Capstone Projects

Telomeres consist of TTAGGG repeats, which end with a 3' G-overhang and are bound by a six-protein complex, known as Shelterin. In humans, telomeres shorten at each cell division, unless telomerase is expressed and able to add telomeric repeats to the 3' G-overhang. However, for effective telomere maintenance, the DNA strand complementary to that made by telomerase must be synthesized. In this study, I focused on the Polα/primase complex, in particular the subunits p68 (POLA2, the regulatory subunit) and p180 (Polα, the catalytic subunit), and their potential roles at telomeres. I was able to detect p180, p68 and OBFC1, a …

The Sex Of The Cell Dictates Its Response, Carlos Ganesh Penaloza

Dissertations, Theses, and Capstone Projects

Male and female differences in frequency of occurrence in disease have perplexed scientists for some time. This in part derives from limitations in the systems in which one can evaluate sex differences. At the organismal level, differences can be hidden by a myriad of extensive and complex factors. Additional limitations exist since most biomedical studies are performed almost exclusively on male subjects, as the female hormonal milieu is intrinsically more variable and too troublesome for routine inclusion in research protocols. Research documenting sex differences continues to grow, and while most researchers suggests that sex hormones are at the core of …

Metabolic Checkpoints In Cancer Cell Cycle, Mahesh Saqcena

Dissertations, Theses, and Capstone Projects

Growth factors (GFs) as well as nutrient sufficiency regulate cell division in metazoans. The vast majority of mutations that contribute to cancer are in genes that regulate progression through the G1 phase of the cell cycle. A key regulatory site in G1 is the growth factor-dependent Restriction Point (R), where cells get permissive signals to divide. In the absence of GF instructions, cells enter the quiescent G0 state. Despite fundamental differences between GF signaling and nutrient sensing, they both have been confusingly referred to as R and therefore by definition considered to be a singular event in G1. Autonomy from …