Cell Biology Commons^™

Restructuring Of The Axon Initial Segment In Mouse Models Of Neurodevelopmental Disorders, Rachel Ali Rodriguez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neurodevelopmental disorders (NDDs) affect more than 36% of children in countries with low- and middle- incomes (Boivin, 2015; McCoy, 2016). Interestingly, these heterogeneous disorders share a high incidence of epileptic seizures, suggesting a shared pathology. Seizures result when neuronal firing activity becomes disturbed and neurons fire excessively or in unregulated patterns. A key site in the control of neuronal firing patterns is the axon initial segment (AIS), where the local density of proteins and the morphology of the AIS in part determine the firing of neurons. We hypothesized that a disruption in the morphology and/or composition of the AIS can …

Uncovering The Zeb1 Interactome To Identify Novel Regulators Of Metastatic Non-Small Cell Lung Cancer, Roxsan Manshouri

Dissertations & Theses (Open Access)

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in the United States, due in part to the robust affinity of lung cancer cells to metastasize. Understanding the processes that contribute to metastasis provides promise for the discovery of novel therapeutic targets. Epithelial-tomesenchymal transition (EMT) is a proposed model for the initiation of metastasis. During EMT cell adhesion and polarity is reduced, allowing epithelial cancer cells to dissociate from the primary tumor and invade distant organs. The transcription factor zinc finger E-box-binding homeobox 1 (ZEB1) has been reported to uniquely correlate with NSCLC disease progression and to …

Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr

Graduate Theses and Dissertations

Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …

The Role Of Membrane Domains In Protein And Lipid Sorting During Endocytic Traffic, Blanca B. Diaz-Rohrer

Dissertations & Theses (Open Access)

The lipid and protein composition of the plasma membrane (PM) must be tightly controlled to maintain cellular functionality, despite constant, rapid endocytosis. Because de novo synthesis of proteins and lipids is energetically costly, the cell depends on active recycling to return endocytosed membrane components back to the PM. For most proteins, the mechanisms and pathways of their PM retention remain unknown. The work presented here shows that association with ordered membrane microdomains is fully sufficient for PM recycling and that abrogation of raft partitioning leads to their degradation in lysosomes. These findings support a model wherein ordered membrane domains mediate …

Updating Molecular Diagnostics For Detecting Methicillin- Susceptible And Methicillin-Resistant Staphylococcus Aureus Isolates In Blood Culture Bottles, Fred C. Tenover, Isabella A. Tickler, Victoria M. Le, Scott Dewell, Rodrigo E. Mendes, Richard V. Goering, Mrsa Consortium

Biology Faculty Publications

Molecular diagnostic tests can be used to provide rapid identification of staphylococcal species in blood culture bottles to help improve antimicrobial stewardship. However, alterations in the target nucleic acid sequences of the microorganisms or their antimicrobial resistance genes can lead to false-negative results. We determined the whole-genome sequences of 4 blood culture isolates of Staphylococcus aureus and 2 control organisms to understand the genetic basis of genotypephenotype discrepancies when using the Xpert MRSA/SA BC test (in vitro diagnostic medical device [IVD]). Three methicillin-resistant S. aureus (MRSA) isolates each had a different insertion of a genetic element in the staphylococcal cassette …

Equine Hoof Stratum Internum K14+Cd105+ Progenitor Cells: Culture, Characterization, And Model Of Epithelial To Mesenchymal Transition, Qingqiu Yang

LSU Doctoral Dissertations

For the potential benefit of progenitor cells to be realized in cell-based clinical therapies, it is vital to investigate the mechanism between progenitor cells and abnormal tissue formation. Laminitis is a fatal condition that is often presented by equine hoof inflammation and hoof tissue disarrangement. The persistence of abnormal tissue formation after the resolution of equine laminitis suggests there is progenitor cell compromise. So far, there is limited information about equine hoof progenitor cells and the effects of inflammation on hoof progenitor cells. To pursue a better understanding of both hoof progenitor cell and hoof growth as well as find …

Regulation Of The Microtubule Cytoskeleton And Cell Wall Development In Arabidopsis Thaliana, Christy J. Fornero

Theses and Dissertations

Regulation of the cortical microtubule cytoskeleton is critical for organized plant cell division. Arabidopsis ton1 and ton2 mutants display random cell division plane placement and lack the plant-specific cortical microtubule array that encircles the nucleus prior to mitosis. In wild type plants, this preprophase band (PPB) of cortical microtubules precisely marks the future division plane. The specific roles of TON1 and TON2 in PPB formation are not yet known. It is suspected that TON1 Recruiting Motif (TRM) proteins may be involved in TON1 and TON2 recruitment to the PPB. Here we describe results for the targeted disruption of a group …

Dormant Pathogenic Cd4(+) T Cells Are Prevalent In The Peripheral Repertoire Of Healthy Mice, Anna Cebula, Michal Kuczma, Edyta Szurek, Maciej Pietrzak, Natasha Savage, Wessam R. Elhefnawy, Grzegorz Rempala, Piotr Kraj, Leszek Ignatowicz

Computer Science Faculty Publications

Thymic central tolerance eliminates most immature T cells with autoreactive T cell receptors (TCR) that recognize self MHC/peptide complexes. Regardless, an unknown number of autoreactive CD4+Foxp3⁻ T cells escape negative selection and in the periphery require continuous suppression by CD4+Foxp3⁺ regulatory cells (Tregs). Here, we compare immune repertoires of Treg-deficient and Treg-sufficient mice to find Tregs continuously constraining one-third of mature CD4⁺Foxp3⁻ cells from converting to pathogenic effectors in healthy mice. These dormant pathogenic clones frequently express TCRs activatable by ubiquitous autoantigens presented by class II MHCs on conventional dendritic cells, including selfpeptides that select …

Histology Atlas: Basic Mammalian Tissue Types (Biol 105), Joshua Barnes, Daniel J. Yakubov, Corinna Singleman, Nathalia G. Holtzman

Open Educational Resources

This book is a guide to the basic histology lab conducted as a part of the Queens College, CUNY Biology Department Bio105 General Biology: Physiology and Cell Biology course. This course is the first half our two-part series for biology majors. The actives are designed to be conducted over a single 3-hour lab periods which focus on the relationship of form and function of the cellular and organ level anatomy and physiology. Step by step instructions for each slide set are provided for all the key organs.

In addition to the full text of the book, we also provide a …

Total Rna Extraction From Transgenic Flies Misexpressing Foreign Genes To Perform Next Generation Rna Sequencing, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Due to absence of transgenic approaches in Notopthalmus Viridescens (newt), and conservation of genetic machinery across species, we generated transgenic Drosophila melanogaster to misexpress unique genes from newt. Novel newt genes cloned, and inserted at attP site in Drosophila were misexpressed ubiquitously using tubulin Gal-4. Sample (total RNA) for RNA sequencing was collected at 3rd instar larval stage during which major developmental events takes place in Drosophila. Total RNA was extracted, and purified using RNA clean and ConcentratorTM. RNA quality was quantitated by calculating absorbance at 260 nm (A260) and 280 nm (A280) wavelengths using Nanodrop 2000 spectrophotometer. Good quality …

Fetal Pig Dissection Manual (Biol 105), Nathalia G. Holtzman, Daniel J. Yakubov

Open Educational Resources

This book is a guide to the basic fetal pig dissection conducted as a part of the Queens College, CUNY Biology Department Bio105 General Biology: Physiology and Cell Biology course. This course is the first half our two-part series for biology majors. The actives are designed to be conducted over a three- 3-hour lab periods which focus on the relationship of form and function of the pig anatomy and physiology. Step by step instructions for the dissection are provided along with some microscopy tasks to look at the histology of key organs.

In addition to the full text of the …

Comparative Transcriptomic Analysis And Structure Prediction Of Novel Newt Proteins, Abijeet Singh Mehta, Agustin Luz-Madrigal, Jian-Liang Li, Panagiotis A. Tsonis, Amit Singh

Biology Faculty Publications

Notophthalmus viridescens (Red-spotted Newt) possess amazing capabilities to regenerate their organs and other tissues. Previously, using a de novo assembly of the newt transcriptome combined with proteomic validation, our group identified a novel family of five protein members expressed in adult tissues during regeneration in Notophthalmus viridescens. The presence of a putative signal peptide suggests that all these proteins are secretory in nature. Here we employed iterative threading assembly refinement (I-TASSER) server to generate three-dimensional structure of these novel Newt proteins and predicted their function. Our data suggests that these proteins could act as ion transporters, and be involved …

Vanadium Compounds Modulate Osteoblast Proliferation And Function, Bryan Sosa

Seton Hall University Dissertations and Theses (ETDs)

Osteoblastogenesis is an essential part of the bone healing process. Insulin has been shown to improve bone healing in both normal and diabetic bone healing models. In addition, insulin mimetic compounds such as Zinc chloride (ZnCl₂) and Vanadyl acetylacetonate (VAC) have also been shown to improve bone healing in these models as well. The purpose of this study was to determine the effects of vanadium compounds VAC and Vanadium (II) sulfate (VSO₄) in osteoblast proliferation and function. In addition the mechanisms by which growth and function are facilitated by these Vanadium compounds were also evaluated. In …

Assessing The Efficacy Of Seedling Planting As A Forest Restoration Technique In Temperate Hardwood Forests Impacted By Invasive Species, Michaela J. Woods, Meredith Cobb, Katie Hickle

Biology Faculty Publications

The emerald ash borer (Agrilus planipennis Fairmaire; EAB) is an invasive insect that causes mortality of trees in the genus Fraxinus, creating canopy gaps that may facilitate invasion by exotic plants. Planting native tree seedlings under EAB-infested Fraxinus may accelerate succession and preclude invasive plant expansion; however, the effectiveness of this approach has not been experimentally tested. We assessed understory seedling planting of Quercus rubra, Carya laciniosa, and Juglans cinerea in EAB-infested forests, where the invasive shrub Lonicera maackii (Amur honeysuckle) was removed. We tested whether the use of plastic tree shelters (“tree tubes”) or planting season (fall versus spring) …

An Assessment Of Bsa Protein Hydrogel Biocompatibility In The Vertebrate Intestinal Tract, Ryan Joseph Garde

Theses and Dissertations

The fields of biomedicine and pharmacology have a mission to design methods to treat disease while minimizing adverse side effects using novel drug delivery systems. In developing new therapeutic systems, it is crucial to test that drug delivery systems target pathological cells and tissue and is non-toxic in healthy tissue. One promising method for targeted drug delivery is the use of hydrogels as carriers. Here, we studied the effects of bovine serum albumin (BSA) hydrogel consumption to assess the potential for hydrogel use in treating intestinal disease via oral administration. We investigated intestinal architecture and cell populations following hydrogel treatments …

Sensory Primary Cilium Is A Distinct Signaling Compartment, Rinzhin Tshering Sherpa

Pharmaceutical Sciences (PhD) Dissertations

The primary cilium is a solitary cellular organelle that protrudes from the apical cell membrane. Findings on cilia-dependent mechanosenstation have shown that the primary cilium acts as a transducer of fluid-shear stress into intracellular signaling. Over recent years, studies in primary cilia have intensified after determining a causal relationship between dysfunctional primary cilia and cystic diseases. Along with its mechanosensory function, the primary cilium houses a variety of receptors, ion channels and transporter proteins. Studies in cilia biology have shown that primary cilia are coordinators of signaling pathways such as Hedgehog (Hh), Wnt, and platelet-derived growth factor (PDGF) pathways during …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

Emergence Of Oxacillin Resistance In Stealth Methicillin-Resistant Staphylococcus Aureus Due To Meca Sequence Instability, Richard V. Goering, Erin A. Swartzendriber, Anne E. Obradovich, Isabella A. Tickler, Fred C. Tenover

Biology Faculty Publications

Staphylococcus aureus strains that possess a mecA gene but are phenotypically susceptible to oxacillin and cefoxitin (OS-MRSA) have been recognized for over a decade and are a challenge for diagnostic laboratories. The mechanisms underlying the discrepancy vary from isolate to isolate. We characterized seven OS-MRSA clinical isolates of six different spa types from six different states by whole-genome sequencing to identify the nucleotide sequence changes leading to the OS-MRSA phenotype. The results demonstrated that oxacillin susceptibility was associated with mutations in regions of nucleotide repeats within mecA. Subinhibitory antibiotic exposure selected for secondary mecA mutations that restored oxacillin resistance. …

The ‘Law Of Environmental Dependence’ - Biology And Ethics In The Work Of Ernest Everett Just: + Found – Some 251 Mostly Typed Pages, Theodore Walker

Perkins Faculty Research and Special Events

Abstract-

“The Origin of Man’s Ethical Behavior” (circa October 1941) by Ernest Everett Just and Hedwig A. Schnetzler Just - is an unpublished book manuscript about the biological origins and evolution of ethical behavior, and about “the law of environmental dependence.” Missing since Just’s death in October 1941, it was found and identified in May 2018 among the collected papers of Ernest Everett Just preserved at the Howard University Moorland-Spingarn Research Center in Washington, DC. In addition to the 1996 US postage with the caption “Ernest E. Just, Biologist,” we now have reason to add two new postage stamps with …

Role Of Host Cell B-Catenin During Toxoplasma Gondii Infection, Cameron Ranken

Biology ETDs

The microbial pathogen Toxoplasma gondii is an intracellular protozoan that actively invades host cells and simultaneously creates a specialized parasitophorous vacuole within which the parasite lives and replicates. The parasite molecular machinery that drives establishment of the intracellular niche is relatively well known. However, it is now emerging that Toxoplasma exploits less well-understood host cell components to enable successful infection. Here, we examined the role of host Wnt/β-catenin during T. gondii infection. Using human fibroblasts and a mouse dendritic cell line, we found that infection with Toxoplasma stimulated both upregulation and nuclear localization of β-catenin. Using a transwell experimental approach, …

Development Of A Prolyl Endopeptidase Expression System In Lactobacillus Reuteri To Reduce The Clinical Manifestation Of Celiac Disease, Kara Lynn Jew

Master's Theses

Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are …

Comparison Of Nickel And Cobalt Induced Hypoxic Cell Models Using Cell Proliferation Assay, Melissa Delcasale

Seton Hall University Dissertations and Theses (ETDs)

Hypoxia is an imbalance in oxygen delivery and oxygen consumption, ultimately affecting cell survival. Low levels of oxygen diminish adenosine triphosphate synthesis resulting from a decline in oxidative phosphorylation in the mitochondria, therefore inducing apoptosis and cell death. To create a hypoxia mimicked environment, we used hypoxia mimetic compounds cobalt and nickel to treat human neuroblastoma (NMB) cells. Using hypoxic mimic human neuronal cell models, we examined and compared the effects of compound-induced hypoxia on NMB cell proliferation. The cells were treated with 100mM and 300mM concentrations of each compound at 24- and 48-hour intervals. To investigate cell proliferation, the …

Functional Characterization Of The Ovarian Tumor Domain Deubiquitinating Enzyme 6b, Jasmin M. D'Andrea

USF Tampa Graduate Theses and Dissertations

The posttranslational modification ubiquitination is major regulatory mechanism used throughout cell signaling pathways such as cell cycle regulation and the DNA damage response. As such, the E3 ligases and their deubiquitinating enzyme counterparts, which conjugate and deconjugate ubiquitin to and from protein substrates respectively, must be tightly regulated to prevent aberrant cellular behaviors that could lead to diseases such as cancer.

Of the five families of deubiquitinating enzymes, the Ovarian Tumor Domain (OTU) family is fairly unique and under-studied; many of its family members hold a linkage specificity to certain ubiquitin chains and a number of them have been implicated …

Evolutionary Expansions And Neofunctionalization Of Ionotropic Glutamate Receptors In Cnidaria, Ellen G. Dow

FIU Electronic Theses and Dissertations

Reef ecosystems are composed of a variety of organisms, transient species of fish and invertebrates, microscopic bacteria and viruses, and structural organisms that build the living foundation, coral. Sessile cnidarians, corals and anemones, interpret dynamic environments of organisms and abiotic factors through a molecular interface. Recognition of foreign molecules occurs through innate immunity via receptors identifying conserved molecular patterns. Similarly, chemosensory receptors monitor the environment through specific ligands. Chemosensory receptors include ionotropic glutamate receptors (iGluRs), transmembrane ion channels involved in chemical sensing and neural signal transduction. Recently, an iGluR homolog was implicated in cnidarian immunological resistance to recurrent infections of …

Hippo Signaling In Cancer: Lessons From Drosophila Models, Kirti Snigdha, Karishma Sanjay Gangwani, Gauri Vijay Lapalikar, Amit Singh, Madhuri Kango-Singh

Biology Faculty Publications

Hippo pathway was initially identified through genetic screens for genes regulating organ size in fruitflies. Recent studies have highlighted the role of Hippo signaling as a key regulator of homeostasis, and in tumorigenesis. Hippo pathway is comprised of genes that act as tumor suppressor genes like hippo (hpo) and warts (wts), and oncogenes like yorkie (yki). YAP and TAZ are two related mammalian homologs of Drosophila Yki that act as effectors of the Hippo pathway. Hippo signaling deficiency can cause YAP- or TAZ-dependent oncogene addiction for cancer cells. YAP and TAZ are often activated …

Evaluating The Potential Of Repurposing Commercially Available Drugs For The Treatment Of Viral Infections, Brennan Connor Mcewan

Undergraduate Honors Capstone Projects

Viral infections that are often overlooked as common seasonal illnesses such as influenza can rapidly become a public threat. They threaten society as new, more dangerous strains of these common viruses emerge and as strains develop resistance to current vaccines and antiviral treatments (Kochanek, Murphy, Xu, & Tejada-Vera, 2014). To combat this, the development of antiviral treatments with novel mechanisms of action is essential. Repurposing drugs instead of developing new drugs can save years of development time and hundreds of millions of dollars (DiMasi, Hansen, & Grabowski, 2003). To support the effort to discover drugs with unique mechanisms of action, …

Embryonic Lethality Of Cranial Neural Crest Deletion Of Cdc73, Lilia Shen

Honors Scholar Theses

Hyperparathyroidism-jaw tumor (HPT-JT) syndrome is a disease characterized by parathyroid tumors, renal cysts or tumors, uterine tumors, and ossifying jaw fibromas. The cause of this syndrome is linked to a tumor suppressor gene called Cdc73, which encodes the protein product parafibromin. The loss of proper expression of Cdc73/parafibromin is implicated in the development of the tumors typical of HPT-JT, although the exact mechanisms of tumorigenesis are unclear. In particular, not much is understood about the development of ossifying fibromas (OF) of the jaw in this syndrome. OF is a benign bone neoplasm that can affect the mandible and …

The Molecular Mechanisms Underlying The Cancer Killing Effect Of Interleukin-24, Leah Eshanie Persaud

Dissertations, Theses, and Capstone Projects

Interleukin-24 (IL-24) is an immunomodulatory cytokine that also displays specific anti-tumor effects across many cancer cell types. The tumor suppressor activities of IL-24 include inhibition of angiogenesis, metastasis, toxic autophagy, cancer-specific apoptosis, and sensitization to traditional cancer treatments like chemotherapy and radiation. Overexpression of IL-24 can selectively induce apoptosis in various cancer cells while having no adverse effects on normal cells. Due to this favorable killing effect, IL-24 is currently in phase II clinical trials. There is accumulating evidence that IL-24’s anti-cancer activity is primarily through the endoplasmic reticulum (ER) stress pathway but other pathways leading to cell death are …

Thiol-Based Misfolding: Linking Redox Balance To Cytosolic Proteostasis, Ford Amy

Dissertations & Theses (Open Access)

The eukaryotic cytosolic proteome is vulnerable to changes in proteostatic and redox balance caused by temperature, pH, oxidants and xenobiotics. Cysteine-containing proteins are especially at risk as the thiol side chain is subject to oxidation, adduction and chelation by thiol-reactive compounds. All of these thiol-modifiers have been demonstrated to induce the heat shock response and recruit protein chaperones to sites of presumed protein aggregation in the budding yeast Saccharomyces cerevisiae. However, endogenous targets of thiol stress toxicity responsible for these outcomes are largely unknown. Furthermore, I hypothesize proteins identified as redox-active are prone to misfolding and aggregation by thiol-specific …

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims …