Cell Biology Commons^™

Chloride Intracellular Channel Proteins Respond To Heat Stress In Caenorhabditis Elegans, Jun Liang, Yakov Shaulov, Cathy Savage-Dunn, Stéphane Boissinot, Tasmia Hoque

Publications and Research

Chloride intracellular channel proteins (CLICs) are multi-functional proteins that are expressed in various cell types and differ in their subcellular location. Two CLIC homologs, EXL-1 (excretory canal abnormal like-1) and EXC-4 (excretory canal abnormal± 4), are encoded in the Caenorhabditis elegans genome, providing an excellent model to study the functional diversification of CLIC proteins. EXC-4 functions in excretory canal formation during normal animal development. However, to date, the physiological function of EXL-1 remains largely unknown. In this study, we demonstrate that EXL-1 responds specifically to heat stress and translocates from the cytoplasm to the nucleus in intestinal cells and body …

Proteomic Analysis Of The Crustacean Molting Gland (Y-Organ) Over The Course Of The Molt Cycle, Talia B. Head

Master's Theses

Molting in crustaceans is a highly complex physiological process involving negative regulation by two paired endocrine glands, the X-organ/sinus gland complex (XO/SG) and the Y-organ (YO). The XO/SG complex is responsible for making molt-inhibiting hormone (MIH) which negatively regulates synthesis of the molting hormones, ecdysteroids, by the YO. Analysis of gene expression in the XOs and YOs has led to the development of a proposed molecular signaling pathway which regulates ecdysteroidogenesis and subsequent molting in crustaceans. In this study, changes in protein abundance in the YO were characterized over the course of a molt cycle (intermolt, early premolt, mid premolt, …

Study Of Regulated Cell Death In Two Systems: Pd-1 In Natural Killer Cells And Rip3 In Neurons, Yu Huang

Dissertations and Theses (Open Access)

Cell death is not only an essential phenomenon in normal development and homeostasis, but also crucial in various pathologies. It is now clear that many types of cell death can be regulated by pharmacological or genetic interventions. These were largely achieved by identifying the molecular mechanisms underlying the regulated cell death (RCD). While in the immune system, RCD needs to be facilitated to help the clearance of pathogens and tumors, in healthy cells, especially the terminally differentiated neurons in the nervous system, it is more desirable to protect cells from dying due to stress under pathological conditions. Thus, understating the …

The Role Of T-Box Proteins In Vertebrate Germ Layer Formation And Patterning, Sushma Teegala

Dissertations, Theses, and Capstone Projects

All of the tissues in triploblastic organisms, with the exception of the germ cells, arise from the three germ layers, ectoderm, mesoderm and the endoderm. The identification of the genes that underlie the differentiation of these layers is crucial to our understanding of development. T-box family proteins are DNA-binding transcriptional regulators that play important roles during germ layer formation in the early vertebrate embryo. Well-characterized members of this family, including the transcriptional activators Brachyury and VegT, are essential for the proper formation of mesoderm and endoderm, respectively. To date, T-box proteins have not been shown to play a role in …

Breaking In And Busting Out: Cell-Penetrating Peptides And The Endosomal Escape Problem, Julia C. Lecher, Scott J. Nowak, Jonathan Mcmurry

Faculty Articles

Cell-penetrating peptides (CPPs) have long held great promise for the manipulation of living cells for therapeutic and research purposes. They allow a wide array of biomolecules from large, oligomeric proteins to nucleic acids and small molecules to rapidly and efficiently traverse cytoplasmic membranes. With few exceptions, if a molecule can be associated with a CPP, it can be delivered into a cell. However, a growing realization in the field is that CPP-cargo fusions largely remain trapped in endosomes and are eventually targeted for degradation or recycling rather than released into the cytoplasm or trafficked to a desired subcellular destination. This …

Butyltin Compounds Alter Secretion Of Interleukin 6 From Human Immune Cells, Shyretha Brown, Wendy Wilburn, Tyesha Martin, Margaret Whalen

Chemistry Faculty Research

Butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT) are organotin compounds that have been used in a variety of industrial applications; as a result, these compounds have been found in human blood. Interleukin (IL)-6 is a proinflammatory mediator that is produced by T lymphocytes and monocytes. It is responsible for immune response regulation as well as tissue repair and cellular growth. Both BTs decrease the ability of human natural killer cells to destroy tumor cells and alter the secretion of proinflammatory cytokines tumor necrosis factor alpha, interferon gamma and IL-1 beta (β) from human lymphocytes ex vivo. Here, we show that …

Stabilization Of The Transcription Factors Slug And Twist By The Deubiquitinase Dub3 Is A Key Requirement For Tumor Metastasis, Yiwei Lin, Yu Wang, Qing Shi, Qian Yu, Cuicui Liu, Jing Feng, Jiong Deng, B. Mark Evers, Binhua P. Zhou, Yadi Wu

Molecular and Cellular Biochemistry Faculty Publications

The Epithelial-mesenchymal transition (EMT) represents a cellular de-differentiation process that provides cells with the increased plasticity required during embryonic development, tissue remodeling, wound healing and metastasis. Slug and Twist are two key EMT transcription factors (EMT-TFs) that are tightly regulated via ubiquitination and degradation. How Slug and Twist escape degradation and become stabilized in cancer cells remains unclear. One plausible mechanism of Slug and Twist stabilization involves removal of ubiquitin by deubiquitinases (DUBs). In this study, we identified Dub3 as a novel DUB for both Slug and Twist. We further found that Dub3 overexpression increased Slug and Twist protein levels …

Inhibition Of Post-Transcriptional Steps In Ribosome Biogenesis Confers Cytoprotection Against Chemotherapeutic Agents In A P53-Dependent Manner, Russell T Sapio, Anastasiya N Nezdyur, Matthew Krevetski, Leonid Anikin, Vincent J Manna, Natalie Minkovsky, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The p53-mediated nucleolar stress response associated with inhibition of ribosomal RNA transcription was previously shown to potentiate killing of tumor cells. Here, we asked whether targeting of ribosome biogenesis can be used as the basis for selective p53-dependent cytoprotection of nonmalignant cells. Temporary functional inactivation of the 60S ribosome assembly factor Bop1 in a 3T3 cell model markedly increased cell recovery after exposure to camptothecin or methotrexate. This was due, at least in part, to reversible pausing of the cell cycle preventing S phase associated DNA damage. Similar cytoprotective effects were observed after transient shRNA-mediated silencing of Rps19, but not …

Molecular Mechanisms Of C-Terminal Eps15 Homology Domain Containing (Ehd) Protein Function, Kriti Bahl

Theses & Dissertations

Endocytic trafficking is not only an essential process for the maintenance of cellular homeostasis but also plays a vital role in regulating diverse cellular processes such as signaling, migration and cell division. The C-terminal Eps 15 Homology Domain proteins (EHD1-4) play pivotal roles in regulating distinct steps of endocytic trafficking. Among the EHDs, EHD2 is disparate both in terms of sequence homology (70%) and its subcellular localization at the caveolae. The crystal structure of EHD2 has been solved and it contains an unstructured loop consisting of two proline-phenylalanine (PF) motifs: KPFRKLNPF. However, the other paralogs EHD1, …

T-Time: A Data Repository Of T Cell And Calcium Release-Activated Calcium Channel Activation Imagery, Cody Arbuckle, Milton L. Greenberg, Adrienne Bergh, Rene German, Nick Sirago, Erik J. Linstead

Mathematics, Physics, and Computer Science Faculty Articles and Research

BACKGROUND: A fundamental understanding of live-cell dynamics is necessary in order to advance scientific techniques and personalized medicine. For this understanding to be possible, image processing techniques, probes, tracking algorithms and many other methodologies must be improved. Currently there are no large open-source datasets containing live-cell imaging to act as a standard for the community. As a result, researchers cannot evaluate their methodologies on an independent benchmark or leverage such a dataset to formulate scientific questions.

FINDINGS: Here we present T-Time, the largest free and publicly available data set of T cell phase contrast imagery designed with the …

The Cul3 Ubiquitin Ligase: An Essential Regulator Of Diverse Cellular Processes, Brittney Marie Davidge

Dissertations and Theses

Cul3 forms E3 ubiquitin ligase complexes that regulate a variety of cellular processes. This dissertation describes Cul3's role in several of these pathways and provides new mechanistic details regarding the role of Cul3 in eukaryotic cells. Cyclin E is an example of a protein that is regulated in a Cul3-dependent manner. Cyclin E is a cell cycle regulator that controls the beginning of DNA replication in mammalian cells. Increased levels of cyclin E are found in some cancers, in addition, proteolytic removal of the cyclin E N-terminus occurs in some cancers and is associated with tumorigenesis. Cyclin E levels are …

Molecular Mechanisms Of Dna Replication Initiation In Hpvs With Genetic Variations Leading To Cellular Carcinogenesis, Gulden Yilmaz

Graduate School of Biomedical Sciences Theses and Dissertations

Human papillomaviruses are a vast family of double-stranded DNA viruses containing non-carcinogenic and carcinogenic types, whose crucial differences remain unknown, except for the difference in the frequency of DNA replication. The human papillomavirus (HPV) E2 protein regulates the initiation of viral DNA replication and transcription. Its recognition and binding to four 12 bp palindromic sequences in the viral origin is essential for its function. Little is known about the DNA binding mechanism of the E2 protein found in HPV types that have low risk for oncogenicity (low-risk) as well as the roles of various elements of the individual binding sites. …

Chaperoning Ef Hands That Shape Calcium Response: Ncald, Hpca And S100b, Jingyi Zhang

Graduate School of Biomedical Sciences Theses and Dissertations

All organisms have an internal clock with a defined period between repetitions of activities. The period for circadian clock in human is 24.5 hours, while in mouse and rat, it is 23.5 hours. However, all organisms are forced to be in synchronization with their environment. A major environmental force that resets the internal clock to 24 hours is light. This phenomenon is defined as “light entrainment” or “phase-setting”. It is unclear how this entrainment process occurs. Studies from this laboratory indicate a role for two neuronal calcium sensor proteins: Neurocalcin  (NCALD) and S100B. For these two genes, mRNA as …

A Naturally Generated Decoy Of The Prostate Apoptosis Response-4 Protein Overcomes Therapy Resistance In Tumors, Nikhil Hebbar, Ravshan Burikhanov, Nidhi Shukla, Shirley Qiu, Yanming Zhao, Kojo S. J. Elenitoba-Johnson, Vivek M. Rangnekar

Radiation Medicine Faculty Publications

Primary tumors are often heterogeneous, composed of therapy-sensitive and emerging therapy-resistant cancer cells. Interestingly, treatment of therapy-sensitive tumors in heterogeneous tumor microenvironments results in apoptosis of therapy-resistant tumors. In this study, we identify a prostate apoptosis response-4 (Par-4) amino-terminal fragment (PAF) that is released by diverse therapy-sensitive cancer cells following therapy-induced caspase cleavage of the tumor suppressor Par-4 protein. PAF caused apoptosis in cancer cells resistant to therapy and inhibited tumor growth. A VASA segment of Par-4 mediated its binding and degradation by the ubiquitin ligase Fbxo45, resulting in loss of Par-4 proapoptotic function. Conversely, PAF, which contains this VASA …

Functional Expression Of Programmed Death-Ligand 1 (B7-H1) By Immune Cells And Tumor Cells, Rachel M. Gibbons Johnson

Biology Publications

The programmed death-1 (PD-1) and its ligand PD-L1 (B7-H1) signaling pathway has been the focus of much enthusiasm in the fields of tumor immunology and oncology with recent FDA approval of the anti-PD-1 antibodies pembrolizumab and nivolumab and the anti-PD-L1 antibodies durvalumab, atezolimuab, and avelumab. These therapies, referred to here as PD-L1/ PD-1 checkpoint blockade therapies, are designed to block the interaction between PD-L1, expressed by tumor cells, and PD-1, expressed by tumor-infiltrating CD8+ T cells, leading to enhanced antitumor CD8+ T cell responses and tumor regression. The influence of PD-L1 expressed by tumor cells on antitumor CD8+ T cell …

Characterizing The Influence Of Gap Junction Communication On Cell Volume Dynamics, Bona Mu

Biology Theses

Cell volume changes are associated with both normal and disease processes, and can serve as a signal for altering cell activities. Most cell types in a multicellular organism express gap junction channels that allow for the direct transfer of ions, metabolites, and other small molecules between neighboring cells. Little is known about the potential role of gap junctions in modulating cell volume dynamics. The present study characterizes what happens to the swelling rates of fast swelling and slow swelling cells when they are coupled together by gap junctions. The initial hypothesis was that water transport through gap junctions from a …

Linear Dna-Linked Nanoparticle Building Blocks (Nblocks) For Modular Self-Assembly Of Nanostructures, Jakob Thomas Hockman

Graduate Theses and Dissertations

Controlling the shapes and sizes of nanomaterials often enables controlling their properties for certain applications. The most promising methods for controlling the shapes and sizes of nanostructures use base-pairing between complementary DNA strands to self-assemble nanostructures from DNA and nanoparticles. DNA Brick-based self-assembly is a particularly useful method for creating DNA nanostructures. It offers a large amount of control over the final shapes and sizes because it uses building blocks that are anisotropic and have predictable geometry. However, this control has not been extended to the self-assembly of nanostructures from nanoparticles. Applying DNA Brick based self-assembly to the self-assembly of …

Eye Repair In Xenopus Laevis, Cindy Xuan-Mai Kha

UNLV Theses, Dissertations, Professional Papers, and Capstones

Eye development in vertebrates of complex steps that include specific interactions of the neuroectoderm and overlying head ectoderm. The African clawed frog, Xenopus laevis (X. laevis), has a well-characterize eye developmental pathway and is an established model for eye regeneration research. Additionally, Xenopus frogs have high regenerative abilities to regenerate individual eye tissues such as the retina, lens, and cornea. However, it was previously shown that the removal of the specified eye field during the neurulation stage or an eye during the swimming tadpole stage does not permit an eye to regenerate. Here we will describe a model for investigating …

Gcn5 Impacts Fgf Signaling At Multiple Levels And Activates C-Myc Target Genes During Early Differentiation Of Embryoid Bodies, Li Wang

Dissertations and Theses (Open Access)

Precise control of gene expression during development is orchestrated by transcription factors, signaling pathways and co-regulators, with complex cross-regulatory events often occurring. Growing evidence has identified chromatin modifiers as important regulators for development as well, yet how particular chromatin modifying enzymes affect specific developmental processes remains largely unclear. Embryonic stem cells (ESCs) are self-renewing, pluripotent, and have the abilities to generate almost all cell types in adult tissues. The dual capacity of ESCs to self-renew and differentiate offers unlimited potential for studying gene regulation events at specific developmental stages in vitro that parallel developmental events during embryogenesis in vivo. …

Basigin-2 Mediated Activation Of Erk1/2 Signaling In Human Glioblastoma Multiforme Cells, Erik R. Peterson

All NMU Master's Theses

Glioblastoma multiforme (GBM) is the most common malignant form of human brain cancer. GBM tumor cells overexpress the protein Basigin (Bsg) at the cell surface where it contributes to malignancy via stimulation of matrix metalloproteinase (MMP) expression in surrounding normal tissues, resulting in the degradation of the extracellular matrix (ECM) surrounding tumors, promoting remodeling of the tumor borders, stimulating growth. In work by Belton et al. (2008), human uterine endometrial cells treated with a recombinant form of human basigin possessing the extracellular domain of the Bsg protein (rBsg-ECD) showed activation of the Mitogen-Activated Protein Kinase (MAPK) signaling pathway proteins, ERK1/2. …