Cell and Developmental Biology Commons^™

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Characterization Of Myod And Myf5 Double-Knockout Muscle Stem Cells During Muscle Development, Andreea Dinicu

University Scholar Projects

MyoD and Myf5 are transcription factors that regulate myogenesis by promoting satellite cell transcription. The two genes are known to display functional redundancy. Both genes are considered myogenic determination genes and are expressed in satellite cells. The fate of myogenic precursors in the absence of both MyoD and Myf5 remains largely unknown. We aimed to begin attaining this knowledge as part of this project. We utilized a CreLoxP system to control the expression of MyoD in mice lacking Myf5. MyoD was knocked out at embryonic day (E) 11.5 during myogenesis. Limbs were collected from experimental mice following tamoxifen injection. …

Detection Of Leukocytes Stained With Acridine Orange Using Unique Spectral Features Acquired From An Image-Based Spectrometer, Courtney J. Hunter

Biomedical Engineering Undergraduate Honors Theses

A leukocyte differential count can be used to diagnosis a myriad blood disorders, such as infections, allergies, and efficacy of disease treatments. In recent years, attention has been focused on developing point-of-care (POC) systems to provide this test in global health settings. Acridine orange (AO) is an amphipathic, vital dye that intercalates leukocyte nucleic acids and acidic vesicles. It has been utilized by POC systems to identify the three main leukocyte subtypes: granulocytes, monocytes, and lymphocytes. Subtypes of leukocytes can be characterized using a fluorescence microscope, where the AO has a 450 nm excitation wavelength and has two peak emission …

The Developmental And Genetic Basis Of Differences In Cave And Surface-Dwelling Forms Of The Crustacean, Asellus Aquaticus, Hafasa Mojaddidi

Dissertations, Masters Theses, Capstones, and Culminating Projects

Currently, there are many gaps in our understanding of the genetic mechanisms responsible for human diseases. One novel method to bridge these gaps is to investigate the naturally occurring variation of wild populations, which is arguably more similar to the genetic complexity present in human disease than artificially induced mutations in model species. Species adapted to subterranean environments often share phenotypic characteristics such as the reduction or complete absence of eyes, reduced pigmentation, and enhanced sensory systems. In order to understand the evolution of these morphological changes, we selected an invertebrate model system the freshwater isopod crustacean Asellus aquaticus, …

Investigating Localization And Activity-Dependent Translation Of Astrocyte Mrna, Rohan Khazanchi

Senior Honors Papers / Undergraduate Theses

Over the past two and a half years, I have studied fundamental aspects of astrocyte biology by investigating the existence and mechanism of astrocyte local translation peripherally around tripartite synapses consisting of pre- and post-synaptic neuron terminals and an associated astrocyte. Astrocytes are critical components of central nervous system synapses (which are predominately tripartite in nature); thus, it is important to consider how astrocyte dysregulation and dysfunction could contribute to the pathogenesis of diseases of synaptic connectivity such as autism spectrum disorders, Alzheimer’s disease, seizure disorders, and more. Overall, my projects involved the development of novel methods to identify astrocyte-specific …

Are Cdi Systems Multicolored, Facultative, Helping Greenbeards?, Elizabeth S. Danka, Erin C. Garcia, Peggy A. Cotter

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Competitive and cooperative interactions between organisms, including bacteria, can significantly impact the composition of a community and the fitness of its members, as well as the fitness of their hosts when communities are living on or within other organisms. Understanding the underlying mechanisms is critical to the development of strategies to control microbiological communities that impact animal and plant health and also for understanding the evolution of social behaviors, which has been challenging for evolutionary biologists. Contact-dependent growth inhibition (CDI) is a phenomenon defined by the delivery of a protein toxin to the cytoplasm of neighboring bacteria upon cell–cell contact, …

Optimizing A Standard Fasting Time For 2-Nbdg Uptake Studies In Murine Breast Cancers, Andrew C. Briley

Biomedical Engineering Undergraduate Honors Theses

Recently, there has been a larger use of 2-NBDG, a fluorescent glucose analog, to study glucose uptake in different cell types. These cell types have ranged anywhere from bacteria to human cancer cells. However, there has yet to be a standard procedure and practice for using 2-NBDG. In this study, our goal is to create a standard fasting time for the cells before introducing 2-NBDG to them. This study uses 4T07 cells, a murine breast cancer cell line, to help optimize this fasting time. These cells were fasted at different time points in order to find the ideal fasting time. …

Role Of Trpv4 In Astrocyte Extracellular Matrix Production, Abby Terlouw

Biomedical Engineering Undergraduate Honors Theses

Traumatic Brain Injury (TBI) is an alteration of brain pathology following damage of the central nervous system (CNS) by an external force. In the CNS, glial scar formation often occurs following TBI, and astrocytes are widely believed to contribute to this scar formation. While the role of astrocytes in extracellular matrix (ECM) production is known, the exact mechanism(s) for this event remain unclear. One possible method is the activation of transient receptor potential vanilloid 4 (TRPV4). TRPV4 is a channel protein found in the astrocyte membrane which has been shown to generate intracellular calcium ions following mechanical stimulation. Previous research …

Determination Of The Effects That A Previously Uncharacterized Secreted Product From Klebsiella Pneumoniae Has On Citrobacter Freundii And Enterobacter Cloacae Biofilms, Cody M. Hastings

Undergraduate Honors Theses

More so than ever, Multiple Drug Resistant (MDR) bacteria are on the rise due to overuse of antibiotics along with natural selection for adaptations that enhance drug-resistant properties. One particular bacterial family, Enterobacteriaceae, has been problematic, exhibiting several bacterial members that have developed a precipitous resistance to modern antibiotics and are also primary causative agents of nosocomial, or hospital acquired, infections. Citrobacter freundii (CF) and Enterobacter cloacae (ECL) are two species of the Enterobacteriaceae family causing significant medical concern due to their role in producing numerous opportunistic infections such as bacteremia, lower respiratory tract infections, urinary tract infections, and endocarditis. …

Uncovering The Identity And Metabolism Of Bacterial Coa-Rna, Joseph R. Spangler

Dissertations

Coenzyme A is an indispensable molecule in all known life with roles in metabolism, gene regulation, and macromolecule synthesis. As CoA is derived from RNA itself, it’s incorporation into RNA by in vitro methods has proven useful in research probing the origin of life based on the RNA World theory. The discovery in contemporary bacteria of RNA modified with CoA, however, provided an unexpected twist to previously well-characterized bacterial systems. The identity of sequences associated with CoA-RNA has been elusive since their discovery in 2009 based on the difficulties in isolation while maintaining RNA quality. The aim of this study …

Identifying The Signaling Mechanisms Of Egfr-Mediated Apoptosis., Nicole Marion Jackson

Electronic Theses and Dissertations

The Epidermal Growth Factor Receptor (EGFR) is a 170-kilodalton transmembrane protein that belongs to the ErbB family of receptor tyrosine kinases. Upon ligand-mediated activation, the EGFR is responsible for cell growth, proliferation, and tissue homeostasis; however, the EGFR is overexpressed in many human malignancies, including MDA-MB-468 cells, a metastatic breast epithelial cell line. Studies within this cell line, and other cell lines characterized with high EGFR levels, have shown that EGF stimulation results in the induction of apoptosis. However, the mechanisms and signaling effectors implicated in this process have yet to be elucidated. The overarching research goal of this dissertation …

Cyclin B1 Mediates The Effect Of Uchl1 In Promoting Cell Cycle Progression In Uterine Papillary Serous Carcinoma, Suet Ying Kwan

Dissertations and Theses (Open Access)

Uterine papillary serous carcinoma (UPSC) is an aggressive form of endometrial cancer with poor survival rates and a high risk of recurrence. The rarity of UPSC poses challenges to the discovery of novel targeted therapies. Therefore, the purpose of this dissertation was to identify novel therapeutic targets that could aid in the management of UPSC. To do so, we began with the relatively large cohort of UPSC cases in the TCGA data set, which was used to identify differentially expressed genes between UPSC and low-grade endometrioid endometrial carcinoma (EEC) and normal tissue.

We identified Ubiquitin Carboxyl-Terminal Hydrolase L1 (UCHL1 …

Phopsphorylation And Ubiquitin Modification At Dna Damage Sites In Response To Double-Strand Breaks, Atanu Paul

Dissertations and Theses (Open Access)

Genomes of all organisms are continuously damaged by numerous exogenous and endogenous sources leading to different kinds of DNA lesions, which if not repaired efficiently may trigger wide-scale genomic instability, a hallmark of cancer development. To overcome this, cells have evolved a sophisticated sensory network called the DNA damage response (DDR) comprised of a large number of distinct protein complexes categorized as sensor, mediator, transducer and effector proteins that amplify the DNA damage signal and activate cell cycle checkpoint to initiate DNA repair or trigger apoptosis where the defect is beyond repair. This intricate signaling pathway is tightly regulated by …

Fluorinated N,N'-Diarylureas As Novel Therapeutic Agents Against Cancer Stem Cells, Dasha E. Kenlan, Piotr G. Rychahou, Vitaliy M. Sviripa, Heidi L. Weiss, Chunming Liu, David S. Watt, B. Mark Evers

Markey Cancer Center Faculty Publications

Colorectal cancer is the second-leading cause of cancer-related mortality in the United States. More than 50% of patients with colorectal cancer will develop local recurrence or distant organ metastasis. Cancer stem cells play a major role in the survival and metastasis of cancer cells. In this study, we examined the effects of novel AMP-activated protein kinase (AMPK) activating compounds on colorectal cancer metastatic and stem cell lines as potential candidates for chemotherapy. We found that activation of AMPK by all fluorinated N,N-diarylureas (FND) compounds at micromolar levels significantly inhibited the cell-cycle progression and subsequent cellular proliferation. In addition, we demonstrated …

Paracrine Regulation Of Melanocyte Genomic Stability: A Focus On Nucleotide Excision Repair, Stuart Gordon Jarrett, Katharine Marie Carter, John August D'Orazio

Markey Cancer Center Faculty Publications

UV radiation is a major environmental risk factor for the development of melanoma by causing DNA damage and mutations. Resistance to UV damage is largely determined by the capacity of melanocytes to respond to UV injury by repairing mutagenic photolesions. The nucleotide excision repair (NER) pathway is the major mechanism by which cells correct UV photodamage. This multistep process involves the basic steps of damage recognition, isolation, localized strand unwinding, assembly of a repair complex, excision of the damage‐containing strand 3′ and 5′ to the photolesion, synthesis of a sequence‐appropriate replacement strand, and finally ligation to restore continuity of genomic …

Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá

Biology Faculty Publications

Bullfrog invasion is a major conservation concern in South America, so there is an urgent need to detect and monitor its many invasion foci. Amphibian sampling methods commonly use calling display, specifically the nuptial calls of males. With the aim of obtaining the better day period to sample and monitor Lithobates catesbeianus presence, we recorded its calls at three ponds in two invaded localities in Uruguay (Aceguá, Cerro Largo, and San Carlos, Maldonado) during the reproductive season. Then, we studied the records, obtaining a subsample of calling intensity at the first 5 minutes for each hour. We detected that vocalization …

Parp Inhibitor Upregulates Pd-L1 Expression And Enhances Cancer-Associated Immunosuppression, Shiping Jiao

Dissertations and Theses (Open Access)

With recent approvals for therapeutic antibodies that block CTLA4, PD-1 and PD-L1, immune checkpoints have emerged as new targets in cancer therapy. In addition, there is accumulating evidence highlighting the role of cancer-associated immunity in patient response to cytotoxic anticancer agents. Inhibitors of poly (ADP-ribose) polymerase (PARP) have shown substantial cytotoxic effects against tumors with defects in DNA damage responses. However, whether a crosstalk between PARP inhibition and immune checkpoints exists remains unclear. Here, it has been shown that PARP inhibitors (PARPis) upregulate PD-L1 expression in multiple cancer cell lines, human xenograft tumors, and syngeneic mouse tumors. Mechanistically, PARPi inactivates …

Molecular Mechanisms Of Inward And Outward Budding From Multivesicular Endosomes, Monica Gireud Goss

Dissertations and Theses (Open Access)

Regulating the residence time of membrane proteins (e.g. transporters, ion channels, receptors) on the cell surface can modify their response to extracellular cues and allow for cellular adaptation to environmental conditions. The fate of membrane proteins that are internalized from the plasma membrane and arrive at the limiting membrane of the late endosome/multivesicular body (MVB) is dictated by whether they remain on the limiting membrane, bud into internal MVB vesicles, or bud outwardly from the membrane. The molecular details underlying the disposition of membrane proteins that transit this pathway and the mechanisms regulating these trafficking events are unclear. We established …

The Role Of The Diras Family Members In Regulating Ras Function, Cancer Growth And Autophagy, Margie Nicole Sutton

Dissertations and Theses (Open Access)

DIRAS3 is a maternally imprinted tumor suppressor gene that is downregulated by multiple mechanisms across several tumor types. When re-expressed, DIRAS3 decreases proliferation, inhibits motility, and induces autophagy and tumor dormancy. DIRAS3 encodes a 26 kDa small GTPase with 60% homology to Ras and Rap, differing from oncogenic Ras family members by a 34-amino acid N-terminal extension that is required for its tumor suppressive function in ovarian cancer. By assessing the structure-function relationship, I found that DIRAS3 inhibits Ras-induced transformation and is a natural antagonist of Ras/MAPK signaling. DIRAS3 binds directly to Ras and disrupts cluster formation inhibiting the activation …

Androgen Receptor And Prostate Cancer Cell Heterogeneity, Qu Deng

Dissertations and Theses (Open Access)

Androgen receptor (AR) plays an important role in prostate cancer (PCa) development and has been the main therapeutic target in advanced PCa. AR expression is heterogeneous in both primary PCa and castration resistant prostate cancer (CRPC). However, the functional significance of AR heterogeneity in regulating PCa biology and response to androgen/AR-targeted therapies remains unclear. The overarching hypothesis for my Ph.D is that AR heterogeneity contributes to PCa development, progression, and therapy resistance. A more specific postulate is that PCa cells expressing AR (i.e, AR⁺) and PCa cells expressing little AR (i.e, AR^-/lo) possess intrinsically distinct …

Proteomic Identification Of Histone Post-Translational Modifications Induced By Dna Double-Strand Breaks And Novel Proteins Involved In The Dna Damage Response, Pingping Wang

Dissertations and Theses (Open Access)

Inaccurate repair of DNA double-strand breaks (DSBs) can lead to DNA mutation and chromosome rearrangements, causing human diseases such as cancer. Although we know the basic mechanisms of DSB repair, the added complexities in the chromatin context are unclear. This is partially due to the lack of unbiased systems for identifying proteins and post-translational modifications (PTMs) involved in DSB repair. In this work, we established a novel method, termed DSB-ChAP-MS (Double Strand Break-Chromatin Affinity Purification with Mass Spectrometry), for the affinity purification of a sequence-specific single copy endogenous chromosomal locus containing a DSB, followed by the proteomic identification of enriched …

Non-Coding Rnas Identify The Intrinsic Molecular Subtypes Of Muscle-Invasive Bladder Cancer, Andrea E. Ochoa

Dissertations and Theses (Open Access)

NON-CODING RNAS IDENTIFY THE INTRINSIC MOLECULAR SUBTYPES OF MUSCLE-INVASIVE BLADDER CANCER

Andrea Elizabeth Ochoa, B.S.

Advisory Professors: David J. McConkey, Ph.D. and Joya Chandra, Ph.D.

There has been a recent explosion of genomics data in muscle-invasive bladder cancer (MIBC) to better understand the underlying biology of the disease that leads to the high amount of heterogeneity that is seen clinically. These studies have identified relatively stable intrinsic molecular subtypes of MIBC that show similarities to the basal and luminal subtypes of breast cancer. However, previous studies have primarily focused on protein-coding genes or DNA mutations/alterations.

There is emerging evidence implicating …

Investigation Of The Roles Of Asf1 And Caf-1-Mediated Chromatin Assembly In The Human Dna Damage Response, Ting-Hsiang Huang

Dissertations and Theses (Open Access)

The access-repair-restore model for the role of chromatin in DNA repair infers that chromatin is a mere obstacle to DNA repair. However, here we show that blocking chromatin assembly of newly-synthesized histones, via knockdown of the histone chaperones ASF1A, CAF-1 or a mutation that specifically prevents ASF1 binding to histones, hinders loading of Rad51 onto ssDNA during homologous recombination, as a consequence of reduced recruitment of the Rad51 loader MMS22L/TONSL to ssDNA, resulting in persistent RPA foci, extensive DNA end-resection, and persistent activation of the ATR-Chk1 pathway. By contrast, ASF1 and CAF-1 render the rapid inactivation of ATM Chk2 pathway …

Characterization Of The Ubiquitin Ligase, Ube4b, In Endocytic Trafficking, Natalie Sirisaengtaksin, Natalie Sirisaengtaksin

Dissertations and Theses (Open Access)

Endocytosis is a process by which cells internalize membrane proteins to remove them from the plasma membrane, allowing cells to regulate the cell surface expression of transmembrane proteins. In this manner, cellular responses to extracellular cues may be tuned by limiting the number of proteins available at the cell surface. One particular class of proteins, receptor tyrosine kinases (RTK), is internalized upon binding to extracellular ligands during their residence at the cell surface. The epidermal growth factor receptor (EGFR) is an RTK whose trafficking through the endocytic pathway through the cell is well-documented. Stimulation of EGFR with its cognate ligand, …

The Role Of Adenosine Signaling In Mature Erythrocytes And Erythroid Progenitors, Hong Liu

Dissertations and Theses (Open Access)

Adenosine is a ubiquitous nucleoside in almost all the cells throughout our bodies. It is highly induced particularly under hypoxia or energy depletion conditions. Adenosine functions as a critical ligand, after binding to membrane-associated adenosine receptors, adenosine initiates a downstream signaling cascade and subsequently contributes to functions of nervous system, immune response, vascular function and even metabolism.

Hypoxia is a condition with limited O₂ availability in the whole body or a region of the body. It is a major consequence of many respiratory and cardiovascular diseases, as well as for people living and working at high altitudes or other …

Understanding The Mechanism Of Genomic Instability During Replicative Aging In Budding Yeast, Sangita Pal

Dissertations and Theses (Open Access)

Aging brings a gradual decline in molecular fidelity and biological functionality, resulting in age related phenotypes and diseases. Despite continued efforts to uncover the conserved aging pathways among eukaryotes, exact molecular causes of aging are still poorly understood. One of the most important hallmarks of aging is increased genomic instability. However, there remains much ambiguity as to the cause. I am studying the replicative life span (RLS) of the genetically tractable model organism Saccharomyces cerevisiae, or budding yeast using the innovative “mother enrichment program” as the method to isolate unparalleled numbers of aged yeast cells to investigate the molecular changes …

Targeting Autophagy To Improve Efficacy Of Cdk4/6 Inhibition In Breast Cancer, Smruthi Vijayaraghavan

Dissertations and Theses (Open Access)

Deregulation of the cell cycle machinery is a hallmark of cancer, leading to aberrant proliferation and tumorigenesis. The crucial role of the CDK4/6-Cyclin D pathway has led to the development and FDA approval (palbociclib, ribociclib) of CDK4/6 inhibitors for the treatment of advanced estrogen receptor positive breast cancer. However, three major clinical challenges remain: i) adverse events leading to discontinuation of therapy and ii) lack of reliable biomarkers to identify responsive patients and iii) acquired resistance to CDK4/6 inhibitors. Previous in vitro studies have shown that palbociclib mediated CDK4/6 inhibition induces G1 arrest and senescence in ER+ breast cancer cells, …

Stromal Fibroblasts Restrain The Rate Of Colon Cancer Progression And Metastasis By Suppressing Regulatory T Cells And Colon Cancer Stem Cells, Changsoo Kwak

Dissertations and Theses (Open Access)

The initiation, progression, and metastasis of tumors involve not only cancer cells, but also the tumor microenvironment, which consists of immune or inflammatory cells, fibroblasts, endothelial cells, and extracellular matrix components (ECM). Fibroblasts are ubiquitous stromal cells that can influence other neighboring cell types through the secretion of chemokines, cytokines, ECM, ECM remodeling enzymes, and other metabolites. Myofibroblasts are a distinct subtype of fibroblasts characterized by expression α-smooth muscle actin (αSMA). These cells are a dominant component of the microenvironment, and a FSP1 and FAP could be a different clone of fibroblasts. Myofibroblasts also have been known to contribute to …

Annual Wormwood Leaf Inhibits The Adipogenesis Of 3t3-L1 And Obesity In High-Fat Diet-Induced Obese Rats, Y Song, S Lee, S Jang, T Kim, Hong-Duck Kim, S Kim, C Won, J Cho

NYMC Faculty Publications

Annual wormwood (AW) (Artemisia annua L.) has anti-malarial, anti-bacterial, anti-oxidant, anti-tumour, and anti-inflammatory activities. In the present study, we evaluated the effects of annual wormwood leaves (AWL) on adipocyte differentiation in 3T3-L1 cells and high-fat diet (HFD)-induced obese rats. 3T3-L1 adipocytes and HFD-induced obese rats were treated with AWL, and its effect on gene expression was analyzed using RT-PCR and Western blotting experiments. Treatment with AWL effectively prevented triglyceride accumulation during adipogenesis in a dose-dependent manner. Consistently, AWL suppressed the differentiation of 3T3-L1 preadipocytes into adipocytes through the downregulation of dexamethasone, 3-isobutyl-1- methylxanthine, and insulin (DMI)-induced serine/threonine kinase protein kinase …

Using Rb-Tnseq To Analyze Natural Variation In Saccharomyces Cerevisiae, Syed Raza Mahmood

Graduate Theses and Dissertations

One of the main challenges in biology today is the characterization of millions of genes of unknown function being continuously identified in sequencing studies. Transposon mutagenesis is a technique that has been widely used for annotating gene function and has now been combined with next-generation sequencing (Tn-Seq) to assess mutant fitness on a genome wide basis. However, Tn-Seq approaches are often constrained by laborious library preparation protocols which limit the number of organisms or conditions that can be assessed. Random bar code transposon-site sequencing (RB-TnSeq), is a transposon sequencing technique that streamlines library preparation and increases the throughput of mutant …