Cell and Developmental Biology Commons^™

Microrna-Target Interactions In Embryonic Stem Cells, Shuang Wu

Graduate School of Biomedical Sciences Theses and Dissertations

Animal embryogenesis is a highly orchestrated process involving many geneexpression programs that determine specific fates of individual cells during development. Gene expression can be regulated at different stages such as at transcription initiation or mRNA stability, and microRNA-mediated gene regulation is a crucial pathway on the regulation of mRNA stability. microRNAs, or miRNAs, are small, conserved non-coding RNAs that negatively regulate gene expression post-transcriptionally. The mouse miR-290-295 cluster and its human homolog miR-371-373 are stem cell-specific miRNA clusters, and their expression can only be observed in early embryos, primordial germ cells, germ cell compartments of adult testis and embryonic stem …

Identification Of Collagen Iv Associated Proteins In Drsophila Using Genetics And Mass Spectrometry, Mayank S. Kapadia

Masters Theses & Specialist Projects

Metastatic cancer cells invade and spread to other locations by disrupting the basement membrane (BM). The membrane plays a major role during the normal development of an organism as well. In order to understand the invasion mechanism it is important to know about the interactions occurring between the proteins of the BM during normal development. This study concentrates on isolating and identifying the major factors associated with collagen IV, a major component of BM, during the third instar larval development of Drosophila. Western blot and mass spectrometry analysis revealed that collagen IV associates with various growth factors, signaling molecules, and …

Nano Clay-Enhanced Calcium Phosphate Cements And Hydrogels For Biomedical Applications, Udayabhanu Jammalamadaka

Doctoral Dissertations

Biomaterials are used as templates for drug delivery, scaffolds in tissue engineering, grafts in surgeries, and support for tissue regeneration. Novel biomaterial composites are needed to meet multifaceted requirements of compatibility, ease of fabrication and controlled drug delivery. Currently used biomaterials in orthopedics surgeries suffer limitations in toxicity and preventing infections. Polymethyl methacrylate (PMMA) used as bone cement suffers from limitations of thermal necrosis and monomer toxicity calls for development of better cementing biomaterials. A biodegradable/bioresorbable cement with good mechanical properties is needed to address this short coming. Metal implants used in fixing fractures or total joint replacement needs improvements …

Lof1 And Interacting Transcription Factors In Plant Development And Crop Yield, Zoe Yeoh, Elizabeth Luscher, Patricia Springer

Student Publications

Transcription factors (TFs) help ensure proper gene expression in developing tissues, and thus play a role in plant development and plant architecture. LATERAL ORGAN FUSION1, or LOF1, is a TF expressed in the organ boundaries of Arabidopsis thaliana. lof1 mutants have fused axillary branches and cauline leaves, which indicates importance in boundary development. Because transcription factors are known to act in complexes, we wanted to discover what other proteins interact with LOF1. We executed a yeast-2-hybrid (Y2H) screen that identified several TFs as potential interactors: WHIRLY 3 (WHY3), MYB DOMAIN PROTEIN32 (MYB32), HOMEOBOX-LEUCINE ZIPPER PROTEIN4 (HB4), and LIGHT RESPONSE BTB2 …

Selfish Mutations: The Genetic Basis Of The Paternal Age Effect, Eoin C. Whelan

Biological Sciences Theses & Dissertations

As the mean age of childrearing grows, the effect of parental age on genetic disease and child health becomes ever more important. A number of autosomal dominant disorders show a dramatic paternal age effect due to selfish mutations: substitutions that grant spermatogonial stem cells (SSCs) a selective advantage in the testes of the father but have a deleterious effect in offspring.

I present a mathematical model to analyse the normal function of the stem cell compartment, which provides a framework for SSC renewal and accommodates differences between animal systems. In order to model the SSC mutation accumulation, a Markov chain …

Determination Of Glut1 Oligomerization Parameters Using Bioluminescent Förster Resonance Energy Transfer, Brendan D. Looyenga, Calvin Vanopstall, Zion Lee, Jed Bell

University Faculty Publications and Creative Works

The facilitated glucose transporter GLUT1 (SLC2A1) is an important mediator of glucose homeostasis in humans. Though it is found in most cell types to some extent, the level of GLUT1 expression across different cell types can vary dramatically. Prior studies in erythrocytes - which express particularly high levels of GLUT1 - have suggested that GLUT1 is able to form tetrameric complexes with enhanced transport activity. Whether dynamic aggregation of GLUT1 also occurs in cell types with more modest expression of GLUT1, however, is unclear. To address this question, we developed a genetically encoded bioluminescent Förster resonance energy transfer (BRET) assay …

Respiratory Syncytial Virus-Infected Mesenchymal Stem Cells Regulate Immunity Via Interferon-Beta And Indoleamine-2,3-Dioxygenase, Michael B. Cheung

USF Tampa Graduate Theses and Dissertations

Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory tract infection in young children worldwide, accounting for an estimated 33.8 million cases of respiratory disease, over 3 million of which require hospitalization, and between 66,000 and 199,000 deaths in this susceptible population. Additionally, severe RSV infection early in life is associated with an increased risk of wheeze and other airway disorders later in life. Despite this, there is currently no vaccine or economically reasonable prophylactic regimen to prevent infection. While disease is typically more severe in infancy RSV can infect throughout the lifespan repeatedly as the …

Cell Cycle Arrest By Tgfß1 Is Dependent On The Inhibition Of Cmg Helicase Assembly And Activation, Brook Samuel Nepon-Sixt

USF Tampa Graduate Theses and Dissertations

Tumorigenesis is a multifaceted set of events consisting of the deregulation of several cell-autonomous and tissue microenvironmental processes that ultimately leads to the acquisition of malignant disease. Transforming growth factor beta (TGFß) and its family members are regulatory cytokines that function to ensure proper organismal development and the maintenance of homeostasis by controlling cellular differentiation, proliferation, adhesion, and survival, as well as by modulating components of the cellular microenvironment and immune system. The pleiotropic control by TGFß of these cell intrinsic and extrinsic factors is intimately linked to the prevention of tumor formation, the specifics of which are dependent on …

Anticancer Activities Of Resveratrol In Colorectal Cancer, Evelien Schaafsma, Tze-Chen Hsieh, Barbara B. Doonan, John T. Pinto, Joseph M. Wu

NYMC Faculty Publications

Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a dietary polyphenolic phytochemical that has demonstrated health benefits such as cardioprotection, the prevention of neurodegeneration and chemoprevention. Resveratrol has shown great potential in the prevention and treatment of carcinomas and clinical trials support resveratrol as anticancer compound in colorectal carcinoma. Colorectal cancer remains a major cause of cancer-related deaths for both men and women in industrialized countries. Because of this widespread prevalence, identifying major risk factors and initiating colorectal screening procedures provide the distinct advantage for recognizing early disease and addressing treatable forms of CRC. Epidemiological studies of fruit and vegetable consumption in relationship to developing …

Staphylococcus Aureus Coordinates Leukocidin Expression And Pathogenesis By Sensing Metabolic Fluxes Via Rpirc, Divya Balasubramanian, Elizabeth A Ohneck, Jessica Chapman, Andy Weiss, Min Kyung Kim, Tamara Reyes-Robles, Judy Zhong, Lindsey N. Shaw, Desmond S. Lun, Beatrix Ueberheide, Bo Shopsin, Victor J Torres

Molecular Biosciences Faculty Publications

Staphylococcus aureus is a formidable human pathogen that uses secreted cytolytic factors to injure immune cells and promote infection of its host. Of these proteins, the bicomponent family of pore-forming leukocidins play critical roles in S. aureus pathogenesis. The regulatory mechanisms governing the expression of these toxins are incompletely defined. In this work, we performed a screen to identify transcriptional regulators involved in leukocidin expression in S. aureus strain USA300. We discovered that a metabolic sensor-regulator, RpiRc, is a potent and selective repressor of two leukocidins, LukED and LukSF-PV. Whole-genome transcriptomics, S. aureus exoprotein proteomics, and metabolomic analyses revealed that …

Loss Of Cell Adhesion Increases Tumorigenic Potential Of Polarity Deficient Scribble Mutant Cells, Indrayani Waghmare, Madhuri Kango-Singh

Biology Faculty Publications

Epithelial polarity genes are important for maintaining tissue architecture, and regulating growth. The Drosophila neoplastic tumor suppressor gene scribble (scrib) belongs to the basolateral polarity complex. Loss of scrib results in disruption of its growth regulatory functions, and downregulation or mislocalization of Scrib is correlated to tumor growth. Somatic scribble mutant cells (scrib-) surrounded by wild-type cells undergo apoptosis, which can be prevented by introduction of secondary mutations that provide a growth advantage. Using genetic tools in Drosophila, we analyzed the phenotypic effects of loss of scrib in different growth promoting backgrounds. We investigated if a central …

Dynamic Surfaces For The Study Of Mesenchymal Stem Cell Growth Through Adhesion Regulation, Jemma N. Roberts, Jugal Kishore Sahoo, Laura E. Mcnamara, Karl V. Burgess, Jingli Yang, Enateri V. Alakpa, Hilary J. Anderson, Jake Hay, Lesley-Anne Turner, Stephen J. Yarwood, Mischa Zelzer, Richard O.C. Oreffo, Rein V. Ulijn, Matthew J. Dalby

Advanced Science Research Center

Out of their niche environment, adult stem cells, such as mesenchymal stem cells (MSCs), spontaneously differentiate. This makes both studying these important regenerative cells and growing large numbers of stem cells for clinical use challenging. Traditional cell culture techniques have fallen short of meeting this challenge, but materials science offers hope. In this study, we have used emerging rules of managing adhesion/ cytoskeletal balance to prolong MSC cultures by fabricating controllable nanoscale cell interfaces using immobilized peptides that may be enzymatically activated to change their function. The surfaces can be altered (activated) at will to tip adhesion/cytoskeletal balance and initiate …

Nfat5/Stat3 Interaction Mediates Synergism Of High Salt With Il-17 Towards Induction Of Vegf-A Expression In Breast Cancer Cells, Suneetha Amara, Dalal Alotaibi, Venkataswarup Tiriveedhi

Biology Faculty Research

Chronic inflammation has been considered an important player in cancer proliferation and progression. High salt (sodium chloride) levels have been considered a potent inducer of chronic inflammation. In the present study, the synergistic role of high salt with interleukin (IL)‑17 towards induction of the inflammatory and angiogenic stress factor vascular endothelial growth factor (VEGF)‑A was investigated. Stimulation of MCF-7 breast cancer cells with high salt (0.2 M NaCl) and sub‑minimal IL‑17 (1 ng/ml) enhanced the expression of VEGF-A (2.9 and 2.6-fold, respectively, P<0.05) compared with untreated cells. Furthermore, co‑treatment with both high salt and sub‑minimal IL‑17 led to a 5.9‑fold increase in VEGF‑A expression (P<0.01), thus suggesting a synergistic role of these factors. VEGF‑A promoter analysis and specific small interfering RNA knock‑down of transcription factors revealed that high salt induced VEGF‑A expression through nuclear factor of activated T‑cells (NFAT)5, while IL‑17 induced VEGF‑A expression via signal transducer and activator of transcription (STAT)3 signaling mechanisms. Treatment of normal human aortic endothelial cells with the supernatant of activated MCF‑7 cells enhanced cell migration and induced expression of migration‑specific factors, including vascular cell adhesion protein, β1 integrin and cluster of differentiation 31. These data suggest that high salt levels synergize with pro‑inflammatory IL‑17 to potentially induce cancer progression and metastasis through VEGF‑A expression. Therefore, low‑salt diet, anti‑NFAT5 and anti‑STAT3 therapies may provide novel avenues for enhanced efficiency of the current cancer therapy.

Intronic Cleavage And Polyadenylation Regulates Gene Expression During Dna Damage Response Through U1 Snrna, Emral Devany, Ji Yeon Park, Michael R. Murphy, George Zakusilo, Jorge Baquero, Xiaokan Zhang, Mainul Hoque, Bin Tian, Frida E. Kleiman

Publications and Research

The DNA damage response involves coordinated control of gene expression and DNA repair. Using deep sequencing, we found widespread changes of alternative cleavage and polyadenylation site usage on ultraviolet-treatment in mammalian cells. Alternative cleavage and polyadenylation regulation in the 3ʹ untranslated region is substantial, leading to both shortening and lengthening of 3ʹ untranslated regions of genes. Interestingly, a strong activation of intronic alternative cleavage and polyadenylation sites is detected, resulting in widespread expression of truncated transcripts. Intronic alternative cleavage and polyadenylation events are biased to the 5ʹ end of genes and affect gene groups with important functions in DNA damage …

Hexavalent Chromium Induces Malignant Transformation Of Human Lung Bronchial Epithelial Cells Via Ros-Dependent Activation Of Mir-21-Pdcd4 Signaling, Poyil Pratheeshkumar, Young-Ok Son, Sasidharan Padmaja Divya, Lilia Turcios, Ram Vinod Roy, John Andrew Hitron, Lei Wang, Donghern Kim, Jin Dai, Padmaja Asha, Zhuo Zhang, Xianglin Shi

Center for Research on Environmental Disease Faculty Publications

Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with an increased risk of lung cancer. However, the mechanisms underlying Cr(VI)-induced carcinogenesis remain unclear. MicroRNA-21 (miR-21) is a key regulator of oncogenic processes. Studies have shown that miR-21 exerts its oncogenic activity by targeting the tumor suppressor gene programmed cell death 4 (PDCD4). The present study examined the role of miR-21-PDCD4 signaling in Cr(VI)-induced cell transformation and tumorigenesis. Results showed that Cr(VI) induces ROS generation in human bronchial epithelial (BEAS-2B) cells. Chronic exposure to Cr(VI) is able to cause malignant transformation in BEAS-2B cells. Cr(VI) caused a significant increase of …