Molecular Biology Commons^™

The Effects Of Specialized Pro-Resolving Mediator Lipoxin A4 On Pseudomonas Aeruginosa Biofilms And Interactions With Monocytes, Julianne M. Thornton

Graduate School of Biomedical Sciences Theses and Dissertations

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen known as a major cause of hospital-acquired secondary infections, commonly causing chronic respiratory infections in immunocompromised individuals, especially those with cystic fibrosis, and often found in wound infections. P. aeruginosa uses the quorum sensing pathway to readily form protective biofilms, which reduce the efficacy of antibiotics and access by host immune cells to eradicate the pathogen. Specialized pro-resolving mediators (SPMs) are lipids endogenously produced by the host immune response to infection to aid in infection resolution. One SPM, Lipoxin A4 (LxA4), has been shown to be a robust quorum sensing inhibitor.

The …

Modeling The Tripartite Role Of Cyclin C In Cellular Stress Response Coordination, Steven J. Doyle

Graduate School of Biomedical Sciences Theses and Dissertations

For normal cellular function, exogenous signals must be interpreted and careful coordination must take place to ensure desired fates are achieved. Mitochondria are key regulatory nodes of cellular fate, undergoing fission/fusion cycles depending on the needs of the cell, and help mediate cell death fates. The CKM or Cdk8 kinase module, is composed of cyclin C (CC), Cdk8, Med12/12L, and Med13/13L. The CKM controls RNA polymerase II, acting as a regulator of stress-response and growth-control genes. Following stress, CC translocates to the mitochondria and interacts with both fission and iRCD apoptotic mediators. We hypothesize that CC represents a key mediator, …

Investigating The Antibacterial And Immunomodulatory Properties Of Lactobacillus Acidophilus Postbiotics, Rachael M. Wilson

Graduate School of Biomedical Sciences Theses and Dissertations

Probiotics are nonpathogenic microorganisms that have been extensively studied for their ability to prevent various infectious, gastrointestinal, and autoimmune diseases. The mechanisms underlying these probiotic effects have not been elucidated. However, we and other researchers have evidence suggesting that probiotic bacteria secrete metabolites that are antimicrobial and anti-inflammatory. As such, we developed a methodology to collect the secreted metabolites from a probiotic bacterium, Lactobacillus acidophilus, and tested this cell free filtrate (CFF) both in vitro and in vivo. Using this CFF, we have demonstrated that L. acidophilus secretes a molecule(s) that has specific bactericidal activity against the opportunistic pathogen, Pseudomonas …

Analysis Of Ssa4 Reporter Expression By Q-Pcr, Susveen Sharanshi, Rebecca Adams

[Archive] Belmont University Research Symposium (BURS)

The synthesis of genome-encoded proteins via mRNA translation is integral to cell survival. In eukaryotes, such as S. cerevisiae, the mRNA that is produced in the nucleus must be exported to the cytoplasm for translation to occur, and this process is highly regulated. Specifically, the export of mRNA occurs via travel through nuclear pore complexes (NPCs), which are selective doorways embedded in the nuclear envelope. During cellular stress, such as heat shock, the cell needs to regulate gene expression to permit survival, and mRNA export is one step at which this occurs. At these high temperatures, a cell’s proteins …

Med13 Degradation Defines A New Receptor-Mediated Autophagy Pathway Activated By Nutrient Deprivation, Sara E. Hanley

Graduate School of Biomedical Sciences Theses and Dissertations

Cells are exposed to an enormous amount of diverse extracellular cues but have a limited arsenal of weapons for protecting and maintaining homeostasis. To overcome these restrictions, nature has engineered proteins that have multiple functions. The pleiotropy of using one protein to carry out a variety of functions allows cells to rapidly execute tailored responses to a diverse set of signals. The Cdk8 kinase module (CKM) is a conserved detachable unit of the Mediator complex predominantly known for its role in transcriptional regulation. The CKM is composed of four proteins, the scaffolding proteins Med13 and Med12, as well as the …

Serving Justice Case By Case, Michael Becker

WRIT: Journal of First-Year Writing

Forensic Science is an integral part of serving justice in today's society, and majority of the world has little understanding of what forensics is. Read this article on forensic science and how it relates to writing in today's world.

In Vitro Characterization Of Fluorogenic Chemical Tools To Study Human Carboxylesterases (Cess), Taylor Parish Spidle

Undergraduate Honors Theses

Human carboxylesterases (CESs) are enzymes that are responsible for the metabolism of many important pharmaceuticals. Although CESs are key players in the hydrolysis of many ester-containing drugs, they remain understudied. Our group hypothesizes that this is primarily because there are few methods capable of reporting activity in live cells. Here, I report a new series of fluorogenic chemical tools to study the CES activity of one of the two major CESs in humans, CES1, in live cells. MCP-Me, MCP-Et, and MCP-iPr utilize the same carbonate group of a previously developed chemical tool in our group, FCP-1, and work to mimic …

A Kinome-Wide Crispr Screen Identifies Ck1Α As A Target To Overcome Enzalutamide Resistance Of Prostate Cancer, Jinghui Liu, Yue Zhao, Daheng He, Katelyn M. Jones, Shan Tang, Derek B. Allison, Yanquan Zhang, Jing Chen, Qiongsi Zhang, Xinyi Wang, Chaohao Li, Chi Wang, Lang Li, Xiaoqi Liu

Markey Cancer Center Faculty Publications

Enzalutamide (ENZA), a second-generation androgen receptor antagonist, has significantly increased progression-free and overall survival of patients with metastatic prostate cancer (PCa). However, resistance remains a prominent obstacle in treatment. Utilizing a kinome-wide CRISPR-Cas9 knockout screen, we identified casein kinase 1a (CK1a) as a therapeutic target to overcome ENZA resistance. Depletion or pharmacologic inhibition of CK1a enhanced ENZA efficacy in ENZA-resistant cells and patient-derived xenografts. Mechanistically, CK1a phosphorylates the serine residue S1270 and modulates the protein abundance of ataxia telangiectasia mutated (ATM), a primary initiator of DNA double-strand break (DSB)-response signaling, which is compromised in ENZA-resistant cells and patients. Inhibition of …

Identification Of A Nacc1-Regulated Gene Signature Implicated In The Features Of Triple-Negative Breast Cancer, Chrispus Ngule, Hami Hemati, Xingcong Ren, Oluwafunminiyi Obaleye, Amos O. Akinyemi, Felix Oyelami, Xiaofang Xiong, Jianxun Song, Xia Liu, Jin-Ming Yang

Markey Cancer Center Faculty Publications

Triple-negative breast cancer (TNBC), characterized by a deficiency in estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor2 (HER2), is among the most lethal subtypes of breast cancer (BC). Nevertheless, the molecular determinants that contribute to its malignant phenotypes such as tumor heterogeneity and therapy resistance, remain elusive. In this study, we sought to identify the stemness-associated genes involved in TNBC progression. Using bioinformatics approaches, we found 55 up- and 9 downregulated genes in TNBC. Out of the 55 upregulated genes, a 5 gene-signature (CDK1, EZH2, CCNB1, CCNA2, and AURKA) involved in cell regeneration was positively correlated …

In Situ Microwave Fixation Provides An Instantaneous Snapshot Of The Brain Metabolome, Jelena A. Juras, Madison B. Webb, Lyndsay E. A. Young, Kia H. Markussen, Tara R. Hawkinson, Michael D. Buoncristiani, Kayli E. Bolton, Peyton T. Coburn, Meredith I. Williams, Lisa P. Y. Sun, William C. Sanders, Ronald C. Bruntz, Lindsey R. Conroy, Chi Wang, Matthew S. Gentry, Bret N. Smith, Ramon C. Sun

Markey Cancer Center Faculty Publications

Brain glucose metabolism is highly heterogeneous among brain regions and continues postmortem. In particular, we demonstrate exhaustion of glycogen and glucose and an increase in lactate production during conventional rapid brain resection and preservation by liquid nitrogen. In contrast, we show that these post- mortem changes are not observed with simultaneous animal sacrifice and in situ fixation with focused, high- power microwave. We further employ microwave fixation to define brain glucose metabolism in the mouse model of streptozotocin-induced type 1 diabetes. Using both total pool and isotope tracing analyses, we identified global glucose hypometabolism in multiple brain regions, evidenced by …

Targeting Lncrna Ddit4-As1 Sensitizes Triple Negative Breast Cancer To Chemotherapy Via Suppressing Of Autophagy, Ting Jiang, Jiaojiao Zhu, Shilong Jiang, Zonglin Chen, Ping Xu, Rong Gong, Changxin Zhong, Yueying Cheng, Xinyuan Sun, Wenjun Yi, Jinming Yang, Wenhu Zhou, Yan Cheng

Markey Cancer Center Faculty Publications

In this study, it is found that the lncRNA, DNA damage inducible transcript 4 antisense RNA1 (DDIT4-AS1), is highly expressed in triple-negative breast cancer (TNBC) cell lines and tissues due to H3K27 acetylation in the promoter region, and promotes the proliferation, migration, and invasion of TNBC cells via activating autophagy. Mechanistically, it is shown that DDIT4-AS1 induces autophagy by stabilizing DDIT4 mRNA via recruiting the RNA binding protein AUF1 and promoting the interaction between DDIT4 mRNA and AUF1, thereby inhibiting mTOR signaling pathway. Furthermore, silencing of DDIT4-AS1 enhances the sensitivity of TNBC cells to chemotherapeutic agents such as paclitaxel both …

Lipid Nanoparticle-Mediated Mrna Delivery In Lung Fibrosis, Matteo Massaro, Suhong Wu, Gherardo Baudo, Haoran Liu, Scott Collum, Hyunho Lee, Cinzia Stigliano, Victor Segura-Ibarra, Harry Karmouty-Quintana, Elvin Blanco

Faculty, Staff and Student Publications

mRNA delivery enables the specific synthesis of proteins with therapeutic potential, representing a powerful strategy in diseases lacking efficacious pharmacotherapies. Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by excessive extracellular matrix (ECM) deposition and subsequent alveolar remodeling. Alveolar epithelial type 2 cells (AEC2) and fibroblasts represent important targets in IPF given their role in initiating and driving aberrant wound healing responses that lead to excessive ECM deposition. Our objective was to examine a lipid nanoparticle (LNP)-based mRNA construct as a viable strategy to target alveolar epithelial cells and fibroblasts in IPF. mRNA-containing LNPs measuring ∼34 nm had …

Characterization And Genomic Analysis Of Two Escherichia Coli O157:H7 Bacteriophages Isolated From Pigeons, Mohamad I. Alolama

Dissertations

Enterohemorrhagic Escherichia coli, also known as EHEC, is a subset of Shiga toxin-producing E. coli (STEC), and it has recently been identified as one of the principal foodborne pathogens. E. coli O157:H7 is the most important serotype of STEC for its role in causing foodborne illnesses. E. coli O157:H7 could cause various gastroenteritis symptoms such as diarrhea, hemolytic uremic syndrome, hemorrhagic colitis, and thrombotic thrombocytopenic purpura and may cause death. Elimination of E. coli O157:H7 during food processing and storage is a possible solution. Bacteriophages have a significant impact on bacterial populations in nature due to their ability to …

Toward The Yeast Surface Display Of Microviridin B, Jillian Leigh Stafford

Chemistry and Chemical Biology ETDs

Humans have turned to natural products for medicinal therapeutics for millennia. In recent years, the ribosomally synthesized and post-translationally modified peptide (RiPP) class of natural products have garnered a lot of attention due to their ability for heterologous expression, relative ease of mutation, and vast biological activates. Microviridins are a family of RiPPs that contain a tricyclic cage-like structure through the formation of two lactone rings and one lactam ring catalyzed by two ATP-grasp ligase family enzymes. Microviridins are potent inhibitors of serine proteases and mutational studies of a small number of residues indicates the potential of peptide engineering protease …

The Function Of Transport Protein Mfl1 In Arabidopsis Thaliana, Joseph Qian

LSU Master's Theses

Photosynthesis serves as the primary process for plants to synthesize ATP and sugar molecules, however, this reaction requires many cofactors such as heme, plastoquinone, and iron-sulfur clusters to assist in energy gathering and electron transfer steps. Many of these require trace metals, such as iron, to cross across the chloroplast membranes and be incorporated into proteins and other organic molecules to form useable cofactors. The light-independent reactions of photosynthesis are also inefficient, with up to 25% of the photosynthetic energy wasted to metabolize the toxic waste product glycolate. The cellular logistics of both photorespiration and iron transport have been studied, …

A Forward Genetic Screen Identifies Genes Involved In Gametocyte Development Of The Human Malaria Parasite Plasmodium Falciparum., Jyotsna Chawla

USF Tampa Graduate Theses and Dissertations

Transmission of the deadly malaria parasite Plasmodium falciparum from human to mosquito is achieved by specialized intraerythrocytic sexual forms called gametocytes. Circulating in the vertebrate host, relatively few intraerythrocytic gametocytes are picked up during a bloodmeal to continue sexual development in the mosquito vector. Human-to-vector transmission thus represents an infection bottleneck in the parasite's life cycle for therapeutic interventions to prevent malaria. Though the crucial regulatory mechanisms leading to gametocyte commitment have recently come to light, networks of genes that control sexual development remain to be elucidated. Here, we report a forward genetic approach to identify genes associated with gametocyte …

Synthesis, Characterization, And Cytotoxicity Studies Of A Copper(Ii) Complex With Vanillin 3-Ethyl-Thiosemcarbazone A Ligand, Novia Mann, Ifeoluwa Oyeyemi, Duaa R. Alajroush, Elizabeth A. Tonsel-White, Stephen J. Beebe, Alvin Holder

Undergraduate Research Symposium

Triple-negative breast cancer (TNBC) is one of the most aggressive and challenging breast cancer subtypes to treat, as these cancer cells lack three common receptors: estrogen, progesterone, and human epidermal growth factor receptor 2. The multiple oxidation states transition metals can occupy have made this narrowly explored group popular for anti-cancer research in recent decades. Furthermore, the success of cisplatin, which has platinum as a metal center, while being a cancer-fighting agent with serious side effects, has caused other metal centers to be investigated as possible alternatives as chemotherapeutic drugs. Copper, as a biologically essential metal, makes an attractive candidate …

Characterization Of Tick And Host-Associated Factors Linked To Induction Of Alpha-Gal Syndrome., Surendra Raj Sharma, Surendra Raj Sharma

Dissertations

Alpha-Gal Syndrome (AGS) is a delayed allergic reaction caused by specific IgE antibodies to the oligosaccharide galactose-α-1,3-galactose (α-gal) present in red meat. AGS is a growing concern globally, with over 34,000 confirmed cases in the United States alone. Studies have linked AGS to tick bites, which sensitizes hosts against α-gal antigens and elevates α-gal specific IgE. This dissertation investigates the role of tick and host-associated factors in AGS development. Microbiome analysis of Am. americanum ticks revealed a comprehensive core microbiome profile and showed that new Fransiella-like endosymbionts dominate and outcompete conventional tick Coxiella endosymbionts. Ticks subjected to tetracycline treatment showed …

The Molecular And Cellular Response To Acat1/Soat1 Inhibition, Taylor C. Harned

Dartmouth College Ph.D Dissertations

Cholesterol is an important component of all mammalian cell membranes. It governs the membrane’s physical properties and creates the membrane order and heterogeneity required for complex membrane-related processes. Tight regulation of cholesterol levels and distribution are necessary for maintaining proper cell health. Likewise, disruptions in cholesterol homeostasis have been implicated in a variety of diseases, including Alzheimer’s disease (AD). Our lab, and others, have demonstrated the benefits of blocking acyl-CoA:cholesterol acyltransferase1/sterol O:acyltransferase 1 (ACAT1/SOAT1) in AD models by genetic ablation or pharmacological inhibition. We understand that blocking ACAT1/SOAT1 activity reduces amyloid and tau pathology, and that this is, at least …

Anterior And Posterior Tongue Regions And Taste Papillae: Distinct Roles And Regulatory Mechanisms With An Emphasis On Hedgehog Signaling And Antagonism., Archana Kumari, Charlotte M. Mistretta

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Sensory receptors across the entire tongue are engaged during eating. However, the tongue has distinctive regions with taste (fungiform and circumvallate) and non-taste (filiform) organs that are composed of specialized epithelia, connective tissues, and innervation. The tissue regions and papillae are adapted in form and function for taste and somatosensation associated with eating. It follows that homeostasis and regeneration of distinctive papillae and taste buds with particular functional roles require tailored molecular pathways. Nonetheless, in the chemosensory field, generalizations are often made between mechanisms that regulate anterior tongue fungiform and posterior circumvallate taste papillae, without a clear distinction that highlights …