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Insights Into Hepatic Alpha-Fetoprotein Gene Regulation During Liver Development And Disease, Erica Leigh Clinkenbeard

Theses and Dissertations--Microbiology, Immunology, and Molecular Genetics

The liver is an essential organ for cholesterol homeostasis. If this process becomes dysregulated, cardiovascular disease (CVD) develops. Zinc-fingers and homeoboxes 2 (Zhx2) as an important hepatic gene regulator and contributes to CVD. BALB/cJ mice, with mutant Zhx2 allele, have fewer atherosclerotic plaques compared to other strains on a high fat diet. In my dissertation, I focused on the liver phenotype in BALB/cJ mice on a high-fat diet and found increased liver damage compared to wild-type Zhx2 mice. These data indicates that reduced Zhx2 in the liver leads to CVD resistance, but increases liver damage. Therefore, Zhx2 has an important …

Genetic And Biochemical Studies Of Human Apobec Family Of Proteins, Priyanga Wijesinghe

Wayne State University Dissertations

The AID/APOBEC family of proteins in higher vertebrates converts cytosines in DNA or RNA into uracil. These proteins have essential roles in either innate immunity or adaptive immunity. Recently, AID has also been implicated in DNA demethylation in the context of early embryogenesis in mammals. This is partly based on the reported ability of AID to deaminate 5-methyl cytosine to thymine (5mC to T). I reexamined this proposed new role of AID (5mC deamination) with two members of the APOBEC family in a novel Escherichia coli based genetic system. My results confirmed that while all three enzymes are strong cytosine …

Manipulation Of Host Signal Transduction Pathways And Cytoskeleton Functions By Invasive Bacterium Listeria Monocytogenes And Chlamydia Trachomatis, Shahanawaz Jiwani

Electronic Theses and Dissertations

Infectious disease remains one of the leading causes of morbidity and mortality worldwide. Many bacteria that cause disease have the capacity to enter into eukaryotic cells such as epithelial cells and tissue macrophages. Gaining access into the intracellular environment is one of the most critical steps in their survival and/or in pathogenesis. The entry mechanisms employed by these organisms vary considerably, but most mechanisms involve sabotaging and manipulating host cell functions. Invasion of epithelial cells involves triggering host signal transduction mechanisms to induce cytoskeleton rearrangement, thereby facilitating bacterial uptake. My work focuses on understanding the molecular mechanisms employed by bacterial …

Lipase-Kinase Associations Involving Pld2, Jak3 And Fes That Underlie Cancer Cell Proliferation And Invasion, Qing Ye

Browse all Theses and Dissertations

Phospholipase D (PLD) is an enzyme that breaks down phospholipids in the cell membrane. It has been suggested that PLD may play a role during cell proliferation and cell invasion of cancer cells. The objective of this thesis was to define new molecular signaling pathways in which PLD2 might be involved in terms of cell proliferation (first part) and cell invasion (second part). To this, I compared molecular and biochemical aspects between untransformed cell lines with highly invasive, transformed breast cancer cells. In the first part, I investigated the interaction of two tyrosine kinases with PLD2 and the effect of …

Dna Repair Fidelity And Cancer : Structural And Kinetic Insights From Dna Polymerase Beta Mutator Variants, Chelsea Lynne Gridley

Legacy Theses & Dissertations (2009 - 2024)

DNA polymerases are essential for genome replication and DNA repair in all living organisms. Precise DNA replication is critical for the preservation of genomic stability. Any insult, endogenous/exogenous, to cellular DNA requires properly functioning repair polymerases. In eukaryotes, DNA polymerase beta, a small enzyme (39 kDa), plays an important role in DNA repair during the base excision repair pathway. Pol beta catalyzes the incorporation of nucleotides in small stretches (1-6 nucleotides) of damaged double-stranded DNA. Should gap-filling synthesis by pol beta be compromised, mutations in genomic DNA accumulate, which are frequently linked to human diseases, including cancers. For this reason, …

Inhibition Of Glutamate Receptors By Constructing Bipartite Rna Aptamers, Jeffrey Hebert

Legacy Theses & Dissertations (2009 - 2024)

The relationship of excessive activity of AMPA-type glutamate receptors, and cell death, has long provided researchers a means of investigating neurodegenerative disorders, such as Parkinson's Disease (PD) and amyotrophic lateral sclerosis (ALS). Inhibitors of AMPA receptor channels, including chemical and nucleic acid molecules such as RNA aptamers, have served as potential therapeutic agents and treatment of neurodegenerative disorders. In this study, building bipartite aptamers to enhance inhibitory potency, as compared with a monomeric aptamer of AMPA receptor, is described. An enhanced potency is due, at least in part; to the proximity effect in bipartite structures or binding of a monomeric …

Characterization Of The Calmodulin-Ryanodine Receptor Interaction By Cryo-Electron Microscopy, Xiaojun Huang

Legacy Theses & Dissertations (2009 - 2024)

Ryanodine receptor (RyR) is a key player in excitation-contraction coupling (E-C coupling). Calmodulin (CaM) is one of the important regulatory factors of RyR. Two mammalian RyR isoforms, RyR1 and RyR2, are highly enriched in skeletal and cardiac muscle, respectively. Apo-calmodulin weakly activates RyR1 but inhibits RyR2, whereas Ca2+-calmodulin inhibits both the isoforms. Previous cryo-electron microscopy studies showed distinctly different binding locations on RyR1 for the two states of calmodulin. However, recent studies employing fluorescence resonance energy transfer appeared to challenge these findings. In chapter 1, using cryo-electron microscopy, we have determined that a mutant calmodulin, which is incapable of binding …

The Role Of Chromatin And Cofactors In The Transcriptional Memory Effect Exerted In Saccharomyces Cerevisiae, Emily Leigh Paul

Legacy Theses & Dissertations (2009 - 2024)

Abf1 and Rap1 are functionally similar general regulatory factors (GRFs) found in Saccharomyces cerevisiae . Abf1, in its role as a transcriptional activator, exerts a memory effect on some genes under its control. This effect results in transcription levels remaining steady when Abf1 dissociates from its binding site in a conditional mutant. In contrast, Rap1 fails to elicit the same effect on its regulatory targets. Transcriptional memory effects have been observed in many fields of study, including immunology, cancer, and stem cells, and conservation of transcription machinery will allow studies in yeast to be applied to higher organisms.

Gld-1 Represses Its Puf Mrna Targets Prior To/At Initiation Of Translation In The C.Elegans Germline, Gautham Sarathy

Legacy Theses & Dissertations (2009 - 2024)

The C.elegans germline offers an ideal system to study posttranscriptional regulation of gene expression as it is a major mechanism through which the control over gene expression is achieved. GLD-1 (defective in GermLine Development) is a maxi-KH motif containing RNA binding protein that controls various aspects of germline development from decision over germcell proliferation vs. meiotic entry to the production of mature gametes suggesting that GLD-1 likely controls many mRNA targets.

The Role Of Ess1 In Survival, Morphogenetic Switching And Transcription In The Fungal Pathogen Candida Albicans, Dhanushki Poornima Samaranayake

Legacy Theses & Dissertations (2009 - 2024)

Candida albicans is a fungal pathogen that causes serious infections among immune-compromised patients and premature infants. C. albicans can become drug resistant, therefore, identifying new antifungal drug targets is an important goal. Here, we study a peptidyl-prolyl cis/trans isomerase called Ess1 as a potential drug target. Ess1 is conserved among pathogenic fungi, and therefore, potential inhibitors of Ess1 should display a broad spectrum of activity. We confirm that Ess1 is essential for growth in Candida albicans, but unlike the previously published find, deleting one copy of the C. albicans ESS1 gene did not affect morphogenetic switching. However, further reducing activity …

Modulation Of Anti-Tumor Immune Response By Tgf-Β-Inducible Early Gene 1 (Tieg1), Andi Cani

Wayne State University Theses

Cancer immunotherapy has had limited clinical efficacy partly because regulatory T cells (Treg) suppress the immune response to tumor-associated antigens. Inducible regulatory T cells (iTreg), which are converted from naïve CD4 T cells by TGF-β, an abundant cytokine in the tumor microenvironment, may contribute to this immune suppression. Induction of Foxp3 by TGF-β is mediated by the transcription factor TIEG1 and abrogation of this protein prevents Foxp3 expression. We are testing the hypothesis that blockade of TIEG1 to prevent iTreg conversion will enhance immune response in DNA vaccination to the tumor associated antigen Her-2. Wild type and TIEG1 knockout mice …

Investigation Of A 16s Rna Central Domain Pseudoknot, Jenna Marie Jasinski-Bolak

Wayne State University Theses

X-ray crystallography of the prokaryotic 30S ribosomal subunit revealed a myriad of complex RNA-RNA, RNA-protein, and protein-protein interactions. Among these are several phylogenetically conserved RNA pseudoknots. Pseudoknots are structurally and functionally diverse RNA secondary structures. They are generally formed by two short complimentary sequences separated by many bases of single stranded regions or loops. These relatively simple folds are often yield complex structures that are key components of functionally important conformational changes in RNA structure. One such pseudoknot is located in the central domain of the 16S rRNA.

The central domain pseudoknot is formed by Watson-Crick base pairing between G570-C866 …

Identifying Sm22 As A Key Player In Arterial Diseases, Jianbin Shen

Wayne State University Dissertations

Background : Expression of vascular smooth muscle cell (VSMC) cytoskeleton markers including SM22 is down-regulated in arterial diseases including atherosclerosis where inflammation and osteochondrogenesis are present. However, the role of this downregulation in arterial pathogenesis is unknown. Hypothesis : Downregulation of SM22 may actively contribute to arterial pathogenesis. Methods : Five Sm22 knockout (Sm22^-/-) mice and their wild type littermates were subjected to carotid artery denudation, an artery injury model. Analyses were conducted on carotid arteries 2 weeks after injury. Primary VSMCs were isolated from mouse aortas and investigated individually at passage 2 to 4. Sm22 knockdown was …

Identification Of Cellular Functions Of Cardiolipin As Physiological Modifiers Of Barth Syndrome, Amit Shridhar Joshi

Wayne State University Dissertations

Cardiolipin (CL) is an anionic phospholipid synthesized in the mitochondrial inner membrane. Perturbation of CL metabolism leads to Barth syndrome (BTHS), a life threatening genetic disorder. I utilized genetic, biochemical and cell biological approaches in yeast to elucidate the cellular functions of CL. Understanding the functions of CL is expected to shed light on the pathology and possible treatments for BTHS.

BTHS is caused by mutations in TAZ1, which encodes a CL remodeling enzyme called tafazzin. BTHS patients exhibit a wide range of clinical presentations, indicating that physiological modifiers influence the BTHS phenotype. A targeted synthetic lethality screen was performed …

Cloning Of The Gene, Purification As Recombinant Protein And Functional Characterization Of Leishmania Mexicana Cytochrome B5 Reductase, Ala Azhari

USF Tampa Graduate Theses and Dissertations

Leishmania are protozoan parasites that are transmitted by a sand fly vector. These parasites affect not only humans but also wild animals including domestic dogs and rodents, which form an additional challenge and public health problem to control the disease. Leishmaniasis is an important disease with worldwide distribution, including Saudi Arabia, the Middle East, and other tropical and subtropical areas around the world. Due to the expansion of irrigation and agricultural activities, more exposure to sand fly occurs, which leads to the expansion of leishmaniasis infections as newly emerging disease.

Emerging drug resistance in leishmaniasis is an additional problem, contributed …

A Novel Link Between Akt1 And Twist1 In Ovarian Tumor Cell Motility And Invasiveness, Nirav Shah

Electronic Theses and Dissertations

Ovarian cancer results in more deaths per year than any other cancer of the female reproductive system. The low survival rate is partly due to the lack of early detection and the susceptibility to relapse. The AKT serine threonine kinase plays a pivotal role in hallmark cellular processes for the progression of ovarian cancer, including tumor cell growth and migration. Therapeutic targeting of pan-AKT has been problematic, in part due to feedback mechanisms and crosstalk with other pathways. The hypothesis for this study is that AKT 1, -2 and -3 isoforms may have different roles and regulate cell processes in …

Study Of Microrna-34a Mediated Post Transcriptional Regulation Of Mdm4, Pooja P. Mandke

Browse all Theses and Dissertations

MDM4 is an important negative regulator of the tumor suppressor p53. In normal unstressed cells the activity of p53 is kept under control by MDM4 and its homologue MDM2. MDM4 is said to possess oncogenic potential based on the evidence of its overexpression in many cancers. Until recently it was believed MDM4 is constitutively transcribed; however a decrease in full length MDM4 in response to genotoxic stress was observed paving way for exploring the mechanism responsible for this.

It was observed miR-34a a member of the miR34 family which is a direct transcriptional targets of p53 could have a potential …

Determination Of An Interaction Between Nipped B-Like Protein And Mll, Adam Robert Marek

Master's Theses

The Mixed Lineage Leukemia (MLL) protein serves as a positive transcriptional regulator during hematopoietic and embryonic development. The MLL gene can undergo chromosomal translocations producing leukemia-causing fusions that retain the MLL amino-terminus, including the repression domain. A recent yeast two-hybrid screening used the MLL repression domain as bait and yielded nine positive clones of Nipped B-like (NIPBL).

NIPBL is a crucial member of the cohesin complex, which functions in the segregation of sister chromatids during cell division. However, recent evidence suggests the cohesin complex can also function as a transcriptional regulator.

In this study, we wanted to confirm this interaction …

Dubious Role Of Mycobacterium Paratuberculosis In Pathogenesis Of Type I Diabetes, Saisathya Thanigachalam

Electronic Theses and Dissertations

Background: Type 1 Diabetes mellitus (TIDM) is a chronic disorder in which the insulin producing beta cells are selectively self-destroyed. Although the etiology of the disease has not been determined, genetic dispositions such as SLC11A1 polymorphism in suffering patients have been reported. The role of pathogenic microorganisms such as Mycobacterium avium subspecies paratuberculosis (MAP) in TIDM has also been recently debated. MAP is already known to cause paratuberculosis in cattle and now it is a strong suspect of causing autoimmune diseases in humans such as Crohn’s disease, multiple sclerosis, autoimmune Thyroiditis, rheumatoid arthritis and autoimmune diabetes. We hypothesis that molecular …

Cerium Oxide Nanoparticles Act As A Unique Catalyst And Scavenge Nitric Oxide And Peroxynitrite And Decrease Rns In Vitro And In Vivo, Janet Dowding

Electronic Theses and Dissertations

Cerium oxide nanoparticles (CeO2 NPs)(nanoceria) have been shown to possess a substantial oxygen storage capacity via the interchangeable surface reduction and oxidation of cerium atoms, cycling between the Ce4+ and Ce3+ redox states. Reduction of Ce4+ to Ce3+ causes oxygen vacancies or defects on the surface of the crystalline lattice structure of the particles, generating a cage for redox reactions to occur. The study of the chemical and biological properties of CeO2 NPs has expanded recently, and the methods used to synthesize these materials are also quite diverse. This has led to a plethora of studies describing various preparations of …

The Effects Of Extended Access To Methamphetamine Self-Administration On Dopaminergic Markers In The Striatum, Joe Luevano

Open Access Theses & Dissertations

Methamphetamine (METH) abuse is a persistent problem in the U.S. and abroad. Escalation of METH use among independent users occurs for a variety of physiological and psychological reasons. Methamphetamine dependence may be attributed to the rewarding effect of this drug via the dopaminergic systems of the central nervous system (CNS). The presence of METH in the CNS increases synaptic release of dopamine. This increase in dopaminergic neurotransmission is thought to be directly attributed to the rewarding effects of METH. Following METH use, compensatory changes have been found to occur in the dopaminergic system during various periods of abstinence. It is …

Spe-7, A Novel Regulator Of Msp Assembly In C Elegans Spermatocytes, Kari Lynn Messina

Dissertations, Theses, and Masters Projects

No abstract provided.

Molecular Mechanisms Involved In Inflammatory Angiogenesis Induced By Monocyte Chemotactic Protein Induced Protein-1 (Mcpip1), Arpita Roy

Electronic Theses and Dissertations

Major diseases such as cardiovascular diseases, diabetes, obesity and tumor growth are known to involve inflammatory angiogenesis. MCP-induced protein 1 (MCPIP1) encoded by ZC3H12A gene, was reported to promote angiogenesis and is addressed in my dissertation as MCPIP. The mechanism/s involved in the angiogenic differentiation induced by MCPIP was however unknown. The aim of this study was to bridge this gap in our knowledge and delineate the molecular mechanisms and sequential processes involved in angiogenesis mediated via MCPIP. To determine if angiogenesis induced by inflammatory cytokines, TNF-, IL-1 and IL-8 is mediated via induction of MCPIP, knockdown of MCPIP by …

Light-Activated Binary Nucleotide Reagent For Inactivation Of Dna Polymerase, Evan M. Cornett

Electronic Theses and Dissertations

This work explores a binary reagent approach to increase the specificity of covalent inhibitors. In this approach, two ligand analogs equipped with inert pre-reactive groups specifically bind a target biopolymer. The binding event brings the pre-reactive groups in proximity with each other. The two groups react, generating active chemical intermediates that covalently modify and inactivate the target. In the present study we compare the new approach with the traditional single-component reagent strategy using DNA polymerase from bacteriophage T4 as a model target biopolymer. We report the design and synthesis of two analogs of deoxythymidine triphosphate, a natural DNA polymerase substrate. …

Signals Delivered By Interleukin-7 Regulate The Activities Of Bim And Jund In T Lymphocytes, Shannon Moore Ruppert

Electronic Theses and Dissertations

Interleukin-7 (IL-7) is an essential cytokine for lymphocyte growth that has the potential for promoting proliferation and survival. While the survival and proliferative functions of IL-7 are well established, the identities of IL-7 signaling components in pathways other than JAK/STAT, that accomplish these tasks remain poorly defined. To this end, we used IL-7 dependent T-cells to examine those components necessary for cell growth and survival. Our studies revealed two novel signal transducers of the IL-7 growth signal: BimL and JunD. IL-7 promoted the activity of JNK (Jun N-terminal Kinase), and that JNK, in turn, drove the expression of JunD, a …

A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel

CMC Senior Theses

The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …

A Study Of The Effects Of Inosine Incorporation Into Dna Due To Defects In Purine Biosynthesis In Escherichia Coli, Jonathan Spence Church

Legacy Theses & Dissertations (2009 - 2024)

Deamination of purine bases can result in the formation of xanthine and hypoxanthine which can be miscoding and mutagenic in DNA. There are several mechanisms for the introduction of deaminated bases into DNA including simple hydrolysis, nitrosative chemistry and through the action of deaminase enzymes. A fourth method was recently presented which describes how deaminated purines can be incorporated into DNA due to defects in purine biosynthesis. Using fluctuation analysis, spontaneous mutation rates were studied in bacterial mutants that were deficient in specific genes involved in purine biosynthesis and dNTP precursor pool maintenance, including purA (adenylosuccinate synthetase), guaA (GMP synthetase), …