Molecular Biology Commons^™

Histone Deacetylation As A Mechanism Of Ypel3 Down-Regulation In Er-A Positive Breast Cancer Cell Lines, Remah Ali

Browse all Theses and Dissertations

YPEL3 is a growth inhibitory gene that was established by our laboratory to trigger senescence in both primary and tumor cells. We recently reported YPEL3 to be directly repressed by estrogen in estrogen receptor-a positive (ER-a +ve) breast cancer cell lines. Here, we set out to determine whether the repression of YPEL3 involves histone deacetylation and, if so, elucidate the molecular mechanism of this activity. MCF-7, T-47D, and ZR-75.1 (all ER-a +ve) breast cancer cell lines were treated with varying doses of the global histone deacetylase inhibitors (HDACIs), trichostatin A (TSA) or suberoyl anilide hydroxamic acid (SAHA), for 24, 48 …

An Acid Catalyzed Reversible Ring-Opening/Ring-Closure Reaction Involving A Cyano-Rhodamine Spirolactam, H. Li, H. Guan, X. Duan, J. Hu, Guiren Wang, Qian Wang

Faculty Publications

Cyanamide was introduced into the rhodamine spirolactam framework to produce a colorless and non-fluorescent compound RBCN. It shows a reversible ring-opening/ring-closure process in response to the solution pH, which exhibits an “ON/OFF” switching in its fluorescence. Different from other rhodamine-type dyes, the ring-open form of RBCN is stable in protic solvents under neutral, near neutral and basic conditions, showing a pink color and very strong fluorescence. We also demonstrated the potential of RBCN in live cell imaging.

Expression Of An Epitope Tagged Tarp Effector In Chlamydia Trachomatis, Brenda Nguyen

HIM 1990-2015

Previous studies performed on Chlamydia trachomatis have demonstrated how these obligate intracellular microbes invade host cells through the utilization of secreted effector proteins. One secreted effector called Tarp (translocated actin recruiting protein) is implicated in cytoskeleton rearrangements that promote bacterial entry into the host cell. The focus of our study is to create a plasmid that carries the tarP gene that when transcribed and translated from within Chlamydia trachomatis will generate a c-Myc epitope tagged Tarp. The tag will be used in future studies to track the progression of the protein through the infectious process and will allow us to …

Development Of An Alkaline Phosphatase Reporter System For Use In The Lyme Disease Spirochete Borrelia Burgdorferi, Selina Sutchu

HIM 1990-2015

The use of the periplasmic alkaline phosphatase (PhoA) reporter protein from E. coli has been critical for definition of the topology of transmembrane proteins of multiple bacterial species. This report demonstrates development of a PhoA reporter system in B. burgdorferi. Codon usage of the E. coli phoA in B. burgdorferi was analyzed and an optimized version of the gene was obtained. In order to assess the differential activity of the reporter system, two optimized PhoA-fusion construct using B. burgdorferi proteins were engineered: one using the periplasmic protein OppAIV and one using the cytoplasmic protein PncA. The activity of PhoA requires …

Understanding The Role Of Plasmodium Falciparum Vamp8 Snare Homologue, Katherine Ferreira

HIM 1990-2015

Malaria is one of the worlds most deadly infectious diseases and results in almost a million deaths each year, largely in children under the age of five in Sub-Saharan Africa. Outside Africa, malaria is responsible for a large number of cases in the Amazon rainforest of Brazil, Middle East, and in some areas of Asia [37]. According to the World Health Organization, there was an estimated 655, 000 deaths from malaria in 2012. Malaria is caused by a eukaryotic Apicomplexan parasite, Plasmodium, which has three distinct life cycles occurring in the midgut of the female Anopheles mosquito, the liver of …

Target Validation For Neurofibromatosis Type 2 Therapeutics., Alejandra Guinart

Electronic Theses and Dissertations

Neurofibromatosis type 2 (NF2) is a benign tumor disease of the nervous system. Development of bilateral vestibular schwannomas is characteristic of NF2; however patients frequently present schwannomas on other nerves, as well as meningiomas and ependymomas. Currently, there are no drug therapies for NF2. There is an urgent need for development of NF2 therapeutics and this dissertation presents two independent potential therapeutic targets. The disease is caused by mutations in the NF2 gene that encodes a tumor suppressor called merlin. Loss of merlin function is associated with increased activity of Rac and p21-activated kinases (PAK) and deregulation of cytoskeletal organization. …

Characterization Of Innate Immunity In The Female Reproductive Tract For The Prevention Of Hiv Acquisition, Colleen Eade

Electronic Theses and Dissertations

Human immunodeficiency virus (HIV) infects 30 million people worldwide. In sub-Saharan Africa, the region most affected by HIV, women comprise 60% of the infected population. Heterosexual transmission is a major mode of viral acquisition, mandating further research of the process and prevention of HIV acquisition via the female reproductive tract (FRT). The FRT is a dynamic environment, protected by host immune mechanisms and commensal microbes. The disruption of either of these elements can increase susceptibility to HIV. Accordingly, one common risk factor for HIV acquisition is the microbial shift condition known as bacterial vaginosis (BV), which is characterized by the …

Molecular Regulators Of Post-Golgi Vldl Transport Vesicle (Pg-Vtv) Biogenesis, Aladdin Riad

Electronic Theses and Dissertations

Amongst its numerous functions, the liver is responsible for the synthesis and secretion of very low-density lipoprotein (VLDL). VLDL particles play the important role of facilitating the transport of lipids within the aqueous environment of the plasma; yet high plasma concentrations of these particles result in the pathogenesis of atherosclerosis, while low VLDL secretion from the liver results in hepatic steatosis. VLDL synthesis in the hepatocyte is completed in the Golgi apparatus, which serves as the final site of VLDL maturation prior to its secretion to the bloodstream. The mechanism by which VLDL’s targeted transport to the plasma membrane is …

Identification Of Proteins Regulating Vldl Sorting Into The Vldl Transport Vesicle (Vtv) And Involved In The Biogenesis Of The Vtv, Samata Tiwari

Electronic Theses and Dissertations

Increased secretion of very low-density lipoprotein (VLDL), a triglyceride-rich lipoprotein, by the liver causes hypertriglyceridemia, which is a major risk factor for the development of atherosclerosis. The rate of VLDL-secretion from the liver is determined by its controlled transport from the endoplasmic reticulum (ER) to the Golgi. The ER-to-Golgi transport of newly synthesized VLDL is a complex multi-step process and is mediated by the VLDL transport vesicle (VTV). Once a nascent VLDL particle is synthesized in the lumen of the ER, it triggers the process of VTV-biogenesis and this process requires coat complex II (COPII) proteins that mediate the formation …

Role Of Host Immune Response And Bacterial Autolysin Atl In Human Nasal Colonization By Staphylococcus Aureus, Vanathy Paramanandam

Electronic Theses and Dissertations

Staphylococcus aureus (SA) is a major human pathogen that colonizes the anterior nares in 30% of the human population. Though nasal carriage of SA is a known risk factor for the subsequent spread of SA infections, the dynamics of SA nasal colonization is poorly understood. Our research focuses on understanding the host and bacterial factors that might contribute to the human nasal colonization by SA. In an attempt to elucidate the host response to SA, we performed an autologous human in vivo nasal colonization study, which showed decreased survival rates of SA in hosts who elicited a robust immune response. …

Expression Of Rna Nanoparticles Based On Bacteriophage Phi29 Prna In Escherichia Coli And Bacillus Subtilis, Le Zhang

Theses and Dissertations--Pharmacy

Currently, most of the RNAs used in lab research are prepared by in vitro transcription or chemical synthesis, which can be costly. In vivo expression in bacterial cells is another approach to RNA preparation that allows large scale production at a lower cost. However, there are some obstacles in bacterial expression, including RNA degradation in host cell, as well as RNA extraction and purification. tRNA and 5S RNA have been reported as scaffolds to circumvent the degradation problem. These scaffolds can not only make the RNA product survive in the cell but also increase the stability after extraction.

The packaging …

Amalgamation Of Nucleosides And Amino Acids In Antibiotic Biosynthesis, Sandra H. Barnard

Theses and Dissertations--Pharmacy

The rapid increase in antibiotic resistance demands the identification of novel antibiotics with novel targets. One potential antibacterial target is the biosynthesis of peptidoglycan cell wall, which is both ubiquitous and necessary for bacterial survival. Both the caprazamycin-related compounds A-90289 and muraminomicin, as well as the capuramycin-related compounds A-503083 and A-102395 are potent inhibitors of the translocase I enzyme, one of the key enzymes required for cell wall biosynthesis. The caprazamycin-related compounds contain a core nonproteinogen b-hydroxy-a-amino acid referred to as 5’-C-glycyluridine (GlyU). Residing within the biosynthetic gene clusters of the aforementioned compounds is a shared open reading …

Overexpression/Silencing Of Selected Soybean Genes Alters Resistance To Pathogens, Mohamed H. El-Habbak

Theses and Dissertations--Plant Pathology

Plant diseases remain a major obstruction to meeting the world’s increased demand for soybean oil and protein. Reducing the losses caused by diseases in order to improve crop production is a high priority for agricultural research. The need for novel strategies for plant disease control cannot be overstated. In the present study, selected defense-related genes were silenced and/or overexpressed in soybean using a virus-based vector and the resultant plants were tested for their responses to pathogens. The first part of the study focused on Rps1k (Resistance to Phytophthora sojae) gene. The two conserved domains encoding ‘P-Loop NTPase’ and ‘PLN03210’ …

Effect Of Hinge Region Phosphorylation On The Localization Of Thp1 In Tetrahymena Thermophila, Emily Bulley, Emily Wiley

Scripps Senior Theses

Within the cell nucleus, there are regions of highly condensed, transcriptionally silent chromatin called heterochromatin. Heterochromatin plays an important role in both chromosomal stability and gene regulation within the cell. Heterochromatin assembly is mediated by Heterochromatin Protein 1 (HP1) binding to epigenetically marked histone tails, most notably methylated H3K9. HP1 is post-translationally phosphorylated at serine and threonine residues, and this phosphorylation has been shown to increase HP1’s binding affinity for methylated H3K9 and heterochromatin formation. To study the effect of phosphorylation on heterochromatin assembly and HP1 localization within the nucleus, the unicellular protozoan Tetrahymena thermophila was used. Tetrahymena is an …

Engineering Novel Terpene Production Platforms In The Yeast Saccharomyces Cerevisiae, Xun Zhuang

Theses and Dissertations--Plant and Soil Sciences

The chemical diversity and biological activities of terpene and terpenoids have served in the development of new flavors, fragrances, medicines and pesticides. While terpenes are made predominantly by plants and microbes in small amounts and as components of complex mixtures, chemical synthesis of terpenes remains technically challenging, costly and inefficient. In this dissertation, methods to create new yeast lines possessing a dispensable mevalonate biosynthetic pathway wherein carbon flux can be diverted to build any chemical class of terpene product are described. The ability of this line to generate diterpenes was next investigated. Using a 5.5 L fed bath fermentation system, …

The Role Of Polyadenylation In Seed Germination, Liuyin Ma

Theses and Dissertations--Plant and Soil Sciences

Seed germination has many impacts on the uses of seeds, and is an important subject for study. Seed germination is regulated at both transcriptional and post-transcriptional levels. Therefore, it is important to study how polyadenylation regulates gene expression during seed germination. To this end, a modified Illumina GAIIx sequencing protocol (described in Chapter Two) was developed that allows deep coverage of poly(A) site position and distribution.

Alternative polyadenylation (APA) regulates gene expression by choosing one potential poly(A) site on a precursor RNA consequentially shortening/lengthening the mRNA relative to other possible sites. To further explore this phenomenon, genes affected by APA …

Novel Cis-Restricted Β-Lactam Combretastatin A-4 Analogues Display Anti-Vascular And Anti-Metastatic Properties In Vitro, Seema M. Nathwani, Lisa M. Greene, Linda Hughes, Miriam Carr, Niamh O'Boyle, Susan Mcdonnell, Mary J. Meegan, Daniela M. Zisterer

Articles

No abstract provided.

Regulation Of The Tumor Suppresser P53 And Survivin By Ras And Ral Gtpases:Implications For Malignant Transformation, Awet G. Tecleab

USF Tampa Graduate Theses and Dissertations

Abstract

Although the critical role of the small GTPases Ras and Ral in oncogenesis has been well documented, much remains to be investigated about the molecular mechanism by which these GTPases regulate malignant transformation. The work under this thesis made two major contributions to this field. The first is the discovery that K-Ras, RalA and/or RalB are required for the maintenance of the high levels of the anti-apoptotic protein survivin in some human cancer cells, and the second is the demonstration that down regulation of K-Ras, RalA and/or RalB, but not Raf-1 or Akt1/2, stabilizes the tumor suppressor p53 and …

Mass Spectrometry-Based Methods For The Detection And Characterization Of Protein-Tyrosine Nitration, Kent W. Seeley

USF Tampa Graduate Theses and Dissertations

Protein tyrosine nitration (PTN) is a posttranslational modification resulting from oxidative/nitrosative stress that has been implicated in a wide variety of disease states. Characterization of PTN is challenging due to several factors including its low abundance in a given proteome, preferential site modification, multiple target site proximity within unique peptide sequences, and analytical method and instrument limitations. Current analytical techniques are insufficiently sensitive to identify endogenous nitration sites without incorporation of either nitrotyrosine or target protein enrichment. However, enrichment proficiency can also be inadequate. Chemical derivatization of the nitro- moiety can be incomplete or result in undesirable byproduct formation, while …

Proteolytic Processing Of The Amyloid Precursor Protein During Apoptosis And Cell Cycle: Implications For Alzheimer's Disease, Tina N. Fiorelli

USF Tampa Graduate Theses and Dissertations

Alzheimer's disease is characterized by the presence of amyloid plaques, made up primarily of Aϐ peptides, and neurofibrillary tangles, containing hyperphosphorylated tau. Aϐ is generated by sequential proteolysis of the amyloid precursor protein (APP) by beta and gamma secretases. The leading hypothesis of Alzheimer's disease pathogenesis is the amyloid cascade hypothesis, which suggests that amyloid is central to the disease process. However, tau pathology correlates more closely with cognitive dysfunction and follows a predictable anatomical course through the brain. We hypothesize that if Aϐ is upstream of tau pathology and tau pathology follows this predictable course through the brain, Aϐ …