Molecular Biology Commons^™

Repositioning Propranolol To Block Mitogenic Signaling In Breast Cancer, Alexa Noel Montoya

Open Access Theses & Dissertations

Breast cancer is the second most diagnosed cancer among women and is about 30% of all new cases of female cancers each year. It is projected that 1 in 8 every U.S. woman (about 13%) develop invasive breast cancer over the course of her lifetime. While advances in cancer research have made it possible to elucidate several breast cancer genomic subtypes, and develop new novel therapies, many of these agents are associated with significant toxicity, as well as high costs. A retrospective cross-sectional study of 404 breast cancer patients was performed to determine the effect of β-blocker usage on tumor …

Functional Characterization Of The Human And Murine Schlafen Family Group Iii, Carlos A. Valenzuela

Open Access Theses & Dissertations

The Schlafen (SLFN) family of proteins are known for being encoded by interferon stimulated genes. The family is divided into three groups (I, II, III), for which the largest in size belong to the subgroup III. In humans, group III has the most members (SLFN5, SLFN11, SLFN13 and SLFN14); there is no member of group I and only one member of group II (SLFN12). All human SLFNs belonging to group III have been reported to impair viral protein expression or infection across a variety of viruses. The antiviral function is mediated in SLFN11 and SLFN13 by their tRNase activity, and …

Functional Analysis Of The Gamma-Aminobutyric Acid Type A Receptor Subunit Alpha-1 (Gabra1) Gene During Zebrafish Development., Nayeli Gabriela Reyes-Nava

Open Access Theses & Dissertations

The GABRA1 gene encodes for the alpha-1 (α1) subunit of the Gamma-Aminobutyric acid type A receptor (GABAAR), which are the primary modulators of synaptic inhibition in the central nervous system (CNS). Alpha-1 subunits are essential for maintaining the normal function of native receptors and contribute to over 60% of all GABAARs in the CNS. Remarkably, a broad spectrum of neurodevelopmental and epilepsy-associated disorders have been linked with mutations in the GABRA1 gene. However, the developmental, behavioral, and molecular mechanisms underlying GABRA1-associated epileptic disorders remain to be fully understood. Hence, the overarching goal of this dissertation is to investigate the behavioral …

Exploring The Anticancer Mechanism Of Thienopyrazole Derivative Tpz-1 In Acute Myeloid Leukemia, Jessica Dyanne Hess

Open Access Theses & Dissertations

Anticancer drug discovery is a time and resource-consuming process for which exceedingly reliable and efficient modern approaches are needed. Phenotypic drug screenings can generate highly potent and innovative drug candidates; however, deconvolution of the drugâ??s target often presents significant barriers to drug development. To overcome this hurdle, we have originally combined in vitro and in silico analyses to uncover the molecular mechanism(s) driving the anticancer activity of the uniquely structured small molecule drug candidate, Tpz-1. Our study revealed that Tpz-1 is a multitargeted agent which induces the programmed death of HL-60 acute myeloid leukemia cells primarily through disruption of microtubule …

Regulation Of C-C Chemokine Receptor 7 (Ccr7) Ligand-Mediated Internalization And Chemotaxis By G Protein-Coupled Receptor Kinase Family 4 (Grk-4, 5, 6) In Human Pediatric T-Cell Acute Lymphoblastic Leukemia (T-All), Eduardo Elias Chaib

Open Access Theses & Dissertations

Background and Significance: The Hispanic population is disproportionally affected by T-ALL (T-cell acute lymphoblastic leukemia) when compared to other races in the US. C-C Chemokine Receptor 7 (CCR7) in T-ALL is used during disease progression, and may lead to migration of cancerous cells into the Central Nervous System (CNS) of patients. Goals and Objectives: This project aims to find relevant rates and risk factors for T-ALL for the Hispanic population in the US/Mexico border region. The other aim is to assess the effect of the G protein-coupled Receptor Kinase 4 (GRK-4) family proteins on migration and receptor internalization through CCR7 …

Lipid Rafts, Exosomal Vesicles And Anti-Giardial Therapies, Brian Ivan Grajeda

Open Access Theses & Dissertations

Giardia lamblia, a protozoan parasite, is a major cause of waterborne infection, worldwide. While the trophozoite form of this parasite induces pathological symptoms in the gut, the cyst forms transmit the infection via contaminated water. Since Giardia is a non-invasive parasite, the actual mechanism by which it causes infection remains elusive. We have previously reported that Giardia assembles cholesterol and GM1 glycolipid-enriched lipid rafts (LRs) that participate in encystation and cyst production. To further delineate the role of LRs in pathogenesis, we isolated LRs from Giardia and subjected them to proteomic analysis. Various cellular proteins including the virulent proteins—e.g., giardins, …

In Vitro Investigation Of Tumor Selective Piperidones As Therapeutic Agents Against Leukemia Cancer Cells, Lisett Contreras

Open Access Theses & Dissertations

Cancer is a continuous global health issue. It is the second leading cause of death behind heart disease. Disparities across the emergence of cancer and resulting fatalities raise the importance of researching the disease. Treatments are available for certain types of cancers. However, these are typically accompanied by residual problems including side effects and the possibility for relapse. Some treatments attack all cells, leading to unwarranted side effects that make the possibility of living a comfortable life nearly impossible. Other treatments are specific to certain genetic alterations, making them only useful for a small percentage of patients. Not one treatment …

In The Search For Novel Treatments For Chagas' Disease Using Cutting-Edge Imaging Technology, Karsten Dieter Amezcua Winter

Open Access Theses & Dissertations

Chagas disease (ChD) is caused by Trypanosoma cruzi (T. cruzi), an intracellular protozoan parasite. ChD has a global mortality of 15,000 annual deaths, and approximately, 8-10 million people are infected. There is growing concern in the United States as autochthonous cases of ChD have been reported in the southern region. The two available treatments are only partially effective and highly toxic. N-aroyl derivatives and α, β-unsaturated ketones have been previously tested against Leishmania, a closely related parasite, demonstrating selective toxicity towards the microorganism. The objective of this study is to evaluate a drug library consisting of 21 α, β-unsaturated ketones …

Pacific Black Duck Ecology And Habitat Assessment In Aunu'u, American Samoa, And Their Relationship To Other Mallard-Like Ducks Of Oceania, Greater Indonesia, And The Philippines, Marissa Kaminski

Open Access Theses & Dissertations

Determining a species’ ecological needs, assessing the quality of their habitat, and determining genetic differentiation and connectivity among populations is essential to their conservation. My dissertation focuses on obtaining such a holistic view for a population of Pacific Black Ducks recently established on the Island of Aunu’u, American Samoa. Specifically, I present the first evaluation of the ecology and habitat of a recently established population of Pacific Black Ducks on the Island of Aunu’u, American Samoa, in Chapter 1, while I assess the genetic connectivity and relationship of this population to other Mallard-like ducks found in Greater Indonesia, Oceania, and …

The Role Of Calcium Ions In Signaling And Regulation Of Efflux Pump Genes In Staphylococcus Aureus, Amy Rebecca Nava

Open Access Theses & Dissertations

Calcium ions (Ca2+) play an important role in eukaryote cell signaling and regulation of physiological functions. Although evidence of a similar role for Ca2+ in prokaryotes has been difficult to demonstrate, there is mounting evidence that Ca2+ acts as a cell regulator in bacteria. The purpose of this study was to investigate Ca2+ signaling and the effect of Ca2+ on gene expression of various multidrug resistant (MDR) efflux pumps and their regulator MgrA in Staphylococcus aureus and clinically isolated MRSA. We hypothesized that the presence of Ca2+ increased gene expression of multidrug resistance pumps, LmrS, NorA, and the regulator, MgrA. …

Molecular And Cellular Characterizations Of Glucosylceramide Transferase (Synthase) In Giardia Lamblia, Vanessa Enriquez

Open Access Theses & Dissertations

Giardiasis, caused by an intestinal protozoan, Giardia lamblia, is a major public health problem worldwide. Giardia infection is spread through the fecal-oral route via contaminated water and food. It is estimated that over 280 million people are infected with Giardia across the globe. Giardia is a non-invasive parasite and consists of a two-stage life cycle: trophozoites and cysts. Ingested cysts undergo excystation in the proximal small intestine, releasing two trophozoites (excyzoites). Upon reaching the distal small intestine and colonizing there, trophozoites transform into cysts by encystation. It has been reported earlier that the process of encystation induced the synThesis of …

A Genomic Approach To Assessing The Fkbp52-Regulated Androgen Receptor Cistrome And Transcriptome, Nina Raquelle Ortiz

Open Access Theses & Dissertations

Androgen receptor (AR)-regulated genes contribute to the initiation and progression of prostate cancer. Receptor signaling persists and plays a pivotal role in late-stages of the disease, for which there is currently no treatment. Thus, there is a need to understand the mechanisms regulating AR function as a means to identify drug targets for potential therapeutics. The FKBP52 cochaperone has emerged in recent years as a regulator of AR activity that is functionally linked in the AR signaling pathway. FKBP52 is a known positive regulator of AR and believed to interact with AR at its binding function 3 surface (BF3), a …

A Role For Mek3 In The Oncogenesis Of Acute Lymphocytic Leukemia: Inactivation Of Mapk P38 Promotes Cell Proliferation Through Enhanced Degradation Of Mutant Mek3, Yoshira Marie Ayala-Marin

Open Access Theses & Dissertations

In the United States, pediatric leukemia has the second-highest cancer mortality rate in Hispanic children, especially Acute Lymphocytic Leukemia (ALL). While treatment of ALL has improved overall the five-year survival rate of ~90 %, not everyone has benefited. Twenty percent of them will experience relapse, and from these, 30 - 50 % will die. Unfortunately, the cause behind these dreadful statistics is poorly understood due to the complex etiology of this disease. Thereby, it is essential to identify potential oncogenic proteins that promote ALL so that new strategies can be developed to diagnose and treat this cancer. Whole Exome Sequencing …

Steroid-Coa Ligases, Fadd17a1 And Fadd19a1, And Their Role In Cholesterol Side-Chain Degradation In Mycobacterium Tuberculosis, Johnathan Salim Abou-Fadel

Open Access Theses & Dissertations

Mycobacterium tuberculosis (Mtb) is a serious health issue arising from the increasing incidence of multi-drug resistant (MDR-TB) strains that are becoming more prevalent in high-risk countries, especially here in the Texas/Mexico border. Confirmed cases and outbreaks in schools and hospitals are more frequent in this region due to the high-volume pedestrian traffic between the two cities, and the lack of a modernized health system in Mexico. Identification of new Mtb metabolic pathways for development of novel antitubercular drugs is urgently needed. The goal of this current work investigates two Mtb fatty acyl-CoA ligase enzymes' (FadD17A1 and FadD19A1) to explore whether …

Environmental And Genetic Factors Affecting Antibiotic Resistance Of Extended Spectrum Î?-Lactamase Bacteria From The Rio Grande River In El Paso, Tx And Cd. Juarez, Mexico, Maria D. Fuentes

Open Access Theses & Dissertations

Background: The Rio Grande River provides a major source of potable and agricultural water for the population of the Texas/Mexico border region. Cattle farming and ranching are the most prevalent activities, which may contribute to the microbial burden of pharmaceuticals into our state's water resources. Antibiotics, presumably released into the environment by discharges originating from waste-water treatment plants, septic disposal systems, animal feeding operations and urban runoff have a definite impact on the ecosystem and may contribute to an increase in antibiotic resistance. We hypothesized that waters of the Rio Grande River contained Multi Drug Resistant Organisms (MDRO) and mobile …

Crispr/Cas9-Induced Genetic Disruption And Characterization Of Udp-Galactopyranose Mutase In Trypanosoma Cruzi, Claudia Manriquez

Open Access Theses & Dissertations

The protozoan parasite, Trypanosoma cruzi, is the causative agent of Chagas disease (ChD), or American trypanosomiasis, which affects 6-8 million people in Latin America. It is estimated that 2-3 million people will develop severe lifelong cardiac and/or digestive disorders. ChD has become a life threat not only to endemic regions but most recently also to nonendemic regions, including the United States, owing to extensive worldwide migration in recent years. The lack of a vaccine and the limited efficacy of the two drug treatments available make it urgent to develop novel therapies to treat such a threatening disease. UDP-Galactopyranose mutase (UGM) …

Characterizing Regulatory Factors Of The Sumoylation System, David Quintanar

Open Access Theses & Dissertations

The effects that influenzaâ??s seasonal epidemics have on human health and the global economy have been clearly noted; while they are indeed very impressive, the impact of influenza pandemics arguably surpass other known infectious agents. Influenza A virus attaches to, enters, and infect cells by releasing its segmented genome which localize to the nucleus then use the hostâ??s cellular machinery to replicate and create viral progeny. The virus is able to hijack transcriptional components as well as to interact with other known and unknown host proteins which ultimately allows for a balance between cell viability and viral propagation. One known …

A Requirement For Y841 In Jak3 Enzymatic Activity And Hematopoietic Cancers, George Steven Martinez

Open Access Theses & Dissertations

A medical need exists for successfully treating people afflicted with leukemia, especially those who develop drug resistant forms. Relapse leukemia cases are particularly high within Hispanic populations where this disease is among the most frequently occurring cancer. Fourteen somatic mutations have been reported in Janus tyrosine kinase 3 (Jak3), including M511I and A573V, from patients with various forms of leukemia. To monitor drug sensitivity, a model system was developed. Indeed, many of these mutations have been shown to possess transforming ability in cell lines such as the IL-3 dependent pro-B cell line Ba/F3. As such, Ba/F3 cells were transformed to …

Defining And Characterizing The Step In The Hiv-1 Viral Life Cycle Affected By Fullerene Derivatives, Zachary Sean Martinez

Open Access Theses & Dissertations

Fullerene derivatives, both C60 and C70, were synthesized and characterized to test their activity against HIV-1 infection. The derivatives tested have previously been reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase. It was found that viruses produced in the presence of low micromolar concentrations of most of these fullerene derivatives exhibit a reduction in viral infectivity greater than 99%. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. These compounds did not affect infectivity of mature virions, indicating no effect on the early steps of the …

Vascularization In Interconnected 3d Printed Ti-6al-4v Foams With Hydrogel Matrix For Biomedical Bone Replacement Implants, Victor Correa

Open Access Theses & Dissertations

Abstract:

Vascularization or angiogenesis on newly implanted metal orthopedic implants has remained a challenge in the field of tissue engineering. In this research, an interconnected foam structure of Ti-6Al-4V was micro-fabricated by Electron Beam Melting (EBM) technique. The foam in question has a density of 1.77g/cm3 with 60% porosity and a tensile strength of 18GPa. An Extracellular Matrix based hydrogel was added as an aqueous matrix to the foam in question. Hypoxia mimetic stress has been closely related to many wound healing biomedical applications as it increases survival and proliferation molecular signals. To that end, increased expression of Hypoxia-Inducible Factor-1α …

Label-Free Quantitative Proteomics Reveals A Novel Sgta/Peroxiredoxin I Complex That Regulates Androgen Receptor Activity, Yenni Alejandra Garcia

Open Access Theses & Dissertations

The dynamic Hsp70-90 chaperone machinery along with its cochaperone partners are well-characterized for their ability to fold, assemble, and regulate steroid hormone receptors (SHRs). Human small glutamine rich tetratricopeptide repeat (TPR) containing protein alpha (SGTA) is a recently identified protein that has a characteristic Hsp90-binding TPR domain and is a key participant in the androgen, glucocorticoid, and progesterone receptor signaling pathway. In addition, SGTA plays a role in cellular processes such as cell cycle progression and apoptosis. We have demonstrated that SGTA binds directly to both Hsp70 (kd = 6 μM) and Hsp90 (kd = 11 μM). In a cell-free …

Identification And Characterization Of Small Molecules Targeting Fkbp52 As A Novel Treatment For Prostate Cancer, Naihsuan C. Guy

Open Access Theses & Dissertations

Prostate cancer (PCa) is one of the most commonly diagnosed diseases and the second leading cause of cancer deaths among men worldwide. Its growth is dependent upon androgen receptor (AR) signaling and the mainstay for treatment is hormone-ablation therapy using antiandrogens and/or androgen-deprivation therapies (ADT). Treatment of PCa with antiandrogens and/or ADT are initially effective; they act to repress the AR by directly competing with androgens for the ligand binding domain (LBD) and prevent activation of the receptor resulting in tumor regression. Unfortunately, the resistance to these treatments invariably emerges and results in a much more aggressive form of tumor …

Comparative Proteomic Analysis Of Extracellular Vesicles From Prostate Cancer-Derived Cell Lines, Gloria Polanco

Open Access Theses & Dissertations

Prostate cancer (PCa) is the leading non-cutaneous malignancy and the second deadliest among American men. PCa mortality rates among African American men are much higher than any other ethnic group, and the same is true for men of African ancestry world-wide. There is also a lack of reliable diagnostic markers and effective treatment options. Extracellular vesicles (EVs) have been observed to play an important role in cancer processes such as promotion of tumor growth and metastasis. They are also a promising source of diagnostic markers. This study addresses these problems by studying the proteome of EVs derived from PCa cells …

Elucidating The Molecular Mechanism Of Action By Which Rs1-208b Induces Apoptosis In Hematological Cancers, Ruben Israel Calderon

Open Access Theses & Dissertations

The 26S proteasome has been successfully targeted to treat multiple myeloma. However, the effect can sometimes be reversed as cells acquire resistance to chemotherapy. Recently, combining proteasome inhibitors with indirect proteasome inhibitors has been proposed in order to delay and even reverse resistance. Small molecules derived from 4-piperidinone that maintain an unsaturated β-carbonyl group are thought to interact with the thiol group of catalytically active cysteine residues in deubiquitinases that associate with the 26S proteasome, effectively inhibiting the proteasome.

RS1-208b was selected following a high-throughput screening of a small library of 4-piperidinone derived curcumin structural analogs due to its selectivity …

Characterization Of The Nodamura Virus Rna Dependent Rna Polymerase And Formation Of Rna Replication Complexes In Mammalian Cells, Vincent Ulysses Gant

Open Access Theses & Dissertations

Positive-strand RNA viruses amplify their genomes in membrane-bound structures associated with intracellular membranes and organelles called replication complexes (RCs). Here, we begin to elucidate mechanisms of Nodamura virus (NoV; family Nodaviridae) RC assembly. The literature reports that NoV-infected muscle tissue exhibits mitochondrial aggregation and rearrangement of mitochondrial structure, leading to disorganization of the muscle fibrils. However, the molecular basis for this pathogenesis and the role of mitochondria in NoV infection remained unclear until now. We tested the hypoThesis that NoV establishes RCs in association with mitochondria in cultured mammalian cells at physiological temperature. We used immunofluorescence confocal microscopy and biochemical …

The Sumoylation Of The Non-Structural Protein 1 Of The Influenza A Virus Plays A Dual Role During Viral Infection, Jason Michael Chacon

Open Access Theses & Dissertations

The potential for a highly pathogenic influenza pandemic remains a concern for global health. The ability of the influenza virus to undergo antigenic shift and genetic drift give circulating strains of influenza the high probability of developing resistance to current antiviral therapies. Emerging strains of higher virulence, to which the infected person has not had any previous exposure to viral antigens, pose a greater threat of serious illness and death. Currently, there is no antiviral therapy that is effective against all strains of influenza, emphasizing the need to develop new strategies that target cellular systems required for viral replication to …

Sumoylation Affects Ns1'S Ability To Neutralize The Interferon Response, Jeanette Cecilia Gonzalez

Open Access Theses & Dissertations

It is of huge concern the possibility that at some point in the future we may face a new pandemic involving a highly pathogenic virus due to our current preventive and treatment options to fight this viral disease. The main reason for such limitations is the ability of the virus to go over constant antigenic shifts and drifts on its viral surface proteins HA and NA. The constant mutations that affect this virus cause the need of developing new vaccines for each influenza season. Periodically, the World Health Organization (WHO) reports that around 10% of the world population gets infected …

Global Sphingolipid Profile Of Giardia Lamblia During Stage Differentiation: The Influence Of Sphingomyelin Abundance On Viable Cyst Production, Trevor Thomas Duarte

Open Access Theses & Dissertations

Giardia lamblia is a protozoan parasite and a major cause of the waterborne-illness, giardiasis, worldwide. Giardiasis is endemic in developing countries and is a leading cause of non-viral- and non-bacterial-associated intestinal disorders. Acute symptoms of giardiasis include diarrhea, cramps, and malabsorption. The disease is often self-limiting, although the infection can result in long-term disorders such as chronic fatigue, stunted cognitive skills, and failure to thrive even after the parasite has been cleared.

This parasite exists in two morphologic forms--infective trophozoites and transmissible, water-resistant cyst, which is passed by the fecal-oral route and is likely to be spread by contaminated drinking …

A Comparative Approach To Assessing The Functional And Structural Characteristics Of Human Fkbp52 In The Regulation Of Steroid Hormone Receptor Signaling Pathway, Diondra Crystal Harris

Open Access Theses & Dissertations

The 52 kDa FK506 binding protein (h52) is a key positive regulator of Androgen Receptor (AR) in cellular and animal models and is an attractive target for the treatment of prostate cancer. Human FKBP52 is a known regulatory protein and co-chaperone that has been shown to play an important role in the regulation of the AR signaling pathway, and in the development of the male sexual phenotype. Cellular studies in mammalian and yeast cells reveal that FKBP52 is a positive regulator of AR, glucocorticoid receptor (GR), and progesterone receptor (PR), potentiating receptor-mediated gene expression up to 60-fold in some systems. …

Il-2rβ T450 Phosphorylation Is A Positive Regulator For Receptor Complex Stability And Activation Of Signaling Molecules, Blanca Estela Ruiz-Medina

Open Access Theses & Dissertations

Homeostasis of the immune system is required for proper defense against pathogenic insult. Cells of the innate and adaptive compartments provide a strictly regulated response to clear infections while allowing for self-tolerance. Dysregulation of the components of the immune system can lead to immunodeficiency, autoimmunity, and cancer. Key players of the immune response are T, B, and NK cells, which become strongly activated by IL2 through its receptor. The β subunit of the receptor becomes tyrosine, serine, and threonine phosphorylated upon induction with IL2. Phosphorylation of tyrosine residues has been extensively studied, however, the putative regulatory role of serine and …