Molecular Biology Commons^™

The Role Of Med31 And Med12 In Directing Adipogenesis Of Human Adult-Derived Mesenchymal Stem Cells, Joseph Straub

Doctoral Dissertations

Selective gene expression is crucial in maintaining the self-renewing and multipotent properties of stem cells. Mediator is a large, evolutionarily conserved, multisubunit protein complex that modulates gene expression by relaying signals from cell type-specific transcription factors to RNA polymerase II. In humans, this complex consists of 30 subunits arranged in four modules: head, middle, tail, and kinase. In our introduction, we show the state of the field of Mediator study with a focus on the critical kinase module. In the following chapters, we used siRNA knockdowns to investigate the roles of the highly-conserved core subunit MED31 and the kinase module …

Molecular Characterization Of Galectin From Amblyomma Americanum In Context Of Α-Gal Syndrome, Sumar Beauti

Honors Theses

The lone star tick Amblyomma americanum is a vector of various disease-causing pathogens and tick-borne alpha-gal syndrome (AGS) with rapidly expanding populations in the south- and northeast regions of the United States. This study aimed to molecularly characterize galectin and determine its involvement in galactose-α-1,3-galactose (α-gal) synthesis, transport, reproductive fitness, and microbial homeostasis in this tick. The lone star tick galectin possesses two conserved carbohydrate recognition domains and shares homology with other Ixodid tick galectins. Time and tissue-dependent expression data shows that galectin is constantly expressed in salivary glands, midgut, and ovary tissues. An RNA interference approach was used to …

Investigating A Novel Function For Phosphoserine Aminotransferase 1 (Psat1) In Epidermal Growth Factor Receptor (Egfr)-Mediated Lung Tumorigenesis., Rumeysa Biyik-Sit

Electronic Theses and Dissertations

Phosphoserine aminotransferase 1 (PSAT1) catalyzes the second enzymatic step within the serine synthetic pathway (SSP) and its expression is elevated in numerous human cancers, including non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) mutant NSCLC is characterized by activating mutations within its tyrosine kinase domain and accounts for 17% of lung adenocarcinomas. Although elevated SSP activity has been observed in EGFR-mutant lung cancer cells, the involvement of PSAT1 in EGFR-mediated oncogenesis is still unclear. Here, we explore a putative non-canonical function for PSAT1 using biochemical approaches to elucidate unknown interacting proteins and genomic RNA-seq profiling to identify cellular …

The Biochemical Characterization Of Aza197 And A Ras Related Protein Cdc42, Alix Montoya-Beltran

Graduate Theses and Dissertations

Eukaryotic cells contain an extensive amount of GTP/GDP binding proteins. Proteins known as Ras GTPase primary function as a binary switch, where they cycle from an on and off state when GTP or GDP are bound, respectively. They are known to play a critical role in many cellular functions where a dysregulation could potentially lead to oncogenic behavior or other malignancies. In our laboratory, our focus is the study of a Ras related protein Cell division control 42 homolog (Cdc42) which belongs to the Rho subfamily. Cdc42 plays a critical role in many biological signaling processes; therefore, its uncontrol gene …

The Analysis Of Folate-Dependent Transcription Factor Zinc Finger Protein 410, Feifan Xu

Senior Honors Theses

A previous study that introduced dietary folate to mice in the form of folic acid to determine if gene activity would be altered based on this biological molecule demonstrated that mice without folic acid had cognition deficits, and this phenomenon was correlated with altered gene expression in their brains. The included bioinformatic analysis revealed two main transcription factors that bind to proteins in the nucleus, and one is known as the Zinc Finger Protein 410 (Zfp410). Due to the lack of literature explaining the function of this transcription factor, this project is intended to analyze Zfp410 in detail from scratch. …

Cyclophilin D Is A Sensor Of Nano-Pulse Stimulation, Brittney Ruedlinger, Bani Hani Maisoun, Lucas Potter, Nicola Lai, Stephen J. Beebe

The Graduate School Posters

Nano-Pulse Stimulation (NPS), a pulsed power-derived technology, stimulates structural and functional changes in plasma membranes and cellular organelles. NPS induces a Ca²⁺ influx and opening of the mitochondrial permeability transition pore (mPTP) that dissipates the mitochondrial membrane potential (ΔΨ_m) and, when sustained, induces regulated cell death. Here we show that in rat cardiomyoblasts (H9C2) cyclophilin D (CypD) is a mitochondrial sensor for NPS as defined by observations that loss of ΔΨ_m is Ca²⁺ and mitochondrial reactive oxygen species (mROS) dependent and cyclosporin A (CsA)-sensitive, which are diagnostic qualities for effects on CypD and the mPTP. …

Long-Term Impacts Of Acute Stressor Exposure On Locus Coeruleus Function And Anxiety-Like Behavior In Rats, Olga Borodovitsyna

Graduate School of Biomedical Sciences Theses and Dissertations

Stress is a physiological state characterized by behavioral arousal that occurs during exposure to harmful or threatening stimuli, and usually facilitates an adaptive behavioral response. The persistence of stress sometimes causes it to become maladaptive, potentially contributing to disease development, including physiological complications with altered neuroendocrine signaling and impaired function of organ systems, and psychological conditions including depression and anxiety. Anxiety disorders in particular are associated with a history of stress and are the most common class of mental disorders, with a lifetime prevalence of 33.7% in the general population. The locus coeruleus (LC) is a major node in the …

A High-Throughput Approach To Characterizing Arv1 On The Regulation Of Lipid Homeostasis Uncovers A Novel Interaction With Epidermal Growth Factor Receptor, Nicholas Anthony Wachowski

Graduate School of Biomedical Sciences Theses and Dissertations

Acyl-CoA cholesterol acyl transferase related enzyme-2 required for viability 1 (ARV1) was first recognized in Saccharomyces cerevisiae in a study done in 2000 by Tinkelenberg et al. In yeast, the deletion of ARV1 results in numerous defects including abnormal sterol trafficking [1], the reduction of sphingolipid metabolism [2], synthesis of glycosylphosphatidylinositol (GPI) anchor [3], ER stress [4], and hypersensitivity of fatty acids leading to lipoapoptosis [5]. Arv1 germline deletion in mice displayed a lean phenotype with increased energy [6]. In humans, ARV1 mutations lead to epileptic encephalopathy [7].

Non-alcoholic fatty liver disease (NAFLD) consists of simple steatosis to non-alcoholic steatohepatitis …

Toward The Discovery Of Biological Functions Associated With The Mechanosensor Mtl1p Of Saccharomyces Cerevisiae Via Integrative Multi-Omics Analysis, Nelson Martínez-Matías, Nataliya Chorna, Sahily González-Crespo, Lilliam Villanueva, Ingrid Montes-Rodríguez, Loyda M. Melendez-Aponte, Abiel Roche-Lima, Kelvin Carrasquillo-Carrión, Ednalise Santiago-Cartagena, Brian C. Rymond, Mohan Babu, Igor Stagljar, José R. Rodríguez-Medina

Biology Faculty Publications

Functional analysis of the Mtl1 protein in Saccharomyces cerevisiae has revealed that this transmembrane sensor endows yeast cells with resistance to oxidative stress through a signaling mechanism called the cell wall integrity pathway (CWI). We observed upregulation of multiple heat shock proteins (HSPs), proteins associated with the formation of stress granules, and the phosphatase subunit of trehalose 6-phosphate synthase which suggests that mtl1Δ strains undergo intrinsic activation of a non-lethal heat stress response. Furthermore, quantitative global proteomic analysis conducted on TMT-labeled proteins combined with metabolome analysis revealed that mtl1Δ strains exhibit decreased levels of metabolites of carboxylic acid metabolism, decreased …

Mitochondrial Transfer From Mesenchymal Stem Cells Improves Neuronal Metabolism After Oxidant Injury In Vitro: The Role Of Miro1, Nancy Tseng, Scott C Lambie, Christopher Q Huynh, Bridget Sanford, Manisha Patel, Paco S Herson, D Ryan Ormond

Faculty, Staff and Students Publications

Stroke-induced cerebral ischemia is a major cause of death and disability. The disruption of blood flow results in neuronal and glial cell death leading to brain injury. Reperfusion restores oxygen to the affected tissue, but can also cause damage through an enhanced oxidative stress and inflammatory response. This study examines mitochondrial transfer from MSC to neurons and the role it plays in neuronal preservation after oxidant injury. We observed the transfer of mitochondria from MSC to mouse neurons in vitro following hydrogen peroxide exposure. The observed transfer was dependent on cell-to-cell contact and led to increased neuronal survival and improved …

The Effect Of A Folate Free Diet On Tumor Burden And Chemotherapy Effectiveness, Kendall E. Stalls

Senior Theses

Our research is to understand the effect of the microbiota on colorectal cancer. Evidence has been shown that the microbiota is linked to the development and progression of colorectal cancer. The research focuses on how the gut microbiome influences the effectiveness of colorectal cancer treatments. Specifically, how the composition of the microbiota and the metabolites that it secretes changes the response to chemotherapy. We also research how tumor burden can be altered through changing the composition of the gut bacteria. Our experiments are performed on APC/Min+ mice, that have been genetically altered to have colon cancer. We conducted an experiment …

Combining Multicolor Fish With Fluorescence Lifetime Imaging For Chromosomal Identification And Chromosomal Sub Structure Investigation, Archana Bhartiya, Ian Robinson, Mohammed Yousuf, Stanley W. Botchway

Centre for Regenerative Medicine & Stem Cell Research

Understanding the structure of chromatin in chromosomes during normal and diseased state of cells is still one of the key challenges in structural biology. Using DAPI staining alone together with Fluorescence lifetime imaging (FLIM), the environment of chromatin in chromosomes can be explored. Fluorescence lifetime can be used to probe the environment of a fluorophore such as energy transfer, pH and viscosity. Multicolor FISH (M-FISH) is a technique that allows individual chromosome identification, classification as well as assessment of the entire genome. Here we describe a combined approach using DAPI as a DNA environment sensor together with FLIM and M-FISH …

Reducing Seed Coat Fiber Content And Pod Shatter, And Engineering Medium Chain Fatty Acids-Containing Oil, In The Oilseed Crop Pennycress ( Thlaspi Arvense L. ), Maliheh Esfahanian

Theses and Dissertations

The overall goal of this thesis was to genetically improve agronomic traits of pennycress (Thlaspi arvense L.; Field Pennycress) and demonstrate the production of value-added designer seed oils to domesticate pennycress and enable its establishment as a new winter annual oilseed/meal/cover crop to be grown in temperate regions of the world. In the U.S. Midwest, pennycress can be double cropped on existing farmland during the time between corn harvest and subsequent planting of soybeans the following spring. Pennycress has the potential to produce 2,000 lbs/acre seeds, which at 33% by weight oil content and 20% protein, would yield 85 gallons/acre …

Bone Microenvironmental Control Of Skeletal Malignancy, Chen Hao Lo

USF Tampa Graduate Theses and Dissertations

Bone is a common site of metastasis for many solid malignancies. Bone-metastatic cancers pose a significant clinical problem worldwide and is among the main causes for cancer patient morbidity and mortality. Patients with advanced bone-metastatic diseases often present with either osteolytic or osteogenic bone diseases as their cancers progress. These bone pathologies are products of the cancer co-opting the local bone remodeling stroma to yield important growth nutrients and factors. Unfortunately, skeletal metastases remain incurable and are fatal. Identifying and understanding the causal multicellular and molecular interactions underlying skeletal malignancies can yield crucial ideas for targeting and inhibiting disease progression. …

Development Of Endoplasmic Reticulum Targeted Probes And Red Fluorescent Probes For Detecting Zinc, Drew Maslar

Electronic Theses and Dissertations

Zinc (Zn²⁺) is the second most abundant transition metal in the body and is important in various biological functions. Fluorescent sensors based on circularly permuted fluorescent proteins (cpFPs) have been previously made to detect labile, or unbound, Zn²⁺ within the cytoplasm of cells. These sensors have proven invaluable for studying Zn²⁺, however, these sensors are limited to their use in the cytoplasm and by the fact that only green cpFP have been utilized to create fluorescent Zn²⁺ sensors. In this thesis, we use a combination of peptide targeting sequences, site-directed mutagenesis, and rational design …

Characterization Of The Whale Shark (Rhincodon Typus) Melanocortin-2 Receptor, Brianne Hoglin

Electronic Theses and Dissertations

Among bony vertebrates, the melanocortin-2 receptor ortholog is unique among the family of five melanocortin receptors on the basis that it is dependent on its accessory protein, MRAP1, for trafficking and activation, and is selective for activation by ACTH alone. Previous studies on the MC2R orthologs of select cartilaginous fish, the elephant shark (Callorhinchus milii) and the red stingray (Dasyatis akajei), revealed divergent traits in a less obligatory relationship on MRAP1 and its ability to be activated by ACTH or the MSH-sized peptides. However, observed traits were not consistent between these two cartilaginous fish species, posing …

Rab35 Centered Membrane Trafficking Pathway Directs Apical Constriction During Drosophila Gastrulation, Hui Miao

Electronic Theses and Dissertations

Force generation in epithelial tissues is often pulsatile, with actomyosin networks generating high-tension contractile forces at the cell cortex before cyclically disassembling. This pulsed nature of cytoskeletal forces implies that there must be cellular processes to extract unidirectional changes that drive processive transformations in cell shape. During Drosophila melanogastergastrulation, the invagination of the prospective mesoderm is driven by the pulsed constriction of apical surfaces. Here, we address the mechanisms by which the irreversibility of pulsed events is achieved while also permitting uniform epithelial behaviors to emerge. We use MSD-based analyses to identify contractile steps and find that when a …

Fxs-Causing Point Mutations In Fmrp Disrupt Neuronal Granule Formation And Function, Emily L. Starke

Electronic Theses and Dissertations

Fragile X Syndrome (FXS) is a neurodevelopmental disorder caused by the disruption of Fragile X Mental Retardation Protein (FMRP) function in neurons, affecting nearly 1 in 7,500 individuals. Although FXS typically occurs from a complete loss of FMRP expression due to a CGG trinucleotide expansion within the 5’UTR of the FMR1 gene, single nucleotide polymorphisms (SNPs) within the KH domains of FMRP have been shown to severely disrupt FMRP function. FMRP is an RNA-binding translation repressor that interacts with ~4% of the neuronal transcriptome. Many target mRNAs encode for proteins important for regulating synaptic processes and modulate synaptic plasticity. It …

Molecular Dynamics Of Bcs1l: A New Homology Model And The Structural Impact Of Pathogenic Mutations, Josh Deyoung, Sadie Heeringa, Rachael Baker, Amy Wilstermann

Summer Research

• Mutations to BCS1L can lead to one of three distinct rare diseases: Björnstad syndrome, BCS1L mitopathy, GRACILE syndrome
• These diseases cause a variety of symptoms in patients that range from mild (hearing loss and brittle hair) to severe and fatal (iron overload, failure to thrive, lactic acidosis, aminoaciduria, early death)

Tracking The Subcellular Localization Of Surface Proteins In Staphylococcus Aureus By Immunofluorescence Microscopy, Salvatore J. Scaffidi, Mac A. Shebes, Wenqi Yu

Molecular Biosciences Faculty Publications

Surface proteins of Staphylococcus aureus and other Gram-positive bacteria play essential roles in bacterial colonization and host-microbe interactions. Surface protein precursors containing a YSIRK/GXXS signal peptide are translocated across the septal membrane at mid-cell, anchored to the cell wall peptidoglycan at the cross-wall compartment, and presented on the new hemispheres of the daughter cells following cell division. After several generations of cell division, these surface proteins will eventually cover the entire cell surface. To understand how these proteins travel from the bacterial cytoplasm to the cell surface, we describe a series of immunofluorescence microscopy protocols designed to detect the stepwise …

Dcaf14 Promotes Stalled Fork Stability To Maintain Genome Integrity, Arik Townsend, Gabriella Lora, Justin Engel, Neysha Tirado-Class, Huzefa Dungrawala

Molecular Biosciences Faculty Publications

No abstract provided.

Exploring The Connection Between The Spontaneous Regression Seen In Neuroblastomas, Hypertumors, And Reactive Oxygen Species, Shahad Musa, Manitha Mulpuru

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Peto’s Paradox is defined as the lack of correlation between larger animals and cancer risk. Under the assumption that all cells have equal risk of becoming cancerous, larger animals should have greater rates of cancer. However, the inverse is true. Determining the cause of this variation may allow a supplemental approach to cancer treatment. A combination of two reasons may account for this correlation including hypertumors and metabolism. Hypertumors, or cheater cells, are hypothesized to suppress cancer growth through spontaneous autophagic degradation and overexpression of the RAS g-protein. Both of these characteristics are exhibited in Neuroblastomas. An anticancer drug used …

Leveraging Chemical And Computational Biology To Probe The Cellulose Synthase Complex, B. Kirtley Amos

Theses and Dissertations--Plant and Soil Sciences

Cellular expansion in plants is a complex process driven by the constraint of internal cellular turgor pressure by an expansible cell wall. The main structural element of the cell wall is cellulose. Cellulose is vital to plant fitness and the protein complex that creates it is an excellent target for small molecule inhibition to create herbicides. In the following thesis many small molecules (SMs) from a diverse library were screened in search of new cellulose biosynthesis inhibitors (CBI). Loss of cellular expansion was the primary phenotype used to search for putative CBIs. As such, this was approached in a forward …

The Effect Of Cxcl12 Ligand On Internalization And Dimerization Of Cxcr4 Receptors In Live Cells, Loga Iyer

Williams Honors College, Honors Research Projects

The primary objective of this project was to determine the effect of CXCL12 ligand binding on the CXCR4 receptor, specifically, how it would impact receptor internalization and dimerization. The CXCL12 ligand derives from the stromal cell-derived alpha family [8]. The CXCR4 receptors, known as C-X-C chemokine receptor type 4 play an essential role in controlling cell proliferation. When misregulated, these receptors can drive tumorigenesis and are thus important targets of cancer therapy. These G protein-coupled receptors stimulate a cascade of signaling pathways in specific tissues [1]. These pathways include the positive transcriptional control of CXCR4 via the Nuclear Respiratory Factor-1 …

Entry And Replication Of Negative-Strand Rna Viruses, Kerri Boggs

Theses and Dissertations--Molecular and Cellular Biochemistry

Hendra virus (HeV) and human metapneumovirus (HMPV) are negative-sense, singled-stranded RNA viruses. The paramyxovirus HeV is classified as a biosafety level 4 pathogen due to its high fatality rate and the lack of a human vaccine or antiviral treatment. HMPV is a widespread pneumovirus that causes respiratory tract infections which are particularly dangerous for young children, immunocompromised individuals, and the elderly. Like HeV, no vaccines or therapies are available to combat HMPV infections. These viruses fuse their lipid envelopes with a cell to initiate infection. Blocking cell entry is a promising approach for antiviral development, and many vaccines are designed …

Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla

Dissertations and Theses

Parasitoid wasps are effective biological control agents that have evolved intricate host immune suppression strategies to overcome host immune defenses. The most important anti-parasite defense mechanism is encapsulation, where the host’s blood cells surround the wasp egg. In the Drosophila/Leptopilina host-parasitoid system, extracellular vesicles (EVs) are oviposited along with the wasp egg. The EVs possess spikes and contain hundreds of proteins, some of which enable wasp eggs to escape encapsulation by changing the morphology and function of hemocytes, or killing them. Previous studies have identified an abundant surface/spike protein (SSp40) from Leptopilina heterotoma EVs. While p40, a predicted …

From Inner Segment To Outer Segment: Palmitoylation Of Photoreceptor Na+, K+-Atpase And The Importance Of Prcd In Photoreceptor Outer Segment Morphogenesis, Emily R. Sechrest

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptors are specialized neuroepithelial cells which are optimized for efficient capture of light and initiation of visual transduction. These cells have several compartments which are very important for proper visual function and segregation of cellular processes, including the outer segment (OS), inner segment (IS), nucleus, and synapse. The IS houses all of the cellular organelles and biosynthetic molecular machinery the cell requires and is the site of protein synthesis. The light-sensing OS is a highly modified, primary cilium, which contains many stacks of double membranous discs which house proteins required for formation and maintenance of OS structure, as well as …

A Mechanism Behind The Mechanotransduction Of Surface Characteristics In Osteoblasts, Otto J. Juhl Iv

Theses and Dissertations

Biomaterials for use in bone regeneration and healing range from metal and metal alloy implants to hydrogel-based solutions. These materials can be optimized to increase bone healing and integration by improving the mechanical and biological properties. Regardless of the material itself, the cell-substrate interaction is key to the success of the biomaterial once implanted. Substrate surface characteristics such as roughness, wettability, and particle density are well-known contributors to a substrate’s overall osteogenic potential, and therefore the substrate's overall success. Unfortunately, it is still unknown how these substrate surface characteristics are transduced into intracellular signals by cells, preventing specific tailoring of …

Investigation Of Multidrug Efflux Transporter Acrb In Escherichia Coli: Assembly, Degradation And Dynamics, Prasangi Irosha Rajapaksha

Theses and Dissertations--Chemistry

The Resistant Nodulation Division (RND) super family member, tripartite AcrA-AcrB-TolC efflux pump, is a major contributor in conferring multidrug-resistance in Escherichia coli. The structure of the pump complex, and drug translocation by functional rotation mechanism have been widely studied. Despite of all these data, the dynamics of the assembly process of the pump and AcrB during functional rotation in the process of drug efflux remains poorly understood. My thesis focuses on understanding the pump assembly process, dynamics of AcrB in functional rotation mechanism, and also investigate the mechanism of degradation of AcrB facilitated by a C-terminal ssrA tag.

In the …

Mechanisms By Which Mnte-2-Pyp Suppresses Prostate Cancer Cell Growth, Yuxiang Zhu

Theses & Dissertations

Prostate cancer patients are often treated with radiotherapy. MnTE-2-PyP, is a superoxide dismutase (SOD) mimic and a known radioprotector of normal tissues. Our recent work demonstrates that MnTE-2-PyP also inhibits prostate cancer progression with radiotherapy; however, the mechanisms remain unclear. In this thesis, we identified that MnTE-2-PyP-induced intracellular H2O2 levels are critical in inhibiting growth of prostate cancer cells. We found that MnTE-2-PyP induced protein oxidations in PC3 cells and one major group of oxidized protein targets were involved in energy metabolism. The oxidative phosphorylation rates were significantly enhanced in both PC3 and LNCaP cells with MnTE-2-PyP treatment, but mitochondrial …