Biochemistry, Biophysics, and Structural Biology Commons^™

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Uncovering The Identity And Metabolism Of Bacterial Coa-Rna, Joseph R. Spangler

Dissertations

Coenzyme A is an indispensable molecule in all known life with roles in metabolism, gene regulation, and macromolecule synthesis. As CoA is derived from RNA itself, it’s incorporation into RNA by in vitro methods has proven useful in research probing the origin of life based on the RNA World theory. The discovery in contemporary bacteria of RNA modified with CoA, however, provided an unexpected twist to previously well-characterized bacterial systems. The identity of sequences associated with CoA-RNA has been elusive since their discovery in 2009 based on the difficulties in isolation while maintaining RNA quality. The aim of this study …

Phopsphorylation And Ubiquitin Modification At Dna Damage Sites In Response To Double-Strand Breaks, Atanu Paul

Dissertations and Theses (Open Access)

Genomes of all organisms are continuously damaged by numerous exogenous and endogenous sources leading to different kinds of DNA lesions, which if not repaired efficiently may trigger wide-scale genomic instability, a hallmark of cancer development. To overcome this, cells have evolved a sophisticated sensory network called the DNA damage response (DDR) comprised of a large number of distinct protein complexes categorized as sensor, mediator, transducer and effector proteins that amplify the DNA damage signal and activate cell cycle checkpoint to initiate DNA repair or trigger apoptosis where the defect is beyond repair. This intricate signaling pathway is tightly regulated by …

Non-Coding Rnas Identify The Intrinsic Molecular Subtypes Of Muscle-Invasive Bladder Cancer, Andrea E. Ochoa

Dissertations and Theses (Open Access)

NON-CODING RNAS IDENTIFY THE INTRINSIC MOLECULAR SUBTYPES OF MUSCLE-INVASIVE BLADDER CANCER

Andrea Elizabeth Ochoa, B.S.

Advisory Professors: David J. McConkey, Ph.D. and Joya Chandra, Ph.D.

There has been a recent explosion of genomics data in muscle-invasive bladder cancer (MIBC) to better understand the underlying biology of the disease that leads to the high amount of heterogeneity that is seen clinically. These studies have identified relatively stable intrinsic molecular subtypes of MIBC that show similarities to the basal and luminal subtypes of breast cancer. However, previous studies have primarily focused on protein-coding genes or DNA mutations/alterations.

There is emerging evidence implicating …

The Role Of Adenosine Signaling In Mature Erythrocytes And Erythroid Progenitors, Hong Liu

Dissertations and Theses (Open Access)

Adenosine is a ubiquitous nucleoside in almost all the cells throughout our bodies. It is highly induced particularly under hypoxia or energy depletion conditions. Adenosine functions as a critical ligand, after binding to membrane-associated adenosine receptors, adenosine initiates a downstream signaling cascade and subsequently contributes to functions of nervous system, immune response, vascular function and even metabolism.

Hypoxia is a condition with limited O₂ availability in the whole body or a region of the body. It is a major consequence of many respiratory and cardiovascular diseases, as well as for people living and working at high altitudes or other …

Understanding The Mechanism Of Genomic Instability During Replicative Aging In Budding Yeast, Sangita Pal

Dissertations and Theses (Open Access)

Aging brings a gradual decline in molecular fidelity and biological functionality, resulting in age related phenotypes and diseases. Despite continued efforts to uncover the conserved aging pathways among eukaryotes, exact molecular causes of aging are still poorly understood. One of the most important hallmarks of aging is increased genomic instability. However, there remains much ambiguity as to the cause. I am studying the replicative life span (RLS) of the genetically tractable model organism Saccharomyces cerevisiae, or budding yeast using the innovative “mother enrichment program” as the method to isolate unparalleled numbers of aged yeast cells to investigate the molecular changes …

Using Rb-Tnseq To Analyze Natural Variation In Saccharomyces Cerevisiae, Syed Raza Mahmood

Graduate Theses and Dissertations

One of the main challenges in biology today is the characterization of millions of genes of unknown function being continuously identified in sequencing studies. Transposon mutagenesis is a technique that has been widely used for annotating gene function and has now been combined with next-generation sequencing (Tn-Seq) to assess mutant fitness on a genome wide basis. However, Tn-Seq approaches are often constrained by laborious library preparation protocols which limit the number of organisms or conditions that can be assessed. Random bar code transposon-site sequencing (RB-TnSeq), is a transposon sequencing technique that streamlines library preparation and increases the throughput of mutant …

Thylakoid Protein Targeting/Insertion By A Signal Recognition Particle In Chloroplasts, Priyanka Sharma

Graduate Theses and Dissertations

Protein targeting is a fundamental cellular process that directs proteins from their site of synthesis to the site where they function. The signal recognition particle (SRP) dependent targeting pathway is conserved in both eukaryotes and prokaryotes where it co-translationally targets polypeptide chains emerging from ribosomes to the endoplasmic reticulum (eukaryotes) or cytoplasmic membrane (prokaryotes). A structurally unique form of SRP is found in chloroplasts where it functions to post-translationally bind and target a subset of integral thylakoid membrane proteins, the light harvesting chlorophyll binding proteins (LHCPs). Mature LHCPs bind chlorophyll a/b and function in photosynthetic light capture. Like many other …

Melatonin And Its Metabolites Protect Human Melanocytes Against Uvb-Induced Damage: Involvement Of Nrf2-Mediated Pathways, Zorica Janjetovic, Stuart G. Jarrett, Elizabeth F. Lee, Cory Duprey, Russel J. Reiter, Andrzej T. Slominski

Toxicology and Cancer Biology Faculty Publications

Ultraviolet light (UV) is an inducer of reactive oxygen species (ROS) as well as 6-4-photoproducts and cyclobutane pyrimidine dimers (CPD) in the skin, which further cause damage to the skin cells. Irradiation of cultured human melanocytes with UVB stimulated ROS production, which was reduced in cells treated with melatonin or its metabolites: 6-hydroxymelatonin (6-OHM), N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N-acetylserotonin (NAS), and 5-methoxytryptamine (5-MT). Melatonin and its derivatives also stimulated the expression of NRF2 (nuclear factor erythroid 2 [NF-E2]-related factor 2) and its target enzymes and proteins that play an important role in cell protection from different damaging factors including UVB. Silencing …

Uncovering Transcriptional Activators And Targets Of Hsf-1 In Caenorhabditis Elegans, Jessica Brunquell

USF Tampa Graduate Theses and Dissertations

In order to survive, cells must be able to cope with a variety of environmental stressors. The heat shock response (HSR) is a pro-survival mechanism employed by cells in response to protein denaturing stress, such as heat. Since its discovery in 1960, the heat shock response has been found to be regulated by the transcription factor heat shock factor 1 (HSF1). During periods of increased stress, HSF1 undergoes a multi-step process of activation that involves homotrimerization, DNA-binding, and post-translational regulatory modifications, all of which ultimately function to control the transcription of chaperone genes. These chaperone genes encode molecular chaperone proteins …

Inquiry Into Perilipin-5a Expression In Triacylglycerol Rich Vs Normal Fed Mouse Tissue, Kobi Agyepong

Undergraduate Honors Thesis Projects

The steep rise in both childhood and adult obesity over the past three decades has moved to the forefront of public consciousness in recent years. This development has generated a marked increase in general health awareness and lifestyle changes for a vast number of individuals, most notably in the form of increased physical activity and diet alterations. The latter point is especially salient in a biochemical context, because of the myriad factors that can result in “fat accumulation”. Chief among these factors is the Perilipin 5A gene, (known as PLIN5A) which encodes the protein Perilipin 5A of the Perilipin family …

Mass-Spectrometry Based Proteomics Of Age-Related Changes In Murine Microglia, Antwoine Flowers

USF Tampa Graduate Theses and Dissertations

The last century has seen a steady increase in the extension of the average lifespan. This has concomitantly produced higher incidences of age-related chronic degenerative diseases like Alzheimer’s and Parkinson’s diseases. Age is the single greatest risk factor for the development of not just these degenerative conditions but cancer as well. The aged niche undergoes a number of maladaptive changes that allow underlying conditions to present and progress. Exactly which changes, contribute to the progression of which disease is currently an area of intense study. However, these answers often present therapeutic targets for disease prevention. Age is characterized by a …

Pulmonary Surfactant Fortified With Cath-2 As A Novel Therapy For Bacterial Pneumonia, Brandon J. Baer

Western Research Forum

Background: Bacterial pneumonia is a leading cause of death worldwide, with high mortality rates persisting even after antibiotic treatment. Current treatments for pneumonia involve administration of antibiotics, however after the bacteria are killed they release toxic substances that induce inflammation and lung dysfunction. Host defense peptides represent a potential solution to this problem through their ability to down regulate inflammation. However, effective delivery to the lung is difficult because of the complex branching structure of the airways. My study addresses this delivery problem by using exogenous surfactant, a pulmonary delivery vehicle capable of improving spreading of these peptides throughout the …

Molecular Regulation Of Stem Cell Behavior During Tissue Repair And Cancer Formation, Nestor J. Oviedo

Science Seminar Series

Oviedo will be presenting his work on identifying the mechanisms of adult stem cell fate determination based on their topographical location in the adult body. Understanding stem cell fate determination is crucial because tissue repair and neoplastic growth are greater in anterior than in posterior regions of adult animals. Despite its critical implications for stem cell biology, carcinogenesis and regenerative medicine, this physiological phenomenon has remained overlooked. Recent findings from his group provide intriguing evidence implying DNA repair mechanisms and cellular signaling through post-translational modifications regulate stem cell fate decision depending on their topographical location in the adult body. We …

Foxo3 Increases Mir-34a To Cause Palmitate-Induced Cholangiocyte Lipoapoptosis, Sathish Kumar Natarajan, Bailey A. Stringham, Ashley M. Mohr, Cody J. Wehrkamp, Sizhao Lu, Mary Anne Phillippi, Duygu Dee Harrison-Findik, Justin L. Mott

School of Veterinary and Biomedical Sciences: Faculty Publications

Nonalcoholic steatohepatitis (NASH) patients have elevated plasma saturated free fatty acid levels. These toxic fatty acids can induce liver cell death and our recent results demonstrated that the biliary epithelium may be susceptible to lipotoxicity. Here, we explored the molecular mechanisms of cholangiocyte lipoapoptosis in cell culture and in an animal model of NASH. Treatment of cholangiocytes with palmitate (PA) showed increased caspase 3/7 activity and increased levels of cleaved poly (ADP-ribose) polymerase and cleaved caspase 3, demonstrating cholangiocyte lipoapoptosis. Interestingly, treatment with PA significantly increased the levels of microRNA miR-34a, a pro-apoptotic microRNA known to be elevated in NASH. …

The Mirnaome Of Catharanthus Roseus: Identification, Expression Analysis, And Potential Roles Of Micrornas In Regulation Of Terpenoid Indole Alkaloid Biosynthesis, Ethan M. Shen, Sanjay Kumar Singh, Jayadri S. Ghosh, Barunava Patra, Priyanka Paul, Ling Yuan, Sitakanta Pattanaik

Plant and Soil Sciences Faculty Publications

MicroRNAs (miRNAs) regulate numerous crucial biological processes in plants. However, information is limited on their involvement in the biosynthesis of specialized metabolites in plants, including Catharanthus roseus that produces a number of pharmaceutically valuable, bioactive terpenoid indole alkaloids (TIAs). Using small RNA-sequencing, we identified 181 conserved and 173 novel miRNAs (cro-miRNAs) in C. roseus seedlings. Genome-wide expression analysis revealed that a set of cro-miRNAs are differentially regulated in response to methyl jasmonate (MeJA). In silico target prediction identified 519 potential cro-miRNA targets that include several auxin response factors (ARFs). The presence of cleaved transcripts of miRNA-targeted ARFs in C. roseus …

Dual-Functional-Tag-Facilitated Protein Labeling And Immobilization, Xinyi Zhang, Wei Lu, Kevin Kwan, Dibakar Bhattacharyya, Yinan Wei

Chemistry Faculty Publications

An important strategy in the construction of biomimetic membranes and devices is to use natural proteins as the functional components for incorporation in a polymeric or nanocomposite matrix. Toward this goal, an important step is to immobilize proteins with high efficiency and precision without disrupting the protein function. Here, we developed a dual-functional tag containing histidine and the non-natural amino acid azidohomoalanine (AHA). AHA is metabolically incorporated into the protein, taking advantage of the Met-tRNA and Met-tRNA synthetase. Histidine in the tag can facilitate metal-affinity purification, whereas AHA can react with an alkyne-functionalized probe or surface via well-established click chemistry. …

Engineering Fret Biosensors For Microrna Presence/Absence Analysis, Nicholas E. Larkey, Sean M. Burrows

Biomedical Engineering Western Regional Conference

No abstract provided.

The Molecular Basis Of Talin2'S High Affinity Toward Β1-Integrin, Yaxia Yuan, Liqing Li, Yanyan Zhu, Lei Qi, Latifeh Azizi, Vesa P. Hytönen, Chang-Guo Zhan, Cai Huang

Molecular Modeling and Biopharmaceutical Center Faculty Publications

Talin interacts with β-integrin tails and actin to control integrin activation, thus regulating focal adhesion dynamics and cell migration. There are two talin genes, Tln1 and Tln2, which encode talin1 and talin2, and it is generally believed that talin2 functions redundantly with talin1. However, we show here that talin2 has a higher affinity to β1-integrin tails than talin1. Mutation of talin2 S339 to leucine, which can cause Fifth Finger Camptodactyly, a human genetic disease, completely disrupted its binding to β–integrin tails. Also, substitution of talin1 C336 with Ser enhanced the affinity of talin1, whereas substitution of talin2 S339 with …

Biophysical Tools To Study Cellular Mechanotransduction, Ismeel Muhamed, Farhan Chowdhury, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

The cell membrane is the interface that volumetrically isolates cellular components from the cell's environment. Proteins embedded within and on the membrane have varied biological functions: reception of external biochemical signals, as membrane channels, amplification and regulation of chemical signals through secondary messenger molecules, controlled exocytosis, endocytosis, phagocytosis, organized recruitment and sequestration of cytosolic complex proteins, cell division processes, organization of the cytoskeleton and more. The membrane's bioelectrical role is enabled by the physiologically controlled release and accumulation of electrochemical potential modulating molecules across the membrane through specialized ion channels (e.g., Na^⁺, Ca²⁺, K^⁺ channels). …

Transcriptional And Post-Transcriptional Regulation Of Histone Variant H2a.Z During Sea Urchin Development, Mihai Hajdu

Dissertations, Theses, and Capstone Projects

Histone variant H2A.Z promotes chromatin accessibility at transcriptional regulatory elements and is developmentally regulated in metazoans. We characterize the transcriptional and post-transcriptional regulation of H2A.Z in the purple sea urchin Strongylocentrotus purpuratus. H2A.Z depletion by antisense translation-blocking morpholino oligonucleotides during early development causes developmental collapse, in agreement with its previously demonstrated general role in transcriptional multipotency. During H2A.Z peak expression in 24-h embryos, endogenous H2A.Z 3’ UTR sequences stabilize GFP mRNAs relative to those with SV40 3’ UTR sequences, although the 3’UTR of H2A.Z does not determine the spatial distribution of H2A.Z transcripts during embryonic and postembryonic development. We …

Lipid Sensing By Mammalian Target Of Rapamycin, Deepak Menon

Dissertations, Theses, and Capstone Projects

Mammalian target of Rapamycin (mTOR) is a protein kinase that integrates nutrient and growth factor signals to promote cellular growth and proliferation. mTOR exists in two complexes - mTORC1 and mTORC2 that are distinguished by their binding partners and signaling inputs. mTORC1 is responsive to growth factors, amino acids and glucose and is associated with Raptor; whereas, mTORC2 is responsive primarily to growth factors and is associated with Rictor. Raptor and Rictor confer substrate specificity to mTORC1 and mTORC2 respectively. Phosphatidic acid (PA), a lipid second messenger and a central metabolite for membrane phospholipid biosynthesis, is required for the stability …

Evolution Of Complex Target Selex To Identify Aptamers Against Mammalian Cell-Surface Antigens, Prabodhika R. Mallikaratchy

Publications and Research

The demand has increased for sophisticated molecular tools with improved detection limits. Such molecules should be simple in structure, yet stable enough for clinical applications. Nucleic acid aptamers (NAAs) represent a class of molecules able to meet this demand. In particular, aptamers, a class of small nucleic acid ligands that are composed of single-stranded modified/unmodified RNA/DNA molecules, can be evolved from a complex library using Systematic Evolution of Ligands by EXponential enrichment (SELEX) against almost any molecule. Since its introduction in 1990, in stages, SELEX technology has itself undergone several modifications, improving selection and broadening the repertoire of targets. This …

Mechanisms Of Ikbke Activation In Cancer, Sridevi Challa

USF Tampa Graduate Theses and Dissertations

Cancer is the second leading cause of death in the USA and it is expected to surpass heart diseases making it important to understand the underlying mechanisms of cancer. The efforts to target single signaling molecule showed little success in increasing the patient survival and it can be due to increased compensation for cell survival by alternative pathway activations. Hence comprehensive understanding of the alternative signaling pathways may help us treat cancer better. Chronic inflammation is attributed to increased risk of cancer and emerging studies show the growing importance of both canonical and non-canonical IκB kinases such as IKKα, IKKβ, …

Survival Model Of Intrahepatic Cholangiocarcinoma; Sex As A Biological Variable, Mary A. Phillippi, Justin L. Mott, Cody J. Wehrkamp, Ying Xie, David Oupicky, Ashley M. Mohr, Bailey A. Stringham

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Oncogenic Nelfe Enhances Myc-Induced Hepatocellular Carcinogenesis, Hien Dang, Atsushi Takai, Marshonna Forgues, Yosawat Pomyen, Haiwei Mou, Wen Xue, Debashish Ray, Kevn Ha, Quiad Morris, Timothy Hughes, Xin Wei Wang

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Hepatocyte-Specific Deletion Of Tristetraprolin Family Of Rna Binding Proteins Result In The Development Of Hepatocellular Carcinomas, Sonika Patial

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Dense Core Vesicle Heterogeneity In Anterior Pituitary Cells, Kelly Sinak

Electronic Theses and Dissertations

Peptides, which are packaged in dense core vesicles, are an integral part of the function of the endocrine and neurological systems. The dense core vesicles function as an efficient form of peptide storage prior to regulated exocytosis. Two different dense core specific transmembrane proteins traffic different when comparted to retained prolactin cores, offering evidence of heterogeneity of vesicles within a single cell. By comparing synaptotagmin 1 and 7 distribution in male rat and lactating female lactotrophs, a distinct pattern emerges. Cells that retain prolactin cores after exocytosis correspond with those that contain synaptotagmin 1. This finding is a reversal for …

Development Of Cellular Assays To Monitor Enzymatic And Biological Activity Of Cd73: A Key Modulator Of Anti-Tumor Immune Response, Alexandra Fanuka

Graduate School of Biomedical Sciences Theses and Dissertations

Ecto-5’-nucleotidase, known as CD73, is an extracellular enzyme that converts adenosine monophosphate (AMP) to adenosine and has recently been identified as a potential drug target for cancer immunotherapy. Its immunosuppressive effects, mediated by the activity of adenosine, are associated with higher rates of tumor invasion and metastasis, as well as poorer prognoses overall in many cancer types. CD73 is often co-expressed with ectonucleoside triphosphate diphosphohydrolase-1 (CD39), which catalyzes the conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP), and ADP to AMP on the surface of tumor cells. Dual expression further propagates immunosuppressive effects of adenosine in the tumor microenvironment. …

Probing For Binding Regions Of The Ftsz Protein Surface Through Site-Directed Insertions: Discovery Of Fully Functional Ftsz-Fluorescent Proteins, Desmond A. Moore, Zakiya N. Whatley, Chandra P. Joshi, Masaki Osawa, Harold P. Erickson

Biology Faculty Publications

FtsZ, a bacterial tubulin homologue, is a cytoskeletal protein that assembles into protofilaments that are one subunit thick. These protofilaments assemble further to form a “Z ring” at the center of prokaryotic cells. The Z ring generates a constriction force on the inner membrane and also serves as a scaffold to recruit cell wall remodeling proteins for complete cell division in vivo. One model of the Z ring proposes that protofilaments associate via lateral bonds to form ribbons; however, lateral bonds are still only hypothetical. To explore potential lateral bonding sites, we probed the surface of Escherichia coli FtsZ …