Biochemistry, Biophysics, and Structural Biology Commons^™

Bang!: Real-Time Measurements And Transcriptomics Of Metabolic Reprogramming In Activated Macrophages At Fever Temperature, Kenneth Howard Taylor

Graduate Theses and Dissertations

We investigated the real-time metabolic rates of activated macrophage cell lines derived from mouse, chicken and rainbow trout. Each species showed a different kinetic signature with metabolic rates accelerating under fever conditions specific to each organism. Upon activation mouse macrophages increased their rate of glycolysis early and then a later reprogramming phase occurred with a dramatic decrease in oxidative phosphorylation (OXPHOS) accompanied by a reciprocal second increase in glycolytic rates. Chicken macrophages showed an initial increase in both glycolytic and OXPHOS rates. The late drop OXPHOS rates also occurred in chicken however there was no reprogramming that occurred as glycolytic …

Eepd1 Evolved A Unique Dna Clamping Dimer Protecting Reversed Replication Forks, Runze Shen

Dissertations and Theses (Open Access)

Exonuclease/endonuclease/phosphatase (EEP)-fold hydrolases are canonically monomeric phosphodiesterases exemplified by APE1, DNase I, and TDP2 nucleases. While EEP superfamily domain-containing protein 1 (EEPD1) acts in DNA stress responses, its proposed nuclease activities are enigmatic. Here, we integrate hybrid structural methods, evolution, biochemistry, cancer genomics, molecular and cell biology to define EEPD1’s structure, assembly, and function at stalled DNA replication fork intermediates. Combined results show that EEPD1 surprisingly requires both the unique EEP domain dimer and distinctive tandem Helix-hairpin-Helix [(HhH)₂] domains to clamp double-stranded(ds) DNA at reversed DNA replication forks for fork protection. X-ray scattering, crystal, and cryo-EM structures unveil …

Role Of Mir-4732-3p In Breast Cancer Brain Metastasis And Brain Metastatic Tumor Microenvironment, Munazza Samar Khan

Dissertations and Theses (Open Access)

In this study, we aimed to identify microRNAs (miRNAs) that may play important roles in breast cancer brain metastasis (BCBM). To this end, we conducted miRNA-sequencing of extracellular vesicles isolated from the serum samples of 6 BCBM patients and 8 Stage I/II/III breast cancer patients, and identified 49 circulating miRNAs that were upregulated in BCBM patients compared to Stage I/II/III breast cancer. Upon further analysis, we identified miR-4732-3p to be upregulated in brain-tropic triple-negative breast cancer (TNBC) cell lines, compared to parental lines. MiR-4732-3p overexpression increased metastatic properties of TNBC cells, including proliferation, migration, invasion, and maintenance of a mesenchymal …

Regulation Of Ccr7 Signaling Events By G-Protein-Coupled Receptor Kinases 2 And 3, Anahi Sanchez

Open Access Theses & Dissertations

G protein-coupled receptors (GPCR) can bind multiple ligands, leading to differential signaling events termed biased signaling. C-C chemokine receptor 7 (CCR7) is a GPCR known to have biased signaling between the two ligands it binds to, CCL19 and CCL21. Binding of C-C Chemokine Ligand 19 (CCL19) promotes a high level of CCR7 phosphorylation, while CCL21 leads to a much lower level of CCR7 phosphorylation; findings observed in HEK and dendritic cells. GPCR kinases (GRKs), which can control the phosphorylation patterns of a GPCR, are hypothesized to regulate biased signaling of a receptor. GRK expression differs between cell lines and cell …

Developing A Small Molecule To Inhibit Hsf1 Expression In Cancer And Evaluating Natural Genetic Variation In Small Molecule Toxicity., Michaela Kendal Foley

Theses and Dissertations

Each year cancer affects nearly 20 million people worldwide and genetic differences across populations can impact cancer onset and progression. Specifically, tumors with high levels of HSF1, the master regulator of the cytoprotective heat shock response (HSR), are correlated with poor patient outcomes in multiple cancers such as prostate, breast, and melanoma. Subsequently, the development of pharmacological inhibitors of HSF1 represents a promising strategy for anticancer therapeutics. Using a luciferase-based transcriptional reporter, two small molecule libraries were screened for inhibitors of HSF1 expression in human embryonic kidney cells, yielding ten compounds that decrease HSF1 expression. To identify if cancer lines …

Neuronal Cftr: A Study Of Subcellular Localization And Interactions With Implications For A Role In Synaptic Transmission, Brandon J. Leviskas

LSU Doctoral Dissertations

Protein-protein interactions vary among cell types and the localization of these interactions help to define protein function. The function of cystic fibrosis transmembrane conductance regulator (CFTR) is well established in the context of epithelial tissue due to the debilitating effects of its mutations that cause the disease cystic fibrosis. While in neurons a role has been established in our lab for CFTR in the regulation of cytosolic Cl- in retinal amacrine cells (ACs). This research sets out to learn if CFTR has a synaptic role. Exploring this potential role, localization of CFTR was examined using fluorescent and immunogold labeled transmission …

Metabolic Transitions In Embryos Of Artemia Franciscana: Regulation And Consequences For Oxidative Stress, Daniel Anthony Arabie

LSU Doctoral Dissertations

Embryos of Artemia franciscana survive harsh conditions in diapause and anoxia-induced quiescence for years by undergoing deep metabolic transitions. I investigated the relationship between phosphorylation of pyruvate dehydrogenase (PDH) and carbon flux to the tricarboxylic acid (TCA) cycle during metabolic depression. The difference in catalytic activity of the PDH complex (PDC) in maximally phosphorylated and dephosphorylated samples was 16.5-fold. Western blot analysis confirmed the changes in phosphorylation of PDH. Analysis of PDH expression in diapause and post-diapause embryos via phospho-PDH showed no significant differences. Investigation of post-diapause embryos under anoxia showed that phosphorylation of PDH decreased and activated the enzyme. …

Investigation Of The Effects Of The Peptidylarginine Deiminase Inhibitor Cl-Amidine On Apoptosis And Gene Expression In Ovarian Cancer, Victoria Walden

Longwood Senior Thesis Proposal

Peptidylarginine deiminases (PADs) are a family of enzymatic proteins responsible for the conversion of arginine and methylarginine residues to citrulline. This conversion is important for several key cellular processes including transcriptional gene regulation. Recently, a link has been established between overexpression of a particular PAD, PAD4, and the accelerated progression of both autoimmune diseases and cancers. Ovarian cancer exhibits heightened levels of PAD4 in affected cells. High levels of PAD4 are associated with the formation of neutrophil extracellular traps (NETs) that promote cancer metastasis, and downregulation of the p53 apoptotic pathway. Thus, it is important to explore inhibitors of PAD4. …

Steroid Receptors And Coregulators: Dissemination Of Sex Differences And Emerging Technologies, Sally Pauss, Evelyn A. Bates, Genesee J. Martinez, Zane T. Bates, Zachary A. Kipp, Cassandra D. Gipson, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Steroid receptors are ligand-induced transcription factors that have broad functions among all living animal species, ranging from control of sex differences, body weight, stress responses, and many others. Their binding to coregulator proteins is regulated by corepressors and coactivators that interchange upon stimulation with a ligand. Coregulator proteins are an imperative and understudied aspect of steroid receptor signaling. Here, we discuss steroid receptor basics from protein domain structures that allow them to interact with coregulators and other proteins, their essential functions as transcription factors, and other elemental protein–protein interactions. We deliberate about the mechanisms that coregulators control in steroid receptor …

Ccr7 Regulated Mechanisms That Limit The Adaptive Immune Response, Jaisel Amilcar Cervantes

Open Access Theses & Dissertations

C-C chemokine receptor 7 (CCR7) is critical in guiding T cell migration within the thymus and peripheral lymphoid tissues, shaping the adaptive immune response by promoting central tolerance and regulating immune homeostasis. Although its role in lymphocyte trafficking is well established, the molecular mechanisms by which CCR7 influences thymocyte development and T cell receptor (TCR) repertoire formation remain less understood. This study examines how CCR7 deficiency impacts thymic selection, TCR diversity, and the signaling events that shape repertoire restriction. Using a homozygously deleted CCR7 murine model, we found that the absence of CCR7 results in a less restricted TCR repertoire …

Painting Rich Six-Dimensional Pictures Using Polarized Fluorescence Microscopy, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

No abstract provided.

Dnajb6: A Potent Dnajb Chaperone In Regulating Tau Proteostasis, Abigail R. Esquivel

USF Tampa Graduate Theses and Dissertations

Neurodegenerative diseases often feature the pathological buildup of misfolded proteins, and tau is a principal culprit in multiple tauopathies. One chaperone of emerging interest is DnaJB6b, a member of the Hsp40/DnaJ family, which exhibits potent anti-aggregation activity against several disease-related proteins. Recent investigations highlight its unique capacity to recognize and neutralize aggregation-prone forms of tau. DnaJB6b appears potent against multiple variants of tau and may be acting against tau, in part, by directing misfolded tau toward proteasomal clearance. The first lines of evidence come from systematic chaperone screens, where DnaJB6b repeatedly emerged as a strong suppressor of tau seeding. Further …

Uca1 As A Key Regulator Of The Warburg Effect During Anoikis Resistance In Colorectal Cancer Metastasis, Ricardo Pequeno Bracho, Salique Hassan Shaham, Yamile Abuchard Anaya, Sophia Leslie, Kyle Doxtater, Subhash Chauhan, Bilal Hafeez, Tamer Oraby, Manish K. Tripathi

Research Symposium

Colorectal carcinoma (CRC) is the second leading cause of cancer-related mortality in the United States. While localized CRC has a 90% five-year survival rate, this drops sharply to 14% upon metastasis. Metastasis occurs in approximately 40–50% of CRC cases and requires cancer cells to acquire anoikis resistance—a critical adaptation allowing survival after detachment from the extracellular matrix, enabling migration and colonization of secondary sites. Understanding the molecular mechanisms driving anoikis resistance, particularly those linked to altered glucose metabolism, is essential for developing targeted therapies for metastatic CRC.

Cancer cells frequently exhibit the Warburg Effect, a metabolic adaptation favoring glycolysis over …

Cargo Hitchhiking Autophagy - A Hybrid Autophagy Pathway Utilized In Yeast, Katrina F Cooper

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Macroautophagy is a catabolic process that maintains cellular homeostasis by recycling intracellular material through the use of double-membrane vesicles called autophagosomes. In turn, autophagosomes fuse with vacuoles (in yeast and plants) or lysosomes (in metazoans), where resident hydrolases degrade the cargo. Given the conservation of autophagy,

Overexpression And Biophysical And Functional Characterization Of A Recombinant Fgf21, Phuc Phan, Jason Hoang, Thallapuranam Krishnaswamy Suresh Kumar

Chemistry & Biochemistry Faculty Publications and Presentations

Fibroblast growth factor 21 (FGF21) is an endocrine FGF that plays a vital role in regulating essential metabolic pathways. FGF21 increases glucose uptake by cells, promotes fatty acid oxidation, reduces blood glucose levels, and alleviates metabolic diseases. However, detailed studies on its stability and biophysical characteristics have not been reported. Herein, we present the overexpression, biophysical characterization, and metabolic activity of a soluble recombinant FGF21 (rFGF21). The far-UV circular dichroism spectra of rFGF21 show a negative trough at 215 nm, indicating that the protein’s backbone predominantly adopts a β sheet conformation. rFGF21 shows intrinsic tyrosine fluorescence at 305 nm. Thermal …

Staying Sane In The Membrane: Neutral Sphingomyelinase 2 As A Master Regulator Of Plasma Membrane Ceramide, Zainuddin Quadri, Erhard Bieberich

Markey Cancer Center Faculty Publications

Ceramide, a key signaling sphingolipid in the plasma membrane, plays a pivotal role in fundamental cellular processes such as adhesion, polarity, and programmed cell death. The generation of plasma membrane ceramide is largely attributed to the activity of two types of sphingomyelinases: neutral sphingomyelinase 2 (nSMase2, Smpd3) and acid sphingomyelinase (aSMase, Smpd1). While many studies have explored ceramide generation following experimental activation of these enzymes, the mechanisms governing basal or steady- state ceramide levels have remained poorly understood. Using an innovative mass spectrometry approach developed in the Canals’ lab, the team has quantified the distinct contributions of nSMase2 and aSMase …

Tdp43 Autoregulation Gives Rise To Dominant Negative Isoforms That Are Tightly Controlled By Transcriptional And Post-Translational Mechanisms, Megan M. Dykstra, Kaitlin Weskamp, Nicolás B. Gómez, Jacob Waksmacki, Elizabeth Tank, M. Rebecca Glineburg, Allison Snyder, Emile Pinarbasi, Michael Bekier, Xingli Li, Morgan R. Miller, Jen Bai, Shameena Shahzad, Neha Nedumaran, Clare Wieland, Corey Stewart, Sydney Willey, Nikolas Grotewold, Jonathon Mcbride, John J. Moran, Aditya V. Suryakumar, Michael Lucas, Peter M. Tessier, Michael Ward, Peter K. Todd, Sami J. Barmada

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The nuclear RNA-binding protein TDP43 is integrally involved in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Previous studies uncovered N-terminal TDP43 isoforms that are predominantly cytosolic in localization, prone to aggregation, and enriched in susceptible spinal motor neurons. In healthy cells, however, these shortened (s)TDP43 isoforms are difficult to detect in comparison to full-length (fl)TDP43, raising questions regarding their origin and selective regulation. Here, we show that sTDP43 is created as a by-product of TDP43 autoregulation and cleared by nonsense-mediated RNA decay (NMD). sTDP43-encoding transcripts that escape NMD are rapidly degraded post-translationally via the proteasome …

Investigating The Interactions Between Elm1 And Hsl7 In The Morphogenesis Checkpoint Of Saccharomyces Cerevisiae, Rachel Foster

Masters Theses & Specialist Projects

Cell shape is essential to understanding the normal regulatory processes that occur within the cell and can indicate there are abnormalities present when there is dysfunction in the cell's development, which can have broader implications regarding human disease. The morphogenesis pathway couples cell division to the timely formation of a daughter bud in Saccharomyces cerevisiae and consists of Elm1, Hsl1, Hsl7, and Swe1 proteins which interact with septins at the bud neck to provide stability for the bud and to facilitate cell division. Elm1 is needed for the recruitment of Hsl1 and subsequently Hsl7. Hsl7 will then tether Swe1 to …

Cdh-3/Cadherin, Yap-1/Yap And Egl-44/Tead Promote Syx-2/Syntaxin And Eff-1 Fusogen-Mediated Phagosome Closure, Alec Whited, Aladin Elkhalil, Ginger Clark, Piya Ghose

Biology Theses - Archive

Physical interactions between cells, such as cell-cell junctions, can profoundly impact cell fate. A vital cell fate for normal development and homeostasis is programmed cell death. Cells fated to die must be efficiently cleared away via phagocytosis, and defects are associated with a variety of diseased states. Whether cell-cell physical associations affect programmed cell elimination has not been well-explored. Here we describe, in vivo, a cell-cell adhesion-driven signaling pathway that ensures compartment-specific cell clearance during development. We previously described the specialized cell death program “Compartmentalized Cell Elimination” (CCE) in the C. elegans embryo. During CCE, the tail-spike cell (TSC), a …

Characterization Of The Erv41-Erv46 Complex As A Retrograde Receptor For Misfolded Secretory Proteins, John Andrew Fuesler

Dartmouth College Ph.D Dissertations

The Endoplasmic Reticulum (ER), the site of secretory protein biosynthesis

provides a favorable environment to promote polypeptide folding, protein

oligomerization and export. Although the ER contains many chaperones and other

factors that assist in protein folding, this process is error prone. Eukaryotes have

evolved protein quality control checkpoints to maintain homeostasis in the secretory

pathway, however these processes are imperfect and may result in proteotoxicity

when toxic levels or aggregates of proteins arise. Mutations in proteins involved in

trafficking in the early secretory pathway are closely associated with disease states.

Therefore, it is of great interest to further understand how …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

Systematic Review Of Immunohistochemistry Protocols, Arpitha Parthasarathy

Pitzer Senior Theses

Immunohistochemistry (IHC) is an essential technique in biological research that allows for the visualization and localization of proteins within tissue samples. This systematic review analyzes the most effective, efficient and reproducible protocols for IHC. It focuses on three critical steps: freezing, cryosectioning, and staining of skeletal muscle tissues in mice models. A total of 41, 44, and 48 articles on freezing, cryosectioning, and staining techniques, respectively, were analyzed, from reputable sources in biology like PubMed and Web of Science. Results showed the following. For freezing, the use of isopentane combined with liquid nitrogen appeared to be the best method, minimizing …

Characterization Of Dietary And Hormonal Influences On Renal Sodium Transporters And Channels In Rodent Models, Evelyn Chan

Scripps Senior Theses

Within kidneys, a diverse array of renal epithelial cells works to maintain electrolyte and water balance to regulate blood pressure and pH. These cells contain varying types of sodium transporters that adjust sodium reabsorption according to the body’s needs. Previous studies have observed sex-specific differences in renal sodium transporter regulation, which are thought to optimize reproduction in females. In this study, we performed high resolution microscopy and detailed characterization of cell type-specific expression and localization of major sodium transporters and channels in rodents in response to dietary and hormonal influences. Specifically, we examined the impact of dietary salt intake and …

Caspases Protect Against Hyperglycemia Induced Necroptosis-Like Cell Death In Brain Endothelial Cells, Aleena S. Mathew

Theses and Dissertations

Acute diabetes characterized by high spikes in blood glucose levels in association with severe hyperglycemia can lead to an increased risk of ischemic stroke in the brain. To better understand high blood glucose levels, hyperglycemia, in the brain we explored its effects on endothelial cells. Endothelial cells line the inner walls of blood vessels and are directly impacted in hyperglycemia. Brain endothelial cells are a major component of the blood brain barrier (BBB) which tightly regulates the brain’s microenvironment. The type of cell death such as apoptosis, caspase dependent, or necroptosis, caspase independent, can exacerbate diabetes associated complications. There is …

Bridging The Gap Between Structural And Cellular Biology: Insight Into The Organization Of Glycolytic Enzymes In Cells, Heather Hansen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glycolytic enzymes are spatially organized in the cytoplasm, and are shown to localize with cellular structures such as the plasma membrane, F-actin, mitochondria, or associate independently within the cytosol. The assembly of these enzymes is hypothesized to regulate pathway flux to meet the energetic needs of the cell. However, it is unclear whether all of these assemblies have the same mechanism of formation or function in the cell. We investigated the role of glycolytic enzyme assemblies in cells, using the glycolytic “gatekeeper” enzyme phosphofructokinase-1 (PFK1). PFK1 is extensively regulated by multiple mechanisms, including over 20 allosteric ligands, post translational modifications, …

Biomechanics Of The Atherosclerotic Lipidome: (Un)Expected Statin Interactions And Membrane Remodelling, Ethan M. Fong

Pomona Senior Theses

Statins interact with lipid membranes in ways that shape their pharmacokinetics, off-target effects, and pleiotropic actions, yet these interactions' mechanical and biophysical consequences remain poorly understood. This thesis employs a combination of surface plasmon resonance (SPR), quartz crystal microbalance with dissipation monitoring (QCM-D), and rheological modelling to characterize how representative statins intercalate within biomimetic supported lipid bilayers (SLBs) of healthy and diseased composition. SPR reveals that lipophilic statins exhibit higher apparent affinities and slower dissociation kinetics, especially in cholesterol- and anionic lipid-rich membranes. QCM-D analyses demonstrate that statins alter membrane mass, dissipation, and interfacial stiffness in a statin- and membrane-dependent …

Temporal Dynamics Of Programmed Genome Rearrangement In Sea Lamprey Embryogenesis: A Deep Learning & Lightsheet Imaging Approach To Studying Early Developmental Transitions, Kasturi Rajandran

Theses and Dissertations--Biology

Programmed genome rearrangement (PGR) in the sea lamprey (Petromyzon marinus) leads to the elimination of ~0.5Gb (20%) of the germline genome during early embryogenesis, yet its timing relative to the maternal-to-zygotic transition (MZT) remains unclear. In this study, we imaged embryos cleared at 3-hour intervals (up to 72 hours post fertilization (hpf)) using high-resolution lightsheet fluorescence microscopy and a custom deep-learning image-analysis pipeline (~80% accuracy) to quantify nuclei and micronuclei counts. Micronuclei, which are the hallmarks of PGR first appear between 24 to 27hpf (vs ~36hpf previously reported) indicating PGR starts earlier than previously reported in the sea …

Functional Analysis Of Ligand Binding Domain 2 Of Outer Surface Protein C Of Borreliella Burgdorferi, Gavin Z. Chambers

Theses and Dissertations

Lyme disease, caused by the spirochete Borreliella burgdorferi, is the most common vector-borne infection in North America. A critical determinant of early mammalian infection is outer surface protein C (OspC), a highly variable lipoprotein that is indispensable for spirochete survival but whose precise function remains unresolved. OspC has been proposed to mediate diverse roles, including complement evasion, adhesion, tissue dissemination, and antiphagocytic activity, supporting the view that it is a multifunctional virulence factor. Structural studies have identified two putative ligand-binding domains (LBD1 and LBD2), with LBD2 forming a solvent-exposed crown at the membrane-distal end of the OspC dimer.

To …

Unleashing Serine Palmitoyltransferase In Test Tubes And Mice, Matthew W. Peart

Theses and Dissertations

Canonically known both for structural contributions to lipid bilayers and roles in cell signaling, the sphingolipids comprise a dynamic, multifaceted class of molecules which are studied to understand homeostatic cell biology as well as pathophysiology. Sphingolipids contribute to tissue-specific structures such as myelin, a multilayer membrane that allows for rapid conduction of action potentials along neuronal axons. All sphingolipids are downstream products of the rate-limiting and initiating enzyme in the de novo sphingolipid synthesis pathway, Serine palmitoyltransferase (SPT). Demonstrative of its status as the enzyme that catalyzes a crucial step in a biochemical pathway, SPT activity is strictly regulated. This …

Exploring The Effects Of Road Salt On Earthworm Species, Alea Mry Koston

Williams Honors College, Honors Research Projects

This study examines the effects of two road salts, sodium chloride (NaCl) and calcium magnesium acetate (CMA), on the health of two earthworm species: Eisenia fetida and Lumbricus terrestris. Over a 4-week period, approximately 168 earthworms were exposed to varying concentrations of either NaCl, CMA, or mixed ratios of both, with a control group included for comparison. The experiment involved monitoring the changes in earthworm weight and measuring their contraction rates to determine physiological responses. Statistical analysis revealed no significant differences in weight or activity between NaCl and CMA treatments for either species. However, higher concentrations of NaCl resulted in …