Life Sciences Commons^™

Molecular Characterization Of Stress Response In Western Honey Bee (Apis Mellifera), Faizan Tahir

Master's Theses

Honey bees are incredibly important for the reproduction of flowering plants and the sustainability of agricultural ecosystems. However, they face various stressors such as pesticides, pathogens, habitat loss, and climate change. Extensive research has been conducted to understand how bees respond to these stressors. Scientists have discovered that honey bees exhibit complex physiological and behavioral responses to stress at individual and colony levels. Stress can have a significant impact on their immune function, foraging behavior, and reproductive success (Decourtye et al., 2010). Understanding bee responses to stress is crucial for several reasons. Firstly, honey bees are vital for the pollination …

Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow

Master's Theses

Membrane transporter proteins play the vital role of moving compounds in and out of the cell and are essential for all living organisms. ATP Binding Cassette (ABC) family transporters function both as importers and exporters in prokaryotes. MetNI is an E. coli Type I ABC transporter responsible for the uptake of methionine into the cytosol from the cell periplasmic space through the cell membrane to maintain intracellular methionine pools. ABC transporters, like other membrane proteins, are most often mechanistically and structurally studied in vitro, solubilized by detergents. However, detergent micelles may affect the conformational changes of membrane proteins relative to …

Solving The Cable Equation, A Second-Order Time Dependent Pde For Non-Ideal Cables With Action Potentials In The Mammalian Brain Using Kss Methods, Nirmohi Charbe

Master's Theses

In this thesis we shall perform the comparisons of a Krylov Subspace Spectral method with Forward Euler, Backward Euler and Crank-Nicolson to solve the Cable Equation. The Cable Equation measures action potentials in axons in a mammalian brain treated as an ideal cable in the first part of the study. We shall subject this problem to the further assumption of a non-ideal cable. Assume a non-uniform cross section area along the longitudinal axis. At the present time, the effects of torsion, curvature and material capacitance are ignored. There is particular interest to generalize the application of the PDEs including and …

Characterizing The Dynamic Localization Of Cmi In Early Drosophila Development, Asra Habibullah

Master's Theses

The COMPASS-like family of lysine methyltransferases, MLR/MLX complexes, are epigenetic regulators that are essential for normal development through the methylation of the fourth lysine residue on histone 3 (H3K4), a universal epigenetic mark associated with active transcription. This family of complexes is highly conserved from yeast to mammals and the genes encoding the human MLR complexes have been associated with various developmental diseases and cancers (Dingwall and Fagan, 2019). In D. melanogaster, the enzymatic methyltransferase core of this complex is composed of two proteins: Cara Mitad (Cmi, also known as Lpt) and Trithorax-related (Trr). Although these proteins have been shown …

Characterization Of The Full-Length Bag3 Protein And Stress Induced Formation Of Bag3-Z, Ahmed Gamal Abdalla Zied

Master's Theses

Bcl2-associated athanogene-3 (BAG3) is a pro-autophagy co-chaperone that we havepreviously shown localizes to the cardiac sarcomere and is critical for proteostasis and maintenance of normal sarcomeric function. Indeed, BAG3 loss in heart failure (HF) results in accumulation of ubiquitinated sarcomeric proteins, and depressed maximum force generating capacity (Fmax). However, how BAG3 is regulated in the cell is not well understood, with uncertainty about its structure and proteoforms. During our analysis of human heart tissue, BAG3 appears as a “doublet”, with one band at 74 kDa (BAG3-Z) and a second at a higher 85 kDa (BAG3-FL). Previous studies hypothesized the full-length …

The Impacts Of Framework Mutations On Steady-State Kinetics Of An Aldolase Abzyme, Charles Andrew Mettler

Master's Theses

During affinity maturation, antibodies acquire point mutations that lead to enhanced binding strength to a particular ligand while simultaneously becoming more conformationally restricted as they become increasingly complementary to their ligand’s electrostatic geometry. This property has catalytic potential in transition-state (TS) stabilization whereby kinetic barriers (i.e., the energetic gap between the substrate and its TS) are reduced and reaction rates are enhanced. This basic mechanism is thought to underlie the majority of the rate enhancement observed for enzymes. A key integration of antibody binding specificity and strength with enzymatic catalytic strategy is the development of catalytic antibodies (“abzymes”). Abzymes are …

Mechanisms Of Substrate Selectivity And Transport By Escherichia Coli Atp- Binding Cassette (Abc) Transporter Metni, Yuchun Chen

Master's Theses

ABC transporters are central in many cellular functions including nutrient uptake, signal transduction membrane assembly, and cellular detoxification. Both structural and functional studies have revealed insights into the high-affinity uptake mechanism of the MetNI methionine ABC transporter. Using the energy from ATP binding and hydrolysis, the MetNI-Q system can import L-Met, D-Met, and other methionine derivatives against concentration gradients. Many mechanistic studies of ABC transporter propose a model in which cognate binding proteins sequester substrates in the periplasm and deliver them to the transporter. In contrast, recent in vivo and crystallographic studies of MetNI-Q suggest that some substrates may be …

Investigation Of Dna Variability And Phylogenetic Relationships Of Perlesta (Plecoptera: Perlidae) In Mississippi, James C. Valentine, Mac H. Alford

Master's Theses

The genus Perlesta Banks, 1906 (Plecoptera: Perlidae) consists of 35 species, 33 native to the United States and Canada and two native to China. For over a century these small, brown stonefly adults and freckled yellow nymphs have gone by the name of the type species of the genus, Perlesta placida, but taxonomic work in the genus since 1989 has resulted in the recognition of additional species. These species were mostly recognized and described using morphological characteristics, but two areas that are lacking include (1) linking nymphs to adults and (2) phylogenetic analysis of all species occurring in Mississippi …

Examination Of Methylation Status And Occupancy Of Dna Methylation Modifying Proteins On Regulatory Regions Of The Dax-1 Gene, Caroline P. Riedstra

Master's Theses

Epigenetic modifications influence gene expression and thereby play a pivotal role in development and disease. Misregulation and mutations in the DAX-1 gene, or Dosage-Sensitive Sex Reversal, Adrenal Hypoplasia Congenita, Critical Region on the X chromosome, gene 1, have been implicated in Adrenal Hypoplasia Congenita (AHC) and Dosage Sensitive Sex Reversal (DSS). The orphan nuclear hormone receptor DAX-1 is expressed predominantly in tissues such as the testes, ovaries, breast, adrenal cortex, and lung. Critically, DAX-1 may serve as an indicator of aberrant growth in these tissues. Here we hypothesize that DAX-1 is epigenetically regulated, specifically in cancer cells, thereby reducing its …

Polycyclic Aromatic Hydrocarbons And The Microbiomes Of Two Benthic Species, Samantha Ells

Master's Theses

The presence of oil has been shown to affect the microbiomes of the water column, sediments, and organisms, both by altering the diversity and the composition of those microbial communities. If the microbiome is altered it may no longer provide benefits to its host organism, impacting its ability to survive. Thus, it is important to understand the effects of large-scale contamination events including the Deepwater Horizon oil spill. This study set out to examine the effects of oil exposure on the microbiome of two benthic species, southern flounder (Paralichthys lethostigma) and eastern oysters (Crassostrea virginica) to further understand the effects …

Investigating The Mechanism Of The Escherichia Coli Atp-Binding Cassette (Abc) Transporter Metni, Matthew Foronda

Master's Theses

Chemical homeostasis is a baseline requirement for any cell to survive. ATP-binding cassette (ABC) transporters play a vital role in homeostasis by importing nutrients and exporting toxins against their concentration gradients by utilizing the energy of ATP hydrolysis. Malfunctioning ABC transporters cause a variety of health problems, including cystic fibrosis, Stargardt’s disease (vision loss), and the development of drug-resistant tumors. An important step in solving these medical issues is to first understand the structure and mechanism of ABC transporters. Various studies have made great strides in depicting the structure and details of different ABC transporters and their mechanisms, however, many …

Function Of Mllt3 In Liver Metabolism, Grace Ann Hammack

Master's Theses

The chromatin regulator MLLT3 recognizes target genes through the YEATS domain that identifies post-translationally modified histones, with preference for crotonyl and acetyl marks, and recruits different multiprotein effector complexes through its C-terminal domain to target genes. To study the role of MLLT3 in gene regulation, the Zeleznik-Le and Hemenway labs developed Mllt3 whole-body knockout (Mllt3;Rosa26-CreERT2) mice. These mice have a hematopoietic stem cell phenotype and an unexpected obesity and hepatic steatosis phenotype. It was unknown whether these phenotypes were from liver intrinsic effects or influenced by other parts of the body. To study this fatty liver phenotype further, Mllt3;Alb-Cre were …

Beta-Adrenergic Receptor Mediated Transcriptional Dysregulation In Hematopoeitc Stem And Progenitor Cells Leads To Bone Marrow Erythroid Suppresion In Multiple Myeloma Patients - Ex Vivo Investigations, Vimal Ravi Subramaniam

Master's Theses

The sympathetic nervous system (SNS) regulates our body’s involuntary response to stress or harm. Once activated, it releases hormones and neurotransmitters known as catecholamines throughout the body to mediate its recovery. The catecholamines bind to adrenergic receptors located on various cells in a process designated as adrenergic signaling to elicit this response. This process is not always to our benefit. Adverse symptoms such as anemia can result due to adrenergic signaling. Our laboratory previously showed that burn injury triggers adrenergic receptor stimulation resulting in anemia induced by diminished erythropoiesis. The development of anemia in these studies was found to be …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Analysis Of Biofilm Remediation Capacity For Octenyl Succinic Anhydride (Osa), A Bioactive Food Starch Modifier Compound, Matthew R. Borglin

Master's Theses

Matthew R. Borglin

This thesis demonstrates efficacy of Octenyl Succinic Anhydride (OSA), as a biofilm sanitizer. Biofilms allow bacteria to adhere to solid surfaces with the use of excreted polymeric compounds. For example, surfaces found in food production or processing facilities such as the interior of a raw milk holding tank, are some of the most susceptible to biofilm contamination. When present, biofilms can cause a variety of negative effects, which include; reduction of product shelf life, corrosion, and outbreaks of foodborne illnesses. The close association of biofilms with the majority of foodborne illness cases led the US Environmental Protection …

An Assessment Of Convergence In The Feeding Morphology Of Xiphactinus Audax And Megalops Atlanticus Using Landmark-Based Geometric Morphometrics, Edward Chase Shelburne

Master's Theses

Convergence is an evolutionary phenomenon wherein distantly related organisms independently develop features or functional adaptations to overcome similar environmental constraints. Historically, convergence among organisms has been speculated or asserted with little rigorous or quantitative investigation. More recent advancements in systematics has allowed for the detection and study of convergence in a phylogenetic context, but this does little to elucidate convergent anatomical features in extinct taxa with poorly understood evolutionary histories. The purpose of this study is to investigate one potentially convergent system—the feeding structure of Xiphactinus audax (Teleostei: Ichthyodectiformes) and Megalops atlanticus (Teleostei: Elopiformes)—using a comparative anatomical approach to assess …

The Democratization And Development Of Cell-Free Protein Synthesis, Max Z. Levine

Master's Theses

Cell-free protein synthesis (CFPS) using crude lysates has developed into a robust platform technology over the last 60 years to express numerous types of recombinant proteins. The open-nature, elimination of reliance on cell viability, and focus of all energy towards production of the protein of interest represent substantial advantages of CFPS over in vivo protein expression methods. CFPS has provided new opportunities across a series of research fields that include metabolic engineering, therapeutic and vaccine development, education, biosensors, and many more. In recent years, optimizations of CFPS have even allowed the platform to reach the industrial level of protein production. …

Study Of Paper Microbial Fuel Cells For Use In On-Site Wastewater Testing, William A. Tolmasoff

Master's Theses

This study demonstrated a technique for fabricating simple, low-cost Paper Microbial fuel cells (PMFC’s) in the model of a previous study to, for the first time, produce voltage from wastewater effluent. The PMFC’s were created by stacking and gluing the main components of an MFC together: reservoir layer; anode; cation exchange membrane (CEM); air cathode. A wax printer was used to create the hydrophobic borders of the PMFC’s on filter paper, and graphite paint was applied to the paper to create the anode. The CEM’s considered were filter paper, wax, and Nafion, with Nafion being the most efficient. Finally, the …

Naatm1: Examining The Mechanism Of A Heavy-Metal Abc Exporter, Dennis Hicks

Master's Theses

ATP-Binding Cassette (ABC) Transporters are a superfamily of integral membrane proteins that have been found embedded in both the cellular membranes and internal organelles of all species yet analyzed (1). This extreme conservation throughout the tree of life is due to their vitally critical and broad task of transporting all manner of things into and out of the cell and related organelles. This broadness of responsibility has led to an abundant diversity of this family, which in turn, has allowed life to adapt to the many environments found on Earth. While the importance and variability of this family is abundantly …

Mllt3 Regulates Expression Of Genes Critical To Liver Metabolic Homeostasis, Jonathan Richard Dixit

Master's Theses

Hepatic steatosis (fatty liver) is increasingly prevalent in the US, and is characterized by triglyceride accumulation within hepatocytes. This is a direct result of an imbalance between lipid import, export, de novo lipogenesis, and beta oxidation. Hepatic steatosis can also progress to nonalcoholic steatohepatitis (NASH) which is characterized by increased hepatocyte damage, inflammation, and fibrosis. Further progression can lead to liver failure or hepatocellular carcinoma, requiring liver transplant or causing death. Our lab recently created Mllt3 conditional whole body knockout mice. These mice developed hepatic steatosis and NASH following Mllt3 deletion. MLLT3 is a master gene regulator that is part …

Characterizing The Requirement Of The Cmi/Trr Compass-Like Complex During Drosophila Development, Timothy Nickels

Master's Theses

The MLR family of COMPASS-like complexes are histone methyltransferase complexes that are associated with the activation of gene enhancers. In D. melanogaster, Cara mitad (Cmi, also known as Lpt) and Trithorax related (Trr) are central subunits of a complex orthologous to mammalian Lysine methyltransferase 2 C and D (KMT2C and KMT2D, also known as MLL3 and MLL2/4) that catalyze H3K4 monomethylation. Previous studies have demonstrated that mutations in these genes are associated with cancer and developmental disorders, but the mechanisms by which these alterations contribute to disease states are unknown. The Cmi-containing COMPASS-like complex and orthologous vertebrate complexes have been …

Inhibition Of Mutant Egfr In Nsclc Promotes Endothelin-1-Mediated Nsclc Disease Progression, Stephen Ollosi

Master's Theses

Angiogenesis in NSCLC has been identified as important therapeutic target in combination with EGFR TKIs. However, only small incremental advancements have been made for the use of angiogenesis inhibitors in NSCLC and it remains elusive why the inhibition of VEGF-mediated neovascularization is not therapeutically efficacious. I present experimental evidence that a subpopulation of NSCLC cells with EGFR TKI-induced EMT contributes toward the attenuation of the response to EGFR TKI therapy. One of the hallmarks of cancer is heterogeneity and I have previously demonstrated that tumor heterogeneity within NSCLC cells lines harboring EGFR kinase domain mutations gives rise to divergent resistance …

Characterization Of Andrenocortical Tissue Morphology, Histology, And Steroid Synthesis Among Finetooth (Carcharhinus Isodon), Blacktip (Carcharhinus Limbatus), Atlantic Sharpnose (Rhizoprionodon Terraenovae), And Bonnethead (Sphyrna Tiburo) Sharks, Danielle Elizabeth Bailey

Master's Theses

Adrenocortical (interrenal) tissue is composed of steroidogenic cells that produce corticosteroids involved in the stress response and hydromineral balance. Previous research characterizing the elasmobranch interrenal suggests that the number of interrenal bodies that produce the single primary corticosteroid, 1a-hydroxycorticosterone (1a-OHB), varies among species. However, potential species-specific differences in the amount of interrenal tissue and major steroid products produced have been understudied. To address this critical gap in our understanding of elasmobranch biology, this study examined interrenal morphology, cell structure, steroidogenic enzyme distribution (3bHSD), and steroid production in four shark species: Finetooth Carcharhinus isodon, Blacktip Carcharhinus limbatus, Atlantic Sharpnose …

An Assessment Of Potential False Positive E.Coli Pyroprints In The Cplop Database, Skyler A. Gordon

Master's Theses

The genetic information found in each species of organism is unique, and can be used as a tool to differentiate at the molecular level. This has caused rapid genotyping methods to become the cornerstone of a new area of research dependent on reading the genome as a form of identification. One of these specific identification methods, known as pyroprinting, relies on the small variation of DNA sequences within the same species to develop a unique, reproducible fingerprint. By simultaneously pyrosequencing multiple polymorphic loci within the ribosomal operons known as the intergenic transcribed spacers, a reproducible output is obtained, known as …

Utilizing Single-Molecule Fret Methods To Study Conformational Changes In Trim5Α, Margret Suzanne Bradley

Master's Theses

Single-molecule FRET (smFRET) is a method by which dynamic conformational changes can be monitored in a protein microscopically and in real time. smFRET relies on the creation of FRET (Förster Resonance Energy Transfer) between small molecule fluorophores conjugated to the biomolecules of interest. FRET efficiency allows calculation of interfluorophore distances. Changes in FRET efficiency represent changes in protein conformation which can inform further structural and molecular studies of the protein of interest. For example, in the Campbell Lab, we study the protein TRIM5α, an antiretroviral cellular protein which can cause premature dissociation of the HIV capsid core by an unknown …

Potential Efficacy Of Targeting Mll1 In Breast Cancer, Austin Gable Holmes

Master's Theses

In 2017, it is estimated that breast cancer will be the most prevalent newly diagnosed cancer in females, at 30% in the U.S. alone1. From the early 1990s to 2014 the death rate in females from breast cancer has dropped by 10% but still stands as the second highest cancer related death in females in the U.S.2. One of the biggest hurdles in breast cancer research is disease heterogeneity. New mechanisms of disease development and progression are encountered frequently. One mechanism studied in the past decades is epigenetics. It has been theorized that the cancer epigenome can maintain an abnormal …

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe-Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given …

Reconstitution Of Munc18-Dependent Mast Cell Degranulation, Matthew Grant Arnold

Master's Theses

Mast cells are specialized secretory leukocytes that play diverse roles in the body, mediated by release of histamine and other pharmacologically active substances. Although offering essential protection in innate and adaptive immunity, mast cells are also essential to the progression of inflammatory diseases, including allergy and asthma, (Theoharides et al., 2012). Exocytosis of pro-inflammatory mast cell mediators in response to otherwise innocuous antigens relies on evolutionarily-conserved membrane fusion machinery. These proteins, called SNAREs are regulated by the Sec1/Munc18 (SM) protein family (Axle Lorentz, Baumann, Vitte, & Blank, 2012). Mast cells express three mammalian Munc18 isoforms (a, b, and c), which …

Role Of Pkc Delta In Uv Radiation Dna Damage Repair, Gargi Patil

Master's Theses

DNA damage caused by ultraviolet radiation (UV), such as cyclobutane pyrimidine dimers (CPD), is repaired by the nucleotide excision repair (NER) pathway. When NER is defective, DNA damage is not repaired, leading to mutations and skin cancer. After DNA damage, the cell cycle is halted at various checkpoints to allow time for repair of the damage and maintain genomic integrity, however little is known about the coordination between NER DNA damage repair and cell cycle halting at checkpoints after DNA damage. Protein kinase C δ (PKCδ) plays major role in apoptosis and maintains the G2/M checkpoint in response to UV …

A Bioluminescence Sensor Of Nlrp3 Inflammasome Activation, Michael Alexander Winek

Master's Theses

The innate immune system is many organisms first line of defense against pathogenic insult or tissue damage. This defense strategy is intent on restoring homeostasis upon perturbation. Upon activation of the innate immune system in humans, an oligomeric protein complex termed the “Inflammasome” forms in myeloid cells. The canonical output of activation of any subset of inflammasome is Caspase-1-mediated secretion of pro-inflammatory cytokines IL1β and IL18. Chronic or uncontrolled inflammasome activation is at the core of myriad economically burdening diseases. In many of these diseases, endogenous factors chronically engage the innate immune system. To study these diseases in in vivo, …