Other Cell and Developmental Biology Commons^™

The Biobehavioral Effects Of Embryonic Exposure To Neural Inflammation And Oxidative Stress In Zebrafish, Dalton J. Anderson

Honors College Theses

The purpose of this research is to improve understanding of the neurodevelopmental effects of embryonic exposure to elevated inflammation and oxidative stress induced by the antipyretic drug acetaminophen (APAP). Our study was the first to examine the interactive effects of APAP and inflammation in zebrafish embryos and how the treatments affect brain development and larval behavior. Experimental groups of zebrafish larvae were exposed to lipopolysaccharide (LPS) to induce inflammation, APAP, or LPS + APAP and larval behavior was analyzed using Ethovision automated behavioral tracking software. We also measured changes in whole-brain Glycogen Synthase Kinase 3 Beta (GSK3B) and GSK3B phosphorylation, …

The Art Of A Slugslayer: An Exploration Of The Process Of Extracting Radulae From Lehmannia Valentiana For The Purpose Of Viewing In The Scanning Electron Microscope, Elizabeth Gannon

Mahurin Honors College Capstone Experience/Thesis Projects

A radula is an anatomical structure found exclusively in mollusks that acts as both tongue and teeth in feeding. Its structure has been studied for more than a century, yet published methods for identifying, dissecting, and cleaning radulae for microscopy are almost unintelligible to anyone not already familiar with molluscan anatomy. The purpose of this project was to identify the best method of garden slug radula isolation and present it in a manner that anyone could understand and successfully use.

After identifying the location of the radula in the slug, the easiest means of removal proved to be simply regurgitating …

The Pros Of Changing Trna Identity, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The notion that errors in protein synthesis are universally harmful to the cell has been questioned by findings that suggest such mistakes may sometimes be beneficial. However, how often these beneficial mistakes arise from programmed changes in gene expression as opposed to reduced accuracy of the translation machinery is still unclear. A new study published in JBC shows that some bacteria have beneficially evolved the ability to mistranslate specific parts of the genetic code, a trait that allows improved antibiotic resistance.

Effects Of Mature Recombinant Gdf9 And Bmp15 On In-Vitro Maturation Of Bovine Oocytes And Subsequent Embryo Development And Effects Of Antioxidants On Blastocyst Re-Expansion Rates, Jamie Thompson

Master's Theses

In-vitro produced embryos (IVP) differ greatly from in-vivo derived embryos (IVD) in gene expression, metabolism, development, and cryotolerance which limit the widespread use of this technology. In-vitro maturation (IVM) is one of the most important components for successful in-vitro embryo development. Growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) have been found to be essential during oocyte maturation and thus female fertility. These proteins are oocyte secreted factors (OSFs) and are produced with pro- and mature protein regions where the pro-regions are thought to aid in protein folding and dimerization where heterodimerization the two proteins has been …

Chemoattractant Distribution In Complex Geometry Impacts The Trajectory Of Clustered Cell Migration, Naghmeh Akhavan

Biology and Medicine Through Mathematics Conference

No abstract provided.

Anillin And Dunk: The Conserved And Non-Conserved Players Regulating Myosin Dynamics In Drosophila Cleavage, Jiayang Chen

Dartmouth College Ph.D Dissertations

Cleavage is a common process during early embryogenesis. Similar to conventional cytokinesis, Drosophila cellularization, a unique form of cleavage, requires precise regulation of non-muscle myosin II ("myosin") at cleavage furrows, where myosin forms an interconnected basal array before reorganizing into individual cytokinetic rings. However, how myosin is regulated through both conserved and cellularization-specific mechanisms during this special form of cytokinesis remains unclear.

In my first project, I investigated the molecular mechanisms by which the cellularization-specific zygotic gene dunk regulates myosin at the basal array. I identified anillin (Scraps in Drosophila), a conserved scaffolding protein in cytokinesis, as the primary …

Understanding The Expression And Role Of Pros-1 In The Male Gonad Of C. Elegans, Jack Bozik

Undergraduate Theses

The gene pros-1 is a transcription factor that is highly expressed within neuronal sheath cells, glial cells, and excretory canal cells. pros-1 plays a role in cell determination of those cell types in the nematode C. elegans, which promotes organismal development. But the degree to which pros-1 presence is important is still not fully understood, because there are many genes involved in development that when mutated or damaged can result in unexpected phenotypes or even total loss of function to a certain developmental mechanism. What makes pros-1 valuable to research is that it is a functional homologue to a …

Consciousness, Evolution, And The Self-Organizing Brain, Karen Seymour

Journal of Conscious Evolution

While evolution is guided by natural selection, it is internally driven by self-organizing processes. The brain encompasses these complementary forces and dynamics of evolution in both its structure and dynamics by embodying a historical record of the factors that have shaped it throughout its evolutionary past, as well as by being shaped by selective parameters in real time. Self-organization is evident in not only the brain’s structure and form, but also in the processes that support consciousness. From the convergence of complex structure and the novelty-generating dynamics of chaos that both characterize the brain arises the experience of explicit consciousness, …

Epidermal Threads Reveal The Origin Of Hagfish Slime, Yu Zeng, David C. Plachetzki, Kristen Nieders, Hannah Campbell, Marissa Cartee, M. Sabrina Pankey, Kennedy Guillen, Douglas Fudge

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

When attacked, hagfishes produce a soft, fibrous defensive slime within a fraction of a second by ejecting mucus and threads into seawater. The rapid setup and remarkable expansion of the slime make it a highly effective and unique form of defense. How this biomaterial evolved is unknown, although circumstantial evidence points to the epidermis as the origin of the thread- and mucus-producing cells in the slime glands. Here, we describe large intracellular threads within a putatively homologous cell type from hagfish epidermis. These epidermal threads averaged ~2 mm in length and ~0.5 μm in diameter. The entire hagfish body is …

Methylene Blue Inhibits Cromakalim-Activated K+ Currents In Follicle-Enclosed Oocytes, Dmytro Isaev, Keun-Hang Susan Yang, Georg Petroianu, Dietrich Ernst Lorke, Murat Oz

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The effects of methylene blue (MB) on cromakalim-induced K⁺ currents were investigated in follicle-enclosed Xenopus oocytes. In concentrations ranging from 3–300 μM, MB inhibited K⁺ currents (IC₅₀: 22.4 μM) activated by cromakalim, which activates K_ATP channels. MB inhibited cromakalim-activated K⁺ currents in a noncompetitive and voltage-independent manner. The respective EC₅₀ and slope values for cromakalim-activation of K⁺ currents were 194 ± 21 µM and 0.91 for controls, and 206 ± 24 µM and 0.87 in the presence of 30 μM MB. The inhibition of cromakalim-induced K⁺ currents by MB was not …

Tgif1 Physiological Levels Limit Β-Cell Distress And Neonatal Diabetes, Creighton J. Friend

Theses and Dissertations

TGIF1 belongs to the superfamily of homeodomain proteins, which regulate a wide variety of biological functions, including cell stemness and specification of cell fate during early development. Perhaps surprisingly, we found that enforced expression in pancreatic progenitor cells during embryogenesis resulted in severe diabetes, hinting at the possibility that TGIF1 might regulate pancreas development. Subsequent genetic experiments targeting β-cells showed that TGIF1 affected β-cell function and homeostasis. Transcriptomic analysis revealed that TGIF1 expression inhibits the expression of essential components of UPR signaling, underscoring a potential mechanism in which TGIF1 disrupts protein folding and secretion. Congruently, TGIF1 expression led to a …

Characterizing Cellular Injury And Inflammation With Aldob-/-Mouse Model Of Mafld, Andy Rashid

All Master's Theses

Metabolic-associated fatty liver disease (MAFLD) affects 1 in 3 people in the US and is a healthcare burden on the order of billions of dollars. MAFLD is characterized by pathological lipid accumulation in the liver, excess production of triglycerides and cholesterol, and export of LDL particles that raise serum lipid levels. These metabolic perturbations can lead to the development of liver fibrosis, chronic inflammation, and insulin resistance. Diagnosing MAFLD prior to fibrosis is crucial for successful intervention and prevention of advanced liver disease and other metabolic complications. Fructose-1Phospahte (F1P) accumulation from fructose overconsumption can drive hepatic lipogenesis and MAFLD progression. …

Conserved Novel Interactions Between Post-Replicative Repair And Mismatch Repair Proteins Have Differential Effects On Dna Repair Pathways, Anna K. Miller

Theses and Dissertations--Toxicology and Cancer Biology

DNA mismatch repair (MMR) is the DNA repair mechanism that repairs base-base mispairs and small insertions and deletions remaining after replication. MMR is also required for apoptosis after certain types of exogenous DNA damage that result in damage-associated mispairs. The basic MMR mechanism is well understood; however, proteins associated with MMR continue to be identified. The roles of these interacting proteins in MMR are largely unknown. We have identified the yeast protein Rad5 as a novel interactor of the critical MMR proteins Msh2 and Mlh1. Rad5 is a DNA helicase and E3 ubiquitin ligase involved in post-replicative repair. However, to …

Cul3 Negatively Regulates Nlrp12-Mediated Inhibition Of The Canonical Nf-Κb Signaling Pathway, Inyeong Lee

Graduate Theses/Dissertations

Nod-like receptor family pyrin domain-containing protein 12 (NLRP12) is mainly known for its inhibitory function on NF-κB signaling in innate immune cells, and more recently, for its ability to regulate chemokine signaling and ubiquitination of the immune receptor RIG-I. Through a yeast 2-hybrid screen, the Lupfer lab previously discovered that NLRP12 interacts with other ubiquitin-associated proteins including Cullin 3 (CUL3) and RING finger protein 2 (RNF2). This research was conducted to mainly investigate the interaction between NLRP12 and CUL3 in human cells and examine the role in regulating NF-κB signaling. Previously, co-immunoprecipitation, followed by western blot analysis, and confocal microscopy …

Therapies For Mitochondrial Disorders, Kayli Sousa Smyth, Anne Mulvihill

SURE Journal: Science Undergraduate Research Experience Journal

Mitochondria are cytoplasmic, double-membrane organelles that synthesise adenosine triphosphate (ATP). Mitochondria contain their own genome, mitochondrial DNA (mtDNA), which is maternally inherited from the oocyte. Mitochondrial proteins are encoded by either nuclear DNA (nDNA) or mtDNA, and both code for proteins forming the mitochondrial oxidative phosphorylation (OXPHOS) complexes of the respiratory chain. These complexes form a chain that allows the passage of electrons down the electron transport chain (ETC) through a proton motive force, creating ATP from adenosine diphosphate (ADP). This study aims to explore current and prospective therapies for mitochondrial disorders (MTDS). MTDS are clinical syndromes coupled with abnormalities …

The Effects Of Deleting Lrb E3 Ligase Region 2 On Red Light Responses In Arabidopsis Thaliana, Sabina Liskey

Masters Theses

The ability of plants to absorb light through photoreceptors is essential for successful plant development. Phytochromes are important plant photoreceptors that detect and absorb red and far-red light and must function properly for plant survival. The Light Response BTB proteins (LRB) play an important role in a plant’s response to red light by degrading phytochrome B (PhyB) via the ubiquitin proteasome system (UPS). Although there has been a successful investigation into understanding the function of the LRBs, the function of a few regions within LRB proteins remains unknown, including a portion located on the N-terminal end of the protein, termed …

Clustered Protocadherins Ubiquitination And Phosphorylation Regulates Surface Expression, Albert Ptashnik

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) are a family of 60 adhesion-like molecules forming a neural barcode. In vertebrate neurons, 60 Pcdhs are coded by a large gene cluster. Numerous axons in the cluster are coding for the different extracellular, transmembrane, variable portion of the cytoplasmic and constant cytoplasmic domains where their expression is controlled epigenetically. These proteins mediate interactions between axons, dendrites, and glial cells during neural development. Yet, Pcdhs are not strictly adhesion molecules. In the amacrine cells of the retina, Pcdhs promote avoidance of the same cell dendrites, where in the cortex Pcdhs promote interactions between dendrites and astrocytes. In …

The Novel Role Of Dnmbp In Kidney Development, Brandy Walker

Dissertations and Theses (Open Access)

Congenital anomalies of the kidney and urinary tract (CAKUT) accounts for nearly one-fourth of all birth defects and more than 40% of pediatric end-stage renal disease, yet only 10-20% of CAKUT cases have a known monogenetic cause. Human kidneys are composed of up to a million epithelial tubules called nephrons. Disruption of nephron development is one of the many congenital anomalies that cause CAKUT, often resulting in chronic or end-stage renal disease which requires transplant. During nephron epithelialization, the formation of stable cadherin-mediated adhesion junctions is essential for maintaining cell-cell contacts. To understand the cell behaviors underlying abnormalities in renal …

Hyper Stable Variants Of Fgf-1-Fgf-2 Dimer, Madison Shields Mcclanahan

Chemistry & Biochemistry Undergraduate Honors Theses

Fibroblast Growth Factors (FGFs), including FGF-1 and FGF-2, are proteins that play a crucial role in cell proliferation, cell differentiation, cell migration, and tissue repair. FGF-1 and FGF-2 are useful in accelerating the healing process in the human body; however, these proteins are naturally thermally unstable, resulting in a relatively low half-life in vivo. 1,8 In efforts to improve the stability of this protein, FGF-1 and FGF-2 proteins are engineered by combining the amino acid sequences of the two proteins to form a heterodimer and obtain novel properties. These two FGF variants are chosen for their specific wound healing capabilities. …

Functional Role Of Ppal And Potential For Moss In Industrial Applications., Susana Perez Martinez

Electronic Theses and Dissertations

This dissertation is an examination and characterization of the functional roles of PPAL. PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) is a recently discovered gene. PPAL homologs are present in all plants and many animals, where its function is largely unknown. It is possible that PPAL could participate in prenylation processes since it shares similarity to the α subunits of known prenylation enzymes. Prenylation is a post-translational modification of proteins that involves the addition of a lipid moiety to proteins to facilitate membrane targeting and association and promote protein-protein interactions. Prenylation has important roles in plant growth and development, including …