Cell Biology Commons^™

Prenatal Androgen Exposure Reduces Ovarian Function, Marlee Weets

All Master's Theses

Polycystic ovary syndrome (PCOS) is the most common reproductive and endocrine disorder, being the leading cause of infertility for females of reproductive age. The etiology of PCOS is not fully known, although it is hypothesized that there is a genetic, epigenetic, and environmental component to the disease. One of the environmental influences that can cause an abnormal reproductive phenotype similar to PCOS is prenatal exposure to excess androgens (male sex hormones). Previous studies have shown that prenatal exposure to androgens in mice can cause a PCOS-like ovarian phenotype similar to people with PCOS. To examine how prenatal androgen exposure causes …

Pai-1 As A Critical Factor In The Resolution Of Sepsis And Acute Kidney Injury In Old Age, Maria E. C. Bruno, Sujata Mukherjee, Jamie L. Sturgill, Virgilius Cornea, Peng Yeh, Gregory S. Hawk, Hiroshi Saito, Marlene E. Starr

Markey Cancer Center Faculty Publications

Elevated plasma levels of plasminogen activator inhibitor type 1 (PAI-1) are documented in patients with sepsis and levels positively correlate with disease severity and mortality. Our prior work demonstrated that PAI-1 in plasma is positively associated with acute kidney injury (AKI) in septic patients and mice. The objective of this study was to determine if PAI-1 is causally related to AKI and worse sepsis outcomes using a clinically-relevant and age-appropriate murine model of sepsis. Sepsis was induced by cecal slurry (CS)-injection to wild-type (WT, C57BL/6) and PAI-1 knockout (KO) mice at young (5–9 months) and old (18–22 months) age. Survival …

Examining Pi3k-Signaling-Dependent Regulation Of Lens Organelle Free Zone Formation Via Immunolocalization And Immunoblotting In Chick Embryos, Rifah Gheyas, A. Sue Menko

Computational Medicine Center Faculty Papers

The elimination of lens organelles during development, required for mature lens function, is an autophagy-dependent mechanism induced through suppression of PI3K signaling. Here, we present a protocol for investigating the signaling pathways responsible for induction of the formation of this lens organelle free zone. We describe steps for preparation of lens organ culture and use of signaling pathway inhibitors. We then detail procedures for analyzing their impact using both confocal microscopy imaging of immunolabeled lens cryosections and immunoblot approaches. For complete details on the use and execution of this protocol, please refer to Gheyas et al. (2022).

Canine Testes Thin Sections Culture​, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Canine Testes Thin Sections Culture, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Mob Family Proteins And Tricornered Kinase Are Required To Form Dorsal Appendages Of The Drosophila Eggshell, Keala H. D. Watson

UNLV Theses, Dissertations, Professional Papers, and Capstones

To understand how complex tissues are formed, we need to understand how cells communicate with other cells to build structures. In Drosophila melanogaster, epithelial cells form tubular structures to shape the dorsal appendages on the eggshells. One signaling pathway needed for this event is the Hippo-like kinase intracellular pathway. I focus on two key components in this pathway: the NDR kinase Tricornered (Trc) and Mob proteins. In eukaryotes, Mob proteins are known to interact with NDR kinases to promote their activation. The Hippo- like pathway involves the NDR kinase Trc; however, the specific Mob protein(s) that interact with Trc …

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 Regulatory Context And Mechanism Of Hlh-25 Mediated Transcriptional Repression, Dagmawi Mamo

Masters Theses, 2020-current

The HES family of transcription factors are primarily repressors of transcription that play critical roles in mammalian embryogenesis by regulating cell differentiation and proliferation. Proper functioning of HES proteins is crucial in humans, as mutations or misexpression of HES1 is associated with lung, pancreas, colon, and other cancers. HES1 may mediate short-range or long-range repression through DNA-binding and or protein-protein interactions with other factors. However, prior genetic studies have not fully elucidated how the context-specific binding of HES1, or its C. elegans ortholog HLH-25, promotes the repression of transcription. Characterization of the cis-regulatory context and mechanism of HLH-25 mediated repression …

Mitochondrial Roles In Developmentally Programmed Heart Disease, Eli John Louwagie

Dissertations and Theses

Offspring of diabetic and obese mothers (ODOM) have greater risks of heart disease at birth and later in life. However, prevention is hindered because underlying mechanisms are poorly understood. Mounting studies in the Developmental Origins of Health and Disease field suggest that mitochondria play key roles in developmentally programmed heart disease similar to the roles they play in cardiomyopathy in adults with diabetes and obesity. However, whether mitochondria are responsible for the short[1]and long-term cardiac disease seen in ODOM remains unknown. Here, we sought to delineate the roles of mitochondria in the hearts of ODOM, determine whether mitochondria are playing …

Examining Transcriptional Regulators During Muscle Development In Drosophila Melanogaster, Chaamy Yapa

Student Theses and Dissertations

In Drosophila melanogaster embryos, a distinct approach to study the transcriptional regulation is to examine the larval somatic muscle development. Transcription factors are essential regulatory proteins that help to control gene expression and respond to signaling pathways and various cues. Today, there are at least twenty transcription factors that have been discovered to contribute to the development of the 30 distinct larval somatic muscles in each abdominal hemisegment of Drosophila melanogaster. Several studies have already been conducted on muscle regulatory transcription factors including midline and apterous. These transcription factors were shown to control the development of muscles through mutant …

Adipocytes And Innate Immunity In Systemic Sclerosis, Nancy Wareing

Dissertations and Theses (Open Access)

Systemic sclerosis (SSc; scleroderma) is a chronic systemic autoimmune and connective tissue disorder characterized by vasculopathy, autoimmune phenomena, and widespread fibrosis. Skin thickening and tightening is the cardinal feature of SSc and is responsible, in part, for the considerable morbidity of this disease. There are currently no targeted treatments for skin manifestations in SSc, primarily due to our fragmented understanding of its pathophysiologic mechanisms. In PART I, we report a previously unappreciated link between aberrant expression of the developmental gene sine oculis homeobox homolog 1 (SIX1) in skin-associated adipocytes in SSc skin and the early loss of dermal white adipose …

Investigation The Plugging Behavior Of Virus Filters, Iman Abdulqader Saab

Graduate Theses and Dissertations

A virus filtration step is integral to the manufacturing of biopharmaceuticals to ensure viral safety. A virus filter is a single-use device that uses a size-based separation process and has a unique structure with minimal defects, so that contaminating virus particles cannot pass through the membrane pores, while therapeutic molecules can. The development of novel antibodies (Abs), including significant increases in product titers, is frequently challenged by virus filter fouling, making a better understanding of the underlying mechanisms essential. This thesis focused investigating of the effect of prefilter types, buffer type and salt content on virus filtration performance. The impact …

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 …

Immunohistochemical Investigation Of Wwp1 Expression During Embryonic Heart Development And Its Implications For Cardiac Aging, Savannah L. Bowers

Senior Theses

Cardiovascular disease is the leading cause of mortality globally, with the aging population being most vulnerable. Cardiomyocytes and cardiac fibroblasts mediate pathophysiological changes of cardiac aging including interstitial fibrosis, left ventricular hypertrophy, lethal arrhythmias, and eventual culmination in heart failure. Interestingly, subclinical congenital heart disease and hypertrophic cardiomyopathy, originating in embryonic development, induce accelerated cardiac aging. The diverse developmental origins of cardiac fibroblasts suggest that perturbations in gene expression within this heterogeneous cell population during embryonic heart development have significant consequences for cardiac aging. Previous studies implicate the E3 ubiquitin ligase WWP1, a post-translational regulatory protein, in accelerated cardiac aging. …

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 …

Comparison Of In-Vitro 3d Human Embryoids With Current Models For Gastrulation, Jin Park

McKelvey School of Engineering Graduate Student Theses & Dissertations

Gastrulation is an early morphogenetic process that is conserved across most metazoans and lays out the future body plan through the formation and shaping of the three germ layers: endoderm, mesoderm, and ectoderm. Despite its importance, not much is known about the events surrounding human gastrulation that occurs in utero due to ethical and technical limitations on studying human embryos. Therefore, many researchers have devised protocols for creating in vitro models of gastrulation using embryonic stem cells. Initially starting with mouse embryonic stem cells, the field of in vitro embryo models has advanced rapidly, with protocols using human embryonic stem …

Quantification Of Nuclear Dynamics During Epithelial Remodeling, Noah De Leeuw

Electronic Theses and Dissertations

The morphogenesis of developing tissues is contingent on an extensive array of rearrangements in cellular shape, position and identity at large and small scales. One commonly used process to reshape tissues is the cell intercalation-driven elongation of a tissue in a common axis, in which rows of epithelial cells undergo oriented intercalation in a directional fashion. In most models of intercalation, cells are treated as homogeneous objects directed in their shape changes by cortical forces localized along cell-cell interfaces or tricellular junctions. However, less attention has been paid to how inhomogeneities in mechanical resistance of their own internal structures affects …

Analysis Of A Cathepsin Protease In Normal Development And Tumor Metastasis In Drosophila Melanogaster, Lindsey Fannin

Mahurin Honors College Capstone Experience/Thesis Projects

Cysteine cathepsins are an important class of fifteen proteases with involvement in normal development and tumor progression. To better understand their contribution to these processes, the cathepsin L protease in Drosophila melanogaster was studied. In part one of this project, the role of this cathepsin in the normal development of Drosophila wings was analyzed. The GAL4/UAS-system and RNAi were used to downregulate this cathepsin in various regions of the wing and progeny were inspected for phenotypic irregularities. An abnormal phenotype of curved wings was found and hypothesized to be a result of apoptosis. Further experimentation will be required to prove …

Exploring The Molecular Basis Of Touch: A Comparative Analysis Of Gene Expression In Sensory Corpuscle-Rich And Corpuscle-Poor Skin Regions In The Duck, Thomas Hart

Theses and Dissertations--Biology

Cutaneous touch is facilitated by discrete cellular complexes composed of non-neuronal cells associated with mechanoreceptor neuron endings. The non-neuronal cells of these cutaneous end organ complexes (CEOCs) are believed to contribute to touch, but their role in touch sensation remains unclear. To better understand the function of CEOC cells, we sought to characterize the transcriptional profile of CEOC-rich tissue and identify genes expressed in CEOC cells. Bill skin of the tactile foraging Pekin duck (Anas platyrhynchos) is dense with CEOCs, specifically the avian analogs of mammalian Pacinian and Meissner corpuscles, while corpuscles in duck foot skin are scarce. Using RNA …

Ros And Sfk Signaling Is Required For Development Of Hematopoietic Stem Cells In Zebrafish, Bradley Williams, Erich Damm

Undergraduate Research Posters

ROS and SFK signaling is required for development of hematopoietic stem cells in zebrafish

Bradley Williams and Erich Damm

Background

Hematopoiesis is the process in which the myriad of mature blood cell types, including erythrocytes and leukocytes, develop from hematopoietic stem cells (HSCs) throughout the life of an organism. In vertebrates, HSCs originate from endothelial cells lining the floor of the dorsal aorta. This process is referred to as the endothelial to hematopoietic transition and is likely controlled in part by molecular signals from neighboring cells. Investigation into the molecular signaling mechanisms controlling the development of HSCs is critical to …

Dysregulated Polycomb Repressive Complex 2 Contributes To Chronic Obstructive Pulmonary Disease By Rewiring Stem Cell Fate, Aria Byrd, Xufeng Qu, Alexsandr Lukyanchuk, Jinpeng Liu, Fan Chen, Kassandra J. Naughton, Tanner Ducote, Xiulong Song, Hannah Bowman, Yanming Zhao, Abigail R Edgin, Chi Wang, Jinze Liu, Christine Fillmore Brainson

Markey Cancer Center Faculty Publications

Aberrant lung cell differentiation is a hallmark of many lung diseases including chronic obstructive pulmonary disease (COPD). The EZH2-containing Polycomb Repressive Complex 2 (PRC2) regulates embryonic lung stem cell fate, but its role in adult lung is obscure. Histological analysis of patient tissues revealed that loss of PRC2 activity was correlated with aberrant bronchiolar cell differentiation in COPD lung. Histological and single-cell RNA-sequencing analyses showed that loss of EZH2 in mouse lung organoids led to lowered self- renewal capability, increased squamous morphological development, and marked shifts in progenitor cell populations. Evaluation of in vivo models revealed that heterozygosity of Ezh2 …

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 …

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 …

Regulation Of Tissue Mechanics And Adherens Junctions By Small Gtpase Rhoa During Drosophila Embryogenesis, Hanqing Guo

Dartmouth College Ph.D Dissertations

Actomyosin contractility plays an important role at both the cell and tissue level during developments. In this study, we developed an optogenetic tool that can acutely inhibit actomyosin contractility by targeting its main activator Rho1. This optogenetic tool can achieve myosin inhibition within one minute and thus enable further dissection of actomyosin function in development. In my first two projects, I used Drosophila mesoderm invagination (also known as ventral furrow formation) as a model to study epithelial folding, a fundamental mechanism for constructing complex 3D tissues. Apical constriction mediated by actomyosin contractility is a common mechanism for epithelial folding. However, …

Determination Of The Functional Role Of Rab-Ggt In Physcomitrium Patens., Hyun Jin Jung

Electronic Theses and Dissertations

Protein prenylation, a common lipid post-translational modification, is required for growth and development in eukaryotes. Rab geranylgeranylation involves the addition of one or two 20-carbon geranylgeranyl moieties to Rab-GTPase target proteins, which regulate intracellular vesicle trafficking. The reaction is carried out by heterodimeric Rab geranylgeranyltransferase (Rab-GGT), which is composed of two associated α- and β-subunits, with the assistance of an additional protein called Rab escort protein (REP). Loss of function of the Rab-GGT α subunit RGTA1 has not been reported in any plant. While knockout of either of the two β subunits RGTB1 or RGTB2 results 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 …

The Effect Of Fibrodysplasia Ossificans Progressiva On The Tongue, Amy Backal, Amanda Harrop, David J. Goldhamer Dr.

Honors Scholar Theses

FOP is a rare genetic disorder in which skeletal muscle and associated connective tissue progressively turn to bone through a process called heterotopic ossification (HO). The extra skeletal bone growth is cumulative, eventually trapping patients in a second skeleton that eventually leads to death by asphyxiation. The FOP mutation is autosomal dominant that can be inherited or acquired sporadically. Unfortunately, FOP is currently incurable with no therapeutic options to inhibit bone growth or reduce existing bone nodules. My project intends to further our understanding of the cellular mechanisms of the disease within the tongue muscle. A population of cells known …

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. …

Role Of H3k4 Methylation In Myogenesis, Regeneration, And Muscle Disease / Narrative Competence And Cognitive Mapping As A Culturally Sustaining Pedagogy In The Education Of Emergent Bilinguals, Hannah Emily Shippas

Legacy Theses & Dissertations (2009 - 2024)

Muscles are a crucial part of an organism’s wellbeing, as defects in distinct types of muscles can be lethal. Our voluntary muscles, skeletal muscles, go through distinct regeneration phases before reaching maturity. With its own pool of stem cells, muscles have a large potential for regeneration. This potential has led scientists into looking closely at the steps that lead a muscle stem cell into muscle fiber, also known as myogenesis. As a muscle cell moves through myogenesis, genes are led to be turned on/off with different epigenetic mechanisms, one being histone modifications. A methylation modification on the 4th Lysine on …

Structural Formation And Functionality Of The Spoiie Protein In Clostridium Difficile, Rachel Siebenmorgen

Biological Sciences Undergraduate Honors Theses

My research efforts were directed toward the structure and functionality of a protein, designated SpoIIE [11], which previously has been shown to regulate C. difficile peptide utilization in addition to sporulation and toxin release. The SpoIIE protein is found in all spore-forming gram-positive bacteria and is a crucial component in activation of transcription factors and septum formation thus affecting the regulation and timing of spore development [11,12]. A truncated form of the SpoIIE protein named SpoIIE∆TM was used in an effort to determine the structure of an important but uncharacterized linker domain of the protein. If the structure and specific …