Developmental Biology Commons^™

Nutrient Scarcity And Cellular Cooperation In A Clonal Hydroid, Weam S. El Rahmany

Graduate Research Theses & Dissertations

Biological complexity forms when lower-level units (e.g., genes, cells, organisms) cooperatively band together. This complexity may be exemplified by multicellularity, the cooperation between the cells of the same species, or symbiosis, cooperation between the cells of different species. This cooperation is under continual threat, as defection, the opposite of cooperation, is favored by default by lower-level units (i.e., cells). Animal cancers may be the most well-known phenomena that exemplify the concept of cellular defection. Cancer cells have been shown to feature morphological and metabolic traits, developed through differential gene expression or mutations, that favor their growth at the cost of …

Getting To The Root Cause: The Genetic Underpinnings Of Root System Architecture And Rhizodeposition In Sorghum, Farren Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

Plants are some of the most diverse organisms on earth, consisting of more than 350,000 different species. To understand the underlying processes that contributed to plant diversification, it is fundamental to identify the genetic and genomic components that facilitated various adaptations over evolutionary history. Most studies to date have focused on the underlying controls of above-ground traits such as grain and vegetation; however, little is known about the “hidden half” of plants. Root systems comprise half of the total plant structure and provide vital functions such as anchorage, resource acquisition, and storage of energy reserves. The execution of these key …

Neuronal Migration In Developmental Hyperserotonmia: Assessment Of Vesicular Glutamate In The Raphe Nuclei, Trey M. Shupp

Graduate Theses/Dissertations

The neurotransmitter serotonin is involved in the early development of the central nervous system and the organization of neurons throughout the cerebral cortex and cerebellum. It is proposed that serotonin indirectly interacts with cells in the marginal zone of the cerebral cortex known as Cajal-Retizus (CR) cells. These cells secrete the extracellular matrix protein reelin, which is known for its role in neuronal organization and migration during early neural development. It has been observed that low levels of serotonin are associated with similarly low levels of reelin during development and have been reported to result in disorganization of neurons in …

Bone Morphogenetic Protein Signaling Requirement In Centripetal Migration In Drosophila Melanogaster Oogenesis, Sheila Mosallaei

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cells interact with each other via signals to coordinate migration for proper tissue development and maintenance, immunity and tissue repair. Signals regulate migration via changes to cytoskeletal components or transcriptional regulation. Here, I used Drosophila melanogaster to investigate whether and how a transcriptional signal, Bone Morphogenetic Protein signaling, drives a cell migration, centripetal migration. The migrating cells, centripetal follicle cells, consist of two subsets of cells, “leading” and “following” centripetal follicle cells, that although adjacent to each other, migrate differently. The differences in modes of migration correlate to differential gene expression in the centripetal follicle cells. The leading centripetal follicle …

Creating A Protein Chimera To Study Regulation Of Muscle Diversity, Shannon Scarboro

Symposium of Student Scholars

Creating a protein chimera to study regulation of muscle diversity.

Body muscles are made of many individual super-cells, called muscle fibers, that have distinct properties and determine every individual’s strength and endurance. Initially all muscle fibers have identical characteristics, but become differentiated into specific types in adults. The mechanism of such transition is not well understood, despite its obvious importance for shaping human physicality.

Remarkable conservation of the muscle tissue enables us to use fruit flies to study the mechanisms of muscle fiber diversity. We hypothesized that the transcription factor Mef2 acts as a molecular switch that activates structural genes …

216— Loss Of Function Mutation For Tp53 Does Not Rescue The Chaf1bNt2 Small-Eye Phenotype In Danio Rerio, Alex Parks

GREAT Day Posters

In Zebrafish, the chromosome assembly factor 1b (chaf1b) gene is in part responsible for the development of the eye. In homozygous chaf1bt24412 mutants retinal cell death is promoted through cell-death promoting activity of the gene, tumor suppressor protein p53 (tp53), resulting in a small-eye phenotype. Another allele chaf1bnt2, was found to also result in the small-eye phenotype when in a homozygous state. We found that knockdown of Tp53 protein via morpholino antisense oligonucleotide injection of 1-2 cell stage embryos failed to rescue retinal cell death of chaf1bnt2 homozygous mutants as detected by TUNEL labeling. Because morpholinos may fail to fully …

Characterization Of The Whale Shark (Rhincodon Typus) Melanocortin-2 Receptor, Brianne Hoglin

Electronic Theses and Dissertations

Among bony vertebrates, the melanocortin-2 receptor ortholog is unique among the family of five melanocortin receptors on the basis that it is dependent on its accessory protein, MRAP1, for trafficking and activation, and is selective for activation by ACTH alone. Previous studies on the MC2R orthologs of select cartilaginous fish, the elephant shark (Callorhinchus milii) and the red stingray (Dasyatis akajei), revealed divergent traits in a less obligatory relationship on MRAP1 and its ability to be activated by ACTH or the MSH-sized peptides. However, observed traits were not consistent between these two cartilaginous fish species, posing …

Rab35 Centered Membrane Trafficking Pathway Directs Apical Constriction During Drosophila Gastrulation, Hui Miao

Electronic Theses and Dissertations

Force generation in epithelial tissues is often pulsatile, with actomyosin networks generating high-tension contractile forces at the cell cortex before cyclically disassembling. This pulsed nature of cytoskeletal forces implies that there must be cellular processes to extract unidirectional changes that drive processive transformations in cell shape. During Drosophila melanogastergastrulation, the invagination of the prospective mesoderm is driven by the pulsed constriction of apical surfaces. Here, we address the mechanisms by which the irreversibility of pulsed events is achieved while also permitting uniform epithelial behaviors to emerge. We use MSD-based analyses to identify contractile steps and find that when a …

Mesenchymal Stem Cells And Their Extracellular Vesicles: A Potential Game Changer For The Covid-19 Crisis, Dina H. Kassem, Mohamed M. Kamal

Pharmacy

Corona virus disease 2019 (COVID-19) is a global public health crisis. The high infectivity of the disease even from non-symptomatic infected patients, together with the lack of a definitive cure or preventive measures are all responsible for disease outbreak. The severity of COVID-19 seems to be mostly dependent on the patients’ own immune response. The over-activation of the immune system in an attempt to kill the virus, can cause a “cytokine storm” which in turn can induce acute respiratory distress syndrome (ARDS), as well as multi-organ damage, and ultimately may lead to death. Thus, harnessing the immunomodulatory properties of mesenchymal …

Artificial Intron Technology To Generate Conditional Knock-Out Mice, Amber N. Thomas-Gordon

Dissertations and Theses (Open Access)

Genetic engineering has been re-shaped by the invention of new tools in modern biotechnology in a way that offers precision and efficiency in modifying the genome at a single nucleotide level and/or allowing precise control of gene expression. Such gene manipulation brings about significant findings and revelations in comprehending more about embryonic development, cellular and physiological functions, and disease pathology. Current methods used to produce conditional knockouts have limitations on conditional allele placement and modification varies among genes in different organisms. Thus, a system for generating conditional alleles with fidelity remains a challenge. My goal was to examine an approach …

Insights Into Desiccation Tolerance: Properties Of Late Embryogenesis Abundant Proteins From Embryos Of Artemia Franciscana, Blase Matthew Leblanc

LSU Doctoral Dissertations

LEA proteins are a family of intrinsically disordered proteins that are expressed in various life stages of anhydrobiotic organisms and have been strongly associated with survival during water stress. The brine shrimp Artemia franciscana is the only known anhydrobiotic animal that expresses LEA proteins from Groups 1, 3, and 6. Here, I report that AfrLEA6, a novel Group 6 LEA protein, is most highly expressed in embryos during diapause and decreases throughout pre-emergence development. Notably, there is an acute drop in expression upon termination of the diapause state and the titer of AfrLEA6 during diapause is 10-fold lower than values …

Probing The Limits Of Singular Gene Expression Through The Activity Of High Representation Odorant Receptor Transgenes, Eugene Lempert

Dissertations, Theses, and Capstone Projects

Singular gene expression is a common phenomenon in biology, making its appearance in immunoglobulin selection, protocadherin expression, X chromosome-inactivation, random monoallelic expression, and olfactory receptor choice. Singularity involves an activation and a feedback step. The mechanisms of singular gene choice have some capacity to integrate additional member genes while still maintaining singularity, but will activate an additional member if an earlier choice was incapable of triggering the feedback step. Odorant Receptor (OR) genes are substantially divergent from each other in terms of coding sequence, promoter structure, and genomic locus, all of which plays a role in how many Olfactory Sensory …

Dictyostelium Discoideum Protein Kinase C-Orthologue Pkca Regulates The Actin Cytoskeleton Through Interaction With Phospholipase D And P21-Activated Kinase, Sean Singh

Dissertations, Theses, and Capstone Projects

Proper regulation of the actin cytoskeleton is crucial to many cellular processes. Many of these processes are regulated by extracellular signaling cues, which direct changes in the actin cytoskeleton, resulting in changes to cellular morphology, and directed motility. The social amoeba, Dictyostelium discoideum, is used as a simple model system to study the translation of extracellular signals to the actin cytoskeleton. When starved, these unicellular amoebae undergo a multicellular developmental process characterized by a tightly regulated sequence of signaling events. This results in chemotaxis and formation of a multicellular aggregate, and ultimately cell differentiation and the formation of a fruiting …

Serpinb1 Effects On Human Pancreatic Ductal Cells, Praneeth Goli

College of Arts & Sciences Senior Theses

Rebuilding or expanding the body’s ability to regulate blood glucose levels by restoring or increasing the body’s ability to produce insulin, long-term, would be a major advancement in diabetes (type-1 and type-2) treatment and could serve as a potential cure [1]. Therefore, the holy grail of diabetes treatment and cure research is to regenerate or increase the insulin producing cells in diabetic individuals (type-1 and type-2) [1, 2]. SerpinB1 has been implicated as a biomolecular signal that stimulates an increase in insulin cell mass in murine and zebrafish models that exhibit physiologically normal compensatory islet hyperplasia. In humans, SerpinB1 is …

Cellular And Developmental Insights Into The Early Evolution Of Muscle, Jeffrey J. Colgren

Electronic Theses and Dissertations

Whereas a great deal has been learned about the molecular underpinnings of morphological evolution in animals, much less is known about the origin of novel cell and tissue types. During the time in which the earliest animal lineages were diversifying, fundamental cell and tissue types, such as muscles, arose. Sponges are one of two animal lineages that lack muscles, yet they undergo coordinated full body contractions. Whereas the signaling processes have been studied, the physical mechanisms of contraction are completely uncharacterized. The main purpose of this work is to understand the primary contractile tissue of the sponge Ephydatia muelleri, …

Launching The Next Generation : Transcriptional Regulation During Oogenesis, Alicia K. Mccarthy

Legacy Theses & Dissertations (2009 - 2024)

Germ cells give rise to gametes and link generations by passing genetic information from parent to offspring. Gametes arise from, in many sexually reproducing organisms, germline stem cells (GSCs) which are set aside early during development. GSCs have an amazing capacity to undergo self-renewal to give rise to a pool of undifferentiated cells, while also differentiating to generate specialized germ cells such as haploid gametes. Upon female GSC differentiation, mitotically dividing germ cells can initiate meiosis, and mature within a follicle. During maturation, the specified oocyte is provided with a trust fund of RNAs and proteins for the next generation …

Therapeutic Efficacy Of Umbilical Cordderived Stem Cells For Diabetes Mellitus: A Meta-Analysis Study, Dina H. Kassem, Mohamed M. Kamal

Pharmacy

Background: Stem cell therapy provides great hope for patients with diabetes mellitus (DM). DM is a seriously alarming metabolic disease characterized by hyperglycemia and β cell dysfunction. Efficient novel therapeutic modalities to treat DM are indeed warranted. Stem cells (SC) derived from the umbilical cord specifically provide several advantages and unique characteristics being a readily available non-invasive source, with an additional credit for their banking potential. This meta-analysis study aims to provide a focused assessment for therapeutic efficacy of umbilical cord (UC)-derived SC-transplantation, namely Wharton’s jelly mesenchymal stem cells (WJMSCs) and umbilical cord blood (UCB) for DM. Methods: The clinical …

Non-Invasive Method For Leptin Supplementation In Zebrafish (Danio Rerio), Regan Mcnamara

Williams Honors College, Honors Research Projects

I tested the hypothesis that recombinant leptin protein can be introduced to zebrafish in vivo through non-invasive soaking in a solution containing the protein. One way to study various molecules’ effects in vivo is through intraperitoneal or intracerebroventricular injections during the embryonic or larval stage, which is invasive, difficult to administer, and can have a high mortality rate. 48 hours post fertilization (hpf) zebrafish were soaked in a His-tagged recombinant leptin protein solution at 10 nM and 100 nM concentrations (produced by Genscript). After soaking, zebrafish larvae were washed extensively to remove all recombinant protein on their exterior before homogenization. …

Role Of Ciliary Proteins Adp Ribosylation Factor Like Gtpase 13b (Arl13b) And Bardet-Biedl Syndrome-8 (Bbs8) In Photoreceptor Outer Segment Morphogenesis, Maintenance, And Viability, Tanya L. Dilan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photoreceptor neurons are modified primary cilia with an extended ciliary compartment known as the outer segment (OS). The mechanisms behind the elaboration of photoreceptor cilia, OS morphogenesis, and maintenance remain poorly understood. In this work, we focused on dissecting the role of two ciliary proteins, the small GTPase ADP-ribosylation factor-like GTPase 13B (ARL13B) and Bardet-Biedl Syndrome-8 (BBS8) in the context of photoreceptor biology. Both BBS8 and ARL13B are linked to defects in ciliogenesis (cilia development) and Retinitis Pigmentosa (vision loss). ARL13B is implicated in regulating ciliary length, and BBS8 is part of the Bardet-Biedl Syndrome complex (BBSome); the BBSome is …

Recruitment Of Polycomb-Group Proteins At Giant In Drosophila Embryos, Elnaz Ghotbi Ravandi

Biological Sciences Theses and Dissertations

Polycomb Group (PcG) proteins are evolutionarily conserved epigenetic transcriptional regulators that maintain the transcriptional repression of silenced genes. PcG mediated silencing is divided into two phases: initiation and maintenance. During the initiation phase, PcG proteins initially recognize and bind to their target genes. Once PcG proteins are recruited to their target genes, they can maintain transcriptional repression through an unlimited number of cell cycles. Most studies on PcG proteins have been focused on the maintenance phase of PcG silencing, and the molecular mechanisms by which PcG proteins are initially recruited to their target genes remained unknown. Two models have been …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

The Influence Of Mir-322 On Skeletal Muscle Differentiation, Miles Alexander Soyer

Legacy Theses & Dissertations (2009 - 2024)

Skeletal muscle plays a crucial role in coordinating voluntary movement and accounts for nearly 50% of total body mass. Dysregulation in skeletal muscle development is known to cause muscle degenerative diseases including the devastating Duchenne Muscular Dystrophy (DMD). The majority of the biological studies investigating muscle development were based on myogenic transcription factors and signaling molecules including: Pax7, Myf5, MyoD, WNT, TGF-β and BMP. After the discovery of non-coding RNAs including microRNAs, it was postulated that these molecules could regulate gene expression and thus affect differentiation and development. MicroRNAs are small non-coding RNAs (~17-25 nucleotides) that regulate gene expression negatively …

Understanding The Molecular And Cellular Functions Of Odd-Skipped Related 1 In Outflow Tract Development, Menglan Xiang

Theses and Dissertations

The cardiac outflow tract (OFT) is a transient conduit that connects the embryonic heart chambers to the vascular network. Transcription factor Osr1 promotes the proliferation and cell cycle progression of second heart field (SHF), an essential cell population that contribute to the developing OFT. In this study, we investigated the role of Osr1 in OFT development on cellular and molecular levels using a systems biology approach. We observed OFT rotation and elongation defects, as well as double-outlet right ventricle and overriding aorta as a result of SHF-specific deletion of Osr1. Using genetic inducible fate mapping, we showed that Osr1-expressing SHF …

Knocking Out A Negative Regulator Of Hedgehog Signaling Blocks Differentiation Of Cells Into Neurons, Danielle Margaret Spice, Gregory M. Kelly Ph.D.

Western Research Forum

Hedgehog (Hh) signaling, one of many different protein signaling pathways found in mammals, is vital in many stage of neural development. A major negative regulator of Hh signaling is a protein known as Suppressor of Fused (SUFU), which acts to sequester the full length Gli transcription factors, proteins that can turn genes on and off, in the cytoplasm or facilitates its conversion to a repressive form. The P19 embryonal carcinoma cell line is a model of hind-brain neuronal differentiation and the involvement of Hh signaling, in particular the role of SUFU in this process has yet to be explored. We …

Delineation Of Events In Centripetal Migration During Drosophila Oogenesis, Travis Tait Parsons

UNLV Theses, Dissertations, Professional Papers, and Capstones

All multicellular organisms initially start out as a single cell. This cell must use the genetic information encoded in its DNA to multiply in number and build itself into a complex multicellular organism. How this process occurs is the focus of developmental biology, a field that seeks to understand how a combination of genetic information and environmental conditions shape a cell from its beginnings as a zygote all the way to maturity. A fundamental part of this process is the ability of cells to work together in order to build complex tissues and organs. Cells achieve this coordination by using …

Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey

Biology ETDs

Properly executed cell division is crucial to development, maintenance, and longevity of multicellular organisms. Defects in both symmetric and asymmetric divisions can lead to improper developmental patterning, as well as genomic instability, disruption of tissue homeostasis, and cancer. Our research focuses on how regulators orchestrate proper cell divisions. Mushroom Body Defect (Mud) is one such regulator, and here we describe how Mud is regulated via the Hippo signaling pathway kinase Warts (Wts), showing Wts phosphorylates Mud to enhance interaction with the polarity protein Partner of Inscuteable, promoting spindle orientation activity. We next focus on another regulator, Shortstop (Shot), describing a …

Study Of The Effects Of Silver Ions And Silver Nanoparticles On Embryonic Development, Martha Sharisha Johnson

Biomedical Sciences Theses & Dissertations

This dissertation focuses on the study of the toxicity of metal nanoparticles (NPs) and their ions on the development of zebrafish embryos, aiming to understand unique biological effects of NPs and ions, and design new in vivo assays to characterize the toxicity of these metal NPs and metal ions. Currently, the underlying molecular mechanisms of biological effects of nanomaterials are partially understood. Some studies assume that the toxic effects of NPs can be attributed to the release of their ions. We investigate the effects of silver NPs (Ag NPs) and silver ions (Ag+ ions) on the embryonic development of zebrafish …

Investigating The Role Of The Chromosome 19 Microrna Cluster In Human Trophoblast Differentiation And Infantile Hemangioma, Ezinne Francess Mong

USF Tampa Graduate Theses and Dissertations

Trophoblast differentiation and invasion is essential for normal implantation and establishment of the maternal-fetal interface, which allows for proper nutrient exchange and support of the fetus. For this to occur, cytotrophoblasts must undergo an epithelial to mesenchymal transition and differentiate into migratory and invasive extravillous trophoblasts (EVTs) that invade the maternal decidua and myometrium. Trophoblast differentiation, migration and invasion is highly regulated by a complex network of signaling pathways, adhesion molecules and transcription factors and is important for the remodeling of maternal spiral arteries from low flow, high resistance to high flow, low resistance vessels to allow optimal perfusion of …

The Drosophila Neuroblasts: A Model System For Human Ribosomopathies, Sonu Shrestha Baral

LSU Doctoral Dissertations

This dissertation describes the use of Drosophila neuroblasts (NBs) to model human ribosomopathies; the overall goal is to understand why specific stem cell and progenitor cell populations are the primary targets in nucleolar stress as seen in the ribosomopathies. Chapter 1 provides an overview of relevant literature. Chapter 2 describes nucleolar stress in Drosophila neuroblasts as a model for human ribosomopathies. For this, we induce nucleolar stress by using the UAS-GAL4 system to express RNAi that depletes Nopp140 transcripts, and we also employ homozygous, CRISPR-Cas9-generated Nopp140 gene disruptions with a systemic null phenotype (Nopp140-/-). Embryonic lethality was observed …

Analyzing Neuronal Dendritic Trees With Convolutional Neural Networks, Olivier Trottier, Jonathon Howard

Yale Day of Data

In the biological sciences, image analysis software are used to detect, segment or classify a variety of features encountered in living matter. However, the algorithms that accomplish these tasks are often designed for a specific dataset, making them hardly portable to accomplish the same tasks on images of different biological structures. Recently, convolutional neural networks have been used to perform complex image analysis on a multitude of datasets. While applications of these networks abound in the technology industry and computer science, use cases are not as common in the academic sciences. Motivated by the generalizability of neural networks, we aim …