Developmental Biology Commons^™

The Effects Of Aging On Wound Healing And Limb Regeneration In The Axolotl, Hande Sahin

Graduate Masters Theses

The Mexican axolotl is capable of regenerating various parts of its body and maintains this capacity throughout its entire life. Although this ability is sustained through adulthood, multiple regenerative processes appear to be negatively affected by aging. Here, we focus on evaluating the effect of aging on the rate of wound healing and limb regeneration. We have developed new in vivo, and ex vivo assays to characterize wound healing and identify differences between young and aged animals during this process. We have also characterized morphological features of mature skin from both groups of animals and although there are no obvious …

Genetically Explicit Model May Explain Multigenerational Control Of Emergent Turing Patterns In Hybrid Mimulus, Emily Simmons

Biology and Medicine Through Mathematics Conference

No abstract provided.

Translation Control Tunes Drosophila Oogenesis, Elliot T. Martin

Legacy Theses & Dissertations (2009 - 2024)

The decision of a stem cell to either self-renew or differentiate is controlled by specific cellularpathways that can act at the level of transcription, translation, or post-translation. To study the regulation of these pathways in-vivo, I have used the female Drosophila germline as a model system. Each of the steps from germline stem cell (GSC) to egg require changes in cellular pathways. These changes can occur at the level of transcription, post-transciption, translation, or post-translation . Decades of research has elucidated many of the changes to gene that occur during oogenesis, however, many players in this process still remain mysterious. …

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 …

Investigating The Potential Role For The Nervous System In Controlling Regeneration In Nematostella Vectensis, Kristen Malir

Biological Sciences Undergraduate Honors Theses

Nematostella vectensis is a marine sea animal that has become a model for developmental and evolutionary research. Included in the phylum Cnidaria, N. vectensis’ was chosen as the model for this research. Not only can this animal go through asexual and sexual reproduction, but it also has the ability to regenerate. Although much research has been put forth in an effort to understand regeneration better, much is still unknown. The underlying mechanisms of regeneration in Cnidaria are illusive; however, studies within vertebrates have shown the substantial role of the nervous system. The objective of this experiment is to test if …

The Coxsackievirus And Adenovirus Receptor Has A Short Half-Life In Epithelial Cells, Poornima Kotha Lakshmi Narayan, James M. Readler, Mahmoud S. Alghamri, Trisha L. Brockman, Ray Yan, Priyanka Sharma, Vladislav Snitsarev, Katherine J.D.A Excoffon, Abimbola O. Kolawole

Department of Biology Faculty Scholarship and Creative Works

The coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell adhesion, cell signaling, and viral infection. The 8-exon encoded isoform (CAREx8) resides at the apical surface of polarized epithelia, where it is accessible as a receptor for adenovirus entering the airway lumen. Given its pivotal role in viral infection, it is a target for antiviral strategies. To understand the regulation of CAREx8 and determine the feasibility of receptor down regulation, the half-life of total and apical localized CAREx8 was determined and correlated with adenovirus transduction. Total and apical CAREx8 has a relatively short half-life …

Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz

Honors Theses

Phenotypic plasticity is the ability of an organism to integrate information from environmental cues to inform the development of its phenotype and remains understudied in biology. Models of plasticity are needed because evolution in the presence of plasticity is poorly understood. Jadera haematoloma, a hemimetabolous true bug, is an excellent animal model of plasticity, exhibiting a non-linear plastic response to juvenile nutrition that biases adult development into groups with differences in flight capability, wing shape, and fecundity. However, there is a lack of literature consensus regarding the range of developmental outcomes in the species. Some publications report the presence …

Mechanisms Underlying Pre- And Postnatal Development Of The Mouse Vomeronasal Organ, Raghu Ram Katreddi

Legacy Theses & Dissertations (2009 - 2024)

The Vomeronasal organ (VNO) is a specialized olfactory sensory organ located in the ventral region of the nasal cavity in rodents. The vomeronasal epithelium (VNE) of rodents is composed of 2 major types of vomeronasal sensory neurons (VSNs): 1) VSNs distributed in the apical VNE regions that express vomeronasal type-1 receptors (V1Rs) and the G protein subunit Gi2, and 2) VSNs in the basal territories of the VNE that express vomeronasal type-2 receptors (V2Rs) and the G subunit Go. Besides these two neuronal types, VNE also accommodate a third non-neuronal cell type called Sustentacular cells that lie anatomically above apical …

Understanding The Effects Of Embryonic Hyperglycemia On Retinal Development And Maintenance, Kayla Titialii-Torres

Theses and Dissertations--Biology

Hundreds of millions of people are affected by diabetes worldwide. Whether they are diagnosed with prediabetes or Type I or II diabetes, there are a variety of mechanisms in the pathogenesis of diabetes. Diabetes is a disease which consists of recurring states of hyperglycemia that can be difficult to manage due to either lack of insulin production or improper utilization of insulin. While these mechanisms of action differ, complications induced by diabetes occur in both poorly regulated Type I and II. Common complications of diabetes include nerve damage, kidney damage, and eye damage. Eye damage specifically is called diabetic retinopathy …

Understanding The Cellular And Physiological Mechanisms Of Fertilization And Early-Stage Seed Development, Mohammad Foteh Ali

Theses and Dissertations--Plant and Soil Sciences

Flowering plants have evolved a unique double-fertilization process. Two sperm cells fuse with two female gametophytic cells, the egg and central cells within the ovule, giving rise to the embryo and endosperm, respectively. Sperm cells in flowering plants are nonmotile and delivered in close proximity to the egg and central cells by the pollen tube. Flowering plants have established filamentous actin (F-actin) based sperm nuclear migration system for successful fertilization. Prior to fertilization, the female gamete forms a mesh-like structure of F-actin that shows constant inward movement from the plasma membrane periphery to the center of the cell where the …

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 …

Analysis Of Spore Shape Determination In Streptomyces, Ning Sun

Electronic Theses and Dissertations

Streptomycetes are Gram-positive, soil-dwelling bacteria that possess a complex life cycle with the alternation of vegetative mycelium, aerial mycelium, and spores. Streptomyces. coelicolor spore maturation is a complex process that involves spore shape metamorphosis from cylindrical pre-spores into ellipsoid spores, but the details of this process have remained enigmatic. Previously, our lab identified a novel gene ssdA that might play a role in spore shape determination using a transposon-based insertion mutagenesis in S. coelicolor. In this study, I isolated a S. coelicolor ssdA-null mutant that showed increased colony hydrophobicity and misshapen spores in sizes and shapes, confirming the …

Co-Option Of The Yolkless Oocyte Receptor For Crispr/Cas9 May Induce Transient Sterility In Female Drosophila Grimshawi Flies, Bronwyn Miller

LSU New Orleans Theses and Dissertations

Evolutionary developmental biology has historically used generalist model organisms like Drosophila melanogaster. The Hawaiian Drosophilidae radiation, which occurred just 25 million years ago, is an ideal lineage for work in Evo-Devo. Hawaiian flies make up 25% of the world’s Drosophila species and extreme diversity is seen throughout the group. D. grimshawi is a generalist Hawaiian picture-wing fly that has served as a model for the Hawaiian Drosophilidae radiation. However, D. grimshawi’s power and use as a model organism is constrained by our lack of ability to manipulate its genome. In this work, I attempted to edit the genome of …

(Non)Parallel Developmental Mechanisms In Vertebrate Appendage Reduction And Loss, Samantha Swank, Thomas Sanger, Yoel E. Stuart

Biology: Faculty Publications and Other Works

Appendages have been reduced or lost hundreds of times during vertebrate evolution. This phenotypic convergence may be underlain by shared or different molecular mechanisms in distantly related vertebrate clades. To investigate, we reviewed the developmental and evolutionary literature of appendage reduction and loss in more than a dozen vertebrate genera from fish to mammals. We found that appendage reduction and loss was nearly always driven by modified gene expression as opposed to changes in coding sequences. Moreover, expression of the same genes was repeatedly modified across vertebrate taxa. However, the specific mechanisms by which expression was modified were rarely shared. …

Developing Inside A Layer Of Germs—A Potential Role For Multiciliated Surface Cells In Vertebrate Embryos, Ryan R. Kerney

Biology Faculty Publications

This paper reviews current research on the microbial life that surrounds vertebrate embryos. Several clades are believed to develop inside sterile—or near-sterile—embryonic microhabitats, while others thrive within a veritable zoo of microbial life. The occurrence of embryo-associated microbes in some groups, but not others, is an under-appreciated transition (possibly transitions) in vertebrate evolution. A lack of comparable studies makes it currently impossible to correlate embryo-associated microbiomes with other aspects of vertebrate evolution. However, there are embryonic features that should instruct a more targeted survey. This paper concludes with a hypothesis for the role of multiciliated surface cells in amphibian and …

The Effects Of Ppal-1 In Arabidopsis Gamete Development, Amanda J White, Susana Perez-Martinez, Mark P. Running

The Cardinal Edge

Prenylation is a type of post-translational modification in which a 15- or 20-carbon lipid is added to the carboxyl (C) terminus of the protein. Arabidopsis thaliana contains the PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL) gene, which encodes a protein with homology to the α-subunits of the three known prenylation enzymes, PFT, PGGT, and Rab-GGT. We previously identified two mutations in PPAL, one of which is ppal-1, which contains a T-DNA insertion in the fourth intron. We have previously observed that self-fertilizing heterozygous ppal-1 plants produce progeny in which homozygous ppal-1 is underrepresented. This project attempts to ascertain …

Developmental Programming Of Dna Methylation And Gene Expression Patterns Is Associated With Extreme Cardiovascular Tolerance To Anoxia In The Common Snapping Turtle, Ilan Ruhr, Jacob Bierstedt, Turk Rhen, Debojyoti Das, Sunil Kumar Singh, Soleille Miller, Dane A. Crossley Ii, Gina L. J. Galli

Biology Faculty Publications

Background

Environmental fluctuation during embryonic and fetal development can permanently alter an organism’s morphology, physiology, and behaviour. This phenomenon, known as developmental plasticity, is particularly relevant to reptiles that develop in subterranean nests with variable oxygen tensions. Previous work has shown hypoxia permanently alters the cardiovascular system of snapping turtles and may improve cardiac anoxia tolerance later in life. The mechanisms driving this process are unknown but may involve epigenetic regulation of gene expression via DNA methylation. To test this hypothesis, we assessed in situ cardiac performance during 2 h of acute anoxia in juvenile turtles previously exposed to normoxia …

The Slit-Binding Ig1 Domain Is Required For Multiple Axon Guidance Activities Of Drosophila Robo2, Lafreda J. Howard, Marie C. Reichert, Timonthy A. Evans

Biological Sciences Faculty Publications and Presentations

Drosophila Robo2 is a member of the evolutionarily conserved Roundabout (Robo) family of axon guidance receptors. Robo receptors signal midline repulsion in response to Slit ligands, which bind to the N-terminal Ig1 domain in most family members. In the Drosophila embryonic ventral nerve cord, Robo1 and Robo2 signal Slit-dependent midline repulsion, while Robo2 also regulates the medial-lateral position of longitudinal axon pathways and acts non-autonomously to promote midline crossing of commissural axons. While Robo2 signals midline repulsion in response to Slit, it is less clear whether Robo2's other activities are also Slit-dependent. To determine which of Robo2's axon guidance roles …

Analysis Of The Role Of Akirin Interactions With Nuclear Body Proteins During Myogenesis, Laura Yorke

Master of Science in Integrative Biology Theses

Akirin is a highly conserved, small nuclear protein of indeterminate structure ubiquitously expressed in non-fungal eukaryotic species. It was first discovered in the innate immune response, but many other functions have since been found, including embryonic muscle patterning and myogenesis. Animals with either nonfunctional or missing Akirin have aberrations in embryonic muscle patterning, along with other defects. Akirin interacts with transcription factors such as Twist to coordinate development through interfacing between Twist and other complexes, such as the Brahma Chromatin Remodeling Complex (BRM). Therefore, Akirin likely plays a general role in transcription during early development, interfacing with other transcriptional machinery …

Molecular Mechanisms Underlying Cell Fate Choice Within Specific Retinal Lineages, Estie Schick

Dissertations, Theses, and Capstone Projects

During development, retinal progenitor cells (RPCs) divide to form all of the cell types that make up the retina. Multipotent RPCs are competent to generate all retinal cell types, while restricted RPCs form specific lineages of cells. In particular, one genetically-defined RPC type preferentially gives rise to cone photoreceptors and horizontal cells. Many of the mechanisms that are responsible for directing cell fate choice within this lineage are unknown. This thesis largely focuses on examining the development of specific cell types and subtypes from restricted RPCs and on investigating the gene regulatory events that underlie cone photoreceptor and horizontal cell …

Characterizing The Gene Regulatory Network Required To Specify The Excitatory Neurotransmitter Phenotype Of V0v Spinal Interneurons, Amber Kellie Woodard

Theses - ALL

The majority of neurons within the spinal cord are interneurons. Interneurons make important connections with other cells that allow signals to be relayed between the brain and the rest of the body, and aid in functions such as locomotion. One key functional characteristic of interneurons is the neurotransmitter that they use to communicate with other cells. Interneurons that use GABA or glycine neurotransmitters to communicate have an inhibitory phenotype, while interneurons that use glutamate neurotransmitters have an excitatory neurotransmitter phenotype. Without the correct neurotransmitter phenotype, connections within the central nervous system will malfunction. It is therefore important to understand how …

Rna Modification Landscape And Its Contribution To Egg Production, Ian Thomas Rapisarda

Legacy Theses & Dissertations (2009 - 2024)

Germline stem cells differentiate into mature egg or sperm cells that go through the process of fertilization which gives rise to all sexually reproducing organisms. During this process of differentiation, germ cells undergo a switch from mitosis to meiosis that allows for proper development and specification of the future gamete. The mechanisms that facilitate this shift from mitosis to meiosis, however, are not well understood. To gain insight into this process, we used Drosophila oogenesis as our model. To identify what RNA modifications are present during oogenesis we genetically enriched for each stage of development and performed mass spectrometry. We …

The Influence Of Autism Linked Gene Topoisomerase 3b (Top3b) On Neural Development In Zebrafish, Sydney Doolittle

Honors College Theses

Autism Spectrum Disorder is a class of developmental disabilities characterized by a spectrum of social, communication, and behavioral impairments in affected individuals. Studies have shown these defects stem from abnormal brain development during critical periods during early development. The underlying genetic cause of these impairments is not well understood but is believed to be a combination of a complex pairing of genetic and environmental factors. One of the genetic factors that has been recognized to influence the phenotypic symptoms of ASD is the enzyme topoisomerase 3β (top3β.) Topoisomerases are responsible for the prevention of supercoiling during DNA replication. Top3β is …

Cyclin-Dependent Kinase 1 And Aurora Kinase Choreograph Mitotic Storage And Redistribution Of A Growth Factor Receptor, C. D. Cota, M. S. Dreier , '20, W. Colgan, A. Cha, Twan Sia , '21, Bradley Justin Davidson , '91

Biology Faculty Works

Endosomal trafficking of receptors and associated proteins plays a critical role in signal processing. Until recently, it was thought that trafficking was shut down during cell division. Thus, remarkably, the regulation of trafficking during division remains poorly characterized. Here we delineate the role of mitotic kinases in receptor trafficking during asymmetric division. Targeted perturbations reveal that Cyclin-dependent Kinase 1 (CDK1) and Aurora Kinase promote storage of Fibroblast Growth Factor Receptors (FGFRs) by suppressing endosomal degradation and recycling pathways. As cells progress through metaphase, loss of CDK1 activity permits differential degradation and targeted recycling of stored receptors, leading to asymmetric induction. …

The Characterization Of The Function(S) Of Crag In Basement Membrane Polarity, Hemin Pankajkumar Shah

Graduate Research Theses & Dissertations

The abundant epithelial cells play various roles in the development and maintenance of an organism, and their apical-basolateral polarity is a unique characteristic that is imperative to their function and integrity. This polarity is maintained via various environmental cues and tightly regulated intracellular trafficking, where the presence of the basement membrane (BM) provides a basal cue. The BM is a specialized extracellular matrix (ECM) secreted by the epithelial cells, which accumulates on the basal side and serves as their mechanical anchorage. Although the BM is of paramount importance in the apical-basolateral polarity and the loss of BM’s integrity is a …

Transactivation And Mitochondrial Activity Are Affected By High Temperature In C. Elegans Sperm, Jacqueline Mcvay

Scripps Senior Theses

Sexual reproduction has a conserved flaw in that it is temperature sensitive. Exposure to high temperature leads to male infertility, but little is known about the underlying mechanism. Understanding these mechanisms is important for agriculture and reproductive medicine. Using C. elegans, we investigated two potential aspects of male fertility that may be affected by high temperature conditions: activation of sperm by seminal fluid and sperm mitochondrial activity. There are two pathways for sperm activation in C. elegans: the SPE-8 pathway in hermaphrodites and the TRY-5 pathway in male seminal fluid. Hermaphrodite sperm with a mutation in spe-8 can …

Periocular Mesenchyme Heterogeneity During Morphogenesis Of The Vertebrate Ocular Anterior Segment, Kristyn L. Van Der Meulen

Theses and Dissertations--Biology

The vertebrate eye is a complex organ, responsible for the primary sense with which we interact with our environment: vision. Development of the eye is a tightly regulated process, controlled by a vast network of genes. This process begins with eye morphogenesis, when the eye structure is formed through a series of morphogenetic movements and culminates in the creation of the optic cup, lens, and presumptive optic stalk. Next, retinal differentiation creates the critical cell layers of the retina needed to process light waves that enter the eye, including rod and cone photoreceptors, interneurons, and support cells. Failure in either …

Protocadherin-17 Expression And Function In Vertebrate Brain: A Literature Review, Mathea Mcguire

Williams Honors College, Honors Research Projects

For this project, I will be doing a systematic review on protocadherin-17 function in vertebrate brain development and function in the last 10 years. Protocadherins are members of cadherin superfamily. Cadherins are calcium-dependent cell adhesion molecules that are implicated to play crucial roles in the information and maintenance of tissues and organs in vertebrate animals. This review will summarize major findings regarding protocadherin-17 expression and function in major model organisms such as zebrafish and mice, as well as results from human studies. It is hoped that this work will be a valuable source for background knowledge of protocadherin-17 function in …

Molecular Mechanisms Regulating Optic Fissure Fusion During Zebrafish Eye Development, Megan Weaver

Theses and Dissertations--Biology

Vertebrate retinal development requires timely and precise fusion of the optic fissure. Failure of this event leads to congenital vision impairment in the form of coloboma. Recent studies have suggested hyaloid vasculature to be involved in OF fusion. In order to examine this link, we analyzed optic fissure fusion and hyaloid vasculogenesis in the zebrafish pax2a noi mutant line. We first determined that pax2a^-/- embryos fail to accumulate F-actin in the optic fissure prior to basement membrane (BM) degradation. Furthermore, using 3D and live imaging we observed reduced OF hyaloid vascularization in pax2a^-/- embryos. When examining the connection …