Developmental Biology Commons^™

Twist1b Knockout Generation In Zebrafish Using Crispr-Cas9, Grace Hurley

[Archive] Belmont University Research Symposium (BURS)

The Twist gene is found in numerous organisms, including humans, mice and zebrafish (Yeo et al., 2009). It is a vital gene in development and is needed for the organism to survive (Yeo et al., 2009). Specifically, the Twist gene family aids in specialization and differentiation of mesodermal cells, telling somites, segmented blocks of mesoderm, what to become (Germanguz et al., 2007). Over time, the Twist gene has duplicated into paralogs, each having differences in their functions (Germanguz et al., 2007). Twist1b is a protein coding gene that is a paralog to the human Twist1 gene (ZFIN, 2020). In zebrafish, …

Scleraxis Expression Within The Axial Tendon Population In Zebrafish, Jessica Bernaba

[Archive] Belmont University Research Symposium (BURS)

Zebrafish are a well-established model organism for vertebrate development. During embryonic development, a pattern of segmentation of mesoderm yields somites, which give rise to specific cell fates. Somites, bilateral blocks of mesoderm along the neural tube in developing vertebrate embryos, subdivide into sclerotome as the vertebrate matures. Depending on migratory position, sclerotome cells give rise to various components of the axial skeletal system, including bone, cartilage, and tendon. Each fate is determined by gene expressions within the sclerotome and occupy distinct domains of the body plan. By method of in situ hybridization, we studied the expression of the scleraxis ( …

Utilizing Crispr/Cas9 Gene Editing Determine The Role Of Cnr1 During Zebrafish Development, Ellis Chase

[Archive] Belmont University Research Symposium (BURS)

The CRISPR-Cas 9 system is a process used to create mutations, insertions, or deletions within a desired gene. It can be used to create mutant organisms necessary to study the function and impact of a particular gene¹. Cannabinoids are active chemicals found in cannabis, the most common of which being cannabinol (CBD)². Cannabinoid receptors are an integral part of the endocannabinoid system, recognizing cannabinoid signals to promote physiological processes like pain sensation, memory, mood, and appetite³. Studying these cannabinoid receptors can provide insight into how cannabis can affect bodily processes.

Zebrafish are small translucent …

Exploring The Role Of Tgfbr2 During Zebrafish Sclerotome Development, Nooralhuda Feron

[Archive] Belmont University Research Symposium (BURS)

Zebrafish, Danio rerio, are used as a source model organism for human development of the tendons, bones, and ligaments. The sclerotome is an embryonic structure known as the somite. The sclerotome gives rise to axial bones and tendons. During development, different genes are involved and affect how these skeletal tissues develop. Specifically, within this project, the effects of Twist1b and Twist2 were studied to see their effects on tendon formation, as they are expressed within the developing sclerotome tissue. Transforming growth factor beta receptor type-2 (Tgfbr2) has been shown to be involved in tendon formation (Subramanian, Kanzaki, Galloway and …

Gene Expression Pattern Analysis Of Anterior Hox Genes During Zebrafish (Danio Rerio) Embryonic Development Reveals Divergent Expression Patterns From Other Teleosts, Adam Davis

Georgia Journal of Science

The regional identity of organs and organ systems along the anterior-posterior axis during embryonic development is patterned, in part, by Hox genes, which encode transcription factor proteins that activate or repress the expression of downstream target genes. Divergent nested Hox gene expression patterns may have had a role in facilitating morphological divergence of structures, such as the pharyngeal jaw apparatus, among evolutionarily divergent teleost fishes. Recent studies from several evolutionarily divergent teleosts, such as the Japanese Medaka (Oryzias latipes) and the Nile Tilapia (Oreochromis niloticus), have shown the presence of divergent expression patterns of several Hox …

In Situ Analysis Of Line-1 Promoter Activity Using Lacz Transgenic Mice, Partha Sarathi Saha

Electronic Theses and Dissertations

Apart from an evolutionary role, transposable elements have been implicated in animal development and also in pathophysiology. Non-LTR retrotransposons– LINE-1, Alu and SVA - are responsible for over 120 cases of human genetic diseases as heritable insertions, and are emerging as an important etiological factor for cancer and neurological disorders as somatic mutations. It is estimated that among the total number of 500,000 LINE-1s presents in the human genome, 80-100 LINE-1s remain competent for retrotransposition. Retrotransposition is only possible when LINE-1 is expressed. Because LINE-1 transcription is regulated by its 5’UTR promoter, it is essential to understand the spatiotemporal control …

Development And Validation Of Gene Delivery Methods For ​Crassostrea Virginica, Adrienne N. Tracy

Honors Theses

The Eastern oyster (Crassostrea virginica) is an important part of the East Coastal USA economy because aquaculture creates jobs. Sadly, the oysters are under constant threat due to increasing pollution, red tides, and diseases. Bivalves, and oysters in particular, are also becoming potential model organisms in medical research. With the sequencing of the oyster genome, scientists are focusing on deciphering the function of the predicted genes. However, the limited number of molecular and cellular tools available makes functional annotation of the genome challenging. A consistent, replicable gene delivery system needs to be developed to assess gene function and understand the …

The Origin And Evolution Of Flower Characters In Angiosperms With A Case Study On The Genetic Basis Of Zygomorphic Corolla Development In Bee And Hummingbird Pollinated Species Of Schizanthus (Solanaceae), Ghadeer Bukhari

Theses and Dissertations

This Ph.D. dissertation investigates two main projects separated into two chapters, one for each. The first chapter explores the evolution of flowering plants (angiosperms), a macro-scale study. The second project is on a micro-scale that focus on exploring the genes that regulate the similarities and the differences of flower morphology reflecting their different pollination syndromes in two species of Schizanthus (Solanaceae), i.e., S. pinnatus, a bee-pollinated flower, and S. grahamii, a hummingbird- pollinated flower.

In the first chapter, I used floral diagrams to study the origin and the evolution of floral traits in angiosperms, a new set of morphological data …

Analysis Of Adult Neural Retina Extracellular Vesicle Release, Rna Transport And Proteomic Cargo, Jason Mighty, Jing Zhou, Alberto Benito-Martin, Sami Sauma, Samer Hanna, Onyekwere Onwumere, Cui Shi, Martin Muntzel, Moira Sauane, Michael Young, Henrik Molina, Dianne Cox, Stephen Redenti

Publications and Research

PURPOSE. Extracellular vesicles (EVs) contain RNA and protein cargo reflective of the genotype and phenotype of the releasing cell of origin. Adult neural retina EV release, RNA transfer, and proteomic cargo are the focus of this study.

METHODS. Adult wild-type mouse retinae were cultured and released EV diameters and concentrations quantified using Nanosight. Immunogold transmission electron microscopy (TEM) was used to image EV ultrastructure and marker protein localization. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze retinal cell transcripts present in EVs. Super-resolution microscopy was used to image fluorescent (green) RNA and (red) lipid membrane labeled EVs, released …

The Roles Of Polar Cell Extensions In Drosophila Micropyle Formation, Bradford Hull

Theses and Dissertations--Biology

The Drosophila micropyle is a conserved formation utilized to allow sperm passage past the robust eggshell structure for fertilization. Micropyle formation follows a unique acellular tubulogenesis method where it is secreted and shaped by specialized follicle cells including the border cells and polar cells. In late oogenesis, the polar cells form extensions that are necessary to create the micropyle pore through which sperm enters. Previous work established that polar cell extension presence is required for micropyle pore formation. We investigated temporal requirements of extensions throughout chorion deposition and found extensions are required during the beginning and middle of choriogenesis, but …

Dispelling The Mirage Of C4-Driven Drought Tolerance In Poaceae: A Phylogenomic Study, Matthew P. Nissenbaum

Graduate Research Theses & Dissertations

Climate change has been considered a key driver for adaptations in water usage efficiency (WUE) in plants. Perceptions persist that C4 photosynthesis is indicative of some level of WUE. Here, we examined the interaction and evolution of WUE within the grass family, Poaceae, as it pertains to photosynthetic pathway. Unique to this study is the magnitude of taxa sampled, presence of intrageneric sampling, and use of complete plastid genomes (plastomes) for phylogenomic analyses.

310 species were sampled, including 26 with newly sequenced plastomes, which were assembled de novo from next-generation sequencing data. Additional plastomes were downloaded from the National Center …

The Effects Of Internal Physiology On Polyphenic Horn Development In The Dung Beetle Onthophagus Taurus, Naomi Garrett Williamson

Graduate Theses, Dissertations, and Problem Reports (ETD)

An organism’s phenotype can be affected in development by alterations to gene expression based on environmental inputs. Nutrition is one such environmental input and the central regulator of development of large horn or small horn phenotypes in the dung beetle species, Onthophagus taurus. However, little is known about the nature of chemical compounds that are critical to this plastic horn development. To better understand these compounds, we are utilizing an untargeted metabolomic approach as well as a targeted gene approach. Through the metabolomic approach, it was uncovered that environmental conditions tend to have a greater impact on metabolomic composition …

Developmental Mechanisms For The Diversification Of Polyphenic Morphs In The Head Horn Of Onthophagine Beetles (Coleoptera: Scarabaeidae Onthophagus Taurus): Plasticity Through Nutrition, Logan Paul Zeigler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Developmental plasticity is the phenotypic variation between organisms that is caused by environmental interactions affecting the developmental systems of organisms. The research focused primarily on nutrition-responsive developmental plasticity. In this research we used the nutritionally determined head horn development of Onthophagus taurus to better understand the developmental mechanisms and genetic underpinnings of nutrition-responsive trait development. We focused specifically on altering the availability of specific nutrition-related primary metabolites, cholesterol and palmitic acid, identified in the activity of The Hedgehog pathway, a critical pathway in head horn development. By altering diet composition using cholesterol, reducing transcript expression of an acyltransferase gene, rasp …

A Transcriptomic Exploration Of Hawaiian Drosophilid Development And Evolution, Madeline M. Chenevert

LSU New Orleans Theses and Dissertations

One in four known species of fruit flies inhabit the Hawaiian Islands. From a small number of colonizing flies, a wide range of species evolved, some of which managed to reverse-colonize other continental environments. In order to explore the developmental pathways, which separate the Hawaiian Drosophila proper and the Scaptomyza group that contains reverse-colonized species, the transcriptomes of two better-known species in each group, Scaptomyza anomala and Drosophila grimshawi, were analyzed to find changes in gene expression between the two groups. This study describes a novel transcriptome for S. anomala studies as well as unusual changes in gene expression …

Genetic Analysis Of A Novel Ftsk Homolog, Hfka, In Streptomyces Coelicolor Development-Associated Chromosome Segregation, Sumedha Sethi

Electronic Theses and Dissertations

A quintessential phenomenon occurring during prokaryotic development is accurate segregation of the replicated genomes into the daughter cells. Key energy-dependent processes like chromosome condensation and subcellular partitioning of the genomes are driven by conserved proteins like SMC, ParB, FtsK. During its complex developmental cycle, Streptomyces coelicolor segregates its genomes into chains of unicellular spores when its multigenomic syncytial aerial hyphae undergo division.

A novel ftsK-like gene, hfkA (Homolog of FtsK protein A), was examined for function and localization during development-associated chromosome segregation. Individual deletions did not affect segregation, but a ΔhfkA ΔftsK mutant exhibited 8% anucleate …

Genetics With Nettie And Friends: An Exploration Of Genetics In Children's Literature, Erin Soule, Madeleine Gray Burland

Honors Projects

Genetics with Nettie and Friends is an exploration of chromosomal disorders and its place within children's literature. The book provides a comprehensive examination the genetic composition of Downs syndrome, Williams Syndrome, and Duchenne muscular dystrophy at a level to increase understanding in children. This paper provides an insight to the development and construction of the children's book that is available for purchase on Barnes and Noble as well as why representation of genetic disorders in children's literature is needed.

Functional Importance Of Lipin Phosphorylation, Stephanie Elizabeth Hood

Graduate Theses and Dissertations

Highly conserved throughout evolution, lipins are dual functioning proteins found from yeast to humans. Functioning in the cytoplasm as phosphatidate phosphatase enzymes (PAP), lipins produce diacylglycerol that serves as a precursor for neutral fats and membrane phospholipids. Alternatively, nuclear lipins are responsible for the regulation of metabolic genes. Interestingly, both the mammalian lipin 1 paralog and the single Drosophila Lipin ortholog are highly phosphorylated proteins. Target of rapamycin (TOR) has previously been identified as one of the kinases that controls the subcellular localization of both lipin 1 and Drosophila Lipin. However, other serine and threonine kinases are predicted to be …

Dynamics Of Trophoblast Differentiation In Peri-Implantation–Stage Human Embryos, Rachel C. West, Hao Ming, Deirdre M. Logsdon, Jiangwen Sun, Sandeep K. Rajput, Rebecca A. Kile, William B. Schoolcraft, R. Michael Roberts, Rebecca L. Krisher, Zongliang Jiang, Ye Yuan

Computer Science Faculty Publications

Single-cell RNA sequencing of cells from cultured human blastocysts has enabled us to define the transcriptomic landscape of placental trophoblast (TB) that surrounds the epiblast and associated embryonic tissues during the enigmatic day 8 (D8) to D12 peri-implantation period before the villous placenta forms. We analyzed the transcriptomes of 3 early placental cell types, cytoTB (CTB), syncytioTB (STB), and migratoryTB (MTB), picked manually from cultured embryos dissociated with trypsin and were able to follow sublineages that emerged from proliferating CTB at the periphery of the conceptus. A unique form of CTB with some features of STB was detectable at D8, …

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 …

Effects Of Meiotic Drive On Developing Eye-Stalks In Stalk-Eyed Flies, Christopher Lepore, Olivia Smith, Heather Wood, Josephine Reinhardt Phd

McNair Scholars Program

Teleopsis dalmanni, commonly known as Stalk-Eyed flies, are known for their sexually dimorphic eye-stalks which females use to pick mates. Within the Gombak-12 population, some individuals contain meiotic drive which is known to influence eye-stalk length and sex ratios. Our goal was to identify genes in developing eye tissue that play a role in causing meiotic drive. To identify these candidate genes, we determined the sex and meiotic drive status of individuals by dissecting 3rd instar larvae for their carcasses. After finding that Qiagen Puregene and Qiagen DNEasy columns DNA extraction techniques worked best—determined by using gel electrophoresis—we prepared …

Notch Inhibitors And The Bet Inhibitor Jq-1 Decrease The Growth Of Primary Tumor Cells Derived From A Novel Mouse Model Of C11orf95-Rela Induced Brain Tumor, Ericka Randazzo, Jesse Dunnack, Justin Fang, Joseph Loturco Phd

University Scholar Projects

Brain tumors are the most common childhood solid malignancy, and because of remarkable advances in treating many cancers outside of the brain, they have become the leading cause of cancer mortality in children. Ependymomas are a class of brain tumors which can be further subdivided into three groups based upon their location and genetic features. Of the three classes, supratentorial ependymomas are the only subgroup known to be marked by an oncogenic driver gene, which consists of a fusion mutation between the C11orf95 and RELA genes. C11orf95-RELA positive tumors are the most aggressive and lethal of …

A Novel Kinesin Adapter Directly Mediates Dendritic Mrna Localization During Synapse Development, Hao Wu

Dissertations, Theses, and Capstone Projects

Cytoskeleton based active transport with motor proteins is essential for mRNA localization and local protein translation in animal cells, yet how mRNA granules interact with motor proteins remains poorly understood. Using an unbiased screen for interaction between mRNA binding proteins (RBP) and motor proteins, we identified protein interacting with APP tail 1 (PAT1) as a potential direct adapter between the β-actin mRNA Zipcode-binding protein 1 (ZBP1) and Kinesin-1 motor complex.

Mouse PAT1 is similar to the Kinesin Light Chain (KLC) in amino acid sequence and binds directly to KLC. High-resolution images from structured illumination microscopy (SIM) indicates that synaptic stimulation …

Platiscity Of C. Elegans Germline Stem Cells Under Nutritional And Metabolic Stress, Kenneth Trimmer

Dissertations and Theses (Open Access)

Stem cells are integral for tissue maintenance and fertility. Therefore, understanding how stem cells are regulated under stress is imperative. When confronted with acute starvation, stem cells must conserve energy and metabolites to cope with the lack of an external source. Caenorhabditis elegans germline stem cells (GSCs) are an excellent model for studying stem cell properties and regulation as they can divide throughout the life of the organism. While GSCs are an adult stem cell population, their cell cycle structure more closely mimics mouse and human embryonic stem cells with short G1 and long S phases. In this thesis, I …

Insects And The Evolution Of Developmental Pathways: Functional Analysis Of Genetic Sex Determination Mechanisms In Oncopeltus Fasciatus, Josefine Just

Honors Theses

Natural selection alters genetic pathways over evolutionary time. However, different pathways have been shown to maintain mutations at varying rates, leading to different levels of conservation across developmental pathways. Sex determination pathways, in particular, show vast diversity across animals despite the fundamental conservation of biological sex itself. Here, I investigated the sex determination pathway of the hemimetabolous insect, Oncopeltus fasciatus. The large milkweed bug, O. fasciatus, is part of the order Hemiptera, which provides a relevant outgroup study to other insects in which sex determination has been studied to date. I studied three sex determination genes, intersex, fruitless …

Characterizing Chromosomal Aberrations In Cells Deficient For Both Atm And Msh2, Yeliz Inalman

Dissertations and Theses

Ataxia telangiectasia mutated (ATM) and mutS homologue 2 (MSH2) are important DNA repair proteins that participate in DNA repair pathways to maintain genomic integrity. Mice deficient for ATM and MSH2 mice are viable. However, ATM^-/- mice show growth retardation, neurological defects, and spontaneous lymphomagenesis. MSH2^-/- mice suffer from aggressive lymphoid tumors between two to five months of age and have increased microsatellite instability, which predisposes MSH2^-/- mice to carcinomas. However, mice deficient in both ATM and MSH2 are unable to survive beyond postnatal day 21 (P21). The observed lethality in ATM^-/-MSH2^-/- mice may result …

Effect Of Larval Starvation On Lipid Content Of Drosophila Melanogaster Over 15 Days, Fabian Leija, Allen Gibbs

LSAMP Poster Presentations

Starvation-resistant Drosophila melanogaster, common fruit flies, deriving from 121 generations of starvation selection, have resulted in genetically, behaviorally, and physiologically different individuals compared to non-resistant counterparts. Starvation-resistant Drosophila are more obese, containing twice as much lipids as control flies.This is a result of starvation-resistant fly larva feeding for 5 days and then entering the pupa stage while non-resistant flies only feed for 4 days.

In this experiment, we hope to answer the question of whether the starvation-resistant flies are genetically predisposed to be substantially more obese than wild populations or if it is a result of this alternate behavior …

Integration Of Bmp And Insulin/Igf-1 Signaling Regulates Multiple Homeostatic Functions In Caenorhabditis Elegans, James F. Clark

Dissertations, Theses, and Capstone Projects

The maintenance of homeostatic functions is key to the survival and well-being of an organism. Regulation of homeostasis relies on varied inputs, both intrinsic and extrinsic, to potentiate a web of interconnected signaling relays. Insulin/IGF-1 signaling (IIS) is a well-known regulator of glucose and lipid metabolism, as well as having far reaching effects in other homeostatic mechanisms. On the other hand, bone morphogenetic protein (BMP), a member of the transforming growth factor beta signaling superfamily, is known for its role in differentiation and development, with only recent studies highlighting potential roles in metabolic homeostasis. Here we elucidate new functions for …

Characterizing Epigenetic Regulation In The Developing Chicken Retina, Bejan Abbas Rasoul

Masters Theses, 2010-2019

The retina, the sensory neuronal tissue within the eye, is composed of three layers of neuronal cells connected by two synaptic layers lining the inside of the anterior portion of the eye. Multipotent retinal precursor cells are genetically homogeneous and differentiate into mature retinal neurons due to differential gene expression. Differences in gene expression have been correlated with epigenetic modifications such as DNA methylation. DNA methylation of upstream regulatory elements is associated with transcriptional silencing of gene expression. Years of research in retinal development has identified the numerous genes expressed during the main steps of retinal development, however, it is …

Phosphorylation Impairs Dicer1 Function To Accelerate Aging And Tumorigenesis In Vivo, Neeraj Aryal

Dissertations and Theses (Open Access)

Altered DICER1 protein levels are associated with developmental disorders, infertility, macular degenerative blindness, aging, and cancer in humans. Recently, post-translational regulation of Dicer1 via phosphorylation has been described in C. elegans. Oscillation of Dicer1 phosphorylation to regulate its activity is essential for germ cell development and embryogenesis in worms. These observations led us to posit that Dicer1 protein levels and activity are under tight regulation for normal mammalian homeostasis. To test whether phosphorylation of Dicer1 regulates its activity in mammals, I generated phospho-mimetic knock-in mouse models by replacing Serines 1712 and 1836 with Aspartic acids individually or together (dual …

Genetic Basis Of Larval Crystal Cell Quantity Variation In The Drosophila Genetic Reference Panel (Dgrp), Brian Tang

Student Theses and Dissertations

Crystal cells are one of three requisite hemocytes that take part in fighting infection and wound healing in Drosophila melanogaster (common fruit flies). The developmental genetics of crystal cell formation is only beginning to be discovered. To address this question, we performed a Genome-Wide Association Study (GWAS) on larval crystal cell number from 78 isolines of the Drosophila Genetic Reference Panel (DGRP) collection. The DGRP consists of naturally caught fruit flies that are inbred to near homozygosity with completely sequenced genomes. By placing the wandering third instar larvae under heatshock, a process that induces the melanization of crystal cells, …