Genetics Commons^™

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 …

Determining The Genetic Control Of Neural Tube Malformation Through Genetic Interactions With Idgf3, Elli N. Fox

Honors Projects

Genetic mutations disrupting human neural tube formation can lead to birth defects such as spina bifida and anencephaly. Defects can result in lack of neural tube closure in either the caudal (spina bifida) or cranial (anencephaly) regions. Little is known about the genes that cause these malformations. Researchers have been using the model organism Drosophila melanogaster in an attempt to determine genes responsible for neural tube malformations. Recently, an ortholog of human chitin-like protein, imaginal disc growth factor 3 (Idgf3), has been identified as important in the proper formation of Drosophila egg dorsal appendages. However, the molecular mechanism responsible for …

Multi-Generational Effects Of ∆9-Tetrahydrocannabinol Exposure On Gene Expression In Liver Tissue, Kayla Lovitt

Honors Theses

Cannabis is the most commonly used, cultivated, and trafficked illicit drug worldwide. Increased availability and acceptance of cannabis and cannabinoid-containing products provide the necessity for understanding how these substances influence aging. In this study, zebrafish (Danio rerio) were exposed to concentrations of Δ⁹-tetrahydrocannabinol (THC) (0.08, 0.4, 2 µM) during embryonic-larval development, the effects on aging were measured 30 months later and in the offspring of the exposed fish (F1 generation. We observed results indicating a biphasic and hormetic effect. Treatment with the lowest concentration of THC significantly increased egg production, while higher concentrations resulted in impaired …

Using A Novel Cell- Penetrating Peptide Technology To Induce Pluripotency, Laura-Maria Oja

Master of Science in Chemical Sciences Theses

Somatic stem cells have been used as a regenerative medicine tool to treat diseases like leukemia for decades, but they are limited in their ability to self-renew and differentiate. A better alternative, induced pluripotent stem cells (iPSCs), has the ability to generate cells from all three germ layers and avoid tissue rejection as well as bypass the ethical concerns related to embryonic stem cells. In 2006, Takahashi and Yamanaka discovered that only four genes were required to induce pluripotency: Oct4, Sox2, Klf4, and c-Myc (OSKM). Since then, pluripotency has been induced with OSKM most effectively by transfection or transduction. However, …

Utilizing Crispr/Cas9 Gene Editing Determine The Role Of Cnr1 During Zebrafish Development, Camme Sells

[Archive] Belmont University Research Symposium (BURS)

In a world where cannabinoids are being used more frequently as for medicinal purposes, the importance for research on cannabinoid biology is steadily increasing. The goal of this study was to gain a greater understanding of the effect cannabinoids have on developing zebrafish embryos. Work in this area of developmental biology could give way to an understanding of the safety of a human fetus during pregnancy with a mother who uses cannabis medicinal therapy. The CRISPR/Cas 9 system was utilized in this study to genetically edit the zebrafish embryo genome to remove the function of the Cannabinoid Receptor 1 ( …

Using Crispr/Cas9 Gene Editing To Remove Twist2 To Determine Its Role During Somite Development In Zebrafish, Caleb Holdener

[Archive] Belmont University Research Symposium (BURS)

Embryonic Mesoderm is a precursor to various types of tissues, such as the somatic mesoderm. Somites are a segmented tissue that gives rise to the sclerotome in vertebrates. This sclerotome further develops into the axial skeleton (Stickney, Barresi, and Devoto 2000). Somites are easily observable under low power microscopy during fish development. In fish, great strides have been made in studying the developmental fate of somites (Stoiber, Haslett, and Sänger 1999; Stickney, Barresi, and Devoto 2000). Zebrafish have been studied in many labs due to their similarities with higher vertebrates. These advantages include their inexpensive cost of care, external fertilization, …

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, …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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, …

Why Doesn’T A Mother Reject A Genetically Different Fetus?, Devora Krumholtz

The Science Journal of the Lander College of Arts and Sciences

Many basic multicellular organisms possess some form of immune response to protect themselves against the invasion of foreign objects. It was not until British scientist, Peter Medawar proposed a fundamental question that changed the way researchers studied the maternofetal relationship. A fetus, being genetically different from its mother should be rejected by the maternal immune system, however, it is not. Researchers have since discovered and developed several mechanisms that aim to explain how the maternal immune system prevents fetal rejection. The formation of a mechanical barrier, general and local suppression of the maternal immune system, and a shift in cytokine …

Jak/Stat Signaling Regulates Gametogenesis And Age-Related Reproductive Maintenance, Michelle Suzanne Giedt

Theses and Dissertations--Biology

Cell signaling is central to integration of internal and external cues that regulate development and homeostasis. Most development is thought of as pre-adult, but limited developmental processes occur in adults. Gametogenesis incorporates elements of both these facets, with a distinct developmental plan for gamete synthesis which is regulated by integration of homeostatic inputs such as nutrient status, and environmental cues. Signaling pathways integrate and transduce information from these cues to evoke a response. A decline in homeostasis and subsequent cues occurs over time, in the case of reproductive tissues leading to a progressive loss of fertility. The Janus Kinase and …

An Undergraduate Laboratory Manual For Analyzing A Crispr Mutant With A Predicted Role In Regeneration, Susan Walsh, Ashley Becker, Paxton S. Sickler, Damian G. Clarke, Erin Jimenez

Faculty Publications

Exposing students to undergraduate research has reportedly improved students’ development of knowledge and skills in the laboratory, self-efficacy, satisfaction with their research, retention, and perseverance when faced with obstacles. Furthermore, utilizing authentic course-based undergraduate research experiences (CUREs) includes all students enrolled in the class, giving those who may not otherwise have access to an independent undergraduate research project an opportunity to engage in the scientific process in context of an original, unanswered question. In the fall of 2016, second semester introductory biology students conducted a semester-long research project on the transcription factor Lin28a to determine the effect of Lin28a on …

The Dlk1-Meg3 Locus In Malignant Cells Of Proposed Primordial Germ Cell Origins., Zachariah Payne Sellers

Electronic Theses and Dissertations

Primordial germ cells (PGCs) are hypothesized to deposit hematopoietic stem cells (HSCs) along their migration route through the embryo during the early stages of embryogenesis. PGCs also undergo global chromatin remodeling, including the erasure and reestablishment of genomic imprints, during this migration. While PGCs do not spontaneously form teratomas, their malignant development into germ cell tumors (GCTs) in vivo is often accompanied by the retention of hypomethylation at the IGF2-H19 imprinting control differentially methylated region (DMR). Previous studies in bimaternal embryos determined that proper genomic imprinting at two paternally imprinted loci was necessary for their growth and development: Igf2-H19 and …

Epigenetic Modifications Of Human Placenta Associated With Preterm Birth, Drissa Toure

Theses & Dissertations

Preterm birth is a complex multifactorial process. Despite the well-known role of the placenta in supporting the fetal development and maternal-fetal tolerance, the placental epigenetic modifications and preterm birth (PTB) remains poorly understood and under investigated. Various maternal and environment factors can influence epigenetic programming during fetal development to affect the functioning and structures of organs, including the placenta, which can lead to adverse pregnancy outcomes, including PTB. The understanding of the placental epigenetic alterations and maternal determinants associated with PTB are apparently indispensable for the development of actual diagnosis and methods of prevention and treatment of premature labor. The …

Characterization Of Myod And Myf5 Double-Knockout Muscle Stem Cells During Muscle Development, Andreea Dinicu

University Scholar Projects

MyoD and Myf5 are transcription factors that regulate myogenesis by promoting satellite cell transcription. The two genes are known to display functional redundancy. Both genes are considered myogenic determination genes and are expressed in satellite cells. The fate of myogenic precursors in the absence of both MyoD and Myf5 remains largely unknown. We aimed to begin attaining this knowledge as part of this project. We utilized a CreLoxP system to control the expression of MyoD in mice lacking Myf5. MyoD was knocked out at embryonic day (E) 11.5 during myogenesis. Limbs were collected from experimental mice following tamoxifen injection. …

Post-Transcriptional Regulation Of The Drosophila Anterior Determinant, Bicoid, John Mclaughlin

Dissertations, Theses, and Capstone Projects

In a wide variety of biological contexts, messenger RNA (mRNA) is known to have a complex and dynamic life cycle. In particular, the localization and translational control of mRNA are essential for proper development in eukaryotes. The fly Drosophila melanogaster is an excellent model for studying these processes. During D. melanogaster oogenesis, several mRNAs are trafficked and localized within the developing egg chamber, and regulated at the translational level to enable embryo patterning. One such mRNA, bicoid, is localized at the anterior of the oocyte and translated in the early embryo, where its encoded protein directs formation of the fly's …