Cell and Developmental Biology Commons^™

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 …

Analysis Of Differential Gene Expression Patterns During Spiral Intestine Development In Leucoraja Erinacea, Kelsey Cox

Honors Theses

The vertebrate gut is a specialized structure responsible for the intake and digestion of food, absorption of nutrients, and expulsion of waste products. The organs of the digestive tract have been conserved over time, but modifications to the size and shape of individual structures exist within the different vertebrate lineages. The skate’s spiral intestine has evolved to maximize nutrient absorption within a compact structure to create space in the body cavity for the organs needed for buoyancy. Studying the unique intestinal morphology of Leucoraja erinacea, or the little skate, provides an opportunity to understand the role of differential gene expression …

Elucidating The Functional Location Of Platelet-Derived Growth Factor Receptor Alpha, Creation Of A Review Chapter On The Use Of Zebrafish In Studying Congenital Heart Defects, And Using 3d Printing To Create Laboratory Tools, Jaret Lieberth

Honors Theses

Congenital heart defects (CHDs) are currently the most prevalent form of birth defect in the United States. Their combined frequency and severity make necessary a deeper understanding of the molecular underpinnings guiding heart formation. The first major step in cardiac morphogenesis, cardiac fusion, involves the medial movement of bilateral populations of myocardial precursor cells to the embryonic midline, where they merge to form the primitive heart tube. Although crucial to subsequent organogenesis, the precise mechanisms governing cardiac fusion remain unknown. Previous studies have found that a mutation in platelet-derived growth factor receptor alpha (pdgfra), called refuse-to-fuse (ref), results …

Evaluation Of The Bax-Vdac Interaction And Their Influence On Apoptosis In Drosophila Melanogaster, Frances Marie Gatlin

Honors Theses

Apoptosis, also known as programmed cell death, is a cellular process used for development or for when cells undergo injury or stress. The Bcl2 family of proteins includes both pro-apoptotic and anti-apoptotic proteins that control the intrinsic pathway of apoptosis. Understanding the mechanisms and influence these proteins have on apoptosis is an important area of research focused on in Dr. Jones’s lab. Evidence shows a homology amongst the Bcl2 family of proteins at the BH3 domain. Dr. Jekabsons' lab has found a potential homology amongst VDAC 1-3 and the Bcl2 family at the BH3 domain.

Specifically, our lab is using …

Exploring The Role Of Ccdc141 In Zebrafish Heart Development, Luci Strong

Honors Theses

Zebrafish are a good model organism in which to identify genes important for heart development because most human genes have a zebrafish ortholog and genes in zebrafish are relatively simple to modify. ccdc141 is a gene with unknown function, which we originally found to be highly expressed in cardiac cells in mouse embryos. In this project, we are seeking to determine the function of ccdc141 using zebrafish. To perform this experiment, we are targeting ccdc141 for mutation using CRISPR/Cas9. In this project we have analyzed ccdc141 to determine regions of conservation, designed CRISPR guides to target those regions (exon 2 …

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 …

Mouse Embryonic Stem Cells Are Sensitive To The Cytotoxicity Of Nitric Oxide: Biological Implications For Early Embryogenesis, Mckenzie C. Hargis

Honors Theses

The early embryo, before implantation, is at a very vulnerable stage in development where it faces various inflammatory cytokines throughout the implantation process. In this stage, the cells in the blastocyst, the preimplantation stage embryo, must proliferate rapidly for tissue formation. However, it is known that inflammatory cytokines can inhibit cell proliferation. Previous studies have shown that embryonic stem cells (mESCs), the major cell component in the blastocyst, are unresponsive to treatments of tumor necrosis factor ⍺ (TNF⍺) and interferon 𝛾 (IFN𝛾), two inflammatory cytokines involved in the implantation process. Treatment of mESC-differentiated fibroblasts (mESC-FBs) with TNF⍺ and IFN𝛾 in …

Investigating Roles For Rna Turnover Processes In Cell Signaling Through Drosophila Melanogaster Genetic Mosaics, Sudiksha Rathan Kumar

Honors Theses

The process of cell signaling is vital in organisms for proper development as it determines the fate and function of cells. This process is highly regulated by myriad interactions between signaling pathway components and gene expression mechanisms. RNA turnover is a type of RNA processing that degrades RNA. It plays an essential role in homeostasis and environmental changes; however, its influence on signaling pathways is currently unknown. In the present study, the effect of RNA turnover processes on cell signaling was analyzed using the genetic mosaics in Drosophila melanogaster. Fly mosaics were created by breeding RNAi lines targeting cellular …

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 …

Fetal Programming Of Intrauterine Growth Restricted Skeletal Muscle Stem Cell Function, Micah Most

Honors Theses

Intrauterine growth restriction (IUGR) reduces skeletal muscle mass in fetuses and offspring. The objective of this study was to determine if myoblasts (skeletal muscle stem cells) from maternal inflammation induced intrauterine growth-restricted (MI-IUGR) fetuses are less responsive to proliferation-stimulating factors in culture. Ovine MI-IUGR fetal myoblasts were isolated at 125 days of gestational age (dGA, term = 150 dGA), grown for 72 hours in complete growth media spiked with insulin, tumor necrosis factor α (TNFα), or unspiked (basal), and analyzed for ex vivo proliferative capacity via a 2 hour EdU pulse. A second set of myoblasts were differentiated in differentiation …

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 …

Examining The Effects Of Fadrozole, An Aromatase Inhibitor, On Testosterone And Estrogen Production Of Domestic Chicken Embryos (Gallus Gallus), Abby E. Joseph

Honors Theses

The hypothalamic-pituitary-gonadal (HPG) axis is responsible for the production of the hormones testosterone and estradiol, and testosterone is thought to contribute to regulation of the axis through a negative feedback mechanism. Regulation by negative feedback involves the product of a pathway turning off that pathway when enough product is made. However, because the enzyme P450 aromatase converts testosterone to estradiol, estradiol may also contribute to regulation of the HPG axis and other phenomena that have been attributed to testosterone, like the inhibition of immune function. Previous studies have injected birds with an aromatase inhibitor (presumably reducing estradiol production) and shown …

Vein Patterning During Juvenile Wing Development In Oncopeltus Fasciatus And Jadera Haematoloma, William R. Simmons

Honors Theses

Wings are a defining characteristic of all pterygote insects and are agreed to originate from a single common winged ancestor. However, essentially nothing is known about the molecular mechanisms that regulate wing development and patterning outside of Endopterygota, and the vast majority of this knowledge comes solely from Drosophila melanogaster. There is reason to suspect that the drastic developmental differences that exist between Endopterygota and Exopterygota have resulted in changes in the mechanisms, timings, or even genes that govern wing development. This study examined the roles of several genes known to be involved in D. melanogaster wing development and patterning …

The Uas-Gal4 System In D. Melanogaster: An Insight Into The Influence Of Micrornas On The Developmental Pathways Of The Wing, Emily R. Wilson

Honors Theses

By examining genetic pathways in D. melanogaster, a better understanding of the homologous regulatory mechanisms in humans can be utilized to further enhance knowledge of the roles of microRNA within development. This study utilizes the UAS-Gal4 system in order to produce a mutant phenotype capable of being visually studied and analyzed, focusing on the developmental pathway of the wing in D. melanogaster. Dissections of the wandering third instar larvae yielded wing disc tissue expressing the downregulation of loquacious and CG17386.

Investigating The Co-Regulatory Role Of Midline And Extramacrochaetae In Regulating Eye Development And Vision In Drosophila Melanogaster, Lillian M. Forstall

Honors Theses

The Honors thesis research focused on the roles of extramacrochaetae and midline in regulating eye development and the vision of Drosophila melanogaster. It is known from previous studies that extramacrochaetae (emc) and midline (mid) independently regulate the formation of ommatidial units in the Drosophila compound eye. However, the thesis focuses on the interaction of these two genes and their co-dependent roles in regulating eye development. This study also attempts to explain the recovered formation of ommatidial units and interommatidial bristles when the expression of both of these genes is reduced and whether flies doubly mutant …

The Differential Roles Of D-Pax2 Variants In Regulating Drosophila Eye And Bristle Development, Colin J. O’Shea

Honors Theses

The ability to appropriately interact with the environment is crucial to an organism’s survival. The establishment of functional sensory systems, such as the bristles and eyes in Drosophila, is a critical event during the development of the organism. The transcription factor D Pax2 is involved in the differentiation of the shaft and glial cells in the developing bristle (Kavaler et al., Dev, 126:2261-2272, 1999) and of the cone and primary pigment cells in the developing eye (Fu and Noll, Genes Dev, 11:389-405, 1997). How D-Pax2 contributes to distinct differentiative pathways in different cell types is not known. Recent work by …

The Effects Of Moist-Heat Treatments And Stratification On Germination Of Prairie Plant Seeds, John E. Stuurwold

Honors Theses

Germination of Silphium terebinthenaceum was enhanced by a post-stratification most-heat treatment at 80°C. Tested seeds of four other perennial herbs common to midwestern prairies (Andropogon scoparius, Sorghastrum nutans, Eryngium yuccifolium, and Solidago rigida) showed little adverse or beneficial effects of the heat treatment. Heat treatments alone had little effect on the seeds; the length of stratification periods necessary to effect maximal germination varied. The significance of these findings is examined in the light of related literature on grassland fire ecology.