Developmental Biology Commons^™

Epigenetic Regulation Of Insect Development, Yaoyu Jiao

Theses and Dissertations--Entomology

Insects undergo a series of distinct life stages such as egg, larva and pupa to develop into mature adults capable of reproduction throughout their life cycle. In the larval stage, insects experience the fastest growth with voracious feeding and multiple cuticle shedding resulting in hundreds-of-fold increasing of size. During metamorphosis, insects stop increasing body size but go through dramatic tissue transformation, developing wings and other adult features. The characteristic mode of insect development, especially the metamorphosis, makes insects the most successful group of animals on the earth. However, the epigenetic mechanisms behind insect development remain elusive. Studying the epigenetic regulation …

Parental Instincts: The Neurological And Biological Factors Associated With Parenthood, Jared Reeder

Undergraduate Honors Theses

The following project involves a systematic review of the scientific literature on neural and biological changes of mothers and fathers in parenthood. Until very recently, little scientific research was devoted to studying how bearing children affects a man or woman’s long-term biology. Over the last twenty years, studies of neuroplastic changes in new mothers show specific neural mechanisms responsible for altering the behaviors of mothers during and after pregnancy. These changes in neuroplasticity alter behavior in such a way that led to mothers requiring less sleep and being more prone to hearing the cries of their children. In addition to …

The Effect Of Larval Competition On Adult Life History Traits And The Immune Response Of Adult Cat Fleas (Ctenocephalides Felis), Piper N. Zellner, Lisa D. Brown

Honors College Theses

In holometabolous insects, conditions during the larval stage can affect the adult stage. For instance, in mosquitoes, reduced larval food and high density can make adults more susceptible to infection. Fleas (Siphonaptera), like mosquitoes, go through complete metamorphosis and have adult stages that exclusively feed on the blood of vertebrates, including humans. However, flea larvae have chewing mandibles and rely on nutrients from dried fecal matter containing vertebrate blood proteins. Their limited mobility and unique nutritional needs confine their development to specific areas, likely leading to frequent larval competition in natural conditions. Yet, the influence of larval density on the …

Apobec3 Regulation By Thyroid Hormone, Michelle Santiago

All Graduate Theses, Dissertations, and Other Capstone Projects

Thyroid hormone (TH) is crucial for many biological processes, including the development of the auditory system. Appropriate thyroid hormone signaling is important for the development of the cochlea, leading to the successful onset of hearing. More specifically, TH influences the timing of remodeling of the greater epithelial ridge (GER), a transient cochlear structure that secretes proteins that contribute to the formation of the tectorial membrane. Developmental hypothyroidism results in delayed GER regression, whereas excess TH results in premature remodeling. Both conditions result in deafness. However, it is unknown how TH mediates GER remodeling. Expression profiling identified APOBEC3 (A3) as a …

Exploring The Molecular Basis Of Touch: A Comparative Analysis Of Gene Expression In Sensory Corpuscle-Rich And Corpuscle-Poor Skin Regions In The Duck, Thomas Hart

Theses and Dissertations--Biology

Cutaneous touch is facilitated by discrete cellular complexes composed of non-neuronal cells associated with mechanoreceptor neuron endings. The non-neuronal cells of these cutaneous end organ complexes (CEOCs) are believed to contribute to touch, but their role in touch sensation remains unclear. To better understand the function of CEOC cells, we sought to characterize the transcriptional profile of CEOC-rich tissue and identify genes expressed in CEOC cells. Bill skin of the tactile foraging Pekin duck (Anas platyrhynchos) is dense with CEOCs, specifically the avian analogs of mammalian Pacinian and Meissner corpuscles, while corpuscles in duck foot skin are scarce. Using RNA …

Neural Crest Cell Migration And Developmental Origin Of Bony Scutes In White Sturgeon (Acipenser Transmontanus), Melody Tew

Cal Poly Humboldt theses and projects

Neural crest cells (NCCs) and mesodermal somites independently produce embryonic mesenchyme as a precursor to the chondrocytes and osteocytes of the vertebrate skeleton. In mammals and teleosts, NCCs only contribute to the dermal cranial skeleton, while the mesodermal somites and lateral plate mesoderm form the entire dermal and endochondral postcranial skeleton. In sharks, NCCs contribute to both the cranial and trunk integumentary skeleton. This suggests that contribution of the trunk neural crest mesenchyme to the integumentary skeleton was an ancestral condition for all vertebrates that was lost over evolutionary time in the osteichthyan lineage, but the evolutionary timing of this …

Elucidation Of The Role Of Agouti-Signaling Protein Throughout Folliculogenesis And Early Embryonic Development In Cattle, Heather L. Chaney

Graduate Theses, Dissertations, and Problem Reports (ETD)

The oocyte expresses certain genes during folliculogenesis to regulate the acquisition of oocyte competence. Oocyte competence, which refers to the presence of imperative molecular factors in the oocyte that are critical for high oocyte quality, is directly related to the ability of the oocyte to result in a successful pregnancy following fertilization. Over the past few decades, the development and optimization of assisted reproductive technologies, particularly in vitrofertilization, have enabled the beef and dairy industries to advance cattle genetics and productivity. However, only approximately 40% of bovine embryos will develop to the blastocyst stage in vitro. In addition, bovine embryos …

The Investigation Of Novel Bovine Oocyte-Specific Long Non-Coding Rnas And Their Roles In Oocyte Maturation And Early Embryonic Development, Jaelyn Zoe Current

Graduate Theses, Dissertations, and Problem Reports (ETD)

Early embryonic loss is a significant factor in livestock species' infertility, resulting in an economic deficit. In cattle, the in vivo fertilization rate is ~90%, with an average calving rate of about 55%, indicating an embryonic-fetal mortality rate of roughly 35%. Further, 70-80% of total embryonic loss in cattle occurs during the first three weeks after insemination, particularly between days 7-16. Growing evidence indicates that the oocyte plays an active role in regulating critical aspects of the reproductive process required for successful fertilization, embryo development, and pregnancy. However, defining oocyte quality remains enigmatic. Recently, many have abandoned the notion that …

Knockout Of Endospanin 1 Via Crispr In Zebrafish, Danio Rerio, Jared Kittinger

Williams Honors College, Honors Research Projects

I made endospanin 1 knockout (KO) zebrafish to examine its effects on lipid and bone metabolism. Endospanin 1, or leptin receptor overlapping transcript (leprot), is a cytosolic protein linked to the protein hormone leptin that influences the trafficking of leptin receptors to the plasma membrane of cells. Genes for endospanin and tyrosinase (a pigmentation enzyme) were targeted via a microinjection of guide RNAs and CRISPR Cas9 into zebrafish embryos at 2-4 cell stages. I was able to disrupt the endospanin 1 gene (based upon the disruption of tyrosinase), but very few mutant zebrafish fully developed into adults. Only low KO …

Dysregulated Polycomb Repressive Complex 2 Contributes To Chronic Obstructive Pulmonary Disease By Rewiring Stem Cell Fate, Aria Byrd, Xufeng Qu, Alexsandr Lukyanchuk, Jinpeng Liu, Fan Chen, Kassandra J. Naughton, Tanner Ducote, Xiulong Song, Hannah Bowman, Yanming Zhao, Abigail R Edgin, Chi Wang, Jinze Liu, Christine Fillmore Brainson

Markey Cancer Center Faculty Publications

Aberrant lung cell differentiation is a hallmark of many lung diseases including chronic obstructive pulmonary disease (COPD). The EZH2-containing Polycomb Repressive Complex 2 (PRC2) regulates embryonic lung stem cell fate, but its role in adult lung is obscure. Histological analysis of patient tissues revealed that loss of PRC2 activity was correlated with aberrant bronchiolar cell differentiation in COPD lung. Histological and single-cell RNA-sequencing analyses showed that loss of EZH2 in mouse lung organoids led to lowered self- renewal capability, increased squamous morphological development, and marked shifts in progenitor cell populations. Evaluation of in vivo models revealed that heterozygosity of Ezh2 …

Tgif1 Physiological Levels Limit Β-Cell Distress And Neonatal Diabetes, Creighton J. Friend

Theses and Dissertations

TGIF1 belongs to the superfamily of homeodomain proteins, which regulate a wide variety of biological functions, including cell stemness and specification of cell fate during early development. Perhaps surprisingly, we found that enforced expression in pancreatic progenitor cells during embryogenesis resulted in severe diabetes, hinting at the possibility that TGIF1 might regulate pancreas development. Subsequent genetic experiments targeting β-cells showed that TGIF1 affected β-cell function and homeostasis. Transcriptomic analysis revealed that TGIF1 expression inhibits the expression of essential components of UPR signaling, underscoring a potential mechanism in which TGIF1 disrupts protein folding and secretion. Congruently, TGIF1 expression led to a …

Investigation Of The Segment Polarity Network In The Tardigrade Hypsibius Exemplaris, Taylor R. Harrison

UNF Graduate Theses and Dissertations

Segmentation has facilitated the evolution of the many forms of the panarthropods. Downstream regulation of segmentation is controlled by the highly conserved segment polarity network which includes the genes engrailed (en), hedgehog (hh), wingless (wg), cubitus interruptus (ci), patched (ptc), and smoothend (smo). While a high level of conservation has been seen in both the arthropods and onychophorans, only en has been described in any representatives of Tardigrada. Previous work had already established the loss of wg, which encodes for a Wnt ligand, in the tardigrade H. exemplaris …

Therapies For Mitochondrial Disorders, Kayli Sousa Smyth, Anne Mulvihill

SURE Journal: Science Undergraduate Research Experience Journal

Mitochondria are cytoplasmic, double-membrane organelles that synthesise adenosine triphosphate (ATP). Mitochondria contain their own genome, mitochondrial DNA (mtDNA), which is maternally inherited from the oocyte. Mitochondrial proteins are encoded by either nuclear DNA (nDNA) or mtDNA, and both code for proteins forming the mitochondrial oxidative phosphorylation (OXPHOS) complexes of the respiratory chain. These complexes form a chain that allows the passage of electrons down the electron transport chain (ETC) through a proton motive force, creating ATP from adenosine diphosphate (ADP). This study aims to explore current and prospective therapies for mitochondrial disorders (MTDS). MTDS are clinical syndromes coupled with abnormalities …

Omics Analysis In Cancer And Development, Emalie J. Clement

Theses & Dissertations

Advancements in next-generation sequencing technologies have made omics technologies accessible to more researchers and large omics datasets are becoming more common in biological research. Omics technologies, including genomics, transcriptomics, proteomics, and metabolomics, have been pivotal in our current understanding of development, how developmental defects can lead to cancer, and importantly, our approach to chemotherapeutic treatment for cancer patients. This dissertation describes two projects using both experimental and omics technologies to investigate molecular mechanisms in Pancreatic Ductal Adenocarcinoma (PDAC) and mammary gland development.

Pancreatic Ductal Adenocarcinoma (PDAC) is a devastating disease that is difficult to treat with current therapies. Subtyping PDAC …

Establishing The Efficacy Of Non-Cellular Components Of Adipose-Derived Stromal Vascular Fraction In Promoting Angiogenesis., Daniel Benson

Electronic Theses and Dissertations

Microvascular disease is hallmarked by pathophysiological conditions such as endothelial senescence, intimal thickening which impairs vasodilation, and regression of the capillary beds causing tissue ischemia in the myocardium or in peripheral vascular networks. Adipose-derived stromal vascular fraction (SVF) has previously demonstrated the ability to revascularize tissue. Increasing evidence shows that regenerative cells elicit their therapeutic benefit by paracrine mechanisms, leaving open extracellular vesicles (EVs) as a potential crux of the cell therapy paradigm. To test this idea, three types of gelatin methacrylate hydrogels were employed: SVF gels, EV gels derived from SVF, and blank control gels, which were used in-vitro …

Developmental Effects Of Chronic Low-Level Arsenic Exposure In Mouse Embryonic Stem Cells And In Human Induced Pluripotent Stem Cells, M. Chiara Perego

All Dissertations

Arsenic is an environmental contaminant commonly found in food and drinking water. Exposure to arsenic during embryonic development has been linked to reduced muscle growth, disrupted muscle development and locomotor activity, impaired neurodevelopment, reduced IQ, impaired memory and learning deficits. While the mechanisms responsible for developmental changes following in utero exposure to arsenic are not well known, one possibility is that arsenic might disrupt proper cellular differentiation. Therefore, we aimed to investigate the mechanisms by which arsenic exposure could alter stem cell differentiation into neurons.

First, we continuously exposed P19 mouse embryonic stem (ES) cells to 0.1 μM (7.5 ppb) …

The Adar-Mavs Pathway Is A Critical Mediator Of The Innate Immune System In Pancreatic Development And Cancer, Dhwani Rupani

Dissertations and Theses (Open Access)

Adenosine deaminase acting on RNA (ADAR) is an RNA-binding protein that deaminates adenosine (A) to inosine (I). A-to-I editing is an important post-transcriptional mechanism to prevent recognition of endogenous RNA by MDA5, a cytosolic RNA sensor. Activation of MDA5 by viral RNA can stimulate the innate immune system. Thus, ADAR-mediated RNA editing is crucial to distinguish “self” from “non-self”. ADAR has an important role in gene regulation as A-to-I editing alters RNA processing affecting both RNA and protein abundance. Given its importance in regulating innate immunity and transcript abundance, aberrations in Adar expression are implicated in developmental deformities and carcinogenesis. …

Light And Temperature Entrainment Of Two Circadian-Driven Behaviors In The Flesh Fly Sarcophaga Crassipalpis, Raven Ragsdale

Electronic Theses and Dissertations

Circadian rhythms dictate the timing of both once-in-a-lifetime adult emergence (eclosion) and daily locomotor activity rhythms in the flesh fly S. crassipalpis. Light cycles are considered the primary environmental time cue (zeitgeber), but the life history of S. crassipalpis suggests that temperature cycles (thermocycles) may also play a key role. This work evaluates the efficacy of thermocycling as a zeitgeber in S. crassipalpis. We found that shifting both light and temperature cycles of sufficient amplitude affect the phasing of eclosion and locomotor activity, but result in different patterns. Additional experiments suggest greater thermocycle sensitivity during the late metamorphic …

The Role Of Akirin/Nurd Interactions During Heart Development, Mia Jones

Symposium of Student Scholars

Congenital heart defects are often identified during pregnancy or infancy and are the most common birth defect presented in humans, affecting blood circulation resultant from small holes in a blood chamber to deformity-inducing missing structures. Recent advancements in medicine have allowed those affected to live healthier, longer lives. Gene combinations and chromosomal changes play pivotal roles in congenital heart defects, but the specific genes involved remain unknown. The Nowak Lab has discovered several novel regulatory proteins that are critical for embryonic heart development and is studying them for a potential link to congenital heart defects.

During embryogenesis, the heart of …

Regulation Of Tissue Mechanics And Adherens Junctions By Small Gtpase Rhoa During Drosophila Embryogenesis, Hanqing Guo

Dartmouth College Ph.D Dissertations

Actomyosin contractility plays an important role at both the cell and tissue level during developments. In this study, we developed an optogenetic tool that can acutely inhibit actomyosin contractility by targeting its main activator Rho1. This optogenetic tool can achieve myosin inhibition within one minute and thus enable further dissection of actomyosin function in development. In my first two projects, I used Drosophila mesoderm invagination (also known as ventral furrow formation) as a model to study epithelial folding, a fundamental mechanism for constructing complex 3D tissues. Apical constriction mediated by actomyosin contractility is a common mechanism for epithelial folding. However, …