Developmental Biology Commons^™

Functional Characterization Of Scaffold Protein Shoc2, Hyein Jang

Theses and Dissertations--Molecular and Cellular Biochemistry

Signaling scaffolds are critical for the correct spatial organization of enzymes within the ERK1/2 signaling pathway and proper transmission of intracellular information. However, mechanisms that control molecular dynamics within scaffolding complexes, as well as biological activities regulated by the specific assemblies, remain unclear.

The scaffold protein Shoc2 is critical for transmission of the ERK1/2 pathway signals. Shoc2 accelerates ERK1/2 signaling by integrating Ras and RAF-1 enzymes into a multi-protein complex. Germ-line mutations in shoc2 cause Noonan-like RASopathy, a disorder with a wide spectrum of developmental deficiencies. However, the physiological role of Shoc2, the nature of ERK1/2 signals transduced through this …

Zebrafish Model Of Mll-Rearranged Acute Myeloid Leukemia, Alex J. Belt

Theses and Dissertations

Acute myeloid leukemia (AML) is the second most common type of leukemia and accounts for 80% of adult acute leukemia cases and is characterized by the accumulation of poorly or undifferentiated myeloid blast cells. Standard treatment includes chemotherapy, which if unsuccessful, is followed by more rigorous chemotherapy as well as stem cell transplantation. Considering most patients are over the age of 45, these more rigorous therapies are not always possible, and as such, new therapies must be developed. Furthermore, AML patients harboring a chromosomal rearrangement involving Multiple Lineage Leukemia (MLL) that results in the expression of an MLL fusion protein …

Butyl Benzyl Phthalate (Bbp) Induces Caudal Defects During Embryonic Development, Nicole M. Roy, Ewelina Zambrzycka, Jenna Santangelo

Biology Faculty Publications

Butyl benzyl phthalate (BBP) is commonly added during the manufacturing of plastics to increase flexibility and elasticity. However, BBP leaches off of plastic and environment presence has been detected in soil, groundwater and sediment potentially effecting organisms in the environment. Given the widespread uses of BBP in household, consumer goods and the presence of BBP in the environment, studies on developmental toxicity are needed. Here, we use a zebrafish model to investigate the early developmental toxicity of BBP. We treated gastrula staged embryos with increasing concentrations of BBP and noted concentration-dependent defects in caudal tail development, but the effect was …

Optimizing Sperm Collection Procedures In Zebrafish, Madelyn B. Wasden, Rachel L. Roberts, April Delaurier

Journal of the South Carolina Academy of Science

Zebrafish are a highly-valued model organism used for developmental biology research. Zebrafish can be used for genetic manipulation and hence, many mutant and transgenic lines exist. It is impractical to maintain lines of adult zebrafish, due to resource constraints and the need to continuously produce new generations. Therefore, a practical way to preserve zebrafish lines is to freeze sperm and retrieve lines using in vitro fertilization of fresh eggs. Most existing in vitro protocols used by research labs have a wide variety of fertilization rates (ranging from 0% to >90%). Due to this variability, lines may be at risk of …

Platelet Derived Growth Factor Receptor B (Pdgfrb) Expressing Cells During Zebrafish Coronary Vessel Development, Juancarlos Fierros

Electronic Theses, Projects, and Dissertations

Coronary heart disease is a prevalent issue in developed countries throughout the world. It can have crippling effects on the quality of life and even lead to mortality, in the case of myocardial infarction. Part of the problem is the lack of a robust regenerative response in mammals after injury. Zebrafish have an amazing ability to regenerate after injury, and studies have demonstrated that the regenerative response recapitulates embryonic development. Our lab previously reported the first analysis of coronary vessel development in zebrafish and demonstrated that coronary endothelial cells undergo angiogenesis to form a vascular network. The roles of perivascular …

Ca2+/Calmodulin-Dependent Protein Kinase Type Ii (Camk-Ii) Is Required For Hematopoietic Stem Cell Specification, Camden E. Kurtz

Theses and Dissertations

Ca2+/Calmodulin-dependent protein kinase type II (CaMK-II) is a Serine/Threonine protein kinase that is activated by Ca2+ and Calmodulin to phosphorylate substrates involved in myriad developmental processes. This project implicates CaMK-II in specification of HSCs, and zebrafish provide an ideal embryonic model to study hematopoiesis. Zebrafish genetic manipulation was achieved through: incubation in chemical inhibitors; injection of notochord-targed WT and DN CaMK-II constructs with Transposase; and injection of camk2g1 translation-blocking morpholino antisense oligonucleotide (MO). Whole-mount in situ hybridization (WISH) and immunolocalization on zebrafish embryos allowed visualization of key HSC markers and pathway components that implicated CaMK-II in the specification of HSCs. …

Zebrafish (Danio Rerio) As A Model For Orofacial Research, Kevin A. Ghaffari

Theses and Dissertations

Across species, the face and more specifically the mouth, serves as an essential facet of everyday life. Amongst humans the mouth serves as a tool for the ingestion of food, a marker for facial recognition and a medium for communication. In order for the mouth to properly form, a series of precise growth and fusion events are needed. In order to insure that these events are orchestrated properly is a wide array of signals, transcription factors and epigenetic regulators. Due to the needed precision of these events, congenital birth defects of the face such as cleft lip and cleft palate …

Developmental Toxicity Of Tetrakis (Hydromethyl) Phosphonium Chloride (Thpc) In Zebrafish (Danio Rerio) Embryos, Lan L. Nguyen

Honors College Theses

Tetrakis (hydromethyl) phosphonium chloride (THPC) is a tetrakis (hydromethyl) phosphonium salt commonly used by the textile industry and is polymerized onto cotton fabrics to provide a flame-retardant finish. Traces of THPC were found in the Ogeechee River, a 294 mile-long black river in Georgia, and could have been a toxin contributing to the mass killing of aquatic animals in May 2011. THPC has been known to be carcinogenic and cause other systemic toxicity in various mammalian animals. However given that the chemical is mostly discharged in natural waters, the environmental impact of the discharge on water quality and there by …

Dual Functions For Insulinoma-Associated 1 In Retinal Development, Marie A. Forbes-Osborne

Theses and Dissertations--Biology

Proper visual system function requires tightly controlled proliferation of a pool of relatively homogeneous retinal progenitor cells, followed by the stepwise specification and differentiation of multiple distinct cell types. These retinal cells, both neuronal and glial, must be generated in the correct numbers, and the correct laminar location to permit the formation of synaptic connections between individual cell types. After synapses are made, constant signaling is required as part of normal retinal function, and to maintain cellular identity and connectivity. These processes rely on both extrinsic and intrinsic signaling, with regulation of gene expression by cascades of transcription factors having …

Myosinx Is Required For Craniofacial Development In Danio Rerio, Cole Yancey

College of Graduate Studies: Theses & Dissertations

Craniofacial development is the process of laying early cartilage and bone patterns in the anterior region of the embryo, which ultimately results in shaping the structure of the face and head of an organism. Craniofacial abnormalities in humans, such as cleft lip and palate, are among the most common of all birth defects. Therefore, investigating the molecular mechanisms involved in craniofacial development will help us understand both evolutionary processes and genetic diseases. Craniofacial cartilage and bone structures are almost entirely derived from neural crest cells. Neural crest are a pluripotent migratory stream of cells that originate from the early developing …

Myosin 10 Is Required For Spinal Motor Axon Growth And Guidance In Zebrafish Embryos, Crystal Ivey

College of Graduate Studies: Theses & Dissertations

Neurodevelopmental disorders are disabilities caused by malfunctioning mechanisms within the developing nervous tissue. These abnormalities often result in conditions such as autism spectrum disorders, Attention Deficient Hyperactivity Disorder (ADHD), motor dysfunctions, learning disabilities and mental retardation. Recent surveys indicate that there will be a 12% increase of children in the United States alone who are affected by neurodevelopmental disorders. Thus, it is important to understand both the normal and abnormal mechanisms of neural development. Neural development involves specification of new neurons and formation of neural circuits that connect the nervous system to every organ of the developing embryo. Neural circuits …

Characterization Of Adult Zebrafish Retinal Regeneration Following Two Different Damage Models, Jennifer Lee Thomas

Wayne State University Dissertations

Unlike mammals, zebrafish can regenerate all of their retinal neurons through Müller glial cells, which respond to retinal damage by re-entering the cell cycle to create clusters of progenitor cells. The progenitors continue to proliferate as they migrate to the site of damage, where they ultimately differentiate into new retinal neurons. In contrast, Müller glia of the mammalian retina respond to injury with reactive gliosis, which if persistent, can lead to loss of Müller cell function and devastating vision loss. Despite this, multiple lines of evidence suggest that mammalian Müller glial cells possess a latent ability to regenerate retinal neurons. …

Gene Discovery In Nonsyndromic Cleft Lip With Or Without Cleft Palate, Brett T. Chiquet

Dissertations and Theses (Open Access)

Nonsyndromic cleft lip with or without cleft palate (NSCLP), a common, complex orofacial birth defect that affects approximately 4,000 newborns each year in the United States, is caused by both genetic and environmental factors. Orofacial clefts affect the mouth and nose, causing severe deformity of the face, which require medical, dental and speech therapies. Despite having substantial genetic liability, less than 25% of the genetic contribute to NSCLP has been identified. The studies described in this thesis were performed to identify genes that contribute to NSCLP and to demonstrate the role of these genes in normal craniofacial development. Using genome …

Dynamic Glucoregulation And Mammalian-Like Responses To Metabolic And Developmental Disruption In Zebrafish, Agata Jurczyk, Nicole M. Roy, Rabia Bajwa, Philipp Gut, Kathryn Lipson, Chaoxing Yang, Laurence Covassin, Waldemar J. Racki, Aldo A. Rossini, Nancy Phillips, Didier Y. R. Stainier, Dale L. Greiner, Michael A. Brehm, Rita Bortell, Philip Diiorio

Biology Faculty Publications

Zebrafish embryos are emerging as models of glucose metabolism. However, patterns of endogenous glucose levels, and the role of the islet in glucoregulation, are unknown. We measured absolute glucose levels in zebrafish and mouse embryos, and demonstrate similar, dynamic glucose fluctuations in both species. Further, we show that chemical and genetic perturbations elicit mammalian-like glycemic responses in zebrafish embryos. We show that glucose is undetectable in early zebrafish and mouse embryos, but increases in parallel with pancreatic islet formation in both species. In zebrafish, increasing glucose is associated with activation of gluconeogenic phosphoenolpyruvate carboxykinase1 (pck1) transcription. Non-hepatic Pck1 protein is …

The Zebrafish As A Model Of Ventricular And Arterial Pole Malformations, Adrian Colin Grimes

MUSC Theses and Dissertations

The zebrafish is becoming an almost ubiquitously accepted model for the study of comparative developmental biology, its utility coming to rival that of the fruitfly, frog, chick and mouse. Unfortunately, however, it is widely held belief that the zebrafish cardiac outflow tract makes it unusual as a model of comparative cardiogenesis and this is based, in part, on the report that bulbus arteriosus undergoes a developmental myocardium-to-smooth muscle phenotypic transition. This would imply that the zebrafish may be poorly suited to the study of human cardiac outflow abnormalities. While the use of chamber-specific molecular markers has allowed extensive characterization of …