Life Sciences Commons^™

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 …

Roles Of Autism Gene Arid1b In Murine Brain Development And Behavior, Amanda L. Smith

Theses & Dissertations

Autism spectrum disorder (ASD) and intellectual disability (ID) are highly prevalent neurodevelopmental disorders characterized by social and communication deficits, stereotyped behaviors, cognitive dysfunction, and deficits in adaptive behaviors. The pathogenesis underlying these disorders remains unknown, and thus no pharmacologic or genetic therapies are currently available. Recent progress in the field has shown that haploinsufficiency of the AT-rich interactive domain-containing 1B (ARID1B) gene is a genetic cause of ASD and ID. Our lab recently developed an Arid1b knockout mouse model to better study its role in the pathogenesis of these disorders. One theory regarding the cause of neurodevelopmental disorders …

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

University of 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 …

An Evolving Epigenome That Determines Tissue And Cell Specificity, Renee Louise Sears

Arts & Sciences Electronic Theses and Dissertations

Understanding the mechanisms driving phenotypic variation is a major goal of biology that unifies classical genetics with the emerging fields of genomics and epigenomics. Human and mouse share over 90% of genes and global tissue-specific patterns of expression are maintained between the species. Thus, it is hypothesized that gene expression is influenced through distinctive regulation among species in order to account for the unmistakable phenotypic divergence. DNA methylation, histone modifications, open chromatin patterns, transcription factor binding, and other epigenetic factors are all associated with shaping, maintaining, and repressing regulatory regions which in turn coordinate gene expression. It is vital to …

Maternal Immunity: Preimplantation Preparation And Spatial Distribution Of Ccl19, Ashleigh Elbert

Electronic Theses & Dissertations

Maternal Immunity: Preimplantation preparation and the role of CCL19

An Abstract of the thesis by

Ashleigh R. Elbert

The maternal uterus in mammals undergoes extensive remodeling in preparation for implantation of the semi-allogenic embryo. Activation of the T cell homing receptor, CCR7, regulates multiple aspects of adaptive immunity. Genetic deletion of CCR7 reduces T regulatory (T Reg) cell migration into mouse uteri and decreases embryo implantation. CCL19 and CCL21 are the sole ligands for CCR7. It is hypothesized that CCL19 expression could attract T reg cells into the pre-implantation uterus and provide local immune suppression prior to implantation. Sprague Dawley …

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.

Recruitment Of Polycomb-Group Proteins At Giant In Drosophila Embryos, Elnaz Ghotbi Ravandi

Biological Sciences Theses and Dissertations

Polycomb Group (PcG) proteins are evolutionarily conserved epigenetic transcriptional regulators that maintain the transcriptional repression of silenced genes. PcG mediated silencing is divided into two phases: initiation and maintenance. During the initiation phase, PcG proteins initially recognize and bind to their target genes. Once PcG proteins are recruited to their target genes, they can maintain transcriptional repression through an unlimited number of cell cycles. Most studies on PcG proteins have been focused on the maintenance phase of PcG silencing, and the molecular mechanisms by which PcG proteins are initially recruited to their target genes remained unknown. Two models have been …

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 …

The Role Of Xenopus Laevis Reck In Ecm Remodeling And Tissue Patterning, Jessica Willson

Electronic Thesis and Dissertation Repository

Proper cell-cell and cell-extracellular matrix (ECM) interactions are vital for cell migration and patterning of the vertebrate embryo. Matrix metalloproteinases (MMPs) and their inhibitors, reversion-inducing cysteine-rich proteins with Kazal motifs (RECK) and tissue inhibitors of metalloproteinases (TIMPs), are all differentially expressed during embryogenesis to regulate such ECM remodeling events and cell interactions. While TIMPs are a family of 4 secreted proteins that share overlapping substrate specificities of MMPs, RECK is unique in that it is a membrane-anchored MMP inhibitor that is embryonic lethal in mice. I used Xenopus laevis as a model organism to investigate the role of RECK as …

Investigating The Role Of Lbh During Early Embryonic Development In Xenopus Laevis, Emma Weir

Masters Theses

LBH is a highly conserved protein whose role during vertebrate development is relatively under-studied. In collaboration with the Albertson lab, our lab has previously shown that it is necessary for cranial neural crest cell migration in the zebrafish and in Xenopus laevis. The molecular mechanisms through which it acts are not well understood.

In Xenopus, LBH is a maternally deposited protein. As such, studying its role in early development has not been feasible through the morpholino-mediated knockdown techniques that prevent translation of target genes. Recently, a technique for degrading endogenous proteins was developed, called Trim-Away. This was developed in mammalian …

Patterns Of Morphological Plasticity In Metriaclima Zebra And Danio Rerio Suggest Differently Canalized Phenotypes Due To Form-Function Relationships, Dylan Jockel

Masters Theses

In order to ascertain the degree of compatibility in developmental restructuring and behavioral plasticity between two fish species frequently made subject of laboratory research (Metriaclima zebra & Danio rerio), alternative trophic niche exposure experiments utilizing novel three-prong feeding treatments were conducted to obtain morphometric data, which demonstrated both species do bear some degree of plasticity. The results are somewhat complicated by differences in locality of detectable restructuring, which may be due to disparity in the form-function relationship for each species’ lineage. Each is notable in the manner of respective species’ jaw protrusion, as it is driven by anterior …

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 …

Understanding The Transcriptional Mechanisms Underlying Dendritic Cell Development, Prachi Bagadia

Arts & Sciences Electronic Theses and Dissertations

Dendritic cells (DCs) comprise an important immune lineage that plays a critical role in initiating and sustaining the proper immune response. They can be divided into two distinct branches, classical/conventional DCs (cDCs) or plasmacytoid DCs (pDCs). cDCs can further be classified as cDC1 or cDC2. Each DC subset exerts unique functions in vivo and are necessary for a complete immune response. The precise transcriptional programs underlying DC specification and commitment remain unclear. cDC1, cDC2, and pDC all arise from the common DC progenitor (CDP) in the bone marrow. How the CDP gives rise to all three DC subsets in an …

From Single Cells To Human Disease: High-Resolution Phenotyping Of Male Infertility Models Using Single-Cell Rna Sequencing, Min Jung

Arts & Sciences Electronic Theses and Dissertations

Male infertility is a complex disease that can result in significant emotional distress and treatment costs. Globally, male infertility affects 7% of males, and while its incidence is rising, its etiology remains elusive. In order to improve patient care, it is critical to identify the nature of spermatogenic failure in as many men as possible. The extensive cellular heterogeneity of testis has limited the application of bulk expression measurements to capture crucial information to dissect molecular mechanisms of defects in the infertile patients. Thus, the application of single-cell RNA-sequencing on male germ cells provides an amazing new set of scientific …

Aging Of The Reproductive System And Of Germline Stem Cells In Caenorhabditis, Zuzana Kocsisova

Arts & Sciences Electronic Theses and Dissertations

C. elegans hermaphrodites display dramatic age-related decline of reproduction early in life while somatic functions are still robust. To understand why the germline fails so early, we analyzed the assembly line of oocyte production that generates fertilized eggs in mated hermaphrodites with sufficient sperm. Aging germlines displayed both sporadic and population-wide changes. A small fraction of aging animals displayed endomitotic oocytes in the germline and other defects. By contrast, all animals displayed age-related decreases in germline size and function. As early as day 3 of adulthood, animals displayed fewer stem cells and a slower cell cycle, which combine to substantially …

Mesothelium-Derived Factors Shape Tissue Resident Macrophage, Chin-Wen Lai

Arts & Sciences Electronic Theses and Dissertations

The studies outlined in this thesis provide several new insights into Msln-related pathways necessary for peritoneal immune responses and mucosal repair. We found that Msln and its binding partner mucin 16 from mesothelium influenced peritoneal and pleural macrophage differentiation. We found that Msln was required for proper tissue repair after colonic biopsy injury and was required for maximal polyp growth in APCMin/+ mice. Overall, this work describes mesothelial and epithelial-derived factors that are important for tissue resident macrophage differentiation and wound repair after colonic mucosal injury. Understanding the complex interactions between stromal cells and immune cells will lead to better …

Cyanogenesis And The Genetics Of Local Adaptation In White Clover (Trifolium Repens L.), Sara Jeanes Wright

Arts & Sciences Electronic Theses and Dissertations

Geographically widespread species experience varied selection across their ranges, and adaptation to local environments plays a critical role in their ability to persist. Understanding the genetic basis of local adaptation is a longstanding goal in evolutionary biology and provides practical information for agriculture and conservation. However, the genetic architecture of local adaptation has been characterized in relatively few plant species, primarily those with short lifespans and high rates of self-fertilization. Moreover, for plants, chemical defenses are known to play an important role in adaptation, but the extent to which they contribute to local adaptation is less understood. This dissertation provides …

A Role For Shh And Bmp4 In Regulating The Dorsal-Ventral Patterning Of The Developing Pharyngeal Region, Alex Szpak

Electronic Thesis and Dissertation Repository

The pharynx is crucial to the survival of all vertebrates since it facilitates respiration by connecting the nasal and oral cavity to the larynx and digestion by connecting the oral cavity to the esophagus. The developing pharyngeal region displays dorsoventral patterning, and currently there is little information identifying the underlying mechanisms that regulate this patterning. This is in part due to the complexity of the developing pharyngeal region that requires contributions from all three germ layers along with neural crest cells. The expression profiles of Sonic Hedgehog (Shh) and Bone Morphogenetic Protein 4 (Bmp4) adjacent to the developing pharyngeal region …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

The Influence Of Mir-322 On Skeletal Muscle Differentiation, Miles Alexander Soyer

Legacy Theses & Dissertations (2009 - 2024)

Skeletal muscle plays a crucial role in coordinating voluntary movement and accounts for nearly 50% of total body mass. Dysregulation in skeletal muscle development is known to cause muscle degenerative diseases including the devastating Duchenne Muscular Dystrophy (DMD). The majority of the biological studies investigating muscle development were based on myogenic transcription factors and signaling molecules including: Pax7, Myf5, MyoD, WNT, TGF-β and BMP. After the discovery of non-coding RNAs including microRNAs, it was postulated that these molecules could regulate gene expression and thus affect differentiation and development. MicroRNAs are small non-coding RNAs (~17-25 nucleotides) that regulate gene expression negatively …

Understanding The Molecular And Cellular Functions Of Odd-Skipped Related 1 In Outflow Tract Development, Menglan Xiang

Theses and Dissertations

The cardiac outflow tract (OFT) is a transient conduit that connects the embryonic heart chambers to the vascular network. Transcription factor Osr1 promotes the proliferation and cell cycle progression of second heart field (SHF), an essential cell population that contribute to the developing OFT. In this study, we investigated the role of Osr1 in OFT development on cellular and molecular levels using a systems biology approach. We observed OFT rotation and elongation defects, as well as double-outlet right ventricle and overriding aorta as a result of SHF-specific deletion of Osr1. Using genetic inducible fate mapping, we showed that Osr1-expressing SHF …

Pregestational Diabetes Induced Congenital Heart Defects And Coronary Artery Malformations; Mechanisms And Preventative Therapies, Anish Engineer

Electronic Thesis and Dissertation Repository

Congenital heart defects (CHDs) arise from perturbations in complex molecular and cellular processes underlying normal embryonic heart development. CHDs are the most common congenital malformation, occurring in 1 to 5% of live births, and are the leading cause of pediatric mortality. Adverse genetic and environmental factors can impede normal cardiogenesis and increase the likelihood of CHDs. Pregestational maternal diabetes increases the risk of CHDs in children by more than four-fold. As the prevalence of diabetes rapidly rises among women of childbearing age, there is a need to investigate the mechanisms and potential preventative strategies for these defects. The aim of …

Maternal Nicotine Exposure Induces Congenital Heart Defects In The Offspring Of Mice, Elizabeth Greco

Electronic Thesis and Dissertation Repository

Congenital heart defects are the most prevalent birth defect, and maternal cigarette smoking is a known risk factor. Nicotine replacement therapies are recommended to pregnant women who smoke to aid in smoking cessation, as this alternative is thought to be much safer compared to cigarette smoking. However, these products contain nicotine, and the safety of nicotine on the developing heart is not well known. In this thesis, a mouse model was used to test the hypothesis that maternal nicotine exposure (MNE) during pregnancy leads to congenital heart defects and coronary artery defects in the offspring of mice. MNE resulted in …

Absence Of Activating Transcription Factor 3 Reduces Severity Of Recurrent Pancreatitis And K-Ras Mediated Pdac In Mice, Nawab Azizi

Electronic Thesis and Dissertation Repository

Pancreatic ductal adenocarcinoma (PDAC) is a terminal cancer projected to become the leading cause of cancer-related deaths in North American by the year 2030. Constitutive activation of KRAS is seen in >90% of PDAC cases. In addition to oncogenic KRAS activity, pancreatic injury is key contributor to PDAC initiation and progression. Activating transcription factor 3 (ATF3) is required for the formation of pre-neoplastic lesions in acute pancreatitis. However, unlike recurrent or chronic forms of pancreatitis, acute pancreatitis is not predictive of PDAC. Therefore, the goal of this thesis is to determine the role of ATF3 in recurrent pancreatitis and PDAC. …

Oleic Acid Attenuates Palmitic Acid-Induced Impairments In Mouse Blastocyst Development, Maisoon Dafalla Yousif

Electronic Thesis and Dissertation Repository

Palmitic acid (PA) and oleic acid (OA) are the most abundant saturated and monounsaturated non-esterified fatty acids, respectively, in serum. The consequences of PA and OA treatment on preimplantation mouse embryo development were investigated. It was hypothesized that OA treatment from the two-cell stage onwards would attenuate PA-induced reductions in mouse blastocyst development. PA significantly reduced development to the blastocyst stage. Transcript analysis revealed that PA increased ER stress pathway markers activating transcription factor 3 and C/EBP homologous protein transcripts, and XBP1 splicing. Co-culture of PA-treated embryos with OA prevented this PA-induced ER stress and rescued blastocyst development. Cytoplasmic lipid …

Characterization Of Pth Type-2 Receptor ( Pth2rb ) And Its Endogenous Ligand Pth2 In Zebrafish Development, Nicholas Seitz

Theses and Dissertations

Members of the parathyroid hormone family of ligands, PTH (parathyroid hormone), PTH2, and PTHLH (parathyroid hormone-like hormone). These hormones interact with the class B GCPRs parathyroid hormone receptors PTH1R, PTH2R, and PTH3R to regulate a variety of biological processes. In mammals, PTH and PTHLH activate PTH1R and PTH3R to mediate serum calcium homeostasis, chondrogenesis, and bone maintenance. PTH2R activation by PTH2 has been studied primarily in regard to its neuroendocrine roles but is also found in the skin where it contributes to wound healing and keratinocyte differentiation. Still, little is known about the impacts of PTH2R signaling relative to PTH1R …

Effects Of Herbicides On Zebrafish Embryo Development And Viability, Kayla Ray King

MSU Graduate Theses

Environmental contaminants are chemicals of anthropogenic origin that are found in water, soil, and air, and are harmful to a wide variety of organisms (ORD US EPA, 2018-a). One common group of contaminants are herbicides. Though herbicides are used to control unwanted vegetation in agriculture, aquatic organisms and humans may be exposed to these herbicides through run off into streams and rivers, by drinking contaminated water, by consuming treated crops, by direct exposure, or through bioaccumulation. Thus the effect of these herbicides on animals needs further investigation. In this study, I sought to determine whether six different herbicides, which have …

Exploring Infant Leukemia Through Exome Sequencing And An In Vitro Model Of Hematopoietic Development, Mark Cannon Valentine

Arts & Sciences Electronic Theses and Dissertations

Cancer is a heterogeneous disease with myriad causes and outcomes. Many of the cancers that occur in adult populations have become increasingly well characterized with the advent of affordable high-throughput sequencing. These studies have revealed that cancer is largely a disease of somatic mutation in the adult population. In strong contrast to this, childhood cancers have an exceedingly low rate of somatic mutation. At the extreme end of this spectrum is Infant Leukemia (IL). Sequencing of IL has revealed that these tumors frequently have one or fewer somatic SNP. In the absence of a somatic explanation for IL, many other …

Muscle Degeneration In A Zebrafish Model Of Lysosomal Related Myopathy, Elizabeth Coffey

Electronic Theses and Dissertations

Muscle development and homeostasis are critical for normal muscle function. A key aspect of muscle physiology during development, growth and homeostasis is modulation of protein turnover. Protein turnover is the balance between synthesis and degradation of muscle proteins. The rate of protein degradation is the major factor underlying overall muscle growth during development. Protein degradation mainly takes place in the lysosome. The efficiency of lysosomal protein degradation depends upon lysosomal pH, which is generated and maintained by proton pumps. Despite the importance of protein degradation in muscle growth during development, the impact of dysregulated lysosomal pH on muscle development, growth, …

Phenotypic And Metabolic Plasticity In Canine Cellular Reprogramming, Ian C. Tobias

Electronic Thesis and Dissertation Repository

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) derived from large mammals reproduce few characteristics displayed by rodent or human counterparts. This is complicated by the inherent plasticity of mammalian ESC/iPSC cultures that resemble a variety of developmental stages including the naïve and primed pluripotent states. Defining the extrinsic signals that modulate the developmental identity of canine ESC/iPSC (i.e. primed versus naïve) will improve knowledge integration with more sophisticated rodent and primate research. In this thesis, I sought to determine if manipulation of the culture environment can promote nuclear and metabolic reprogramming of canine cell lines towards a …