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2016

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Articles 1 - 30 of 171

Full-Text Articles in Cell Biology

Histone Deacetylase 3 Coordinates Heart Development Through Stage-Specific Roles In Cardiac Progenitor Cells, Sara L. Lewandowski Dec 2016

Histone Deacetylase 3 Coordinates Heart Development Through Stage-Specific Roles In Cardiac Progenitor Cells, Sara L. Lewandowski

GSBS Dissertations and Theses

Disruptions in cardiac development cause congenital heart disease, the most prevalent and deadly congenital malformation. Genetic and environmental factors are thought to contribute to these defects, however molecular mechanisms remain largely undefined. Recent work highlighted potential roles of chromatin- modifying enzymes in congenital heart disease pathogenesis. Histone deacetylases, a class of chromatin-modifying enzymes, have developmental importance and recognized roles in the mature heart. This thesis aimed to characterize functions of Hdac3 in cardiac development. We found loss of Hdac3 in the primary heart field causes precocious progenitor cell differentiation, resulting in hypoplastic ventricular walls, ventricular septal defect, and mid- gestational ...


The Fate Of Icd-1 During Misfolded Protein Induced Apoptosis In Caenorhabditis Elegans, Kyle H. Perez Dec 2016

The Fate Of Icd-1 During Misfolded Protein Induced Apoptosis In Caenorhabditis Elegans, Kyle H. Perez

Senior Honors Projects, 2010-2019

Severe misfolded protein stress initiates cellular responses that often result in the death of the affected cell, typically by apoptosis. An essential aspect of apoptosis is caspase-mediated cleavage of proteins that, once cleaved, further propagate death. One heterodimeric structure putatively targeted in this process in the nascent polypeptide-associated complex (NAC), a translational chaperone thought to help prevent misfolded protein stress in the ER. The purpose of this investigation was to determine whether the beta subunit of the NAC in C. elegans (ICD-1) is cleaved during the induction of apoptosis, with the hypothesis that ICD-1 is cleaved during stressed-induced apoptosis to ...


Mechanism Of Action Of Id4 As A Tumor Suppressor, Shravan Kumar Komaragiri Dec 2016

Mechanism Of Action Of Id4 As A Tumor Suppressor, Shravan Kumar Komaragiri

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

Initial studies demonstrated that Inhibitor of DNA binding/differentiation protein 4 (Id4) acts as a tumor suppressor in prostate cancer (PCa). To further confirm and investigate the mechanism by which ID4 acts as a tumor suppressor, herein we concentrated on two different approaches. In the first approach we investigated ID4 role as a tumor suppressor by regulating AKT/PI3K pathway. In the second approach, we examined the role of Id4 in blocking the tumorogenic properties of metastatic PC3 cells. Phosphoinositide 3-kinase/Protein kinase B (PI3/AKT) pathway regulates multiple biological processes leading to cell survival, proliferation and growth in cancerous ...


Id4 And Fkbp52 Interaction Regulates Androgen Receptor Activity: Mechanistic Insight, Jugal Bharat Joshi Dec 2016

Id4 And Fkbp52 Interaction Regulates Androgen Receptor Activity: Mechanistic Insight, Jugal Bharat Joshi

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

The inhibitor of DNA binding protein 4 (ID4) is a dominant negative regulator of basic helix loop helix (bHLH) family of transcription factors.1 Recently, Patel et al., demonstrated that inhibitor of differentiation 4 (ID4) acts as a tumor suppressor and its loss, frequently observed in prostate cancer, promotes castration-resistant prostate cancer (CRPC) through constitutive androgen receptor (AR) activation.2 However, the mechanism by which loss of ID4 promotes constitutively active AR signaling in the CRPC conditions is unknown. The rationale of the present study was to unravel the underlying molecular mechanisms through which loss of ID4 potentiates AR signaling ...


Evidence Of A Role For G Protein Signaling Modulator 3 In Cell Division, Drew C. Wallace Dec 2016

Evidence Of A Role For G Protein Signaling Modulator 3 In Cell Division, Drew C. Wallace

Electronic Thesis and Dissertation Repository

Components of G protein-mediated signaling are associated with positioning and orienting the mitotic spindle in the process of cell division. However, a functional role for G protein signaling modulator 3 (GPSM3) in cell division has yet to be defined. The purpose of this study was to investigate a potential role for GPSM3 in cell division. Vascular smooth muscle cells (VSMCs) from Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats, that are known to express GPSM3, were used as a model system. Here I report that GPSM3 mRNA and protein levels varied during different stages of the cell cycle in SHR VSMCs ...


The Origin Of Human White, Brown, And Brite/Beige Adipocytes, So Yun Min Dec 2016

The Origin Of Human White, Brown, And Brite/Beige Adipocytes, So Yun Min

GSBS Dissertations and Theses

During embryonic development, adipocytes emerge from microvasculature. Lineage-­‐tracing studies in mice have shown that adipocyte progenitors reside in the adipose tissue capillaries. However, the direct evidence of an association between adipocyte progenitors and vasculature in humans is lacking. A specific class of adipocytes (brown and beige/brite) expresses the uncoupling protein 1 (UCP1), which consumes glucose and fatty acids to generate heat. The abundance of UCP1- containing adipocytes correlates with a lean metabolically healthy phenotype in human. However, a causal relationship between the presence of these cells and metabolic benefits in human is not clear.

In this thesis, I ...


Defining The Role Of Phosphorylation And Dephosphorylation In The Regulation Of Gap Junction Proteins, Hanjun Li Dec 2016

Defining The Role Of Phosphorylation And Dephosphorylation In The Regulation Of Gap Junction Proteins, Hanjun Li

Theses & Dissertations

Gap junctions are intercellular channels that permit the free passage of ions, small metabolites, and signaling molecules between neighboring cells. In the diseased human heart, altered ventricular gap junction organization and connexin expression (i.e., remodeling) are key contributors to rhythm disturbances and contractile dysfunction. Connexin43 (Cx43) is the dominant gap junction protein isoform in the ventricle which is under tight regulation by serine/tyrosine phosphorylation. Phosphorylation and dephosphorylation regulate many aspects of Cx43 function including trafficking, assembly and disassembly, electrical and metabolic coupling at the plaque, as well as to modulate the interaction with other proteins.

Serine phosphorylation has ...


Regulation Of Alteration/Deficiency In Activation 3 (Ada3) By Acetylation And Its Role In Cell Cycle Regulation And Oncogenesis, Shashank Srivastava Dec 2016

Regulation Of Alteration/Deficiency In Activation 3 (Ada3) By Acetylation And Its Role In Cell Cycle Regulation And Oncogenesis, Shashank Srivastava

Theses & Dissertations

The ADA3 (Alteration/Deficiency in Activation 3) protein is a transcriptional adaptor protein that was initially discovered as a component of several HAT (Histone Acetyltransferase) complexes, the enzyme complex responsible for histone acetylation, which is a prerequisite for transcription. Earlier the studies from Dr. Band’s laboratory and that of others’ have deciphered a crucial role of ADA3 in cell cycle regulation (both through G1/S and G2/M phase transitions) and in maintaining the genomic stability.

While our laboratory investigated the mechanism behind the role of ADA3 in G1/S transition, the same remained unknown for ...


Mitogen And Morphogen Signaling Dysregulation: Pathophysiological Influence In Pancreatic Cancer And Alzheimer’S Disease, Eric Cruz Dec 2016

Mitogen And Morphogen Signaling Dysregulation: Pathophysiological Influence In Pancreatic Cancer And Alzheimer’S Disease, Eric Cruz

Theses & Dissertations

Although the etiology of a particular disease will vary, there are genetic and epigenetic bottlenecks that frequently converge resulting in dysregulation of mitogenic and morphogenetic signaling. This propensity is acutely experienced in malignancy and neurodegenerative disease.

Here, we have first investigated the role of dysregulated signaling in the context of pancreatic cancer (PC). Morphogenetic signaling has been regarded as a pleiotropic pathway with the potential to promote and inhibit metastatic features. Our investigation of bone morphogenetic protein 2 (BMP-2), an archetypical member of the BMP superfamily, has revealed the presence of extracellular, intracellular, and long non-coding RNA products. Our findings ...


The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai Dec 2016

The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai

Electronic Thesis and Dissertation Repository

Galectins are a group of β-galactoside-binding proteins involved in different cellular processes including stress responses and differentiation. The role and expression of galectins under oxidative stress and during neutrophilic differentiation was examined in HL-60 cells. Galectin gene (LGALS), and galectin protein expression were determined using RT-qPCR and immunoblotting, respectively. Neutrophilic differentiation was measured via a spectrofluorometric assay. DNA methylation and JNK signaling were investigated as galectin regulatory mechanisms. Menadione-induced oxidative stress, DMSO-induced differentiation, DNA hypomethylation and JNK signaling all promoted similar galectin expression profiles. Antioxidant N-acetylcysteine attenuated the menadione-induced galectin expression but only partially attenuated DMSO-induced galectin expression. Galectin inhibitory ...


Developing A Cr281 Peptide Specific T Lymphocyte Immune Response To Target Pancreatic Cancer Cck2i4sv Receptor, Taylor Hook Dec 2016

Developing A Cr281 Peptide Specific T Lymphocyte Immune Response To Target Pancreatic Cancer Cck2i4sv Receptor, Taylor Hook

Honors Projects and Presentations: Undergraduate

Pancreatic cancer is a debilitating disease with a poor survival rate. There are no effective treatments for pancreatic cancer necessitating research to find new targets for treatment. The basis of this research is to determine whether a novel target located inside of pancreatic cancer cells can be utilized to control or eradicate pancreatic tumors by T cell-based immunity. Gastrin and Cholecystokinin (CCK) are hormones that regulate activity of the gastrointestinal tract.Each can signal via CCK-BR, which normally acts as an on/off switch for pancreatic cells to secrete enzymes and bicarbonate. An altered form of the CCK-B receptor, CCK2i4sv ...


Cd4+ T Cell Regulation Of Immune Responses To The Simian Virus 40 Large Tumor Antigen Is Complex And Involves Multiple Layers Of Coordination Dependent On Immune Conditions, Arielle Raugh, Lawrence Mylin Dec 2016

Cd4+ T Cell Regulation Of Immune Responses To The Simian Virus 40 Large Tumor Antigen Is Complex And Involves Multiple Layers Of Coordination Dependent On Immune Conditions, Arielle Raugh, Lawrence Mylin

Honors Projects and Presentations: Undergraduate

Cytotoxic (CD8+) and Helper (CD4+) T lymphocytes play an important role in the immune detection and destruction of tumors. The induction of Cytotoxic T cell responses by multiple CD8 epitopes located within the Simian Virus 40 Large Tumor Antigen (SV40 T ag) oncoprotein has been well characterized, and we have begun to characterize the role(s) of CD4+ Helper T cells in controlling cellular immune responses to the SV40 T ag. The goal of this study was to characterize the cytokines produced by activated SV40T ag-specific Helper T cells in order to identify subset(s) of Helper T cells that ...


Insights Into The Role Of Connexin26 And Connexin30 In Skin Health, Syndromic Disease, And Cutaneous Wound Healing, Eric R. Press Dec 2016

Insights Into The Role Of Connexin26 And Connexin30 In Skin Health, Syndromic Disease, And Cutaneous Wound Healing, Eric R. Press

Electronic Thesis and Dissertation Repository

Connexin26 (Cx26) and Cx30 facilitate gap junctional intercellular communication (GJIC) in the epidermis and are linked to several syndromic skin diseases. We investigated 5 disease- linked Cx26 mutants and demonstrated that the severity and extent of disease can be predicted from the gain- or loss-of function properties of each mutant, as well as the ability to induce cell death. We also used transgenic mice expressing S17F Cx26 (linked to keratitis-ichthyosis- deafness syndrome) or A88V Cx30 (linked to Clouston Syndrome) to investigate the pathophysiology these skin diseases. We demonstrated that S17F Cx26, but not A88V Cx30, promotes palmoplantar keratoderma by disrupting ...


Molecular And Functional Analysis Of The Pixb Gene In Xenorhabdus Nematophila, John Lucas Dec 2016

Molecular And Functional Analysis Of The Pixb Gene In Xenorhabdus Nematophila, John Lucas

Theses and Dissertations

Xenorhabdus nematophila and the entomopathogenic nematode Steinernema carpocapsae form a mutualistic relationship facilitating the infection, death and consumption of an insect host. The infective juvenile (IJ) form of S. carpocapsae invades the insect host through natural openings and proceeds to the hemocoel where exposure to hemolymph stimulates the release of X. nematophila from the anterior vesicle. Excreted X. nematophila releases immunosuppressive compounds and insect toxins into the insect hemolymph that facilitates death of the host. As X. nematophila reaches high cell density it secretes exoenzymes that degrade insect tissues and produces antibiotics that reduce microbial competition. S. carpocapsae utilizes the ...


Ultrastructural Changes During Pollen Wall Development And Germination In Arabidopsis Thalaiana, Katrina Olsen Dec 2016

Ultrastructural Changes During Pollen Wall Development And Germination In Arabidopsis Thalaiana, Katrina Olsen

Theses and Dissertations

The Arabidopsis thaliana meiotic mutant 6491 has been identified as displaying temperature sensitive male reduced- fertility. It has been determined that callose wall formation is defective, both in temporal and structural areas. There is irregular rippling in the plasma membrane and aberrant formation of the exine portion of the pollen wall. A developmental study using brightfield, epifluorescence, and transmission electron microscopy of the early stages of wall formation in 6491 has been completed, along with a similar study of Arabidopsis thaliana (L.) heynh, ecotype Wassilewskija (WS). Due to the temperature-sensitive nature of the mutant line, a further study of both ...


Characterization Of Vesicular Monoamine Transporter 2 And Its Role In Parkinson's Disease Pathogenesis Using Drosophila, Antonio Joel Tito Jr., Sheng Zhang Dec 2016

Characterization Of Vesicular Monoamine Transporter 2 And Its Role In Parkinson's Disease Pathogenesis Using Drosophila, Antonio Joel Tito Jr., Sheng Zhang

UT GSBS Dissertations and Theses (Open Access)

Parkinson’s disease (PD) is a progressive neurodegenerative disorder caused by the selective loss of the dopaminergic neurons in the Substantia nigra pars compacta region of the brain. PD is also the most common neurodegenerative disorder and the second most common movement disorder. PD patients exhibit the cardinal symptoms, including tremor of the extremities, rigidity, slowness of movement, and postural instability, after 70-80% of DA neurons degenerate. It is, therefore, imperative to elucidate the underlying mechanisms involved in the selective degeneration of DA neurons. Although increasing numbers of PD genes have been identified, why these largely widely expressed genes ...


Using Mouse Models To Define How The P53 R72p Polymorphism Impacts The Adverse Effects Of Doxorubicin And Ionizing Radiation, Emily Dominguez Dec 2016

Using Mouse Models To Define How The P53 R72p Polymorphism Impacts The Adverse Effects Of Doxorubicin And Ionizing Radiation, Emily Dominguez

UT GSBS Dissertations and Theses (Open Access)

The single nucleotide polymorphism (SNP) at codon 72 of the tumor suppressor gene p53 codes for either an arginine (R) or proline (P) (p53 R72P). This SNP may impact how cells respond to genotoxic insult. Studies in cell culture and in tissues from mouse models of the SNP indicate that, in response to gentoxic treatment, the two variants may differentially induce apoptosis and expression of p53 target genes. In epidemiological studies, the P variant is associated with decreased cancer survival and increased risk of side-effects from genotoxic cancer treatment. Genotoxic therapy is still the mainstay of cancer treatment, and doxorubicin ...


Microenvironment-Induced Pten Loss By Exosomal Microrna Primes Brain Metastasis Outgrowth, Lin Zhang Dec 2016

Microenvironment-Induced Pten Loss By Exosomal Microrna Primes Brain Metastasis Outgrowth, Lin Zhang

UT GSBS Dissertations and Theses (Open Access)

Development of life-threatening cancer metastases at distant organs requires disseminated tumor cells’ adaptation to and co-evolution with the drastically different microenvironments of metastatic sites. Cancer cells of common origin manifest distinct gene expression patterns after metastasizing to different organs. Clearly, the dynamic interplay between metastatic tumor cells and extrinsic signals at individual metastatic organ sites critically impacts the subsequent metastatic outgrowth. Yet, it is unclear when and how disseminated tumor cells acquire the essential traits from the microenvironment of metastatic organs that prime their subsequent outgrowth. Here we show that primary tumor cells with normal expression of PTEN, an important ...


Influence Of Ph And Acidic Side Chain Charges On The Behavior Of Designed Model Peptides In Lipid Bilayer Membranes, Venkatesan Rajagopalan Dec 2016

Influence Of Ph And Acidic Side Chain Charges On The Behavior Of Designed Model Peptides In Lipid Bilayer Membranes, Venkatesan Rajagopalan

Theses and Dissertations

The molecular properties of transmembrane proteins and their interactions with lipids regulate biological function. Of particular interest are interfacial aromatic residues and charged residues in the core helix whose functions range from stabilizing the native structure to regulating ion channels. This dissertation addresses the pH dependence and influence of potentially negatively charged tyrosine, glutamic acid or aspartic acid side chains. We have employed GWALP23 (acetyl-GGALW5LALALALALALALW19LAGA-amide) as favorable host peptide framework. We have substituted W5 with Tyr (Y5GWALP23) and Leu residues with Glu (L12E, L14E or L16E) or Asp (L14D or L16D), and have incorporated specific 2H-labeled alanine residues within the ...


Exploring The Production Of Extracellular Matrix By Astrocytes In Response To Mimetic Traumatic Brain Injury, Addison Walker Dec 2016

Exploring The Production Of Extracellular Matrix By Astrocytes In Response To Mimetic Traumatic Brain Injury, Addison Walker

Theses and Dissertations

Following injury to the central nervous system, extracellular modulations are apparent at

the site of injury, often resulting in a glial scar. Astrocytes are mechanosensitive cells, which can create a neuroinhibitory extracellular environment in response to injury. The aim for this research was to gain a fundamental understanding of the affects a diffuse traumatic brain injury has on the astrocyte extracellular environment after injury. To accomplish this, a bioreactor culturing astrocytes in 3D constructs delivered 150G decelerations with 20% biaxial strain to mimic a traumatic brain injury. Experiments were designed to compare the potential effects of media type, number of ...


Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady Dec 2016

Effect Of Oxygen-Limiting Tidal Conditions On Muscle Metabolism And Structure In The Giant Acorn Barnacle, Balanus Nubilus, Katie O. Grady

Master's Theses and Project Reports

Crustacean muscle fibers are some of the largest cells in the animal kingdom, with fiber diameters in the giant acorn barnacle (Balanus nubilus) exceeding 3 mm. Sessile animals with extreme muscle sizes and that live in the hypoxia-inducing intertidal zone – like B. nubilus – represent ideal models for probing the effects of oxygen limitation on muscle cells. We investigated changes in metabolism and structure of B. nubilus muscle in response to: normoxic immersion, anoxic immersion, or air emersion, for acute (6h) or chronic (6h exposures twice daily for 2wks) time periods. Following exposure, we immediately measured hemolymph pO2, pCO2 ...


Ros Regulation Of Axonal Mitochondrial Transport, Pin-Chao Liao Dec 2016

Ros Regulation Of Axonal Mitochondrial Transport, Pin-Chao Liao

Open Access Dissertations

Mitochondria perform critical functions including aerobic ATP production and calcium (Ca2+) homeostasis, but are also a major source of reactive oxygen species (ROS) production. To maintain cellular function and survival in neurons, mitochondria are transported along axons, and accumulate in regions with high demand for their functions. Oxidative stress and abnormal mitochondrial axonal transport are associated with neurodegenerative disorders. However, we know little about the connection between these two. Using primaryDrosophila neuronal cell culture and the third instar larval nervous system as in vitro and in vivo models, respectively, we studied mitochondrial transport under oxidative stress conditions. In vitro ...


Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra Dec 2016

Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra

Open Access Dissertations

In alphaviruses the role of E3 is required in protecting the fusion peptide region of E1 during intracellular transport. Throughout viral processing, the association of E2 and E3 is required for the successful trafficking and incorporation of E1 into the mature virion. This E3-E2 association has been observed to extend to mature virions in the solved structure for the envelope of Semliki Forest virus (SFV) and supported by the solved structure for the entire Venezuelan equine encephalitis virion (VEEV) with exclusive contacts being made between E3-E2. Immunization with monoclonal antibodies against VEEV E3 provided protection for mice challenged by lethal ...


Generating Patient-Specific Induced Pluripotent Stem Cell-Derived Choroirdal Endothelium To Study And Treat Macular Degeneration, Allison Elaine Songstad Dec 2016

Generating Patient-Specific Induced Pluripotent Stem Cell-Derived Choroirdal Endothelium To Study And Treat Macular Degeneration, Allison Elaine Songstad

Theses and Dissertations

Age-related macular degeneration (AMD) is a leading cause of irreversible blindness in the Western world. Although, the majority of stem cell research to date has focused on production of RPE and photoreceptor cells for the purpose of evaluating disease pathophysiology and cell replacement, there is strong evidence that the choroidal endothelial cells (CECs) that form the choriocapillaris vessels are the first to be affected in this disease. As such, to accurately evaluate disease pathophysiology and develop an effective treatment, production of patient-specific stem cell-derived CECs will be required.

During the first stage of my Ph.D work, represented in Chapter ...


Graph Theory Analysis Of Single Cell Transcriptomes Define Islet Signaling Networks And Cell Identity, Scott Robert Tyler Dec 2016

Graph Theory Analysis Of Single Cell Transcriptomes Define Islet Signaling Networks And Cell Identity, Scott Robert Tyler

Theses and Dissertations

Several challenges face bioinformaticians on a regular basis. One of these is unsupervised clustering. In RNA sequencing (RNAseq), this may come in the form of blindly sequencing single cells without a priori knowledge of the cell types being sequenced. Here we create new methods to address this problem that show increased accuracy and speed compared to competing methods. We also have developed a methodology for discovering non-parametric networks which represent relationships between the variables that have been measured across samples. In the context of RNAseq, this is the expression relationships between genes (for example a positive or negative Spearman correlation ...


Dopamine Effects Of Stimulant And Non-Stimulant Drugs Used In The Treatment Of Attention Deficit Hyperactivity Disorder, Preeti Chalwadi Nov 2016

Dopamine Effects Of Stimulant And Non-Stimulant Drugs Used In The Treatment Of Attention Deficit Hyperactivity Disorder, Preeti Chalwadi

Theses and Dissertations

Attention deficit hyperactivity disorder (ADHD) is thought to be associated with dysfunction of ascending catecholamine neuronal systems, particularly dopamine (DA) and norepinephrine (NE). Dysfunction of these catecholamine neurons innervating the prefrontal cortex is hypothesized to underlie impaired executive functions. Dysfunction of the DA neurons innervating the striatum is additionally hypothesized to underlie deficits in motivation and reinforcement learning. However, mechanisms of action of therapeutic drugs used for treating ADHD have mainly focused on catecholamines in the prefrontal cortex and have not adequately addressed the role played by DA signaling in the striatum. Stimulants such as Adderall® and Ritalin® are chemically ...


Vdr-Ripk1 Interaction And Its Implications In Cell Death And Cancer Intervention, Waise Quarni Nov 2016

Vdr-Ripk1 Interaction And Its Implications In Cell Death And Cancer Intervention, Waise Quarni

Graduate Theses and Dissertations

Receptor interacting protein kinase 1 (RIPK1) is an enzyme acting downstream of tumor necrosis factor alpha to control cell survival and death. RIPK1 expression has been reported to cause drug resistance in cancer cells; but so far, no published studies have investigated the role of RIPK1 in vitamin D action. In the present study, we investigated whether RIPK1 played any role in 1,25-dihydroxyvitamin D3 (1,25D3)-induced growth suppression. In our studies, RIPK1 decreased the transcriptional activity of vitamin D receptor (VDR) in luciferase reporter assays independently of its kinase activity, suggesting a negative role of RIPK1 in 1 ...


The Cellular Context Of Estradiol Regulation In The Zebra Finch Auditory Forebrain, Maaya Ikeda Nov 2016

The Cellular Context Of Estradiol Regulation In The Zebra Finch Auditory Forebrain, Maaya Ikeda

Doctoral Dissertations

Estradiol, traditionally known as a hormone that communicates with distant cells in the body, is also synthesized locally in the brain to act as a neuromodulator. Neuromodulators differ from neurotransmitters in that they simultaneously affect a population of neurons and their actions are not limited to the synapse. One of the many effects of estradiol signaling is rapid modulation of auditory processing in response to external stimuli. The enzyme required for estradiol synthesis, aromatase, is highly expressed in the regions that are involved in higher-order processing of sounds in humans and songbirds. Since zebra finches, a type of songbird, are ...


Requirement And Function Of Hippo Pathway Signaling In The Mammalian Gastrointestinal Tract: A Dissertation, Jennifer L. Cotton Oct 2016

Requirement And Function Of Hippo Pathway Signaling In The Mammalian Gastrointestinal Tract: A Dissertation, Jennifer L. Cotton

GSBS Dissertations and Theses

In cancer, aberrant activation of developmental signaling pathways such as the Hippo Pathway has been shown to drive proliferation and invasion of cancer cells. Therefore, understanding the normal function of the Hippo Pathway during embryonic development can provide critical insight into how aberrant activity contributes to tumorigenesis. This dissertation explores the role of the Hippo Pathway members YAP and TAZ in gastrointestinal (GI) development and tumorigenesis. I use mouse genetics to systematically dissect the roles of YAP/TAZ in the endoderm-derived gastrointestinal epithelia and mesoderm-derived gastrointestinal mesenchyme during mammalian development. In the GI epithelium, I demonstrate that YAP/TAZ are ...


Depletion Of The Rna Helicase Skiv2l2 Impedes Mitotic Progression And Histone Mrna Turnover In Murine Cell Lines, Alexis Marie Onderak Oct 2016

Depletion Of The Rna Helicase Skiv2l2 Impedes Mitotic Progression And Histone Mrna Turnover In Murine Cell Lines, Alexis Marie Onderak

Dissertations (2009 -)

RNA surveillance via the nuclear exosome requires cofactors such as the helicase SKIV2L2 to process and degrade certain noncoding RNAs. This dissertation aimed to characterize the phenotype associated with RNAi knockdown of SKIV2L2 in two murine cancer cell lines: Neuro2A and P19. Skiv2l2 knockdown in Neuro2A and P19 cells induced changes in gene expression indicative of cell differentiation and reduced cellular proliferation. Analysis of the cell cycle revealed defective progression through mitosis following SKIV2L2 depletion. These results indicate that SKIV2L2 enhances mitotic progression, thereby maintaining cancer cell proliferation and preventing differentiation. Indeed, SKIV2L2 levels were found to be downregulated during ...