Cell and Developmental Biology Commons^™

Transcending The Cell Fate Stereotype: Cell Penetrating Peptide Technology Helps Induce Pluripotency In Multiple Cell Types, Kelsey Clearman

Master of Science in Integrative Biology Theses

Induced pluripotent stem cells (iPSCs) are one of the most promising new technologies in the field of regenerative medicine. iPSCs can be generated directly from a patient’s own fibroblast cells then converted into any cell type, thus overcoming challenges associated with embryonic stem cells and graft-vs-host disease that result from current methods. Generation of iPSCs from fibroblasts is traditionally accomplished by ectopic expression of four key transcription factors (TFs): Oct4, Sox2, Klf4, and c-Myc also known as OSKM. These TFs have been shown to be involved in maintaining pluripotency and inhibiting embryonic stem (ES) cell differentiation. Reprogramming fibroblasts into iPSCs …

Same-Sex Marriage And The Baby Carriage: A Post-Obergefell Analysis Of Art Funding For Same-Sex Couples In The United States, Charmaine Mech

Georgia Journal of International & Comparative Law

No abstract provided.

Biosemiotics As An Argument For The Recontextualization Of Biological Discoveries: A Critical Analysis Of The Biosemiotic Model Of Marcello Barbieri., Augustus Morrissey Snyder

Senior Honors Projects, 2010-2019

The primary purpose of this project was to investigate and explain the philosophical approach of biosemiotics to understanding living systems in contrast to the current scientific paradigm. Secondary goals were to evaluate the potential merits and relevance of this approach to biology and to introduce such a topic for discussion to biologists in a formal academic setting. My method consisted of critical textual analysis supplemented by analogy and biological examples where appropriate. In general, contemporary biosemiotics argues for a teleologic recontextualization of biological discoveries in practice and education. This is accomplished in a sophisticated fashion through the application and modification …

The Beta-Catenin/Muc1.Ct Interaction In Pancreatic Cancer, Edwin Wiest

Theses & Dissertations

MUC1 is overexpressed in over 90% of pancreatic cancer cases, and its interaction with beta-catenin promotes progression of the disease. Various in vitro and in vivo methods show that beta-catenin and MUC1 interact by way of the cytoplasmic tail of MUC1 (MUC1.CT). This interaction occurs in the membrane of pancreatic cancer cells but is found to a smaller extent in the nucleus as well. Biophysical methods suggest that MUC1 interacts with beta-catenin through a sequence of amino acids in the tail of MUC1 that sit very near the transmembrane domain of MUC1. In pancreatic ductal adenocarcinoma cells, it appears that …

Mammalian Cell-Derived Vesicles For The Isolation Of Organelle Specific Transmembrane Proteins To Conduct Single Molecule Studies, Faruk H. Moonschi, Ashley M. Fox-Loe, Xu Fu, Christopher I. Richards

Chemistry Faculty Publications

Cell-derived vesicles facilitate the isolation of transmembrane proteins in their physiological membrane maintaining their structural and functional integrity. These vesicles can be generated from different cellular organelles producing, housing, or transporting the proteins. Combined with single molecule imaging, isolated organelle specific vesicles can be employed to study the trafficking and assembly of the embedded proteins. Here we present a method for organelle specific single molecule imaging via isolation of ER and plasma membrane vesicles from HEK293T cells by employing OptiPrep gradients and nitrogen cavitation. The isolation was validated through Western blotting, and the isolated vesicles were used to perform single …

The Role Of Hippo Pathway In Mitosis And Cancer, Xingcheng Chen

Theses & Dissertations

The Hippo signaling pathway has been recently elucidated as a tumor suppressor pathway controlling cell proliferation and apoptosis. The core of this pathway is a kinase cascade which contains MST1/2 (Mammalian sterile 20-like kinase 1/2), LATS1/2 (large tumor suppressor 1/2) and downstream effector named Yes-associated protein (YAP). MST1/2 transduce their kinase activity mainly through directly phosphorylating LATS1/2. Once phosphorylated and activated, LATS1/2 subsequently phosphorylate and inhibit YAP from translocating to nucleus. Current studies involving the Hippo pathway focus on determining its oncogenic role in various organs/tissues. While those studies provide important insight into the tumor suppressor properties of this pathway, …

Connexin32: Sorting, Endocytosis And Assembly, Anuttoma Ray

Theses & Dissertations

Gap junctions (GJ)s are conglomeration of several cell-cell channels at cell-to-cell contact sites involved in the direct intercellular exchange of small growth regulatory molecules. Defects in assembly of GJ-forming proteins, called connexins (Cxs), are observed in many cancers, yet the molecular basis of this defect remains unknown. Connexin32 (Cx32) is expressed by the polarized cells in epithelia. The carboxyl-terminal tail (CT) of Cx32, although not required to initiate GJ formation, orchestrates several aspects of GJ dynamics, function and growth. Our studies have discovered that the CT of Cx32 harbors a tyrosine-based [YXXØ]-type and two dileucine-based [DE]XXXL[LI]-type motifs, which govern the …

Overcoming Tcf4-Driven Bcr Signaling In Diffuse Large B-Cell Lymphoma, Keenan Hartert

Theses & Dissertations

Diffuse Large B-cell Lymphoma (DLBCL) is the most common subtype of lymphoma. Despite a cure rate of 40% with standard R-CHOP therapy, patients that refract or relapse are subject to a dismal prognosis. Cases of DLBCL can be classified by their molecular expression phenotype, with the GCB-like subtype aligning with the profile of a germinal center B-cell and the ABC-like subtype aligning to that of an activated B-cell. Aggressive disease is often characterized by high levels of B-cell Receptor (BCR) signaling. This pathway engages downstream kinases responsible for stimulating proliferation and survival that play a key role under the normal …

Functional Signature Ontology-Based Identification And Validation Of Novel Therapeutic Targets And Natural Products For The Treatment Of Cancer, Beth Neilsen

Theses & Dissertations

Multiple studies have revealed that Ras-driven tumors acquire vulnerabilities by adapting cellular mechanisms that promote uncontrolled proliferation and suppress apoptosis. Kinase Suppressor of Ras 1 (KSR1) modulates ERK activation downstream of oncogenic Ras, and knockdown of KSR1 selectively kills malignant, Ras-driven cancer cells, but does not kill immortalized, non-transformed human colon epithelial cells (HCECs). KSR1^-/- mice are fertile and phenotypically normal, but resistant to Ras-driven tumor formation suggesting KSR1 represents a vulnerability in cancer cells.

To identify additional vulnerabilities in cancer, a screening approach termed Functional Signature Ontology (FUSION) was used to screen 14,355 genes and 1,200 natural product …

Determinants Of Multi-Scale Patterning In Growth Plate Cartilage, Alek Erickson

Theses & Dissertations

ABSTRACT

Functional architectures of complex adaptive systems emerge by dynamic control over properties of individual components. During skeletal development, growth plate cartilage matches bone geometries to body plan requisites by spatiotemporally regulating chondrocyte actions. Bone growth potential is managed by the proximodistal patterning of chondrocyte populations into differentiation zones, while growth vectors are specified by the unique columnar arrangement of clonal groups. Chondrocyte organization at both tissue and cell levels is influenced by a cartilage-wide communication network that relies on zone-specific release and interpretation of paracrine signals. Despite genetic characterization of signaling interactions necessary for cartilage maturation, the regulatory mechanisms …

Elucidating The Roles Of Lunatic Fringe In Pancreatic Ductal Adenocarcinoma, Prathamesh Patil

Theses & Dissertations

Pancreatic cancer is an aggressive form of cancer that is very difficult to detect, treat resulting in a high rate of mortality. Understanding the molecular basis of pancreatic cancer and identifying new molecular targets for designing therapeutic interventions is paramount for improving outcomes in this disease. Notch signaling is a vital developmental signaling pathway that has been implicated to play both oncogenic and tumor suppressive roles in pancreatic cancer. Previous studies from other groups have shown that O-linked glycosylation of Notch signaling plays a key role in the regulation of Notch signaling. Lunatic fringe (Lfng) is one of the glycosyltransferases …

Functional Role Of Protein Kinase C Alpha In Endometrial Carcinogenesis, Alice Hsu

Theses & Dissertations

Protein kinase Cα (PKCα) is a member of the PKC family of serine/threonine kinases that regulate many fundamental cellular processes, including cell proliferation, differentiation, survival and transformation. The impact of PKCα on tumorigenesis, and whether it acts as an oncogene or tumor suppressor, has been debated over the years. The overall goal of this study was to establish the functional role of PKCα in endometrial carcinogenesis. Results from this study broaden our knowledge of PKCα signaling and add to our understanding of its role in tumor development.

As understanding of the role of PKCα signaling in the uterus is limited, …

Modeling And Analyzing An Optogenetic System For Photoactivatable Protein Dissociation, Anvin Thomas, James Schaff

Honors Scholar Theses

Computational modeling of cell-cell interactions can grant clues and can answer questions about an experiment, especially for observations about binding interactions and kinetics. This approach was used to investigate an interaction between a light-oxygen-voltage (LOV) domain and an engineered protein called Zdark (Zdk). The LOV domain is membrane-bound while Zdk is cytosolic. The LOV domain and Zdk bind strongly in dark (K_d 26.2 nM), and weakly upon exposure to blue light (K_d > 4 μM). Total internal reflection fluorescence (TIRF) images are acquired of Zdk, the fluorescent species bound to a mCherry tag, and the loss of fluorescence is …

Investigating Interspecific And Intraspecific Variation In Lung Development In Amphibians, Courtney Neumeyer

Masters Theses, 2010-2019

Amphibians occupy an intermediate phylogenetic position between fish and tetrapods, making amphibians an essential model for understanding the evolution of air breathing organs in vertebrates. Amphibians have a uniquely biphasic life style allowing them to occupy aquatic and terrestrial habitats and to use multiple organs for gas exchange at different stages of life. This initial independence from lung breathing means that amphibians are developing their lungs while they are using them, which opens up the possibility that their rate of lung development is controlled in part by their breathing behavior. As such, amphibians provide a starting point for examining the …

Characterizing Epigenetic Regulation In The Developing Chicken Retina, Bejan Abbas Rasoul

Masters Theses, 2010-2019

The retina, the sensory neuronal tissue within the eye, is composed of three layers of neuronal cells connected by two synaptic layers lining the inside of the anterior portion of the eye. Multipotent retinal precursor cells are genetically homogeneous and differentiate into mature retinal neurons due to differential gene expression. Differences in gene expression have been correlated with epigenetic modifications such as DNA methylation. DNA methylation of upstream regulatory elements is associated with transcriptional silencing of gene expression. Years of research in retinal development has identified the numerous genes expressed during the main steps of retinal development, however, it is …

An Examination Of Preimplantation Embryos And Endometrium Developed During Induced Aluteal Cycles In The Mare, Chelsey Audra Leisinger

LSU Doctoral Dissertations

Changes to the embryonic environment that occur within the first few days of development can have significant effects on subsequent fetal development. The following studies investigate the effects of progesterone-deprivation during the early preimplantation period in the mare. The first study described embryo morphology (diameter, stage, and quality grade) collected from mares with induced aluteal cycles. The second study evaluated the effect of induced aluteal cycles on the future fertility of embryo collections as a potential method for cycle manipulation of embryo donor mares. The third study characterized embryonic and endometrial transcript expression of progesterone-mediated transcripts as well as those …

Pyruvate Kinase Isoform M2 Influences Autophagy And Related Processes In Hepatocellular Carcinoma Cells, Matthew Lin

University Scholar Projects

Hepatocellular carcinoma (HCC) is the most common form of liver cancer that affects ~14 million people in the world. Like all cancers, HCC is a disease that arises from unstinted cellular growth initiated by genetic alterations, metabolic changes, and dysregulation in key cellular pathways. Of interest is the relationship between metabolism and cell proliferation/degradation for therapeutic targeting. Pyruvate kinase M2 is a dimeric, glycolytically inactive isoform of the final enzyme involved in glycolysis, that is often upregulated in cancerous tissue. It is thought that the enzymatic function of PKM2 outside of glycolysis contributes to the biosynthesis of anabolic intermediates used …

Investigation Of P-Glycoprotein (Pgp) Induction By Pgp Substrates To Induce Paclitaxel Resistance In Ovarian Cancer Cells, Ryker Penn

Theses & Dissertations

The purpose of this study was to investigate the development of chemotherapeutic resistance to paclitaxel in ovarian cancer cells after treatment with drugs that are substrates for P-glycoprotein (PGP). A core concept of this experiment was to identify if PGP substrate drugs could also act as PGP inducers after prolonged treatment in SKOV-3 ovarian cancer cells. In order to test this, SKOV-3 cells were exposed to either fexofenadine, a PGP substrate used as an antihistamine, or the chemotherapeutic drug vinblastine. After 42 days of drug treatment, ABCB1 gene expression was measured by qRT-PCR. Analysis of ABCB1 expression in treated cells …

Functional Studies Of The E. Coli Proc And A Putative Ortholog Mrub_1345, Maureen Azar, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

This project is part of the Meiothermus ruber genome analysis project, which uses the bioinformatics tools associated with the Guiding Education through Novel Investigation –Annotation Collaboration Toolkit (GENI-ACT) to predict gene function. We investigated the biological function of Escherichia coli and Meiothermus ruber proC genes using the complementation assay. In this research project, mutants of varying severity to the functional state of the protein were developed. The results showed that two or more amino acid deletions reduced or eliminated ProC function. Amino acid substitutions, on the other hand, were not severe enough to impact ProC function. Double and triple mutants …

Effect Of Silk-Based Hydrogel Topography On Intestinal Epithelial Cell Morphology And Wound Healing In Vitro, Marisa E. Boch

University Scholar Projects

Recent advances in the field of biomaterials have suggested that cells cultured on substrates resembling the native tissue mechanical properties, matrix and growth factor composition, and topography can adopt phenotypes that more closely resemble the in vivo tissue compared to cells cultured on non-mimetic constructs. Understanding the effect of culture substrate on in vitro tissue formation is important for bioengineering applications that include mechanistic studies of healthy tissue function and development of disease models. In this work, Caco-2 adenocarcinoma cells were seeded on flat and crypt-like topographies of 3D-printed cytocompatible hydrogels derived from silk fibroin protein. Silk hydrogels were selected …