Life Sciences Commons^™

A Tale Of Two Mechanisms: Is The P53 Modulator Coti-2 A Zinc Chaperone Instead?, Irem Simsek

Electronic Theses and Dissertations

The tumor protein p53 plays a vital role in regulating protein pathways that determine the fate of cells. Any interference with p53 function can cause disruptive cell proliferation and carcinogenesis. The p53 protein experiences a high frequency of mutation in human cancers, leading to significant research efforts to target mutant p53 and restore the normal functioning of p53. The COTI-2 small molecule, developed by COTINGA Pharmaceuticals through a computational program, has entered Phase I clinical trials. Although the mechanism of action is not fully understood, it has shown considerable promise in targeting cell lines with mutant p53. COTI-2 is believed …

Rhythms In Rna And Proliferation In Intestinal Stem Cell Organoids, Kristina Skurvidayte

Electronic Theses and Dissertations

The circadian clock is a transcription-translation feedback loop that controls our body’s daily rhythms. Previous work in our lab has shown that the circadian clock controls regeneration in the small intestinal epithelium and that the Hippo signaling pathway may serve as a link between regeneration and the circadian clock. In order to elucidate if the circadian clock directly controls the Hippo pathway as well as the Wnt pathway, both vital for intestinal homeostasis, intestinal stem cell-derived organoids, a 3D culture system that is able to recapitulate the cell biology of the intestinal epithelium in vitro, were used to examine the …

Exploring The Impact Of Src-Directed Phosphorylation On Hyvh1’S Intracellular Function, Griffin Lotze

Electronic Theses and Dissertations

Human hYVH1, also referred to as DUSP12, is a dual specificity protein tyrosine phosphatase that is highly conserved across species and has been demonstrated to be overexpressed in various cancerous states.1–4 Prior investigation of hYVH1 has implicated it in numerous cellular functions including stress response, cell survival, and cell cycle modulation.5–7 Recently, novel evidence has suggested that hYVH1 also plays a role in ribosome biogenesis, functioning in the maturation of the pre-60S ribosomal subunit by mediating its nuclear export and the ejection of Mrt4.8,9 Additionally, the well characterized tyrosine kinase Src has been suggested to trigger hYVH1 to localize into …

Biophysical Insights Into Peptide And Alcohol Perturbations On Biomimetic Membranes, Michael Hai Nguen

Electronic Theses and Dissertations

Biological membranes exist in every domain of life. Life exists due to the presence of these special structures for which we take for granted. They are composed of fatty lipids and workhorse proteins and act as the premier interface of biological processes. Due to the sheer quantity and complexity within their thin boundary, studying their actions and properties pose challenges to researchers. As a result, simplified biomembrane mimics are employed regularly. We will use several types of biomembrane mimics to understand fundamental properties of membranes. In the present thesis, we also attempt to move beyond the canonical structure-based theories upon …

Rnp Granules In Toxoplasma Gondii: Function And Formation, Scott Roscoe

Electronic Theses and Dissertations

Toxoplasma gondii is an obligate intracellular parasite capable of infecting mammals, birds, reptiles, and fish. T. gondii only undergoes sexual reproduction in a feline host. In all other organisms the parasite reproduces asexually, either as fast growing tachyzoites or slow growing bradyzoites. Bradyzoites form latent cysts inside the host cell that can lay dormant for years and convert back to tachyzoites when the host’s immune system becomes weakened. Tachyzoites rapidly replicate in the host cell, eventually causing it to lyse. While extracellular, tachyzoites repress their own translation by phosphorylating the eukaryotic initiation factor eIF2α and form microscopically visible aggregates of …

Elucidating Mechanisms For S-Nitrosoglutathione Reductase Activity And Control In Plants Using O-Aminobenzoyl-S-Nitrosoglutathione And A Novel Photo-Sensitive Probe, Leslie Ventimiglia

Electronic Theses and Dissertations

S-nitrosoglutathione reductase, (GSNOR) is widely accepted as the master regulator of stress through NO signaling and protein S-nitrosylation. GSNOR mediates stress response through the catalysis of its principal substrate S-nitrosoglutathione (GSNO). The instigation of various stressors in plants cause observable changes in plant phenotype, which are associated with changes in GSNOR activity. There are no current methods for measuring GSNOR activity directly in living plants. In this paper, a previously developed fluorogenic pseudo-substrate for human GSNOR, OAbz-GSNO, was applied to the Solanum lycopersicum plant model. OAbz-GSNO was identified as a promising novel pseudo- substrate to study changes …

Structure And Mechanics Of Biomembrane Mimics In The Presence Of Vitamin E, Mitchell Dipasquale

Electronic Theses and Dissertations

Over the course of this dissertation, the fundamental behaviours and interactions between various analogs of vitamin E and biologically-relevant membranes will be explored. These analogs include the biologically active form, α-tocopherol; the most naturally abundant form γ-tocopherol; an oxidized product, α-tocopheryl quinone; and the synthetic stabile form, vitamin E acetate.

Beginning in Chapter 1, a foundation in membrane biophysics is established from a historical progression of the field. The importance of biomembranes is argued and a deep connection is established between structure and function. Key structural features of lipid assemblies, and role of lipid composition is defined, and with the …

Regulation Of The Ribosome Biogenesis Factor Hyvh1 By Src-Mediated Phosphorylation, Ashley Anne Dadalt

Electronic Theses and Dissertations

The protein tyrosine phosphatase (PTP) superfamily is a major segment of the signal transduction landscape, responsible for regulating the biomolecular phosphorylation status of the cell. Diverse PTP subclasses exist, some of which are understudied and whose cellular functions are not yet fully elucidated. YVH1, an atypical PTP of the dual-specificity phosphatase (DUSP) subclass, is a pleiotropic enzyme with no known substrate. Human YVH1 (hYVH1) protects cells from cellular stressors, including heat shock and oxidative stress, regulates the cell cycle, disassembles stress granules, and acts as 60S ribosome biogenesis factor. Additionally, heat shock protein 70 (Hsp70) has been found to be …

Hla Blockers For Potentially Treating Rheumatoid Arthritis, Samaneh Mehri

Electronic Theses and Dissertations

Autoimmune diseases occurs when the immune system recognize self antigens in the body as foreign invaders leads to dysfunction of tissue. RA is an autoimmune disease, caused by improper recognition of self-peptides, particularly human cartilage glycoprotein and type II collagen, by specific human leukocyte antigen (HLA) receptors. Normally T-cell specific for these peptides are destroyed in the thymus before they are released, preventing autoimmunity. However, certain post-translational modifications, especially citrullination, can lead to “self-peptide” recognition by non-self T cells: in the case of RA, one HLA protein (DRB*0401), out of about 1700 possible ones, is responsible for 65% of RA …