Life Sciences Commons^™

Analyzing The Regulation, Stability And Functional Differences Between Sin3 Isoforms In Drosophila, Ashlesha Chaubal

Wayne State University Dissertations

SIN3 is a master transcriptional regulator, conserved from yeast to mammals, that acts as a scaffold protein for a histone modifying complex. In Drosophila, a single Sin3A gene is alternatively spliced to produce distinct SIN3 isoforms; SIN3 220, SIN3 190 and SIN3 187, that differ only at their C-terminus. These isoforms are differentially expressed during development. We have shown that there is an interplay between the predominant isoforms of SIN3, SIN3 220 and SIN3 187, that possibly regulates the overall level of SIN3 in the cell. Exogenous expression of SIN3 187 reduces the level of transcript and accelerates the proteasomal …

Identifying The Function Of The Calpain Small Subunit In The Mechanics Of Cell Migration, Bingqing Hao

Wayne State University Dissertations

Cell migration plays a vital role in many physiological events including: morphogenesis, wound healing, and immune response. Dysfunctional cell migration results in multiple disease states including chronic inflammation, vascular disease, and tumor metastasis, to name a few. Progress in understanding the mechanism of cell migration had been slow until the turn of the century when rapid technological advances in microscopy and omics burst to the forefront. These advances led to the realization that physical factors (dimensions, fluid shear stress, hydrostatic pressure, compression stress, environmental stiffness, and topography) have profound effects on cell migration. This study of cell mechanics has expanded …

Understanding The Mechanism Of Oxidative Stress Generation By Oxidized Dopamine Metabolites: Implications In Parkinson's Disease, Nihar Mehta

Wayne State University Dissertations

Oxidation of dopamine to toxic metabolites is considered to be one of the prime factors involved in the death of dopaminergic neurons in Parkinson’s disease. Some dopamine oxidation products have the capability to redox cycle in the presence of molecular oxygen, further contributing to oxidative stress. Therefore, our aim here was to study the redox cycling of dopamine oxidized metabolites and elucidate the underlying mechanism by which they cause oxidative stress.

Redox reactions involve transfer of one or more electrons between two compounds

resulting in either oxidation or reduction. In redox cycling, a compound undergoes

alternate oxidation and reduction, transferring …

Functional Analysis Of Sin3 Isoforms In Drosophila, Nirmalya Saha

Wayne State University Dissertations

he multisubunit SIN3 complex is a global transcriptional regulator. In Drosophila, a single Sin3A gene encodes different isoforms of SIN3, of which SIN3 187 and SIN3 220 are the major isoforms. Previous studies have demonstrated functional non-redundancy of SIN3 isoforms. The role of SIN3 isoforms in regulating distinct biological processes, however, is not well characterized. In addition, how the components of the SIN3 complex modulate the gene regulatory activity of the complex is not well understood. In this study, I identified the biological processes regulated by the SIN3 isoforms. Additionally, I explored how Caf1-55 impacts the gene regulatory activity of …

Pet Imaging Of Early Therapeutic Response In Solid Tumors, Stephanie J. Blocker

Wayne State University Dissertations

An important pillar of precision medicine for oncology is the ability to identify patients who respond to treatment early into their therapy. Positron emission tomography (PET) allows physicians and researchers to measure changes in tumor behavior prior to noticeable differences in morphology.

Objective: Determine the utility of multiple tracers for PET in assessing early changes in tumor activity that result from treatment.

Methods: Two tracers for PET were studied. 64Cu-labeled liposomes were used to assess changes in liposome delivery two solid colon tumors early into treatment with bevacizumab (Bev). 18F-FMAU thymidine analog (1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)thymine), was utilized to detect early response to …

Novel Functions Of Cardiolipin Remodeling In Saccharomyces Cerevisiae And Mammalian Cells: Implications For Barth Syndrome, Wenjia Lou

Wayne State University Dissertations

Cardiolipin (CL) is a unique phospholipid that is primarily localized within the inner mitochondrial membrane. Newly synthesized CL undergoes acyl remodeling to produce CL species enriched with unsaturated acyl groups. The tafazzin gene (TAZ) encodes a transacylase that remodels CL. Deficiencies in CL remodeling cause Barth syndrome (BTHS), an X-linked genetic disorder resulting from TAZ mutations that lead to reduced total CL content and an accumulation of monolysocardiolipin (MLCL), an intermediate of the CL remodeling pathway. However, which of these biochemical outcomes contributes to the physiological defects is not fully understood.

Deletion of yeast CL phospholipase rescues the taz1growth phenotype. …

Determination Of The Direct Protein-Protein Interactions In The Drosophila Sin3a Complex, Ian Moore

Wayne State University Theses

The proteins that comprise the Drosophila SIN3 220 and SIN3 187 complexes are currently known. Limited information with regard to interacting complex member proteins has been described. Much of these data are results of high-throughput investigations, and there have been no studies done to reconstitute all direct interactions within the complex. The unique C-terminal region of the SIN3 220 isoform was used to test for interactions with other complex proteins using the bacterial expression system. Additionally, the region of Caf1-55 necessary for interaction with SIN3 in vivo was identified using a truncation mutant. The results of this work identified novel …

Synaptotagmin C2b Ca2+-Binding Loops Impose Distinct Exocytosis Phenotypes, Michael W. Schmidtke

Wayne State University Theses

Regulated exocytosis from chromaffin cells in the adrenal medulla plays a critical role in maintaining organismal homeostasis. In the absence of stress, these cells release physiologically relevant substances into the blood stream only in limited quantities, whereas stressful conditions result in a rapid deluge of signaling molecules used, for example, to increase heart rate and pain tolerance. Although the cellular mechanisms governing the switch from low-level to stress-induced secretion are not well understood, recent evidence has implicated the exocytotic Ca2+-sensing protein Synaptotagmin (Syt) in this role.

Two isoforms of Syt are expressed in chromaffin cells (Syt-1 and Syt-7), and each …

Identification Of Oxygen Optima For Mouse Trophoblast Stem Cells And Human Embryos And The Stress Responses Upon Departing Optima, Yu Yang

Wayne State University Dissertations

Low level of oxygen (O2) occurs physiologically during in vivo embryo development. As developing embryos moving from fallopian tube to uterus, oxygen level gradually decreases to ≤ 5% at the time of blastocyst implantation. Blastocysts are made of two major cell populations, trophoblast cells and inner cell mass, from which trophoblast stem cells (TSCs) and embryonic stem cells (ESCs) are derived respectively. TSCs serve as placental stem cells that later on proliferate and differentiate into placenta. Previous study has shown that 2% O2 is the optimal O2 level for mTSC in vitro growth and potency maintenance, which agrees with their …

Navigating Human Cytomegalovirus (Hcmv) Envelopment And Egress, William Longeway Close

Wayne State University Dissertations

Human cytomegalovirus (HCMV) is a ubiquitous viral pathogen. In individuals with fully functioning and mature immune systems, HCMV is associated with mild symptoms prior to establishing latency. In individuals with naïve or compromised immune systems, HCMV is capable of causing severe organ damage. HCMV is the leading infectious cause of congenital birth defects and a major non-genetic cause of hearing loss. Unfortunately, antiviral treatment options lack diversity due to limited knowledge of virion replication. If HCMV replication were better understood, new antiviral treatments could be developed.

In this work, we describe the development and implementation of new tools to study …

Targeting Host Defense: The Dynamic Nd10 Interaction And The Differential Substrate Recognition Of Hsv-1 Icp0, Yi Zheng

Wayne State University Dissertations

ICP0 is one of the immediate early viral proteins and essential for HSV-1 replication in low MOI infection. ICP0 is involved in manipulating various cellular pathways and attenuating their inhibitory functions on viral replication through either protein-protein interaction or using its E3 ligase activity to degrade restrictive factors. Upon infection, HSV-1 viral DNA is injected into the nucleus and found to be closely associated with ND10. ND10 association with viral DNA causes the repression of viral gene expression, which is inactivated by ICP0. HSV-1 employs ICP0 to target key ND10 components PML and Sp100 for proteasomal degradation, leading to the …