Molecular Biology Commons^™

Characterization And Identification Of Novel Regulators Of The Synthesis Of Phospholipids, Cunqi Ye

Wayne State University Dissertations

Phospholipids are the most abundant lipids in cell membranes. The synthesis of phospholipids is crucial for cellular membrane biogenesis and nearly all aspects of cellular processes. Understanding the regulation of synthesis of phospholipids is beneficial to our fundamental knowledge of cell biology as well as human health.

Regulation of the synthesis of phospholipids is intensively studied in the yeast S. cerevisiae. Most notably, the synthesis of phospholipids is coordinated with the synthesis of inositol, a precursor of inositol-containing lipids, by controlling expression of the genes encoding phospholipid biosynthetic enzymes. In addition to this well-characterized regulatory circuit controlled by the …

Rates And Modes Of Sequence Evolution In Various Lineages Within Chenopodiaceae, James Andrew Naeger

Wayne State University Theses

Sexual dimorphism in domesticated spinach, Spinacia oleracea, is thought to be determined by differential expression of floral organ identity genes. We examined the floral organ morphologies of seven species in the Chenopodiaceae, including two wild species of spinach, in order to gain insight into the evolution of floral reproductive strategy in this clade. The species within the Anserineae demonstrate extensive evolution in floral morphology and reproductive strategy, and Spinacia is unique for having been domesticated rather recently and for being dioecious. We found C. album to be hermaphroditic, C. foliosum and M. nuttalliana to be gynomonoecious, while C. bonus-henricus …

In Vitro Characterization Of Serine 47 Phosphorylated Cytochrome C, Ashwathy Mary Varughese

Wayne State University Theses

Cytochrome c is a 12.4kDa ubiquitously expressed protein known to be involved in many physiological processes of the cell such as respiration and apoptosis. The goal of our lab is to increase our knowledge of the regulation of cytochrome c in these opposite activities, and our working model posits that cytochrome c is decisively regulated by phosphorylation. When phosphorylated, cytochrome c leads to an "optimal" functioning in the electron transport chain by lowering electron flux, preventing harmful high mitochondrial membrane potentials and thus ROS production under healthy conditions. However, under cellular stress cytochrome c might be dephosphorylated favoring high mitochondrial …

The Nh2-Hypervariable Region Modulates The Binding Affinity Of Troponin T For Tropomyosin, Chinthaka Kaushalya Amarasinghe

Wayne State University Theses

The troponin complex plays a central role in the allosteric function of sarcomeric thin filaments by enacting conformational changes during the Ca2+-regulated contraction and relaxation of striated muscle. The troponin subunit T (TnT) has two binding sites for tropomyosin (Tm) and is responsible for anchoring the troponin complex to the thin filament. Although the C-terminal and middle regions of the TnT polypeptide chain are highly conserved among the three muscle type isoforms, the hypervariable N-terminal region has evolutionarily diverged significantly among isoforms. Previous studies have shown that the N-terminal variable region fine-tunes Ca2+ regulation of muscle contractility via modulation of …

Tmprss2-Erg Regulation Of Androgen Biosynthetic Enzyme Expression, Dht Synthesis, And Androgen Receptor Activation In Prostate Cancer, Katelyn Ann Powell

Wayne State University Dissertations

Intratumoral androgen synthesis in prostate cancer (PCa) contributes to the development of castration-resistant prostate cancer (CRPC). Several enzymes responsible for androgen biosynthesis have been shown to be overexpressed in CRPC, thus, contributing to CRPC in a castrated environment. Although intratumoral androgen synthesis is thought to contribute to the development and progression of CRPC, currently little is known regarding the regulation of androgen biosynthetic enzyme gene expression in PCa. The TMPRSS2-ERG transcription factor has been shown to be present in primary PCa tumors as well as CRPC tumors. The hypothesis was investigated that TMPRSS2-ERG fusions regulate androgen biosynthetic enzyme (ABE) gene …

Molecular Studies On The Anti-Tumor Effects Of Metal-Based Complexes: Involvement Of The Ubiquitin-Proteasome And Apoptotic Pathways, Sara M. Schmitt

Wayne State University Dissertations

The ubiquitin-proteasome pathway is crucial to normal cellular function, and as such, has been extensively investigated as a potential target for cancer therapeutics. Many compounds have been tested for their proteasome inhibitory ability, including various small peptide aldehydes, and, following the success of cisplatin, several metal-containing complexes. The efficacy of these compounds in preclinical studies ultimately resulted in the development and approval of the first-in-class proteasome inhibitor bortezomib, the use of which, unfortunately, has been hindered by toxicity and resistance. These limitations have led to a massive push toward designing and developing new, less toxic proteasome inhibitors for clinical use. …

Proximate And Evolutionary Insights Into The Epigenetics Of Posttraumatic Stress Disorder, Levent Sipahi

Wayne State University Dissertations

Posttraumatic stress disorder (PTSD) is an important medical and social condition. Although the vast majority of individuals are exposed to traumatic events within their lifetime, a minority subsequently develop diagnosable PTSD. What underlies differential risk and resiliency in the face of trauma is an ongoing research and clinical question with implications for prevention and treatment. Recent work has revealed a putative role of epigenetic variation and modification - most notably DNA methylation - in the etiology of PTSD. That DNA methylation is stable, yet modifiable in response to lived experiences, makes it a strong candidate to mechanistically explain the ontogeny …

Linking Molecular, Electrical And Anatomical Properties Of Human Epileptic Brain, Shruti Bagla

Wayne State University Dissertations

Epilepsy is a common neurological disorder of recurrent unprovoked seizures. It affects almost 1% of the world population. Although there is a wide range of anti-epileptic drugs (AEDs) available, they only treat the seizure symptoms and do not cure the disease itself. The poor role of AEDs can be attributed to the lack of knowledge of exact mechanisms and networks that produce epileptic activities in the neocortex. At present, the best cure for epilepsy is surgical removal of electrically localized epileptic brain tissue. Surgically removed brain tissue presents an excellent opportunity to discover the molecular and cellular basis of human …

Regulation Of Inositol Biosynthesis And Cellular Consequences Of Inositol Depletion: Implications For The Mechanism Of Action Of Valproate, Rania M. Deranieh

Wayne State University Dissertations

Inositol is a six-carbon cyclitol that is ubiquitous in biological systems. It is a precursor for the synthesis of numerous biologically important compounds, including inositol phosphates and phosphoinositides that are essential for cell function and viability. Inositol compounds play a role in membrane formation, gene regulation, signaling, regulation of ion channels, and membrane trafficking. Furthermore, inositol regulates hundreds of genes, including those involved in the biosynthesis of inositol and phospholipids. While transcriptional regulation of inositol biosynthesis has been extensively studied and well characterized, regulation of inositol biosynthesis at the enzymatic level has not been addressed. The current study shows that …

Sex And Heterochromatin: An Investigation Of Sexual Dimorphism In Drosophila Melanogaster, Manasi S. Apte

Wayne State University Dissertations

Over 30% of Drosophila genome is assembled into heterochromatin. Heterochromatin is relatively gene poor, transcriptionally less active and remains condensed during interphase. Previous studies established that roX RNA and some of the Male Specific Lethal (MSL) proteins, all components of the dosage compensation complex, are required for full expression of autosomal heterochromatic genes in male flies but not in females. This was surprising since heterochromatin is generally not thought to be sexually dimorphic. The genetic basis for the regulation of sex-specific heterochromatin was completely unknown.

To determine if roX RNAs localize directly at the heterochromatic regions that they regulate, I …

The Drosophila Interactions Database: Integrating The Interactome And Transcriptome, Thilakam Murali

Wayne State University Dissertations

In this thesis I describe the integration of heterogeneous interaction data for Drosophila into DroID, the Drosophilainteractions database, making it a one-stop public resource for interaction data. I have also made it possible to filter the interaction data using gene expression data to generate context-relevant networks making DroID a one-of-a kind resource for biologists. In the two years since the upgraded DroID has been available, several studies have used the heterogeneous interaction data in DroID to advance our understanding of Drosophila biology thus validating the need for such a resource for biologists. In addition to this, I have identified …

Roles Of Neuregulin1 In Neuromuscular Junction Development, Jiajing Wang

Wayne State University Dissertations

Neuromuscular junction (NMJ) development is a multistep process mediated by coordinated interactions between nerve terminals, target muscles, and peri-synaptic glial cells, and thus requires reciprocal signals derived from every cell type. Neuregulin1s (NRG1s) are a family of predominantly neuronal growth and differentiation factors that are important for many aspects of nervous system development. In this thesis, both the effects of NRG1 on NMJ development and reciprocal effects of neurotrophic factors on NRG1 expression were studied as a means to define the complex regulatory communication at the NMJ. Using the chicken embryo as a model, methods were developed to study the …

The Role Of Cardiolipin In Iron Homeostasis And Glutathione Metabolism, Vinay A. Patil

Wayne State University Dissertations

Cardiolipin (CL) is the signature phospholipid of mitochondrial membranes, where it is synthesized locally and plays a critical role in mitochondrial bioenergetic functions. Inside the mitochondria, CL is a critical target of mitochondrial generated reactive oxygen species (ROS) and regulates signaling events related to apoptosis and aging. CL deficiency causes perturbation of signaling pathways outside the mitochondria, including the PKC-Slt2 cell integrity pathway and the high osmolarity glycerol (HOG) pathway, and is a key player in the cross-talk between the mitochondria and the vacuole. The importance of CL in human health is underscored by the observation that perturbation of CL …

Polymeric Nanocarriers And Their Oral Inhalation Formulations For The Regional Delivery Of Nucleic Acids To The Lungs, Denise Santos Conti

Wayne State University Dissertations

Gene therapy has attracted attention in the fields of medicine, pharmacy, and bionanotechnology due to the potential for treating a large number of medically relevant diseases. Oral inhalation (OI) is a promising route for the administration of therapeutics, including small molecules and biomacromolecules, such as nucleotides, peptides, and proteins, to (locally) and through (systemically) the lungs. The use of OI is especially attractive for the delivery of nucleic acids as it provides a direct and non-invasive route for targeting the lungs. Pressurized metered-dose inhalers (pMDIs), are the most commonly used OI in treatment of lung diseases and are thus promising …

Investigating The Metal Binding Affinity Of Bacterial Zinc Transporters: Zupt And Truncated Znta (Znta-Pina), Fei Nie

Wayne State University Theses

Zinc is essential trace elements for all living organisms and serves as cofactor and structural cofactors for more than 300 enzymes. ZupT is one of the members of ZIP super family of transporter proteins, which were identified as iron and zinc transporter in Eukaryotes at first. However, recent evidence showed that some of members can also transport other metal ions, such as manganese or cadmium, and ZIP proteins also exist in bacteria. ZupT is responsible for zinc uptake in E. coli; however, its full metal selectivity is not yet characterized. In addition, the mechanism of transport is also unknown. Therefore, …

The Mononuclear Metal Center Of Type-I Dihydroorotase From Aquifex Aeolicus, Brian Fp Edwards, Roshini Fernando, Philip D. Martin, Edward Grimley, Melissa Cordes, Asmita Vaishnav, Joseph S. Brunzelle, Hedeel Evans, David R. Evans

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Dihydroorotase (DHO) is a zinc metalloenzyme, although the number of active site zinc ions has been controversial. E. coli DHO was initially thought to have a mononuclear metal center, but the subsequent X-ray structure clearly showed two zinc ions, α and β, at the catalytic site. Aquifex aeolicus DHO, is a dodecamer comprised of six DHO and six aspartate transcarbamoylase (ATC) subunits. The isolated DHO monomer, which lacks catalytic activity, has an intact α-site and conserved β-site ligands, but the geometry of the second metal binding site is completely disrupted. However, the putative β-site is restored when the …

Disulfide By Design 2.0: A Web-Based Tool For Disulfide Engineering In Proteins, Douglas B. Craig, Alan A. Dombkowski

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Disulfide engineering is an important biotechnological tool that has advanced a wide range of research. The introduction of novel disulfide bonds into proteins has been used extensively to improve protein stability, modify functional characteristics, and to assist in the study of protein dynamics. Successful use of this technology is greatly enhanced by software that can predict pairs of residues that will likely form a disulfide bond if mutated to cysteines.

Results

We had previously developed and distributed software for this purpose: Disulfide by Design (DbD). The original DbD program has been widely used; however, it has a number …

Role Of Phosphoylation Of The Mycobacterium Tuberculosis Proteasome In Oxidative Stress Response And Regulation Of Homoserine Kinase (Thrb) In Corynebacterium Glutamicum, Heather Baun

Wayne State University Theses

Part 1:

One-third of the world's population is infected with the latent form of Mycobacterium tuberculosis. M. tuberculosis must be able to control this latent even in response to nitrosative and oxidative stress conferred by the host. It is not well known how M. tuberculosis controls this state.

One possibility for this control is through its eleven eukaryotic-like serine/threonine protein kinases. Our lab has focused research on two eukaryotic-like ser/thr protein kinases, PknA and PknB. It has been found that PknA expression may affect the stability or the assembly of the proteasome complex, which is essential for M. tuberculosis to …

Investigation Of Bacterial Rna-Directed Dna Methylation Via Dcm And Hfq, Dandan Li

Wayne State University Theses

Bacterial small RNAs and the RNA chaperone Hfq play crucial roles in post-transcriptional gene regulation, often as parts of stress-response pathways, but little is known about their roles in regulation of gene transcription. A recent report showed that changes in methylation patterns caused by DNA cytosine methyltransferase (Dcm) were linked to gene regulation occurring during the transition to stationary phase. Here, we show that Dcm involves in the stress responses under nutrient starvation and cold stress. Dcm and Hfq together mediate gene expression under cold stress. Hfq promotes Dcm-catalyzed cytosine methylation at specific sites near the rpoS promoter, which is …

Effect Of Folate Deficiency And Aging On Mtor Signaling Network In The Liver Of Dna Polymerase B Haploinsufficient Mice, Amanda Lynn Arrabi

Wayne State University Theses

EFFECT OF FOLATE DEFICIENCY AND AGING ON mTOR SIGNALING NETWORK IN THE LIVER OF DNA POLYMERASE B HAPLOINSUFFICIENT MICE

by

AMANDA ARRABI

August 2013

Advisor: Dr. Ahmad R. Heydari

Major: Nutrition and Food Science

Degree: Masters of Science

The interaction between the dietary nutrients and the human genome causes some alterations in the molecular pathways that could significantly impact the development of cancer. The main approach to such concerns is to closely observe how the diet modifies the gene expressions that control several cellular processes in the human body. Folate deficiency (FD) has established an important role in modulating the …

Cysteine Desulfurase And Isd11: A Drosophila Model, Rahul Ravindran Nair

Wayne State University Theses

ABSTRACT

Cysteine desulfurase and Isd11: A Drosophila model

Iron-sulfur clusters are cofactors with evolutionary origins that date back to the pre-biotic world. Ever since life originated, these cofactors have intermingled with proteins to play vital roles in sustaining life. My research focuses on one such protein, the cysteine desulfurase (Nfs) that has the PLP cofactor incorporated in its active site and avails of the catalytic property of PLP to provide sulphur for Iron-sulfur cluster biogenesis and assembly in a cell. Interestingly, in a eukaryotic cell, despite the versatility of PLP, cysteine desulfurase's role as a "sulphur-extractor" is incomplete without another …

Studies Of Regulated Exocytosis From Neuroendocrine Cells, Madhurima Das

Wayne State University Theses

In this thesis we study cargo release and fusion pore dilation during calcium triggered exocytosis and the co-localization of calcium sensing proteins essential for exocytosis, in neuroendocrine cells.

Pancreatic beta cells secrete several hormones, the most studied one being insulin. C-peptide is a protein which is co-stored with and secreted from the same vesicles as insulin. It is found in the soluble phase unlike insulin, which is found in the dense core. The pancreatic beta cells also secrete the Chromogranin B (CgB) which is mostly found in the dense cores of secretory vesicles. In chapter 1, we found that CgB, …

Optimization Of Labeling Techniques; Determination Of Best Parameter For Olfactory Mucosal Progenitor Cell Delivery And Study Of Effects Of Methylene Blue And Polyethylene Glycol In An Animal Model Of Spinal Cord Injury, Kiran Kumar Rokkappanavar

Wayne State University Theses

In the United States, the incidence of TSCI is about 40 per million persons per year, with approximately 250,000 living survivors of TSCI in the United States in July 2005. A number of human clinical trials (85) are ongoing using stem cells to evaluate the methods to reduce the injury following TBI. Among the stem cells, olfactory mucosal progenitor cells have several advantages with respect to ease of obtaining, fate of cells, etc. Our study was intended to optimize the labeling technique and to determine the best parameter to deliver the stem cells to the site of injury. We found …

Characterizing Cyclin J By Identifying Conserved Protein-Protein Interactions, Phillip Jacob Selman

Wayne State University Theses

Cyclins are proteins that bind to Cyclin-dependent kinases, or Cdks, through a conserved domain called the Cyclin Box. Many Cyclins regulate the cell cycle. A few Cyclins impact cellular processes outside of the cell cycle. Also, a few Cyclins have poorly understood functions.

Cyclin J is a member of the Cyclin superfamily of proteins. Cyclin J is conserved among all metazoans, but is presently not well understood. All the research done on Cyclin J has been done in Drosophila.

Its mRNA is present in the early embryo, then disappears, only to reappear in adult females. When probing protein extracts with …

Investigation Of X Chromosome Recognition: The Role Of Small Rna In Drosophila Dosage Compensation, Debashish Unnikrishnan Menon

Wayne State University Dissertations

In humans and flies, females have two X chromosomes but males have one X chromosome and one Y chromosome. This leads to a fatal imbalance in X-linked gene expression in one sex. In mammals and in the fruit fly Drosophila, modulation of X chromosome expression is critical for survival. This process is termed dosage compensation. Flies increase expression from the male X chromosome two-fold. This is achieved by the Male Specific Lethal (MSL) complex, which consists of two large, non-coding RNA on the X transcripts (roX1 and roX2) and five proteins. The roX RNAs have a critical …

Acidic Pericellular Ph: Effects On Proteolysis And Gene Expression As Determined In 3d Models Of Breast Carcinoma, Jennifer M. Rothberg

Wayne State University Dissertations

Among the non-cellular microenvironmental factors that contribute to malignancy of solid tumors is an acidic peritumoral pH. The first objective was to determine if an acidic extracellular pH observed in vivo (i.e., pHe 6.8) affects the activity of proteases, such as cathepsin B, that contribute to degradation of collagen IV by tumor cells when grown in biologically relevant three-dimensional cultures. At pHe 6.8 there were increases in pericellular active cysteine cathepsins and in degradation of DQ-collagen IV, which was partially blocked by a cathepsin B inhibitor. Imaging probes for active cysteine cathepsins localized to tumors in vivo. The amount of …

The Transcriptional Regulation Of Flagellin-Induced Innate Protection Of The Cornea: Role Of Irf1 And Atf3, Gi Sang Yoon

Wayne State University Dissertations

Pre-exposure of the cornea to TLR5 ligand flagellin induces profound mucosal innate protection against infections by reprogramming gene expression. This study explored the flagellin-induced modifications of transcription factor expression and function, specifically of IRF1 and ATF3 in corneal epithelial cells to elucidate the transcriptional mechanisms underlying the protective function of flagellin on the cornea.

Initially we used Superarray to screen for transcription factors and identified Interferon Regulatory Factor (IRF) 1 and Activating Transcription Factor (ATF) 3 as the most drastically affected genes by flagellin pretreatment in P. aeruginosa challenged human corneal epithelial cells (CEC). However, flagellin pretreatment had opposite effects …

Biochemical, Structural, And Drug Design Studies Of Multi-Drug Resistant Hiv-1 Therapeutic Targets, Tamaria Grace Dewdney

Wayne State University Dissertations

Protein point mutations acquired as a mechanism of survival against therapeutics cause structural changes that effect protein function and inhibitor binding. This work investigates the structural mechanisms that lead to multi-drug resistance to HIV-1 protease and integrase inhibitors.

Proper proteolytic processing of the HIV-1 Gag/Pol polyprotein is required for HIV infection and viral replication. This feature has made HIV-1 protease an attractive target for antiretroviral drug design for the treatment of HIV-1 infected patients, thus the development of drug resistance has arisen as a major therapeutic and drug design challenge. To understand the molecular mechanisms leading to drug resistance we …

Genetic And Biochemical Studies Of Human Apobec Family Of Proteins, Priyanga Wijesinghe

Wayne State University Dissertations

The AID/APOBEC family of proteins in higher vertebrates converts cytosines in DNA or RNA into uracil. These proteins have essential roles in either innate immunity or adaptive immunity. Recently, AID has also been implicated in DNA demethylation in the context of early embryogenesis in mammals. This is partly based on the reported ability of AID to deaminate 5-methyl cytosine to thymine (5mC to T). I reexamined this proposed new role of AID (5mC deamination) with two members of the APOBEC family in a novel Escherichia coli based genetic system. My results confirmed that while all three enzymes are strong cytosine …

In Vivo Display: A Selection And Its Derivatives For Antimicrobial Peptide Lead Identification, Wesley David Colangelo

Wayne State University Dissertations

The rise of antibiotic resistance necessitates new approaches for the isolation of new antimicrobials with novel inhibitory mechanisms, bypassing the development of rapid resistance by modification of pre-existing resistance mechanisms. In response, we have developed a series of systems for the rapid isolation and identification of peptides that inhibit the growth of Escherichia coli and other bacteria, termed in vivo display (IVD).

IVD harnesses the cellular processes of E. coli for the expression of a library of random peptides at the terminus of a display protein. A library of 12-amino acid random peptide sequences was added to either the C- …