Molecular Biology Commons^™

Identification Of Transcriptional Mechanisms Downstream Of Nf1 Gene Defeciency In Malignant Peripheral Nerve Sheath Tumors, Daochun Sun

Wayne State University Dissertations

Malignant peripheral nerve sheath tumor (MPNST) is a type of soft tissue sarcoma that occurs in carriers of mutations in the neurofibromatosis type I gene (Nf1) as well as sporadically. Plexiform neurofibromas in NF1 patients have a significant risk of developing into MPNSTs leading to increased morbidity and mortality from this syndrome. Surgery is the primary intervention but it is not always effective due to the tendency of MPNSTs to infiltrate the surrounding tissue or grow in an inoperable location. Neurofibromin, the protein coded by the Nf1 gene, functions as a GTPase activating protein (GAP) whose mutation leads to constitutive …

Modulation Of Anti-Tumor Immune Response By Tgf-Β-Inducible Early Gene 1 (Tieg1), Andi Cani

Wayne State University Theses

Cancer immunotherapy has had limited clinical efficacy partly because regulatory T cells (Treg) suppress the immune response to tumor-associated antigens. Inducible regulatory T cells (iTreg), which are converted from naïve CD4 T cells by TGF-β, an abundant cytokine in the tumor microenvironment, may contribute to this immune suppression. Induction of Foxp3 by TGF-β is mediated by the transcription factor TIEG1 and abrogation of this protein prevents Foxp3 expression. We are testing the hypothesis that blockade of TIEG1 to prevent iTreg conversion will enhance immune response in DNA vaccination to the tumor associated antigen Her-2. Wild type and TIEG1 knockout mice …

Investigation Of A 16s Rna Central Domain Pseudoknot, Jenna Marie Jasinski-Bolak

Wayne State University Theses

X-ray crystallography of the prokaryotic 30S ribosomal subunit revealed a myriad of complex RNA-RNA, RNA-protein, and protein-protein interactions. Among these are several phylogenetically conserved RNA pseudoknots. Pseudoknots are structurally and functionally diverse RNA secondary structures. They are generally formed by two short complimentary sequences separated by many bases of single stranded regions or loops. These relatively simple folds are often yield complex structures that are key components of functionally important conformational changes in RNA structure. One such pseudoknot is located in the central domain of the 16S rRNA.

The central domain pseudoknot is formed by Watson-Crick base pairing between G570-C866 …

Mechanistic Studies Of A Novel Ppar-Gamma Mutant That Causes Lipodystrophy And Diabetes, Olga Astapova

Wayne State University Dissertations

PPAR-gamma is a nuclear receptor that plays a central role in metabolic regulation by regulating extensive gene expression networks in adipose, liver, skeletal muscle and many other tissues. Human PPAR-gamma mutations are rare and cause a monogenetic form of severe type II diabetes with metabolic syndrome, known as familiar partial lypodystrophy. The E157D PPAR-gamma mutant causes atypical lipodystrophy in a large Canadian kindred, presenting with multiple musculoskeletal, neurological and hematological abnormalities in addition to the classic lipodystrophy features of insulin-resistant diabetes, hypertension and dyslipidemia. This mutation is localized to the p-box of PPAR-gamma, a small region that interacts directly with …

Disrupting Cxcr2 Macromolecular Complex Pdz-Domain Interactions During Inflammatory Chemotaxis, Marcello Castelvetere

Wayne State University Theses

Neutrophils are the body's first responders to inflammation, being the most abundant white blood cell type in circulation and they quickly initiate an immune response through chemokine signaling. Inflammatory chemokines signal via their receptor CXCR2, which initiates an inflammatory response, recruiting leukocytes to sites of inflammation. Chemokine signaling is important for proper host protection, yet uncontrolled activity is responsible for a variety of pathological conditions: including rheumatoid arthritis, ischemia-reperfusion injury, arteriosclerosis, multiple sclerosis, psoriasis, inflammatory bowel disease, and allergic reactions.

In this report I show a CXCR2 macromolecular signaling complex exists in neutrophils, containing NHERF1 and PLCβ2. I also demonstrate …

Prevalence And Physiological Significance Of Gene Looping In Saccharomyces Cerevisiae, Banupriya Mukundan

Wayne State University Dissertations

My Ph.D. dissertation work is focused on studying the role of promoter-bound transcription initiation factors involved in gene looping. In this study we showed that the RNAP II subunit Rpb4 has a significant effect on termination of transcription. Gene looping is disrupted in the absence of Rpb4. Rpb4 shows a strong physical interaction with the Mediator subunit Srb5. Mediator subunit Srb5 crosslinked to the 5' and 3' ends of INO1 and CHA1 genes and is required for proper termination of transcription of these genes. Srb5 affected termination of transcription through its interaction with the CF1 complex. Srb5 interaction with the …

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- …

Identifying Sm22 As A Key Player In Arterial Diseases, Jianbin Shen

Wayne State University Dissertations

Background : Expression of vascular smooth muscle cell (VSMC) cytoskeleton markers including SM22 is down-regulated in arterial diseases including atherosclerosis where inflammation and osteochondrogenesis are present. However, the role of this downregulation in arterial pathogenesis is unknown. Hypothesis : Downregulation of SM22 may actively contribute to arterial pathogenesis. Methods : Five Sm22 knockout (Sm22^-/-) mice and their wild type littermates were subjected to carotid artery denudation, an artery injury model. Analyses were conducted on carotid arteries 2 weeks after injury. Primary VSMCs were isolated from mouse aortas and investigated individually at passage 2 to 4. Sm22 knockdown was …

Identification Of Cellular Functions Of Cardiolipin As Physiological Modifiers Of Barth Syndrome, Amit Shridhar Joshi

Wayne State University Dissertations

Cardiolipin (CL) is an anionic phospholipid synthesized in the mitochondrial inner membrane. Perturbation of CL metabolism leads to Barth syndrome (BTHS), a life threatening genetic disorder. I utilized genetic, biochemical and cell biological approaches in yeast to elucidate the cellular functions of CL. Understanding the functions of CL is expected to shed light on the pathology and possible treatments for BTHS.

BTHS is caused by mutations in TAZ1, which encodes a CL remodeling enzyme called tafazzin. BTHS patients exhibit a wide range of clinical presentations, indicating that physiological modifiers influence the BTHS phenotype. A targeted synthetic lethality screen was performed …

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 …

Hdm2 Small-Molecule Inhibitors For Therapeutic Intervention In B-Cell Lymphoma, Angela Sosin

Wayne State University Dissertations

Lymphomas frequently retain wild-type (wt) p53 function but overexpress HDM2, compromising p53 activity. Therefore, lymphoma is a suitable model for studying therapeutic value of disrupting HDM2-p53 association by small-molecule inhibitors (SMIs). HDM2 SMIs have been developed and are currently under various stages of preclinical and clinical investigation. This study examined various molecular mechanisms associated and biological effects of two different classes of HDM2 SMIs: the spiro-oxindoles (MI-219) and cis-imidazoline (Nutlin-3) in lymphoma cell lines and patient-derived B-lymphoma cells. Surprisingly, results revealed significant quantitative and qualitative differences between these two agents. At the molecular level, effect of Nutlin-3 was generally more …