Life Sciences Commons^™

The Role Of Mitochondria In The Radiation-Induced Bystander Effect In Human Lymphoblastoid Cells, Sountharia Rajendran

Wayne State University Theses

This work evaluated the radiation-induced bystander effect in mitochondrial mutant cells and in normal cells treated with mitochondrial inhibitors. Although much research has been performed on the bystander effect, the underlying molecular mechanisms remain largely unknown. Cells without intact mitochondrial DNA have been shown to lack the bystander effect, which is an energy-dependent process. Based on these findings, cells harboring mutations in the mitochondrial genes responsible for ATP synthesis, and normal cells treated with mitochondrial inhibitors, were hypothesized to show a decreased bystander effect when compared to normal cells that were not treated with the mitochondrial inhibitors.

Radiation-induced bystander effects …

The Drosophila Homolog Of The Mammalian Imprint Regulator, Ctcf, Maintains The Maternal Genomic Imprint In Drosophila Melanogaster, William A. Macdonald, Debashish Menon, Nicholas J. Bartlett, G Elizabeth Sperry, Vanya Rasheva, Victoria Meller, Vett K. Lloyd

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

CTCF is a versatile zinc finger DNA-binding protein that functions as a highly conserved epigenetic transcriptional regulator. CTCF is known to act as a chromosomal insulator, bind promoter regions, and facilitate long-range chromatin interactions. In mammals, CTCF is active in the regulatory regions of some genes that exhibit genomic imprinting, acting as insulator on only one parental allele to facilitate parent-specific expression. In Drosophila, CTCF acts as a chromatin insulator and is thought to be actively involved in the global organization of the genome.

Results

To determine whether CTCF regulates imprinting in Drosophila, we generated CTCF mutant alleles …

Functional Analysis Of B And C Class Floral Organ Genes In Spinach Demonstrates Their Role In Sexual Dimorphism, D Noah Sather, Maja Jovanovic, Edward M. Golenberg

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Evolution of unisexual flowers entails one of the most extreme changes in plant development. Cultivated spinach, Spinacia oleracea L., is uniquely suited for the study of unisexual flower development as it is dioecious and it achieves unisexually by the absence of organ development, rather than by organ abortion or suppression. Male staminate flowers lack fourth whorl primordia and female pistillate flowers lack third whorl primordia. Based on theoretical considerations, early inflorescence or floral organ identity genes would likely be directly involved in sex-determination in those species in which organ initiation rather than organ maturation is regulated. In this …

Meiotic Dna Re-Replication And The Recombination Checkpoint, Nicole Ann Najor

Wayne State University Dissertations

Progression through meiosis occurs through a strict sequence of events, so that one round of DNA replication precedes programmed recombination and two nuclear divisions. Cyclin dependent kinase 1 (Cdk1) is required for meiosis, and any disruption in its activity leads to meiotic defects. The Cdk1 inhibitor, Sic1, regulates the G1-S transition in the mitotic cell cycle and the analogous transition in meiosis. We have employed a form of Sic1, Sic1deltaP^HA, that is mutated at multiple phosphorylation sites and resistant to degradation. Meiosis specific expression of Sic1deltaP^HA disrupts Cdk1 activity and leads to significant accumulation of over replicated …

Analysing The Effects Of Loss Of Sin3 In Drosophila Melanogaster, Aishwarya Swaminathan

Wayne State University Dissertations

Sin3A has been previously shown to be an essential gene for Drosophila viability and is implicated in the regulation of cell cycle. In this study, we show that SIN3 is not only required for embryonic viability but also for post-embryonic development. Genetic analysis suggests that the different isoforms of SIN3 may regulate unique sets of genes during development. The developmental lethality occurring due to ubiquitous knock down of SIN3 is hypothesized to be to the result of defects in cell proliferation. Conditional knock down of SIN3 in the wing discs results in a curly wing phenotype in the adult fly. …

Determination Of The Essential Functions Of A Conserved Cyclin, Cyclin Y, In Drosophila, Dongmei Liu

Wayne State University Dissertations

The Drosophila gene CG14939 encodes a member of a highly conserved family of cyclins, the Y type cyclins, which have not been functionally characterized in any organism. Here I report the generation and phenotypic characterization of a null mutant of CG14939, which we rename Cyclin Y (CycY). I show that the null mutant, CycY^E8, is homozygous lethal with most mutant animals arresting during pupal development. The mutant exhibits delayed larval growth and major developmental defects during metamorphosis. Heat shock-induced expression of CycY at different times during development resulted in variable levels of rescue, the timing …

Towards An Understanding Of The Etiology Of Abdominal Aortic Aneurysms: Identification Of Genes Implicated In Aaa Risk And Development, John Hunt Lillvis

Wayne State University Dissertations

Abdominal aortic aneurysm (AAA) is a common disease for which mechanisms of formation are still not well understood. Despite a strong genetic component to AAA risk, specific risk alleles are still largely unidentified. AAA is also a localized disease with a majority occurring in the infrarenal abdominal aorta and is six times more common than aneurysms of the thoracic aorta. To determine whether risk alleles are present in functional positional candidate genes. we: 1. performed a genetic association study using DNA from AAA cases and controls in ten candidate genes and 2. performed exon sequencing on three genes with evidence …

Tracking Profiles Of Genomic Instability In Spontaneous Transformation And Tumorigenesis, Lesley Lawrenson

Wayne State University Dissertations

The dominant paradigm for cancer research focuses on the identification of specific genes for cancer causation and for the discovery of therapeutic targets. Alternatively, the current data emphasize the significance of karyotype heterogeneity in cancer progression over specific gene-based causes of cancer. Variability of a magnitude significant to shift cell populations from homogeneous diploid cells to a mosaic of structural and numerical chromosome alterations reflects the characteristic low-fidelity genome transfer of cancer cell populations. This transition marks the departure from micro-evolutionary gene-level change to macro-evolutionary change that facilitates the generation of many unique karyotypes within a cell population. Considering cancer …