Digital Commons Network^™

Network Analysis And Comparative Phylogenomics Of Micrornas And Their Respective Messenger Rna Targets Using Twelve Drosophila Species, M Ryan Woodcock

Theses and Dissertations

MicroRNAs represent a special class of small (~21–25 nucleotides) non-coding RNA molecules which exert powerful post-transcriptional control over gene expression in eukaryotes. Indeed microRNAs likely represent the most abundant class of regulators in animal gene regulatory networks. This study describes the recovery and network analyses of a suite of homologous microRNA targets recovered through two different prediction methods for whole gene regions across twelve Drosophila species. Phylogenetic criteria under an accepted tree topology were used as a reference frame to 1) make inference into microRNA-target predictions, 2) study mathematical properties of microRNA-gene regulatory networks, 3) and conduct novel phylogenetic analyses …

Genetic Analysis Of The Function Of The Drosophila Doublesex-Related Factor Dmrt93b, Diana O'Day

Dissertations & Theses (Open Access)

DMRT (Doublesex and Mab-3 related transcription factor) proteins generally associated with sexual differentiation in many organisms share a common DNA binding domain and are often expressed in reproductive tissues. Aside from doublesex, which is a central factor in the regulation of sex determination, Drosophila possesses three different dmrt genes that are of unknown function. Because the association with sexual differentiation and reproduction is not universal and some DMRT proteins have been found to play other developmental roles we chose to further characterize one of these Drosophila genes. We carried out genetic analysis of dmrt93B, which was previously found to be …

Damage-Induced Inflammation And Nociceptive Hypersensitivity In Drosophila Larvae, Daniel T. Babcock

Dissertations & Theses (Open Access)

Mounting an effective response to tissue damage requires a concerted effort from a number of systems, including both the immune and nervous systems. Immune-responsive blood cells fight infection and clear debris from damaged tissues, and specialized pain receptors become hypersensitive to promote behavior that protects the damaged area while it heals. To uncover the cellular and molecular mechanisms underlying these processes, we have developed a genetically tractable invertebrate model of damage-induced inflammation and pain hypersensitivity using Drosophila larvae.

To study wound-induced inflammation, we generated transgenic larvae with fluorescent epidermal cells and blood cells (hemocytes). Using live imaging, we monitored the …

The Role Of Ecdysone Signaling In Fat-Body Tissue Remodeling And Pupal Metabolism, Nichole Dinell Bond

UNLV Theses, Dissertations, Professional Papers, and Capstones

Holometabolous insects undergo an astonishing transition during their development. During metamorphosis, the larva dramatically changes form and becomes an adult fly. During this process obsolete larval tissues must be eliminated, while tissues required for further development are retained and often remodeled to meet the needs of the adult fly. Tissue remodeling is characterized by morphological changes of the cells in a tissue mass. In many cases, remodeling is characterized by dissociation of the tissue mass, releasing cells to move freely around the body cavity. This process is also common in wound healing and is a key feature of human disease …

Mechanisms Associated With Aging And Age-Related Disease In Drosophila, Melanie Jones

Theses and Dissertations

Aging is an intrinsic process that is independent of obvious disease. In contrast to normal aging, age-related diseases are conditions that typically manifest at advanced ages, are associated with explicit pathology and cause disability and premature death. We used Drosophila as a model to investigate the molecular-genetic mechanisms associated with aging and age-related disease. Age-related locomotor impairment (ARLI) is a serious condition for the elderly and greatly impacts their quality of life. Toward identifying genes and mechanisms that influence ARLI, we performed a forward genetic screen using Drosophila mutants. This screen identified a loss of function mutant in PDK1, a …

Analysis Of The Crmp Gene In Drosophila: Determining The Regulatory Role Of Crmp In Signaling And Behavior, Deanna Hardt Morris

University of Kentucky Doctoral Dissertations

The mammalian genome encodes five collapsin response mediator protein (CRMP) isoforms. Cell culture studies have shown that the CRMPs mediate growth cone dynamics and neuron polarity through associations with a variety of signal transduction components and cytoskeletal elements. CRMP is also a member of a protein family including the presumably ancestral dihydropyrimidinase (DHP) protein that catalyzes the second step in pyrimidine degradation. In Drosophila, CRMP and DHP proteins are produced by alternatively spliced transcripts of the CRMP gene. The alternative protein forms have a 91% sequence identity, but unique expression patterns. CRMP is found exclusively in neuronal tissues and …

Drosophila Nicotinamidase And Sir2 In Longevity Regulation And Oxidative Stress Response, And The Implications For Aging Theory, Gregory Miller

Wayne State University Dissertations

The protein deacetylase Sir2 has been shown to increase lifespan in a variety of organisms, possibly through its ability to engender the effects of dietary restriction. The Drosophila nicotinamidase DNAAM increases lifespan in a Sir2 dependant manner, and may play a role in oxidative stress resistance. Oxidative damage that accumulates in cells during normal aging contributes to a variety of diseases and pathologies, and can result in an increase in age specific mortality. Accordingly, the oxidative stress theory of aging predicts that organisms with an increased tolerance to oxidative damage will have an increased longevity, while organisms with decreased tolerance …

Role Of Drosophila Rap/Fzr (Cdh1) In Retinal Axon Targeting And Its Interactions With Loco, Liprin-A And Ras, Marta Gronska

Dissertations and Theses

The development of the wild type Drosophila compound eye involves stereotypical targeting of photoreceptor axons to the specific layers of the optic ganglion, medulla and lamina, in the third instar larvae. To test the hypothesis that ubiquitin ligases play an important role during retinal axon targeting we have examined the patterns of axon targeting in the developing eye of the retina aberrant in pattern (rap/fzr) mutants. Rap/Fzr is a homolog of mammalian Cdh1, an activator of anaphase promoting complex (APC), an E3 ubiquitin ligase. Previous work has shown that Rap/Fzr is required in cell cycle regulation, glia differentiation and pattern …

Use-Dependent Plasticity Regulates Sleep Need In Drosophila Melanogaster, Jeffrey Donlea

All Theses and Dissertations (ETDs)

Although the necessary functions of sleep have not been identified, sleep has been shown to play an important role in the consolidation of memories. Recent studies have shown that, in addition to playing a strong role in sleep regulation, the circadian clock also influences processes associated with learning and memory. Thus, the neural circuits that control circadian rhythms are uniquely positioned to play an important role in coordinating interactions between sleep and memory. Drosophila melanogaster exhibit increased sleep following several days of social experience and require sleep to consolidate long-term memories: LTM) after Courtship Conditioning, an associative memory assay. We …

The Differential Roles Of D-Pax2 Variants In Regulating Drosophila Eye And Bristle Development, Colin J. O’Shea

Honors Theses

The ability to appropriately interact with the environment is crucial to an organism’s survival. The establishment of functional sensory systems, such as the bristles and eyes in Drosophila, is a critical event during the development of the organism. The transcription factor D Pax2 is involved in the differentiation of the shaft and glial cells in the developing bristle (Kavaler et al., Dev, 126:2261-2272, 1999) and of the cone and primary pigment cells in the developing eye (Fu and Noll, Genes Dev, 11:389-405, 1997). How D-Pax2 contributes to distinct differentiative pathways in different cell types is not known. Recent work by …

Identification And Characterization Of Downstream Target Genes Of The Bmp Signaling Pathway, Nam Chul Kim

All ETDs from UAB

During nervous system development, neurons proliferate, differentiate, project their axons to their targets and make synapses with them. At the neuromuscular junction of Drosophila, these functional synapses enlarge as the body grows to maintain physiologically effective synaptic transmission with the muscles. Drosophila Bone Morphogenetic Protein (BMP) type II receptor, Wishful thinking (Wit), is important in this proper synaptic growth and function. To identify transcriptional targets of Wit signaling, we performed microarray experiments comparing normal controls to wit mutants. Through this study, we found that some of the verified target genes showed isoform-specific regulation in wit mutants, and that several neuropeptide …

The Overexpression Of Homeotic Complex Gene Ultrabithorax In The Post-Embryonic Neuronal Lineages Of The Ventral Nervous System In Drosophila Melanogaster, Katie Dry

Master’s Theses

This study uses a molecular technique called MARCM (Mosaic Analysis with a Repressible Cell Marker) to label neuronal lineages that overexpress the Hox gene Ultrabithorax (Ubx) in an unlabeled, wild type background. The results indicate that the overexpression of Ubx is sufficient to transform more anterior neuronal lineages to themorphology of their more posterior counterparts. The data presented here begin to elucidate the role that the Hox genes have in shaping segment-specific neural connections in the post-embryonic ventral nervous system.

Lim Kinase 1 And Twinstar In Synaptic Plasticity Of Drosophila Motoneurons, James Brian Machamer

All ETDs from UAB

Modification of the actin cytoskeleton is essential for synaptic plasticity, which is believed to underlie the brain's capacity for learning and memory. Regulation of the actin cytoskeleton by LIM Kinases (LIMK1 and LIMK2) and their downstream targets Actin Depolymerization Factor/Cofilin (ADF/Cofilin) in the mouse forebrain modulates dendritic spine morphology, synaptic function, long-term potentiation (LTP), and learning and memory, but appear dispensable for the regulation of most forms of presynaptic plasticity. However, these analyses were performed in mice mutant for single members of these gene families, and thus the interpretation of these results is confounded by potential compensatory activity of homologous …