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Cloning And Expression Of A Tobacco Stearoyl-Acp Desaturase Gene Sbip24 And Its Interaction With Sabp2 In Sa Pathway, Amin J. Ferdous

Electronic Theses and Dissertations

Salicylic acid binding protein 2 (SABP2) that converts methyl salicylate to salicylic acid (SA) plays an obligatory role in the SA-mediated disease resistance pathway in plants. SABP2 interacts with SBIP24 in a yeast two-hybrid screening. SBIP24 belongs to the stearoyl-acyl carrier protein-desaturase protein family. To biochemically characterize the SBIP24, it was cloned from tobacco leaves using RT-PCR and expressed in E. coli. Recombinant SBIP24 was affinity purified using Ni-NTA chromatography. RT-PCR was performed to determine the role of SABP2 in modulating the expression SBIP24. TMV infected transgenic C3 (control tobacco plant containing empty silencing vector) and 1-2 (SABP2-silenced) …

Characterization Of A Putative Phospholipase D ´ Like Gene As A Lipid Signaling Modulator And Its Role In Salicylic Acid Mediated Defense Pathway In Nicotiana Tabacum, Phillip T. Dean

Electronic Theses and Dissertations

Plants are in a perpetual evolutionary arms race with a wide range of pathogens. Their sessile nature has led plants to evolve defense mechanisms that can quickly recognize a unique stressor and deploy a resistance tailored for a specific attack. The salicylic acid (SA) mediated defense pathway has been shown to be one of the major defense tactics plants can initiate to defend themselves against microbial pathogens. Following a pathogen attack high levels of methyl salicylate (MeSA) are produced that can be converted to SA by the enzyme salicylic acid binding protein 2 (SABP2). A yeast two-hybrid screening was performed …

Biochemical Characterization Of Sbip-470 And Its Role In Sa-Mediated Signaling In Plants, Danda P. Chapagai

Electronic Theses and Dissertations

Salicylic acid binding protein 2 (SABP2) is known to play a key role in Salicylic acid mediated defense pathway. SBIP-470 is SABP2 interacting protein that might be putatively involved in transfer of lipids. SBIP-470 was cloned without the signal peptide and expressed in E. coli. In vitro lipid binding assay using recombinant SBIP-470 failed to detect lipid binding. In vitro lipid transfer assay showed recombinant SBIP-470 does not transfer phospholipid. Study has shown that SBIP-470 is highly inducible upon infection with viral as well as bacterial pathogens. Induction of SBIP-470 expression upon the TMV infection most likely depends upon …

The Vascular Flora Of Steele Creek Park And A Quantitative Study Of Vegetation Patterns In Canopy Gaps, Sullivan County, Tennessee, Phillip C. Klahs

Electronic Theses and Dissertations

An inventory of vascular plants was conducted in Steele Creek Park in Sullivan County, Tennessee from March 2013 to September 2014. The park covers an area of 892 ha and lies within the Ridge and Valley Province. The inventory of vascular plants documented 547 species of 323 genera and 101 families. Two hundred sixteen taxa were newly reported for Sullivan County. Tennessee Special Concern Species included Cardamine rotundifolia, Castanea dentata, Lonicera dioica, Allium tricoccum, Cypripedium acaule, and Panax quinquefolius. A single species, Juglans cinerea L., is considered a Tennessee Threatened Species. Vegetation patterns were studied quantitatively by installing 10 …

Earthworm, Microbial Biomass, And Leaf Litter Decay Responses After Invasive Honeysuckle Shrub Removal From Urban Woodlands., Robert Preston Pipal

Electronic Theses and Dissertations

Invasive species are one of the leading causes of biodiversity loss and their presence can significantly impact the structure and function of native ecosystems. In this dissertation, the impacts of the invasive honeysuckle shrub, Lonicera maackii, on exotic earthworm populations, leaf litter decay responses, and inorganic and organic nutrient pools in an urban woodland park are assessed. Chapter 1 provides a brief review of honeysuckle's effects on forest ecosystems. Chapter 2 describes honeysuckle’s effects on exotic earthworm populations and the seasonal importance of macroinvertebrates to leaf litter decomposition in urban woodlands. This study revealed that L. maackii promoted higher exotic …

Identification, Cloning, And Expression Of Tobacco Responsive To Dehydration Like Protein (Rd22), Sbip-355 And Its Role In Sabp2 Mediated Sa Pathway In Plant Defense, Hanadi Abdulaali Almazroue

Electronic Theses and Dissertations

Abscisic acid (ABA) induces RD22, responsive to dehydration stress gene. Salicylic acid (SA) has been the focus of research due to its role against pathogens and abiotic stress. Interaction between ABA and SA signaling pathways is still poorly understood. SA-Binding Protein 2 (SABP2) converts methyl salicylate to SA. An attempt was made to identify proteins that interact with SABP2 using a yeast 2-hybrid screening. Several interactors were identified. One of them, SA-Binding Protein 2 Interacting Protein-355 (SBIP-355), showed high homology to RD22. Bioinformatic approaches showed that SBIP-355 contains a BURP domain. Phylogenetic analysis reveals that SBIP-355 clustered into the …

Development And Testing Of A Rapid Multiplex Assay For The Identification Of Biological Stains, Kevin M. Legg

Electronic Theses and Dissertations

While DNA profiling makes it possible to individualize biological stains, the identification of the stain itself can present forensic serologists with a significant challenge. Current antibody- and enzyme activity-based assays used by forensic practitioners for biological stain identification yield only presumptive results. Positive results with non-target body fluids or cross-reactivity with non-human sources has also been well documented. Some tests can consume unacceptable quantities of precious evidence while for some body fluids (vaginal fluid and menstrual blood) there are simply no available tests at all.

This research presented here aims to develop and rigorously test a fast, accurate, and sensitive …

Northern Saw-Whet Owl (Aegolius Acadicus) Abundance And Distribution In The Southern Appalachian Mountains Of Northeast Tennessee, John P. Mccormick

Electronic Theses and Dissertations

Little is known about the distribution, abundance, or life histories of the Northern Saw-whet Owl (Aegolius acadicus) in the Southern Appalachian Mountains of Northeast Tennessee. This study relied upon the Pennsylvania Protocol of audio playback of a Northern Saw-whet Owl call to monitor for owl presence at various areas above 3,500 feet in elevation. Owls were found at multiple areas in Northeast Tennessee, including Roan Mountain, Unaka Mountain, Rocky Fork, and the Pond Mountain Area. Statistical analysis revealed that these owls were not limited by habitat, showing equal presence in Hardwood habitats along with Spruce and/or Fir habitats. …

An Agent-Based Model Of Ant Colony Energy And Population Dynamics: Effects Of Temperature And Food Fluctuation, Guo Xiaohui

Electronic Theses and Dissertations

The ant colony, known as a self-organized system, can adapt to the environment by a series of negative and positive feedbacks. There is still a lack of mechanistic understanding of how the factors, such as temperature and food, coordinate the labor of ants. According to the Metabolic Theory of Ecology (MTE), the metabolic rate could control ecological process at all levels. To analyze self-organized process of ant colony, we constructed an agent-based model to simulate the energy and population dynamics of ant colony. After parameterizing the model, we ran 20 parallel simulations for each experiment and parameter sweeps to find …

Production Of An Antibiotic-Like Activity By Streptomyces Sp. Couk1 Under Different Growth Conditions, Olaitan G. Akintunde

Electronic Theses and Dissertations

Streptomyces are known to produce a large variety of antibiotics and other bioactive compounds with remarkable industrial importance. Streptomyces sp. COUK1 was found as a contaminant on a plate in which Rhodococcus erythropolis was used as a test strain in a disk diffusion assay and produced a zone of inhibition against the cultured R. erythropolis. The identity of the contaminant was confirmed as Streptomyces through 16S rRNA sequencing. This Streptomyces produces a strong inhibitory compound in different growth media. A culture extract from inorganic salts starch agar was found to be very active; producing a large zone of inhibition …

Neogene Climate Change In Eastern North America: A Quantitative Reconstruction, Kyrie A. Baumgartner

Electronic Theses and Dissertations

Though much is known of the global paleoclimate during the Neogene, little is understood about eastern North America at that time. During the Neogene the global paleoclimate was transitioning from the warm temperatures and higher levels of precipitation of the Paleogene to the cooler temperatures and lower levels of precipitation during the Pleistocene. Eleven fossil sites from Neogene eastern North America were analyzed using the Coexistence Approach: Pollack Farm, Brandon Lignite, Legler Lignite, Alum Bluff, Bryn Mawr, Big Creek on Sicily Island, Brandywine, Gray Fossil Site, Citronelle, Peace Creek, and Ohoopee River Dune Field. Analyses showed a general trend that …

Adaptive Strategies For Foraging And Their Implications For Flower Constancy, Or: Do Honey Bees Multitask?, Ashley E. Wagner

Electronic Theses and Dissertations

Classical experiments on honey bee time-memory showed that foragers trained to collect food at a fixed time of day return the following day with remarkable time-accuracy. Previous field experiments revealed that not all foragers return to a food source on unrewarded test days. Rather, there exist 2 subgroups: “persistent” foragers reconnoiter the source; “reticent” foragers wait in the hive for confirmation of source availability. To examine how these foragers contribute to a colony’s ability to reallocate foragers across sources with rapidly changing availabilities, foragers were trained to collect sucrose during a restricted window for several days and observed over 3 …

Invasive Plants As Drivers And Passengers Of Community Change In A Disturbed Urban Forest., Jeffery A. Masters

Electronic Theses and Dissertations

Invasive species can impact local ecosystems by decreasing biodiversity and local abundances of native species. Invasive species also frequently establish in disturbed habitats. An invasive species may dominate a habitat because the introduced species is a superior competitor (driver model) for resources or because the introduced species is more tolerant of noncompetitive processes such as anthropogenic disturbance that reduces the diversity and abundance of native species (passenger model). Ranunculus ficaria (Ranunculaceae) is an invasive plant species in the northeastern United States, and can be especially dense in urban riparian habitats. It emerges early and forms thick mats of vegetation that …

Paleozoic Seed Bank And Their Ecological Significance, Petra Seka Yehnjong

Electronic Theses and Dissertations

Soil seed banks are a reservoir of viable seeds present in the soil in plant communities. They have been studied and characterized in various ways in different habitats. However, these studies are limited to modern seed banks. This study extends seed bank studies to the Paleozoic Era. It was hypothesized that size distribution and seed density in Paleozoic seed banks exhibit similar patterns as in modern seed banks. Seed sizes and seed density of fossil seed from Wise Virginia were estimated. Modern seed bank information was obtained from published data. Data were analyzed using one-way ANOVA and Kruskal-Wallis test. The …

Subcloning, Expression And Purification Of Functional E. Coli Nucleotide Excision Repair Protein Uvra Using Impact-Cn System, Cathy W. Lin Mrs

Electronic Theses and Dissertations

DNA in cells is constantly damaged by both endogenous and exogenous genotoxic agents. DNA repair is a cellular machinery that counters DNA damage and thus preserve genome integrity. Nucleotide excision repair (NER) in Escherichia coli (E. coli) is one of the DNA repair systems that recognizes and removes a variety of DNA damage such as pyrimidine dimers, bulky chemical adducts, DNA intrastrand cross-links, etc. The genes responsible for E. coli NER incisions are UvrA, UvrB, and UvrC. As the first step of E. coli NER, DNA damage recognition is achieved through the UvrA₂B …

A Time-Course Analysis Of Behavioral Plasticity And Differential Gene Expression Patterns In Response To Density In Schistocerca Americana (Orthoptera: Acrididae), Steven Gotham

Electronic Theses and Dissertations

Phenotypic plasticity is the ability of the genotype to express alternative phenotypes in response to different environmental conditions and this is considered to be an adaptation in which a species can survive and persist in a rapidly changing environment. Some grasshoppers and locusts are capable of expressing an extreme form of density-dependent phenotypic plasticity, known as locust phase polyphenism. At low population density, the individuals typically have a cryptic coloration as nymphs, are less active, and only seek out conspecifics for reproductive purposes. At high density, however, they develop a drastically different phenotype in which they have a conspicuous coloration, …

Effects Of Weaning Age On Body Composition And Growth Of Ex Situ California Sea Lion (Zalophus Californianus) Pups, Brandon Davis

Electronic Theses and Dissertations

Pinnipeds exhibit a wide range of lactation strategies that vary from just a few days to nearly three years in duration. Phocids have a relatively short, intense nursing period culminating with weaning after just a few days or weeks, while dependent otariids generally take several months of consuming a combined milk and solid food diet before being completely independent. The transition to nutritional independence can be particularly challenging for newly weaned pups, which must adjust to behavioral, physiological and nutritional changes as a milk diet is replaced with solid food. An interruption in energy resources during this formative stage could …

Integral Projection Models Reveal Interactive Effects Of Biotic Factors And Disturbance On Plant Demography, Matthew Tye

Electronic Theses and Dissertations

Understanding factors limiting population growth is crucial to evaluating species persistence in changing environments. I used Integral Projection Models (IPMs) to elucidate the role of biotic interactions and disturbance on population growth rate in two plants: Helianthemum squamatum, a perennial endemic to gypsum habitats in central Spain, and Liatris ohlingerae, a long-lived perennial endemic to the Lake Wales Ridge of central Florida. In H. squamatum, there was a strong positive effect of trampling in the site with the highest plant density and moderate positive effects of seed addition in the site with the lowest plant density. Differences in treatment effectiveness …

Effects Of Biotic Interactions On Coastal Wetland Communities With Applications For Restoration, Melinda Donnelly

Electronic Theses and Dissertations

Coastal wetland plants serve as ecological engineers in a physiologically stressful environment and the loss of coastal wetlands can cause negative effects throughout the estuarine system. Due to increased degradation of coastal habitats worldwide, interest in restoration has increased around the world. An understanding of the biotic processes affecting species distribution and diversity is critical for future conservation, management, and restoration of coastal wetlands. The purpose of my study was to test the effects of biotic interactions on native coastal wetland plants and determine how these interactions may be incorporated into current and future restoration projects. I had three primary …

Using Land Cover Mapping And Landscape Metrics To Evaluate Effects Of Urban Development On Ecological Integrity In Florida, Michael Gilbrook

Electronic Theses and Dissertations

The widespread loss and degradation of habitat constitutes the largest threat to biodiversity in North America. While regulatory programs such as the Endangered Species Act of 1973 and wetland permitting under the Clean Water Act have addressed acute assaults on critical habitat, large areas of unprotected uplands have been lost. Urban development, particularly the advent of lower density suburban and rural sprawl, has greatly diminished the extent of contiguous patches of forest habitat and introduced a host of other undesirable effects on ecosystem function. This study sought to evaluate the extent of urban sprawl and its effects on ecological integrity …

The Effects Of Non-Native Species On Two Life-Stages Of The Eastern Oyster Crassostrea Virginica, Wei Yuan

Electronic Theses and Dissertations

Since their recent introductions into Florida waters, three nonnative species [Perna viridis Linnaeus, 1758 (Asian green mussel), Mytella charruana d'Orbigny, 1846 (charru mussel) and Megabalanus coccopoma Darwin, 1854 (pink titan acorn barnacle)] have expanded both north and south along the Atlantic coast. Very little research has been done to understand how these nonnative species interact with the native eastern oyster (Crassostrea virginica Gmelin, 1791), which is a keystone species that provides important ecological services and economic benefits. To test the potential effects of P. viridis, M. charruana and M. coccopoma on C. virginica, I addressed the following questions: 1a) Does …

Migratory Connectivity And Carry-Over Effects In Northwest Atlantic Loggerhead Turtles (Caretta Caretta, L.), Simona Ceriani

Electronic Theses and Dissertations

Migration is a widespread and complex phenomenon in nature that has fascinated humans for centuries. Connectivity among populations influences their demographics, genetic structure and response to environmental change. Here, I used the loggerhead turtle (Caretta caretta, L.) as a study organism to address questions related to migratory connectivity and carry-over effects using satellite telemetry, stable isotope analysis and GIS interpolation methods. Telemetry identified foraging areas previously overlooked for loggerheads nesting in Florida. Next, I validated and evaluated the efficacy of intrinsic markers as a complementary and low cost tool to assign loggerhead foraging regions in the Northwest Atlantic Ocean (NWA), …

Physiological Constraints On Warm-Water Habitat Site Selection And Utilization By The Florida Manatee (Trichechus Manatus Latirostris) In East Central Florida, Ann Spellman

Electronic Theses and Dissertations

Living at the northern limits of its geographic range, the Florida manatee is particularly susceptible to cold stress-related mortality during the winter months, with most deaths occurring in the lower two-thirds of the state. Contributing to this cold stress susceptibility is the manatee's limited physiological and behavioral responses available when thermally stressed. While capable of migrating south in response to falling water temperatures, manatees must still find warm water when ambient river temperature drops below 20°C for more than a few days. This is in part due to the species low metabolic rate, limited capacity for thermogenesis, and limited ability …

Effects Of Mechanical Habitat Disturbance On The Diversity And Network Structure Of Plant-Bee Interaction Networks In Central Florida, Karlie Carman

Electronic Theses and Dissertations

Ecological interactions within a community shape the structure of ecosystems and influence ecosystem function. Plant-pollinator interactions exist as mutualistic exchange networks that may collapse as habitat loss occurs, thereby threatening the overall health of an ecosystem. Understanding the impacts of human-mediated habitat disturbance on ecological interactions is therefore crucial for conservation efforts. Archbold Biological Station (ABS) in Venus, Florida contains over 2000 hectares of protected Florida scrub habitat nested within a human-dominated environment that is threatened by anthropogenic habitat disturbance. In past studies, over 113 bee species and 157 associated host plants, many endemic to the Lake Wales Ridge, have …

Evaluation Of The Three-Dimensional Patterns And Ecological Impacts Of The Invasive Old World Climbing Fern (Lygodium Microphyllum), Alexis Maldonado

Electronic Theses and Dissertations

Invasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources available to other species present. Quantifying the structural changes due to the presence of this species has proved logistically difficult, especially on a large spatial …

Rala And Rab8 Regulate Drosophila Embryogenesis, Zhongyuan Zuo

Electronic Theses and Dissertations

Pseudocleavage furrow dynamics initiate at cycle 10 to help with mitotic divisions that lack cytokinesis. Permanent furrows then form at the beginning of cellularization (cycle 14). Cytoskeletal networks such as F-actin and non-muscle Myosin II have been demonstrated to be required for furrow formation and provide anchor points for chromosomal segregation. However, what drives the onset of furrow formation and membrane addition remains largely unclear. In my thesis, I have explored RalA and Rab8 function during furrow formation at metaphase and cellularization stages. These furrows are critical for correct chromosomal segregation, while disruption of furrow formation results in severe developmental …

Activity-Regulated Micrornas: Modulators Of Synaptic Growth At The Drosophila Neuromuscular Junction, Katherine Ruth Nesler

Electronic Theses and Dissertations

It is well established that long-term changes in synaptic structure and function are mediated by rapid activity-dependent gene transcription and new protein synthesis. A growing body of evidence supports the involvement of the microRNA (miRNA) pathway in these processes. We have used the Drosophila neuromuscular junction (NMJ) as a model synapse to characterize activity-regulated miRNAs and their important mRNA targets. Here, we have identified five neuronal miRNAs (miRs-1, -8, -289, -314, and -958) that are significantly downregulated in response to neuronal activity. Furthermore we have discovered that neuronal misexpression of three of these miRNAs (miR-8, -289, and -958) is capable …

Post-Transcriptional Shaping Of Neurons: The Role Of Mirnas And Fmrp-Interacting P-Body Components In Regulating Neuronal Structure, Breanna Symmes

Electronic Theses and Dissertations

Changes in synaptic structure in response to neuronal stimulation are believed to underlie the processes of learning and long-term memory. However, the mechanisms for these structural modifications are poorly understood. It is well-known that activity-dependent synaptic modifications rely upon new protein synthesis, and rapid new protein synthesis, at that. Therefore, it is widely believed that pools of messenger RNAs held in a state of translational repression are transcribed in a neuronal cell body prior to stimulation, and transported to the synapse, where they reside until stimulation occurs.

This study investigates the roles and interactions of translational repression mechanisms to better …

Regulators Of Repo: A Search For Gcm/Repo Transcription Factors, Kathy Ann Nipper

Electronic Theses and Dissertations

The role of the Drosophila melanogaster gene glial cells missing (gcm) is that of a binary switch in both the central nervous system (CNS) and the peripheral nervous system (PNS) in specification of the glial fate for multipotent precursor cells. However, Gcm is also essential for maturation of hematocytes and tendon cells ( Alfonso and Jones, 2002; Jones, et al., 1995; Hosoya et al., 1995; Soustell et al., 2004). The varied outcomes of gcm expression imply the interaction of co-factors capable of giving the Gcm protein different "meanings" in different developmental contexts. The Gcm target repo is expressed exclusively in …

Movements, Fishery Interactions, And Unusual Mortalities Of Bottlenose Dolphins, Steven Shippee

Electronic Theses and Dissertations

Bottlenose dolphins inhabiting coastlines and estuaries in Florida have been impacted in the past decade by development, algal blooms, catastrophic pollution, and fishery interactions (FI). Dolphins react to disturbance and environmental stressors by modifying their movements and habitat use, which may put them in jeopardy of conflict with humans. FI plays an increasing role in contributing to dolphin mortalities. I investigated dolphin movements, habitat use, residency patterns, and frequency of FI with sport fishing. Tagging studies with short-term data tags and bolt on radio-transmitters were done in several locations in Florida and the east coast providing fine-scale measurements of swimming, …