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Effects Of Drosophila Ribosomal Protein S6 Kinase On Wing Growth, M. J. Stewart, J. L. Hunt

Journal of the Arkansas Academy of Science

In multicellular animals, organ size, cell size and total organism size are regulated by signaling through the insulin receptor and TOR signaling pathways. The ribosomal protein S6 kinase is a key component of these pathways. It has been shown that mice or Drosophila lacking this kinase have a reduced body size that is associated with a decrease in cell size. Ectopic expression of activated or dominant negative transgenic variants of the Drosophila homolog of ribosomal S6 kinase (dS6K) has been shown to cause phenotypes that are consistent with a role for dS6K in growth, but whether the phenotypes were due …

Patterns Of Gene Expression In Microarrays And Expressed Sequence Tags From Normal And Cataractous Lenses, Konstantinos Sousounis, Panagiotis A. Tsonis

Biology Faculty Publications

In this contribution, we have examined the patterns of gene expression in normal and cataractous lenses as presented in five different papers using microarrays and expressed sequence tags. The purpose was to evaluate unique and common patterns of gene expression during development, aging and cataracts.

Lens Regeneration In Axolotl: New Evidence Of Developmental Plasticity, Rinako Suetsugu-Maki, Nobuyasu Maki, Saulius Sumanas, Jie Zhu, Katia Del Rio-Tsonis, Panagiotis A. Tsonis

Biology Faculty Publications

Background: Among vertebrates lens regeneration is most pronounced in newts, which have the ability to regenerate the entire lens throughout their lives. Regeneration occurs from the dorsal iris by transdifferentiation of the pigment epithelial cells. Interestingly, the ventral iris never contributes to regeneration. Frogs have limited lens regeneration capacity elicited from the cornea during pre-metamorphic stages. The axolotl is another salamander which, like the newt, regenerates its limbs or its tail with the spinal cord, but up until now all reports have shown that it does not regenerate the lens.

Conservation Of The Three-Dimensional Structure In Non-Homologous Or Unrelated Proteins, Konstantinos Sousounis, Carl E. Haney, Jin Cao, Bharath Sunchu, Panagiotis A. Tsonis

Biology Faculty Publications

In this review, we examine examples of conservation of protein structural motifs in unrelated or non-homologous proteins. For this, we have selected three DNA-binding motifs: the histone fold, the helix-turn-helix motif, and the zinc finger, as well as the globin-like fold. We show that indeed similar structures exist in unrelated proteins, strengthening the concept that three-dimensional conservation might be more important than the primary amino acid sequence.

Why Wasp Foundresses Change Nests: Relatedness, Dominance, And Nest Quality, Perttu Seppä, David C. Queller, Joan E. Strassmann

Biology Faculty Research

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a …

Amino Acid Repeats Cause Extraordinary Coding Sequence Variation In The Social Amoeba Dictyostelium Discoideum, Clea Scala, Xiangjun Tian, Natasha J. Mehdiabadi, Margaret H. Smith, Gerda Saxer, Katie Stephens, Prince Buzombo, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Protein sequences are normally the most conserved elements of genomes owing to purifying selection to maintain their functions. We document an extraordinary amount of within-species protein sequence variation in the model eukaryote Dictyostelium discoideum stemming from triplet DNA repeats coding for long strings of single amino acids. D. discoideum has a very large number of such strings, many of which are polyglutamine repeats, the same sequence that causes various human neurological disorders in humans, like Huntington’s disease. We show here that D. discoideum coding repeat loci are highly variable among individuals, making D. discoideum a candidate for the most variable …

Whole Genome Sequencing Of Mutation Accumulation Lines Reveals A Low Mutation Rate In The Social Amoeba Dictyostelium Discoideum, Gerda Saxer, Paul Havlak, Sara A. Fox, Michael A. Quance, Sharu Gupta, Yuriy Fofanov, Joan E. Strassmann, David C. Queller

Biology Faculty Research

Spontaneous mutations play a central role in evolution. Despite their importance, mutation rates are some of the most elusive parameters to measure in evolutionary biology. The combination of mutation accumulation (MA) experiments and whole-genome sequencing now makes it possible to estimate mutation rates by directly observing new mutations at the molecular level across the whole genome. We performed an MA experiment with the social amoeba Dictyostelium discoideum and sequenced the genomes of three randomly chosen lines using high-throughput sequencing to estimate the spontaneous mutation rate in this model organism. The mitochondrial mutation rate of 6.76×10(-9), with a Poisson confidence interval …

Structured Growth And Genetic Drift Raise Relatedness In The Social Amoeba Dictyostelium Discoideum, Neil J. Buttery, Chandra N. Jack, Boahemaa Adu-Oppong, Kate T. Snyder, Christoper R L Thompson, David C. Queller, Joan E. Strassmann

Biology Faculty Research

One condition for the evolution of altruism is genetic relatedness between altruist and beneficiary, often achieved through active kin recognition. Here, we investigate the power of a passive process resulting from genetic drift during population growth in the social amoeba Dictyostelium discoideum. We put labelled and unlabelled cells of the same clone in the centre of a plate, and allowed them to proliferate outward. Zones formed by genetic drift owing to the small population of actively growing cells at the colony edge. We also found that single cells could form zones of high relatedness. Relatedness increased at a significantly …

Mind The Gap: A Comparative Study Of Migratory Behavior In Social Amoebae, Owen M. Gilbert, Jennie J. Kuzdzal-Fick, David C. Queller, Joan E. Strassmann

Biology Faculty Research

Social amoebae aggregate to form a multicellular slug that migrates some distance. Most species produce a stalk during migration, but some do not. We show that Dictyostelium giganteum, a species that produces stalk during migration, is able to traverse small gaps and utilize bacterial resources following gap traversal by shedding live cells. In contrast, we found that Dictyostelium discoideum, a species that does not produce stalk during migration, can traverse gaps only when in the presence of other species’ stalks or other thin filaments. These findings suggest that production of stalk during migration allows traversal of gaps that commonly occurs …

Variation In Flight Morphology In A Damselfly With Female-Limited Polymorphism, Emily Jane Mctavish, Genevieve K. Smith, Rafael F. Guerrero, Eben Gering

Biology Faculty Articles

Background: Female-limited colour polymorphisms occur in many species of dragonflies and damselflies. Often one female morph appears male-like in coloration (androchromes) whereas one or more others are distinct from males (gynochromes). These androchromes are hypothesized to be male-mimics, thereby avoiding the harassment of excessive male mating attempts.

Organism: The damselfly Ischnura ramburii, Rambur’s forktail, is a widespread New World species with androchrome and gynochrome females. It was introduced to the Hawaiian Islands in the mid-1970s and females were thought to be exclusively gynochromatic there.

Questions: How do males and females differ in their flight apparatus? Do females with different …

Consequences Of Kleptoplasty On The Distribution, Ecology, And Behavior Of The Sacoglossan Sea Slug, Elysia Clarki, Michael Louis Middlebrooks

USF Tampa Graduate Theses and Dissertations

The sacoglossan sea slug Elysia clarki is able to photosynthesize for three to four months using chloroplasts sequestered from its algal food sources. Furthermore, the slug is able to store multiple chloroplasts from different algal species within the same cell. This research, consisting of several related studies, explores the role that provision of organic nutrients via photosynthesis plays in the biology of the slug. The first chapter demonstrates that, under conditions of starvation, photosynthetic activity in E. clarki remains fully functional for one month after which it then declines. During the first month of starvation the slug exhibits similar feeding …

Responses To Chemical Exposure By Foraminifera: Distinguishing Dormancy From Mortality, Benjamin James Ross

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon blowout in 2010 released an estimated 4.9 million barrels of crude oil into the Gulf of Mexico in the 83 days between the initial explosion and the capping of the well. Response included extensive use of Corexit© oil dispersant. Although South Florida was spared exposure by currents, this event highlights the need for effective bioassay organisms for coral reefs. Amphistegina spp. are benthic foraminifers that host diatom symbionts in a relationship similar to that of coral and their zooxanthellae. Amphistegina spp. occur abundantly in reef communities nearly worldwide, are easily collected and maintained in culture, and are …

Snowy Plover Buried Alive By Wind-Blown Sand, J. Daniel Farrar, Adam A. Kotaich, David J. Lauten, Kathleen A. Castelein, Eleanor P. Gaines

Institute for Natural Resources Publications

Brief description of an encounter with a Snowy Plover discovered at a nest site near the mouth of Tahkenitch Creek in Douglas County, Oregon. The plover was buried up to its neck in sand, presumably caused by high winds. The article describes the authors' efforts to resuscitate the plover.

In Vivo Quantification Of Reactive Oxygen Species Demonstrates High Levels Of Oxidative Stress In Base Excision Repair-Deficient Caenorhabditis Elegans: Implications For Associative Metabolic Phenotypes, Travis Lee Hase

University Honors Theses

In this present study, I use C. elegans as a model organism to better characterize the phenotypic response to deficiencies in base excision repair (BER). This will help to elucidate how DNA damage, increased mutagenesis, and exposure to reactive oxygen species (ROS) is related to Metabolic Syndrome. Additionally, this work will establish a starting point for investigation that can further characterize phenotypic responses such as mitochondrial physiology and morphology through measurements of mitochondrial membrane potential and mitochondrial circularity. The overall goal of this research is to better understand the nature of mitochondrial dysfunction with respect to the inactivation of DNA …

Full Issue: Volume 6, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.

Analysis Of Hpv-16 Late Gene Expression, Beatrice Orru

Doctoral

Human papillomaviruses (HPVs) are present in 99.7% of all cervical cancers and HPV type 16 (HPV-16) is the major cause of cervical cancer. Expression of the viral capsid gene L1 and L2 can be detected only in the terminally epithelial cells and we speculate that inhibition of HPV-16 late gene expression in the early stage of the life cycle is probably a prerequisite for persistence of infection. The products of the late genes, L1 and L2, are highly immunogenic and expression of these proteins in the lower layers of the cervical epithelium could lead to clearance of the virus. Therefore, …

Inhibition Of L-Type Amino Acid Transport With Non-Physiological Amino Acids In The Pahenu2 Mouse Model Of Phenylketonuria, Kara R. Vogel

Dissertations, Master's Theses and Master's Reports - Open

Phenylketonuria, an autosomal recessive Mendelian disorder, is one of the most common inborn errors of metabolism. Although currently treated by diet, many suboptimal outcomes occur for patients. Neuropathological outcomes include cognitive loss, white matter abnormalities, and hypo- or demyelination, resulting from high concentrations and/or fluctuating levels of phenylalanine. High phenylalanine can also result in competitive exclusion of other large neutral amino acids from the brain, including tyrosine and tryptophan (essential precursors of dopamine and serotonin). This competition occurs at the blood brain barrier, where the L-type amino acid transporter, LAT1, selectively facilitates entry of large neutral amino acids. The hypothesis …

Determinants Of Cns Adult Neurogenesis Are Sex, Hormones, Mouse Strain, Age, And Brain Region, Carrie Lynn Tatar

Wayne State University Dissertations

Multiple sclerosis is a sexually dimorphic (SD) disease that causes oligodendrocyte death but SD of glial cells is poorly studied. Here, we analyze SD of neural progenitors in 6-8wk and 6-8mo normal C57BL/6, SJL/J and BALB/c mice in the subventricular zone (SVZ), dorsolateral horn (DLC), corpus callosum (CC), and parenchyma. With a short 2 h BrdU pulse, no gender and strain differences are present at 6-8wk. At 6-8mo, the number of BrdU+ cells decreases 2-fold in both sexes, strains and regions indicating a common aging mechanism regulates BrdU incorporation. Strikingly, 2X more BrdU+ cells are found in all brain regions …

Understanding The Gender-Based Mechanism Of Mso In Als Mice: A Metabolic Characterization Of The Sod1-G93a Mouse Model, Monica Ann Bame

Wayne State University Dissertations

Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease characterized by motor neuron death and a corresponding loss of neuromuscular connections resulting in muscle atrophy. Patients become paralyzed shortly after symptom onset and typically die within one to five years of pulmonary complications. ALS is a relatively rare disease, with an overall incidence of approximately 2 in 100,000 people per year and a prevalence of about 5 in 100,000 people. It is typically associated with increasing age and has a slight male prevalence, with a male to female ratio of approximately 3:2. ALS is classified as either familial (the less …

Morphine And Clonidine Synergize To Ameliorate Low Back Pain In Mice, Maral Tajerian, Magali Millecamps, Laura S. Stone

Publications and Research

Chronic low back pain (LBP) is a debilitating condition associated with signs of axial and radiating pain. In humans with chronic LBP, opioids are often prescribed with varying outcomes and a multitude of side effects. Combination therapies, in which multiple pharmacological agents synergize to ameliorate pain without similar potentiation of adverse reactions, may be useful in improving therapeutic outcome in these patients. The SPARC-null mouse model of low back pain due to disc degeneration was used to assess the effects of opioid (morphine) andα2-adrenergic agonist (clonidine) coadministration on measures of axial and radiating pain. The results indicate that systemic morphine …

Adaptive Tolerance To Ocean Acidification In The Marine Sponge: Chondrilla Nucula, Sylvester Lee

Electronic Theses and Dissertations

The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has led to a 30% increase in ocean acidification over pre-industrial levels. Although most ocean acidification research thus far has focused on calcifying organisms such as corals, the potential of this increase in acidity (H+ ions) to cause acid-base imbalances in soft-bodied animals such as sponges has been grossly overlooked. Furthermore, many studies on ocean acidification have not considered the elevated temperatures that are predicted to accompany future climate change conditions. Sponges are crucial components to coral reef systems, providing food, nutrients, structure, and support. The sponge Chondrilla nucula …

Temporal Dynamics Of Galapagos Marine Iguna (Amblyhynchus Cristatus) Haulout, Brianna Gale Payne

Master's Theses

Galápagos marine iguanas (Amblyrhynchus cristatus) briefly forage in marine habitats but spend their remaining time hauled out on land. A wide range of diurnal activities, from social and thermoregulatory behaviors to sleep and food processing, occurs during haulout. To understand the dynamics of haulout and foraging in relation to environmental factors, I fit compartmental models derived from ordinary differential equations to field data collected daily from 30 April to 16 May 2011 at two sites—one Sandy and one Rocky—at Cabo Douglas, Isla Fernandina. The best model for haulout at the Sandy site accounts for 77–80% of observed variability and includes …

A Preliminary Study On The Potential Of Manuka Honey And Platelet-Rich Plasma In Wound Healing, Scott A. Sell, Patricia S. Wolfe, Andrew J. Spence, Isaac A. Rodriguez, Jennifer M. Mccoll, Rebecca L. Petrella, Koyal Garg, Jeffery J. Ericksen, Gary L. Bowlin

Ellmer School of Nursing Faculty Publications

Aim. The purpose of this study was to determine the in vitro response of cells critical to the wound healing process in culture media supplemented with a lyophilized preparation rich in growth factors (PRGF) and Manuka honey. Materials and Methods. This study utilized cell culture media supplemented with PRGF, as well as whole Manuka honey and the medical-grade Medihoney (MH), a Manuka honey product. The response of human fibroblasts (hDF), macrophages, and endothelial cells (hPMEC) was evaluated, with respect to cell proliferation, chemotaxis, collagen matrix production, and angiogenic potential, when subjected to culture with media containing PRGF, MH, Manuka honey, …

Annual Variation In Timing, Orientation And Effects Of Weather On Jefferson Salamander (Ambystoma Jeffersonianum) And Spotted Salamander (Ambystoma Maculatum) Movements In Central Kentucky, Christopher James St. Andre

Online Theses and Dissertations

Annual variation in temporal and spatial patterns of amphibian migration and dispersal are poorly understood. To address this issue, a circular drift fence was installed around an ephemeral pond at the Central Kentucky Wildlife Management Area, Madison County, Kentucky. The pond was checked daily for salamander movements from 17 January 2010 to 26 September 2010 and from 26 January 2011 to 3 August 2011, which corresponded to the activity season. Weather variables examined in relation to amphibian movements included barometric pressure, cumulative precipitation, temperature and relative humidity. Several species used the ephemeral pond during the study but few successfully reproduced. …

Effect Of Predator Type, Season, Brood Size, And West Nile Virus Infection On The Nest Defense Behavior Of Male And Female Eastern Bluebirds, Kayde Lynn Gilbert

Online Theses and Dissertations

The intensity of nest defense by birds can be influenced by many factors, including a parent's sex, brood size, stage of breeding season, type of predator, and physical condition. Because previous studies have produced conflicting results concerning the effects of these factors on the nest defense behavior of birds, additional studies are needed to better clarify how and why such factors influence behavior. No one to date has examined the possible effect of a viral infection on avian nest defense behavior. Thus, my objectives were to determine the effect of adult sex, brood size, stage of the breeding season, predator …

Society, Demography And Genetic Structure In The Spotted Hyena, Heather E. Watts

Biology Faculty Works

Spotted hyenas (Crocuta crocuta) are large mammalian carnivores, but their societies, called 'clans', resemble those of such cercopithecine primates as baboons and macaques with respect to their size, hierarchical structure, and frequency of social interaction among both kin and unrelated group-mates. However, in contrast to cercopithecine primates, spotted hyenas regularly hunt antelope and compete with group-mates for access to kills, which are extremely rich food sources, but also rare and ephemeral. This unique occurrence of baboon-like sociality among top-level predators has favoured the evolution of many unusual traits in this species. We briefly review the relevant socio-ecology of spotted hyenas, …

The Role Of Plant-Soil Feedback In Exotic Plant Invasion: Soil Type, Biotic Or Abiotic Factors?, Kelly Dawn Schradin

Browse all Theses and Dissertations

Plants alter soil characteristics in many ways causing changes in their subsequent growth resulting in either positive or negative feedback on their own fitness. Plants in their native ranges typically experience negative feedback from natural enemies, while feedback is often positive in invaded ranges where they escape enemies, experience new beneficial mutualisms, or bring with them a novel biochemical weapon. I conducted a fully factorial greenhouse experiment to examine plant-soil feedback in the invasive shrub Lonicera maackii and whether or not positive feedback may contribute to its successful invasion in southern Ohio. I also investigated whether the sign and strength …

Expression Of Inflamatory Response Genes In Ferrets Challenged With H5n1 Avian Influenza Virus, Brock M. Miniard

Browse all Theses and Dissertations

Influenza A H5N1 has emerged as a potential to be the next pandemic influenza. Ferrets are a promising model of H5N1 infection because the disease progression is similar to that known in humans, however reagents to characterize infections in ferrets are few. We developed real-time PCR assays for the ferret cytokines IL-1β, IL-2, IL-4, IL-8, IL-12p40, TNF-α, IFN-α, IFN-β, IFN-γ, TGFB-β1, and TGFB-β2. Forty-eight ferrets were vaccinated with either one of three vaccine formulations (Vaccine 1, Vaccine 2, or Vaccine 3), or saline (0.9% NaCl), then challenged intranasally with a lethal dose of H5N1 strain A/Vietnam/1203/04. Cytokine assays were then …

House Dust Mite Induced Gene Expression And Cytokine Secretion By Human Dermal Fibroblasts, Jananie Rockwood

Browse all Theses and Dissertations

House dust mites are a group of mites that are commonly found in homes worldwide. The three most commonly found species of house dust mites in temperate environments in the United States are Dermatophagoides farinae, Dermatophagoides pteronyssinus and Euroglyphus maynei. House dust mite allergens are strongly associated with asthma, perennial rhinitis and atopic dermatitis. Whole dust mite extracts contain both allergen and non-allergen molecules that can influence cell functions in the skin, mucous membranes of the nose and eyes, and epithelial linings of the lungs. Extracts from the three different house dust mite species contain different molecules that induce different …

Trading Resistance For Vigor: A Potential Mechanism For Invasion By The Asian Grass Microstegium Vimineum, Matthew Dickinson

Browse all Theses and Dissertations

The Evolution of Increased Competitive Ability (EICA) hypothesis predicts that subsequent to introduction, non-native plants escape enemies and selection favors genotypes that invest more in growth and reproduction and less in resistance. Here, I evaluated if the invasive Asian grass Microstegium vimineum has developed decreased resistance in its introduced range of the eastern US, as predicted by the EICA hypothesis. Asian and US genotypes were evaluated for differences in enemy damage, leaf toughness, specific leaf area (SLA), and flowering in a common garden experiment. Leaf damage, SLA, and flower production were greater and leaf toughness lower in US plants. These …