Biology Commons^™

Assortative Fertilization In The Elegans-Group Of Caenorhabditis, Sara Rose Seibert

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Assortative fertilization refers to the species-specific interactions between sperm and oocytes that affect the success of fertilization. One type of interaction is chemotaxis of sperm to oocytes. In Caenorhabditis elegans, amoeboid sperm must crawl along the uterine lining towards the spermathecae in response to oocyte-derived prostaglandin signals for fertilization. This chemotactic signaling system likely operates in other species of the Elegans-Group of Caenorhabditis as sperm of C. briggsae and C. remanei do localize to the C. elegans spermathecae. In this project the impacts of species-specific chemotaxis on fertilization and female fecundity were assessed. To accomplish this, the localization of …

Direct And Indirect Effects Of White-Tailed Deer (Odocoileus Virginianus) Herbivory On Beetle And Spider Assemblages In Northern Wisconsin, Elizabeth J. Sancomb

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White-tailed deer directly impact vegetation structure and species composition through selective foraging, and indirectly impact other species by altering habitat, food-web interactions, and microclimate. I examined the direct effects of deer exclusion on vegetation communities, and indirect effects on beetle, spider, and web-building spider (WBS) assemblages. Forb and woody plant percent cover were higher in exclosures, while graminoid cover was higher in controls. There were no differences in beetle and spider assemblages between browsed and protected areas. The absence of differences could be attributed to legacy effects, or alternatively high vagility of individuals. WBS assemblages were more abundant and diverse …

Effects Of Rev Protein On Microtubule Arrays In Living Cells, Nayana M. Nikumbh

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The HIV protein Rev regulates the expression of essential viral proteins during the course of infection by a mechanism that is well understood. It promotes nuclear export of viral transcripts, normally retained in the nucleus owing to the presence of introns, by interacting with host cell transport factors. However, over-expression of Rev in cells leads to defects in cell cycle progression, specifically slowing growth and impairing progression through mitosis (43). While it is possible that Rev may be altering the proteins in transport pathways, cell cycle defects may be attributed to Rev's interactions with other proteins.

In vitro experiments show …

Sexual Harassment And Feeding Inhibition Between Two Invasive Dengue Vectors, John Soghigian, Kathryn Gibbs, Ashleigh Stanton, Rachel Kaiser, Todd Livdahl

Biology

Two invasive mosquitoes, Aedes aegypti and Aedes albopictus, have been interacting during the course of a rapid range expansion by A. albopictus. We investigated the potential for interspecific feeding interference by male mosquitoes interacting with females within and between these species. A. aegypti feeding on both sugar and blood was suppressed when females of this species were exposed to A. albopictus males, but no change was observed when exposed to conspecifics. A. albopictus feeding was not affected by males of either species. The potential consequences of these behaviors are discussed within the context of other known interspecific effects, all of …

Effects Of Toxic Cyanobacteria (Microcystis Aeruginosa) On The Feeding And Reproduction Ecology Of The Copepod Eurytemora Affinis From Green Bay, Lake Michigan, Nicholas J. Barrett

Lawrence University Honors Projects

Toxic Cyanobacteria is known to be a bad food source to consumers as well as a main contributor to harmful algal blooms. This study investigates the feeding relationship between an invasive copepod in the Great Lakes system, Eurytemora affinis, and a toxic strain of cyanobacteria, Microcystis aeruginosa. E.affinis has been shown to feed on toxic cyanobacteria. By measuring the filtering rate, ingestion rate, egg production and offspring size between three different food conditions, we hope to gain insight into the effects of toxic cyanobacteria on the feeding and reproduction of this copepod. Food sources include a good green algal …

Genotyping-By-Sequencing For Populus Population Genomics: An Assessment Of Genome Sampling Patterns And Filtering Approaches, M. Schilling, Paul G. Wolf, A. M. Duffy, H. S. Rai, C. A. Rowe, B. A. Richardson, K. E. Mock

Biology Faculty Publications

Continuing advances in nucleotide sequencing technology are inspiring a suite of genomic approaches in studies of natural populations. Researchers are faced with data management and analytical scales that are increasing by orders of magnitude. With such dramatic advances comes a need to understand biases and error rates, which can be propagated and magnified in large-scale data acquisition and processing. Here we assess genomic sampling biases and the effects of various population-level data filtering strategies in a genotyping-by-sequencing (GBS) protocol. We focus on data from two species of Populus, because this genus has a relatively small genome and is emerging …

Mouse Oocyte Maturation And Embryo Development After Exposure To Vemurafenib (Plx4032), An Anti-Melanoma B-Raf V600e Inhibitor, Bo Liu

Theses and Dissertations in Biomedical Sciences

Vemurafenib is a selective B-Raf^V600E inhibitor in melanoma targeted therapy which also inhibits the wild type B- and C-Raf. In oocyte maturation, the C-Raf/MAPK pathway acts as an important self-enhancing and promoting system, w hereas in embryo development, the C-Raf/M APK pathway participates in pre- and post- implantation embryo proliferation and differentiation.

The hypothesis: Vemurafenib has detrimental effects on oocyte maturation and/or embryo development. Mouse oocytes and one cell (1C) mouse embryos were tested by ex vivo culturing with Vemurafenib in serial dilution. Oocytes were evaluated by cell cycle morphology, spindle formation and chromosomal alignment by im munofluorescence (IF) …

Production Of Destruxins From Metarhizium Spp. Fungi In Artificial Medium And In Endophytically Colonized Cowpea Plants, P. S. Golo, D. R. Gardner, Michelle M. Grilley, Jon Y. Takemoto, S. B. Krasnoff, M. S. Pires, E. K. K. Férnandes, V. R. Bittencourt, Donald W. Roberts

Biology Faculty Publications

Destruxins (DTXs) are cyclic depsipeptides produced by many Metarhizium isolates that have long been assumed to contribute to virulence of these entomopathogenic fungi. We evaluated the virulence of 20 Metarhizium isolates against insect larvae and measured the concentration of DTXs A, B, and E produced by these same isolates in submerged (shaken) cultures. Eight of the isolates (ARSEF 324, 724, 760, 1448, 1882, 1883, 3479, and 3918) did not produce DTXs A, B, or E during the five days of submerged culture. DTXs were first detected in culture medium at 2–3 days in submerged culture. Galleria mellonella and Tenebrio molitor …

Targeted Knockout Of Beclin-1 Reveals An Essential Function In Ovary And Testis, Thomas R. Gawriluk

Theses and Dissertations--Biology

An estimated 12% of couples worldwide are infertile. The contributing factor is approximately equal between men and women with nearly 25% diagnosed as idiopathic. Despite the increasing numbers of couples seeking assistance from infertility clinics, few molecular mechanisms have been identified for treatment. Autophagy is an evolutionarily conserved cellular process for bulk degradation and recycling of cytosolic components through the lysosome to maintain homeostasis. Several studies have observed increased levels of autophagy during ovarian folliculogenesis and gonadal steroidogenesis; however, no genetic studies to determine the significance of autophagy exist.

To investigate the function of autophagy in the ovary and testis, …

Dopaminergic And Activity-Dependent Modulation Of Mechanosensory Responses In Drosophila Melanogaster Larvae, Josh S. Titlow

Theses and Dissertations--Biology

A central theme of this dissertation is nervous system plasticity. Activity-dependent plasticity and dopaminergic modulation are two processes by which neural circuits adapt their function to developmental and environmental changes. These processes are involved in basic cognitive functions and can contribute to neurological disorder. An important goal in modern neurobiology is understanding how genotypic variation influences plasticity, and leveraging the quantitative genetics resources in model organisms is a valuable component of this endeavor. To this end I investigated activity-dependent plasticity and dopaminergic modulation in Drosophila melanogaster larvae using neurobiological and genetic approaches.

Larval mechanosensory behavior is described in Chapter 2. …

Small Rna Expression During Programmed Rearragement Of A Vertebrate Genome, Joseph R. Herdy Iii

Theses and Dissertations--Biology

The sea lamprey (Petromyzon marinus) undergoes programmed genome rearrangements (PGRs) during embryogenesis that results in the deletion of ~0.5 Gb of germline DNA from the somatic lineage. The underlying mechanism of these rearrangements remains largely unknown. miRNAs (microRNAs) and piRNAs (PIWI interacting RNAs) are two classes of small noncoding RNAs that play important roles in early vertebrate development, including differentiation of cell lineages, modulation of signaling pathways, and clearing of maternal transcripts. Here, I utilized next generation sequencing to determine the temporal expression of miRNAs, piRNAs, and other small noncoding RNAs during the first five days of lamprey …

Modular Network Construction Using Eqtl Data: An Analysis Of Computational Costs And Benefits, Yen Yi Ho, Leslie M. Cope, Giovanni Parmigiani

Faculty Publications

Background: In this paper, we consider analytic methods for the integrated analysis of genomic DNA variation and mRNA expression (also named as eQTL data), to discover genetic networks that are associated with a complex trait of interest. Our focus is the systematic evaluation of the trade-off between network size and network search efficiency in the construction of these networks. Results: We developed a modular approach to network construction, building from smaller networks to larger ones, thereby reducing the search space while including more variables in the analysis. The goal is achieving a lower computational cost while maintaining high confidence in …

Opiliones Biodiversity In Cusuco National Park, Honduras, Brittany N. Damron

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Biodiversity in the tropics is especially diverse and describing species found in the tropics is important. Opiliones species richness is higher in the tropics than the temperate zone, with diversity highest in low latitudes. This study aims to catalog the Opiliones community in Cusuco National Park, Honduras, while estimating species richness and describing their abundance, distribution and community structure. Fifty hours of sampling at 6 sites yielded 18 morphospecies and 264 individual Opiliones were collected. This study added one new described species to the Opiliones fauna of Honduras, and fourteen morphospecies may represent new species. An estimated 43 to 112 …

On The Helminth Fauna Of Small Mammals In Hustai National Park, Mongolia, Sumiya Ganzorig, Nyamsuren Batsaikhan, Katsuro Hagiwara, Scott Lyell Gardner, Kenji Baba, Buho Hoshino

Scott L. Gardner Publications

Introduction

The Hustai National Park is one of the special protected areas in Mongolia. The park is famous by the successful re-introduction of the wild horse (takhi), and its well-managed protection work. The park has a rich and diverse mammal fauna and flora. Of these, the takhi, and other large mammal species are objects of intensive research by the international researchers, but the parasitic helminth fauna in Hustai National Park is remained unknown. Species diversity of wildlife and its abundance, especially high density of both the prey and predators, might allow the presence of various parasitic and symbiotic organisms on …

Genome-Wide Gene Expression Effects Of Sex Chromosome Imprinting In Drosophila, Bernardo Lemos, Alan T. Branco, Pan-Pan Jiang, Daniel L. Hartl, Colin D. Meiklejohn

School of Biological Sciences: Faculty Publications

Imprinting is well-documented in both plant and animal species. In Drosophila, the Y chromosome is differently modified when transmitted through the male and female germlines. Here, we report genome-wide gene expression effects resulting from reversed parent-of-origin of the X and Y chromosomes. We found that hundreds of genes are differentially expressed between adult male Drosophila melanogaster that differ in the maternal and paternal origin of the sex chromosomes. Many of the differentially regulated genes are expressed specifically in testis and midgut cells, suggesting that sex chromosome imprinting might globally impact gene expression in these tissues. In contrast, we observed much …

Atx1/Atcompass And The H3k4me3 Marks: How Do They Activate Arabidopsis Genes?, Michael E. Fromm, Zoya Avramova

School of Biological Sciences: Faculty Publications

Despite the proven correlation between gene transcriptional activity and the levels of tri-methyl marks on histone 3 lysine4 (H3K4me3) of their nucleosomes, whether H3K4me3 contributes to, or “registers,” activated transcription is still controversial. Other questions of broad relevance are whether histone-modifying proteins are involved in the recruitment of Pol II and the general transcription machinery and whether they have roles other than their enzyme activities. We address these questions as well as the roles of the ARABIDOPSIS HOMOLOG OF TRITHORAX1 (ATX1), of the COMPASS-related (AtCOMPASS) protein complex, and of their product, H3K4me3, at ATX1-dependent genes. We suggest that the ambiguity …

Endogenous Aba Extraction And Measurement From Arabidopsis Leaves, Ning Liu, Yong Ding, Michael Fromm, Zoya Avramova

School of Biological Sciences: Faculty Publications

The endogenous messenger, the phytohormone abscisic acid (ABA) plays a major role in plant’s adaption to drought, salinity, cold and other abiotic stresses. In addition to abiotic stress signaling, ABA is involved also in developmental regulation and in responses to diverse biotic stresses. Dehydration stress results in a strong increase in endogenous ABA levels, which can be perceived by RCAR/PYR1/PYL receptors, initiating the ABA signaling pathway to coordinate the genome-wide gene expression, and plants adaptive physiological responses. ABA biosynthesis triggered by environmental cues as well as developmental signals occurs predominantly in vascular parenchyma cells. The measurement of ABA content in …

Aba Signaling Is Necessary But Not Sufficient For Rd29b Transcriptional Memory During Successive Dehydration Stresses In Arabidopsis Thaliana, Laetitia Virlouvet, Yong Ding, Hiroaki Fujii, Zoya Avramova, Michael Fromm

School of Biological Sciences: Faculty Publications

Plants subjected to a prior dehydration stress were seen to have altered transcriptional responses during a subsequent dehydration stress for up to 5 days after the initial stress. The abscisic acid (ABA) inducible RD29B gene of Arabidopsis thaliana was strongly induced after the first stress and displayed transcriptional memory with transcript levels nine-fold higher during the second dehydration stress. These increased transcript levels were due to an increased rate of transcription and are associated with an altered chromatin template during the recovery interval between the dehydration stresses. Here we use a combination of promoter deletion/substitutions, mutants in the trans-acting …

An Assembly Of Proteins And Lipid Domains Regulates Transport Of Phosphatidylserine To Phosphatidylserine Decarboxylase 2 In Saccharomyces Cerevisiae, Wayne R. Riekhof, Wen-I Wu, Jennifer L. Jones, Mrinalini Nikrad, Mallory M. Chan, Christopher J. R. Loewen, Dennis R. Voelker

School of Biological Sciences: Faculty Publications

Background: The machinery for interorganelle phosphatidylserine (PtdSer) transport is poorly defined at the molecular level.

Results: Molecular interaction studies identify specific protein-protein and protein-lipid interactions in PtdSer transport.

Conclusion: A protein and lipid interaction network defines key participants in PS transport to the locus of PtdSer-decarboxylase 2.

Significance: This study identifies important molecular participants involved in non-vesicular phospholipid traffic.

Detection Of Predator Cues Alters Mating Tactics In Male Wolf Spiders, Dustin J. Wilgers, Daniel Wickwire, Eileen Hebets

Eileen Hebets Publications

Males of the wolf spider, Rabidosa punctulata, exhibit condition-dependent alternative mating tactics, whereby small, poor condition males engage in multimodal courtship while large, good condition males adopt a direct mount tactic that forgoes courtship. This study explores the possibility that tactic-specific costs can help explain this unintuitive pattern of mating tactic expression. Specifically, we hypothesize that courtship signaling is costly with respect to eavesdropping by predators and that males can alter their tactic expression based upon the perceived environmental predation risk. We test this by first examining the risk of predation associated with different mating tactics. We use a …

The Roles Of Cis- And Trans-Regulation In The Evolution Of Regulatory Incompatibilities And Sexually Dimorphic Gene Expression, Colin D. Meiklejohn, Joseph D. Coolon, Daniel L. Hartl, Patricia J. Wittkopp

School of Biological Sciences: Faculty Publications

Evolutionary changes in gene expression underlie many aspects of phenotypic diversity within and among species. Understanding the genetic basis for evolved changes in gene expression is therefore an important component of a comprehensive understanding of the genetic basis of phenotypic evolution. Using interspecific introgression hybrids, we examined the genetic basis for divergence in genome-wide patterns of gene expression between Drosophila simulans and Drosophila mauritiana. We find that cis-regulatory and trans-regulatory divergences differ significantly in patterns of genetic architecture and evolution. The effects of cis-regulatory divergence are approximately additive in heterozygotes, quantitatively different between males and females, …

In Memoriam: Robert Lloyd Rausch—A Life In Nature And Field Biology, 1921–2012, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

During his distinguished career, Robert Rausch, a man of great integrity and principles, served in his lifetime as a singular ambassador for parasitology in a broad international arena. Robert was a friend to many, was honored to be considered an equal among the nomadic bands of Nunamiut traversing the Brooks Range 60 years ago, and will be long remembered for the strength of his science and his perceptive views of the natural world.

Integrating Evolutionary And Functional Tests Of Adaptive Hypotheses: A Case Study Of Altitudinal Differentiation In Hemoglobin Function In An Andean Sparrow, Zonotrichia Capensis, Zachary A. Cheviron, Chandrasekhar Natarajan, Joana Projecto-Garcia, Douglas K. Eddy, Jennifer Jones, Matthew D. Carling, Christopher C. Witt, Hideaki Moriyama, Roy E. Weber, Angela Fago, Jay F. Storz

School of Biological Sciences: Faculty Publications

In air-breathing vertebrates, the physiologically optimal blood-O_² affinity is jointly determined by the prevailing partial pressure of atmospheric O₂, the efficacy of pulmonary O₂ transfer, and internal metabolic demands. Consequently, genetic variation in the oxygenation properties of hemoglobin (Hb) may be subject to spatially varying selection in species with broad elevational distributions. Here we report the results of a combined functional and evolutionary analysis of Hb polymorphism in the rufouscollared sparrow (Zonotrichia capensis), a species that is continuously distributed across a steep elevational gradient on the Pacific slope of the Peruvian Andes. We integrated …

Multiplexing With Three-Primer Pcr For Rapid And Economical Microsatellite Validation, Salla Vartia, Patrick C. Collins, Thomas F. Cross, Richard D. Fitzgerald, David T. Gauthier, Philip Mcginnity, Luca Mirimin, Jens Carlsson

Biological Sciences Faculty Publications

The next generation sequencing revolution has enabled rapid discovery of genetic markers, however, development of fully functioning new markers still requires a long and costly process of marker validation. This study reports a rapid and economical approach for the validation and deployment of polymorphic microsatellite markers obtained from a 454 pyrosequencing library of Atlantic cod, Gadus morhua, Linnaeus 1758. Primers were designed from raw reads to amplify specific amplicon size ranges, allowing effective PCR multiplexing. Multiplexing was combined with a three-primer PCR approach using four universal tails to label amplicons with separate fluorochromes. A total of 192 primer pairs …

Quantitative Factors Proposed To Influence The Prevalence Of Canine Tick-Bourne Disease Agents In The United States, Roger W. Stich, Byron L. Blagburn, Dwight D. Bowman, Christopher Carpenter, M. Roberto Cortinas, Sidney A. Ewing, Desmond Foley, Holly Gaff, Graham J. Hickling, R. Ryan Lash

Biological Sciences Faculty Publications

The Companion Animal Parasite Council hosted a meeting to identify quantifiable factors that can influence the prevalence of tick-borne disease agents among dogs in North America. This report summarizes the approach used and the factors identified for further analysis with mathematical models of canine exposure to tick-borne pathogens.

The Performance Of Simple Artificial Floating Wetland Communities And Their Effects On Aquatic Nutrient Levels And Algal Abundance, Bradley L. Sleeth

UNF Graduate Theses and Dissertations

Harmful algal blooms are exponential increases in autotrophic microorganisms that proliferate in such a way that the surrounding environment, the local economy and the health of regional populations are negatively affected. Among the causes of these blooms are anthropogenic inputs of excess nitrogen and phosphorus into the environment through overfertilization. Floating treatment wetlands (FTW) have emerged as a novel method of reducing the negative impacts of these nutrient inputs by using artificial rafts to float normally emergent wetland plants on the surface of water bodies to assimilate excess nutrients. Because their use is so new, only limited research has been …

Water Column Ammonium Concentration And Salinity Influence Nitrogen Uptake And Growth Of Spartina Alterniflora, Rachel Mactavish

College of Graduate Studies: Theses & Dissertations

Salt marsh macrophytes, such as Spartina alterniflora, play a critical role in uptake and transformation of inorganic nitrogen before it reaches coastal waters, thereby reducing the potential for eutrophication. Although nitrogen availability typically limits S. alterniflora growth, it may be possible to exceed the nitrogen uptake capacity of S. alterniflora. Increasing either nitrogen concentrations or salinity are key factors regulating S. alterniflora nitrogen uptake. Investigating the effects of nutrients and salinity on S. alterniflora is important given that increases in inorganic nitrogen supply to surface waters from agriculture and urbanization occur simultaneously with freshwater withdrawals that reduce flow and increase …

The Effects Of Herbicide On The Endangered Herb Baptisia Arachnifera And Preliminary Nutrient Survey Of Leaf Tissue And Soil, Ruth Ann C. Steinbrecher

College of Graduate Studies: Theses & Dissertations

Baptisia arachnifera (Hairy Rattleweed) is an endangered herbaceous legume that only occurs in Wayne and Brantley Counties of Georgia, United States. Many of the remaining populations exist in areas now managed for timber. This study investigated the effects of Imazapyr, an herbicide commonly used in timber management, on health and vitality of B. arachnifera under both field and greenhouse conditions. This study also analyzed leaf and soil samples from six populations of B. arachnifera to determine the nutrient content of the leaves. A recensus of a B. arachnifera population was also conducted in a site without commercial timber management. In …

Effect Of Gamma Ray Irradiation And Cryopreservation On Pollen Stainability, In Vitro Germination, And Fruit Set In Citrus, Manoj Kundu, Anil Dubey, Manish Srivastav, Surendra Malik, Bhupinder Singh

Turkish Journal of Biology

The present work analyzed the stainability and in vitro germinability of the gamma-ray-irradiated fresh and cryopreserved pollens of 3 Citrus species: C. limon, C. limetta, and C. sinensis. Fruit set after pollinating 75 flowers of C. grandis with irradiated and nonirradiated (control) fresh and cryopreserved pollen was also assessed. Results showed that in solid and liquid culture media the highest in vitro germination values were detected in fresh (61.45% and 62.53%, respectively) as well as cryopreserved (53.17% and 55.36%, respectively) C. sinensis nonirradiated pollens. However, at a higher irradiation dose of 500 Gy in both culture media, the minimum reduction …

Ex Situ Conservation Of Dianthus Giganteus D’Urv. Subsp. Banaticus (Heuff.) Tutin By In Vitro Culture And Assessment Of Somaclonal Variability By Molecular Markers, Liliana Jarda, Anca Butiuc Keul, Maria Hohn, Andrzej Pedryc, Victoria Cristea

Turkish Journal of Biology

Ex situ conservation of Dianthus giganteus subsp. banaticus was obtained by in vitro culture on different culture media supplemented with phytohormones. Assessment of somaclonal variability over a period of preservation by in vitro culture is required prior to introduction and acclimatization in natural habitats. In this study we used 2 types of molecular markers, ISSR and multilocus SSR markers, which allow comparison of different alleles, to assess the somaclonal variability of endemic taxa Dianthus giganteus subsp. banaticus after a period of 24 months of preservation by in vitro culture. The assessment of somaclonal variability of D. giganteus subsp. banaticus shows …