Biology Commons^™

Exogenous Expression Of Human Na, K-Atpase Isoforms In Insect Cells, Christal Renee' Carpenter

McCabe Thesis Collection

The Na-K-ATPase or Na pump is a membrane bound enzyme that maintains a high concentration of K+ and low concentration of Na+ in most animal cells. Three subunits constitute the Na pump, named alpha (ex), beta (~). and gamma (y). The ex subunit is responsible for the catalytic and transport of the enzyme, the ~ subunit is important for bringing the ex to the plasma membrane of the cell, and y is a regulatory subunit of the Na pump. In addition, there are several molecular variants or isoforms of the ex and ~ subunits. At present four different ex (ex …

Low Leaf N And P Resorption Contributes To Nutrient Limitation In Two Desert Shrubs, Rebecca E. Drenovsky, J. H. Richards

Biology

Both water and nutrients are limiting in arid environments, and desert plants have adapted to these limitations through numerous developmental and physiological mechanisms. In the Mono Basin, California, USA, co-dominant Sarcobatus vermiculatus and Chrysothamnus nauseosus ssp. consimilis are differentially N and P limited. We hypothesized that low leaf N resorption contributes to N-limitation in Sarcobatus and that low leaf P resorption contributes to P-limitation in Chrysothamnus. As predicted, Sarcobatus resorbed proportionally 1.7-fold less N than Chrysothamnus, but reduced leaf P in senescent leaves to lower levels than Chrysothamnus (8.0–10.8-fold lower based on leaf area or mass, respectively), consistent with N, …

The Effects Of Carotenoid And Food Intake On Caudal Fin Regeneration In Male Guppies, Gita R. Kolluru, N. C. Ruiz, N. Del Cid, Eric Dunlop, Gregory F. Grether

Biological Sciences

The trade‐offs involved in allocating carotenoid pigments and food to healing and regrowing damaged caudal fin tissue v. other functions were examined in guppies Poecilia reticulata, a species in which females prefer males that display larger amounts of carotenoids in their skin. The guppies were derived from four natural populations in Trinidad that differed in resource availability but not predation intensity. Carotenoids, food and site of origin did not affect either absolute or relative fin regrowth, which suggested that fin regeneration in guppies was not constrained by carotenoid availability. It is possible that carotenoid intake influences fin regeneration in …

Expression Profiling And Local Adaptation Of Boechera Holboellii Populations For Water Use Efficiency Across A Naturally Occurring Water Stress Gradient, Charles A. Knight, Heiko Vogel, Juergen Kroymann, Alice Shumate, Hanneke Witsenboer, Thomas Mitchell-Olds

Biological Sciences

We studied the physiological basis of local adaptation to drought in Boechera holboellii, a perennial relative of Arabidopsis thaliana, and used cDNA–AFLPs to identify candidate genes showing differential expression in these populations. We compared two populations of B. holboellii from contrasting water environments in a reciprocal transplant experiment, as well as in a laboratory dry-down experiment. We continuously measured the water content of soils using time domain reflectometery (TDR). We compared populations for their water use efficiency (WUE), root/shoot ratios (R:S) and leaf mass per unit area (LMA) in the field and in the laboratory, and identified candidate …

Comparative Genomic Analyses And Expression Of A Set Of Overlapping Open Reading Frames Of Frog Virus 3, Type Species Of Ranavirus (Family Iridoviridae), Wendy Guat Hoon Tan

Dissertations

Frog virus 3 (FV3) is the type species member of the genus Ranavirus (family Iridoviridae ). To better understand the molecular mechanisms involved in the replication of FV3, including transcription of its highly methylated DNA genome, the complete nucleotide sequence of the FV3 genome has been determined. The FV3 genome is 105, 903 base pairs long excluding the terminal redundancy. The G+C content of FV3 genome is 55% and it encodes 98 non-overlappingpotential open reading frames (ORFs) containing 50 to 1293 amino acids. Eighty-four ORFs have significant homology to known proteins of other iridoviruses, whereas 14 are unique FV3 ORFs. …

Comparison Of The Ingestion And Digestion Rates Of Ochromonas Danica Grazing On Pseudomonas Fluorescens Of Varying Food Quality, Stephen Paul Shannon

Biology Dissertations - Archive

Flagellate prey selection appears to depend on morphological characteristics of prey such as cell size and motility, as well as on physiochemical characteristics such as digestibility and cell surface characteristics. Pseudomonas fluorescens was grown in chemostats at four dilution rates (0.03, 0.06, 0.10, 0.13 h-1) and three temperatures (14, 20, 28°C) to produce cells of varying morphological characteristics (cell size) and physiochemical characteristics or food quality (as determined by the C:N:P ratio). Heat-killed bacteria of a given food quality were prepared and used to grow the flagellate Ochromonas danica. Ingestion and digestion rates were determined using fluorescently labeled bacteria of …

Age And Population Structure Of Joshua Trees (Yucca Brevifolia) In The Northwestern Mojave Desert, Kimberly D. Gilliland, Nancy J. Huntly, J. E. Anderson

Biology Faculty Publications

Many desert perennials are long-lived, but there are few data on ages or population structures of desert plants. We used 2 methods to estimate ages of a population of Yucca brevifolia (Joshua tree) in southwestern Utah from a 14-year census of plant sizes. Plant height at the 1st census ranged from 0.08 m to 6.0 m, and trees grew in height at a mean rate of 3.75 cm ⋅ yr^–1. Plants also increased slowly in basal diameter (0.142 cm ⋅ yr^–1) and branch length (0.024 m ⋅ yr^–1), but basal diameter varied greatly from …

The Origin Of Bubonic Plague, Alan L. Gillen, Frank Sherwin

Faculty Publications and Presentations

Although some forms of the bacterium Yersinia are harmless, other forms have devastated human populations, causing a plague of biblical proportions (Psalm 91:3-7, Psalm 91:9-10,). Bubonic plague, also known as the ‘Black Death’ that killed one fourth of Europe’s population in the 1300s, appeared as a great pestilence several times in the Old Testament, including in Psalm 91 and in 2 Samuel 24:14-25. Perhaps the clearest example of such a plague is recorded in 1 Samuel 6:4-19, where there is a specific reference to the tumors on people (bubos = the tumors of lymph glands) …

The Contradictory Definitions Of Heterochromatin: Transcription And Silencing, Kathryn Huisinga, Brent Brower-Toland, Sarah C.R. Elgin

Biology Faculty Research

Eukaryotic genomes are packaged in two general varieties of chromatin: gene-rich euchromatin and gene-poor heterochromatin. Each type of chromatin has been defined by the presence of distinct chromosomal proteins and posttranslational histone modifications. This review addresses recent findings that appear to blur the definitions of euchromatin and heterochromatin by pointing to the presence of typically heterochromatic modifications (including H3K9me) in euchromatin and typically euchromatic enzymes (including RNA polymerases) in heterochromatin. We discuss the implications of these new findings for the current definition of heterochromatin.

Predicting Distribution, Habitat Suitability And The Potential Loss Of Habitat For Sitta Formosa, The Beautiful Nuthatch, Jill C. Witt

Masters Theses

The beautiful nuthatch, Sitta formosa, occurs in high-altitude evergreen and semi-evergreen forests throughout the south and southeastern extent of the Himalayan Mountains. Populations of S. formosa are small, declining and severely fragmented as a result of habitat degradation and fragmentation, and therefore it is considered vulnerable by the World Conservation Union and is included in the 2004 Red List of Threatened Species. I used ecological niche factor analysis to model the potential distribution and predict suitable habitat for S. formosa. By using 59 presence locations, collected from museum specimens and biodiversity surveys, and together with topographic and …

Olfactory Bulb Neurons Of Adult Zebrafish Morphology, Distribution, Cellular Interactions And Structural Stability Following Deafferentation, Cynthia L. Fuller

Dissertations

The zebrafish is becoming an increasingly popular model for studies involving olfactory function, yet there is still much to be learned about the anatomy and circuitry of different cell types in the olfactory bulb. This study focuses on identifying the morphology and distribution of output neurons and interneurons in the olfactory bulb of adult zebrafish, Danio rerio . Furthermore, this investigation examines the cellular interactions of the primary output neuron, the mitral cell, and addresses the issue of neuronal plasticity by considering the structural stability of this cell type following loss of afferent innervation.

Using retrograde tract tracing with various …

Effectiveness Of Cane Toad Eradication Methods: Arakwal National Park, Matthew Miller

Independent Study Project (ISP) Collection

The cane toad (Bufo marinus) is a pest throughout Australia. Not only is it poisonous to native predators, it also consumes or out competes native fauna. It has only recently entered into Northern New South Wales where the site for this study is located, at Arakwal National Park. This study aims to discover the most effective method of cane toad eradication in the National Park.

Over the course of 18 days, three traps were set and rotated between 9 different sites. Traps were set at sunset and cleared at sunrise. The three traps used were; (1) Pitfall style trap by …

Time Constraints Mediate Predator-Induced Plasticity In Immune Function, Condition, And Life History, Robby Stoks, Marjan De Block, Stefanie Slos, Wendy Van Doorslaer, Jens Rolff

Dartmouth Scholarship

The simultaneous presence of predators and a limited time for development imposes a conflict: accelerating growth under time constraints comes at the cost of higher predation risk mediated by increased foraging. The few studies that have addressed this trade-off have dealt only with life history traits such as age and size at maturity. Physiological traits have largely been ignored in studies assessing the impact of environmental stressors, and it is largely unknown whether they respond independently of life history traits. Here, we studied the simultaneous effects of time constraints, i.e., as imposed by seasonality, and predation risk on immune defense, …

Thermal Stress On Intertidal Limpets: Long-Term Hindcasts And Lethal Limits, Mark Denny, Luke Miller, Christopher Harley

Faculty Publications, Biological Sciences

When coupled with long-term meteorological records, a heat-budget model for the limpet, Lottia gigantea, provides a wealth of information regarding environmental and topographic controls of body temperature in this ecologically important species. (1) The maximum body temperature predicted for any site (37.5°C) is insufficient to kill all limpets, suggesting that acute thermal stress does not set an absolute upper limit to the elevation of L. gigantea on the shore. Therefore, the upper limit must be set by behavioral responses, sublethal effects or ecological interactions. (2) Temperatures sufficient to kill limpets are reached at only a small fraction of substratum orientations …

Plasmid Probes For Screening Specific Genes In Large Fragment Dna Libraries, Leah Ferguson

Senior Honors Projects

Heliothis virescens, a member of the lepidopteran family, is of great importance to many people who rely on agriculture as a source of income because it is a pest of many important crops. Because H. virescens feeds on a broad array of hosts including cotton, tobacco, tomato, and soybean it has earned its place as a major nuisance in the United States. Heliothis subflexa is a close taxonomic relative of H. virescens, but the two species differ in that H. subflexa is a specialized herbivore that only feeds on plants in the genus Physalis. Studies have been performed to determine …

Survivor, Kala Pattar, Kathy Frees, Suzanne Donoval

Student Research

Conservation education is becoming increasingly important as the environment is in growing danger. As technology advances and humans become more concerned with convenience, conservation is getting moved to the back burner. It is important to encourage positive attitudes towards conservation issues, and one way to achieve this is through educating children about the environment and the consequences of our actions. We decided to conduct a field trip in which 6th grade students would have the opportunity to spend the day in the DePauw University Nature Park learning about environmental issues. This field trip is aimed at teaching the students about …

Automated Oxidase-Coupled Amperometric Microsensor With Integrated Electrochemical Actuation System For Continuous Sensing Of Saccharoids, Yadunandana Yellambalase, Jongwon Park, Chang-Soo Kim, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

Recent developments for biosensors have been mainly focused on miniaturization and exploratory use of new materials. It should be emphasized that the absence of a novel "in-situ self-calibration/diagnosis technique" that is not connected to an external apparatus is a key obstacle to the realization of a biosensor for continuous use with minimum attendance. To address this deficiency, a novel needle-type biosensor system with fully automated operations is being developed, in which a novel oxidase-coupled amperometric sensor with oxygen depleting/generating actuator is interfaced with an electrochemical instrument and a perfusion system. Labview virtual instrument has been also developed to oversee the …

The Dogma Of The 30 Meter Riparian Buffer: The Case Of The Boreal Toad (Bufo Boreas Boreas), Michael C. Goates

Theses and Dissertations

We tested the adequacy of standard 30 m riparian buffers for semi-aquatic vertebrate species, using the boreal toad (Bufo boreas boreas) as an example. We monitored toad populations in south-central Utah using radio telemetry during the summers of 2003 and 2004. We found 30 m buffers inadequate for protecting boreal toads and suggest this is likely true for other species as well. Managers must consider several factors when constructing buffers: (1) Buffer requirements may vary by time of year. While we located toads most often in wet habitats, toads commonly utilized upland habitats in late summer, occasionally at distances greater …

Ampk Regulation Of Mouse Oocyte Meiotic Resumption In Vitro, Jing Chen, Emma R. Hudson, Maggie M. Chi, Aimee S. Chang, Kelle H. Moley, D. Grahame Hardie, Stephen M. Downs

Biological Sciences Faculty Research and Publications

We have previously shown that the adenosine analog 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR), an activator of AMP-activated protein kinase (AMPK), stimulates an increase in AMPK activity and induces meiotic resumption in mouse oocytes [Downs, S.M., Hudson, E.R., Hardie, D.G., 2002. A potential role for AMP-activated protein kinase in meiotic induction in mouse oocytes. Dev. Biol, 245, 200–212]. The present study was carried out to better define a causative role for AMPK in oocyte meiotic maturation. When microinjected with a constitutively active AMPK, about 20% of mouse oocytes maintained in meiotic arrest with dibutyryl cAMP (dbcAMP) were stimulated to undergo germinal vesicle breakdown (GVB), …

Cytochrome P4501a Is Induced In Endothelial Cell Lines From The Kidney And Lung Of The Bottlenose Dolphin, Tursiops Truncatus, Rita Anne Garrick, Bruce R. Woodin, Joanna Y. Wilson, Bobby L. Middlebrooks, John J. Stegman

Faculty Publications

Marine mammals respond to the presence of polycyclic and planar halogenated aromatic hydrocarbons (PAH or PHAH) with the induced expression in endothelium of cytochrome P4501A1, regulated through the aryl hydrocarbon receptor (AHR) transcription factor. Physiological responses in other animals, such as edema and inflammation indicate that the endothelium may be compromised by exposure to AHR agonists, which are ubiquitous in the marine environment. In other mammals and fish the cellular and molecular consequences of exposure to AHR agonists have been elucidated in cultured endothelial cells. We have cultured and characterized cetacean endothelial cells (EC) and used them in induction studies. …

A Dual-Genome Microarray For The Pea Aphid, Acyrthosiphon Pisum, And Its Obligate Bacterial Symbiont, Buchnera Aphidicola, Alex C. C. Wilson, Helen E. Dunbar, Gregory K. Davis, Wayne B. Hunter, David L. Stern, Nancy A. Moran

Biology Articles and Papers

Background

The best studied insect-symbiont system is that of aphids and their primary bacterial endosymbiont Buchnera aphidicola. Buchnera inhabits specialized host cells called bacteriocytes, provides nutrients to the aphid and has co-speciated with its aphid hosts for the past 150 million years. We have used a single microarray to examine gene expression in the pea aphid, Acyrthosiphon pisum, and its resident Buchnera. Very little is known of gene expression in aphids, few studies have examined gene expression in Buchnera, and no study has examined simultaneously the expression profiles of a host and its symbiont. Expression profiling …

Luther Burbank: Honorary Member Of The American Breeders' Association, William D. Stansfield

Biological Sciences

No abstract provided.

Rapid Signaling At The Plasma Membrane By A Nuclear Receptor For Thyroid Hormone, Hemayet Ullah

Department of Biology Faculty Publications

Many nuclear hormones have physiological effects that are too rapid to be explained by changes in gene expression and are often attributed to unidentified or novel G protein-coupled receptors. Thyroid hormone is essential for normal human brain development, but the molecular mechanisms responsible for its effects remain to be identified. Here, we present direct molecular evidence for potassium channel stimulation in a rat pituitary cell line (GH(4)C(1)) by a nuclear receptor for thyroid hormone, TRbeta, acting rapidly at the plasma membrane through phosphatidylinositol 3-kinase (PI3K) to slow the deactivation of KCNH2 channels already in the membrane. Signaling was disrupted by …

A Hydrothermal After-Ripening Time Model For Seed Dormancy Loss In Bromus Tectorum L., Phil S. Allen, Necia B. Bair

Faculty Publications

After-ripening, the loss of dormancy under dry conditions, is associated with a decrease in mean base water potential for germination of Bromus tectorum L. seeds. After-ripening rate is a linear function of temperature above a base temperature, so that dormancy loss can be quantified using a thermal after-ripening time (TAR) model. To incorporate storage water potential into TAR, we created a hydrothermal after-ripening time (HTAR) model. Seeds from two B. tectorum populations were stored under controlled temperatures (20 or 30° C) and water potentials (400 to 40MPa). Subsamples were periodically removed from each storage treatment and incubated at 15 or …

Time For International Policies On Biological Invasions, Inderjit, Ragan M. Callaway, Shalini Kaushik

Biological Sciences Faculty Publications

No abstract provided.

Comparison Of The Barnacle, Balanus Amphitrite, In Different Environments, Katsura Mastuda

Loma Linda University Electronic Theses, Dissertations & Projects

The Salton Sea is a saline lake located centrally in the Colorado Desert, California. Salinity as well as nutrients of the Sea have been increasing since 1907, thus it is currently facing ecological collapse. The barnacle, Balanus amphitrite saltonensis at the Salton Sea was once thought to be a subspecies of B. amphitrite due to distinctive morphological differences between populations at the Sea and San Diego Bay. However, only one subspecies, Balanus amphitrite amphitrite, currently exists based on genetic studies. My study investigates physiological, survival, and morphological differences of B. amphitrite populations from the Salton Sea and San Diego …

Systematics Of The Endangered Mauremys Mutica And Mauremys Annamensis, Jonathan Julio Fong

Loma Linda University Electronic Theses, Dissertations & Projects

Almost all turtle species in Asia are going extinct due to the demand for turtle products as food and medicine. A difficulty in creating effective conservation measures is that very little is known about the evolutionary relationships between populations and species. It is believed that several lineages we are currently calling species could in actuality be a complex of several species. One of these supposed species is the Yellow Pond Turtle, Mauremys mutica. Previous research has shown this group to have a tremendous amount of morphological and molecular diversity. In this study, I have used a combination of known-locality, farm, …

Queen Weights Of Polygyne Solenopsis Invicta And S. Xyloni Suggest Reduced Competitive Ability, Ricardo A. Ramirez, D C. Thompson

Biology Faculty Publications

Solenopsis invicta Buren populations were confirmed in southern New Mexico, resulting in a quarantine of Doña Ana County in 1998; however, Solenopsis xyloni McCook remains the dominant fire ant. This study compared the queen weights and egg production of polygyne colonies of both species. There was no difference in live weights of the major worker caste; however, queens were very different in weight. In this study, S. invicta queens weighed almost twice as much as S. xyloni (S. invicta = 11.32 ± 0.25mg vs. S. xyloni = 6.40 ± 0.30mg) and produced over 50% as many eggs as S. xyloni. …

Cardiorespiratory Responses To Physical Work During And Following 17 Days Of Bed Rest And Spaceflight, Todd A. Trappe, Scott Trappe, Gary A. Lee, Jeffrey J. Widrick, Robert H. Fitts, David Costill

Biological Sciences Faculty Research and Publications

To determine the influence of a 17-day exposure to real and simulated spaceflight (SF) on cardiorespiratory function during exercise, four male crewmembers of the STS-78 space shuttle flight and eight male volunteers were studied before, during, and after the 17-day mission and 17 days of -6° head-down-tilt bed rest (BR), respectively. Measurements of oxygen uptake, pulmonary ventilation, and heart rate were made during submaximal cycling 60, 30, and 15 days before the SF liftoff and 12 and 7 days before BR; on SF days 2, 8, and 13 and on BR days 2, 8, and 13; and on days …

Nuclear Rna Surveillance In Saccharomyces Cerevisiae: Trf4p-Dependent Polyadenylation Of Nascent Hypomethylated Trna And An Aberrant Form Of 5s Rrna, Sujatha A. Kadaba, Xuying Wang, James T. Anderson

Biological Sciences Faculty Research and Publications

1-Methyladenosine modification at position 58 of tRNA is catalyzed by a two-subunit methyltransferase composed of Trm6p and Trm61p in Saccharomyces cerevisiae. Initiator tRNA (tRNA_i^Met) lacking m¹A58 (hypomethylated) is rendered unstable through the cooperative function of the poly(A) polymerases, Trf4p/Trf5p, and the nuclear exosome. We provide evidence that a catalytically active Trf4p poly(A) polymerase is required for polyadenylation of hypomethylated tRNA_i^Met in vivo. DNA sequence analysis of tRNA_i^Met cDNAs and Northern hybridizations of poly(A)+ RNA provide evidence that nascent pre-tRNA_i^Met transcripts are targeted for polyadenylation and degradation. We determined …