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Characterizing the Properties of Cell Volume Regulation in Retinal Neurons and Glia: A Role for the Mechanosensitive Cation Channel TRPV4

January 01, 2013 12:00 AM
Andrew Jo, University of Utah Ophthalmology and Visual Sciences All cells, including retinal neurons and glia, must sense and adapt to physical changes in their local environment (e.g. changes in osmotic pressure). Osmotic water flux can cause aberrant cell volume changes, which can contribute to tissue damage, edema, and neuronal hyperexcitability and excitotoxicity. We hypothesized that force-sensitive proteins enable retinal cells to monitor their physical form (e.g. volume) and help maintain homeostasis by regulating cell volume. To test this, we first investigated the properties of cell morphology when cells were bathed in solutions with different tonicities. Under these conditions, we measured changes in cell volume due to osmosis in retinal ganglion cells (RGCs) and Müller glia. We found RGCs were unable to actively adjust their volume, whereas Müller glia reduced their swollen volume in the continued presence of hypotonicity. The regulation of cellular volume often involves calcium signals. We tested whether calcium plays a role in the regulation of retinal cell volume. Free calcium within the cells was sequestered using cytosolic BAPTA, which decreased the extent of hypotonic swelling. This demonstrates that calcium elevations increase the extent of cell swelling. Because cell volume was dependent on calcium, which was elevated by membrane stretch, we hypothesized that the osmosensitive cation channel TRPV4 would transduce osmotic pressure and contribute to cell volume regulation. In an experiment using a selective TRPV4 inhibitor, the extent of hypotonic-induced swelling was reduced. Thus, the opening of TRPV4 leads to a calcium influx that exacerbated cellular swelling. In addition, we tested the idea that TRPV1 cation channel is involved in responses to osmotic stimuli. In an experiment using a selective TRPV1 antagonist, preliminary results show that the extent of hypotonic-induced swelling decreased. This signals that TRPV1 may have a role in volume regulation in retinal neurons and glia. Thus, inhibition of these force-sensitive protein channels might alleviate the deleterious effects of volume changes in pathological contexts. Our findings therefore have implications for our understanding of retinal mechanotransduction and osmoregulation as well as provide a mechanistic framework for developing new therapeutic strategies aimed at blinding conditions that involve mechanical stress and cellular morphology.

SNAP-25 Neurotransmission in C. elegans

January 01, 2013 12:00 AM
Viktor Jiracek, University of Utah Biology The nervous system is responsible for cognition, memory, and motor function. Neurons communicate with each other at intercellular connections called synapses. It is at these locations that vesicles fuse with the plasma membrane and release their contents into the space between the neurons (synaptic cleft). SNARE proteins (synaptobrevin, syntaxin and SNAP-25) facilitate synaptic vesicle fusion by winding together in a four-helix bundle forcing the mixture of opposing membranes. After exocytosis, the cell regenerates vesicles by a process called endocytosis. This process involves the budding of membrane back into the cytoplasm re-forming a functional synaptic vesicle. This progression from vesicle fusion to internalization is termed the “synaptic vesicle cycle” and is coordinated by a long list of molecular players. The SNARE proteins are classically considered to be unique to exocytosis. However, preliminary results from Erik Jorgensen’s lab have implicated SNAP-25 in endocytosis. Although we have evidence that SNAP-25 is required for endocytosis, the molecular mechanism is completely unknown. In this proposal we use forward genetics in the model organism C. elegans to identify novel protein interactions required for SNAP-25 mediated endocytosis. We have designed three suppressor screens that are predicted to target the role of SNAP-25 in exocytosis, endocytosis and general function. The first two screens use crippled forms of SNAP-25 (hypomorphs) while the last screen uses a deletion allele of the SNAP-25 gene (null mutation). With these screens we hope to precisely identify the molecular players involved in SNAP-25 mediated endocytosis versus exocytosis.

Does Gamma-Tocopherol Lower Blood Pressure in Diabetic Mice?

January 01, 2013 12:00 AM
Makenzie Hawkins, University of Utah Nutrition Cardiovascular disease (CVD) is the leading cause of death in the United States. Gamma-tocopherol (GTC) has been studied in its relation to hypertension and CVD. GTC has protective effects on the endothelium of arteries; the endothelium is in part responsible for regulating arterial relaxation and reducing blood pressure (BP). Diabetic mice (DB) were chosen for this study because of the associated co-morbidities of hypertension and excess body weight. Eight-week-old mice were divided into 3 separate groups: wild-type fed control (CON) diets (n=12), DB fed CON diets (n=12), and DB fed GTC supplemented diets (0.1%, n=12). BP was measured every week for 8 wk. Body weights were measured every wk and morphometric values were measured at the end of the 8-wk period. There was no statistically significant (P<0.05) difference in systolic and diastolic BP between DB-GTC and DB-CON. There was also no statistically significant (P<0.05) difference in heart rate between DB-GTC and DB-CON. After 8 wk, DB-GTC mice had lower (P<0.05) body weight versus the DB-CON group. In conclusion, a GTC supplemented diet did not result in a change in BP. However, GTC may have blunted weight gain and adipose tissue mass in DB-GTC compared to DB-CON. We speculate this may be due to a reduction of food consumption during the experimental period.

Dynamic Microtubules and Endomembrane Cycling Contribute to Polarity Establishment and Early Development of Ectocarpus Mitospores

January 01, 2013 12:00 AM
Diego Cordero, University of Utah Biology Many zygotes and spores of brown algae are photosensitive and establish a developmental axis in accordance with directional light cues. Ectocarpus siliculosus is being advanced as a genetic and genomic model organism for investigating brown alga development, and this report investigates photopolarization of the growth axis of mitospores. When exposed to unidirectional light, mitospores photopolarized and established a growth axis such that germination was preferentially localized to the shaded hemisphere of the spore body. The roles of the microtubule cytoskeleton and endomembrane cycling in the photopolarization process were investigated using pharmacological agents. Disruption of microtubule dynamics progressively reduced the percentage of mitospores that photopolarized, while inhibition of vesicle secretion blocked photopolarization nearly completely. Chronic treatment with these pharmacological agents severely affected algal morphogenesis. Microtubules in mitospores and algal filaments were imaged by confocal microscopy. Mitospores contained a radial microtubule array emanating from a centrosome associated with the nuclear envelope. At germination, the radial array gradually transitioned into a longitudinal array with microtubules extending into the emerging apex. At mitosis, spindles were aligned with the growth axis of cylindrical cells in the filament, and the division plane bisected the spindle axis. These studies demonstrate that dynamic membrane cycling and microtubule assembly play fundamental roles in photopolarization, and provide a foundation for future genetic and genomic investigations of this important developmental process.

Urbanization and its Effects on Prey Preference in Wandering Garter Snakes (Thamnophis elegans vagrant)

January 01, 2013 12:00 AM
Dillon Monroe, Southern Utah University Biology When an area is developed no part of that habitat is left unaffected. Urbanization creates many problems for animals by creating physical barriers, fragmenting habitat, introducing completely new habitat, and introducing species. Exotic species are often better competitors for resources and often competitively exclude native species, resulting in population declines and ecosystem disruption. Despite the negative effects of urbanization some species are able to adapt and survive in urban ecosystems. One such species is the wandering garter snake (Thamnophis elegans vagrans). This species is described as a generalist in habitat selection and is often seen in urban communities basking on sidewalks and pavement, living in gardens, and feeding on rodents, insects, and other species. One unique characteristic of this genus is that prey preference has been observed as being a genetic trait and possesses variation, and as such can be modified via natural selection. For my research project I looked at whether prey preference of T. elegans vagrans differs between snakes from three different locations with varying levels of human development. From these three locations in Utah, Tropic reservoir, Monroe (Sevier River), and Utah Lake, we obtained a total of 14 snakes and found that in this group of snakes there is no correlation of prey preference in snakes to level of development of the habitat.

Survey for Helenalin in Utah Asteraceae Species

January 01, 2013 12:00 AM
Taylor Nelson, Weber State University Botany Arnica is a common form of complementary medicine used to treat bruises and sore muscles. Most arnica preparations are made as an oil or gel by soaking the flowers of Arnica montana (a member of the Asteraceae) in an oil, such as olive oil, to extract helenalin, the presumed active component. Helenalin, a sesquiterpene lactone, has been shown to inhibit transcription factor NF-?B, a factor which controls the expression of dozens of genes involved in inflammation responses (Rungeler et al. 1999). Due to arnica’s popularity, A. montana is becoming scarce in Europe (its native range) and is sometimes substituted commercially with A. chamissonis (Cassells et al. 1999). Therefore, this study focused on finding other sources of helenalin among the Asteraceae. A. chamissonis, A. cordifolia, A. latifolia, A. longifolia, A. mollis and Helianthella uniflora were collected from Alta, UT, and Helenium autumnale from Salt Lake City, UT, at elevations of approximately 10,500 feet and 4,200 feet, respectively. Sesquiterpenes were extracted from the flowers by dipping them in methylene chloride and separated by thin-layer chromatography. Helenalin and possible helenalin derivatives were identified by their reaction with vanillin and comparison to a pure helenalin standard. Flowers from all seven of the species contained helenalin, with Helenium autumnale containing the highest concentration and A. latifolia the lowest. Therefore, all of the species tested in this study have the potential to be used commercially to prepare arnica salves and thus allow the A. montana population to re-establish itself. An additional finding was that A. chamissonis grew the best under greenhouse conditions, which may explain its substitution in some commercial salves.

Research of an Upstream DNA Sequence Gene of Fremyella Diplosiphon Regarding Regulation of Gfp Gene Expression in Response to Light Intensity

January 01, 2013 12:00 AM
David Tregaskis, Utah Valley University Biology Little is known about the details regarding gene expression which accounts for the light harvesting pigments in bacteria; specifically in the cyanobacteria Fremyella diplosiphon. The purpose of our experiment is to identify the upstream sequence that controls the expression of the scytonemin light harvesting pigment in Fremyella diplosiphon. This experiment will help us better understand the regulation and expression of genes that control light absorption. To test our hypothesis, that there is a regulating upstream promoter sequence for light sensitivity in Fremyella diplosiphon, we will culture the bacteria and extract its DNA. PCR will be performed to isolate the upstream sequence of the gene from Fremyella. Each plasmid was designed by adding restriction sites that will allow the proper cloning of the PCR fragment. This sequence will be introduced into the pSUN 199 and pSUN202 plasmids. These plasmids contain the GFP gene that will be activated by the promoter. The plasmids will be transformed onto Fremyella and analysis of gene expression will be done under different light conditions. This experiment will be able to identify the upstream regulatory sequence of the Scytonemin gene in Fremyella.

An Interactive, Taxonomy-Driven Tool for Genetic Sequence Database Mining

January 01, 2013 12:00 AM
Jarom Schow, Utah Valley University Biology DNA and protein sequence data from GenBank and other publicly available databases can be used to perform phlyogenetic analysis. However, the process of assembling data sets for taxa of interest using GenBank is a time consuming and labor-intensive manual process. To improve this process, we have developed a new set of software tools that identifies, organizes, and presents existing sequence data in a way to facilitate data set creation for organisms of interest. The software provides an interactive, taxonomy-driven user interface for viewing and selecting available gene sequence data and exporting it to common genetic analysis file formats. To identify available genetic data, the user selects one or more taxa (species, genus, family, etc.) of interest. The software then identifies all available sequence data for every member of the given taxa. The sequences are sorted by gene and taxon to determine availability and data coverage. Results are then displayed using a hierarchical taxonomy and list of sequence data organized by gene and availability. This enables the user to quickly identify which genes and taxa currently have the best coverage and select the desired data for export. A local database implemented with BioSQL and populated with sequence data from GenBank and taxa from the NCBI taxonomy database was used to access and organize the data. The software is written in C++ using the Qt framework for speed, robustness and cross-platform interoperability.

Student Perceptions and Knowledge of Evolution

January 01, 2013 12:00 AM
Tanner Mortimer, Utah Valley University Biology Nearly half of Americans reject evolution as an explanation of the origin of the diversity of life on Earth and rejection of evolutionary science has been shown to be correlated with a belief in a Christian God-creator (Gallup 2007; NSB 2010). The goal of this study is to explore the student perceptions and knowledge of Evolution at UVU in the non-majors and Biology majors introductory courses. Our study is designed to examine three hypotheses: Hypothesis 1 (Modern secularist): high levels of religiosity and fatalism should correlate with low levels of interest in science and scientific understandings of the world; Hypothesis 2 (Postmodern, postsecularist): no correlation between high levels of religiosity and fatalism, and interest in science and scientific understandings of the world; Hypothesis 3 (Social Psychology): that identifiable structural, contextual features will correlate with identifiable behaviors, irrespective of preexisting beliefs or previous behaviors. Due to the high % of LDS students that attend UVU, we are also interested in looking at the acceptance of Evolution among LDS before learning about the theory of Evolution (Pre-test) and after taking the introductory courses (Post-test). Preliminary results suggest that those students who had a strong sense of God-mediated control also had, in general, a negative attitude towards evolution.

The Effectiveness of Meloidogyne incognita and M. arenaria Specific Primers for North American Populations

January 01, 2013 12:00 AM
Brianna Rhoads, Utah State University Biology Nematodes are microscopic roundworms and are known to be some of the most difficult agricultural pests to control. Most of the 700 different plant parasitic nematodes species infect the root system of their host plant, causing galling, stunting and allow secondary pathogens to infect the host. For diagnostic purposes, in order to identify species of root-knot nematodes, the use of species specific primers can speed up the identification; many farmers need fast and reliable identification to determine which crops can still be planted in root-knot nematode infested fields. The purpose of my project was to test species-specific primers developed in Europe and Asia for Meloidogyne incognita and Meloidogyne arenaria on North American populations of both species using PCR. The results showed that primers developed in Asia and Europe for M. incognita amplified North American populations but primers developed in Europe for M. arenaria did not amplify North American M. arenaria populations. Based on results, M. incognita specific primers are useful for diagnostic purposes in the United States.

American Lichens: Do They Follow Latitudinal Gradients

January 01, 2013 12:00 AM
Robert Bradford, Utah Valley University Biology Most organisms exhibit latitudinal gradients in diversity (i.e., taxonomic richness decreases as latitude increases). Few studies have sought latitudinal gradients in lichens, especially in the midlatitudes. Our primary questions were: 1) do lichens along the west coast of the United States show latitudinal gradients? 2) If so, what is the rate of change and does the level of taxonomic richness affect this rate? We hypothesized that lichens would show a reverse latitudinal gradient in the region, as has been documented for lichens elsewhere in the northern hemisphere, but at a considerably smaller scale. This study fills in the gap in our understanding of lichen latitudinal gradients over large areas of North America. It also functions as a baseline for future climate change and conservation efforts. Our study area is bound at the south by the California-Mexico border (32.331° N) and at the north by the Washington-Canada border (47.178° N), and extends inland from the coastline to the crest of the Sierra Nevada Mountains (116.083° W, at its eastern -most point). We divided the region into 218 roughly equal-area (cite) grid cells using GIS, each bordered with latitudinal and longitudinal lines. We derived a list of all vouchered lichen specimens in each grid cell using Consortium of North American Lichen Herbaria, an online database. The data were synonymized, and species, generic, and familial richness were calculated for each grid cell. We found no correlation (R2 = 0.2306) between latitude and species richness, using the raw vouchered data. What we did find was a strong correlation (R2=0.9069) between sample density and species richness. These results are biased by sample density and do not reflect what is naturally occurring. We hypothesize that we can get an unbiased estimate of richness with MaxEnt models. Using the georeferenced lichen distributions and related climate data, we constructed species distribution models of all species with five or more occurrences (990 species). In GIS, we projected all 990 distribution models and our 218 grid cells together to calculate species richness for each cell at various thresholds (i.e. likelihood of occurrence at 10%, 20%, 30%, etc.).

Increasing Yield and Physical Properties of Dragline Spider Silk from Argiope Aurantia Through the Use of Synthetic Biology

January 01, 2013 12:00 AM
Ryan Putman, Utah State University Biological Engineering Spider silk is a biomaterial with extraordinary physical properties. It has a unique combination of tensile strength, elasticity, and even biocompatibility that has sparked interest in a wide range of disciplines. Potential implementations of spider silk include: medical advances (skin grafts, biomedical sutures, and artificial tendons/ligaments), automotive safety (seat belts, airbags), and military applications (parachutes, body armor). Although spider silk has a great variety of possible uses, collecting this product is not as easy as merely farming spiders and harvesting the silk. Spiders are naturally territorial and cannibalistic, thus alternative means of production are necessary to generate enough spider silk for realistic use. A non-pathogenic laboratory strain of Escherichia coli commonly used for research purposes will be modified to produce synthetic spider silk. Through the use of synthetic biology and molecular cloning techniques, recombinant DNA is inserted with the genetic code for dragline silk of the Argiope aurantia spider; once constructed, this DNA is transformed into E. coli. The goal is to take advantage of E. coli’s ability to be used as a “factory” for creating silk in a controllable and cost efficient system. Supplementation of additional tRNAs will be employed as a strategy to extend cell life and boost the overall spider silk protein yield. Preliminary results have been obtained that show the production of synthetic spider silk by the engineered E. coli. More research is being conducted to increase yields so that we can one day take advantage of this amazing biomaterial.

A New Approach to Creating Pradimicin-Type Antifungal/Antiviral Compounds

January 01, 2013 12:00 AM
Thomas Anderson, Utah State University Biology Pradimicin, a small molecule produced by the soil bacterium Actinomadura hibisica, is a promising candidate as a combined antifungal/antiviral therapeutic. It is active against a broad-spectrum of opportunistic, pathogenic fungi, interferes with the replication of influenza virus, and inhibits the reproduction of HIV-1. Toxicity and solubility problems have hindered past efforts to develop pradimicin as a therapeutic. Our research focuses on elucidating the bio-synthetic pathway of pradimicin in order to design and chemoenzymatically create pradimicin structural analogs with improved solubility and activity, and less toxicity. Several enzymes in pradimicin biosynthesis have been identified. We intend to characterize one of the key enzymes, PdmS, a putative glycosyltransferase, and to manipulate its gene to create novel, more efficacious pradimicin analogs. This project is funded for three years by the NIH NIAID (3 years). Methods: A gene knockout experiment was used to determine the role of PdmS in pradimicin production. Bio-synthetic precursors of pradimicin were subjected to bio-transformations in E. coli with recombinant genes for PdmS and another glycosyltransferase, OleD, to generate analogs with new sugar attachments. Analogs of pradimicin will be screened for bio-activity using standard microbroth dilution assay techniques. Confirmed results: The enzyme PdmS was identified and characterized as a glycosyltransferase. Expected results: newly created analogs of pradimicin exhibited minimal inhibitory concentrations of 10μg/mL against Candida albicans. Conclusion: Knockout of pdmS yielded the pradimicin aglycon, which confirmed the function of this glycosyltransferase and provides a start molecule for further structural modification to yield new analogs for bioactivity studies.

Fluorene as a Model Compound to Investigate Fire Induced Soil Water Repellency: A qualitative approach

January 01, 2013 12:00 AM
Vance Almquist, Utah State University Plants, Soils, and Climate Fire induced soil water repellency has been characterized across a variety of soils and landscapes as being a cause of watershed degradation and surface water pollution. The repellency is due to the condensation of volatile polyaromatic hydrocarbons onto soil particles. Although repellency is known to reverse, in some locations the reversal takes months; whereas, in other locations it may take years. Little is known about the reversal mechanisms and how they lead to such a large range of reversal times. Access to untreated fired-affected sites, can be unpredictable and samples vary greatly from site to site. Therefore, a model compound that mimics fire-induced soil hydrophobicity is needed to be able to systematically investigate soil hydrophobilicty reversal mechanisms. Fluorene is a relatively non-toxic, hydrophobic polyaromatic hydrocarbon. The behavior of fluorene coated sand grains was investigated under laboratory conditions using quartz sand. Moreover, its fluorescent properties could be used to non-destructively monitor its degradation over time. In this context fluorene was studied as a possible model compound for the study of mechanisms involved in the reversal of fire-induced soil hydrophobilicy. The compound was subjected to conditions known to degrade or reverse water repellency including temperature, UV-light, and moisture content. Changes in hydrophobicity were monitored using the ethanol drop test and fluorescent imaging. Digital image processing techniques with the public domain software, ImageJ, produced by the National Institute of Health, were used to analyze the images and generate spatial maps of treatment effects on fluorene degradation and hyrdophobicity reversal. Our results indicate that the hydrophobic fluorene-coated sand layers were degraded by treatments such UV light known to reverse hydrophobicity in fire-affected soils, thus suggesting that fluorene may serve as a suitable model compound for producing hydrophobic layers on course grained material.

Toxin-Degrading Bacteria: Herbivorous Rodents May Provide a Source of Novel Microbes for Agricultural Herbivores

January 01, 2013 12:00 AM
Ashley Stengel, University of Utah Biology Agricultural herbivores, such as cattle, often encounter plants containing toxins. One class of toxins, tannins, bind to proteins and inhibit digestive enzymes from acting to liberate nutrients. In this way, tannins prevent optimal absorption of nutrients. To overcome this challenge, some herbivores host bacteria with the ability to degrade tannins. Currently, there is a push to find novel microbes capable of aiding animals in detoxifying these compounds. Therefore, we aimed to isolate tannin-degrading bacteria from the desert woodrat (Neotoma lepida), a wild, herbivorous rodent that feeds largely on a tannin-rich shrub, creosote bush (Larrea tridentata). Woodrat feces were cultured on tannin-treated media, and bacteria capable of degrading tannins were further characterized with DNA sequencing. Results revealed that from 9 isolates, three species of tannin-degrading bacteria were present: Enterococcus faecalis, Bacillus subtilis, and Escherichia coli. Further characterization was performed through measurement of tannase activity. The activity of each isolate varied significantly between bacterial species as well as within a species. Ultimately, I hypothesize that these tannin-degrading bacteria facilitate the ingestion of tannin-rich plants by woodrats. Additionally, this research exemplifies how wild herbivores, such as the desert woodrat, provide an essential source of tannin-degrading microbes that could be introduced into domestic herbivores in order to improve agricultural practices.

A Preliminary Assessment of Mercury Concentrations in a Terrestrial Songbird on Antelope Island

January 01, 2013 12:00 AM
Heather Reynolds, Westminster College Biology The presence of mercury in a food chain can have harmful effects, including altering behavior, on organisms. Mercury is typically found in aquatic ecosystems, however recently is also recognized as a potential problem in terrestrial ecosystems. High levels of mercury have been found in the Great Salt Lake in a form able to bioaccumulate up the food chain. If the aquatic ecosystem is linked to the terrestrial ecosystem, then some of the highest predators included in this food chain may be songbirds that eat spiders. We quantified mercury in the blood of the Loggerhead Shrike, Lanius ludoviciaus, on Antelope Island. Upon being caught, the birds were measured, color banded, and a blood and feather sample taken from each of the 15 shrikes to be tested for mercury. Mercury concentrations ranged from 0.96 to 4.00 ppm, with a mean 1.14+/0.31 ppm. Sub-lethal effects in songbirds from another study were seen with concentrations ranging from 2.0-3.5 ppm. Two shrikes we tested exceeded that range. There was high variability in concentrations of mercury, which might be related to distance from shore. These preliminary data demonstrate that some mercury from the aquatic ecosystem is bioaccumulating in the terrestrial ecosystem on Antelope Island, and there may be harmful levels in the birds which could lead to change in behavior, and eventually decline in population. Future studies will investigate the costs of mercury contamination.

Total Mercury and Methylmercury in Water and Brine Flies from Two Distinct Sites at the Great Salt Lake

January 01, 2013 12:00 AM
Jeff Collins, Westminster College Biology The Great Salt Lake (GSL) has some of the highest mercury concentrations ever measured in surface waters. The accumulation of high levels of mercury, particularly its more toxic and readily biomagnified form, methylmercury, has been recorded in many species that inhabit or feed directly in the GSL, including waterfowl. However, no studies at the GSL, and very few studies elsewhere, have investigated the transfer of mercury from aquatic ecosystems to terrestrial ecosystems. We hypothesized that brine flies are able to accumulate mercury during their larval stages in the lake, then transfer this mercury to adjacent terrestrial ecosystems when they become flying adults. Concentrations of total mercury (HgT) and methylmercury (MeHg) were measured in samples of surface water and brine flies (larvae, pupae, and adults) collected once each month between February and July at Antelope Island, in the GSL. Samples were collected from two distinct sites: one along Gilbert Bay on the west side of the Island, and the other along Farmington Bay on the east. On average, HgT concentrations are greater in water samples from Farmington Bay (19.3 ± 9.0 ng/L unfiltered; 13.5 ± 10.1 ng/L filtered) compared to Gilbert Bay (8.5 ± 7.5 ng/L unfiltered; 9.2 ± 9.6 ng/L filtered). MeHg and HgT levels in brine flies displayed the opposite trend, with higher levels at Gilbert Bay (567 ± 123 ppb HgT; 425 ± 12 ppb MeHg) than at Farmington Bay (270 ± 60 ppb HgT; 208 ± 35 ppb MeHg). Potential explanations for the trends observed will be discussed.

Assessing the Impact of Urbanization on Stream Health

January 01, 2013 12:00 AM
Morgan Anderson, Westminster College Environmental Studies Emigration Creek, part of the Salt Lake City watershed, runs through Westminster campus at two points: by Garfield school and through main campus. We assessed several measures of water quality, to understand the impacts of anthropogenic activities and urbanization on this stream ecosystem. Additionally, we identified areas for restoration with the ultimate goal of reintroducing the endangered native Bonneville Cutthroat trout. Beginning in June 2012, we monitored the creek monthly, and will continue for a full year’s time. We assessed the structure and stability of the stream along with dissolved oxygen, pH, temperature, and turbidity. The macroinvertebrate community composition was analyzed also as a biological indicator of stream health. Along both reaches lack of vegetative cover, lack of large rocks to support the lower banks, and scouring and deposition along the steam bottom were common. We found that for all water quality measures monthly average levels were in acceptable limits for trout populations except for dissolved oxygen. Dissolved oxygen dropped below optimal levels in July and August, most likely due to an increase in water temperature. We found that both reaches have moderate species diversity of macroinvertebrates, though the community is dominated by species that thrive in water highly polluted with organic waste. Preliminary results suggest that the current condition of Emigration Creek is not optimal for cutthroat trout, largely due to seasonally low dissolved oxygen levels and lack of preferred food. Continued monitoring, along with a comparative study of nearby creeks, will further our understanding of the impacts of urbanization and the restoration efforts needed to support native fish populations in the Salt Lake Valley.

Establishing Two-point discrimination of Cranial Nerve V

January 01, 2013 12:00 AM
Kristie Williamson, Weber State University Athletic Training Context: Cranial Nerve V (CN V; Trigeminal nerve) is responsible for facial sensation. CN V has three separate branches which include ophthalmic, maxillary and mandibular. The ophthalmic nerve (V1) carries sensory information from the forehead; the maxillary nerve (V2) carries information from the cheek; and the mandibular nerve (V3) carries information from the chin. It is important to test all three areas of cranial nerve V to accurately assess full nerve function. Previous research has indicated that pressure threshold is not affected by age, however, normative values for two-point discrimination for CN V have not yet been established and may prove useful in concussion evaluation. Objective: Initial investigation aimed at determining gender-specific normative values for CN V two-point discrimination. Design: Prospective repeated-measures design. Setting: This study was performed in the athletic training facilities on the campus of a large Division I institution. Patients or Other Participants: Convenience sample of 106 healthy students enrolled at our institution (43 females, average age: 23.2; 63 males, average age: 22.1). Participants had no history of concussion within the last year, no facial scaring or plastic surgery and not a current smoker. Interventions: Measurement was taken using a two-point discriminator (Disk-Criminator) on the mid-forehead, mid-cheek, and mid-chin. Participants closed their eyes while each measurement was taken. Light pressure was applied (force equal to approximately 10-15 grams to produce blanching of the skin). Measurements were taken three times on each of three facial locations, sequentially. The smallest number in millimeters (mm) to correctly discriminate one/two points was recorded. The two pressure points were applied at exactly the same time. Main Outcome Measure: Discrimination score for each test location (mid-forehead, mid-cheek, mid-chin). Nested average was calculated within subjects for each test location; average was calculated between subjects for each test location. One-way between-subjects ANOVAs were conducted to evaluate potential differences in gender for each test location. Results: Between-subjects average for mid-forehead was 7.8mm (+/2.9), for mid-cheek was 10.4mm (+/2.6), and for mid-chin was 5.9mm (+/1.9). There was a significant effect for gender for cheek normative value (p<0.01); average discrimination score for males was 11mm, average for female was 9.7mm.

On Creating a Forensic Herbarium for Weber County,Utah

January 01, 2013 12:00 AM
Jackie Parker, Weber State University Botany Forensic researchers as well as law enforcement officials rely heavily on herbarium type specimens for field investigation. An electronic catalog could greatly assist forensic professionals by providing easy access to area specific specimens. The goal of this project was to compile a database and dichotomous key of native plants found in Weber County, Utah. Pollen and woody material resist degradation, making them perfect candidates for forensic analysis. Using the USDA plant database, all native flowering plants were identified (729 in total). Plant pressings, microscope slides, digital micrographs and line drawings were made of two-hundred native species to date. Pollen and woody tissue were gathered from representative plants and prepared for permanent herbarium collection. Woody tissue and pollen preparation had previously been optimized for best imaging results. Rudimentary dichotomous keys for both woody tissue and pollen were made using micrographs and line drawings to illustrate distinguishing features between plant species. As new species are prepared, they are included in the dichotomous key. The primary purpose of this collection is for it to be used by forensic investigators with limited botanical training. In the spring of 2013, field tests will be conducted to determine how effective the dichotomous key is when identifying unknown specimens. After the layout is finalized, the key will be presented to local law officials as an additional tool in the forensic repertoire.

Dietary Protein Complexity Can Influence Re-feeding Syndrome

January 01, 2013 12:00 AM
Stephanie Hansen, Weber State University Zoology Re-feeding syndrome is the result of the rapid re-introduction of nutrients following a period of severe malnourishment or starvation. During starvation, critical nutrient absorption and anabolic pathways are shifted to conserve energy and maintain cellular function in intestinal enterocytes. Rapid reintroduction of nutrients can often overwhelm the remnant absorptive ability of the intestinal tract, leading to complications such as, failure to thrive and intestinal failure. We hypothesized that a polymeric diet would improve refeeding response compared to an elemental diet. We utilized the nematode Caenorhabditis elegans (C.elegans) as a minimalist model of refeeding. We induced a developmental state of starvation known as, dauer, and then transferred animals into either a polymeric diet or elemental diet. We measured body length daily for 5 days until the worms reached adulthood. Data were statistically analyzed using a general linear model of analysis of variance and expressed as mean+/-SEM. Our results indicate that polymeric diet (695.6+/-25.2 ?m) demonstrated at least 10% (p<0.05) improved growth compared to elemental diet (646.8+/-21.7), with polymeric worms reaching adulthood by day 2 (960.2+/-26.9), whereas elemental animals required 3 days to reach adulthood (894.2+/-26.9 day 2, 972.6+/-27 day 3). Additionally, we assayed intestinal proteolysis by feeding the worms green fluorescent protein (GFP) and measuring fluorescence along the length of the intestinal tract. Our findings demonstrate a decreased rate (p<0.05) of intestinal proteolysis among worms fed exclusively a polymeric diet, despite no significant change in the rate of fluorescent protein intake. Our data confirm our hypothesis that a polymeric diet improves growth and development over an elemental diet. In addition, by requiring some hydrolytic digestion, growth is improved. These results might help to improve clinical management of refeeding syndrome as well as rehabilitate patients suffering intestinal failure.

Basal Pterygote Relationships and Its Implications for the Evolution of Flight in Insects

January 01, 2013 12:00 AM
Mark Tingey, Utah Valley University Biology The phylogenetic relationship of Ephemeroptera (mayflies), Odonata (dragonflies) and Neoptera (remaining winged insects) has been a problematic isse in insect evolution and systematics. Resolving their relationships is a critical step toward understanding insect diversification and the evolution of flight. Three hypotheses are evaluated so as to determine the phylogenetic placement of these three orders of insects: 1) Ephemeroptera sister to Odonata + Neoptera; 2) Monophyletic Paleoptera (Ephemeroptera + Odonata); and 3) Odonata sister to Ephemeroptera + Neoptera. Data from more than 260 taxa were collected from Genbank and assembled into a supermatrix representing 6 different molecular markers. Each of the genes were aligned and phylogenetic analyses were carried out utilizing a number of different methods including Bayesian, maximum likelihood, and parsimony frameworks in order to elucidate the relationships of these insect groups. The large number of taxa proved to be a daunting task, but provided new insights into the support for the different hypotheses. The implications for the evolution of flight were examined in light of the generated phylogenies.

Insects of Capitol Reef National Park

January 01, 2013 12:00 AM
Matthew Ethington, Utah Valley University Biology Although the insect fauna of the Colorado Plateau region are somewhat well known, our specific understanding of the diversity in Capitol Reef National Park is sparse. Here we present an overview of the insect diversity of the park based on a number of undergraduate student-led excursions to collect specimens. The collections will contribute to an increased understanding of the parks insect diversity and will result in an appropriately curated natural history museum collection. Furthermore, an insect field guide for the park will be created in order to serve as an educational tool for visitors to the park. Field collecting efforts, consisting of traditional insect collecting methods (aerial nets, aquatic nets, light traps, etc.) will be used. The collected material will be curated, photographed, and stored in a natural history museum (Brigham Young University ML Bean Museum). This presentation will be a summary of material gathered in the last three years.

Assessing Pro-Inflammator Biomarkers as Earl Indicars of Influenza Disease

January 01, 2013 12:00 AM
Makda Gebre, Utah State University Biology The first pandemic of the 21st century was the influenza A (H1N1pdm09) virus that originated in Mexico and killed 12,000 people within the United States. It now circulates as a seasonal influenza virus causing mild symptoms in most but still killing some susceptible individuals. Influenza A (H1N1pdm09) virus leads to acute respiratory distress syndrome (ARDS) in high risk patients and has a mortality rate of 40-50% in those patients. ARDS patients usually die before any intervention since there is no clinical evidence that can be used to detect it. To detect ARDS early in disease progression, we need to search and develop biomarkers that can be tested in the patient’s blood or fluids. The three biomarkers tested as potential early disease indicators in this project included: C-reactive protein (CRP), serum amyloid A (SAA) and Transferrin. To test these biomarkers, mice were infected with the influenza A H1N1pdm09 virus and serum was collected from the mice at different time points. Serum collected was tested for amounts of CRP, SAA and Transferrin using an enzyme-linked immunosorbent assay (ELISA) and spectrophotometer. Control mice were mock infected and also tested for the biomarkers for comparison.

Production of New Pyridine N-oxide by Bioconversion with Cunninghamella echinulata var. elegans

January 01, 2013 12:00 AM
David Gage, Utah State University Biological Engineering A new N-oxide was produced from 3-(N-Boc-aminomethyl)-5-bromopyridine by bioconversion with Cunninghamella echinulata var. elegans ATCC 9245, and its structure was established based on spectral data. The microbial N-oxidation is efficient and highly selective. The substrate was transformed into the product in 7 days.

Interaction of Chytrid Fungus and Normal Skin Biota in Amphibians

January 01, 2013 12:00 AM
Scott Nagao, Weber State University Microbiology Batrachochytrium dendrobatidis belongs to the fungal phylum Chytridiomycota (chytrids), and in 1999, was both identified as a new species and associated with causing chytridiomycosis in amphibians. Since its identification, this fungus has been implicated in rapid population declines in multiple amphibian species in North and Central America, Europe, and Australia. In adult amphibians, the fungus colonizes only the keratinized skin cells on the ventral and dorsal surfaces as well as on the webbing between the toes. Infection is associated with hyperkeratosis resulting in disruption of the skin’s osmoregulatory function, dehydration, electrolyte imbalance and death. There is data that indicates some bacteria that live on the epidermis of amphibians produce chemicals that inhibit the growth of B. dendrobatidis. However, this data is associated only with salamanders. There is no similar inhibitor data published for frog and toad species, and no data published on the identification of normal skin biota of frogs and toads. We have isolated over 175 bacterial isolates from 67 toads and frogs, extracted DNA, and used PCR to amplify the 16S ribosomal DNA gene. Amplicons have been sequenced to determine speciation based on genetics. This is the first report of normal bacterial skin biota in frogs. Further, a skin swab was also taken from these frogs and used to analyze which are infected with B. dendrobatidis via quantitative PCR screening. While the prevalence of fungal infection appears to be low, we have been able to correlate fungal-positive hosts with number and/or species of normal bacterial skin biota.

Determination of Microbial Populations in a Synthetic Turf System

January 01, 2013 12:00 AM
Jason Bass, Weber State University Microbiology There is growing concern regarding the contribution of infilled turf fields on increased athlete infections. Abrasions that occur on these fields create a portal of entry for pathogens such as Staphylococcus aureus. This study compares microbial populations on two infilled turf fields (year old vs. 6 year old turf). Infill material from both fields was sampled at three sites for 5 months during the football season (sidelines, middle of the field, and end of the field). Tryptic Soy Agar was used to determine total microbial load, MSA for S. aureus, and EMB Agar for coliforms such as Escherichia coli. Much higher microbial populations were found on the older turf field, a 1E+04 increase over similar locations on the new turf; suggesting microbial populations can accumulate in synthetic turf infill over time. On the older field the sideline has the highest counts with an average of 1.60E+08 CFUs/g of rubber infill. On the new synthetic turf, the area with the highest number of microorganisms was the end of the field rather than the sideline. This is probably due to where practices are held on the new turf field rather than actual game play. A high number of salt-tolerant, mannitol-fermenting bacteria (indicators of S. aureus) were also found (3.25E+02 CFUs/g on the new turf vs. 2.73E+03 CFUs/g on the old turf). Escherichia coli was isolated from the new turf, in an area of high usage. These results indicate that infill material can serve as a source for pathogens among athletes and that organisms accumulate over time posing a greater risk if proper cleaning is not routinely performed.

The Evaluation of the Balance and Stability Gains with Crutches using the Tru-Motion go Tip

January 01, 2013 12:00 AM
Jeffrey Pence, Utah Valley University Exercise Science Introduction:

NANOGP8: Evolution of a Human-Specific Retro-Oncogene

January 01, 2013 12:00 AM
Aaron Fairbanks, Utah Valley University Biology NANOGP8 is a human (Homo sapiens) retrogene, expressed predominantly in cancer cells where its protein product is tumorigenic. It arose through retrotransposition from its parent gene, NANOG, which is expressed predominantly in embryonic stem cells. Based on identification of fixed and polymorphic variants in a genetically diverse set of human NANOG and NANOGP8 sequences, we estimated the evolutionary origin of NANOGP8 at approximately 0.9 to 2.5 million years ago, more recent than previously estimated. We also discovered that NANOGP8 arose from a derived variant allele of NANOG containing a 22-nucleotide pair deletion in the 3? UTR, which has remained polymorphic in modern humans. Evidence from our experiments indicates that NANOGP8 is fixed in modern humans even though its parent allele is polymorphic. The presence of NANOGP8-specific sequences in Neanderthal reads provided definitive evidence that NANOGP8 is also present in the Neanderthal genome. Some variants between the reference sequences of NANOG and NANOGP8 utilized in cancer research to distinguish RT-PCR products are polymorphic within NANOG or NANOGP8 and thus are not universally reliable as distinguishing features. NANOGP8 was inserted in reverse orientation into the LTR region of an SVA retroelement that arose in a human-chimpanzee-gorilla common ancestor after divergence of the orangutan ancestral lineage. Transcription factor binding sites within and beyond this LTR may promote expression of NANOGP8 in cancer cells, although current evidence is inferential. The fact that NANOGP8 is a human-specific retro-oncogene may partially explain the higher genetic predisposition for cancer in humans compared with other primates.

Molecular Phylogeny of Mayfly Family Baetidae (Ephemeroptera)

January 01, 2013 12:00 AM
Chase Barker, Utah Valley University Biology The Baetidae are an important group of Mayflies because of their position on the mayfly tree of life in that they are a key to understanding key evolutionary trends, such as the origin of wings and flight. Phylogenetic relationships of mayflies are still not very well known, however molecular and morphological data have begun to shed light on the relationships of these insects (Ogden et al. 2009). Recent molecular and morphological analyses have examined relationships of some of the lineages of Baetidae distributed in different regions of the world (Gattolliat et al., 2008; Kluge, 1997; Monaghan et al., 2005; Nieto, 2010;). Most of these studies suggest two subfamilies, Baetinae and Cloeoninae. This study represents one of the largest (in terms of data) and most diverse (in terms of taxa) phylogenetic analysis performed on the family Baetidae to date. The dataset consists of more than 50 taxa sequenced for six genes (Nuclear 18S rDNA; Nuclear 28S rDNA; Histone 3, Mitochondrial COI, Mitochondrial 16S rDNA; and Mitochondrial 12S rDNA). DNA sequences were aligned in Muscle (Edgar 2004) and tree reconstruction and nodal support was performed under Maximum Parsimony, Maximum Likelihood, and Baysian frameworks. The results indicate that the subfamilies were not strongly supported as monophyletic, contradicting conclusions from morphological data. Missing data in the data set might be contributing to low support across the tree.

Impact of Cations on the Aggregation,Dissolution,and Phytotoxicity of Metal Oxide Nanoparticles in a Sand-Wheat Growth System

January 01, 2013 12:00 AM
Trevor Hansen, Utah State University Biology The use of metallic nanoparticles (NPs) in various applications presents the possibility for environmental contamination by these NPs. CuO and ZnO NPs have dose-dependent phytotoxicity. However, NPs are modified by different environmental factors such as salts: chlorides of Na, K, and Ca are used on roads for de-icing, dust control, irrigation, water treatments, and fertilizer production. At low concentrations these salts promote plant growth, but elevated concentrations become phytotoxic. This study examines the impact of Na, K and Ca chlorides on the phytotoxicity of CuO and ZnO NPs for wheat grown in sand. Atomic force microscopy and dynamic light scattering showed dose-dependent aggregation of the NPs in the wheat rhizosphere. The salts also caused NP-aggregation, but the degree of dissolution of the NPs was salt specific. Release of Cu from CuO NPs in the planted sand was reduced by all salt treatments whereas Zn release from ZnO NPs was reduced by Na and K but not Ca. Overall, a phytotoxic synergistic effect was seen at lower salt concentrations, but at higher salt levels, toxicity was mediated mainly by the salts. Therefore, effects upon plant growth of NPs and salts will vary according to concentrations.

Photobiology: Optimizing Light Quality to Maximize Plant Growth and Development

January 01, 2013 12:00 AM
Kevin Cope, Utah State University Plants, Soils, and Climate Photosynthesis is driven primarily by radiation between 400 and 700 nm; however, not all wavelengths are equally efficient. Red light (600 to 700 nm) is 25 to 35% more efficient than blue light (400 to 500 nm) and 5 to 30% more efficient than green light (500 to 600 nm). Although blue light is less efficient than red light, it has been shown to be necessary for normal plant development in all tested crop species. The mixture of pigments in plant leaves allows them to absorb all colors of light. Both red and blue light are absorbed primarily in the upper leaf. Green light penetrates deep into the lower leaf and transmits to leaf layers below the upper leaf canopy. Accordingly, once the upper canopy is saturated with red and blue light, supplemental green light is beneficial in increasing whole plant photosynthesis. Although the effect of spectral quality on single leaves is well characterized, the effect on whole plant growth and development is poorly understood. The narrow spectral output of LEDs makes them particularly effective for photobiological studies. From our initial studies with radish, soybean, and wheat, we determined that blue light levels can be used to better predict plant development than red:far-red light ratios. We also found that plants require at least 80 μmol of blue photons m-2 s-1 in order to develop normally. Further studies are currently being conducted to determine the optimal ratio of red and green light for maximizing whole plant photosynthesis in lettuce and radish.

Rationally Modified Tumor Suppressor Protein p53: A Possible New Cancer Treatment

January 01, 2013 12:00 AM
Thomas Wallace, University of Utah Pharmaceutics and Pharmaceutical Chemistry The tumor suppressor p53 is mutated in more than 50% of all cancers, while the majority of remaining cancers contain mislocalized p53(1). p53 is part of a network of cellular pathways that regulate growth, cell cycle arrest, and clearly delineated apoptotic pathways(2). Restoring the function of p53 can be seen as an ultimate cancer treatment. Restoring p53 would activate an already existing cell pathway that prevents cells from becoming cancerous and cause cancer cells to go through apoptosis. Playing a role in tumor suppression has made p53 an attractive target for gene therapy. However, despite the potential of p53 as a powerful treatment, it is limited by the dominant-negative effect of dysfunctional mutant p53. This effect imposes one of the greatest limits on the effectiveness of a p53 based treatment. This project is focused on bypassing the dominant-negative effect of dysfunctional p53 over exogenous functional p53. The attempted solution was substitution of the p53 binding domain with a different but structurally analogous coiled-coil, based on a modified Breakpoint cluster region (Bcr) protein. By doing this, the dominant-negative effect of mutant p53 may be bypassed. The purpose of this project has been to synthesis and test rationally modified forms of p53 with modified Bcr coil that are introduced into cells via a plasmid to restore cellular p53 activity. In vivo cell tests have already shown the effectiveness of these constructs at causing higher rates of cell death in cancer cells and constructs are currently being refined to carry forward to xenograft model animal trails. The ultimate goal is to develop a treatment for human cancer patients where modified p53 will selectively cause apoptosis in cancer cells.

Experimental Evolution of Feather Louse (Columbicola Columbae) Parasite Body Size

January 01, 2013 12:00 AM
Heidi Montgomery, University of Utah Biology Parasites are arguably the most diverse group of organisms on the planet. One key factor in determining patterns of parasite biodiversity is the number of host species a parasite can infect, or its host specificity. However, surprisingly very little is known about the evolution of host specificity. Here I use domesticated pigeons (Columba livia) and their ectoparasitic feather lice (Columbicola columbae) to demonstrate how parasite body size influences host use. The current study has two main goals: 1) to use different sized hosts to experimentally evolve louse body size, and 2) to determine how parasite body size effects host specificity. Four breeds of domesticated pigeons were infested with parasitic feather lice. After roughly six generations, mean louse body size changed with respect to host body size, with the largest pigeons having the largest lice. Interestingly, the smallest pigeons had larger lice as well. However, this increase in louse size appears to be the result of a change in microhabitat use, with lice shifting from predominantly the wings and tail to the head. This study is one of the first to experimentally demonstrate how changes in parasite morphology and behavior influence the evolution of host specificity.

The Role of Aggression in the Evolution of the Human Hand

January 01, 2013 12:00 AM
Joshua Horns, University of Utah Biology There are numerous arresting differences between the hands of humans and those of chimps, principally among them the shortening of metacarpals 2-5, the relative increase in length of the thumb, and the development of separate musculature controlling flexion of the thumb. In addition to improving manual dexterity, these changes allow humans, in contrast to chimps and other apes, to make a buttressed fist with the phalanges pressed against the central palm and the thumb adducted onto the dorsal surface of the phalanges. We believe this hand posture greatly reduces the strain experienced by a fully formed fist when striking with force, thereby rendering the human hand as a more effective weapon. We tested this idea by manipulating the tendons in a cadaver arm to induce the hand to form into buttressed and non-buttressed conformations, and then tested each conformation by having the hand strike a hanging instrumented mass to measure the force of each strike. Additionally, the 2nd metacarpal of the hand was fitted with a strain gauge so that strain in the bone could be compared to the force of the strikes. The results of these tests showed that there was a significant drop in strain in the buttressed fist (in comparison to the non-buttressed) for a given force.

The Effect of Non-tutoring Social Interaction on Learned Birdsong

January 01, 2013 12:00 AM
Jason Chen, University of Utah Biology Both human language and birdsong are learned sensorimotor processes that require exposure to adult communication signals in order to be reproduced. The social aspect of the development of these vocal signals is distinctive because interaction is not required for the development of vocal signals in other organisms. Human infants isolated from interaction will not learn to speak normally. The need for interaction is also characteristic of the ontogeny of vocal signals in the zebra finch (Taeniopygia guttata), but only zebra finch males develop vocal signals, in the form of song. Juveniles raised in isolation will develop highly atypical song characterized by prolonged, monotonic syllables and irregular rhythms. When juveniles are tutored by these isolated birds in one-on-one conditions their song drifts towards normally raised birds. It is unclear how tutoring, as a social interaction, influences this observation. We hypothesized that different social experience influences birdsong. We predicted the song of juveniles raised in isolation with an experienced female to be closer to normal song than that of those raised in isolated sibling groups, or those raised in isolation. Current data suggest that the syntax and temporal features of song from juveniles raised in isolation with experienced females is indeed closer to normal song than that of isolated juveniles.

Strength in Numbers: Behavioral Response of Speckled Dace

January 01, 2013 12:00 AM
Travis Wood, Southern Utah University Biology Speckled dace, Rhinichthys osculus, is a small minnow that occupies river systems in Utah, Arizona, and Nevada. These minnows prefer clean, faster-moving water with plenty of cover such as rocks or undercuts. The invasive crayfish Orconectes virilis inhabits areas where the Virgin spinedace is found and has a similar diet being an opportunistic feeder. I tested the hypothesis that the natural behavior of Virgin spinedace will be altered due to the presence of crayfish. I predicted that the spinedace would avoid the crayfish and stay out in the open exposing them to a higher risk of predation, since crayfish are a more aggressive organism and will try and eat virtually anything they come into contact with. The experimental trials were conducted (N=24) in Quail Creek, Utah. Large plastic bins with the front and back replaced with screen were used to allow water flow through our experimental chambers. Each bin was placed in the creek and had rocks, and an undercut bank to resemble the native habitat. Controls consisted of placing isolated Virgin spinedace in one of the bins to observe its behavior. In both controls and experimental trials, either 2 spinedace, or 5+ spinedace were added. In experimental trials, I introduced 2 crayfish into the experimental chambers with the Virgin spinedace and allowed them to acclimate for 10 minutes. After the 10 minute acclimation period, behavioral observations were made. Results indicated that when 2 spinedace were present along with the crayfish, they would stay out in the open and the crayfish would occupy the cover or undercut. When 5+ spinedace were present with crayfish, the spinedace displayed a mobbing or “strength in numbers” behavior where they would occupy the undercut and either clog it up with their presence so the crayfish would leave, or mob the crayfish to make them leave. This behavior was opposite of what I predicted would happen. Since this mobbing or “strength in numbers” behavior was not observed with the samples of just 2 spinedace, this may be a behavioral adaptation resulting from the presence crayfish. Further research can be done on the behavioral effects of various fish species in the presence of introduced or invasive species to determine if this behavior is seen in other fishes.

Feeding Strategies and Prey Preferences in Predacious Leeches

January 01, 2013 12:00 AM
Heather Shumway, Southern Utah University Biology Glossiphoniids are jawless leeches that feed using a proboscis, which they use to impale prey so that they can feed on their prey’s blood and tissues. This study focuses on two different species, Glossiphonia complanata and Helobdella stagnalis. Helobdella stagnalis feed on a variety of prey, including bloodworms and freshwater snails, often feeding together in large groups. When a prey item is placed in the container, H. stagnalis immediately begin smelling the water and moving toward the prey. After the first H. stagnalis makes contact and secures prey, other individuals within the group will move to that area, often passing prey along the way, to attach to the same prey item. Once a number of individuals have started feeding, the prey is often broken into smaller pieces and individuals can then begin feeding on various sized pieces. This is in contrast to members of the species Glossiphonia complanata, who appear to be selective with their prey, and have been observed going up to 4 weeks without feeding, even in the presence of their non-preferred prey (bloodworms). When preferred prey (freshwater snails) were placed in the container, unfed G. complanata did not immediately begin smelling the water or initiate hunting. Unlike H. stagnalis which feed in groups, G. complanata appear to prefer feeding alone, and have even exhibited competitive behaviors.

Ability of Wolf Spider’s (Lycosidae) to Assess Their Nutritional Needs and Deficiencies

January 01, 2013 12:00 AM
Sarah Miller, Southern Utah University Biology As humans, we have the ability to change our diets if we are deficient in any specific nutrient. Many animals have the ability to change their diet if they are deficient in nutrients. However, for many carnivores, it is generally thought that a prey item will have the same nutritional composition as the predator body composition. Carnivores are limited nutritionally in their diet. This means that they only get nutrients from the prey that they are able to locate to consume. This study is investigating prey choice of invertebrate predators (wolf spiders) when their prey item has been altered to be deficient in one specific nutrient (lipid or protein). I predict that the spiders will be able to choose the correct prey item for the nutrient in which they are deficient. The total weight of flies eaten in each treatment will be measured to determine if wolf spiders select prey items based on the nutrient content of the prey. Results will be analyzed using a nested ANOVA.

Developing Recipes That Reduce The Fat Content In Baked Foods Where The Fat Substitutes Are Common Foods

January 01, 2013 12:00 AM
Sarah Miller, Southern Utah University Agriculture and Nutrition Science The high intake of fat in the average American diet is a growing concern to the nutritional community. High levels of total fat intake increase cardiovascular disease (CVD) which is the number one killer in America. The successful development of low fat recipes that can be accessed and produced by the general population is valuable to the fight against obesity and CVD. If acceptable products can be made with lower fat content then it is possible to lower the fat intake in a person’s diet. This study is designed to test the acceptability of low-fat desserts using every day food products available for home use as fat substitutes. Four popular “name-brand” recipes were altered by removing 55-73% of the fat and replacing it with a common food item, either pureed white or pinto beans, applesauce or yogurt. Southern Utah University students were recruited via flyers, in class announcements, and word of mouth. Participants (n=56) were asked to taste and evaluate the four products. Afterwards they completed a short survey about their knowledge of low-fat food substitutes and acceptability of the products. Results and conclusions forthcoming.

Tissue Specific Isolation of Nucleosomes in Caenorhabditis elegans

January 01, 2013 12:00 AM
Hyrum Shumway, Brigham Young University Microbiology and Molecular Biology Epigenetics is the study of factors of gene regulation that do not stem from the primary DNA sequence. One such example of epigenetic gene regulation is where DNA wraps around histone proteins to form nucleosomes. The positioning of nucleosomes is the first order of control for genic transcription. Wrapped DNA is less accessible for transcription compared to DNA that is nucleosome free. Model organisms for human epigenetics such as the nematode Caenorhabditis elegans are invaluable because of their ease in manipulation and because the components of nucleosomes (histone proteins and DNA) are highly conserved across phylogeny. The purpose of my particular research is to develop and validate a new protocol for tissue-specific isolation of nucleosomes through immunoprecipitation in young adult C. elegans. This protocol leverages green fluorescent protein fused to histones to research nucleosome positioning in the germ-line cells of C. elegans nematodes. When successful in our animal model, this procedure is the first step in allowing analysis of chromatin architecture of any tissue at any developmental or disease state including human cells. The widespread prevalence and implications of human disease is staggering in magnitude. Research is ongoing to decrease morbidity, increase prevention, and fight infection. With epigenetic tools, this vital research is benefitted and supplemented.

The Role of Timing of Dietary Selenium and Isoflavone Supplementation in the Reduction of Prostate Cancer Risk Factors in TRAMP Mice

January 01, 2013 12:00 AM
Ji Su Park, Brigham Young University Nutrition, Dietetics, and Food Science Selenium (Se) and soy have each been shown to reduce risk for prostate cancer when consumed at high levels. The purpose of this project was to define the molecular mechanisms of prostate cancer chemoprevention by Se and soy, and to describe how timing of dietary treatment modifies those effects. [C57BL/6 X FVB] F1 TRAMP (TRansgenic Adenocarcinoma of Mouse Prostate) male mice were fed stock diets high or low in soy, with or without a supplement of Se (4.0 mg Se/kg BW as Se-meth- ylselenocysteine) by gavage 5 d/wk in a 2 X 2 factorial design. Mice were exposed to different diets starting from conception, 6 weeks, or 12 weeks of age and were sacrificed at 18 weeks. Three-way ANOVA showed that supplemental Se increased serum and liver Se, with significant interactions with both time and soy intake. Selenium dosing decreased BW independent of soy intake and time of dietary intervention. Both Se and soy decreased epididymal fat pad weights, with Se’s effects being more pronounced in mice exposed to diets from conception than from 6 wk. Urogenital tract weights, a measure of prostate proliferation and tumor volume, were significantly reduced by Se supplementation (P<0.001) and soy (p=0.044), independent of time of dietary intervention. Histological examination of mouse prostates is in progress to determine dietary effects on disease progression. These data suggest that, in this model, chemopreventive efficacy of Se and soy does not differ between prenatal and early post-natal introduction.

“Killing Me Softly”: The Economic Toll of Forest Fire Repression

January 01, 2013 12:00 AM
Adam Olson, Brigham Young University Plant and Wildlife Sciences Forests systems of the Central Rocky Mountains rely on an intricate balance of natural disturbance cycles in order to develop properly. Forest fires are one such disturbance, however, certain fire characteristics, particularly fire severity, can vary widely across forest landscapes. In our study, we examined the influence of fire severity on aspen regeneration as well as aspen defense against wildlife and livestock browsing. Our results indicate that high or moderate burn severity is more favorable to aspen regeneration and survival. These areas of severe burn result in a higher density of aspen suckers, more vertical and lateral growth, greater chemical defense concentrations, and less browse damage than the neighboring plots of low or no burn. This data suggests that fire severity should be taken into account when considering plant regeneration and susceptibility to browse damage in burned landscapes.

The Effect of Male Dominance on Female Mate Choice in Poecilia gillii

January 01, 2013 12:00 AM
Michael McEntire, Brigham Young University Biology Female mate choice (intersexual selection) and male dominance interactions (intrasexual selection) can each play important roles in sexual selection. These two mechanisms tend to be discussed in isolation. The goal of this study is to explore the interaction between these two forms of sexual selection. To test this idea, we focused on the livebearing tropical fish system Poecilia gillii. We grouped males into similarly sized pairs and observed them for a week to determine which male was dominant. These pairs were then presented to females in mate choice trials to ascertain female preference. We also photo- graphed the males to determine coloration. We found that females were unable to detect dominant males without viewing the physical contest and that carotenoid coloration bore no effect on female preference. Females tended to choose the male to their left, suggesting the preferential use of their right eyes in making decisions on mate choice.

Characterization of Yeast PAS Kinase Through Random Mutagenesis

January 01, 2013 12:00 AM
Kayla Bevard, Brigham Young University Microbiology and Molecular Biology Metabolic diseases, such as obesity and diabetes, are endemic in American society. Mutations in PAS kinase, a recently discovered sensory protein kinase, have been shown to cause Maturity Onset Diabetes of the Young (MODY) in humans (Semplici et al., 2011). In addition, PAS kinase deficient mice, when placed on a high fat diet, display phenotypes related to diabetes including resistance to weight gain, insulin insensitivity and triglyceride accumulation (Hao et al., 2007). PAS kinase consists of a sensory PAS domain that binds to and inhibits the kinase domain (Amezcua et al., 2002). Our model for PAS kinase activation involves the generation of a small molecule ligand that binds to the PAS domain and relieves this inhibition. We are currently engaged in several yeast genetic screens which will identify regions in the full length PAS kinase protein that are essential for either PAS kinase activation or for binding of its substrates. The first screen is based on the ability of PAS kinase, when overexpressed, to rescue a temperature-sensitive mutation in Tor2, the tor2(ts). We have isolated both point mutations and truncations in PAS kinase which alleviate the tor2(ts). These mutations solidify our model for PAS domain inhibition and will identify novel regions involved in PAS kinase regulation. Our second screen uses the yeast 2-hybrid to select for both point mutations and truncations that increase the affinity of PAS kinase for its substrate, Pbp1. These mutations will help identify key regions of PAS kinase utilized in substrate recognition. Finally, we will compare the regions affected by our mutations with the regions of PAS kinase that we have found to be well-conserved throughout evolution. Analysis of these specific genetic regions will help elucidate the molecular mechanisms involved in the regulation and function of PAS kinase, a key player in the development of metabolic disease.

GPR55 Modulates the Cellular Mechanism Behind Memory Formation, Suggested Alternative Pathways Require Further Investigation

January 01, 2013 12:00 AM
Spencer Bell, Brigham Young University Physiology and Developmental Biology The hippocampus functions as the memory formation center of the brain. As memories are formed, brain cells in this area undergo changes by which connections between them are either strengthened or weakened, processes known as long-term potentiation (LTP) and long-term depression (LTD), respectively. Receptors located on these cells modulate these processes as they are activated by chemical signals known as neurotransmitters. We sought to examine the effects of a receptor known as G protein-coupled receptor 55 (GPR55) on LTP and LTD in the rodent hippocampus by applying agonists of the receptor, or chemicals that artificially activate it, to brain slices preserved in artificial cerebrospinal fluid. O-1602 is a purported synthetic agonist of GPR55. When we applied O-1602 to rat hippocampal slices during electrical induction of LTP, the magnitude of LTP was decreased when compared to controls. When LTD was induced in the rat hippocampus in the presence of O-1602, no significant difference was observed when compared to controls. Further experimentation involved the application of lysophosphatidylinositol (LPI), a naturally occurring GPR55 agonist, to genetically-engineered knock-out mice which lacked expression of GPR55. LPI is generally considered a more reliable agonist of GPR55, but caused enhanced LTP in wild-type mice which expressed GPR55 when compared with knock-out mice. This inconsistency and other inconsistencies in our data while using O-1602, while perhaps due to other physiological differences between rats and mice, may suggest the possibility that O-1602 activates a receptor other than GPR55. Our further research will seek to investigate this possibility.

The Association Between Pattern Separation and Depression

January 01, 2013 12:00 AM
Matthew Schneider, Brigham Young University Physiology and Developmental Biology Alzheimer’s disease, the most common form of dementia, affects millions of people per year. Research has shown that Alzheimer’s affects the hippocampus brain region, which is involved in learning and memory. Understanding learning and memory functions is imperative to comprehending both healthy brain functions and Alzheimer’s disease. Many researchers seek to understand both the causes and treatments of the disease, but tangible information remains elusive. Studies thus far have shown that to encode memories, the brain must change neural synapses to either strengthen or weaken those pathways, a process known as synaptic plasticity. Using electrophysiology techniques on mouse hippocampal slices, this project will provide further insight on memory formation and regulation by imitating synaptic plasticity mechanisms. I will look at a specific cellular pathway involving the protein receptor GPR55, which has recently been shown to induce synaptic plasticity. By understanding how the GPR55 pathway functions, this research will contribute to the understanding and treatments of Alzheimer’s and other neurodegenerative diseases.

Association of the CETP Gene with Cognitive Decline and Dementia in the Cache County Study

January 01, 2013 12:00 AM
Caitlin Munger, Brigham Young University Biology Alzheimer’s is a fatal, non-treatable neurodegenerative disease and the most common cause of dementia. While no one gene has been found to determine the development of Alzheimer’s, past studies have established a strong hereditary influence on Alzheimer’s. So far, only 5 genes have been found which replicably contribute to the genetic risk of developing Alzheimer’s. However, the gene for Chlolesteryl Ester Transfer Protein (CETP) has been identified as a possible new contributor to the genetic risk factor. In order to test this association we obtained data on over 4000 subjects studied in the Cache County Study on Memory, Health and Aging over a 15-year period. This data included DNA samples, cognitive decline rates and incidence of dementia–particularly Alzheimer’s Disease. DNA samples were SNP genotyped using quantitative PCR. The SNP genotypes and corresponding phenotypes for each subject were then analyzed for association usingmixed linear models and for survival, or the amount of time until the disease appeared, using Cox proportional hazard models. We found a correlation between the V405I SNP and a decreased rate of cognitive decline. We found that for each additional G the rate of decline decreased by 0.6 points per year on the MMSE test. The identification of CETP as a player in the genetic risk for Alzheimer’s and dementia will provide much needed information on the genetic factors involved in dementia and allow for possible future therapeutic targets.

Modified Nucleosomes and the Effect on Positioning

January 01, 2013 12:00 AM
Tara Hammond, Brigham Young University Microbiology and Molecular Biology Genetic diseases, including Alzheimer’s, cystic fibrosis, and many cancers, can be detrimental to individuals and their families. Gene therapy can possibly cure these diseases by inserting a correct copy of the gene into the chromosome, upregulating good genes, or downregulating the harmful gene. When DNA is packaged into a cell, it wraps around histones-an octamer made up of two tetramers, each containing four different subunits to create nucleosomes. Where the nucleosome sits on the DNA sequence determines whether or not a gene can be transcribed. In heterochromatin, nucleosomes are denser and DNA is tightly packed, thus causing genes to not be transcribed. Euchromatin contains looser packed nucleosomes and therefore has higher transcription levels. This project seeks to determine if modified nucleosomes have DNA sequence preferences. We are working with histone H3 to tri-methylate lysine 4, which has been shown to correlate with euchromatin. The modified histone will be used to create octamers. C. elegans DNA will be added to modified histones and to unmodified histones and allowed to create nucleosomes. The wrapped DNA will be sequenced, allowing us to compare the modified and unmodified nucleosome DNA preference. The difference in preference will enhance our ability to know how to move nucleosomes, thus aiding in gene therapy.

Impact of Ungulate Browsing on the Development and Resilience of Aspen Forests

January 01, 2013 12:00 AM
Christian Boekweg, Brigham Young University Plant and Wildlife Sciences It has been shown that the population densities of deer and elk in the Rocky Mountains are at an unprecedented high. The heavy browsing of said species (ungulates) on regenerating aspen suckers can be devastating, leading to homogenously aged aspen stands that now have reduced resilience to drought, fire or logging disturbance, and an increased susceptibility to pathogens. Lastly, the extensive, highly selective herbivory of the aspen suckers may cause a shift in forest composition away from the aspen tree to an increase in other, less palatable species. We selected 186 sites across the 3 national forests of Central and Southern Utah, and characterized stand composition using the point quarter method. Stands were defined by successional stages from early to late; aspen, mixed or conifer. We then used pellet counts to estimate animal density and evaluated the effect of animal density and stand type on the regeneration success of aspen suckers. The key result of our study is that high ungulate density is highly correlated with reduced sucker heights (p<0.001). This indicates that high ungulate density impedes aspen regeneration by preventing aspen from recruiting into the overstory. Our study suggests that closer monitoring of the long term effects of herbivory on aspen development and regeneration is necessary to ensure vigorous aspen forests.