Division I

Abstracts Submitted: Division I - Undergraduate students - Natural Sciences & Mathematics


Kestrel Research Project Along Interstate I-26

Brenda Castle and Fred Alsop. East Tennessee State University, Department of Biological Sciences

The goal of the Kestrel Undergraduate Project is to study the breeding success of the American Kestrel ( Falco sparverius) and to provide suitable nest boxes for the American Kestrel. The monitoring of the boxes is conducted to observe for signs of use and to count kestrel eggs and young. The hatchlings will be banded to see if the fledged falcons return to the boxes in the future. The current work being done on the project is to test the feathers of the American Kestrel to see what environmental implications are involved in the kestrels being located along Interstate I-26. Information from the literature review (see references) provides data from other studies showing the level of heavy metals detected in other bird species located along interstates and highways as well as polluted coastal areas. In addition, part of the goal of the Kestrel Project is to track the kestrel over long distances with the use of long range radio transmitters. Radio transmitters are currently being purchased for next spring’s hatchlings.


FUNCTIONAL CHARACTERIZATION OF A PUTATIVE FLAVONOID GLUCOSYLTRANSFERASE CLONED FROM GRAPEFRUIT ( CITRUS PARADISII) LEAVES

Jamie Cantrell, Lee M. Pike, and Cecilia McIntosh, Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37614

Flavonoids are an important group of plant chemicals with a wide variety of functions, including UV protection, protection against pathogens, regulation of plant fertility, germination and growth, flower and fruit coloration, and flavor properties such as the bitter grapefruit flavonoid, naringin. They also have antioxidant activity making them interesting from a health perspective. There are nine main flavonoid types made by a common “core” biosynthetic pathway. Due to additional modification reactions, over 5000 different flavonoids are produced in plants. The most common modification is glycosylation, transfer of a sugar moiety to a flavonoid, which makes flavonoids more soluble in water. Glucosyltransferases (GTs) are the enzymes responsible for adding glucoses. There are approximately eighty putative GT sequences in GENBANK, but only a few of them have been functionally characterized. Functional characterization of putative GTs requires that full length-clones be isolated, heterologously expressed, and the protein product biochemically characterized. Grapefruit seedlings were used as the model system from which to isolate GT clones due to their diverse flavonoid GT character. Obtaining clones of any grapefruit flavonoid GTs will be valuable, although previous efforts have focused on the flavanone-specific 7-O-GT (7GT) catalyzing the first step in converting naringenin to naringin. Previously, RNA was isolated from young grapefruit seedling leaves. Gene specific primers (GSPs) were designed from a conserved PSPG box region common to known GTs and used to amplify cDNA clones using the SMART RACE cDNA Amplification Kit. Using 5’ RACE PCR, 5’ends of several candidate GT sequences were found. Clone specific primers (CSPs) were designed to obtain 3’ends of clones using 3’ RACE PCR. Cloning, sequencing, and sequence analysis of PCR products was performed. Partial sequences were overlapped to obtain compiled sequences and additional primers designed in order to get full-length putative GT clones. C....


THE GENUS MORINDA IN THE GUIANAS: A TAXONOMIC TREATMENT AND PRELIMINARY STUDIES IN POLLEN MORPHOLOGY

Amanda Parks and Dr. Tim McDowell, Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37614

The plant genus Morinda is a found throughout the tropics and consists of approximately 80 species worldwide. This genus is of special interest because several of the species, such as M. citrifolia (noni), are widely used for their medicinal qualities. Ten of the 26 New World species are found in the region of the Guianas (Guyana, Surinam, and French Guiana) in South America, and these are the focus of my research. My project centers on the production of a taxonomic treatment and comprehensive dichotomous key for the Morinda species for the Flora of the Guianas, to be published in the volume on the Rubiaceae. Until now, there has been no taxonomic treatment for Morinda of this region. Requests for all available specimens of the Guiana species were made to seven of the largest herbaria worldwide. A list of morphological traits from all parts of the plants was developed and these traits were measured and described for each specimen. Over 400 herbarium specimens were studied, including the type collections (original collection) for each species. The original Latin diagnoses of each species were obtained and translated. These, as well as all other available descriptions for these species, were reviewed. New descriptions were composed for each species, including details of phenology (flowering and fruiting times), distribution and notes on similar species. In additional, a diagnostic key was completed for the 10 species recognized from the region. My treatment maintains, at the species level, all 10 species named from this region. However, two previously recognized subspecies of M. tenuiflora are not maintained in this treatment because morphological variation is continuous across these elements. The second part of my research will examine pollen morphology using light and scanning electron microscopy. Pollen will be extracted from the herbarium specimens of these and other New World Morinda species. Earlier studies suggest that most of the Guianan species of Morinda should be placed in ....


SPATIO-TEMPORAL DYNAMICS OF SOIL MOISTURE IN FORESTED WOODLOTS

Sara Nichols and Scott Peason, Department of Biology, Mars Hill College, Mars Hill, NC 28754

Soil moisture is one of the most important abiotic factors influencing the demography of populations and ecosystem processes. Spatio-temporal variation in percent moisture in the top 10 cm of soil was monitored in two woodlots during the summer and autumn of 2004. In each woodlot, measurements were taken at 10-m intervals within a 100 x 60 m sampling grid. We hypothesized that moisture levels would be correlated with precipitation, soil type & texture, and slope position. Moreover, soil texture should have the strongest influence. Temporal differences were correlated with precipitation and growing season. Differences in topography between the two woodlots accounted for among-site variation in the mean and variance of percent moisture. Low slope positions had higher variance in moisture in space and time than high slope positions. Spatial variation in soil moisture explains differences in the composition of vascular plant community across these sample grids.


DIVISION OF LABOR IN SOCIAL WASP COLONIES: AN AGENT-BASED APPROACH

Michael D. Phillips, Istvan Karsai, Department of Biological Sciences, and Jeff Knisley Department of Mathematics, East Tennessee State University, Johnson City, TN 37614

Social insect colonies develop into parallel processing systems in which the colony conducts most of its operations concurrently instead of sequentially. Recently, theories of self-organization have explained this behavior by using local information to provide a better understanding of the complexity and dynamics present in these systems. Social wasp colonies provide some of the clearest views of self-organization in biological systems. In particular, wasp nest construction provides a great opportunity to study division of labor. An ODE mathematical model of the division of labor in wasp colonies was developed by Karsai and Balazsi (2002). We build on this earlier work with a bottom-up modeling approach. To study the decentralized decision making in these colonies we propose an agent-based model that prohibits individual access to global information and ensures that all interactions take place on a local level. Using only a few simple mechanisms, we have created a model that accurately predicts the division of labor in social wasp colonies. With only a few simple behavioral rules and no central control present, the model is able to predict a great amount of complexity and capture the dynamics of the natural system.


Characteristics of Forest Stands Used for Nesting by Appalachian Yellow-bellied Sapsuckers.

Jared Bailey and Dr. Scott Pearson, Biology Department, Mars Hill College, Mars Hill, N.C.
 

The Appalachian Yellow-bellied Sapsucker (AppYBSA, Sphyrapicus varius) breeds in mid- to high-elevation forests in the mountains of Southern Blue Ridge Province. However, little quantitative information is available on the types of forest habitat it uses. This study compared the structure and composition of forest stands that contained AppYBSA nests to stands that did not harbor nests. Specifically, we compared the size and density of trees between nest and non-nest stands. At the stand level, there were no significant differences in tree size and density between nest and non-nest stands. However, AppYBSA preferred microsites with larger trees for the placement of nests compared to a random sample of available microsites in the surrounding forest. Over 75% of nests were found red maple ( Acer rubrum), sugar maple ( A. saccharum), or black locust ( Robinia pseudoacacia), and 75% of nest trees were >35 cm dbh. Observations on territorial behavior, spacing of nests, and bird behavior around the nests are also discussed.


A SINGLE LAYER FEED-FORWARD BACK-PROPAGATION NEURAL NETWORK

Patricia Carey and Jeff Knisley, Department of Mathematics, East Tennessee State University, College of Arts and Sciences, Johnson City, TN 37614

Diapause is an alternative state of development exhibited in many insects. This developmental state allows them to endure stressful environmental conditions, such as an impending winter. The flesh fly, Sarcophaga crassipalpis, enters the diapause state based on a circadian-gated response to extended night length. In this species, different genes appear to be active while the fly is in diapause. S. crassipalpis RNA and was hybridized against a Drosophila melanogaster gene set in a heterologous microarray. A single layer, feed-forward back-propagation artificial neural network has been trained on the heterologous microarray data. It was designed to test for candidate diapause-related genes and, eventually, to indicate genetic pathways for analysis and verification. We trained a single layer feed-forward neural network to microarray data. We also explored the consistency of a nonstandard firing function.


EFFECTS OF OXYCODONE ON FLESH FLY DEVELOPMENT

Jasmine Patterson and Dr. Karl Joplin, East Tennessee State University, Dept. of Biology, Johnson City, TN 37614

Insects play an important role in the process of decomposition. They are the first organisms to arrive after death and they colonize in a predictable sequence. Forensic entomologists use data collected about insect succession patterns observed in controlled experiments and compare this data to real cases to determine the time since death or post mortem interval. Since necrophagus insects feed directly on tissue from a cadaver, it is hypothesized they would ingest any toxic substances in those tissues. The present research shows what, if any, effect the presence of the drug oxycodone in tissues ingested by larvae has on the developmental rate of the larvae. In this experiment, three rats were given differing dosages of oxycodone with a fourth rat as a control. The rats were later sacrificed in a carbon dioxide chamber and their tissues were used as a food source for flesh fly larvae. The weight and length of larvae were recorded to detect any change in developmental rate caused by oxycodone. It was observed that the drug caused differences in weight and length in the larvae depending on the concentration in the tissues on which the larvae fed. Higher concentrations of oxycodone in the tissues ingested by larvae also caused a decrease in the percent emergence of adult flies from pupa. These results show a need for continuing studies of the effects of toxins on larvae of forensically important species. This data has significance in medico-criminal investigations because the post mortem interval could be inaccurately calculated by the use of insect succession patterns if the drugs found in the tissues ingested by larvae had an effect on their development and these drugs were not taken into account.


FUNCTIONAL AND MOLECULAR ANALYSIS OF THE WHITE GENE IN SARCOPHAGA CRASSIPALPIS

Robert G Morgan Jr, Dr. Hugh Miller III, and Dr. Karl Joplin, Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37614.

Sarcophaga crassipalpis is currently being studied due to the relative ease it takes to in-duce diapause. Diapause is an optional alternative life stage that is circadian gated. Dia-pause is controlled by genetic expression and is characterized by a temporary arrest of development at the pupal stage and a decrease in metabolic activity. In order to further understand the role of various genes in diapause, each must be studied from a molecular and functional perspective. To date, there has been no published papers giving a standard protocol for molecular of functional analysis in S. crassipalpis. We have selected to use the white gene that encodes for a product involved in the transport of pigment to the eye in order to both establish a standard protocol for analysis and have a phenotypic control. Thus far we have designed primers for the gene from known sequences of other related insect, obtained a gene fragment through RT-PCR, and verified the fragment through sequencing. The gene fragment shows good homology with the sequences used to design the primers and when run through a Blast search. Functional analysis is being done through RNAi with the results currently pending.


CHARACTERIZATION OF GENES DIFFERENTIALLY REGULATED IN SARCOPHAGA CRASSIPALPIS USING MICROARRAY ANALYSIS

Georganna Rosel, Karl Joplin, Hugh Miller III, Department of Biological Sciences, East Tennessee State University, Johnson City, TN 37614

Diapause is an alternative state of development exhibited in many insects. This inducible developmental state allows them to endure stressful environmental conditions, such as impending winter. The flesh fly, Sarcophaga crassipalpis, enters the diapause state based on a circadian-gated response to extended night length. Previous studies suggest that many genes are differentially regulated in the diapause developmental state. In our study, total RNA was isolated from S. crassipalpis and the cDNA probes were hybridized against a Drosophila melanogaster gene set in a heterologous microarray. The resulting values were normalized and candidate genes were selected based on the log2 values. The data suggests that there are approximately 350 up-regulated and 200 down-regulated genes. Bioinformatic analysis was used to design primers for a number of the candidate genes. Reverse transcription was performed using total RNA from diapausing and nondiapausing pupae and an oligo-dT primer. Candidate genes were amplified using PCR and visualized using agarose gel electrophoresis. The presence of a cDNA product in one state and not in the other was used as secondary verification of the state of the candidate gene. If the results were inconclusive, the process was repeated using gene-specific reverse primers in the reverse transcription. During the course of this research, bioinformatic analysis was conducted on 32 up-regulated and 36 down-regulated genes. These results allowed us to design for 6 up-regulated and 7 down-regulated genes. Of the seven status-verified genes, this work has resulted in three; desaturase is up-regulated while P38B and CG2246 are down-regulated. The verified genes are now being cloned and will be sent for sequencing. Results of this work were used to train a neural network in a parallel Institute of Quantitative Biology project. This work will further efforts to verify the microarray data and can be used in the future sequencing of the S. crassipalpis genome. Future research into the diapa....


THE RELATIONSHIP BETWEEN BETULA UBER AND BETULA LENTA

Joshua Belcher , Margie Tucker, and Kevin Jones, Department of Natural Sciences, University of Virginia’s College at Wise, Wise, VA 24293

Betula uber, the Virginia Round Leaf Birch, is a rare species of birch, characterized by circular leaves. Indigenous to Southwest Virginia, B. uber was the first woody plant to be placed on the Federal Endangered Species list. The true taxonomic status of this species has been ambiguous from the time of its discovery. We isolated DNA from B. uber and B. lenta, the Sweet Birch, and the Intervening Transcribed Spacer (ITS) regions of the DNA were amplified and sequenced. B. uber proved to be identical to B. lenta in the ITS region. Identity of these two trees’ sequences supports the argument that B. uber is a variety of B. lenta and does not warrant species status.