Filter and Sort







BIOL2023REGAN26425 BIOL

Investigating the Potential Therapeutic Effects of CBD In Vitro

Type: Undergraduate
Author(s): Allison Regan Biology Morgan Bertrand Biology Gary Boehm Psychology Paige Braden Kuhle Biology Michael Chumley Biology Alia Hannon Biology Vivienne Lacy Biology Chelsy Mani Biology
Advisor(s): Michael Chumley Biology Gary Boehm Psychology
Location: Second Floor, Table 4, Position 2, 11:30-1:30

Alzheimer’s disease (AD), currently the seventh leading cause of death in the United States, is a neurodegenerative disease characterized by amyloid beta (Aβ) plaques and chronic inflammation in the brain. Microglial cells, which act as the immune cells of the central nervous system (CNS), function in response to Aβ by secreting pro-inflammatory cytokines and reactive oxygen species (ROS). Microglial activation is a healthy response in the brain, but chronic activation of these cells and thus chronic secretion of neurotoxic factors creates a cyclic process that leads to neuronal cell death. In order to protect against oxidative stress, cells activate the nuclear factor erythroid 2-related factor (Nrf2) pathway. Nrf2 is a transcription factor that regulates the expression of antioxidant enzymes, which can protect the cell from ROS. Here we focus on the therapeutic potential of cannabidiol (CBD) to mitigate oxidative stress in both microglial and peripheral macrophage cell lines. We show that CBD can activate the Nrf2 pathway and thus increases the expression of several antioxidant proteins such as Heme oxygenase-1 (HO-1). This research is significant because it could provide evidence for the use of CBD as a potential therapy in AD patients.

View Presentation

BIOL2023SHEEHAN38439 BIOL

Effects of calcium on the survival of the invasive zebra mussel (Dreissena polymorpha).

Type: Undergraduate
Author(s): Ainsley Sheehan Biology
Advisor(s): Michael Misamore Biology
Location: Basement, Table 4, Position 2, 11:30-1:30

Zebra mussels are an introduced species that has spread throughout much of the eastern United States and recently invaded Texas. These freshwater mussels cause ecological damage by reducing food available and outcompeting native clams. They cause significant economic damage by attaching to hard surfaces in the water such as pipes to factories and water treatment plants. Understanding where they might spread is an important step in controlling their invasion. Predicting their distribution can be challenging; however, several factors are indicative of where zebra mussels may spread (pH levels, temperature, calcium). Of these factors, calcium is currently viewed as the most significant. Zebra mussels needing calcium for general blood physiology, creating their calcium carbonate shells, and by developing larvae which have small shells. The working model is that zebra mussels will thrive in waters with calcium levels greater than 27mg/L, zebra mussel adults may survive but the larvae may not survive in calcium levels between 27-12 mg/L, and less than 12mg/L of calcium is too low for any stage of mussels to survive for an extended period. My projected look at survival of zebra mussels at varying concentrations of calcium in waters on zebra mussels. Differing calcium levels of 0, 5, 10, 20, and 30 mg/L in artificial pondwater were be used to determine at what levels of calcium zebra mussels are able to survive.

View Presentation

BIOL2023SIMMONS30354 BIOL

Characterizing the role of a hypothetical protein in the pathogenesis of Cryptococcus neoformans

Type: Undergraduate
Author(s): Morgan Simmons Biology Natalia Castro Lopez Biology Floyd Wormley Biology
Advisor(s): Floyd Wormley Biology Natalia Castro Lopez Biology
Location: Second Floor, Table 6, Position 3, 1:45-3:45

Cryptococcus neorformans is a fungal pathogen that mainly affects immunocompromised patients and is opportunistic as it invades the central nervous system. In the Wormley research lab, we are currently working with multiple genes that have been shown to be involved in lipid metabolism. C. neorformans. Using the TRACE procedure; Transient CRISPR-Cas9 coupled with Electroporation is hypothesized to be a reliable method in order to knock out genes in C. neoformans. This specific project we have been working on will lead to a knockout by using CRISPR methodology to create a Cryptococcus neoforman deletion construct for an associated gene. We are analyzing identified genes that have been found to be upregulated in C. neoformans, multiple of which have been shown to be involved in lipid metabolism and virulence. By characterizing the role of these genes and certain proteins this project aims to deepen the knowledge of the roles of lipids in pathogenesis and hopefully develop ways to combat infection of people with weakened immune systems. To further characterize the role of these genes in virulence we focus on the gene CNAG_00474, which was upregulated in C. neoformans in the presence of arachidonic acid. To achieve this we will generate a KO using the TRACE technique. The overall problem in this study is the implications these fungal proteins may have and the lack of understanding surrounding their involvement which is essential to research in order to create a pathway leading toward potential drug targets. The methodology of this project includes the amplifying promoter and end sequences from the unidentified protein to fuse the primer with sgRNA to create a construct ultimately. From here, amplifying the ‘arms’ of the target protein and the selection marker from a plasmid (in this case NAT) will use PCR to fuse the marker and arms together and create the deletion construct. Once we confirm the gene has been knocked out we will analyze its role in virulence by assessing phenotypic characteristics in vitro and in vivo. I am hoping in the near future to have the specific KO ready to be able to confirm it via PCR.

View Presentation

BIOL2023SOLOMONS32321 BIOL

Innovations in marine toxicity testing: Fish embryo and mysid tests as replacements for larval test

Type: Undergraduate
Author(s): Katie Solomons Biology
Advisor(s): Marlo Jeffries Biology
Location: Basement, Table 3, Position 2, 11:30-1:30

Marine environments are at risk of contamination from oil refinery effluents, major oil spills, and wastewater runoff. To identify and mitigate such risks, the EPA requires toxicity testing of marine effluents. The larval growth and survival (LGS) test, featuring either sheepshead minnows (SHMs) or inland silversides (INS), is currently used to screen marine effluents for acute toxicity; however, the use of fish larvae represents an animal welfare concern, especially in light of legislation calling for adherence to the 3Rs of animal research. The fish embryo toxicity (FET) test and mysid growth and survival (MGS) test may represent viable alternatives to LGS tests as the FET test uses fish embryos (which are thought to experience less pain than older fish), while the MGS test uses invertebrates. The objective of this study was to determine if the FET and/or the MGS tests produce similar results as the LGS. To accomplish this, INS LGS, SHM LGS, INS FET, SHM FET, and MGS tests were run using phenanthrene, an environmentally-relevant component of crude oil. Results revealed that the LC50 values obtained from the MGS and INS LGS tests were comparable and that both were significantly lower than that of the other test types, suggesting that the MGS test may be a viable replacement for the LGS tests. This was further substantiated when growth metrics were evaluated. In contrast, the LC50 values obtained from both FET tests were significantly higher than those of the other test types indicating a relative lack of sensitivity. However, when hatchability was included as a test metric, the sensitivity of the INS and SHM FET was enhanced indicating that the inclusion of hatch may improve FET test performance.

View Presentation

BIOL2023STRANG30700 BIOL

Watershed Mapping of the Thule Defense Zone - Northwest Greenland

Type: Graduate
Author(s): Benjamin Strang Biology
Advisor(s): Matt Chumchal Biology
Location: Basement, Table 6, Position 2, 1:45-3:45

The Thule Defense Zone in Northwest Greenland is a region of ecological concern because of its sensitive Arctic tundra ecosystem. Anthropogenic-induced climate change and deposition of contaminants into these fragile systems has the potential to alter these ecosystems. Mercury is a toxin of global importance that is capable of contaminating landscapes far from its source of origin, including those in the high Arctic. Understanding levels of mercury contamination that persist across landscapes requires analysis of aquatic ecosystems, as these systems are where mercury is converted into its toxic form, methylmercury. In Summer 2023, the Aquatic Ecology Lab at Texas Christian University will be traveling to the Thule Defense Zone and testing six ponds for mercury contamination. To better understand how contaminants reach these ponds, nutrient inputs from the landscape need to be understood. To date, there is no available watershed map for the Thule Defense Zone that delineates the hydrological characteristics of these ponds. My project will use Geographic Information Systems (GIS) to create a formal delineation of these aquatic systems.

View Presentation

BIOL2023TAMAYO64218 BIOL

Taxonomic Re-evaluation of the Tropical Blueberries (Vaccinium L., Ericaceae) of Palawan and Mindanao Islands, Philippines

Type: Graduate
Author(s): Maverick Tamayo Biology Peter Fritsch Biology John Horner Biology
Advisor(s): John Horner Biology
Location: Second Floor, Table 6, Position 2, 1:45-3:45

Biodiversity, which is important to the function and stability of ecosystems, is currently being lost to extinction at an alarming rate. Thus, cataloguing and documenting the biodiversity of the world has never been more critical. In this study, the diversity and taxonomy of the tropical blueberries (Vaccinium L., Ericaceae) of Palawan and Mindanao Islands, Philippines were revisited. A total of 27 species (24 from Mindanao and four from Palawan) were documented and recorded. Six novel species, four new island records, and clarification of three ambiguous species complexes were included. Two of the six novel species (V. jubatum and V. vomicum) were discovered among historical herbarium collections, while the rest (V. carmesinum, V. coarctatum, V. fallax, and V. gamay) were discovered during botanical excursions. Two previously island endemic blueberries, V. cebuense and V. banksii, were documented to have an extended distribution in Mindanao. Additionally, V. irigaense is also recorded in Mindanao, whereas V. pseudocaudatum is recorded for the flora of Palawan. Further, the V. barandanum, V. caudatum, and V. halconense species complexes were taxonomically explained. The nomenclatural status of these species was stabilized through assigning type specimens following specifications of the International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code). We concluded that Mindanao Island is the center of Philippine Vaccinium diversity. This study underscores the crucial role of herbaria in understanding the floristic diversity of the world. This study also serves as a basis for taxonomical studies of the other blueberries in the Philippine Islands and Southeast Asia.

View Presentation

BIOL2023VANDYCK37697 BIOL

The Effects of a Mediterranean Versus Western Diet in C57BL/6J Mice on Inflammation in the Brain

Type: Undergraduate
Author(s): Emily Van Dyck Biology Gary Boehm Psychology Paige Braden Kuhle Psychology Kelly Brice Psychology Michael Chumley Biology Catherine Shoffner Biology Buse Uras Psychology
Advisor(s): Michael Chumley Biology
Location: Basement, Table 3, Position 1, 1:45-3:45

Due to our rapidly aging population, 6.5 million Americans currently have Alzheimer’s disease (AD), and this is predicted to increase to almost 14 million in the next 40 years. AD is more prevalent in western societies, and researchers suggest that this may be due to the typical Western diet. In contrast, AD prevalence is lower in Mediterranean regions, where a healthier diet could be a contributing factor. Therefore, this research examined the neuroprotective potential of a Mediterranean diet against AD pathologies and inflammation in mice. Our lab designed two experimental rodent diets, one that mimicked a typical Western-style diet, and another that mimicked a typical Mediterranean diet. We examined the lifelong effects of diet on biological markers of AD, including amyloid beta, a protein that aggregates together to form plaques in the AD brain, and pro-inflammatory cytokines, which are associated with increased inflammation. We hypothesized that the Mediterranean diet has the potential to mitigate these AD pathologies and therefore, could potentially be used as a future preventative strategy for AD.

View Presentation

BIOL2023WAITE19401 BIOL

Regulatory effects of loss of ClpX on the msrA chromosomal gene in Bacillus anthracis

Type: Undergraduate
Author(s): Kelsey Waite Biology Voung Do Biology Salina Hona Biology Shauna M. McGillivray Biology
Advisor(s): Shauna M. McGillivray Biology
Location: Basement, Table 11, Position 2, 11:30-1:30

Bacillus anthracis is the causative agent of anthrax. Previously, our lab identified the clpX gene as critical for virulence in B. anthracis. The ΔclpX mutant exhibited decreased cell wall integrity and increased susceptibility to cell-envelope active antibiotics. ClpX is one component of the intracellular caseinolytic protease ClpXP that degrades multiple proteins including transcriptional regulators. To understand changes in gene expression in ΔclpX, a microarray comparing WT and ΔclpX was conducted. This project focuses on msrA, an upregulated gene in ΔclpX. MsrA is an antioxidant enzyme that reduces methionine-S-sulfoxide to methionine but also impacts cell wall strength in S. aureus. This study will determine if loss of the msrA gene impacts antibiotic susceptibility. We hypothesized that since ΔmsrA is upregulated in ΔclpX, ΔmsrA would exhibit the opposite phenotype. Surprisingly, we find that ΔmsrA has significant growth inhibition in the presence of penicillin. However, we do not find susceptibility with other antibiotics, such as daptomycin, nor does it appear to be more susceptible to other clpX-related stress responses such as heat or acid stress. Future research will test ΔmsrA susceptibility to additional antimicrobials, such as the antimicrobial peptide LL-37 and the antibiotic vancomycin, as well as ΔmsrA virulence in vivo with the Galleria mellonella infection model. We will also complement ΔmsrA to confirm the phenotypes are due to loss of the msrA gene. This research is important as it aids our understanding of bacterial defenses and may provide new drug targets to help combat rising antibiotic resistance.

View Presentation

BIOL2023WHITMORE34464 BIOL

Mercury accumulation in spiders at the Great Salt Lake, Utah

Type: Graduate
Author(s): Kimberlee Whitmore Biology
Advisor(s): Matt Chumchal Biology
Location: Second Floor, Table 5, Position 1, 1:45-3:45

The Great Salt Lake in Utah is an important stopover point for many migratory bird species. Birds that stop to breed or forage at the Great Salt Lake may be at risk of mercury contamination due to high levels of methylmercury that are found in the lake. The purpose of this study was to examine the transfer of mercury from the lake into the terrestrial food web using organisms at the base of the food web. During the summers of 2019-2021 western spotted orb weaver spiders (Neoscona oaxacensis) and, when possible, brine flies (Ephydra sp.) were collected from various sites on Antelope Island. These specimens were analyzed for total mercury content using a Nippon MA-3000. In addition, satellite imagery and GIS software were used to document the approximate distance from the collection sites to the water surface. We examine differences between years, study sites and spider body size. We also examined the correlation between mercury levels and environmental conditions.

View Presentation

BIOL2023WILLINGHAM2013 BIOL

Effects of Preservation on Mercury Concentration in Spiders

Type: Undergraduate
Author(s): Macyn Willingham Biology
Advisor(s): Matt Chumchal Biology
Location: Third Floor, Table 4, Position 1, 1:45-3:45

Spiders are sentinel species, organisms that serve to map the bioavailable fraction of contaminants in an ecosystem by retaining their contaminants in their tissues. For example, spiders in the families Tetragnathidae and Araneidae are frequently used as sentinels of mercury contamination of aquatic ecosystems. Spiders are frequently preserved in alcohol prior to contaminant analysis but the impact of contamination on mercury concentrations in spiders has not been assessed. The objective of the present study was to determine the effects of different preservation methods on mercury concentrations in tissues of spiders in the families Tetragnathidae and Araneidae. The spiders were collected along water sources using nets and gloved hands. The Tetragnathids were collected from grassy terrain or a bridge overhanging the water of Lake Weatherford. The araneids were collected from a boat dock overhanging Eagle Mountain Lake. On site, each spider was placed into its respective bottle of varying ethanol or Ziplock's for freezing. Individual spiders were placed into one of three different concentrations of ethanol (100%, 95% , 70%) or frozen. Following about two months of preservation, the spiders were dried and run through the DMA-80 collecting the data for data analysis. Data xxxx *insert conclusion info*

View Presentation

BIOL2023WILSON1664 BIOL

Role of ClpX in the stress response and virulence of Bacillus anthracis: protease or chaperone?

Type: Undergraduate
Author(s): Lillian Wilson Biology Vuong Do Biology
Advisor(s): Shauna McGillivray Biology
Location: Third Floor, Table 5, Position 3, 1:45-3:45

Role of ClpX in the stress response and virulence of Bacillus anthracis: protease or chaperone?
Lillian Wilson, Vuong Do, S.M McGillivray
Department of Biology, Texas Christian University

Anthrax is a lethal infectious disease caused by the bacterial pathogen Bacillus anthracis. Our lab studies the virulence and antibiotic resistance of B. anthracis and we have identified a chromosomal gene clpX, as an important virulence factor, as its loss increases susceptibility to cell-envelope targeting antibiotics such as penicillin, daptomycin, and the antimicrobial peptide LL-37. ClpX is an ATPase that can act autonomously as a chaperone, or with a proteolytic core, ClpP, to degrade proteins. To investigate the mechanism ClpX uses, a plasmid pclpXI264E was designed with a mutation in clpX (I264E) that prevents ClpP binding and inhibits the formation of the ClpXP protease but does not disrupt the chaperone activity of ClpX. We used this to create 4 strains in the unencapsulated Sterne strain: wild-type and ∆clpX containing the empty inducible plasmid pUTE657, complementation plasmid with the non-mutated clpX gene (∆clpX + pclpX), and the mutated plasmid (∆clpX + pclpXI264E). Prior research done on these strains confirmed that ClpX relies on protease activity in antimicrobial stress; however, our goal was to assess its response in other environmental stressors such as acid stress, heat stress, and its virulence in vivo with the Galleria mellonella infection model. We find that that the protease activity of ClpX is important for all of these stresses. These results build on our earlier understanding and demonstrate that formation of the ClpXP protease is critical and any future development of drugs targeting the ClpX system should focus on protease formation rather than chaperone activity.

View Presentation

BIOL2023ZOLLINGER18403 BIOL

Understanding the Structure and Function of Protein Kinase C-epsilon using Site Directed Mutagenesis

Type: Undergraduate
Author(s): Mariana Zollinger Biology Dr. Giridhar Akkaraju Biology
Advisor(s): Giridhar Akkaraju Biology
Location: Second Floor, Table 2, Position 2, 11:30-1:30

This research is focused on gaining a better understanding of PKC-epsilon a calcium-dependent protein kinase involved in a wide range of cellular functions including cell proliferation, survival, and apoptosis. The interest in PKC-epsilon derives from the discovery of a de novo mutation in the PKC-epsilon gene in patients suffering from SHORT syndrome. This syndrome is a debilitating disorder characterized by short stature, hyperextensibility, ocular depression, Rieger anomaly, and teething decay. The project involved recapitulating the naturally occurring de novo mutation in vitro as well as determining if other mutations in PKC-epsilon could cause similar disease-state phenotypes. Using a technique known as Site Directed Mutagenesis mutations were introduced into the PKC-epsilon gene and the effects of these mutations on the protein expression were assessed. This mutational analysis will help identify the regions of PKC-epsilon that are vital for its function. This will help elucidate the effect of the same mutations in patients and could help predict the severity of disease. Obtaining a clearer picture of the different regions of the PKC-epsilon protein allows for future studies to focus on successfully fixing these regions when they become damaged and could therefore be used to help patients with SHORT syndrome.

View Presentation

PSYC2023BRICE15271 BIOL

8 hours a day keeps the doctor away: Effects of chronic sleep loss

Type: Graduate
Author(s): Kelly Brice Psychology Gary Boehm Psychology Paige Braden-Kuhle Psychology Michael Chumley Biology Vivienne Lacy Biology Chelsy Mani Biology Allison Regan Biology
Advisor(s): Gary Boehm Psychology Michael Chumley Biology
Location: Third Floor, Table 7, Position 1, 1:45-3:45

Healthy sleep is imperative for many biological and psychological functions, including immune function and neural plasticity. Alarmingly, over one-third of US adults report getting less than the minimum recommended 7 hours of sleep each night. Unfortunately, sleep loss is linked with impairments in immune and cognitive function. Our lab previously demonstrated that chronic sleep restriction (CSR) is associated with cognitive impairment in wild-type mice. The present research investigated the impact of CSR on markers of inflammation and neural plasticity in response to an immune insult in adult C57BL/6 mice. Male and female mice underwent six weeks of CSR, followed by one intraperitoneal injection of lipopolysaccharide (LPS) or saline. Four hours post-injection, serum and hippocampal tissue were collected for brain-derived neurotrophic factor (BDNF) and cytokine analysis. Results revealed patterns that differed between males and females. Male mice that underwent CSR and received LPS had increased serum pro- and anti-inflammatory cytokines, while cytokine mRNA in the hippocampus was decreased compared to control mice that received LPS. Conversely, female mice that underwent CSR and received LPS had decreased pro-inflammatory cytokines in both the serum and hippocampus compared to control mice that received LPS. Moreover, males that underwent CSR exhibited decreased hippocampal BDNF mRNA compared to controls, while this difference was not observed in females. These patterns of findings suggest a complicated interaction between chronic sleep loss, immune function, and sex, underscoring the necessity to understand how lifestyle factors such as sleep loss can influence immune and cognitive dysfunction in both men and women.

View Presentation

BIOL2022ABDALLA61047 BIOL

The Effect of Anti-inflammatory Compounds Involved in Alzheimer's Disease

Type: Undergraduate
Author(s): Ruwayd Abdalla Biology Giridhar Akkaraju Biology Prasad Gabbita Biology
Advisor(s): Giri Akkaraju Biology
Location: Basement, Table 3, Position 2, 1:45-3:45

Alzheimer’s Disease (AD) is the most common form of dementia that mainly impacts the brain, specifically inducing neuronal cell death in the central nervous system. AD is characterized by the secretion of the protein Tau, and the formation of plaques made up of Beta-amyloid protein. Tau and Beta-amyloid plaques activate the secretion of inflammatory cytokines by microglial cell. The resulting inflammation triggers neuronal cell death, which leads to damage and cognitive decline over time. The cytokines secreted by microglial cells activate the Nf-kB signaling pathway. Activation of Nf-kB results in gene expression and secretion of TNF-a, a cytokine known to be associated with inflammation. This leads to a feedback mechanism that results in greater inflammation.
Our lab has demonstrated that a variety of anti-inflammatory compounds derived from IDT (iso-indolin dithione), targets the Nf-kB pathway by reducing the levels of TNF-a at the protein/translational level. BV-2 cells, a mouse microglial cell line were used in this study. Inflammation was stimulated by exposing these cells to LPS to trigger the activation of the Nf-kB signaling pathway. We hypothesize that the drugs tested reduce levels of TNF-a secreted by BV-2 mouse microglial cells, and therefore, block the development of disease-associated CNS inflammation seen in Alzheimer’s disease

View Presentation

BIOL2022ADELEKE46088 BIOL

Identifying Novel Genes with Increased Susceptibility to Reactive Oxygen Species in Bacillus Anthracis Sterne

Type: Undergraduate
Author(s): Victoria Adeleke Biology Luke Hamilton Biology Shauna McGillivray Biology
Advisor(s): Shauna McGillivray Biology
Location: Second Floor, Table 1, Position 3, 1:45-3:45

Bacillus anthracis is a gram-positive bacterial pathogen that causes the deadly infectious disease anthrax. Bacillus anthracis contains two plasmids, pX01, and pX02. These plasmids were found to be necessary for the virulence of B. anthracis. However, Bacillus anthracis contains over 5,000 chromosomal genes and we believe that there are additional virulence genes that have yet to be discovered. Our lab constructed a transposon mutant library with random disruptions in the B. anthracis Sterne genome to screen for novel virulence factors. This library has been successfully used to identify the chromosomal genes clpX and yceGH and show their importance for B. anthracis virulence. To find additional novel virulence genes, we used the same transposon library and screened around 1,000 mutants using hydrogen peroxide, a reactive oxygen species (ROS). ROS are involved in the immune defense and the mutants that are attenuated in its presence may have a disrupted gene that contributes to the pathogenicity of B. anthracis. We obtained two mutants that were repeatedly susceptible to hydrogen peroxide in vitro. To determine the virulence of these mutants in an animal model, we will be performing an in vivo assay using the waxworm, Galleria Mellonella. Mutants that have reduced virulence in G. mellonella will be further tested to determine the location of the transposon in the genome to find out which genes are disrupted. The findings of this research could be used as potential therapeutic drug targets and could offer insight into the mechanisms that B. anthracis uses for its pathogenesis.

View Presentation

BIOL2022ALENIUSTHALHUBER12027 BIOL

Location and release method influence short-term reintroduction success of captive-bred hatchling Texas horned lizards (Phrynosoma cornutum).

Type: Graduate
Author(s): Rachel Alenius-Thalhuber Biology
Advisor(s): Dean Williams Biology
Location: Basement, Table 1, Position 2, 11:30-1:30

Reintroductions have become increasingly common to help restore populations of Texas horned lizards (Phrynosoma cornutum). Reintroduction success of any species can be shaped by many factors including genetics, selection of suitable reintroduction sites, etc. Our primary goal has been to determine whether release techniques- specifically site selection and release method- contribute to the reintroduction success of captive-bred hatchling Texas horned lizards. In 2020 and 2021, we reintroduced over 500 captive-bred hatchling Texas horned lizards from the Ft. Worth, Dallas, and Caldwell Zoos to Mason Mountain WMA (Mason County, TX). Lizards were randomly assigned to one of two release sites and were placed either in clumps of 20+ lizards (Site 2 2020 & Site 1 2021) or were dispersed 5 m from one another (Site 1 2020 & Site 2 2021) at release. We used harmonic radar to track lizards and monitor survivorship outcomes and growth rates from release (September or October) until most lizards began brumating in early December. We found that survival outcomes were associated with both release site (χ22, 509 = 34.5, p<0.0001) and release method (χ22, 509 =15.09, p=0.005). We achieved the highest survivorship (26.4%) when lizards were dispersed at Site 1. Preliminary dietary and prey availability assessments suggest that survivorship differences between locations may be related to differences in food availability. Our findings suggest that future reintroduction attempts may have higher success rates if 1) sites are selected that meet the specific resource requirements of hatchlings, and 2) lizards are dispersed from one another at release.

View Presentation

BIOL2022ALLENDER29315 BIOL

Mercury Accumulation in Wolf Spiders from the Clear Fork and West Fork of the Trinity River: Effect of Spider Sex and Body Size

Type: Undergraduate
Author(s): Christopher Allender Biology Robert Peterson Biology
Advisor(s): Matthew Chumchal Biology Ray Drenner Biology
Location: Second Floor, Table 8, Position 1, 1:45-3:45

Mercury (Hg) is released by coal-burning power plants and artisanal gold mines into the atmosphere. Mercury deposited from the atmosphere into aquatic ecosystems can be converted into a neurotoxic form, methyl mercury (MeHg). In aquatic ecosystems, Hg biomagnifies which can affect organisms feeding at higher trophic positions. However, monitoring Hg in the environment to assess the risk to biota is not straightforward. For example, measuring Hg in sediment may not reflect the amount of Hg bioaccumulating in organisms. This difference in the Hg in the sediment and the amount bioaccumulating is partly determined by the bioavailability of Hg. Measuring bioavailability is very complex so sentinels can be used to detect Hg in food chains. Sentinels are defined as organisms that accumulate Hg within their tissues without significant adverse effects. Riparian spiders have been proposed as sentinels. Riparian spiders eat emerging aquatic insects which transport Hg from aquatic ecosystems and because of this, riparian spiders are sentinels of aquatic Hg contamination. The objective of this study was to measure Hg levels in wolf spiders (family: Lycosidae). From May 2021- June 2021, spiders were collected at four sites, two on the Clear Fork and two on the West Fork of the Trinity River, and the spiders were preserved in 95% ethanol. The spiders were sorted based on sex and their body size was measured. Hg will be analyzed using direct mercury analysis. This study attempts to determine the effect of sex and body size on the amount of Hg in wolf spiders, factors that have not been assessed previously. It also attempts to detect differences in the concentration of Hg between the Clear Fork and the West Fork of the Trinity River.

View Presentation

BIOL2022BOWERS35745 BIOL

Testing the Ability of Macrocyclic Compounds to Reduce Reactive Oxygen Species (ROS)

Type: Undergraduate
Author(s): Cameron Bowers Biology Giridhar Akkaraju Biology Kayla Green Chemistry & Biochemistry Kristof Pota Chemistry & Biochemistry
Advisor(s): Giridhar Akkaraju Biology
Location: Second Floor, Table 2, Position 3, 11:30-1:30

In the pathogenesis of neurodegenerative inflammatory diseases, such as Alzheimer’s disease, there is an abnormal buildup of redox metal ions that associate with β-amyloid plaques and convert oxygen into oxygen radicals. These radicals are highly reactive with cellular components and lead to oxidative stress that induces damage and death of neuronal cells which is associated with the cognitive decline of Alzheimer’s disease. Bifunctional macrocyclic compounds with antioxidant properties are a promising potential therapeutic to reduce levels of reactive oxygen species (ROS) and increase neuronal cell survival via the ability to chelate dysregulated metal ions and radical scavenging. In this project, novel macrocyclic compounds were tested for their efficacy in reducing intracellular levels of H2O2-induced ROS and H2O2-induced cytotoxicity. Intracellular ROS levels and cell survival were quantified in FRDA and BV-2 cells using the DCFH-DA and MTT cytotoxicity assays.

View Presentation

BIOL2022BUSSARD55348 BIOL

Building a Better Mouse Trap: Novel Object Location vs Novel Object Recognition

Type: Undergraduate
Author(s): Morgan Bussard Biology Paige Braden-Kuhle Biology Kelly Brice Biology Claire Middleton Biology Shelby Kay Miller Biology
Advisor(s): Michael Chumley Biology Gary Boehm Psychology
Location: Third Floor, Table 2, Position 3, 1:45-3:45

Alzheimer’s disease (AD) is often associated with chronic inflammation and cognitive dysfunction. In studying how AD-like pathologies change and affect learning and memory, our lab aims to optimize an object location memory (OLM) testing paradigm in mice. Briefly, a mouse is placed into an arena with two identical objects for a training session. Four hours later, one of the objects is moved to a novel location, and the mouse is placed back into the arena for the testing session. Because mice exhibit a preference for novelty, memory is assessed as the amount of time the mouse spends exploring the moved object divided by the total time spent exploring both objects. Our goal is to identify testing parameters that make this task both accurate and efficient for our lab’s use, as we will add this learning paradigm to a battery of behavioral tests to be used in future experiments. In the current study, the OLM protocol will be performed twice according to two different experimental timelines that test the effects of adding an additional training session to the original protocol.

View Presentation

BIOL2022CASCELLA24290 BIOL

How important is enzymatic function? Determining which traits of the tumor suppressor BRCA1 rely on nucleosome ubiquitylation.

Type: Undergraduate
Author(s): Meenal Cascella Biology
Advisor(s): Mikaela Stewart Biology
Location: Basement, Table 12, Position 1, 1:45-3:45

BRCA1 is a gene found in humans that, when mutated, has been linked to breast and ovarian cancer. A homolog version of this gene, known as brc-1, exists in an organism called the Caenorhabditis elegans. This is a species of nematode worm that has the potential to be used as a model organism to study this homolog gene that is associated with human breast cancer. Previous studies with C. elegans have shown links between the brc-1 gene and DNA damage responses, cytochrome p450, or cyp, transcription levels, and ratios of male phenotype worms. This project focused on studying whether these brc-1 functions are dictated by the enzymatic activity of the protein made by this gene. To measure these phenotypes, we used a strain of C. elegans with a brc-1 mutation engineered to lack enzymatic activity of the BRCA1 protein toward nucleosomes. In order to determine how this lack of enzymatic activity affects brc-1 functions, we measured levels of reactive oxygen species (serving as a proxy for DNA damage), numbers of male offspring, and cyp levels in the mutant and wild-type C. elegans. Our initial results indicate the effects of enzymatic activity towards nucleosomes on the aforementioned phenotypes.

View Presentation

BIOL2022DO34325 BIOL

Investigating The Role of ClpX in Regulation of Stress Responses in Bacillus anthracis Sterne

Type: Graduate
Author(s): Vuong Do Biology
Advisor(s): Shauna McGillivray Biology
Location: Second Floor, Table 7, Position 1, 11:30-1:30

Anthrax is an infectious disease caused by Bacillus anthracis, which is a spore forming bacterium. Even though the anthrax toxins and capsule, encoded on 2 plasmids pXO1 and pXO2, play crucial role in the pathogenesis of anthrax infection, evidence suggests that chromosomal genes also play a role. The ClpX ATPase was discovered to be crucial for B. anthracis virulence via protection against host antimicrobial peptides. In this study, we want to investigate the role of clpX in regulation of other stressors including acidic stress, temperature stress, salt stress, and non-cell envelope active antibiotics. We found that clpX is necessary for survival in an acidic environment and growth under heat stress. We demonstrate that acidic stress resistance is mediated by the formation of the ClpXP protease using a ClpX complementation plasmid that is incapable of interacting with ClpP. There is no association between clpX with other stressors. We conclude that the ClpX is required for B. anthracis pathogenicity via defenses against host antimicrobial peptides and for survival in an acidic environment. Understanding the role ClpX in the regulation of stress responses will ultimately infer us with new target for either directly combating infection or improving the efficacy of already available medicines.

View Presentation

BIOL2022EASTBURN4625 BIOL

Impacts of Pollen Donor Distance and Nutrient Availability on Reproductive Success in a Carnivorous Plant

Type: Graduate
Author(s): Halia Eastburn Biology
Advisor(s): John Horner Biology
Location: Second Floor, Table 6, Position 3, 1:45-3:45

Impacts of Pollen-Donor Distance and Nutrient Availability on
Reproductive Success in a Carnivorous Plant

Halia Eastburn and John Horner

The maintenance of genetic diversity has important consequences for the survival of plant populations. Because plants are sessile, the distance between plants is often inversely correlated with relatedness. Therefore, the distance between pollen-donor and recipient can determine the level of inbreeding or outbreeding. Both pollen-donor distance and nutrient availability can affect reproductive success in populations of flowering plants. Populations of the carnivorous plant Sarracenia alata have dwindled and become extremely fragmented due to human development and agriculture. The purpose of this study was to examine the effects of pollen-donor distance and prey capture on reproductive success in S. alata. We hand-pollinated flowers with pollen from varying distances [0 m (self-pollinated) and 35, 60, 90, 125, and 190 m], and we prevented prey capture in half of our study plants. We measured seed production and germination to estimate reproductive success. Pollen-donors from greater distances sired a greater number of seeds but pollen-donor distance did not affect germinability. There was no effect of prey capture alone nor an interaction of pollen-donor and prey capture on seed production or germination. More research is needed to understand nutrient allocation for reproduction over multiple years and natural variance in prey capture which might affect reproductive output in subsequent seasons.

View Presentation

BIOL2022FALKENBERG44638 BIOL

Investigation of Conservation of BRD1 Activity in C. elegans

Type: Undergraduate
Author(s): Owen Falkenberg Biology
Advisor(s): Mikaela Stewart Biology
Location: First Floor, Table 6, Position 2, 11:30-1:30

Our project focused on the conservation of activity of the protein BRD1 in C. elegans. C. elegans is a strong model organism for our study because BRD-1 is the worm ortholog to BARD1 in humans. Specifically, our focus is on its function as an enzyme to attach ubiquitin to the H2A tail of nucleosomes. We studied a structural mutation of BRD-1 that we predicted would interfere with its ability to bind its substrate, the nucleosome. We hypothesized that BRD-1 is bound to the nucleosome at this mutation site based on prior research in the human protein. Therefore, we integrated mutations found in humans into the DNA that codes for C. elegans BRD-1. A typical mutagenesis protocol was used to implement the mutations and then we expressed the proteins in E. coli cells. After that, nucleosomes were reconstituted by dialysis, and enzyme activity was assessed using a ubiquitination assay. These assays showed that BRD-1 in C. elegans does bind the nucleosome demonstrating conservation of the BARD1 function. Determining that function is conserved allowed us to determine that C. elegans is an appropriate organism to test mutations found in humans. This research has future clinical potential due to the ability to test mutations encountered in humans using a model organism and can aid with clinical treatment plans to help avoid the development of cancer.

View Presentation

BIOL2022FARROLL62028 BIOL

Developing assays for testing the effectiveness of a TNF-alpha modulating Alzheimer’s drug

Type: Undergraduate
Author(s): Caroline Farroll Biology
Advisor(s): Giri Akkaraju Biology
Location: Second Floor, Table 3, Position 1, 1:45-3:45

Many anti-inflammatory drugs are currently in use to treat neuroinflammation in the brain which can result from Alzheimer's disease, Parkinson's disease, traumatic brain injury, and more. In collaboration with a company, P2Dbiosciences, we are testing drugs that can modulate the function of inflammatory cytokines such as TNF-alpha, with the goal of reducing neuroinflammation and thus benefiting people suffering from the neurodegeneration and cognitive decline associated with neuroinflammation. We hypothesize these drugs work by inhibiting the signaling associated with inflammatory cytokines.
Two different assays were developed to identify the mechanism of action of these cytokine modulating anti-inflammatory drugs. BV2 cells in culture were used for these assays to model how the drug affects mouse microglial cells (immune cells resident in the brain). The first assay uses a luciferase reporter gene to determine if NF-kB promoter activity is disrupted when cells are treated with drug. The second assay uses quantitative RT-PCR (qPCR) to measure changes in TNF-alpha mRNA levels when cells are treated with drug. Levels of TNF-alpha mRNA were also quantified over a period of time following drug treatment to determine whether the degradation time of the TNF-alpha mRNA was affected by treatment.

View Presentation

BIOL2022GARVEY17681 BIOL

THE NUMBER OF QUEENS IN RED INVASIVE FIRE ANT COLONIES AND TEXAS HORNED LIZARD DENSITY

Type: Undergraduate
Author(s): Jeffrey Garvey Biology
Advisor(s): Dean Williams Biology Marlo Jeffries Biology David Minter Chemistry & Biochemistry
Location: Second Floor, Table 9, Position 1, 1:45-3:45

Invasive species, such as the Red Imported Fire Ant (Solenopsis invicta, hereafter, RIFA), can negatively impact native species via predation and modifying prey behavior. RIFA exist in two colony types, monogyne (single queen) and polygyne (multiple queens), and polygyne colonies are known to contain higher densities of fire ants than monogyne colonies. Texas horned lizard (Phrynosoma cornutum) eggs and hatchlings are suspected prey of RIFA’s foraging and aggressive behaviors. In this study, we collected fire ants from Karnes City and Kenedy to determine if Texas horned lizard density is lower around polygyne colonies. We collected and sequenced 30 ants, of which 20 were RIFA. Counter to our expectations, there seemed to be no correlation between RIFA colony type and Texas horned lizard density. Furthermore, we found evidence that monogyne and polgyne colonies were coexisting. In future studies, we think larger sampling sizes and determining ratios of polygyne to monogyne colonies within the same area would be useful for further testing the hypothesis that colony type may affect horned lizard density.

View Presentation