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Alterations in neurological development and/or vision have been noted after exposures to a variety of environmental contaminants, including heavy metals, pesticides, pharmaceuticals, and estrogens. Despite the growing interest in assessing the neurotoxicity of toxicants, routine toxicity testing methods do not currently include the assessment of endpoints capable of predicting adverse impacts on neurological development. A toxicity test featuring embryonic fathead minnows - the fish embryo toxicity (FET) test - was recently developed; however, it does not include neurological-related endpoints. Development of such endpoints would expand the utility of the FET test and allow for the assessment of neurological teratogens. Previous studies have identified embryonic eye size as a potential FET test endpoint, and though there is limited evidence suggesting that these alterations are indicative of altered neurological development, studies validating the link between eye size and organism fitness are needed. The overarching goal of this project is to investigate whether reduced embryonic eye size at the conclusion of the FET test is predicative of altered vision or neurological function in larval fathead minnows. But first, assays for assessing vision and neurological function in larval fathead minnows must be developed and/or validated. Therefore, the objective of the present study was to validate methods to assess vision/neurological function in larval fathead minnows. Three assays were developed: the optomotor response assay, a feeding assay, and the c-start assay. The ability of these assays to identify alterations in the neurological function of larval fathead minnows was assessed by exposing larvae to three doses of the known neurotoxicant chlorpyrifos for 5 or 12 d. These results will be utilized in future studies investigating whether reductions in embryonic eye size are predictive of sublethal adverse effects and can also be utilized by other researchers interested in assessing vision/neurological function in larval fathead minnows.
Bacillus anthracis is a Gram-positive bacterium that causes anthrax in humans. It is a significant microorganism in that many proteins important to virulence or pathogenesis are highly conserved in many other pathogenic bacteria. Our lab has previously identified the protein ClpX in Bacillus anthracis as metabolically significant in antibiotic resistance. Specifically, B. anthracis lacking the ClpX gene (ΔClpX) are significantly more susceptible to antibiotics that target the bacterial cell wall such as penicillin than the wild type. ClpX has multiple functions; primarily it interacts with ClpP to form a proteolytic complex that degrades dysfunctional or obsolete proteins. ClpX also has an independent chaperone function, moving proteins around the cell. This project has focused on determining if the pathway of decreased antibiotic resistance in mutant B. anthracis is dependent on ClpX interactions with ClpP, or if ClpX can function independently. To test this, a point mutation (I265E) was made in the ClpX gene at the site that has been previously identified as the site of interaction between ClpX and ClpP in Staphylococcus aureus. The ClpX genes in B. anthracis and S. aureus exhibit a high degree of conservation particularly in this region, and it is expected that this site will also be critical for ClpX and ClpP interaction in B. anthracis. The mutated ClpX gene (I265E) has been confirmed with sequencing and has been transformed as an inducible expression plasmit into the ΔClpX B. anthracis strain. The next step is to perfom growth assays in antibiotics such as penicillin to ascertain if the mutated expression vector can restore antibiotic resistance to ΔClpX.
Texas horned lizards Phrynosoma cornutum are a threatened species in the state of Texas, due to population declines and extinctions, especially in the eastern part of their range. Texas horned lizards are still found in small towns in south Texas and can reach densities that are much higher (~50 lizards/ha) than in natural areas (~4-10 lizards/ha). We used models of Texas horned lizards to test whether predation levels might be lower in two south Texas towns than on a ranch that was located in south Texas. We constructed Texas horned lizard models from urethane foam, a material that is ideal for preserving marks (bites and pecks) left behind by predators. Models (n = 126) were left in the field for a period of 9 days in each location and marks left behind by predators were categorized accordingly. We conducted this experiment in June and again in August 2018. We found significantly less attempted predation events in the towns (n = 1 predation attempt) compared to the ranch (n = 60) and no differences between months. Anecdotal observations over the past 6 years also support a lack of many horned lizard predators in the towns. Our results suggest that Texas horned lizards may be under heavy predation pressure in natural environments and that lizards living in urban areas may be escaping some of this pressure leading to higher than normal lizard densities in some small Texas towns.
The proper function of the Breast Cancer susceptibility gene 1 (BRCA1) and its subsequent protein in the human body is vital to healthy individuals. The malfunction of BRCA1 due to a mutation is associated with an increased risk of breast or ovarian cancer of up to 80%. The key to understanding whether a mutation in BRCA1 will lead to higher risk of cancer is its location. Many of its interactions with other proteins take place in the central region of BRCA1. Currently, little is known about how mutations located in this region affect BRCA1 structure and function. The central region is where BRCA1 interacts with another tumor suppressor called PALB2 to perform DNA repair. The central region site studied in this project can be activated as a response to DNA damage, influencing BRCA1 and PALB2 interaction to generate a damage repair response. We show how activation of BRCA1 affects its structure and function on the molecular level. The accomplish this we created three mutations in the central region that mimic activation of BRCA1 to identify possible significant changes in protein-protein interactions using biochemistry and structural biology techniques like Isothermal titration calorimetry and circular dichroism.
Author(s): Gabrielle Frediani Biology Kelly Brice Psychology Christopher Hagen Biology Briar Hill Psychology Sarah Nagel Biology Filza Qureshi Psychology Gabrielle Salinas Psychology
Advisor(s): Michael Chumley Biology Gary Boehm Psychology
Location: Session: 2; Basement; Table Number: 4
Alzheimer’s disease (AD) is a neurodegenerative disease resulting in dementia and memory impairment in patients. Research is immensely important as there are currently no treatments available to slow, prevent, or cure the damage inflicted upon individuals. The brain dysfunction in AD is marked by an increase in amyloid beta (Aβ), the protein responsible for plaque deposition in the brain. The severity of the cognitive deficits positively correlates with the load of Aβ. Prior research in animal models has pointed to Aβ causing synaptic disruption. A synapse is associated with information transfer inside the brain. Neuroscientists are trying to determine if the synapse disruption caused by Aβ leads to the cognitive dysfunction seen in AD. However, it is difficult it is to visualize individual neurons inside the hippocampus. In the present study, our aim was to understand the effect that Aβ has on synapses using an immunolabeling and tissue clearing technique in an AD transgenic mouse model. The 5xFAD mouse model utilized in this study rapidly develops Aβ pathology. This model mimics the pathophysiology of AD in humans. The mouse model used was also knock-in transgenic for Green Fluorescent Protein (GFP) on mature neurons. Using immunolabeling, GFP was tagged with antibodies, thus making neurons visible under the microscope. Antibodies were also used for Aβ in order to visualize the amount of Aβ protein and its location. Images of neurons were obtained in both FAD+/GFP+ and FAD-/GFP+ mice using a conventional staining method and a tissue clearing technique. We expected the tissue clearing technique, which clears lipids from the brain, to result in enhanced visualization of neurons but this was not the case. To quantify synapses, dendritic spines were counted on individual neurons in both groups of mice. Our results showed that Aβ accumulation in FAD+ mice correlates with a decreased number of dendritic spines signifying a decrease in synaptic density.
Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder that is currently ranked as the sixth leading cause of death in the United States. Those affected by the disease experience symptoms including but not limited to mental decline, memory loss, confusion, difficulty with language, and behavioral and mood changes. One of the hallmarks of AD is inflammation that occurs both centrally in the brain and in the periphery. While inflammation is the natural response to activation of our immune system and is critical for our survival, neuroinflammation is heavily associated with AD pathology. Two main cellular mediators involved with the inflammatory response are members of the glial cell family, microglial cells and astrocytes. When chronic inflammation is uncontrolled, it can lead to harmful cell and tissue damage. The continuous presence of damaged neurons results in the constant activation of microglia and astrocytes. This generates a neuroinflammatory environment which is thought to promote neurodegeneration. Another process commonly up regulated in the brains of aging individuals is that of oxidative stress, which plays a major role in age-related neurodegeneration and cognitive decline. The process can occur due to dysfunction of the antioxidant system, causing the accumulation of reactive oxygen species (ROS) in the brain. One of the primary biological markers of AD is the aggregation of Amyloid beta (Abeta). Abeta itself has been shown to act as a pro-inflammatory agent, promoting the activation of many inflammatory components. The accumulation of Abeta aggregates is thought to be exacerbated by essential biometal ions such as zinc and copper. Dr. Kayla Green’s lab in the TCU Chemistry Department has successfully created compounds that can simultaneously chelate metal ions and act as a powerful antioxidant. They have developed a family of compounds all consisting of N-heterocyclic amines that in turn, have the capacity to perform radical scavenging and metal ion capture. For the experimental design, BV2 neuronal cells were treated with either H202 or LPS for 16 hours. Following treatment, MTT assays were performed to measure cell viability. Once a treatment concentration was discovered that significantly decreased cell viability, varying concentrations of the N-heterocyclic amine were added to test for a recovery in overall cell viability.
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Exploring the Effects of Early Life Stage Nitrate Exposure on Sexual Development and Adult Reproduction
Nitrate is a ubiquitous environmental contaminant that enters aquatic ecosystems as runoff from agricultural fertilizers, human and animal waste, and industrial processes. Previous animal studies indicate that at sublethal concentrations, nitrate acts as an anti-androgen in adult male vertebrates. However, a recent study using developing fathead minnows (Pimephales promelas) found that exposure to nitrate was correlated with increased androgen concentrations. This study sought to reconcile these conflicting results by exploring the impacts of environmentally realistic, early life stage nitrate exposure on male sexual development and adult reproduction. The main objective of this study was to identify the potential endocrine disrupting effects of nitrate across multiple levels of biological organization in male fathead minnows. Larvae less than 1 day post hatch were divided into three groups: 1) control, 2) low nitrate (50 mg/L NO3), 3) high nitrate (100 mg/L NO3) and exposed for 35 days. Gonadal gene expression of sex-steroid related genes was assessed in a subset of fish immediately following exposure. The remaining fish in each exposure group were raised in clean water until sexual maturity (115 dph) and then subjected to a 21-day breeding study, after which morphological measurements and male secondary sex characteristics were assessed. Gene expression analysis revealed that male fish in the high nitrate group had significantly decreased expression of a key enzyme in the sex steroid synthesis pathway than that of the control males. Breeding pairs in the high nitrate group also had a significant reduction in average clutch size. However, when these results are taken in conjunction with the analyses of the other target genes, breeding study endpoints, and morphological measurements, the exact effects of nitrate on the processes of sexual development and adult reproduction remain unclear.
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Introduction: The purpose of this research was to determine differences in the effects of the sex hormone estrogen between the two genders on the endothelial function in vivo. Method: There was a total of forty-six college students from a liberal college in the South recruited. The forty-six students were twenty males and twenty-six females, who were divided into three groups: 20 males, 8 females (not taking any form of birth control) and 13 females (taking oral contraceptives). The participants were invited to complete a TCU approved IRB consent form and medical history questionnaire. Upon completion, the participants provided passive drool saliva for biomarker and sex hormone measurement and FMD for brachial artery flow and shear stress measurements. Results: Findings reveals that the mean age for males was 27.81 years and the mean age for females was 24.81 years. This data was found to be not significant (p = 0.0586). The BMI for males was 26.3 ± 3.59 kg/m2 and the BMI for females was 22.8 ± 2.36 kg/m2, found to be significant (p = 0.0003). 17-beta estradiol level was measured during follicular phase. There was no significant difference between men, women, and women on birth control. However, there was significant difference between male and female regarding nitrate production during the follicular phase (p = 0.0461). When comparing the post flow shear rate between women on birth control and women not on birth control, there was an increase in the shear velocity. Even though there was no significant change in sheer rate and FMD in the women on birth control, a trend toward an increase of both measures was noticed. Conclusion: There was found to be no significant difference in the effects of estrogen between men and women. Further research should be conducted to further specify the differences between women on contraceptives and men.
Author(s): Brian Niebuhr Biology Sophia Cosmich Biology Phat Do Biology Sarah Nagel Biology Caroline Wade Biology
Advisor(s): Matt Chumchal Biology
Location: Session: 1; Basement; Table Number: 2
In partnership with UT Southwestern Moncrief Cancer Institute (MCI), the FWAYA Oncology Coalition, and TCU Pre-Health, our dedicated group of senior students at Texas Christian University aim to organize an awareness week for Adolescents and Young Adults (AYA) with cancer during the national AYA Cancer awareness week (3/31-4/6) of spring 2019 to reach students on campus. The Moncrief Cancer Institute has a leading AYA cancer program, offering individualized treatment, support, and therapy at no cost for patients who have been diagnosed with cancer. AYA oncology refers to the care and research focused on adolescents and young adults diagnosed with cancer, specifically those between the age of 15 to 39 years old. Every year 80,000 AYA’s are diagnosed with cancer in the U.S, and 600 of these patients are living in and around Tarrant County. The goal of our project is two-fold. First, we seek to raise awareness for programs and resources available to AYA patients with cancer through a campus campaign. As many members of the Texas Christian University identify between the ages of 15 and 39, we believe this cause is pertinent to TCU’s population. Second, we seek to connect the TCU community with events hosted in DFW by UT Southwestern Moncrief Cancer Institute and the FWAYA Oncology Coalition. TCU AYA Cancer Week 2019 is an Experiential
Projects that Impact the Community (EPIC) Grant project.
Hepatitis C is a disease of the liver that is caused by the Hepatitis C virus. The Hepatitis C virus (HCV) chronically infects between 130-170 million people in the world making it a significant health burden. HCV is 9.6 kb single-stranded RNA virus and a member of the Flaviviridae family of viruses which includes viruses such as Zika and Dengue. It is a smaller virus with a mature virion size between 50-80 nm. With a specific tropism for liver cells, the diseases of Hepatitis C are accordingly associated with the liver. The two predominant diseases related to HCV infection are cirrhosis and hepatocellular carcinoma. These are both caused as a result of chronic infection which occurs in about 80% of cases as opposed to acute infection which composes only 20% of cases. In order to establish a chronic infection the virus has evolved the ability to inhibit the innate immune response leading to a greater likelihood of reproduction and survival. Our specific interest was the mechanism by which HCV evades the host immune response. In previous studies we have shown that NS5A 10A, a mutant protein of NS5A, inhibits the activation of the IFN-β promoter which serves a key role in the innate immune response. In this paper we investigate the specific mechanism of the ability of NS5A 10A to interfere with the activation of the IFN-β promoter.
Author(s): Dustin Rhoads Biology Dean Williams Biology
Advisor(s): Dean Williams Biology Sarah Hill Psychology John Horner Biology Laura Luque Biology
Location: Session: 2; 3rd Floor; Table Number: 8
Most of the literature on the basic ecology of Texas Horned Lizards cites "cryptic color pattern" as the first line of defense against predation in this taxon, and yet the degree to which horned lizards actually color-match their backgrounds has never been quantified. Texas zoos and state wildlife agencies are releasing captive-bred hatchlings and translocated adults to parts of their former range; however, the new populations are not self-sustaining, with the majority of releases lost to predation. Background color-matching has not been quantified for these reintroduction efforts but may be important to take into account when moving lizards into a new habitat where predation may be higher if they are not closely color-matched to the local soils. I quantify background color-matching in this taxon across its known range in the United States and in Mexico from in situ photos taken, as found, in the wild. I also present background color-matching variation and trends both within and between phenotypically and genetically diverse populations and ask whether lizards more closely match their local soil colors than soils from other areas. Finally, I suggest a method for zoos and wildlife agencies to score coloration in their captive populations of lizards, thus possibly enabling these institutions to objectively take into account color-matching a priori as an applied conservation strategy to potentially increase the survival of reintroduced Texas Horned Lizards.
Author(s): Alyssa Sanchez Biology Sara Gutierrez Cortazar Biology Carolyne Harvey Biology Heston Irons Biology Sohan Islam Biology Ashlyn Johns Biology
Advisor(s): Magnus Rittby Biology
Location: Session: 2; 2nd Floor; Table Number: 3
We are in the process of conducting a study on the effects of microgravity on Red Wiggler Earthworm decomposers. This experiment has been chosen for flight to the International Space Station to be conducted in the next several months. If we are to explore other planets in the future, we are hopeful that decomposers can grow and live successfully to bring the benefits that come with their existence. Ecosystems rely on decomposers as a building block to break down nutrients for plants. Decomposers are a critical part of an ecosystem. Earthworms play a role in in an ecosystem to constantly recycle broken down organic matter. With our experiment, we will gain more information about the growth of an Earthworm in microgravity. This experiment can help further space exploration to understand the effects of the microgravity on the growth of Earthworms.
Earthworms are crucial to the colonization of a planet due to being decomposers. They improve nutrients of the soil and they remove the dead roots, grass, and biotic factors by breaking them down. Breaking down organic matter to improve the fertility of the soil and create air pockets is such an important step in the process of decomposition. These air pockets are another benefit to the soil because it allows air flow through the soil. If we study the growth of the earthworm in microgravity, this could possibly help gain information in the process of growing produce and colonization on other celestial bodies in the future. This experiment will allow us to learn how a living organism reacts when it is growing and changing in microgravity. One part of this experiment is that we are going to compare the size of the earthworms grown in microgravity to the earthworm grown in Earth’s gravity. The growth size is a determining factor to whether earthworms are able to further space exploration and assist with the colonization of planet.
This experiment requires special handling during transportation to the International Space Station. We will be using a mini lab system provided called a Fluid Mixture Enclosure (FME) provided by the organization for the Student Spaceflights Experiment Program. This tube will be refrigerated from Burleson, TX. to NASA with a temperature of at least 40℉ or below. It will also need to be refrigerated on its return to Burleson, TX from NASA. We will follow the same experimental process with the control test on Earth.
Author(s): Alyssa Sanchez Biology Macie Davis Biology Olivia Earley Biology Alex Mercer Biology Ava Monroe Biology Itzel Perez Orozco Biology
Advisor(s): Magnus Rittby Biology
Location: Session: 2; 2nd Floor; Table Number: 3
We will be attempting to answer the question: What is the effect of microgravity vs gravity on the growth of a lentil bean? We chose this test subject to determine if lentil beans are a solution to help bone density issues and bone degeneration while astronauts are onboard the International Space Station.
While astronauts are in space, their bones degenerate and they lose muscle tone. Lentil beans can help bones and muscles develop as they contain calcium, magnesium, potassium, and protein. In our experiment, we hope to learn the effects of microgravity on plant growth ans to see if lentils grow the same in both environments. We can also use the information gathered from the lentils to conclude whether or not microgravity conditions are an adequate environment for farming and developing crops, which in turn will help determine if lentils are an appropriate crop to cultivate while on board the ISS.
Lentil beans are part of the legume family, which are usually inexpensive, nutritionally dense and a great source of protein. They are also a good source of calcium, magnesium, and potassium. Besides human consumption, lentil beans can be used for livestock feed too. In the agricultural context, the lentil beans can be utilized as a rotational crop with wheat. Lentil beans are a highly nutritious food, rich in minerals, protein, and fiber. Lentil beans are an economical source of protein, meaning it is affordable at a low-cost to prepare the beans. Lentil beans can be used as a supplement to a grain diet due to the high-protein and high-carbohydrate nutritional content.
Our hypothesis is that lentil beans will grow faster in space since there is a lesser amount of gravity in the ISS. Our experiment will help us understand how to better provide a sustainable food source for astronauts. Lentil beans, along with exercising, will allow their bones and muscles to stay strong and healthy in a microgravity environment. With our collected data after the experiment, the science community will understand how the effects of microgravity have on the growth of the lentil bean. If we explore and further understand the growth effects in microgravity of a lentil bean, this will allow us to seek deeper into understanding how other useful plants will grow in microgravity. This study will add to the research that has already been conducted. This experimental test is crucial to analyze the adjustments or changes that might need to occur to continue the legacy of the lentil bean in microgravity.
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Indigo Buntings (Passerina cyanea) and Painted Buntings (Passerina ciris) are closely related songbirds in the family Cardinalidae, found to co-exist in areas where ranges overlap. However, though both species share similarities in morphology, diet and preferred habitat characteristics, there is little quantitative data accumulated about the Painted Bunting and many aspects of its life history remain unclear. North American Breeding Bird Surveys have shown a significant decline in Painted Bunting population numbers across their ranges—a decline that has resulted in its designation of a Species of Special Concern by Partners in Flight. Proposed reasons for the decline include habitat destruction, sensitivity to disturbance and factors associated with decreased success in breeding. Within the Great Trinity Forest, the Indigo and Painted bunting’s breeding grounds overlap. The Great Trinity Forest is a large urban forest surrounded by the city limits of Dallas, TX containing a variety of disturbance factors characteristically associated with a highly urbanized area: poor habitat, invasive species, and increased noise and light. Sensitive species, such as the Painted Bunting, are typically found to avoid areas of disturbance. Data collected May-July 2018 shows presence/absence of both species within 140, 5 ha plots spanning the forest. Additional disturbance data was collected, including noise levels (db), invasive wild hog activity and percent impervious surface both within and surrounding each study site. Analysis of this data will aid in discovering how these species distribute themselves in relation to disturbance factors, urbanization and each other. Results will further serve to assist in future conservation efforts and increased life history knowledge of the painted bunting. It is predicted that disturbance factors within the Great Trinity Forest have a significant effect on Painted Bunting presence/absence while they have no significant effect on the Indigo Bunting.
Large numbers of bats are killed at wind energy facilities world-wide and there is a pressing need to improve our understanding of why this is happening and develop effective strategies to minimize impacts. Although Texas has more installed wind energy than any other state in the U.S., there are very few publicly available data about bat mortality at Texas wind farms. This is especially true of areas that are only recently seeing wind energy development, such as far south Texas in the Rio Grande River Valley. A couple of reports suggest that northern yellow bats (Lasiurus intermedius) and southern yellow bats (Lasiurus ega) may frequently be killed at these wind energy facilities, but we know very little about population sex ratios or population structure in these two species. In collaboration with a researcher at Texas State University, San Marcos, we have extracted DNA from tissue samples taken from 88 northern yellow bats and 64 southern yellow bats killed at wind farms in Starr and Hidalgo Counties. First, we used a genetic method, in which we amplified regions of the X and Y chromosomes using PCR, to determine the sex of the bat carcasses. Next, we used a DNA barcoding approach to assess the accuracy of species identification in the field. These efforts represent the first steps in a study to evaluate genetic diversity and population structure in two species of yellow bats that will likely be negatively impacted by wind energy development.
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Methylmercury (MeHg) is an environmental contaminate that has harmful effects on
wildlife. Anthropogenic sources like coal mining emit inorganic mercury (Hg) into the
atmosphere. From the atmosphere, Hg is deposited into aquatic ecosystems. Once in aquatic
ecosystems, inorganic Hg is converted to MeHg by bacteria and enters the food web. Emergent
aquatic insects (e.g. dragonflies), insects with aquatic larval stages and terrestrial adult stages,
will transport MeHg from the aquatic ecosystem to terrestrial predators like songbirds.
This project focuses on MeHg contamination of nestling Red-winged blackbirds
(Agelaius phoeniceus) from nests at the Eagle Mountain Hatchery Pond Facility. It is believed
that nestling Red-winged blackbirds (RWBL) consume aquatic-based prey, primarily odonates
(damselflies and dragonflies) but can consume terrestrial prey as well. Odonates are known to
have high levels of MeHg contamination. Although studies have attempted to observe what
RWBL parents feed nestlings, there are no studies of the actual prey composition in the
nestlings’ digestive tracts. Insects consumed by birds can be analyzed because external coverings
of insect body parts (head capsules, mandibles, legs) are composed of undigestible chiton. This study looks at nestling RWBL diets to quantify odonates in their diets. We will sort through varying fecal samples from the Pond Facility in order to determine the diet composition of the RWBL, and if the composition correlates with MeHg levels in nestlings.
In many patients with breast cancer, a mutation in their BRCA1 gene disrupts BRCA1 protein’s function as a tumor suppressor. One mechanism through which BRCA1 prevents cancer is by acting as an enzyme to attach a signaling protein called ubiquitin to a H2A, a DNA packaging protein. This attachment inhibits gene expression of DNA damaging proteins. Here, we determine whether enzymatic activity of BRCA1 towards H2A is a conserved feature in C. elegans, a microscopic worm used as a model organism.
To measure conservation, we used mutagenesis to introduce mutations into C. elegans’ BRCA1 at a region homologous to the known human H2A binding site. Similar to mutations at this site in human BRCA1, our results showed a decrease in enzymatic activity when mutations were present. This indicates that C. elegans BRCA1 and human BRCA1 use similar mechanisms of attachment to H2A. To develop tools to study this reaction in C. elegans, we need to understand the position on H2A to which ubiquitin is attached. To accomplish this, we generated C. elegans H2A using cloning to eventually determine the specific location of ubiquitin attachment.
Our experiment is about diabetes and Human and synthetic insulin crystallization in a microgravity environment. This experiment is designed to help us find out if there is a way to prevent crystallization of insulin, especially if we understand how it happens in microgravity. When insulin crystallizes, the bacteria that usually makes it viable stops working. This would cause it to be ineffective for patients in dire need of this medication. To complete this experiment we would like to send three different varieties of insulin in a type 3 mini lab FME (Fluids Mixture Enclosure) to the International Space Station (ISS), kept in ambient temperatures, to see if it crystallization occurs within a certain amount of time. We will keep the experiment refrigerated at or below 40℉ during transportation to the ISS and again after arrival back to our lab to prevent crystallization occurring outside of the experiment. Refrigeration slows the crystallization growth and this is how it is stored on Earth. Keeping our experiment refrigerated during transportation is an important step because the insulin crystallization growth should only be measured while in microgravity. It is also important to note that crystallization of insulin is slow so change in crystal growth will not be evident if out of refrigeration for short periods of time. We would like to keep our insulin types out of refrigeration for a period of six weeks minimum. While testing insulin crystallization in microgravity, we will be conducting the same experiment on Earth as our control. If we can understand more about synthetic insulin, maybe one day diabetic men and women can follow their passion of being astronauts and humans with this disease will have the opportunity to go to microgravity environments for extended periods of time.
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Hepatitis C virus currently infects around 130-170 million people. HCV, a member of the Flaviviridae family, causes chronic liver inflammation which can lead to liver cirrhosis or hepatocellular carcinoma. One of the nonstructural proteins of HCV, NS5A, is known to diminish the host innate immune response via inhibition of antiviral gene expression. NS5A blocks NFkB from entering the nucleus, decreasing transcription of IFN-B. Specifically, NS5A 10A, a mutant form of the protein, is known to greatly diminish the activity of the IFN B promoter. Our goal is to determine how WT NS5A and another mutant, NS5A H27, affect this pathway as well. We did this by transfecting HEK 293 cells with the NS5A mutant of interest, infecting the cells with Sendai virus, and subsequently measuring the activity of the IFN B promoter using a luciferase assay. In addition, NS5A contains three domains: I, II, and III. We are interested in determining which domain of NS5A is particularly important for blocking antiviral gene expression. We designed primers to created truncations of the protein containing the individual domains via PCR.
Author(s): Thomas Thalhuber Biology Matthew Chumchal Biology Ray Drenner Biology William Zudock Biology
Advisor(s): Matthew Chumchal Biology Ray Drenner Biology
Location: Session: 2; 2nd Floor; Table Number: 7
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Red-winged blackbirds (Agelaius phoeniceus) are found throughout North America, often nesting in cattails in ponds and wetlands. Diet studies have revealed that adults can feed their nestlings both emergent aquatic insects like odonates and terrestrial insects like lepidopteran larvae. Because emergent aquatic insects can be contaminated with high amounts of methyl mercury (MeHg), it has been hypothesized that nestlings fed high amount of odonates would be contaminated with levels of MeHg that are hazardous to their health. There have been no of studies of MeHg contamination of nestling Red-winged blackbirds and their diet. The objective of our study was to measure the concentration of MeHg in blood of nestling Red-winged blackbird and to estimate the proportion of emergent aquatic insects and terrestrial insects in their diet. We conducted a study of Red-winged blackbird nestlings at 20 ponds at the Eagle Mountain Fish Hatchery, Fort Worth, Texas. The ponds are contaminated with Hg from the atmosphere. Previous studies at the Hatchery have demonstrated that emergent aquatic insects such as odonates have high concentrations of MeHg while terrestrial insects on the pond shorelines have low concentrations of MeHg. Red-winged blackbirds nested in cattails in the ponds from April 9 to July 30 2017. We collected 424 blood samples from 243 nestlings from 88 nests (1-2 samples from 1-4 nestlings per nest). We analyzed the blood for MeHg, and analyzed 202 of the blood samples (1-2 blood samples from 1 per nest) for nitrogen stable isotopes. Methyl mercury was detected in nestling blood suggesting that Red-winged blackbird nestlings were fed emergent aquatic insects. However, concentrations of MeHg in nestling blood were low (mean of 0.020 ug/g ww) and below the risk threshold. Methyl mercury concentrations and nitrogen stable isotope ratios for Red-winged blackbird nestlings suggest that terrestrial insects composed a high proportion of their diets. Our study suggests that Red-winged blackbird nestlings may not be at risk of MeHg contamination when terrestrial organisms dominate their diet.
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Previous studies showed that exposures to thyroid inhibitors during early stages of development lead to long-lasting alterations in disease resistance. Therefore, the goal of this project was to assess the effects of early life stages thyroid disruption on the maturation and function of immune cells using propylthiouracil (PTU)-exposed fathead minnow as a model system. The specific objectives of this study were to evaluate the impacts of early life stage PTU-exposure on 1) neutrophil migration and 2) transcriptomic markers of lymphoid and myeloid cell development. These objectives were accomplished by exposing fathead minnow embryos to 35 mg/L and 70 mg/L PTU for 10 days, while evaluating neutrophils migration with a tail nicking assay and assessing immune cell development by measuring transcriptomic markers of maturation at 10 days post fertilization (dpf). There were no differences in transcriptomic markers for lymphoid cell development between PTU and control groups. However, PTU-exposed larvae showed a decreased amount of neutrophils at wound site as well as decreased v-ymb expression compared to those of the control at days 7 and 10, indicating that early life stage thyroid disruption interfered with the normal development and subsequently reduced immune response in these organisms.
Purpose: The objective of this retrospective study was to identify genetic variants of gene encoding a major drug-metabolizing enzyme among two different races – African American and Caucasian – based on pharmacogenomics testing and interpretive report (GeneSight). The study might shed lights for the application of precision prescribing in the clinical settings in the near future.
Methods: A retrospective study of de-identified interpretive reports from GeneSight of sixteen individuals (n = 16) at the Mental health Mental Retardation (MHMR) of Tarrant County. There are five reports of male and eleven reports of female in this study, of which six are African American and ten are Caucasians. The study was divided into two groups based on their races. Percentage of different alleles within variants of the CYP gene family were determined. Based on genetic components of patients, drug recommendations were made by AsureRx Healh, Inc.
Hypotheses: CYP2 is known to be highly polymorphic in the scientific literature. It is hypothesized that genetic variants will be observed in the CYP2 gene.
Cancer is one of the leading causes of death in the United States and is predicted to directly affect 38% of the population over the course of their life. Cancer is categorized as a collection of diseases primarily characterized by aberrant cellular proliferation. Many current cancer therapies, such as chemotherapy, do not differentiate between cancer cells and normal cells resulting in a variety of negative side effects. In an attempt to minimize these side effects, there has been a huge impetus to develop targeted therapies, which exploit cancer-specific molecules to exhibit selective toxicity towards cancer cells. For example, the monoclonal antibody Trastuzumab (Herceptin) targets the Human Epidermal Growth Factor Receptor 2 (HER2) that is overexpressed in some breast cancer cells. Another cancer-specific molecule overexpressed in some breast cancers, as well as cervical cancers, is the receptor for biotin. Biotin, more commonly known as Vitamin B7, functions intracellularly as an important coenzyme for several carboxylase enzymes involved in fatty acid synthesis, amino acid metabolism and gluconeogenesis. Thus, by overexpressing the biotin receptor some cancers increase their overall absorption of biotin resulting in a higher metabolic and proliferation rate. Furthermore, the high metabolic rate in cancer leads these cells to have increased to damage by reactive oxygen species (ROS) which can trigger apoptosis at high intracellular levels. Therefore, our project is exploring this overexpression of the biotin receptor as a potential avenue for targeted therapy against certain breast cancers. Ferrocene is an organometallic compound with an iron-center that has been shown to generate ROS in cancer cells. Since certain breast cancers overexpress the biotin receptor and absorb biotin with a higher efficiency, we hypothesize that conjugating biotin to ferrocene will increase the efficiency of ferrocene entering cancer cells, resulting in selective toxicity. Therefore, we have produced a library of biotin-ferrocene conjugates to test their ability to selectively enter cancer cells and generate ROS. Experiments were conducted utilizing ferrocene and a variety of conjugates (C1, C2, C3, 2) in both cancer (MCF-7) and non-cancer cells (HEK293).
(Presentation is private)
Endocrine disrupting compounds (EDCs) interfere with hormone production and action. EDCs typically mimic native hormones and often have a similar structure to natural hormones. While previous animal studies suggest that nitrate alters the synthesis of testosterone, nitrate is different than typical EDCs as its structure is not similar to that of any naturally occurring hormones. Given this and the environmental prevalence of nitrate, the objectives of this study are to 1) determine if nitrate acts as an EDC and 2) to better understand the mechanisms and effects of nitrate exposures on hormone production and reproduction. To achieve these objectives, groups of sexually mature adult fathead minnows were exposed to nitrate for 28 days. On days 7 and 28 of the exposure period, minnows were sacrificed for the collection of blood and gonads. The blood was used to evaluate hormone levels, while the gonads were used for gene expression analysis. Additionally, during the exposure, endpoints indicative of reproductive capabilities were also evaluated. There were no significant differences between exposure groups regarding gene expression, and there were no dose-dependent differences in egg production over the course of the breeding study.
(Presentation is private)
Floral herbivory (florivory) can have direct effects on both female and male reproductive output. Damage to flower parts such as petals and anthers can also have potential indirect effects by altering floral attractiveness to pollinators. Because carnivorous plants live in nutrient-poor environments and have slow growth rates, these plants may be at increased risk of negative effects of florivory. However, there has been no study to investigate florivory in carnivorous plants. We conducted a two-year field study on an east-central Texas population of the carnivorous pitcher plant Sarracenia alata and its specialist herbivore Exyra semicrocea. Populations were surveyed for number of flowers attacked, and the mass of floral components was compared between attacked and unattacked flowers. In 2017, a mean of 65% of flowers were attacked at the end of the flowering season. Based on mass before dehiscence, the mass of anthers after florivory was 49.5% of unattacked anthers. There were no significant differences in the masses of other floral structures at the end of the season. In 2018, 38% of flowers surveyed were attacked. The mass of attacked ovaries was 47% that of unattacked, the mass of sepals and petals combined was 62.5% that of unattacked, and the stigma/style complex was 51.0% that of unattacked. The mass of attacked anthers before dehiscence was 18.7% that of unattacked anthers. This study shows that there was annual variation in both the proportion of flowers attacked in the population, and the extent of damage seen in floral structures. Future studies should examine the effects of florivory on pollen limitation, pollinator behavior, and recruitment in Sarracenia alata.