Department of Biology
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Item Age and growth of the white crappie, Pomoxis Annularis Rafinesque, in Lake Waco, Texas.(1969) Chen, Terry Huei-Hsiung; Lind, Owen T., 1934-; Baylor University.The major collection of white crappie was from 17 July 1967, to 10 April 1968, by traps and gill nets. Other fish were taken by anglers and seines in June 1968. A total of 1142 fish were included in this study. Spawning season for Lake Waco crappie was from late February to early May and was at its peak in March and April. White crappie in Lake Waco may spawn after one year. Growth rate of Lake Waco white crappie was rapid. The average back-calculated total lengths(TL) for Lake Waco crappie for the last 4 years were as follows: 145mm for the first year’s growth, 216mm for the second age group, 271mm for the third age group, and 309mm for the fourth age group. In the white crappie scales started to develop on the caudal peduncle in fish 16mmTL. The first fully scaled fish observed was 31mmTL. The region between the dorsal fin and pectoral fin was the last place to develop scales. The mathematical expression of the length-weight relationship for the white crappie of Lake Waco is: log W = -5.6131 + 3.2954 log L where W= body weight in grams L=total length in millimeters. The body-scale relationship demonstrated a parabolar curve. The equation L=35.506219 + 1.215665 S + 0.000931 s2 fitted the body-scale relationship of Lake Waco white crappie well. Principal food items of white crappie were small fishes (mainly shads, Dorosoma cepedianum and D. petenense), aquatic insects, and small crustaceans. Lymphocystis was only found in the spring, and about 1.7 percent of the fish were infected. Infection by nematode parasites, Camallanus oxycephalus, was observed in the spring and summer, but infected fish showed no signs of weakness.Item Bacterial growth on UV-B photolytically produced dissolved organic matter.(1995) Velarde, Gabriela; Lind, Owen T., 1934-; Baylor University.The effect of ultraviolet radiation into the Lake Chapala trophic processes was investigated in this study. Responses of bacterial populations to changes in UV radiation exposed water were significantly greater (bacterial biomass increased 57% and cell concentration increased 92%) compared to those populations that were grown in water covered by glass as UV blocker. Measurements for penetration of ultraviolet radiation in the water column of Lake Chapala were made at midday and to a depth of 0.45 m in one of the clearest parts ofthe lake (Station 11). Ten per cent of the UV radiation that reached the surface ofthe lake was still present at 0.2 m of depth. The extinction coefficient was 10.1 m. For a lake with low phytoplankton productivity, the supply of organic carbon via photolysis ofrefractory material may be an important supplement to bacteria in the water column.Item Biological nitrogen fixation in a nitrogen limited tropical lake, Lake Chapala, Mexico.(1987) Glass, Joan Ann; Lind, Owen T., 1934-; Baylor University.The objective of my study was to quantify the rate of biological nitrogen fixation in Lake Chapala, Mexico. Lake Chapala is the largest lake in Mexico. It is an ancient, tropical lake which is shaped in an east-west culde-sac with the inflow and outflow at the eastern end. Previous work showed low available nitrogen leading to nitrogen limitation of primary production. These measurements of available nitrogen ranged from undetectable to 1.8 _ - | mg 1 on an east-west gradient of sampling stations throughout the year. Nitrogen levels were lowest at the western end of the lake. Biological nitrogen fixation rates were expected to increase as the ambient nitrogen decreased. However, biological nitrogen fixation, measured by the acetylene reduction technique, was negligible at all stations. A reverse from the expected gradient of nitrogen fixation was found in the water from Lake Chapala when mixed with known nitrogen-fixing cyanobacteria. Greater nitrogen fixation by the added cyanobacteria was found with greater available nitrogen in the water. Also, the rate of nitrogen fixation by the introduced cyanobacteria increased when the water from Lake Chapala was filtered. This increased rate i i i of nitrogen fixation by the introduced cyanobacteria was attributed to the removal of an inhibitor within the water of Lake Chapala, Mexico. The lack of nitrogen fixation in Lake Chapala was attributed to the lack of filamentous cyanobacteria. There are three factors which may have inhibited the growth or functioning of cyanobacteria: 1) The high winds mixing this shallow lake inhibited growth of chains and mat formation of cyanobacteria. 2) Wind-induced turbidity contributed to light inhibition of cyanobacteria in the water column and sediments. 3) Organism on the suspended particulates or chemical compounds adsorbed to the suspended particulates may have been an inhibiting factor.Item Characterization of Hemicentin in C. elegans(2020-04-21) Ahumada, Abraham; Haworth, Emma; Ross, Kylie; Sowinski, Halee; Antony, Keerthi; Myeongwoo, Lee; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyCharacterization of Hemicentin in C. elegans Emma Haworth, Kylie Ross, Halee Sowinski, Keerthi Antony, Abraham Ahumada Department of Biology, Baylor University, One Bear Place 97388, Waco, TX 76798, U.S.A In the nematode, Caenorhabditis elegans, the him-4 gene linked to the X chromosome encodes hemicentin protein, a component of the extracellular matrix (ECM), which is characterized by 45 immunoglobulin repeats, and fibulin-like domains. The ECM is a three-dimensional network composed of proteins and sugars deposited outside of the cell. ECM proteins are typically large, glycosylated, and contain repeats and motifs for cell binding. Hemicentin is specifically present in the basement membrane (BM), a special sheet-like ECM, that plays an important role in cell migration and tissue attachment, and stability of mitotic germ cells. HIM-4 contains six RGD motifs, a protein sequence specific to the integrin binding receptor. In the following study, CRISPR gene editing was used to create mutations in him-4 at two of the six RGD sequences. These sequences were targeted to replace the D amino acid (Aspartic Acid) with the E amino acid (Glutamic Acid). This mutation in him-4 causes defective phenotypes related to cell binding. We have isolated several targeted animals with tissue fragility, suggesting that the RGD sequence is vital for the function of the protein; the gene editing may interfere with hemicentin binding to the integrin receptor. The disruption of the ECM causes improper attachment of the gonad BM to epithelial BM leading to the hemorrhaging of the gonads and the intestines in C. elegans. The observation of the hemorrhaging phenotype and the single-worm PCR will be used to detect CRISPR-induced homozygous alleles. This research may allow for further studies on gonad development and human orthologs of the hemicentin protein. The connection between the hemicentin protein and the ECM deformities may offer insight into diseases associated with tissue fragility.Item Effect of Cell Binding Domain Mutation in the unc-52 Gene of C. elegans(2020-04-21) Croomes, Olineece; Bertoluzzi, Siena; Johnson, Emily; Marquez, Meagan; Tajudeen, Mariam; Qiu, Zhonggiang; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyEmily Johnson, Morenike Tajudeen, Meagan Marquez, Siena Bertoluzzi, Olineece Croomes 7/31/2019 Effect of a cell binding domain mutation in the unc-52 gene of C. elegans Caenorhabditis elegans provides a significant canvas for research due to their sequenced genome, recorded molecular pathways, simple structure and comparative systematic components useful in modeling human diseases. The unc-52 gene in Caenorhabditis elegans encodes a homologouge for the extracellular matrix proteoglycan perlecan. UNC-52 constitutes a structural basement membrane protein which plays an important role in myofilament organization, and a regulator of growth-factor signaling in the body wall muscle cells. To determine the phenotypic effect formed from the presence of unc-52 mutation, we utilized the CRISPR-Cas9 gene-editing technology to mutate the amino acid sequence of the unc-52 gene. We edited the cell-binding domain of unc-52 and produced RGE (arg-gly-glu) from RGD (arg-gly-asp). We injected 52 N2 worms, and successfully generated several homozygous alleles in the C. elegans where the RGD sequences had been transformed to RGE. C. elegans was observed after treatment, and successfully mutated genes produced severely paralyzed uncoordinated worms in the surviving phenotype specimens proceeding CRISPR-cas 9 gene editing. Previous experiments with the unc-52 gene have shown a number of different mutations causing frameshift mutations and nonsense mutations which have been lethal to the organism. The RGD sequence we aim to mutate has been shown to mediate interactions with cell-surface integrins, as well as function in the development of myofilament lattice assembly. A severe phenotypic defect arising from the mutated genes would prove specifically the importance of the RGD sequence in the development of the cytoskeleton and cellular interactions, as well as demonstrate a non-lethal mutant in the unc-52 gene.Item The effect of clay minerals on cadmium toxicity to bacterial production.(1990) Balderson, Russell K.; Lind, Owen T., 1934-; Baylor University.The effect of clays on cadmium toxicity to bacterial production and specific production was investigated in Lake Brazos, McLennan County, Texas. Bacterial production calculated from ^H-thymidine incorporation rates in samples without added cadmium ranged from 5.3x10"^ to 2.13x10"^ jj.g c 1"1 hr~l. Specific production varied between 8.1x10"® and 3.32x10"4 (Ig C ^lg C"1 hr"*. Cadmium significantly reduced bacterial productivity at low levels (1 mg Cd 1"-*-) . The response was non-linear. Reduction ranged from 79% at 1 mg Cd 1"1 to 98.4% at 20 mg 1"1. Reduction at 5 and 10 mg Cd 1"^ was 62.4% and 65.1%, respectively. Specific production dropped by 70.5% at 1 mg Cd 1"1, 82.2% at 20 mg 1"-*-, 55% at 5 mg l"-'-, and 50.4% at 10 mg Cd 1"1. Added clays increased cadmium toxicity to bacteria. Bacterial production and specific productivity were reduced by 90.7% and 85.9%, respectively, at 1 mg Cd 1"1 in samples amended with 20 mg 1"^ clay. Cadmium toxicity decreased with further additions of clay, approaching that observed in the untreated samples.Item The Effect of Fertilizers on Methanotrophic Microbes in Wetland Environments(2022-05-09) Thompson, Pierce; Marty, Harvill; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyClimate Change is perhaps the greatest threat to life on Earth. As anthropogenic carbon emissions increase, the amount of methane released from wetlands increases. To combat large amounts of methane that are produced each day, organic pathways in organisms help regulate the levels of methane in biological ecosystems. However, usage of fertilizer in agriculture continues to stunt this naturally occurring regulation. To measure the effect that fertilizer has on methanotrophic microbes in a wetland environment, methanotrophic methane oxidation was monitored weekly. Soil was added to fourteen jars and fertilizer was added to half of those jars. The jars were incubated for a week before each measurement, emulating tropical wetland conditions; this allowed for more measurable results. Methane concentration was determined using a gas chromatographer (GC). The results showed that jars which contained fertilizer produced a significantly greater amount of methane (p=0.0072) compared to the control jars. These results can be used to better understand the effects of methane on an environment with high amounts of fertilizer runoff.Item The effect of the exotic cladoceran Daphnia lumholtzi on the native zooplankton of a central Texas reservoir.(1997) Fleming, Steven William; Lind, Owen T., 1934-; Baylor University.Waco reservoir was sampled for one year at five sample sites and six months at two sample sites in an attempt to detect competition between D. lumholtzi and native zooplankton. No competition could be detected. Also monitored were egg bank densities of D. lumholtzi, temperature of water, air and sediment. The seasonality and horizontal distribution of D. lumholtzi was also monitored for Waco reservoir for one year and was monitored in Belton Reservoir for four months. Although no strong correlation existed between D. lumholtzi and water temperature or Secchi depth in Waco reservoir, D. lumholtzi densities in Belton reservoir increased along a up-river transect including increasing water temperature, and reduced Secchi depth.Item The effect of the form and concentration of nitrogen on geosmin production by an aquatic actinomycete (streptomyces isolate WM1C1).(1983) Katzif, Samuel D.; Lind, Owen T., 1934-; Baylor University.Actinomycetes are organisms that produce geosmin which is one of the organic compounds responsible for the earthy (musty) odor in water. This study was designed to isolate an actinomycete, confirm it as a geosmin producer, and determine the effects of the form and concentration of nitrogen on the production of geosmin by the isolate. Five actinomycetes were isolated from the muds of Lake Waco; four were identified as Streptorayces and one as a possible Nocardia sp. or Micromonospora sp., and two Streptomyces spp. were confirmed to be geosmin producers by GC-MS. The effects of nitrogen on one Streptomyces sp. were reported as affecting threshold odor number (R.O.N.), biomass production (mg dry wt), and Specific T.O.N. (T.O.N.-mg dry wt ^). The forms of nitrogen used were NO^-N as KNO^, NH^-N as NH^Cl, and organic nitrogen (ORG-N) as asparagine and the concen- tration range of nitrogen was 0.000 mg'L to 0.600 mg * L. T.O.N. values increased linearly as concentrations of NO^-N and NH^-N increased while ORG-N (0.300 mg'L inhibited geosmin production. Biomass production increased linearly as concentrations of NO^-N and ORG-N increased (0.000 mg*L ^ to 0.600 mg'L"'*") but low concentrations of all three nitrogen forms did not promote significantly larger biomass proudction than the nitrogen-free media. Specific T.O.N. increased as concentrations of NH^-N and NO^-N increased with NH^-N producing significantly higher Specific T.O.N. per flask.Item Effects of Cuticle Mutagenesis on C. elegans Osmoregulatory Behavior(2020-04-21) Ramani, S.; Houston, A.; Odell, H.; Smock, V.; Spivey, F.; Williams, T.; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyThe cuticle of Caenorhabditis elegans plays a vital role in osmoregulation in stressed environments. While wild type C. elegans displays rapid deterioration in a hypertonic environment, certain mutant strains are hypothesized to elicit different responses to osmotic stress3. One such mutant is Dumpy (Dpy), which is characterized by a cuticle defect that produces short and fat worms with limited movement. The goal of this experiment was to analyze the effect of the Dpy mutation on osmoregulation by comparing the survivorship rates of N2 and Dpy strains of C. elegans when placed in a hypertonic environment. EMS mutagenesis was used to isolate populations of Dpy mutants, which were then exposed to .05 M, 0.1M, 0.25 M, 0.5 M, and 1.0 M NaCl for a 30 minute period. A survivorship assay was then conducted and results were compared to wild type survivorship within the different molarities. Dpy mutants were found to have consistently higher average rates of survival in higher molarity(>0.05M) solutions with a maximum difference of 4.2x in 0.5M. Further experimentation with this mutant can provide a molecular explanation of why the Dpy strain is able to resist more osmotic stress than N2 worms.Item Effects of Environmental pH Change on Wetland Microbial Communities(2020-04-21) Massingill, Emily K.; Le, Andy M.; Wimberly, Ally M.; Harvill, Marty; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyThe Waco Wetlands serves as a habitat to many different plant and animal species native to Waco while also acting as a source of bioremediation for the water flowing in from the North Bosque. Plants and microbes (such as bacteria) are responsible for filtering this water of unwanted chemicals. Bacterial proteins and enzymes perform best in certain pH conditions. Our objective is to find the optimal environmental pH for the Wetlands microbes. By finding the optimal environmental pH for these microbes, we can possibly, safely alter the pH of the Wetland water to make bioremediation by bacteria more efficient. The students will go about this by, first, obtaining pounds of soil samples and a few Liters of water from the Waco Wetlands. The Nitrogen Concentration and pH level of the Wetland water will be tested. Then, 5 different environments will be created in different containers (2 containers for each environment) varying in pH level. There will be a control environment with the pH of the Wetland water. There will be 2 different environments with a pH lower than the control and 2 with a pH higher than the control. Soil (containing microbes) will be added to each container and the Nitrogen level of each container will be tested. Record Nitrogen levels of each containers every week for the duration of the research project. The environments that showed the most drastic decrease in Nitrogen content will posses the optimal pH for these wetland microbes. This is due to the increased Nitrogen uptake by the bacteria and the increase in bacteria reproduction.Item Effects of Oxygen Concentration on Hemoglobin Analog Production in Chironomidae Larvae(2020-04-21) Sauer, Paige; Kumar, Devan; Wood, Zack; Harvill, Marty; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyThis experiment was conducted to test whether varying the oxygen content of a Chironomidae larvae’s environment would result in a color change of the larvae, signifying a change in hemoglobin analog concentration. Three environmental conditions were tested: a hypoxic environment, a high oxygen environment, and a control environment of open gas exchange. 100 larvae were placed in each environment and were left in their containers for five days. Results were recorded by crushing 20 of the specimens, diluting them in water, centrifuging the mixture, and measuring the absorbance of the solution in a spectrophotometer. The findings showed that the Chironomidae larvae from the high oxygen environment were in fact lighter than the others, and the larvae from the low oxygen environment were the darkest. This data supports the hypothesis that varied oxygen concentration results in color change in Chironomidae larvae.Item The effects of phosphorus starvation on phosphate storage, three storage products and cellular organelles of Chlorella pyrenoidosa.(1983) Ransom, Charlotte B.; Lind, Owen T., 1934-; Baylor University.The ultrastructure of phosphorus starved, phosphorus restored and total nutrient cells of Chlorella pyrenoidosa was described by i morphometric analysis. The rate of phosphorus incorporation into polyphosphate bodies of phosphorus starved cells was described as a volume fraction of the whole cell volume over a 210 min period. Maximum phosphorus incorporation into polyphosphate bodies of phosphorus starved cells occurred in the first 30 min of exposure to phosphorus. After 180 min exposure, the volume fraction of the polyphosphate bodie's of these cells decreased significantly. Several different trends were observed in the volume fractions of other cellular components. The volume fraction of starch in the chloroplast was significantly larger in the total nutrient cells than in cells of any other treatment. Lipids and pyrenoid volume fractions were significantly higher in phosphorus starved and phosphorus restored cells than in total nutrient cells. Phosphorus starved cells had the smallest volume fraction of vacuoles. Upon exposure to phosphorus, the vacuolar volume fraction increased until it equalled that of total nutrient cells. No significant differences in the volume fractions of the chloroplast, nucleus or mitochondrion were observed for any treatment.Item Genetic screening for suppressor mutation in Caenorhabditis elegans odr-3 mutants(2020-04-21) Carroll, Jacqueline; Badra, Anthony; Cantu, Analisa; Conway, Caitlyn; Diaz, Ashley; Gunderson, Annika; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyA suppressor mutation is a mutation that negates the effects of a different, separate mutation, facilitating a return to the wild-type phenotype. In this experiment, a suppressor mutation screen of a mutation of the odr-3 gene was conducted by observing the egg-laying behaviors of mutagenized Caenorhabditis elegans worms in different chemical stimulants, and comparing the results to the wild-type. A mutant with a successful suppressor mutation of an odr-3 mutation will have similar egg laying behaviors to that of the wild-type (N2). The gene, odr-3, encodes a G protein α subunit that plays an integral role in sensory and olfactory neurons. The role odr-3 plays is vital to olfactory sensation, osmoregulation, and mechanosensory function. In this experiment, two worm lines that each had an odr-3 mutation and a potential suppressor mutation were generated, isolated, and tested: odr-3-JC-17 and odr-3-JC-66. When serotonin was introduced, the odr-3-JC-17 mutant strain showed a similar response in egg laying compared to the wild type, N2. The average number of eggs laid in an hour for each of the N2, odr-3, odr-3-JC-17 and odr-3-JC-66 strains in serotonin solution were 0.18 0.33, 0.21, and 0.44 eggs/hour, respectively. In dopamine solution, odr-3-JC-17 demonstrated similar egg laying behavior to N2. In a dopamine solution, the N2, odr-3, odr-3-JC-17 and odr-3-JC-66 strains laid 1.04, 2.25, 1.29, and 0.40 eggs/hour, respectively. When placed in an imipramine solution, odr-3-JC-17 had a significantly higher value of eggs laid in an hour than the odr-3 mutant. In imipramine solution, the N2, odr-3, odr-3-JC-17, odr-3-JC-66 mutant strains laid 1.56, 1.53, 2.80, and 0.91 eggs/hour, respectively. These results indicate the presence of a suppressor mutation that is at least partially effective in the odr-3-JC-17 mutant strain.Item Genetic suppressor of che-3 serotonin response defects(2020-04-21) Kirsch, Lauren; Chaudhury, Tristin; Farlough, Catera; Gamayot, Jannine; Rodriguez, Grace; Weinberg, Savannah; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of Biologyche-3 is a cytosolic dynein heavy chain within Caenorhabditis elegans. This motor protein acts in intraflagellar transport and maintains structural integrity of sensory cilia structures. When mutated at the che-3 genetic locus, the mutants show progressive developmental defects of the chemosensory cilia. The che-3 mutants lose olfactory abilities and are unable to detect and respond to factors in their environment. Therefore, che-3 cannot respond to serotonin stimulation properly. Normally, wild type (N2) C. elegans produce more eggs in the presence of serotonin. Our goal was to test the relationship between serotonin and the olfactory senses within C.elegans. It is not known why che-3 is less responsive to serotonin. To address this, we mutagenized che-3 and found a suppressor that recovers the mutant’s response to serotonin. We created various trials to test a che-3 mutant suppressor that produces more eggs in the presence of serotonin than the wild type. The mutagenized che-3 were bred to yield the recessive F2 generation and placed in serotonin solutions to observe the number of eggs produced. The experiment was repeated many times to yield a consistent outcome. The results that were observed in che-3 mutants, compared to the wild type, produced more eggs in the presence of serotonin when the suppressing mutation occurred. In the future, further testing of che-3 mutants could aid in our understanding of the human response to serotonin and the effects of serotonin uptake within human chemosensory structures in the brain.Item Genetic suppressors of str-2 serotonin response defects in Caenorhabditis elegans(2020-04-21) Kumar, Amy; Gakhar, Shiv; Harris, Julian; Story, Shelby; Vo, Henry; Vo, Bill; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyC. elegans, a nematode, is a model organism to study animal behavior and development. The genome of the C. elegans shows that there is a similarity between the genes of the nematode and that of humans. C. elegans are widely used because of its rapid life cycle and its small size which makes it easy for laboratory cultivation. The str-2 gene in C. elegans is predicted to be responsible for receptor activity linked to olfactory responses. Through the binding of odorants on specific olfactory receptors, str-2 allows them to detect pheromones, environmental threats, and nutrition—essentially playing a vital role in their behavioral functioning. The egg-laying behavior of C. elegans is regulated by its surroundings and can be activated or inactivated through various environmental cues. However, without a properly functioning olfactory system, we hypothesize that C. elegans will be unable to initiate standard egg-laying activity through its inability to pick up on these environmental cues—even if they are in the presence of serotonin. In this study, we created a mutagenized str-2 C. elegans that was induced by ethyl methanesulfonate (EMS) which would also be resistant to the egg-laying ability response to serotonin. The C. elegans were treated and screened to ensure that they represented their ability to lay the least eggs in response to serotonin. Egg laying assays were repeated until the offspring was uniform. We found that in the life cycle of the the str-2 mutants were found have a decreased life cycle compared to the non-mutants. These mutants had crippled olfactory responses to environmental transmitters, and lacked sensory abilities that hindered life. In addition, we found that the number of offspring produced by the mutants were significantly less than those of the non-mutants.Item How does the material adsorbed onto flood-borne sediment affect lake zooplankton populations?(1997) Pittman, Helen M.; Lind, Owen T., 1934-; Baylor University.The effect of materials adsorbed onto flood-borne sediments on Brachionus calyciflorus was investigated in this study. Sediment samples were collected from the North Bosque River and South Bosque River which drain into Lake Waco for five months during flood events and low water flow. Measurements for population parameter changes were made after the rotifer cysts were subjected the materials leached off the floodborne sediment (elutriates). B. calyciflorus population growth and birth rates were inhibited and their death rates were stimulated when subjected to ambient elutriate concentrations containing contaminants from the North Bosque River. Population parameters remained statistically unaltered for the South Bosque River samples.Item Hypolimnetic oxygen decline and the hypolimnetic bacterial community.(1998) Rutherford, Kevin; Lind, Owen T., 1934-; Baylor University.This study reports on bacterial cell size and abundance change during oxygen depletion of Belton and Stillhouse Hollow reservoir. Bacterial cell size and abundance are compared with amount of heterotrophic nanoflagellates, dissolved oxygen, temperature, and time. The Relative Areal Hypolimnetic Oxygen Demand (RAHOD) was calculated for Belton and Stillhouse Hollow reservoir. Bacterial abundance in Belton and Stillhouse Hollow Reservoir was not greater than bacterial abundance in natural, northern lakes. Bacterial abundance's were not correlated with time, dissolved oxygen, temperature, and nanoflagellate abundance. Bacteria cell sizes in Belton and Stillhouse Hollow Reservoir were smaller than bacterial cell sizes in natural, northern lakes. Bacteria cell sizes were not correlated with temperature or nanoflagellate abundance. The RAHOD of Belton and Stillhouse Hollow Reservoir were lower than the RAHODs of natural northern lakes.Item Isolation of Mutant Caenorhabditis elegans Resistant to Integrin α Subunit Deficiency(2020-04-21) Johnson, Bryce; Battle, Rachel; Chavez, Boozaziel; Escamilla, Astrid; Smelser, Ashton; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyThe ina-1-encoded integrin α subunit is essential to Caenorhabditis elegans development, due to its role in complex processes such as morphogenesis, neuron migration, and cell signaling. Studies have shown that when this gene is mutated, many larvae die, and the worms that do survive display inactivity and morphogenic defects. Specifically, α-integrins function within heterodimeric integral membrane proteins and facilitate cellular and organismal processes via interactions between the cell’s cytoskeleton and other cell surfaces and the extracellular matrix. Similar to C. elegans’ ina-1 gene, humans possess 18 ina-1 homologs (ITGA3, ITGA6, and ITGA7), which are integral to normal human development; defects in the human α-integrin genes are linked to congenital muscular dystrophy, epidermolysis bullosa and cancer. C. elegans are a model organism to better understand integrin subunits and their important roles in both nematode development and human disorders due to their small number of α- integrin genes, which simplifies their genetic analysis. In this study, we generated and isolated mutants C. elegans that suppressed the integrin subunit deficiency by treating them with ethyl methanesulfonate (EMS). Mutants expressing suppressor mutations were characterized by more successful development, viability, and movement. The phenotypes were analyzed, and the mutants displaying these characteristics were isolated and cultured to form a colony of worms that contained the suppressor mutation. In the future, we will genetically analyze the suppressors of ina-1 mutations to elucidate their genetic basis and their important implications in human homologs.Item Isolation of the him-4 suppressor mutation which rescues the vitality of C. elegans(2020-04-21) Phipps, V.; Hartsfield, D.; Marsh, T.; Shalo, P.; Shields, B.; Lee, Myeongwoo; Baylor University. Dept. of Biology; Baylor University.; Baylor University. Dept. of BiologyThe nematode Caenorhabditis contains hemicentin, which is a protein that aids in gonad development, as well as tissue formation. The him-4 gene, associated with the production of hemicentin, was used to observe the effects of mutagenesis on C. elegans development and to isolate progeny that suppressed it. Five suppressors of him-4 (e1267) were isolated, and its phenotypes were compared to N2 (wild-type) and him-4. Phenotypic analyses revealed there had been a significant amount of suppression of the him-4 mutation. The results of the RNAi indicate some of the suppressors had an increased number of offspring when compared to him-4 mutants by the five suppressors. RNAi pat-3 and ina-1 indicated that some of the suppressors had an increased number of offspring when compared to the him-4 mutants. The overall results of the phenotypic assays, RNAi and hatch rates indicate some degree of suppression and seem to support the possibility of reversing the effects of him-4. Further research into the mechanisms of suppression and gene interaction, could result in significant information could then be applied to the human ortholog of hemicentin.