Life Sciences Commons^™

Comparison Between Listeria Sensu Stricto And Listeria Sensu Lato Strains Identifies Novel Determinants Involved In Infection, Jakob Schardt, Grant Jones, Stefanie Müller-Herbst, Kristina Schauer, Sarah E. F. D'Orazio, Thilo M. Fuchs

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The human pathogen L. monocytogenes and the animal pathogen L. ivanovii, together with four other species isolated from symptom-free animals, form the "Listeria sensu stricto" clade. The members of the second clade, "Listeria sensu lato", are believed to be solely environmental bacteria without the ability to colonize mammalian hosts. To identify novel determinants that contribute to infection by L. monocytogenes, the causative agent of the foodborne disease listeriosis, we performed a genome comparison of the two clades and found 151 candidate genes that are conserved in the Listeria sensu stricto species. Two factors were …

Unseen Science: Modern Discoveries Too Far Away Or Tiny For Human Eyes, Lucy Huang

Capstones

As science has progressed, scientists have realized that evidence goes beyond the realms of physical sight. Whether it is too small or difficult to find, scientists have developed different ways to get around this problem. We see this in cancer genomics and in extrasolar planetary research. Scientists use what they know and what they measure to validate their work.

https://lucy-huang-9tge.squarespace.com/

Effects Of Crude Oil On Tumor Suppressor P53 Polymorphisms In Laboratory-Exposed Atlantic Killifish, Fundulus Heteroclitus, Allison Margaret Nadler

Seton Hall University Dissertations and Theses (ETDs)

Polycyclic aromatic hydrocarbons (PAHs), constituents of crude oil, are implicated as a potent source of adverse toxicological effects on living organisms. To model the effects of PAHs in response to environmental oil spill disasters a species of killifish (Fundulus heteroclitus) was captured and exposed to crude oil in a laboratory-controlled setting. Over a period of 7 days, fish were dosed with crude oil by gavage, culled, and organs were harvested for analysis. Excitation-emission matrix spectroscopy (EEMS) of gall bladder tissue homogenates was used to verify exposure. Effects of PAHs on the p53 gene were evaluated as an indicator …

Mechanistic Insights Into The Regulation Of Mitochondrial Fission By Cyclin C, Vidyaramanan Ganesan, Katrina F Cooper, Randy Strich

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Cyclin C is a component of the mediator complex of RNA polymerase II that localizes to the nucleus under normal conditions. In response to stress, cyclin C translocates to the cytosol and mitochondria and mediates stress‐induced mitochondrial fission and apoptosis. The molecular mechanisms by which cyclin C induces mitochondrial fission are unknown. Using in vitro experimental approaches, we sought to investigate the mechanistic basis of cyclin C mediated mitochondrial fission.

Mechanical Test Methods For Assessing Porcine Carotid And Uterine Artery Burst Pressure Following Ex Vivo Ultrasonic Ligature Seal And Transection, Carissa M. Krane, Margaret Pinnell, Courtney Gardner, Mercedes Thompson, James Coleman, Robert Wilkens

Robert J. Wilkens

A test method was developed to identify those variables important for assessing the performance of ultrasonic surgical devices in ex vivo ligature sealing of porcine carotid and uterine arteries. Ruggedness testing using a small sample size in pilot experiments was conducted using a newly developed test method in an effort to assess the usefulness of this methodology and to identify test variables that might warrant further testing. The development of this test method included the use of a custom-designed prototypic tension device for load-controlled ex vivo vessel stretching during saline perfusion and subsequent seal and transection of porcine arteries with …

A Neuroprotective Role For Mir-1017, A Non-Canonical Mirna, Matthew De Cruz

Master's Theses

miRNAs are post-transcriptional regulators of gene expression, with numerous being involved in neurobiology. Within the human genome a quarter of the identified miRNA loci derive from a class of miRNAs termed tailed mirtrons. Despite the identification of this large population of miRNA, no functional studies have been conducted to identify their role. In this study we examined the highly expressed and deeply conserved Drosophila 3’ tail mirtron, miR-1017, as a candidate to elucidate tailed mirtron functionality. We identified acetylcholine receptor transcripts, Da5 and Da2, as bona fide targets for miR-1017. Interestingly, Da2 is also the host transcript for miR-1017. We …

Stressing Out: Dynamics Of Chromatin Insulator Body Formation In Eukaryotes Under Osmotic Stress, Shannon Marie Garland

Masters Theses

Higher order genome organization and the role it plays in governing cell dynamics and protein expression has become a widely studied field. Chromatin insulators are important to this organization in their ability to form long range contacts between distant regions on the genome. During times of osmotic stress, insulator proteins leave their binding sites on the DNA to form insulator bodies in the nucleus. This phenomenon relieves the DNA of its structure and is rapidly reversible. Using a variety of immunofluorescent staining methods, this work looked to further characterize this process while attempting to identify molecular mechanisms that mediate chromatin …

Exploiting Fission Yeast Genetic Interaction Data To Identify Disease-Specific Drug Targets For Tuberous Sclerosis Complex, Ashyad Rayhan

Electronic Thesis and Dissertation Repository

Tuberous sclerosis complex (TSC) is an inherited genetic disorder caused by loss-of-function mutations in either TSC1 or TSC2. Their respective gene products regulate the mechanistic target of rapamycin (mTOR) signaling pathway, which serves as an activator of cellular proliferation, metabolism, and cell survival. Orthologs of the TSC1 and TSC2 genes exist in a wide range of organisms, including the commonly used and genetically tractable model eukaryote, Schizosaccharomyces pombe. To better understand the functional roles of S. pombe tsc1 and tsc2, I exploited recent advances in genetic interaction biology to identify and characterize genes that modulate the phenotypic …

Ablation Of An Ovarian Tumor Family Deubiquitinase Exposes The Underlying Regulation Governing The Plasticity Of Cell Cycle Progression In Toxoplasma Gondii, Animesh Dhara, Rodrigo De Paula Baptista, Jessica C. Kissinger, Ernest Charles Snow, Anthony P. Sinai

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The Toxoplasma genome encodes the capacity for distinct architectures underlying cell cycle progression in a life cycle stage-dependent manner. Replication in intermediate hosts occurs by endodyogeny, whereas a hybrid of schizogony and endopolygeny occurs in the gut of the definitive feline host. Here, we characterize the consequence of the loss of a cell cycle-regulated ovarian tumor (OTU family) deubiquitinase, OTUD3A of Toxoplasma gondii (TgOTUD3A; TGGT1_258780), in T. gondii tachyzoites. Rather than the mutation being detrimental, mutant parasites exhibited a fitness advantage, outcompeting the wild type. This phenotype was due to roughly one-third of TgOTUD3A-knockout (TgOTUD3A-KO) tachyzoites exhibiting deviations from endodyogeny …

Mechanism Of Transcription Anti-Termination In Human Mitochondria., Hauke S Hillen, Andrey V Parshin, Karen Agaronyan, Yaroslav I Morozov, James J Graber, Aleksandar Chernev, Kathrin Schwinghammer, Henning Urlaub, Michael Anikin, Patrick Cramer, Dmitry Temiakov

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

In human mitochondria, transcription termination events at a G-quadruplex region near the replication origin are thought to drive replication of mtDNA by generation of an RNA primer. This process is suppressed by a key regulator of mtDNA-the transcription factor TEFM. We determined the structure of an anti-termination complex in which TEFM is bound to transcribing mtRNAP. The structure reveals interactions of the dimeric pseudonuclease core of TEFM with mobile structural elements in mtRNAP and the nucleic acid components of the elongation complex (EC). Binding of TEFM to the DNA forms a downstream "sliding clamp," providing high processivity to the EC. …

An Undergraduate Laboratory Manual For Analyzing A Crispr Mutant With A Predicted Role In Regeneration, Susan Walsh, Ashley Becker, Paxton S. Sickler, Damian G. Clarke, Erin Jimenez

Faculty Publications

Exposing students to undergraduate research has reportedly improved students’ development of knowledge and skills in the laboratory, self-efficacy, satisfaction with their research, retention, and perseverance when faced with obstacles. Furthermore, utilizing authentic course-based undergraduate research experiences (CUREs) includes all students enrolled in the class, giving those who may not otherwise have access to an independent undergraduate research project an opportunity to engage in the scientific process in context of an original, unanswered question. In the fall of 2016, second semester introductory biology students conducted a semester-long research project on the transcription factor Lin28a to determine the effect of Lin28a on …

Jennifer Maurer Phd Thesis.Pdf, Jennifer Maurer

Jennifer Maurer

The Impact Of Co2-Related Ocean Acidification On The Molecular Regulation Of Shell Development In The Eastern Oyster (Crassostrea Virginica)., Mackenzie L. Richards

LSU Master's Theses

Eastern oysters (Crassostrea virginica), native to the Gulf of Mexico, are keystone species in estuarine ecosystems and are economically valued. Current research indicates that ocean acidification adversely affects the physiology and morphology of larval oysters, but the molecular mechanisms of this impact remain unstudied. Ocean acidification is contributed to by elevated atmospheric CO₂ due to increased anthropogenic activities, causing heightened partial pressure of CO₂ (pCO₂), and eutrophication from land-based runoff in the Gulf. The objective of this work was to determine the genomic response of the eastern oyster in Louisiana to simulated ocean acidification. …

Gene Expression Changes In The Mushroom Body Of Drosophila Melanogaster During A Time Course Of Long-Term Memory Formation And Maintenance, Spencer G. Jones

Electronic Thesis and Dissertation Repository

Long-term memory (LTM) requires gene transcription. However, there is still much to learn about which genes are transcriptionally regulated during LTM and the biological roles they play. Here, gene expression changes were characterized in Drosophila melanogaster over a time course of LTM formation and maintenance in neurons of the mushroom body (MB), a structure required for normal learning and memory. I identified 120 genes differentially expressed (q < 0.2, fold change > 1.3) 24h after LTM induction. Among these were 13 potential downstream targets for RNA localization by the known memory genes pumilo, staufen and oskar, several genes encoding chromatin regulators and seven genes with …

The Role Of Histone H2a.Z Abundance In Modulating Responses To Phosphorus Deficiency In Rice, Sara Zahraeifard

LSU Doctoral Dissertations

Histone variants contribute to chromatin complexity by creating specialized nucleosomes. Here, to investigate the pattern of H2A.Z histone variant distribution and its role in modulating gene expression in rice (Oryza sativa L.), we performed genome-wide profiling of ARP6-dependent H2A.Z deposition in rice seedlings. We demonstrated that under controlled conditions, the majority of H2A.Z deposition is within protein-coding genes (PCG), and the most highly expressed genes are enriched with H2A.Z at their 5’ ends near the transcription start site (TSS), whereas the medium- to low-expressed genes contain H2A.Z across the entire gene. Based on H2A.Z deposition, we categorized genes into …

Virulence Phenotypes Of Rotylenchulus Reniformis: Evaluation Of Host Status Of Cotton And Utility Of Single Nucleotide Polymorphisms (Snps) For Identification, Churamani Khanal

LSU Doctoral Dissertations

Comparative reproduction and pathogenicity of reniform nematode (Rotylenchulus reniformis) populations derived from single-egg masses and collected form West Carroll (WC), Rapides (RAP), Morehouse (MOR), and Tensas (TEN) parishes in Louisiana were evaluated in microplot and greenhouse trials. Data from microplot trials showed significant differences among isolates of reniform nematode in both reproduction and pathogenicity on upland cotton (Gossypium hirsutum) cultivars Phytogen 499 WRF, Deltapine 1133 B2RF, and Phytogen 333 WRF. Across all cotton cultivars, MOR and RAP isolates had the greatest and the least reproduction values of 331.8 and 230.2, respectively. Reduction in plant dry weight, …

All Roads Lead To Weediness: Stories About Weedy Rice Origins, Weedy Genes And Weed Competitiveness, Zhongyun Huang

Doctoral Dissertations

Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O.sativa), infests and persists in cultivated rice fields worldwide. Many weedy rice populations have evolved similar adaptive traits, considered part of the ‘agricultural weed syndrome’, making this an ideal model to study the genetic basis of parallel evolution. Using population genetics analyses of South Asian and US weedy rice, my research reveals multiple independent evolution events giving rise to weed groups in the two geographic areas. Weeds in South Asia have highly heterogenous genetic backgrounds, with contributions from both cultivated varieties (aus and indica) …

Using Competition Assays To Quantitatively Model Cooperative Binding By Transcription Factors And Other Ligands., Jacob Peacock, James B Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

BACKGROUND: The affinities of DNA binding proteins for target sites can be used to model the regulation of gene expression. These proteins can bind to DNA cooperatively, strongly impacting their affinity and specificity. However, current methods for measuring cooperativity do not provide the means to accurately predict binding behavior over a wide range of concentrations.

METHODS: We use standard computational and mathematical methods, and develop novel methods as described in Results.

RESULTS: We explore some complexities of cooperative binding, and develop an improved method for relating in vitro measurements to in vivo function, based on ternary complex formation. We derive …

Characterization Of Plant-Spider Mite Interactions And Establishment Of Tools For Spider Mite Functional Genetic Studies, Nicolas Bensoussan

Electronic Thesis and Dissertation Repository

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most polyphagous herbivores feeding on cell contents of over 1100 plant species including more than 150 crops. However, despite its important pest status and a growing understanding of the molecular basis of its interactions with plant hosts, knowledge of the way mites interface with the plant while feeding and the plant damage directly inflicted by mites is lacking. Likewise, while the use of the reverse genetic tools in plants facilitated our understanding of the establishment of defense mechanisms against spider mite herbivory, such tools are lacking for …

Characterization Of Acaricide Resistance, Plant-Mediated Rnai Against Two-Spotted Spider Mites (Tetranychus Urticae Koch), And Assessing Off- And Non-Target Effects, Hooman Hosseinzadeh Namin

Electronic Thesis and Dissertation Repository

The two-spotted spider mite (TSSM), Tetranychus urticae (Koch), is one of the most damaging agricultural pests in the world. It feeds on over 150 crops, causing considerable yield losses in greenhouses and agricultural fields. Currently, using synthetic acaricides is the main method to control TSSM. However, it can develop resistance to acaricides with repeated exposure, and typically resistance can occur within two to four years. To understand the underlying mechanisms of spider mite adaptation to acaricides is an essential part of resistance management strategy. The resistance ratio of the pyridaben-selected strain compared with the pre-selection strain was estimated at greater …

Characterization Of A Novel Mitochondrial Plasmid In Brassica, Mackenzie Strehle

UCARE Research Products

Possessing some of the largest and most complex genomes of any eukaryotic organelles, plant mitochondria are notorious for their rapidly rearranging genetic framework. In addition to containing a large and complex mitochondrial genome, the mitochondria of several plants in the genus Brassica have also been shown to contain an independent, self-replicating linear plasmid. Interestingly, the plasmid appears to be able to move independently between the cytoplasm and the mitochondria, and it can be paternally inherited, unlike the rest of the mitochondrial genome. The plasmid also has features similar to those of adenoviruses, including terminal inverted repeats and covalently bound proteins …

The Effect Of Diet On Midgut And Resulting Changes In Infectiousness Of Acmnpv Baculovirus In Trichoplusia Ni, Elizabeth Chen

Electronic Thesis and Dissertation Repository

The cabbage looper, Trichoplusia ni, a global generalist lepidopteran pest, has developed resistance to many synthetic and biological insecticides, requiring effective and environmentally acceptable alternatives. One possibility is the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). This baculovirus is highly infectious for T. ni, with potential as a biocontrol agent, however, its effectiveness is strongly influenced by dietary context. In this study, microscopy and transcriptomics were used to examine how the efficacy of this virus was affected when T. ni larvae were raised on different diets. Larvae raised on potato host plants had lower chitinase and chitin deacetylase transcript levels …

Development Of Markers For Embryonic Reproductive Competence In Assisted Reproduction, Xin Tao

Seton Hall University Dissertations and Theses (ETDs)

In humans, early embryo development is a complex process that consists of sequential events: oocyte maturation, fertilization, embryonic growth and implantation. Disruption of these highly regulated processes results in reproductive failure and infertility. This study characterizes and describes embryonic aneuploidy, mitochondrial content level and endometrial microbial environment related to reproductive competence, in particular instances in which failure results.

To examine the molecular underpinnings of mammalian gamete and early embryo chromosome segregation, we established a comprehensive chromosomal screening (CCS) method for mice poly bodies, oocytes and embryos by the application of whole genome amplification (WGA) and next generation sequencing (NGS). First, …

The Soybean Rfg1 Gene Restricts Nodulation By Sinorhizobium Fredii Usda193, Yinglun Fan, Jinge Liu, Shanhua Lyu, Qi Wang, Shengming Yang, Hongyan Zhu

Plant and Soil Sciences Faculty Publications

Sinorhizobium fredii is a fast-growing rhizobial species that can establish a nitrogen-fixing symbiosis with a wide range of legume species including soybeans (Glycine max). In soybeans, this interaction shows a high level of specificity such that particular S. fredii strains nodulate only a limited set of plant genotypes. Here we report the identification of a dominant gene in soybeans that restricts nodulation with S. fredii USDA193. Genetic mapping in an F2 population revealed co-segregation of the underlying locus with the previously cloned Rfg1 gene. The Rfg1 allele encodes a member of the Toll-interleukin receptor/nucleotide-binding site/leucine-rich repeat class of …

The Role Of T-Box Proteins In Vertebrate Germ Layer Formation And Patterning, Sushma Teegala

Dissertations, Theses, and Capstone Projects

All of the tissues in triploblastic organisms, with the exception of the germ cells, arise from the three germ layers, ectoderm, mesoderm and the endoderm. The identification of the genes that underlie the differentiation of these layers is crucial to our understanding of development. T-box family proteins are DNA-binding transcriptional regulators that play important roles during germ layer formation in the early vertebrate embryo. Well-characterized members of this family, including the transcriptional activators Brachyury and VegT, are essential for the proper formation of mesoderm and endoderm, respectively. To date, T-box proteins have not been shown to play a role in …

Examination Of Contribution Of Pentose Catabolism To Molecular Hydrogen Formation By Targeted Disruption Of Arabinose Isomerase (Araa) In The Hyperthermophilic Bacterium, Thermotoga Maritima, Derrick White

School of Biological Sciences: Dissertations, Theses, and Student Research

Thermotoga maritima ferments a broad range of sugars to form acetate, carbon dioxide, traces of lactate and near theoretic yields of molecular hydrogen (H₂). In this organism, the catabolism of pentose sugars such as arabinose depends on the interaction between the pentose phosphate, Embden Myerhoff and Entner Doudoroff pathways. While values for H₂ yield have been determined using pentose supplemented complex media (CM) and predicted by metabolic pathway reconstruction, quantitative in vivo measurements derived from pathway elimination have not been reported reflecting the lack of a genetic method for the creation of targeted mutations. Here, a spontaneous …

Itraq-Based Proteomics Analysis And Network Integration For Kernel Tissue Development In Maize, Long Zhang, Yongbin Dong, Qilei Wang, Chunguang Du, Wenwei Xiong, Xinyu Li, Sailan Zhu, Yuling Li

Department of Biology Faculty Scholarship and Creative Works

Grain weight is one of the most important yield components and a developmentally complex structure comprised of two major compartments (endosperm and pericarp) in maize (Zea mays L.), however, very little is known concerning the coordinated accumulation of the numerous proteins involved. Herein, we used isobaric tags for relative and absolute quantitation (iTRAQ)-based comparative proteomic method to analyze the characteristics of dynamic proteomics for endosperm and pericarp during grain development. Totally, 9539 proteins were identified for both components at four development stages, among which 1401 proteins were non-redundant, 232 proteins were specific in pericarp and 153 proteins were specific in …

Amelioration Of Prenatal Alcohol Effects By Environmental Enrichment In A Mouse Model Of Fasd, Aniruddho Chokroborty-Hoque

Electronic Thesis and Dissertation Repository

Maternal alcohol consumption during pregnancy results in a spectrum of behavioural and cognitive deficits collectively known as Fetal Alcohol Spectrum Disorders (FASD). Currently, little is know about if and how the external environment may modulate these deficits. I have used C57BL/6 mice to study this interaction between prenatal alcohol exposure and the postnatal environment. Alcohol exposure during synaptogenesis produces high levels of anxiety-like traits and decreased memory performance. Alcohol-exposed mice (and matched unexposed controls) were put in 'environmentally-enriched' conditions of voluntary exercise, physical activities and cognitive stimulation to ascertain the effects of a positive postnatal environment. The results show that …

Performing A Genetic Screen To Identify Factors That Promote Lncrna-Dependent Gene Repression, Chrishan Fernando, Cecilia Yiu, Sara Cloutier, Siwen Wang, Elizabeth Tran

The Summer Undergraduate Research Fellowship (SURF) Symposium

Long non-coding RNAs (lncRNAs) were once thought not to have useful functions in organisms but rather to be products of aberrant transcription. However, roles are being found for lncRNAs in beneficial processes such as controlling gene expression. In some of these cases, lncRNAs form R-loops in vivo. R-loops are nucleic acid structures consisting of hybridized strands of single-stranded DNA (ssDNA) and single-stranded RNA (ssRNA) as well as the displaced strand of ssDNA. Formation of these R-loops is important for gene regulation by the lncRNAs. However, factors that promote formation of lncRNA R-loops are not known. The gene PHO84 is being …

Tumor Formation In Response To Loss Of Chromatin Remodeler Chd5 In Zebrafish, Taylor R. Sabato, Erin L. Sorlien, Dr. Joseph P. Ogas

The Summer Undergraduate Research Fellowship (SURF) Symposium

Chromodomain helicase DNA binding protein 5 (CHD5) has been identified as a tumor suppressor in humans. Deletion or mutation of CHD5 has been observed in numerous cancers, including neuroblastoma and melanoma. We hypothesize that chd5 is also a tumor suppressor in zebrafish, a powerful model system to study tumorigenesis. Many genes involved in tumorigenesis are conserved in zebrafish, and they develop fully penetrant tumor phenotypes. We have created chd5 knock-out zebrafish using CRISPR/Cas9 and are monitoring them for tumor development. In addition to the chd5 knock-outs, we are undertaking a double-mutant approach by coupling loss …