Biochemistry Commons^™

Termination-Independent Role Of Rat1 In Cotranscriptional Splicing In Budding Yeast, Zuzer Hakimuddin Dhoondia

Wayne State University Dissertations

Rat1 is a 5′→3′ exoribonuclease in budding yeast belonging to the XRN-family of nucleases. It is a highly conserved protein with homologs being present in fission yeast, flies, worms, mice and humans. Rat1 and its homolog in metazoan have been shown to function in multiple facets of RNA metabolism. In this study, we report a novel role of Rat1 in splicing of pre-mRNA in budding yeast. In the absence of the functional Rat1 in the nucleus, an increase in the level of unspliced transcripts was observed in yeast cells. Strand-specific TRO analysis revealed that the accumulation of unspliced transcripts upon …

The Exploration Of Nanotoxicological Copper And Interspecific Saccharomyces Hybrids, Matthew Joseph Winans Phd

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nanotechnology takes advantage of cellular biology’s natural nanoscale operations by interacting with biomolecules differently than soluble or bulk materials, often altering normal cellular processes such as metabolism or growth. To gain a better understanding of how copper nanoparticles hybridized on cellulose fibers called carboxymethyl cellulose (CMC) affected growth of Saccharomyces cerevisiae, the mechanisms of toxicity were explored. Multiple methodologies covering genetics, proteomics, metallomics, and metabolomics were used during this investigation. The work that lead to this dissertation discovered that these cellulosic copper nanoparticles had a unique toxicity compared to copper. Further investigation suggested a possible ionic or molecular mimicry …

Seasonal Variation In Mitochondrial Bioenergetics Of The Bluegill Sunfish, Lepomis Macrochirus, From A Shallow Midwest River, Derick Isaac Lamptey

Masters Theses

As average global temperature increase, the frequency and magnitude of extreme temperatures in shallow aquatic ecosystems are more ubiquitous. In order to understand how these changing thermal regimes affect aquatic ectotherms, it is essential to develop studies evaluating the response of ectotherms to seasonal fluctuating thermal regimes. Previous studies on fluctuating temperature regimes have reported an increased physiological stress leading to morphological, behavioral and biochemical adaptations. From the latter, the adaptive capacity and seasonal performance associated with optimal function of the oxidative phosphorylation system (OXPHOS) are key for species persistence. However, studies on this matter are scarce. This study explores …

Proteomic Analysis Of Fetal Rat Neural Stem Cells After Treatment With Hericium Erinaceus, Bright Adam Test

University of the Pacific Theses and Dissertations

The fungus, Hericium erinaceus, has outstanding chemical properties, displaying health benefits in digestive, hepatic, and nervous tissues. Its ease of accessibility and use makes it one of the most common substances used for treatment in Eastern medicine. More and more recent research is confirming the incredible health benefits of this fungus, especially the impact that is seen on nervous tissue growth and recovery post-treatment. Such neurite outgrowth and myelin sheath regeneration could illustrate the beginning of the cure to lifelong neurodegenerative diseases such as Multiple Sclerosis. In this first-of-its-kind study, we cultured and differentiated fetal rat neural stem cells while …

Differential Analysis Of Individual Centruroides Vittatus Venom

Symposium of Student Scholars

Scorpions are well known, venomous arthropods (Class: Arachnida, Order: Scorpiones). Their venom is composed of neurotoxins, proteases and cytotoxic peptides which plays a major role in toxic components such as inflammatory, antimicrobial and hemolytic activity. Venom is key for the survival of scorpions as it is involved in defense against prey and in feeding on predators. Centruroides vittatus (bark scorpion) is commonly found in North America, with habitat ranges from Nebraska to southern Texas. For this study, scorpions were harvested from Laredo, Texas (27˚57’ N, 99˚43’ W), held in captivity for 4 months and fed a consistent diet of Acheta …

Multidrug Resistance Regulators Mara, Soxs, Rob, And Rama Repress Flagellar Gene Expression And Motility In Salmonella Enterica Serovar Typhimurium, Srinivas Thota, Lon Chubiz

Biology Department Faculty Works

Production of flagella is costly and subject to global multilayered regulation, which is reflected in the hierarchical control of flagellar production in many bacterial species. For Salmonella enterica serovar Typhimurium and its relatives, global regulation of flagellar production primarily occurs through the control of flhDC transcription and mRNA translation. In this study, the roles of the homologous multidrug resistance regulators MarA, SoxS, Rob, and RamA (constituting the mar-sox-rob regulon in S. Typhimurium) in regulating flagellar gene expression were explored. Each of these regulators was found to inhibit flagellar gene expression, production of flagella, and motility. To different degrees, repression via …

Dual Activities Of Plant Cgmp-Dependent Protein Kinase And Its Roles In Gibberellin Signaling And Salt Stress., Qingwen Shen, Xinqiao Zhan, Pei Yang, Jing Li, Jie Chen, Bing Tang, Xuemin Wang, Xuemin Wang, Yueyun Hong

Biology Department Faculty Works

Cyclic GMP (cGMP) is an important regulator in eukaryotes, and cGMP-dependent protein kinase (PKG) plays a key role in perceiving cellular cGMP in diverse physiological processes in animals. However, the molecular identity, property, and function of PKG in plants remain elusive. In this study, we have identified PKG from plants and characterized its role in mediating the gibberellin (GA) response in rice (Oryza sativa). PKGs from plants are structurally unique with an additional type 2C protein phosphatase domain. Rice PKG possesses both protein kinase and phosphatase activities, and cGMP stimulates its kinase activity but inhibits its phosphatase activity. One of …

Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr

Graduate Theses and Dissertations

Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …

Insect Population Dynamics, Varietal Preference And Performance Of Organic Bio-Pesticides, Anitha Chitturi, Jeanine Davis, Margaret Bloomquist, Franklin Quarcoo, Kokoasse Kpomblekou-A, Desmond Mortley

Professional Agricultural Workers Journal

Abstract

Organic farming prohibits use of synthetic agrochemicals and encourages use of Integrated Pest Management (IPM) methods. States in the Southeastern US generally lag behind the rest of the country in organic vegetable production partly because of high insect pressures that make it difficult to grow vegetables without pesticides. This study on summer squash (Cucurbita pepo), grown using organic management practices, was conducted at a research station located in Mills River, North Carolina. The objectives of the study were to assess insect population dynamics and to evaluate performance of three OMRI-approved bio-pesticides: Azadirachtin, Pyrethrin and Spinosad against major …

Understanding Excitation Energy Quenching In Isia, Hui-Yuan Steven Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

Cyanobacteria are photoautotrophic organisms that contribute a significant amount of global primary productivity. They are found in freshwater, marine and even some extremely severe environments. Among those environments, iron deficiency is one of the most common stress conditions in cyanobacterial habitats. To survive, cyanobacteria have evolved and developed several strategies to alleviate the damage caused by iron deficiency.

Iron stress-inducible protein (IsiA) is a chlorophyll-binding membrane protein found in cyanobacteria grown in iron-deficient conditions. During the past decades, considerable effort has been put on understanding how IsiA functions to help cyanobacteria survive iron deficiency. It has been reported that IsiA …

Podophyllum Peltatum: Relationship Of Colony Size And Age, Emily Holst, Heidi Keswick, David P. Warners

Student Papers and Reports

No abstract provided.

Stormwater Capture Via Green Infrastructure In The Plaster Creek Watershed, Kyle Dankert, Ana Singh, Deanna Geelhoed, David P. Warners

Student Papers and Reports

No abstract provided.

Green Team: Ecological Restoration Of Plaster Creek, Yeri Kim, Benjamin Steenwyk, Rachel Warners, David P. Warners, Gail Heffner

Student Papers and Reports

No abstract provided.

Does Thermotolerance In Daphnia Depend On The Mitochondrial Function?, Rajib Hasan

Electronic Theses and Dissertations

Thermotolerance limit in aquatic organism is set by the ability to sustain aerobic scope to sudden temperature shifts. This study tested the genetic and plastic differences in thermotolerance of Daphnia that can be explained by the differences in the ability to retain mitochondrial integrity at high temperatures. Five genotypes with different biogeographic origins were acclimated to 18^ᵒC and 25^ᵒC. We developed a rhodamine 123 in-vivo assay to measure mitochondrial membrane potential and observed higher fluorescent in heat damaged tissues as the disruption of the mitochondrial membrane potential. Significant effects on temperature tolerance were observed with CCCP …

Obscurin Mediates Ankyrin Complex Formation In The Heart, Janani Subramaniam

Dissertations and Theses (Open Access)

Distinctly organized domains of receptors, ion channels, transporters, signaling molecules, cell adhesion molecules, and contractile proteins are crucial to cardiac function. Interactions between adaptor proteins such as ankyrins and cytoskeletal proteins such as obscurin play a pivotal role in organizing these functional domains in cardiomyocytes. Therefore, dysfunction of both ankyrin as well as obscurin lead to a host of cardiovascular diseases such as arrhythmias and cardiomyopathies. Alternative splicing of ankyrin yields numerous isoforms that interact with obscurin at various sub-cellular domains. And while some of these obscurin-ankyrin complexes have been studied, many others have not been characterized. Further, previous studies …

Understanding How Map Kinases Influence Endothelial Nitric-Oxide Synthase Activity, Xzaviar Solone

Master of Science in Integrative Biology Theses

Mitogen activated protein kinases (MAPK) p38 and ERK have both been reported to bind endothelial nitric oxide synthase (eNOS) with submicromolar affinity via proposed interactions with a pentabasic non-canonical MAPK binding sequence in the autoinhibitory insertion of eNOS. The neuronal isoform, which lacks the pentabasic motif, did not bind either MAPK significantly. In the present study, the pentabasic motif was validated using predictive modeling programming, and eNOS phosphorylation by MAPKs (P38, ERK and JNK) was examined using in vitro kinase assays and immunoblotting. JNK phosphorylation at Ser¹¹⁴ contrasts with ERK, which phosphorylated Ser⁶⁰⁰, and p38, which phosphorylated …

Biotransformation Of Natural Antioxidants Osajin And Pomiferin By Cunninghamella Elegans (Atcc® 9245tm), Stephen Luis

Theses & Dissertations

Osajin and pomiferin, prenylated isoflavones extracted from the fruit of the osage orange tree (Maclura pomifera) have been reported as antioxidant compounds. The purpose of this study is to analyze the metabolization of osajin and pomiferin by the fungi Cunninghamella elegans (ATCC 9245) and supporting strains Umbelopsis ramanniana and Aspergillus fumigatus fresnius.

HPLC analysis of the extracts showed new, more polar compounds were formed, evidenced by peaks at lower retention times for each strain of fungi. To further investigate the metabolites produced, HPLC-guided chromatographic purification will be performed, and the pure metabolites will be analyzed through nuclear magnetic resonance and …

Relationships Of Protein Biomarkers Of The Urokinase Plasminogen Activator System With Expression Of Their Cognate Genes In Primary Breast Carcinomas., Seth B. Sereff

College of Arts & Sciences Senior Theses

Background: Urokinase plasminogen activator (uPA), its receptor uPAR and serine protease inhibitors PAI-1 or PAI-2 play key roles in tissue membrane remodeling and invasion of basement membranes by induction of a fibrinolytic pathway. Earlier studies reported that uPA and PAI-1 protein levels in breast carcinomas assist in prediction of response to chemotherapy. Our goal is to develop molecular signatures of candidate genes and identify novel relationships with these four protein biomarkers that demonstrate clinical utility for assessment of breast carcinoma outcomes.

Methods: This retrospective study used de-identified biomarker results and clinical outcomes from primary breast cancers that were stored in …

Preparation Of A Flavonol Specific Glucosyltransferase Found In Grapefruit And Site-Directed Mutants For Protein Crystallization, Aaron Birchfield

Electronic Theses and Dissertations

This research was designed to determine the conditions necessary to remove c-myc and 6x-His tags from a flavonol specific glucosyltransferase found in grapefruit (CP3GT) using thrombin in preparation for crystallization. X-ray crystallography of CP3GT crystals may elucidate structural features that account for flavonol specificity in some glucosyltransferase enzymes. A thrombin cleavage site was inserted into WT CP3GT and one mutant. Recombinant CP3GT was expressed in yeast and purified. Optimal conditions for thrombin digestion were explored. Digestion with 100U of thrombin for 2 hours at 4^o C was optimal for removing tags from CP3GT. Storage at 4^o C for …

Peroxisomal Protein Defects Disrupt Coordinated Peroxisomal Processes And Affect Early Seedling Development Through Accumulating Toxic Catabolic Intermediates, Ying Li

Dissertations

Many peroxisomal proteins act in β-oxidation processes on a range of substrates. It is unclear how these proteins are coordinated to determine the flux of peroxisomal processes and meet the requirements for plant growth and development. Using mutant analysis and metabolic profiling, I examined proteins predicted to act in fatty acid and indole-butyric-acid (IBA) β-oxidation. ECH2 confers enoyl-CoA hydratase activity for the auxiliary β-oxidation of fatty acids with an even cis-unsaturated bond. ECH2 was suggested to function in IBA β-oxidation, as ech2 seedlings have altered IBA response. ech2 seedlings have reduced root length and cotyledon area. ech2 seedlings accumulate 3-hydroxyoctenoate …

Mechanisms Of Oriented Cell Division And Their Roles In Tissue Development, Evan Blake Dewey

Biology ETDs

Properly executed cell division is crucial to development, maintenance, and longevity of multicellular organisms. Defects in both symmetric and asymmetric divisions can lead to improper developmental patterning, as well as genomic instability, disruption of tissue homeostasis, and cancer. Our research focuses on how regulators orchestrate proper cell divisions. Mushroom Body Defect (Mud) is one such regulator, and here we describe how Mud is regulated via the Hippo signaling pathway kinase Warts (Wts), showing Wts phosphorylates Mud to enhance interaction with the polarity protein Partner of Inscuteable, promoting spindle orientation activity. We next focus on another regulator, Shortstop (Shot), describing a …

Effects Of Electrical Stimulation On Glioma Cells In Vitro With Implications For Treating Chronic Pain: Development Of A Model System, David C. Platt

Theses and Dissertations

Glial cells comprise over 70% of the central nervous system cells and exhibit diverse functions including regulation of synaptic transmission, neuron protection/repair, maintenance of neuronal metabolism, and are implicated in the development of persistent neuropathic pain. In addition, a perturbation in the concentration of intracellular reactive oxygen species (ROS) and reactive nitrogen species (RNS) has likewise been associated with the development of a chronic pain state. This perturbation in ROS/RNS creates an environment of oxidative stress. However, the mechanism by which the pain signal transmission is modulated, and the roles ROS play in the perpetuation of the pain state are …

Characterization Of Psychromonas Aquimarina, A New Model Organism For Climate Change, Carrie Carpenter

Experiential Learning Projects

The current increase of average global temperature puts 25 to 35 percent of plant and animal species at an increased risk of extinction (Climate Change, 2018). Changing any environmental factor, such as increasing growth temperature, can significantly impact any organisms’ ability to survive. Because of the diversity of organisms on the planet, it is not feasible to study how each individually might adapt, but rather it is more efficient to study select organisms. This research focuses on a psychrophilic bacterium, Psychromonas aquimarina, which can survive in colder regions where most bacteria would not. This bacterium was chosen because climate change …

Unified Methods For Feature Selection In Large-Scale Genomic Studies With Censored Survival Outcomes, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

One of the major goals in large-scale genomic studies is to identify genes with a prognostic impact on time-to-event outcomes which provide insight into the disease's process. With rapid developments in high-throughput genomic technologies in the past two decades, the scientific community is able to monitor the expression levels of tens of thousands of genes and proteins resulting in enormous data sets where the number of genomic features is far greater than the number of subjects. Methods based on univariate Cox regression are often used to select genomic features related to survival outcome; however, the Cox model assumes proportional hazards …

Mechanisms To Regulate Genes Encoding Clinically Relevant Multidrug Transporters At The Crossroads Of Antibiotic Resistance And Oxidative Stress Detection, Afsana Sabrin

LSU Doctoral Dissertations

Multiple Antibiotic Resistance Regulators (MarRs) are DNA binding proteins involved in bacterial survival and pathogenesis. My PhD dissertation focuses on a MarR homolog, OstR, which regulates genes encoding major multidrug transporters, a resistance-nodulation-division (RND) and an E. coli multidrug resistance B (EmrB) efflux pump homolog in Burkholderia thailandensis. The ostR gene is divergently oriented from genes encoding a hypothetical protein (Hyp) and an RND transporter and adjacent to a gene encoding an EmrB transporter. OstR binds to the promoters of each gene (K_d = 64.9 ± 8.0 nM, K_d = 126.1 ± 10.9 nM and K …

Supervised Dimension Reduction For Large-Scale "Omics" Data With Censored Survival Outcomes Under Possible Non-Proportional Hazards, Lauren Spirko-Burns, Karthik Devarajan

COBRA Preprint Series

The past two decades have witnessed significant advances in high-throughput ``omics" technologies such as genomics, proteomics, metabolomics, transcriptomics and radiomics. These technologies have enabled simultaneous measurement of the expression levels of tens of thousands of features from individual patient samples and have generated enormous amounts of data that require analysis and interpretation. One specific area of interest has been in studying the relationship between these features and patient outcomes, such as overall and recurrence-free survival, with the goal of developing a predictive ``omics" profile. Large-scale studies often suffer from the presence of a large fraction of censored observations and potential …

Alternative Nad(P)H Dehydrogenase And Alternative Oxidase: Proposed Physiological Roles In Animals, Allison Mcdonald, Dmytro V. Gospodaryov

Biology Faculty Publications

The electron transport systems in mitochondria of many organisms contain alternative respiratory enzymes distinct from those of the canonical respiratory system depicted in textbooks. Two of these enzymes, the alternative NADH dehydrogenase and the alternative oxidase, were of interest to a limited circle of researchers until they were envisioned as gene therapy tools for mitochondrial disease treatment. Recently, these enzymes were discovered in several animals. Here, we analyse the functioning of alternative NADH dehydrogenases and oxidases in different organisms. We propose that both enzymes ensure bioenergetic and metabolic flexibility during environmental transitions or other conditions which may compromise the operation …

Escaping Death: Naloxone's Chemical Nature And Potential To Combat The Opioid Epidemic, Abigale Miller

Honors Program: Senior Projects (Public)

Naloxone is a life-saving drug with the ability to reverse an opioid overdose. As the opioid epidemic’s death toll rises, we can turn to Naloxone as a tool to combat the crisis. The epidemic, born of corruption, has a wide reach among the people of the United States, with especially firm grasps on middle-aged people, sufferers of chronic pain, white Americans and those living in the eastern portion of the country. Naloxone’s elegant design saves lives by effectively competing for a position on an opioid biding receptor in the brain to almost instantly end an overdose and restore normal breathing. …

Allosteric Mechanism Of The Circadian Protein Vivid Resolved Through Markov State Model And Machine Learning Analysis, Hongyu Zhou, Zheng Dong, Gennady M. Verkhivker, Brian D. Zoltowski, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

The fungal circadian clock photoreceptor Vivid (VVD) contains a photosensitive allosteric light, oxygen, voltage (LOV) domain that undergoes a large N-terminal conformational change. The mechanism by which a blue-light driven covalent bond formation leads to a global conformational change remains unclear, which hinders the further development of VVD as an optogenetic tool. We answered this question through a novel computational platform integrating Markov state models, machine learning methods, and newly developed community analysis algorithms. Applying this new integrative approach, we provided a quantitative evaluation of the contribution from the covalent bond to the protein global conformational change, and proposed an …

Student-Faculty Collaborative Research Grant Report, Megan Bestwick

Post-Grant Reports

Mitochondria are essential organelles in most eukaryotic cells because of their role in metabolism and the production of ATP by the oxidative phosphorylation (OXPHOS) pathway, as well as other key cellular processes. Metal cofactors, such as copper (Cu) and iron (Fe), are incorporated into OXPHOS protein complexes of yeast located within the inner membrane of the mitochondria. Misincorporation or modulation of these available metals in mitochondrial enzymes leads to the production of reactive oxygen species (ROS). ROS are reactive molecules containing oxygen such as peroxides, superoxide, and hydroxyl radicals. Yeast are a good model for studying aging and the effect …