Biochemistry, Biophysics, and Structural Biology Commons^™

Diversity Of The Major Histocompatibility Complex In African Penguins (Spheniscus Demersus) In Situ, Athena Schalk

Undergraduate Honors Thesis Projects

The Major Histocompatibility Complex (MHC) is responsible for the immune response in all jawed vertebrates and protects individuals against a variety of pathogens and diseases. Maintaining genetic diversity within the MHC exons is critical to protecting endangered species. African penguins (Spheniscus demersus) are in danger of losing their MHC diversity in isolated populations due to reductions in population size associated with environmental changes and human activity. This study analyzes the diversity within the exons in the DNA encoding the MHC by amplifying the exons through polymerase chain reaction and identifying alleles through denaturing gradient gel electrophoresis. Wild populations of …

Tip60 Regulation Of Δnp63Α Is Associated With Cisplatin Resistance, Akshay Hira, Andrew Stacy, Jin Zhang, Michael P. Craig, Madhavi Kadakia

Celebration of Undergraduate & Graduate Research, Scholarship, and Creative Activities Materials

About 5.4 million basal and squamous cell skin cancers are diagnosed every year in the US. ΔNp63a, a member of the p53 transcription factor family, is overexpressed in non-melanoma skin cancer and regulates cell survival, migration and invasion. TIP60 is histone acetyltransferase (HAT) which mediates cellular processes such as transcription and the DNA damage response (DDR). Previous studies in our lab have shown that overexpression of TIP60 induces ΔNp63a protein stabilization in a catalytic-dependent manner. Since ΔNp63a is known to transcriptionally regulate several DDR genes and promote cisplatin resistance, its stabilization by TIP60 may contribute to the failure of platinum-based …

Functions Of Cdk/Cyclin Complexes In Endoreplication Regulation By The Cdk Inhibitor Siamese, Kai Wang

LSU Doctoral Dissertations

Arabidopsis trichome (leaf hair) is a specialized single cell extended from epidermal cell on the leaves, which is a typical endoreplication and is also known as endoreduplication. Several D-type cyclins were tested to check the cell division in trichome, and the trichome expressing either CYCB1;2 or CDKB2;2 cannot trigger cell division, even if simultaneous expression of CYCB1;2 and CDKB2;2 failed to produce mitosis in trichome. Only CYCD3;1 specifically promotes multicellular trichome. cdkb1;1cdbk1;2 double mutants and sim cdkb1;1cdkb1;2 triple mutants exhibit the phenotype similar to the wild type and very limited cell division respectively. Overexpression of a CDKB1;1 dominant-negative construct that …

Molecular Differentiation Of Astragalus Species And Varieties From The Western United States: The Chloroplast Dna Bridge Between Evolution And Molecular Systematics, Marwa Neyaz, Daniel Cook, Rebecca Creamer

Poisonous Plant Research (PPR)

Locoweeds are the most widespread poisonous plant problem in the world and have been reported in the Western United States since the 1800s, causing tremendous losses in livestock. Consumption of locoweeds by grazing animals stimulates the neurological disease, locoism, characterized by weight loss, ataxia, and lack of muscular coordination. The name locoweed is used for Astragalus and Oxytropis species known to contain swainsonine, the toxic principle produced by the plant endophytic fungus Undifilum. Astragalus includes 2,500-3,000 species and many varieties that have almost identical morphological characteristics that overlap among species, leading to improper identification. Therefore, the aim of this study …

Identification Of Uncommon Antibiotic-Producing Illinois Soil Isolates, Lesly Muniz, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on student sourcing antibiotic discovery from the soil. We researched tester strains B. subtilis and E. coli from the soil isolates obtained. We further verified if the isolates were common antibiotic bacteria. Unfortunately, this project heavily relied on biochemical tests, colony morphology, and Gram stains to reject or fail to reject our hypothesis. Our goal was to discover new antibiotic-producing bacteria that could be beneficial in combating ESKAPE strains. A proper PCR and DNA extraction would be required …

Pseudomonas And Bacillus Soil Isolates Produce Antibiotics, Chelsea Brandt, Dr. Lori Scott

Identifying and Characterizing Novel Antibiotic Producing Microbes From the Soil

The recent emergence of antibiotic resistance bacterial strains presents a significant challenge and threat to human healthcare. While new methods of treatment such as bacteriophage therapy and combinations of existing antibiotics are being researched, the human population is in dire need of new antibiotics to replace those that are ineffective. This research addresses this need by identifying antibiotic producing bacteria in a soil sample from Davenport, IA. This project is a collaboration with the Tiny Earth Project Initiative (TEPI), which is a global network of educators and students focused on studentsourcing antibiotic discovery from soil. Microbiology lab techniques and 16S …

Characterization Of The Dyrk1a Protein-Protein Interaction Network, Varsha Ananthapadmanabhan

Theses and Dissertations

Human Dual specificity tyrosine (Y)-Regulated Kinase 1A (DYRK1A) is a protein kinase encoded by a dosage-dependent gene. An extra copy of DYRK1A contributes to Down syndrome (DS) pathogenesis while loss of one allele causes severe mental retardation and autism. DYRK1A is involved in phosphorylation of several proteins that regulate cell cycle control and tumor suppression. However, the function and regulation of this kinase is not well understood and current knowledge does not fully explain dosage-dependent function of this important kinase. Our previous proteomic studies identified several novel DYRK1A interacting proteins including RNF169, FAM117B, TROAP, LZTS1, LZTS2 and DCAF7. In this …

Epigenetic Implications In Inorganic Arsenic-Mediated Carcinogenesis, Meredith Eckstein

Theses and Dissertations--Molecular and Cellular Biochemistry

Chronic, low dose exposure to inorganic arsenic (iAs) is a public health concern throughout the world, contributing to the development of many diseases, including lung cancer. Several mechanisms for iAs-mediated carcinogenesis have been proposed, of which the production of reactive oxygen species and formation of chromosomal aberrations are the most studied. Another equally important, yet less studied mechanism is dysregulation of epigenetic marks. “Epigenetics” refers to changes that occur on the DNA and chromatin that do not alter base pair identity, but alter compaction, expression, and regulation of specific DNA sequences. There are several types of epigenetic marks including histone …

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 …

Characterization Of The Tsc/Dyrk1a Interaction, Supriya Joshi

Theses and Dissertations

The Tuberous sclerosis complex (TSC) includes TSC1, TSC2 and the TBC1D7 subunits that together function as a principal inhibitor of the mTOR protein kinase complex 1 (mTORC1). mTORC1 is a master regulator of cell growth and proliferation that responds to signaling cues such as growth factors and nutrient availability. Proteomic studies in our lab revealed an interaction between the TSC subunits and DYRK1A, a ubiquitous protein kinase encoded by a gene located in the Down syndrome (DS) region on human chr21. In this study, we sought to validate the interaction of the TSC components with DYRK1A and to determine the …

A Kinesin Adapter Directly Mediates Dendritic Mrna Localization During Neural Development In Mice, Hao Wu, Jing Zhou, Tianhui Zhu, Ivan Cohen, Jason Dictenberg

Publications and Research

Motor protein-based active transport is essential for mRNA localization and local translation in animal cells, yet how mRNA granules interact with motor proteins remains poorly understood. Using an unbiased yeast two–hybrid screen for interactions between murine RNA-binding proteins (RBPs) and motor proteins, here we identified protein interaction with APP tail-1 (PAT1) as a potential direct adapter between zipcode-binding protein 1 (ZBP1, a β-actin RBP) and the kinesin-I motor complex. The amino acid sequence of mouse PAT1 is similar to that of the kinesin light chain (KLC), and we found that PAT1 binds to KLC directly. Studying PAT1 in mouse …

Investigating The Role Of Centromeric Repeats In Female Meiotic Drive, Jocelyn Crawford

CMC Senior Theses

Female meiotic drive is an unequal transmission of alleles that arises through the competition of paired chromosomes for inclusion in the egg, resulting in an increase in frequency of the driven alleles regardless of their effect on fitness of the individual. In Mimulus guttatus (monkeyflower) second filial generations, driven alleles display transmission advantages resulting in the virtual elimination of recessive homozygotes, while the equivalent lines lacking drive elements conform to traditional Mendelian segregation population ratios. Centromeres have been identified as mechanistic drive elements due to their role in chromosomal segregation during female meiosis, with Mimulus providing the best documented case …

Simultaneous Delivery Of Crispr/Cas Complexes And Donor Dna Using Cell-Penetrating Peptide-Adaptors, Maria Mugure Mbugua

Master of Science in Chemical Sciences Theses

Clustered Regularly Interspaced Palindromic Repeats (CRISPR)/CRISPR associated protein (Cas) complexes are becoming the preferred technique for genomic editing because of their precision, efficiency and accuracy. Prokaryotes naturally use CRISPR/Cas complexes to detect and eliminate foreign nucleic acids after infections. Cas proteins form complexes with RNA to cause double-stranded breaks (DSBs) in the invader’s sequence. Researchers are trying to use CRISPR complexes to treat many human diseases caused by these mutations. Research using CRISPR/Cas systems in the treatments of many of the genetic diseases has resulted in misfortunes (such as toxicity to the patient or new diseases) because of the method …

Mechanisms And Consequences Of Myb Gene Activation In Salivary Gland Tumors, Candace Frerich

Biomedical Sciences ETDs

Salivary gland adenoid cystic carcinoma (ACC) is an aggressive tumor with a tendency to infiltrate surrounding nerves and metastasize to distant sites. The standard treatment often fails to control local tumor recurrence and distant metastases and no approved targeted therapeutic options exist for these tumors. The goal of our studies was to reveal the molecular mechanisms driving ACC tumor development and novel drug targets to improve patient morbidity and mortality.

We first analyzed clinical and RNA-sequencing (RNA-seq) data for 68 formalin-fixed paraffin-embedded (FFPE) ACC tumor samples and described previously unappreciated molecular heterogeneity that predicts patient outcome. The poor outcome subgroup …

Nitric Oxide Is Involved In Heavy Ion-Induced Non-Targeted Effects In Human Fibroblasts, Megumi Hada, Premkumar B. Saganti, Francis A. Cucinotta

Health Physics and Diagnostic Sciences Faculty Research

Previously, we investigated the dose response for chromosomal aberration (CA) for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) particles, and showed that the dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Our results suggested that the simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. Nitric oxide (NO) has been reported as a candidate for intercellular signaling for NTE in many studies. In order to estimate the …

Towards A Mathematical Model Of Motility Using Dictyostelium Discoideum: Proteins And Geometric Features That Regulate Bleb-Based Motility, Zully Santiago

Dissertations, Theses, and Capstone Projects

A variety of biological functions depend on actin organization. The organization of actin is tightly regulated by a plethora of extracellular and intracellular signaling, scaffolding, and actin-binding proteins. Dysfunctions in this regulation lead to immune diseases, increased susceptibility to pathogens, neurodegenerative diseases, developmental disorders, and cancer metastasis. A variety of actin-dependent processes, including cell motility, are regulated by several proteins of interest: Paxillin, a scaffolding protein; WASP, an actin nucleating protein; SCAR/WAVE, another WASP family actin nucleating protein; Talin, a cortex-to-membrane binding protein; Myosin II, an F-actin contracting motor protein; and Protein Kinase C, a protein kinase. D. discoideum cells …

Characterization Of Human Dutpase, Shawna Marie Rotoli

Graduate School of Biomedical Sciences Theses and Dissertations

Deoxyuridine nucleotidyl transferase (dUTPase) is an enzyme found in all organisms that have thymine as a component of DNA. It catalyzes the hydrolysis of dUTP to dUMP and pyrophosphate thus precluding the buildup of dUTP pools as well as providing the substrate, dUMP, for the de novo synthesis of thymidylate. In Homo sapiens, there are four isoforms: mitochondrial (mDut), nuclear (nDut), variant 3 and variant 4. This work is largely focused on nDut. Using structural and MS analyses of recombinant dUTPase constructs, an intermolecular disulfide bridge between cysteine-3 of each nDut monomer was discovered. It was found that these two …

The Effect Of Intracellular Zinc Levels In Escherichia Coli On Metallo-Β-Lactamase Activity, Jill Thompson

Graduate School of Biomedical Sciences Theses and Dissertations

Antibiotic resistance is a consequence of evolution via natural selection and poses a serious threat to the world's population. Escherichia coli, and other bacterial species, have acquired genes encoding Metallo-β-Lactamases (MBLs). MBLs are zinc-dependent enzymes that degrade most β-lactam antibiotics, and have emerged as important antibacterial resistance determinants in multidrug resistant pathogens. There are several different families of MBLs, and the major clinically relevant ones are Verona Integrated-encoded Metallo-β-Lactamases (VIMs), Imipenemases (IMPs), and New Delhi Metallo-β-Lactamases (NDMs). These enzymes confer high level resistance to penicillins, cephalosporins, and carbapenems, and are not inhibited by FDA-approved β-lactamase inhibitors. Variants of NDM have …

A Dedicated Chaperone Mediates The Safe Transfer Of Mitoribosomal Proteins To Their Site Of Assembly, Gabrielle Ashley Hillman

Graduate School of Biomedical Sciences Theses and Dissertations

Mitochondrial ribosomes are functionally specialized for the synthesis of several essential inner membrane proteins of the respiratory chain. While remarkable progress has recently been made towards understanding the structure of mitoribosomes, the unique pathways and factors that facilitate their biogenesis remain largely unknown. This dissertation defines the physiological role of an evolutionarily conserved yeast protein called Mam33 in mitochondrial ribosome assembly. The biomedical relevance of this finding stems from the fact that mutations or changes in its expression of the human ortholog p32 result in mitochondrial dysfunction. In human patients, bi-allelic mutations cause severe multisystemic defects in mitochondrial energy metabolism, …

The Role And Regulation Of Alternative Polyadenylation In The Dna Damage Response, Michael R. Murphy

Dissertations, Theses, and Capstone Projects

Cellular homeostasis is achieved by the dynamic flux in gene expression. Post-transcriptional regulation of coding and non-coding RNA offers a fast method of adapting to a changing cellular environment, including deadenylation, microRNA (miRNA) pathway, and alternative polyadenylation (APA). In this dissertation, I explored some of the mechanisms involved in the post-transcriptional regulation of gene expression. The main hypothesis in these studies is that a single APA event after DNA damage is governed by specific conditions and factors outside of current known regulators of APA, and that the resultant transcript has a role in the DNA damage response (DDR). My aims …

Thiol-Based Misfolding: Linking Redox Balance To Cytosolic Proteostasis, Ford Amy

Dissertations and Theses (Open Access)

The eukaryotic cytosolic proteome is vulnerable to changes in proteostatic and redox balance caused by temperature, pH, oxidants and xenobiotics. Cysteine-containing proteins are especially at risk as the thiol side chain is subject to oxidation, adduction and chelation by thiol-reactive compounds. All of these thiol-modifiers have been demonstrated to induce the heat shock response and recruit protein chaperones to sites of presumed protein aggregation in the budding yeast Saccharomyces cerevisiae. However, endogenous targets of thiol stress toxicity responsible for these outcomes are largely unknown. Furthermore, I hypothesize proteins identified as redox-active are prone to misfolding and aggregation by thiol-specific …

Cellular Localization Of Rad51d Mutant Proteins And The Application Of Art To Increase Scientific Literacy In America, Claire L. Chabot

Senior Theses

Ovarian cancers are the leading cause of death from cancer of the female reproductive system. Approximately 50% of ovarian cancers have defects in the homologous recombination (HR) DNA repair pathway that is required for the repair of DNA double-stranded breaks. The status of HR genes, such as BRCA1, BRCA2, and the RAD51 family, contributes to ovarian cancer development as well as treatment decisions regarding chemotherapy, radiation, and immunotherapy. The overarching goal of this project is to identify new insights into HR that can integrate with Precision Medicine Initiatives and align with the goals of the Cancer Moonshot 2020 Program. I …

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 …

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 …

Mechanisms Of Trinucleotide Repeat Instability During Dna Synthesis, Kara Y. Chan

Theses and Dissertations--Toxicology and Cancer Biology

Genomic instability, in the form of gene mutations, insertions/deletions, and gene amplifications, is one of the hallmarks in many types of cancers and other inheritable genetic disorders. Trinucleotide repeat (TNR) disorders, such as Huntington’s disease (HD) and Myotonic dystrophy (DM) can be inherited and repeats may be extended through subsequent generations. However, it is not clear how the CAG repeats expand through generations in HD. Two possible repeat expansion mechanisms include: 1) polymerase mediated repeat extension; 2) persistent TNR hairpin structure formation persisting in the genome resulting in expansion after subsequent cell division. Recent in vitro studies suggested that a …

The Impact Of Household Biocides And Antibiotics On Aquatic Microbial Community Composition, Abdulaziz Saud M Alrashdi

Dissertations, Master's Theses and Master's Reports

Triclosan (TCS) is antimicrobial agent that is used in a lot of consumer products, including toothpaste, liquid and bar soap, and cosmetics. TCS has been found in many lakes and rivers in the United States. However, The Food and Drug Administration (FDA) banned TCS recently and it will no longer be used in household products. Despite the recent ban, TCS is known to persist in the environment and may have long-term impacts. We conducted an experiment on using fresh water from three locations Houghton, Green Bay and the Huron Mountains. Our goals in the study is to assess the impact …

Mutations Of Fus Cause Aggregation Of Rna Binding Proteins, Disruptions In Protein Synthesis, And Dysregulation Of Nonsense Mediated Decay, Marisa Elizabeth Kamelgarn

Theses and Dissertations--Toxicology and Cancer Biology

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by motor neuron death and subsequent muscle atrophy. Approximately 15% of ALS cases are inheritable, and mutations in the Fused in Sarcoma (FUS) gene contribute to approximately 5% of these cases, as well as about 2% of sporadic cases. FUS performs a diverse set of cellular functions, including being a major regulator of RNA metabolism. FUS undergoes liquid- liquid phase transition in vitro, allowing for its participation in stress granules and RNA transport granules. Phase transition also contributes to the formation of cytoplasmic inclusions found in the …

Impact Of Seasonal And Host-Related Factors On The Intestinal Microbiome And Cestode Community Of Sorex Cinereus And Sorex Monticola, Katelyn D. Cranmer

College of Graduate Studies: Theses & Dissertations

The intestinal microbiome of mammals plays a significant role in host health and response to environmental stimuli and can include both beneficial native bacteria as well as parasitic worms. In this study, I examined the intestinal cestode and bacterial communities of two closely related species of shrew, Sorex monticola and Sorex cinereus, over a six month period in 2016. Specimens were collected approximately every three weeks from May to October from the Sangre de Cristo Mountains in Cowles, New Mexico. A total of 79 shrews were prepared with the gastrointestinal tracts removed and flash-frozen in liquid nitrogen. An additional …

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey

Masters Theses

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or …

Characterizing Chromosomal Aberrations In Cells Deficient For Both Atm And Msh2, Yeliz Inalman

Dissertations and Theses

Ataxia telangiectasia mutated (ATM) and mutS homologue 2 (MSH2) are important DNA repair proteins that participate in DNA repair pathways to maintain genomic integrity. Mice deficient for ATM and MSH2 mice are viable. However, ATM^-/- mice show growth retardation, neurological defects, and spontaneous lymphomagenesis. MSH2^-/- mice suffer from aggressive lymphoid tumors between two to five months of age and have increased microsatellite instability, which predisposes MSH2^-/- mice to carcinomas. However, mice deficient in both ATM and MSH2 are unable to survive beyond postnatal day 21 (P21). The observed lethality in ATM^-/-MSH2^-/- mice may result …