Molecular Biology Commons^™

Assessing The Effects Of Streptozotocin-Induced Hyperglycemia On Amyloid Beta Accumulation And Cognitive Behavior In A Mouse Model Of Alzheimer’S Disease-Related Pathology, Andrew Adonay Ortiz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer’s disease (AD) is an irreversible and devastating neurodegenerative disease characterized by progressive synaptic, dendritic, glial, and neuronal loss, collectively leading to impairments in learning, memory, and deterioration of cognitive and behavioral functions. AD is the most common form of dementia accounting for 60-80% of all cases. AD affects approximately 7 million Americans and is the 6th leading cause of death in the US. Furthermore, by 2050, the US is projected to spend over $1.1 trillion on AD-related treatments. Pathological hallmarks of AD include beta-amyloid (Aβ) plaques, intracellular neurofibrillary tangles (NFTs), and chronic neuroinflammation, which can promote and exacerbate both …

Detection And Quantification Of Total Airborne Fungi And Coccidioides Species In Environmental Samples, Theresa T. Roehr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Fungal exposure can cause acute and chronic illnesses or exacerbate existing illnesses. Some fungi are opportunistic pathogens and can lead to serious systemic fungal infections. In 2020, more than 150 million cases of severe fungal infections were reported globally resulting in an estimated 1.7 million deaths. Coccidioidomycosis, or Valley fever, is classified as a serious fungal infection caused by the fungi Coccidioides immitis and C. posadasii. These particular fungi are prevalent in the soil of the Southwestern United States, including Las Vegas, Nevada. In 2024, there were a total of 269 cases of Valley fever reported in Nevada, and …

Integrated Transcriptomics And Proteomics Study Of Starvation Selected Drosophila Melanogaster, Aavash Adhikari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drosophila melanogaster, selected for starvation resistance exhibits phenotypic traits such as increased body size, slower development, reduced fecundity and obesity like characteristics including higher lipid reserves and cardiac dysfunction. While prior studies have explored the metabolic and biochemical changes in these flies, the underlying genetic and molecular mechanisms remain unclear. This study aims to investigate the gene expression and protein abundance in starvation-selected Drosophila through RNAseq, proteomics, and integrating both datasets using the MixOmics package in R. I found differential gene expression in the fat body at the third instar larval stage, particularly in pathways related to lipid metabolism, calcium …

Evaluating Human Plasma Biomakers For Alzheimer's Disease; Phosphorylated-Tau 217, Phosphorylated-Tau 181, And Glial Fibrillary Acidic Protein, Mason Jonah, Mayarae N. Mugosa, Bella Hou, Emma-Nikole Krilchev, Zhengshi Yang, Dietmar Cordes, Aaron Ritter, Jefferson W. Kinney

Undergraduate Research Symposium Posters

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease that is primarily identifiable by amyloid-beta (Aβ) neuronal plaques, neurofibrillary tangles (NFT) that form as aggregates of hyperphosphorylated tau (ptau) proteins clump together, and the presence of neuroinflammation; all of which are otherwise known as the hallmarks of AD pathology. Recent emerging research has discovered striking similarities between AD and diabetes mellitus pathology, illustrating how insulin deficiency and insulin resistance–both of which result in the chronic hyperglycemic state seen in the diabetic–are involved in an increase in the phosphorylation of tau. This leads to and intensifies the formation of intracellular NFTs serving …

Genome-Guided Isolation Of The Hyperthermophilic Aerobe Fervidibacter Sacchari Reveals Conserved Polysaccharide Metabolism In The Armatimonadota, Nancy O. Nou, Jonathan K. Covington, Dengxun Lai, Xavier Mayali, Cale O. Seymour, Juliet Johnston, Jian-Yu Jiao, Steffen Buessecker, Damon Mosier, Alise R. Muok, Nicole Torosian, Allison M. Cook, Ariane Briegel, Tanja Woyke, Emiley Eloe-Fadrosh, Nicole Shapiro, Scott G. Bryan, Savannah Sleezer, Joshua Dimapilis, Cristina Gonzalez, Lizett Gonzalez, Marlene Noriega, Matthias Hess, Ross P. Carlson, Lan Liu, Meng-Meng Li, Zheng-Han Lian, Siqii Zhu, Fan Liu, Xian Sun, Beile Gao, Ritesh Mewalal, Miranda Harmon-Smith, Ian K. Blaby, Jan-Fang Cheng, Peter K. Weber, Gabriela Grigorean, Wen-Jun Li, Anne E. Dekas, Jennifer E. Pett-Ridge, Jeremy A. Dodsworth, Marike Palmer, Brian P. Hedlund

Life Sciences Faculty Research

Few aerobic hyperthermophilic microorganisms degrade polysaccharides. Here, we describe the genome-enabled enrichment and optical tweezer-based isolation of an aerobic polysaccharide-degrading hyperthermophile, Fervidibacter sacchari, previously ascribed to candidate phylum Fervidibacteria. F. sacchari uses polysaccharides and monosaccharides for growth at 65–87.5 °C and expresses 191 carbohydrate-active enzymes (CAZymes) according to RNA-Seq and proteomics, including 31 with unusual glycoside hydrolase domains (GH109, GH177, GH179). Fluorescence in-situ hybridization and nanoscale secondary ion mass spectrometry confirmed rapid assimilation of 13C-starch in spring sediments. Purified GHs were optimally active at 80–100 °C on ten different polysaccharides. Finally, we propose reassigning Fervidibacteria as a class …

Cellular Mechanisms Of Embryonic Eye Regrowth In Xenopus Laevis, Randolph L. Grell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The African Clawed Frog, Xenopus laevis, has been an indispensable model organism for over 100 years in the study of embryogenesis and development. In recent years, this vertebrate model has emerged as a robust tool for deciphering the cellular and molecular mechanisms underlying various modes of tissue, limb, and organ regeneration. In the context of eye repair, Xenopus offers a unique model, where the adult frog eye has limited regenerative capacity compared to its pre-metamorphic embryonic and tadpole forms, which exhibit a robust capacity for regrowth. Understanding the intricate molecular mechanisms that underlie this developmental shift in regrowth ability …

Long-Range Regulation By The Shigella Virulence Gene Regulator, Virb, Cody Cris

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nucleoid-structuring proteins (NSPs) in bacterial cells can exert gene regulatory effects over great distances on DNA. This contrasts with the traditional view of bacterial transcriptional regulation, where transcription factors bind cis-acting regulatory sites proximal (<250 bp) to promoters to influence gene expression. In Shigella species, the histone-like nucleoid-structuring protein (H-NS) transcriptionally silences many genes on the large (~220 kb) virulence plasmid. During host colonization, however, silencing by H-NS is alleviated by the anti-silencer protein, VirB, which remodels the H-NS:DNA complex. This transcriptional anti-silencing is mediated by VirB:DNA interactions and the modulation of DNA supercoiling, which lead to the up-regulation of virulence genes. VirB is a central regulator of Shigella virulence, but the mechanistic basis for transcriptional regulation is incompletely characterized. Here, I focus on the potential for VirB to regulate transcription from remotely located DNA binding sites. Employing complementary in vivo approaches, I assessed the spatial stringency of the VirB binding site and elucidated how varying cellular VirB levels impacts regulation over different distances. I also evaluated how a molecular roadblock on DNA influences remote regulation by VirB. Additionally, I developed control tools to validate the ability of VirB to spread along DNA, an activity of VirB that putatively drives transcriptional regulation. These data are consistent with transcriptional anti-silencing being driven by VirB spreading along DNA. Overall, these findings highlight how VirB is not a conventional transcriptional regulator and broaden our perspective on transcriptional control in bacteria. Furthermore, this work contributes to our understanding of long-range gene regulatory effects, which are frequently overlooked and poorly characterized in bacteria.

Effects Of Cations And Dipicolinic Acid On B. Anthracis Spore Physiology And Cytotoxicity, Chandler P. Hassan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Inhalation of Bacillus anthracis spores leads to the most severe form of anthrax. Following phagocytosis by alveolar macrophages, spores germinate inside the phagolysosome. The mechanism used by the newly germinated B. anthracis cells to survive within macrophages is not completely understood.B. anthracis spores contain large concentrations of calcium in complex with dipicolinic acid (Ca-DPA). Upon germination, the cell excretes the large depot of Ca-DPA. DPA is an amphipathic molecule that could act as a buffer and modulate phagolysosome acidification. Intracellular calcium overload can disrupt signaling pathways required for normal macrophage function and trigger cell death. We hypothesized the release of …

Data Supporting A Saturation Mutagenesis Assay For Tat-Driven Transcription With The Gigaassay, Ronald Benjamin, Christopher J. Giacoletto, Zachary T. Fitzhugh, Danielle Eames, Lindsay Buczek, Xiaogang Wu, Jacklyn Newsome, Mira V. Han, Tony Pearson, Zhi Wei, Atoshi Banerjee, Lancer Brown, Liz J. Valente, Shirley Shen, Hong-Wen Deng, Martin R. Schiller

Life Sciences Faculty Research

The data in this article are associated with the research paper “GigaAssay – an adaptable high-throughput saturation mutagenesis assay". The raw data are sequence reads of HIV-1 Tat cDNA amplified from cellular genomic DNA in a new single-pot saturation mutagenesis assay designated the “GigaAssay”. A bioinformatic pipeline and parameters used to analyze the data. Raw, processed, analyzed, and filtered data are reported. The data is processed to calculate the Tat-driven transcription activity for cells with each possible single amino acid substitution in Tat. This data can be reused to interpret Tat intermolecular interactions and HIV latency. This is one of …

Seqcode: A Nomenclatural Code For Prokaryotes Described From Sequence Data, Brian P. Hedlund, Maria Chuvochina, Philip Hugenholtz, Konstantinos T. Konstantinidis, Alison E. Murray, Marike Palmer, Donovan H. Parks, Alexander J. Probst, Anna-Louise Reysenbach, Luis M. Rodriguez-R, Ramon Rossello-Mora, Iain C. Sutcliffe, Stephanus N. Venter, William B. Whitman

Life Sciences Faculty Research

Most prokaryotes are not available as pure cultures and therefore ineligible for naming under the rules and recommendations of the International Code of Nomenclature of Prokaryotes (ICNP). Here we summarize the development of the SeqCode, a code of nomenclature under which genome sequences serve as nomenclatural types. This code enables valid publication of names of prokaryotes based upon isolate genome, metagenome-assembled genome or single-amplified genome sequences. Otherwise, it is similar to the ICNP with regard to the formation of names and rules of priority. It operates through the SeqCode Registry (https://seqco.de/), a registration portal through which names and …

Differential Expression Of Cellular And Exosomal Microrna Isolated From Oral Cancer Cells And Their Resistance To Chemotherapy, Brady Petersen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: MicroRNAs are abundant small non-coding RNA with a variety of known functions, including transcriptional activation and inhibition. Recent evidence has suggested that microRNA expression may influence the responsiveness of some cancers to chemotherapy, including liver and lung cancers. Some evidence has now suggested that specific microRNAs, such as miR-21, miR-155, and miR-375, may influence oral cancer responsiveness to chemotherapy – although much remains to be discovered.

Objective: Based upon the lack of evidence in this area, the primary objective of this study was to evaluate microRNA expression and responsiveness among oral cancers.

Methods: Five commercially available oral cancer cell …

Development Of The Seqcode: A Proposed Nomenclatural Code For Uncultivated Prokaryotes With Dna Sequences As Type, William B. Whitman, Maria Chuvochina, Brian P. Hedlund, Philip Hugenholtz, Konstantinos T. Konstantinidis, Alison E. Murray, Marike Palmer, Donovan H. Parks, Alexander J. Probst, Anna-Louise Reysenbach, Luis M. Rodriguez-R, Ramon Rossello-Mora, Iain Sutcliffe, Stephanus N. Venter

Life Sciences Faculty Research

Over the last fifteen years, genomics has become fully integrated into prokaryotic systematics. The genomes of most type strains have been sequenced, genome sequence similarity is widely used for delineation of species, and phylogenomic methods are commonly used for classification of higher taxonomic ranks. Additionally, environmental genomics has revealed a vast diversity of as-yetuncultivated taxa. In response to these developments, a new code of nomenclature, the Code of Nomenclature of Prokaryotes Described from Sequence Data (SeqCode), has been developed over the last two years to allow naming of Archaea and Bacteria using DNA sequences as the nomenclatural types. The SeqCode …

Xrcc4 And Mre11 Roles And Transcriptional Response To Repair Of Talen-Induced Double-Strand Dna Breaks, Ronald Benjamin, Atoshi Banerjee, Xiaogang Wu, Corey Geurink, Lindsay Buczek, Danielle Eames, Sara G. Trimidal, Janice M. Pluth, Martin R. Schiller

Health Physics and Diagnostic Sciences Faculty Research

Double-strand breaks (DSB) are one of the most lethal forms of DNA damage that, if left unrepaired, can lead to genomic instability, cellular transformation, and cell death. In this work, we examined how repair of transcription activator-like effector nuclease (TALEN)-induced DNA damage was altered when knocking out, or inhibiting a function of, two DNA repair proteins, XRCC4 and MRE11, respectively. We developed a fluorescent reporter assay that uses TALENs to introduce DSB and detected repair by the presence of GFP fluorescence. We observed repair of TALEN-induced breaks in the XRCC4 knockout cells treated with mirin (a pharmacological inhibitor of MRE11 …

Dual Activities Of Acc Synthase: Novel Clues Regarding The Molecular Evolution Of Acs Genes, Chang Xu, Bowei Hao, Gongling Sun, Yuanyuan Mei, Lifang Sun, Yunmei Sun, Yibo Wang, Yongyan Zhang, Wei Zhang, Mengyuan Zhang, Yue Zhang, Dan Wang, Zihe Rao, Xin Li, Jeffery Shen, Ning Ning Wang

Life Sciences Faculty Research

Ethylene plays profound roles in plant development. The rate-limiting enzyme of ethylene biosynthesis is 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS), which is generally believed to be a single-activity enzyme evolving from aspartate aminotransferases. Here, we demonstrate that, in addition to catalyzing the conversion of S-adenosyl-methionine to the ethylene precursor ACC, genuine ACSs widely have Cβ-S lyase activity. Two N-terminal motifs, including a glutamine residue, are essential for conferring ACS activity to ACS-like proteins. Motif and activity analyses of ACS-like proteins from plants at different evolutionary stages suggest that the ACC-dependent pathway is uniquely developed in seed plants. A putative catalytic mechanism for …

Bone Morphogenetic Protein Signaling Requirement In Centripetal Migration In Drosophila Melanogaster Oogenesis, Sheila Mosallaei

UNLV Theses, Dissertations, Professional Papers, and Capstones

Cells interact with each other via signals to coordinate migration for proper tissue development and maintenance, immunity and tissue repair. Signals regulate migration via changes to cytoskeletal components or transcriptional regulation. Here, I used Drosophila melanogaster to investigate whether and how a transcriptional signal, Bone Morphogenetic Protein signaling, drives a cell migration, centripetal migration. The migrating cells, centripetal follicle cells, consist of two subsets of cells, “leading” and “following” centripetal follicle cells, that although adjacent to each other, migrate differently. The differences in modes of migration correlate to differential gene expression in the centripetal follicle cells. The leading centripetal follicle …

Functional Coordination Of Bet Family Proteins Underlies Altered Transcription Associated With Memory Impairment In Fragile X Syndrome, Seung Kyoon Kim, Xihui Liu, Jongmin Park, Dahun Um, Gokhul Kilaru, Cheng Ming Chiang, Mingon Kang, Kimberly M. Huber, Keunsoo Kang, Tae Kyung Kim

Computer Science Faculty Research

Bromodomain and extraterminal proteins (BET) are epigenetic readers that play critical roles in gene regulation. Pharmacologic inhibition of the bromodomain present in all BET family members is a promising therapeutic strategy for various diseases, but its impact on individual family members has not been well understood. Using a transcriptional induction paradigm in neurons, we have systematically demonstrated that three major BET family proteins (BRD2/3/4) participated in transcription with different recruitment kinetics, interdependency, and sensitivity to a bromodomain inhibitor, JQ1. In a mouse model of fragile X syndrome (FXS), BRD2/3 and BRD4 showed oppositely altered expression and chromatin binding, correlating with …

Understanding The Role Of Ano1 In Oral Cancer, Mallary Forrest

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2008, the gene ANO1 was discovered to encode a calcium activated chloride channel. This gene is located on the 11q13 locus, a locus that is commonly amplified in many cancers including cancer of the head and neck. ANO1 is situated in close proximity to genes associated with growth and apoptosis. As rapid proliferation and lack of apoptosis are hallmark characteristics of cancer, growth factors and apoptosis mediators are expected to be altered in cancer. But what does a calcium activated chloride channel have to contribute to cancer’s pathogenesis? Is it an active gene in cancer progression or is it …

The Role Of Nutrition And Hormone Signaling In Extended Larval Development And Obesity In Starvation-Selected Drosophila Melanogaster, Jennifer M. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Brief periods of starvation are a common stressor that most animals encounter in the wild and must be able to survive in order to maximize their fitness. Starvation resistance of the adult fruit fly, Drosophila melanogaster, is thought to be primarily conferred by adult fat stores, body size, metabolic rate, behavior, and activity levels. Additionally, flies selected for starvation resistance also often show delayed pupariation, which is usually indicative of altered hormone signaling. How starvation selection extends development and if it contributes to adult starvation resistance remains incompletely studied. Identifying the targets of starvation selection that cause extended development and …

Effects Of Curcumin And Its Different Formulations In Preclinical And Clinical Studies Of Peripheral Neuropathic And Postoperative Pain: A Comprehensive Review, Paramita Basu, Camelia Maier, Arpita Basu

Kinesiology and Nutrition Sciences Faculty Research

Lesion or disease of the somatosensory system leads to the development of neuropathic pain. Peripheral neuropathic pain encompasses damage or injury of the peripheral nervous system. On the other hand, 10–15% of individuals suffer from acute postoperative pain followed by persistent pain after undergoing surgeries. Antidepressants, anticonvulsants, baclofen, and clonidine are used to treat peripheral neuropathy, whereas opioids are used to treat postoperative pain. The negative effects associated with these drugs emphasize the search for alternative therapeutics with better efficacy and fewer side effects. Curcumin, a polyphenol isolated from the roots of Curcuma longa, possesses antibacterial, antioxidant, and anti-inflammatory properties. …

Vitamin D3 Induces Mesenchymal-To-Endothelial Transition And Promotes A Proangiogenic Niche Through Igf-1 Signaling, Lei Chen, Anweshan Samanta, Lin Zhao, Nathaniel R. Dudley, Tanner Buehler, Robert J. Vincent, Jeryl Hauptman, Magdy Girgis, Buddhadeb Dawn

School of Medicine Faculty Research

Biological Sciences; Physiology; Molecular Biology; Cell Biology

Rasagiline Effects On Glucose Metabolism, Cognition, And Tau In Alzheimer’S Dementia, Dawn C. Matthews, Aaron Ritter, Ronald G. Thomas, Randolph D. Andrews, Ana S. Lukic, Carolyn Revta, Jefferson W. Kinney, Babak Tousi, James B. Leverenz, Howard Fillit, Kate Zhong, Howard H. Feldman, Jeffrey Cummings

Integrated Health Sciences Faculty Research

Background: A Phase II proof of concept (POC) randomized clinical trial was conducted to evaluate the effects of rasagiline, a monoamine oxidase B (MAO-B) inhibitor approved for Parkinson disease, in mild to moderate Alzheimer's disease (AD). The primary objective was to determine if 1 mg of rasagiline daily for 24 weeks is associated with improved regional brain metabolism (fluorodeoxyglucose–positron emission tomography [FDG-PET]) compared to placebo. Secondary objectives included measurement of effects on tau PET and evaluation of directional consistency of clinical end points. Methods: This was a double-blind, parallel group, placebo-controlled, community-based, three-site trial of 50 participants randomized 1:1 to …

Using Novel Mouse Knockout Models To Study The Roles Of Asm (Acid Sphingomyelinase) In The Regulation Of Multiple Stem Cell Compartments In Vivo, Amro Abdalla

UNLV Theses, Dissertations, Professional Papers, and Capstones

Acid Sphingomyelinase (ASM) is a lipid-modifying enzyme that breaks down sphingomyelin lipids into ceramide and phosphorylcholine. Genetic mutations in the human ASM gene leads to Niemann pick diseases (NPD) type A & B. In NPD type A, patients die between 1-2 years old due to severe neurological complications, while NPD type B patients live to adulthood but suffer from severe visceral organ complications. Type A is usually associated with complete inactivation of the ASM gene. The hallmark of NPD is Purkinje neuron (PN) death. PNs, the major neurons in the cerebellum part of the brain, regulate the balance and fine …

Transcriptional Control Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri, Joy Asami Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

Shigella species, the causal agents of bacillary dysentery, use a type III secretion system (T3SS) to inject two waves of virulence proteins, known as effectors, into the human colonic epithelium to subvert host cell machinery. Transcriptional regulation of these virulence genes is controlled by the three-tiered VirF/VirB/MxiE signaling cascade. Of these, VirB has the largest regulon (~50 genes); however, VirB regulatory properties are poorly understood. To date, VirB is known to function to counter or 'anti-silence' transcriptional silencing mediated by the histone-like nucleoid structuring protein H-NS. To better understand VirB regulation, my colleagues and I chose to better define the …

In Vivo Biosynthesis Of Inorganic Nanomaterials Using Eukaryotes - A Review, Ashiqur Rahman, Julia Lin, Francisco E. Jaramillo, Dennis A. Bazylinski, Clayton Jeffryes, Si Amar Dahoumane

Life Sciences Faculty Research

Bionanotechnology, the use of biological resources to produce novel, valuable nanomaterials, has witnessed tremendous developments over the past two decades. This eco-friendly and sustainable approach enables the synthesis of numerous, diverse types of useful nanomaterials for many medical, commercial, and scientific applications. Countless reviews describing the biosynthesis of nanomaterials have been published. However, to the best of our knowledge, no review has been exclusively focused on the in vivo biosynthesis of inorganic nanomaterials. Therefore, the present review is dedicated to filling this gap by describing the many different facets of the in vivo biosynthesis of nanoparticles (NPs) using living eukaryotic …

Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Gibbs lab has maintained starvation-selected Drosophila melanogaster for >130 generations. These starvation-selected flies evolved an obese phenotype with a suite of physiological differences compared to control-fed flies. Previous studies have shown that long-term starvation-selected Drosophila contain more lipids, have lower metabolic rates and develop more slowly than controls. This dissertation encompasses 1) Examining the molecular mechanisms contributing to starvation resistance, 2) Functional validation of the candidate plin1 allele, and 3) Rapid physiological and genomic evolution in starvation-selected Drosophila.

Starvation-selected Drosophila survive starvation conditions much longer than control-fed flies. This study took a simple approach to identify possible differences in …

The Perplexing Paradox Of Clostridioides (Clostridium) Difficile Infection (Cdi) - Analysis Of Anti-Germinants As Part Of Cdi Prophylaxis, Christopher Yip

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides (Clostridium) difficile infections (CDI) have become the leading cause of nosocomial antibiotic-associated diarrhea worldwide. Under normal circumstances, bacteria found in the gastrointestinal tract provide a barrier against C. difficile colonization. Upon antibiotic therapy, the protective barrier is lost as the microbial community becomes depleted thus providing the opportunity for C. difficile to colonize the human gut. Exposure to taurocholate, a bile acid produced within the mammalian gastrointestinal tract, causes C. difficile spores to begin their transition, a process known as germination, from metabolically dormant structures to toxin-producing cells. As germination is required for the onset of CDI, anti-germination compounds …

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 …

Delineation Of Events In Centripetal Migration During Drosophila Oogenesis, Travis Tait Parsons

UNLV Theses, Dissertations, Professional Papers, and Capstones

All multicellular organisms initially start out as a single cell. This cell must use the genetic information encoded in its DNA to multiply in number and build itself into a complex multicellular organism. How this process occurs is the focus of developmental biology, a field that seeks to understand how a combination of genetic information and environmental conditions shape a cell from its beginnings as a zygote all the way to maturity. A fundamental part of this process is the ability of cells to work together in order to build complex tissues and organs. Cells achieve this coordination by using …

Identifying The Molecular Functions Of The C-Terminal Region Of The Human Proteins, Surbhi Sharma

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Carboxyl (C-) terminus of proteins is usually disordered and flexible allowing proteins to engage in an induced-fit type of interactions with other molecules. Often, these interactions are mediated through the C- terminal minimotifs, which are peptide sequences of 2-15 contiguous residues found in a protein with a known molecular function. These functions include protein binding, trafficking, and post-translational modifications. In this dissertation, we investigated how many human proteins contain the C-terminal minimotifs. We cataloged 3,593 previously verified C-terminal minimotifs representing 17% of the human proteome. Based on these observations, we asked: Does the remaining 83% of the human proteome …

Transcriptional Silencing And Anti-Silencing Of Virulence Genes In The Bacterial Pathogen Shigella Flexneri: Virb, Dna Supercoiling, And The Histone-Like Nucleoid Structuring Protein, Michael Adam Picker

UNLV Theses, Dissertations, Professional Papers, and Capstones

Transcriptional silencing and anti-silencing affect many aspects of bacterial physiology, including virulence in bacterial pathogens. In Shigella species, a group of gram-negative pathogens that cause bacillary dysentery in humans, the histone-like nucleoid structuring protein (H-NS) transcriptionally silences virulence genes found on the large virulence plasmid while VirB anti-silences these genes. However, the mechanistic details of their interplay are not fully understood. To elucidate their regulatory mechanisms, I use the icsP virulence locus, which shares a long intergenic region with the divergently transcribed ospZ gene (1535 bp from TSS to TSS). Prior to this work, two discrete H-NS binding regions had …