Biochemistry, Biophysics, and Structural Biology Commons^™

The Neuroprotective Effect Of Cdc42 Inhibition In The G93a Mutant Hsod1 Mouse Model Of Als, Andrea Koly

Undergraduate Theses, Capstones, and Recitals

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal neurodegenerative disease characterized by the selective loss of upper and lower motor neurons, leading to muscle weakness, neuromuscular junction (NMJ) degeneration, paralysis, and eventual death due to respiratory failure. Despite extensive research, effective disease-modifying therapies remain limited, underscoring the need to identify novel molecular targets involved in ALS pathogenesis. Dysregulation of Rho family GTPases has been implicated in neurodegeneration, with Rac and Rho exerting opposing effects on neuronal survival; however, the role of the closely related GTPase Cdc42 remains poorly understood in ALS. In this study, the therapeutic potential of inhibiting …

A Computational Micropatterning Approach To Study Caveolae And Protein Localization In Vascular Biology, Andrew B. Grespin

Electronic Theses and Dissertations

Caveolae are specialized, flask-shaped membrane invaginations highly expressed in endothelium and dysregulated in atherosclerosis. Caveolae play a central role in buffering membrane tension, yet the principles governing their spatial organization remain elusive. Thus, we sought to generate the most comprehensive and systematic analysis of blood vessel caveolar spatial organization. However, cell culturing, the backbone of human-focused biological research, does not standardly do well to model physiologically relevant cell behaviors such as migration or polarity-based tissue formation, particularly for punctate proteins and structures like caveolae. Micropatterns are cell-adhesive shapes that biophysically confine cell(s) to a user defined geometry which stereotype organelle …

Contribution Of G4 Structure To Alzheimer’S Disease And Tau Pathology, Lena Michaela Kallweit

Electronic Theses and Dissertations

The occurrence of Alzheimer’s Disease (AD) is rapidly increasing as our global population ages. With the majority of therapeutic drugs in the last couple of decades failing clinical trials, new molecular targets are needed to combat the expected influx of new AD cases. AD pathogenesis is associated with abnormal protein aggregation, characterized in part by intracellular accumulation of hyperphosphorylated tau (p-tau) in neurofibrillary tangles (NFTs). RNA has been identified as a major non-proteinaceous component of NFTs and has been implicated as an active cofactor in tau aggregation and spread. Recent work has shown that aggregates from AD brains contain almost …

Self-Assembling Rna Nanostructures Are Highly Sensitive To Environmental Conditions, Jordan Aposhian, Surya Pratap S. Deopa, Scott Horowitz, Joseph D. Yesselman

Chemistry and Biochemistry: Faculty Scholarship

Recent developments in RNA nanotechnology have led to an increase in the design of specific, higher-order RNA structures, which will ultimately be used in drug delivery and immunomodulation applications. As researchers create RNA nanostructures with the intention of making them a standard tool in molecular biologists' toolkits, further investigation is required into the robustness of RNA designs. Primarily, in what different molecular contexts are the designed and intended nanostructures stable? In this work, we show that RNA nanostructure self-assembly is highly sensitive to environmental conditions by using second-order right-angle light scattering. While a test RNA hexagonal grid nanostructure forms correctly …

Role Of Nucleic Acids As Chaperones In Protein Folding, Zijue Huang

Electronic Theses and Dissertations

Many proteins have slow folding times in vitro that are physiologically untenable. To combat this challenge, ATP-dependent chaperonins are thought to possess the unique ability to catalyze protein folding. Performing quantitative model selection using protein folding and unfolding data, we here show that short nucleic acids containing Gquadruplex (G4) structure can also catalyze protein folding. Performing the experiments as a function of temperature demonstrates that the G4 reshapes the underlying driving forces of protein folding. To understand the structural basis of this catalytic activity, we introduce NMR method to solve the structures, at base-level resolution, of a multiconformer G4 with …

Centrosomal And Non-Centrosomal Microtubule Networks Coordinate To Drive Nuclear Dynamics In Developing Epithelium, Rashmi Budhathoki

Electronic Theses and Dissertations

The morphogenesis of developing tissues relies on extensive cellular rearrangements in shape, position, and identity. A key process in reshaping tissues is cell intercalation-driven elongation, where epithelial cells align and intercalate along a common axis. Typically, analyses focus on how peripheral cortical forces influence cell shape changes. Less attention is given to how inhomogeneities in internal structures, particularly the nucleus, impact cell shaping. Here, we examine how pulsed contractile and extension dynamics interact with the nucleus in elongating Drosophila embryos. Our data show that tightly packed nuclei in apical layers hinder tissue remodeling/oscillatory behaviors. We identify two mechanisms for resolving …

Du Undergraduate Showcase Abstracts: Research, Scholarship, And Creative Works, Kabe Aberle, Nadia Kako, Kateri Mcrae, Brooke Agulnek, Sky Palmon, Yasmine Ramirez, Francisca Aguirre Beltran, Ashley Juarez, Bridget Kim, Tessa Appel, Sterling Kerr, Spencer Ingley, Gabe Meyer, Robin Tinghitella, Dale Broder, Lily Baeza, Chloe Beers, Julia Coakley, Whitney Kelsey, Sydney Gainforth, Gabi Wing, Audrey Martin, Aaliyah Amore Berry, Brooke Watley, Kiruthika Venkatesan, Rachel Bienstock, Annabella Brotherston, Madison Bryant, Mia Burgener, Emma P. Lieb, Rachel A. Johnson, Jennifer L. Hoffman, Kania Campbell, Kiena Campbell, Courtney Cassidy, Sage Krzyzkowski, Maddox Jones, Skylar Abookire, Luke Hawkins, Sunnah Yoon, Andrea Chu, Yan Qin, Nyah Cubbison, Brian Gearity, Daniel Mcintosh, Mariely Cruz, Edward Garrido, Grady Dionne, Nicole Doris, Lyndsie Salvagio, Ann-Charlotte Granholm-Bentley, Anna Dymov, Hannah Eckert, Gabrielle Welsh, Erica Larson, Charlie Ernst, Anna Zhou, Sarah Watamura, Larissa Fedorovich-Klein, Georgie Fields, Kimberly A. Guevara, Aven Mccall, Ben Peltier, Feruz Yahia, Patrick Flores, Jadyn Floyd, Sophia Forcier, J. Von R. Monteza, Peter Sokol-Hessner, Gwendolyn Geiger, Scott Nichols, Camryn Gunter, Kendal Hengst, Charlie Bednarz, Issy Garside, Addison Baker, Rachel Mina, Brooke Hermanson, Amanda Klingler, William Highfill, Sydney Jaques, Kerstin Lewey, Allison Grossery, Daniel Linseman, Ethan Lim, Jagger Livengood, Owen Mantelli, Gabby Pappas, Abby Mcdonald, Madeleine Dierking, Eve Miller, Emma Loeber, Anna Marlow, Michael Kerwin, Ella Mathews, Hillary Hamann, Khadija Mohamed, Vivian Nguyen, Gabri Notov, Ifunayachi Ogbonna-Ukuku, Sunil Kumar, Charles Baysah, Sarah Olson, Don Sullivan, Anna Paradiso, Jay Parrish, Mira Pronobis, Alisha Pravasi, Kerstin Haring, Diego Ramirez, Christopher Reardon, Juliana Ramirez, Casey Doherty, Ella Kestner, Teagan Weindel, Cate Billings, Pablo Torre-Walter, Lucy Rand, Samantha Reynolds, Mark Siemens, Khadeeja Rashid, Laine Satterlee, Piper Heilbronner, Lily Pound, Ben Whitehurst, Anna Respet, Lizzie Lesoing, Sydney Hertel, Aya Saad-Masri, Brooke Ballenger, Max Proske, Hannah Rosenberg, Ellia Nakahara, Sophia Espinoza, Ivan Woolhouse, Simon Ruland, Gorkem Er, Timothy Sweeny, Melaku Saketa, Michela Schenk, Maren Lynch, Madi Hamm, Grace Schroeder, Michelle Rozenman, Rana Seif, Jackson Hall, Marisela Simental, Daniel Paredes, Aaron Mena, Preston Spaan, Evelyn Stovin, David Andrew Swartz, Anh Tran, Daniel Pittman, Luke Farchione, Emily Boyer, Ukari Verner, Lacey Conrad, Jonathan Velotta, James Weiner, Jagger Gossett, Noah Sherry, Sam Proud, Ben Block, Avi Narayana, Zoey Weiss, Alyssa Wilson, Gabrielle Walsh, David Zonana, Keely Wright, Kena Riveria, Lillybelle Deer, Jena Doom, Elysia Davis, Isabelle Yaremenko, Caitlyn Young

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Research Showcase.

Microscopic Nucleic Acid-To-Protein Ratio: A Label-Free Approach For Pancreatic Cancer Detection, Sky Gao, Keerthi Priya Jangili, Alfred Akinlalu, Emmanuel Ogberefor, Tommy Gao, Kalpana Devaraj, Dali Sun

Electrical and Computer Engineering: Faculty Scholarship

Accurate and timely diagnosis remains a major clinical challenge, hindered by the limitations of conventional histopathological methods, which often rely on labor-intensive staining protocols and subjective interpretation by specialized pathologists. These methods can fail to capture the full molecular and phenotypic heterogeneity of tumors, leading to increased diagnostic time, cost, and variability. To overcome these challenges, we developed a novel label-free ultraviolet (UV) microscopic imaging technique that exploits the intrinsic optical absorption properties of cellular nucleic acids and proteins. By modifying standard brightfield microscopes, our approach quantitatively measures the nucleic acid-to-protein ratio (NPr), enabling high-resolution visualization and discrimination between malignant …

Analysis Of Synaptotagmin Isoforms In Lßt2 Gonadotrophs, Caitlin Vahl

Undergraduate Theses, Capstones, and Recitals

The anterior pituitary is comprised of five cell types which secrete regulatory hormones into the bloodstream. Specifically, gonadotrophs synthesize and release sex hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in response to gonadotropin-releasing hormone (GnRH). GnRH signals from the hypothalamus regulate the differential secretion of LH and FSH from the anterior pituitary. Exocytosis of FSH and LH from dense core vesicles (DCVs) occurs in response to an intracellular calcium signal, sensed by the synaptotagmins proteins. Various isoforms of synaptotagmins exist and each isoform has varying affinity for calcium, causing calcium-regulated exocytosis to be finely controlled. Because LH and FSH …

Photochemistry Of Quinones And Combustion-Derived Particles, Desiree J. Sarmiento

Electronic Theses and Dissertations

Quinones are ubiquitous species that can be produced from the photochemical aging of combustion-derived particles (CDPs). Polycyclic aromatic hydrocarbons (PAHs) are a major component of CDPs and are precursors to quinones and other oxidized products (OPAHs). My work first expanded on the PAH and OPAH photochemistry research of Dr. John Haynes, who showed that anthracene (ANT) oxidizes into 1,4-naphthoquinone (1,4-NAPQ), 1,4-anthraquinone (1,4-ANTQ), and 9,10-anthraquinone (9,10-ANTQ), and of Dr. Heather Runberg, who demonstrated the ability of ANT and these quinones to generate reactive oxygen species (ROS). Then at the Pacific Northwest National Laboratory (PNNL), I was given the opportunity to investigate …

Foldit Education Mode, Brett Schulz

Electronic Theses and Dissertations

Foldit education mode is a puzzle campaign within the protein folding video game Foldit. Education mode, initially designed as a classroom supplement for undergraduate biochemistry courses, has been expanded to provide a more comprehensive learning tool to players without a background in biochemistry. The edited and added levels teach players about protein biochemistry through playing puzzles designed to convey information and gameplay mechanics. The new Foldit education mode campaign features 49 levels grouped into 11 categories. The campaign has 6 new levels designed specifically for education mode and 4 levels adapted from the traditional Foldit campaign for use within education …

Carbon Monoxide Releasing Polymeric Micelles, Riya Joshi

Electronic Theses and Dissertations

Carbon monoxide (CO), traditionally known as a toxic gas, has emerged as a potential therapeutic agent due to its cytoprotective, anti-inflammatory, and vasodilatory properties. This study explores the development of CO-releasing polymeric micelles as a controlled delivery system for biomedical applications. Using ring-opening metathesis polymerization (ROMP), we synthesized diblock copolymers incorporating CO-releasing moiety diphenylcyclopropenone (DPCP) with hydrophilic polyethylene glycol (PEG) to enhance solubility and stability of the overall CO releasing system. Dynamic light scattering (DLS) and electron microscopy (EM) confirmed the formation of well-defined micelles, while fluorescence assays demonstrated efficient CO release with the use of Iridium photocatalyst under 470 …

Development, Optimization, And Validation Of A High-Sensitivity Capillary Zone Electrophoresis System For Bioanalytical Applications, Aaron I. Mena

Electronic Theses and Dissertations

Capillary zone electrophoresis (CZE) is a powerful analytical technique widely used for biomolecular separation due to its high resolution, efficiency, and sensitivity. This report presents the development and validation of a novel CZE system designed to improve modularity, reproducibility, and operational efficiency. The system integrates a laser-induced fluorescence (LIF) detection method with a 488 nm laser, enhanced fluid control through a negative pressure system, and a user-friendly GUI for automated operation and data acquisition. Performance verification included pressure stability tests, fluorescence accuracy assessments, and electrophoretic reproducibility studies. Comparative analysis with a previous CZE iteration confirmed improved baseline stability, peak resolution, …

Synthetic Protein Mimetic Based Therapies For Neurodegeneration, Nicholas H. Stillman

Electronic Theses and Dissertations

Protein-protein interactions (PPIs) are crucial for the regulation of a majority of, if not every fundamental cellular process. Despite their role in regular biological processes, dysregulated and/or aberrant protein-protein interactions (aPPIs) are often related to the onset of disease including cancer, viral infection, and amyloid diseases. aPPIs have historically been deemed ‘undruggable’ due to their large surface area and lack of a binding cavity; however, today, more than 40 disease-related aPPIs have been targeted with small molecules and several of those have reached clinical trials.

A class of synthetic protein mimetics called oligopyridylamides (OPs) has been shown to inhibit disease-related …

Dysfunction Of Polyamine Metabolism In Down Syndrome Related To Cellular Senescence And Β-Amyloid Production, Andres D. Sola

Electronic Theses and Dissertations

Polyamines (PA) are ubiquitous in cells and highly involved in several important cellular functions and thus the dysregulation of their biosynthetic pathway is potentially associated with the progression of age-related diseases like Alzheimer’s’ disease (AD). Though there is research describing how PA content changes in organisms as they age or in those experiencing rapid aging from increased rates of senescence, as in Down syndrome (DS), it is not clear how this connection occurs and whether modulating this pathway may reveal downstream effects on related disease progression. This study examines how the modulation of the PA biosynthetic pathway by inhibition of …

Investigating The Role Of Tetherin Protein In Multivesicular Bodies Fusions In Lung Cancer Cells, Md. Rakib Miah

Electronic Theses and Dissertations

Cells rely on the secretion of exosomes to communicate with one another and this process is potentially mediated by a protein called tetherin, which anchors exosomes to the cell surface to limit their spread. Tetherin protein has attracted a lot of attention because of its capacity to hinder the propagation of viruses by attaching virions to the surface of host cells. Treatment with interferon-alpha (IFNα) increases the production of tetherin, although it is not known how this affects tetherin localization and exosome-mediated communication. This thesis looks at how the expression of tetherin, which IFNα boosts, affects the dynamics of intercellular …

Phagolysosomes Break Down The Membrane Of A Non-Apoptotic Corpse Independent Of Macroautophagy, Shruti Kolli, Cassidy J. Kline, Kimya M. Rad, Ann M. Wehman

Biological Sciences: Faculty Scholarship

Cell corpses must be cleared in an efficient manner to maintain tissue homeostasis and regulate immune responses. Ubiquitin-like Atg8/LC3 family proteins promote the degradation of membranes and internal cargo during both macroautophagy and corpse clearance, raising the question how macroautophagy contributes to corpse clearance. Studying the clearance of non-apoptotic dying polar bodies in Caenorhabditis elegans embryos, we show that the LC3 ortholog LGG-2 is enriched inside the polar body phagolysosome independent of autophagosome formation. We demonstrate that ATG-16.1 and ATG-16.2, which promote membrane association of lipidated Atg8/LC3 proteins, redundantly promote polar body membrane breakdown in phagolysosomes independent of their role …

Characterizing Biomolecular Structure Features Through An Innovative Elliptical Dichroism Spectrometry For Cancer Detection, Yusuf Asad, Keerthi Priya Jangili, Amara Arshad, Maliha Elma, Komila Rasuleva, Alfred Akinlalu, Tommy Gao, Umamaheswara Rao Tida, Wenjie Xia, Dali Sun

Electrical and Computer Engineering: Faculty Scholarship

This research introduces a novel method for evaluating the structural features of biomolecules, utilizing our innovative Elliptical Dichroism (ED) spectrometer specifically designed for stereochemical analysis. By integrating ED spectrometry with autocorrelation (AC) analysis, we investigate the conformational characteristics of biological molecules such as amino acids, proteins, and extracellular vesicles (EVs) induced by elliptically polarized UV absorption. Our streamlined approach offers a cost-effective and portable solution with minimal sample consumption and supports multiple working modes to efficiently characterize biomolecular structures. The insight from this new approach demonstrates potential applications in using biomolecular characterization for cancer detection.

Unraveling The Role Of Hid-1: Insights Into Sgii Regulation, Breanna L. Sellers

Electronic Theses and Dissertations

The regulated secretory pathway is important for the secretion of hormones and neuropeptides from large dense core vesicles (LDCVs). Dysregulation of the biogenesis of LDCVs can result in metabolic and neurological diseases. Recent studies have suggested that the peripheral membrane protein HID-1 plays a role in the sorting and storage of granins which contribute to LDCV biogenesis. To further understand how HID-1 influences the regulation of granins, we investigated potential HID-1 interactors. We determined that while HID-1 is likely functioning in the same pathway as USP25, a deubiquitinating enzyme (DUB), the cause of reduced cellular SgII levels is likely not …

Sequence Specificity Of Non-Structural Protein 15 From Sars-Cov-2, John Vincent Mcguire

Electronic Theses and Dissertations

The SARS-CoV-2 virus was recently able to cause a global pandemic, largely due to the asymptomatic period that occurs during initial infection. During this period, patients are infectious but do not exhibit symptoms, resulting in the unintentional spread of the virus. This occurs because the virus effectively avoids detection by the immune system during the early stages of infection, and as symptoms are the result of immune system activation, they never manifest. Non-structural Protein 15 (Nsp15) is one of the tools the virus uses to remain undetected, via its degradation of Pathogen-Associated Molecular Patterns (PAMPs) that would otherwise be recognized …

The Role Of Edc3 In Drosophila Melanogaster Neuronal Development, Keelan Zius

Electronic Theses and Dissertations

Enhancer of mRNA-decay 3 (Edc3) is a component of multiple decapping complexes that regulates the transcriptome by targeting a subset of transcripts for decapping for 5’-to-3’ messenger RNA (mRNA) decay. A missense mutation in the conserved Lsm domain of Edc3 has been reported in two siblings presenting with mild, non-syndromic intellectual disability (ID), however, the role of Edc3 is neuronal development has never been evaluated. Here, we use the Drosophila melanogaster model system to investigate the effects of Edc3 disruption on neuronal development. We found Edc3 reduction leads to significant hyperplasia at the larval neuromuscular junction (NMJ), providing the first …

Colocalization Of Odc And Amyloid Plaques In Patients With Alzheimer’S Disease And Down Syndrome, Julia S. Gielczynski

Undergraduate Theses, Capstones, and Recitals

Polyamines, and their rate-limiting enzyme ornithine decarboxylase (ODC), are crucial for many functions in the central nervous system but levels decrease with age. In neurodegenerative diseases, like Alzheimer’s Disease (AD), polyamine levels begin to increase again. Yet, there are still many unanswered questions surrounding polyamine’s possible role in AD, especially in those with Down Syndrome (DS), who also have an extra copy of the amyloid precursor protein (APP) and tend to get AD far earlier than the general population. We aim to investigate if there is colocalization between amyloid plaques and Ornithine Decarboxylase (ODC) in patients with AD and AD/DS, …

Characterization Of Oxidized Tau Protein Aggregation And Inhibition Of Tau Aggregation Via Map2, Brad Krzesinski

Electronic Theses and Dissertations

Neurofibrillary tangles (NFT) composed of the microtubule stabilizing protein Tau are a pathological hallmark of Alzheimer's disease (AD) and many other dementia related diseases specified as Tauopathies. Due to alternative mRNA splicing, intrinsically disordered Tau exists as six separate isoforms in the adult human brain where they are categorized by the lack or inclusion of the second repeat in the microtubule binding domain (3R or 4R respectively). Isoforms are subcategorized by the inclusion or lack thereof, one or two N-terminal inserts. Many studies show that Tau aggregates into amyloid fibrils and these fibrils can break into small oligomeric units known …

Morphological Remodeling Of The Endoplasmic Reticulum During Mitosis And Its Influence On The Integrity Of The Spindle Apparatus, Katie R. Rollins

Electronic Theses and Dissertations

The Endoplasmic Reticulum (ER) is the largest organelle in the cell by surface area and forms contacts with other organelles throughout the cell. In recent work, the ER has been implicated in numerous processes within the cell beyond its canonical roles of protein synthesis and calcium storage. The ER also undergoes a remarkable transition in morphology during cell division, with mitotic divisions requiring a massive remodeling of various membranous organelles such as the nuclear envelope and Golgi. However, whether changes in ER behaviors modulate mitotic events is less clear. The rapid cleavage divisions in the early Drosophila embryo are a …

Du Undergraduate Showcase Abstracts: Research, Scholarship, And Creative Works, August Alexander, Kevin Summers, E. Paige Lloyd, Alyssa Aragon, Lauren Wols, Erica Larson, Colton Arciniaga, Lily Baeza, Ellie Barnett-Cashman, Sidney Barbier, Maverick Bartholomew, Ryan Bell, Trevor Briggs, Amanda Brown, Cory Marchi, Maddy Pontius, Jennifer Gallagher, Claire Kwok, Channing Bullock, Alex Mccollister, Kim Gorgens, Daniela Chavez, Yamilet Espinoza Nuñez, Giovanni Valladares Giron, William Christensen, Olivia Kachulis, Daniel Cierasynski, Brandon Cohen, Spenser Dobbs, Lindsay Goolsby, Noah Craver, Nyah Cubbison, Liam Doherty, Nicole Doris, Yan Qin, Alexander Nguyen, Lily Harmon, Shubh Todi, Naichen Zhao, Noah Fagello, Stacia Fritz, Paola Gascot-Chinea, Alex Volkova, Janelyn Geronimo, Elsie Harrington, Shane Simmons, Clarice Hise, Laura Moreno Palmer, Henry Xu, Yesu Leela Pasupula, Emily Fisher, Zachary Hogan, Colin Kleckner, Alyssa Knaus, Erin Kubat, Sam Werkema, Katie Lamberton, Lilliya Larson, Allie Leary, Vanessa Leon-Gamez, James H. Gallagher, E. Dale Broder, Robin M. Tinghitella, Emma Loeber, Alina Mali, Ixchel Marquez, Lauren Mcgrath, Ella Matthews, Grace Naegelen, Audrey Ng, Megan Lucyshyn, Rachel Brough, Alexandra Norman, Joe Ontiveros Rodriguez, Ben Dossett, Ori Miller, Janamejay Sharma, Christopher Reardon, Vincent Pandey, Regan Parish, Ren Pratt, Alisha Pravasi, Sanchari Das, Cari Reichel, Emma Robson, Victoria Rockwell, Jayce Rumsey, Steven Said, Norah Schroder, Alaina Smith, Shannon Murphy, Shujan A. Sharafeldeen, Stanley M. Kanai, James T. Nichols, David E. Clouthier, Macalia R. Augustus, Daniel Silva Rios, Scott Simpson, Anna Sparling, Chase Spurbeck, Kimberly Chiew, Christine Stadnik-Poteroba, Jacqueline Stephenson, Evelyn Stovin, Mia Supan, Lauren Tapper, Will Thrush, Anna Vogt, Michaela Walheim, Jon Weber, Hunter Whitehouse, Kansas Wood, Hayley Sayre, Lydia Mccann, Maread Mclaughlin, Kelly Krumrie, Olivia Wuttke

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Research Showcase.

Identification Of The Functional Domain Of The Dense Core Vesicle Biogenesis Factor Hid-1, Blake H. Hummer, Theodore Carter, Breanna L. Sellers, Jenna D. Triplett, Cedric S. Asensio

Biological Sciences: Faculty Scholarship

Large dense core vesicles (LDCVs) mediate the regulated release of neuropeptides and peptide hormones. HID-1 is a trans-Golgi network (TGN) localized peripheral membrane protein contributing to LDCV formation. There is no information about HID-1 structure or domain architecture, and thus it remains unknown how HID-1 binds to the TGN and performs its function. We report that the N-terminus of HID-1 mediates membrane binding through a myristoyl group with a polybasic amino acid patch but lacks specificity for the TGN. In addition, we show that the C-terminus serves as the functional domain. Indeed, this isolated domain, when tethered to the TGN, …

Mechanisms Behind The Chaperone Activity Of Nucleic Acids, Theodore J. Litberg

Electronic Theses and Dissertations

Understanding the interplay between nucleic acids and protein aggregation is integral to the understanding of proteostasis, aging, and neurodegenerative disease progression. Nucleic acids are known to modulate the aggregation of PrP, tau, ⍺-synuclein, and other disease relevant proteins. Although the interactions between misfolded protein and nucleic acids can play a role in disease, this interaction may potentially be beneficial as well. Our group and others have shown nucleic acids can be powerful chaperones. Previous work has shown both RNA and DNA can prevent protein aggregation and RNA can pass off protein clients to the heat shock protein (Hsp) system. Here …

Polar Body Membrane Breakdown Occurs Independent Of Macroautophagy In C. Elegans, Shruti Kolli

Electronic Theses and Dissertations

Failure to digest cell corpses can lead to lupus-like autoimmune disorders in mammals. To better understand if LC3-associated phagocytosis (LAP) drives cell corpse breakdown in phagolysosomes, we studied the clearance of the C. elegans polar body during embryonic development. ATG16L1 has separable roles in regulating LC3 recruitment during macroautophagy and LAP. We demonstrated that the ATG16L1 C. elegans orthologs, ATG-16.1 and ATG-16.2, function redundantly to promote polar body membrane breakdown. We also discovered that truncating the LAP-specific WD40 domain of ATG-16.2 unexpectedly disrupts autophagy. Furthermore, we confirmed that polar body membrane breakdown occurs independent of macroautophagy. We also showed that …

Investigating The Role Of Tethering In Exosomal Secretion, Zdeněk Otruba

Undergraduate Theses, Capstones, and Recitals

Exosomes are a type of membrane vesicles utilized in intercellular communication. Exosomes are first packaged into larger membrane vesicles called multivesicular bodies (MVBs). When exosomes are secreted, the membrane of the MVBs fuses with the cellular membrane, and then the exosomes are released. Experimental observations suggest that the movement of the exosomes is hindered during this process; they require much longer time to leave the fusion site than they would if they were diffusing freely. A prevalent hypothesis is that the cause of this hindrance is attachment of the exosomes to the cell surface. Recent work suggests that tetherin, a …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works