Biochemistry, Biophysics, and Structural Biology Commons^™

Modeling Functional Connectivity With Learning And Memory In A Mouse Model Of Alzheimer’S Disease, Lindsay Fadel, Elizabeth Hipskind, Steen E Pedersen, Jonathan Romero, Caitlyn Ortiz, Eric Shin, Md Abul Hassan Samee, Robia G Pautler

Faculty, Staff and Students Publications

Introduction: Functional connectivity (FC) is a metric of how different brain regions interact with each other. Although there have been some studies correlating learning and memory with FC, there have not yet been, to date, studies that use machine learning (ML) to explain how FC changes can be used to explain behavior not only in healthy mice, but also in mouse models of Alzheimer's Disease (AD). Here, we investigated changes in FC and their relationship to learning and memory in a mouse model of AD across disease progression.

Methods: We assessed the APP/PS1 mouse model of AD and wild-type controls …

Characterizing The Targeting Of Toc159 Receptors To The Chloroplast Outer Envelope Membrane And Their Role In The Assembly Of Distinct Toc Complexes, Michael Fish

Theses and Dissertations (Comprehensive)

Global agriculture and food security face challenges from climate change, population growth, and other human-driven pressures. Enhancing our understanding of plant biology, particularly chloroplast function, is critical for improving crop yield and stress resilience. As the sites of photosynthesis and key regulators of plant responses to environmental cues, chloroplasts depend on the precise import of thousands of nuclear-encoded proteins to maintain their biogenesis and function. While much is known about the core translocon components in the chloroplast outer envelope membrane that form the TOC complex, the mechanisms underlying their targeting, assembly, and regulation remain incompletely understood.

Plastids, including chloroplasts, evolved …

Reversible Degradation Of Peptidoglycan By Lytic Transglycosylases, Aaron Devereaux

Theses and Dissertations (Comprehensive)

Antimicrobial resistance continues to be a burden on the global healthcare system with an estimated cost of billions of dollars and millions of deaths each year. Recently, there has been little to no development on new antibiotics to treat bacterial infection, and any that are developed become resisted to within a few years. Both Gram-positive and Gram-negative bacteria contain a mesh-like layer called peptidoglycan (PG) that surrounds their cells providing strength, cell shape, and protection from their environments. This layer is a polymer of N-acetylmuramic acid (MurNAc) and N-acetylglucosamine (GlcNAc) connected via a b-1,4-glycosidic bond, with each strand being cross-linked …

Addressing Unprofessional Behaviors In The Clinical Learning Environment: Lessons From A Multi-Year Virtual, Intergenerational, Interdisciplinary Workshop, Stacey Rose, Anita Kusnoor, Phuong Huynh, Jocelyn Greely, Yesenia Rojas-Khalil, Doris Kung, Anne Gill, Nadia Ismail, Nital Appelbaum

Faculty, Staff and Students Publications

INTRODUCTION: Optimizing the clinical learning environment (CLE) is a medical education priority nationwide.

MATERIALS AND METHODS: We developed a virtual, one-hour workshop engaging students, housestaff and faculty in small-group discussions of five case scenarios adapted from reported unprofessional behaviors in the CLE, plus didactics regarding mistreatment, microaggressions and bystander interventions.

RESULTS: Over two sessions (2021-2022), we engaged 340 students and 73 faculty/housestaff facilitators. Post-session surveys showed significant improvement in participants' ability to recognize and respond to challenges in the CLE.

DISCUSSION: Our innovative workshop, including scenarios derived from institutional reports of unprofessional behaviors, advanced participants' knowledge and commitment to improve …

Interactions Of The Sars-Cov-2 Viral Genome 3’-Untranslated Region With Viral And Host Rnas, Caleb Frye, Mihaela Rita Mihailescu

Electronic Theses and Dissertations

This dissertation focuses on the characterization of RNA-RNA interactions within the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome and with host microRNAs. As the causative agent of coronavirus disease 2019 (COVID-19), SARS-CoV-2 has evolved rapidly since its appearance. This has warranted prompt characterization of the virus particularly of its single stranded RNA (ssRNA) genome. By using a combination of bioinformatics, biophysics, and/or biological assays, we analyzed the SARS-CoV-2 viral genomic RNA and uncovered interactions of genomic RNA with host RNAs, highlighting an underutilized method of targeting RNA viruses. We showed here that the conserved elements in the viral genomic …

Investigating The Expression Of C-Myc And Birc5 In Trail And Pbox-15 Treated Metastatic Prostate Cancer Cells, Corinne Kai Leng Chew, Hannah O'Toole, Daniela M. Zisterer, Seema M. Nathwani, Jade K. Pollock

SURE Journal: Science Undergraduate Research Experience Journal

Purpose Metastatic prostate cancer is associated with poor survival rate and limited treatment options. Overexpression of c-Myc and BIRC5 has been reported in prostate cancer cells which contribute to the development of the tumour environment. The specific tumour receptor mechanism of the death ligand TRAIL (tumour necrosis factor related apoptosis inducing ligand) has attracted remarkable therapeutic interest. However, many cancer cells are resistant to TRAIL monotherapy. A novel microtubule-targeting agent, PBOX-15 is known to exhibit anti-tumour activity in cancer cell lines including those with multi-drug resistance. Previous studies demonstrated that PBOX-15 is capable in sensitising cancer cells to TRAIL-mediated cell …

Comparing Multivalent Cross-Linked Sodium Alginate/ Montmorillonite Beads Containing Curcumin Or Cayenne Pepper As Drug Carriers And Their Antimicrobial Resistance, Shionainn Traynor, Shubham Sharma

SURE Journal: Science Undergraduate Research Experience Journal

The aim of the following work was to investigate and compare curcumin and cayenne pepper in microbeads composed of sodium alginate (SA) crosslinked with montmorillonite (MMT) to act as drug carriers and their antimicrobial resistance. The microbeads were prepared through ion-exchange in multivalent solutions of CaCl₂, MgCl₂ and AlCl₃. The microbeads were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX) and the time required for intercalation of curcumin and cayenne pepper with MMT. Simulated intestinal fluid (pH 7.3) and gastric fluid (pH 1.2) at 37°C were used for comparison in swelling studies. …

Editorial - Sure Journal Vol 6, Anne M. Friel, Eva Campion, Sinead Loughran

SURE Journal: Science Undergraduate Research Experience Journal

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Development Of Novel Nanocarriers With Multi Modal Action Against Lung Cancer, Gayathri K

Theses and Dissertations

Lung cancer ranks among the top causes of cancer-related deaths worldwide. The deteriorating environment and unhealthy lifestyle in the modern era has further contributed to the exponential increase in lung cancer incidence across the globe. Lung cancers fall under two major types based on the location of the tumour in the lung namely, small-cell lung cancer (SCLC) which is more aggressive, and non-small-cell lung cancer (NSCLC) which is more prevalent. Late diagnosis has been a major cause for poor prognosis as the cancer is detected only in an advanced stage.

Conventional therapies like chemotherapy, surgery and radiotherapy against lung cancer …

Simple Improvements In Vector Design Afford Substantial Gains In Aav Delivery Of Aggregation-Slowing Aβ Variants, Ella Borgenheimer, Cameron Trueblood, Bryan L Nguyen, William R Lagor, Joanna L Jankowsky

Faculty, Staff and Students Publications

Adeno-associated virus (AAV) gene therapy for neurological disease has gained traction due to stunning advances in capsid evolution for CNS targeting. With AAV brain delivery now in focus, conventional improvements in viral expression vectors offer a complementary route for optimizing gene delivery. We previously introduced a novel AAV gene therapy to slow amyloid aggregation in the brain based on neuronal release of an Aβ sequence variant that inhibited fibrilization of wild-type Aβ. Here we explore three coding elements of the virally delivered DNA plasmid in an effort to maximize the production of therapeutic peptide in the brain. We demonstrate that …

A Multiplex Metabolomic Approach For Quality Control Of Spirulina Supplement And Its Allied Microalgae (Amphora & Chlorella) Assisted By Chemometrics And Molecular Networking, Nesrine Hegazi, Amira R. Khattab, Hamada H. Saad, Bishoy Abib, Mohamed A. Farag

Faculty Journal Articles

Microalgae species are of economic importance regarded as “green gold” being rich in bioactive compounds. Spirulina and Chlorella are the most popular microalgal species and are marketed as healthy food supplements. At the same time, Amphora holds potential as a source of healthy lipids and essential fatty acids. Yet, there are considerable variations in their reported chemical composition, and less is known about their compositional differences. A multiplexed metabolomic approach was adopted for the quality control (QC) of Spirulina supplements and to compare its constitutive metabolome to Chlorella and Amphora. The adopted protocol comprised gas chromatography-mass spectrometry (GC–MS), ultra-high performance …

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 …

Soil Organic Matter Processes From The Treetops To The Clay Particle: The Role Of Climate, Minerals, And Organic Matter Chemistry In Soil Carbon Accumulation And Stability, Jessica G. Murray

All Graduate Theses and Dissertations, Fall 2023 to Present

Soils store more carbon than plants and the atmosphere, yet release ten times more carbon dioxide (CO₂) to the atmosphere than human activities each year. Small shifts in the balance of soil carbon storage and soil carbon emissions could make climate change less severe, by acting as a sink for the carbon plants pull from the atmosphere, or make climate change worse, by releasing even more planet-warming greenhouse gases. The processes governing whether soils store or release carbon depend on tiny soil microorganisms which convert plant carbon to soil organic matter, releasing CO₂ in the process. In …

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 …

Going Against The Family: Perturbation Of A Greenbeard Pathway Leads To Falsebeard Cheating, Peter Lehmann, Mariko Katoh-Kurasawa, Peter Kundert, Gad Shaulsky

Faculty, Staff and Students Publications

Greenbeards facilitate cooperation by encoding a perceptible signal, the ability to detect it, and a tendency to help others that display it. Falsebeards are hypothetical cheaters that display the signal without being altruistic. Despite many examples of greenbeards, evidence for falsebeards is scarce. The Dictyostelium discoideum tgrB1-tgrC1 allorecognition pathway encodes a greenbeard. It allows development, which yields fruiting bodies with altruistic stalks that increase spore dispersal. Here we show that cells lacking rapgapB, a tgrB1-tgrC1 signaling element, cheat by avoiding the stalk fate and generating more spores in chimeras than in pure populations. rapgapB– cells cheat only on …

Pkc-Mediated Phosphorylation Governs The Stability And Function Of Celf1 As A Driver Of Emt In Breast Epithelial Cells, Shebna Massey, Natee Kongchan, Yang Gao, Arindam Chaudhury, Emuejevoke Olokpa, Jason Karch, Anna Malovannaya, Chonghui Cheng, Xiang Zhang, Joel R Neilson

Faculty, Staff and Students Publications

Epithelial to mesenchymal transition (EMT) is believed to be a principal factor contributing to cancer metastasis. The post-transcriptional and post-translational mechanisms underlying EMT are comparatively underexplored. We previously demonstrated that the CELF1 RNA binding protein is necessary and sufficient to drive the EMT of breast epithelial cells, and that the relative protein expression of CELF1 in this context was dictated at the post-translational level. Here, we elucidate the mechanism of this regulation. Mass spectrometric analysis of CELF1 isolated from mesenchymal MCF-10A cells identified multiple sites of serine and threonine phosphorylation on the protein, correlating with the increased stability of this …

The Divergent Responses Of Salinity Generalists To Hyposaline Stress Provide Insights Into The Colonisation Of Freshwaters By Diatoms, Kathryn J. Judy, Eveline Pinseel, Kala M. Downey, Jeffrey A. Lewis, Andrew J. Alverson

Biological Sciences Faculty Publications and Presentations

Environmental transitions, such as the salinity divide separating marine and fresh waters, shape biodiversity over both shallow and deep timescales, opening up new niches and creating opportunities for accelerated speciation and adaptive radiation. Understanding the genetics of environmental adaptation is central to understanding how organisms colonise and subsequently diversify in new habitats. We used time-resolved transcriptomics to contrast the hyposalinity stress responses of two diatoms. Skeletonema marinoi has deep marine ancestry but has recently invaded brackish waters. Cyclotella cryptica has deep freshwater ancestry and can withstand a much broader salinity range. Skeletonema marinoi is less adept at mitigating even mild …

Rictor, A Mtorc2 Protein, Regulates Lymphatic Valve Formation And Maintenance Through The Akt-Foxo1 Signaling Axis, Richa Banerjee

USF Tampa Graduate Theses and Dissertations

The lymphatic vasculature maintains tissue fluid homeostasis by absorbing interstitial fluid to form lymph and transporting it back to the bloodstream. Collecting lymphatic vessels have lymphatic valves (LVs) that prevent the retrograde flow of lymph generated by hydrostatic pressure from the blood vasculature. Backflow and accumulation of lymph leads to a lymphatic pathology called lymphedema. This implicates the involvement of defective LVs in the pathogenesis of lymphedema and warrants the study of lymphatic valve development and maintenance. The LVs are formed through a process called mechanotransduction which signals through the intracellular PI3K-AKT pathway in lymphatic endothelial cells. However, the activation …

Porous Iron Electrodes Reduce Energy Consumption During Electrocoagulation Of A Virus Surrogate: Insights Into Performance Enhancements Using Three-Dimensional Neutron Computed Tomography, Kyungho Kim, Cesar Castillo, Gyoung G Jang, Yuxuan Zhang, Costas Tsouris, Shankararaman Chellam

Faculty, Staff and Students Publications

Electrocoagulation has attracted significant attention as an alternative to conventional chemical coagulation because it is capable of removing a wide range of contaminants and has several potential advantages. In contrast to most electrocoagulation research that has been performed with nonporous electrodes, in this study, we demonstrate energy-efficient iron electrocoagulation using porous electrodes. In batch operation, investigation of the external pore structures through optical microscopy suggested that a low porosity electrode with sparse connection between pores may lead to mechanical failure of the pore network during electrolysis, whereas a high porosity electrode is vulnerable to pore clogging. Electrodes with intermediate porosity, …

Identification Of An Ionic Mechanism For Erα-Mediated Rapid Excitation In Neurons, Meng Yu, Na Yin, Bing Feng, Peiyu Gao, Kaifan Yu, Hesong Liu, Hailan Liu, Yongxiang Li, Olivia Z Ginnard, Kristine M Conde, Mengjie Wang, Xing Fang, Longlong Tu, Jonathan C Bean, Qingzhuo Liu, Yue Deng, Yuxue Yang, Junying Han, Sanika V Jossy, Megan L Burt, Huey Zhong Wong, Yongjie Yang, Benjamin R Arenkiel, Yang He, Shaodong Guo, Pierre Gourdy, Jean-Francois Arnal, Francoise Lenfant, Zhao Wang, Chunmei Wang, Yanlin He, Yong Xu

Faculty, Staff and Students Publications

The major female ovarian hormone, 17β-estradiol (E2), can alter neuronal excitability within milliseconds to regulate a variety of physiological processes. Estrogen receptor-α (ERα), classically known as a nuclear receptor, exists as a membrane-bound receptor to mediate this rapid action of E2, but the ionic mechanisms remain unclear. Here, we show that a membrane channel protein, chloride intracellular channel protein-1 (Clic1), can physically interact with ERα with a preference to the membrane-bound ERα. Clic1-mediated currents can be enhanced by E2 and reduced by its depletion. In addition, Clic1 currents are required to mediate the E2-induced rapid excitations in multiple brain ERα …

Water Quality Of Silver Creek, A Buried Urban Stream, Nick Bultje, Valerie Krause, Rebecca Nulty

Student Papers and Reports

There are many sources of pollution that can affect a watershed. These pollutants can impact the water's pH, temperature, conductivity, and dissolved solids. Escherichia coli is a specific pollutant that comes from waste products of humans and animals. High levels of E. coli cause serious health problems. This study examines Silver Creek, a tributary within the Plaster Creek watershed. Silver Creek runs mostly underground and has storm drainage systems that flow into the creek. The goal was to explore the effects of the underground section of Silver Creek on water quality and E. coli levels. The water quality and levels …

Oxidative Stress Responses In Arabidopsis Thaliana Plants To Uv-B Irradiation, Bolaji Olalere

Theses

The depletion of the stratospheric ozone layer has led to increased levels of harmful UV-B radiation reaching the Earth's surface, posing significant challenges for plant health and development. This study investigates the oxidative stress responses in Arabidopsis thaliana when exposed to UV-B irradiation. Arabidopsis thaliana, a well-established model organism, is particularly sensitive to UV-B, making it ideal for understanding the effects of UV-B-induced oxidative stress. UV-B radiation, a mutagenic component of sunlight, disrupts key metabolic, molecular, and developmental processes, leading to DNA damage, impaired metabolism, and morphological changes. This research aims to explore how UV-B exposure affects the activities of …

A Method For Rapid And Reliable Quantification Of Vegf-Cell Binding Activity, Prabuddha Waduge, Avinash Kaur, Wei Li

Faculty, Staff and Students Publications

Vascular endothelial growth factor (VEGF) is a pleiotropic growth factor that binds a broad spectrum of cell types and regulates diverse cellular processes, including angiogenesis, growth and survival. However, it is technically difficult to quantify VEGF-cell binding activity because of reversible nature of ligand-receptor interactions. Here we used T7 bacteriophage display to quantify and compare binding activity of three human VEGF-A (hVEGF) isoforms, including hVEGF111, 165 and 206. All three isoforms bound equally well to immobilized aflibercept, a decoy VEGF receptor. hVEGF111-Phage exhibited minimal binding to immobilized heparan sulfate, whereas hVEGF206-Phage and hVEGF165-Phage had the highest and intermediate binding to …

Multivalent Protein-Nucleic Acid Interactions Probed By Composition-Gradient Multiangle Light Scattering, Josephine C Ferreon, Natee Kongchan, Phoebe S Tsoi, Kyoung-Jae Choi, Sophia Kenrick, Joel Neilson, Allan Chris M Ferreon

Faculty, Staff and Students Publications

Many RNA-binding proteins, such as TDP-43 or CELF1, interact multivalently with nucleic acid repetitive elements. The molecular stoichiometry of protein to nucleic acid is often difficult to assess, particularly by standard electrophoretic mobility shift assays (EMSAs). Here, we investigate the use of composition-gradient multiangle light scattering (CG-MALS) for quantifying binding affinity and stoichiometry for two RNA-binding proteins with their nucleic acid partners of varied sequence and length: TDP43's N-terminal RNA recognition motifs with both TG/GU-repeat ssDNA and ssRNA, respectively, and CELF1's two N-terminal RNA recognition motifs with (TG/UGUU/GU) repeats and an experimentally defined cognate GU-rich element (GRE). Our CG-MALS data …

Integrated Safety And Efficacy Analyses Of Phase 3 Trials Of A Microbiome Therapeutic For Recurrent Cdi, Colleen S Kraft, Matthew Sims, Michael Silverman, Thomas J Louie, Paul Feuerstadt, Edward S Huang, Sahil Khanna, Charles S Berenson, Elaine E L Wang, Stuart H Cohen, Louis Korman, Christine Lee, Colleen R Kelly, Alberto Odio, Paul P Cook, Bret Lashner, Mayur Ramesh, Princy Kumar, Ananya De, Asli Memisoglu, David A Lombardi, Brooke R Hasson, Barbara H Mcgovern, Lisa Von Moltke, Darrell S Pardi, Ecospor Iii And Ecospor Iv Investigators

Faculty, Staff and Students Publications

INTRODUCTION: Recurrent Clostridioides difficile infection (rCDI) often occurs after standard-of-care antibiotics. VOWST oral spores (VOS, previously SER-109), an FDA-approved orally administered microbiome therapeutic, is indicated to prevent rCDI following antibiotics for rCDI.

OBJECTIVE, DESIGN, AND PATIENTS: To evaluate safety and efficacy of VOS from two phase 3 trials, (randomized, placebo-controlled [ECOSPOR III: NCT03183128] and open-label, single arm [ECOSPOR IV: NCT03183141]) of 349 adults with rCDI and prevalent comorbidities.

METHODS: VOS or placebo [ECOSPOR III only] (4 capsules once daily for 3 days). Integrated analysis of treatment-emergent adverse events (TEAEs) collected through week 8; serious TEAEs and TEAEs of special interest …

Metabolic Crossroads: Gaba Synthesis In Trichomonas Vaginalis Infection, Yesha Dhruv

Biochemistry and Molecular Biology

This study examines the gamma-aminobutyric acid (GABA) synthesis pathway in Trichomonas vaginalis infection of human HCT-8 cells, focusing on key enzymatic processes in glutamate conversion to GABA and metabolic adaptations. The hypothesis tested was that T. vaginalis modulates GABA metabolism to enhance host cell invasion and adaptation. Infection time-point studies, RNA sequencing, and aldehyde dehydrogenase (ALDH) assays were conducted. Comparisons between T. vaginalis strains Casu 2 and Casu 2/MOZ 2 revealed distinct infection dynamics. Casu 2 rapidly attached and replicated within an hour, peaking at 24 hours, while Casu 2/MOZ 2 exhibited delayed replication, peaking at 48 to 72 hours, …

Proteomic Analysis Reveals Major Proteins And Pathways That Mediate The Effect Of 17-Β-Estradiol In Cell Division And Apoptosis In Breast Cancer Mcf7 Cells, Zhenqi Zhou, Brihget Sicairos, Jianhong Zhou, Yuchun Du

Biological Sciences Faculty Publications and Presentations

Despite extensive research, the genes/proteins and pathways responsible for the physiological effects of estrogen remain elusive. In this study, we determined the effect of estrogen on global protein expression in breast cancer MCF7 cells using a proteomic method. The expression of 77 cytosolic, 74 nuclear, and 81 membrane/organelle proteins was significantly altered by 17-β-estradiol (E2). Protein enrichment analyses suggest that E2 may stimulate cell division primarily by promoting the G1 to S phase transition and advancing the G2/M checkpoint. The effect of E2 on cell survival was complex, as it could simultaneously enhance and inhibit apoptosis. Bioinformatics analysis suggests that …

Vglut2-Based Glutamatergic Signaling In Central Noradrenergic Neurons Is Dispensable For Normal Breathing And Chemosensory Reflexes, Yuan Chang, Savannah Lusk, Andersen Chang, Christopher S Ward, Russell S Ray

Faculty, Staff and Students Publications

Central noradrenergic (NA) neurons are key constituents of the respiratory homeostatic network. NA dysfunction is implicated in several developmental respiratory disorders including Congenital Central Hyperventilation Syndrome (CCHS), Sudden Infant Death Syndrome (SIDS), and Rett Syndrome. The current unchallenged paradigm in the field, supported by multiple studies, is that glutamate co-transmission in subsets of central NA neurons plays a role in breathing control. If true, NA-glutamate co-transmission may also be mechanistically important in respiratory disorders. However, the requirement of NA-derived glutamate in breathing has not been directly tested and the extent of glutamate co-transmission in the central NA system remains uncharacterized. …

Myc Induces Oncogenic Stress Through Rna Decay And Ribonucleotide Catabolism In Breast Cancer, Jitendra K Meena, Jarey H Wang, Nicholas J Neill, Dianne Keough, Nagireddy Putluri, Panagiotis Katsonis, Amanda M Koire, Hyemin Lee, Elizabeth A Bowling, Siddhartha Tyagi, Mayra Orellana, Rocio Dominguez-Vidaña, Heyuan Li, Kenneth Eagle, Charles Danan, Hsiang-Ching Chung, Andrew D Yang, William Wu, Sarah J Kurley, Brian M Ho, Joseph R Zoeller, Calla M Olson, Kristen L Meerbrey, Olivier Lichtarge, Arun Sreekumar, Clifford C Dacso, Luke W Guddat, Dominik Rejman, Dana Hocková, Zlatko Janeba, Lukas M Simon, Charles Y Lin, Monica C Pillon, Thomas F Westbrook

Faculty, Staff and Students Publications

Upregulation of MYC is a hallmark of cancer, wherein MYC drives oncogenic gene expression and elevates total RNA synthesis across cancer cell transcriptomes. Although this transcriptional anabolism fuels cancer growth and survival, the consequences and metabolic stresses induced by excess cellular RNA are poorly understood. Herein, we discover that RNA degradation and downstream ribonucleotide catabolism is a novel mechanism of MYC-induced cancer cell death. Combining genetics and metabolomics, we find that MYC increases RNA decay through the cytoplasmic exosome, resulting in the accumulation of cytotoxic RNA catabolites and reactive oxygen species. Notably, tumor-derived exosome mutations abrogate MYC-induced cell death, suggesting …

Death-Associated Protein Kinase 3 Modulates Migration And Invasion Of Triple-Negative Breast Cancer Cells, Junkai Wang, Anh M Tran-Huynh, Beom-Jun Kim, Doug W Chan, Matthew V Holt, Diana Fandino, Xin Yu, Xiaoli Qi, Jin Wang, Weijie Zhang, Yi-Hsuan Wu, Meenakshi Anurag, Xiang H F Zhang, Bing Zhang, Chonghui Cheng, Charles E Foulds, Matthew J Ellis

Faculty, Staff and Students Publications

Sixteen patient-derived xenografts (PDXs) were analyzed using a mass spectrometry (MS)-based kinase inhibitor pull-down assay (KIPA), leading to the observation that death-associated protein kinase 3 (DAPK3) is significantly and specifically overexpressed in the triple-negative breast cancer (TNBC) models. Validation studies confirmed enrichment of DAPK3 protein, in both TNBC cell lines and tumors, independent of mRNA levels. Genomic knockout of DAPK3 in TNBC cell lines inhibited in vitro migration and invasion, along with down-regulation of an epithelial–mesenchymal transition (EMT) signature, which was confirmed in vivo. The kinase and leucine-zipper domains within DAPK3 were shown by a mutational analysis to be essential …