Biochemistry, Biophysics, and Structural Biology Commons^™

Eukaryotic Initiation Factor 3 Interactions With Structural Elements Of Barley Yellow Dwarf Virus Untranslated Regions Reveal Details Of A New Cap-Independent Translation Initiation Model, Paul S. Powell

Dissertations, Theses, and Capstone Projects

Barley Yellow Dwarf Virus (BYDV) is a positive strand RNA plant virus that translates without using a 5′ 7-methylguanosine cap or a 3′ poly-adenosine tail, features that are required for canonical mRNA translation. BYDV’s non-canonical translation relies on RNA structures in the 5′ and 3′ untranslated regions (UTRs) to recruit eukaryotic initiation factors (eIFs) and ribosomes. BYDV’s 3′ translation enhancer (BTE) is a cruciform structure capable of recruiting the cap-binding complex eIF4F, the large scaffolding complex eIF3, and the 40S ribosomal subunit. Together eIF3, eIF4F, and BTE influence factor binding and 40S recruitment on the 5′ UTR and play a …

An In Silico Approach To Investigate The Structural And Biochemical Basis Of The Rna Binding Functions Of Nucleolin, Avdar San

Dissertations, Theses, and Capstone Projects

Nucleolin (NCL) is a stress responsive multifunctional nucleolar protein and accounts for 10% of the total nucleolar protein content. NCL belongs to the class of RNA binding proteins (RBPs) that regulate many important cellular processes through their interactions with different RNA molecules. The dysregulation of RBPs and the RNA metabolism pathways they intersect is a known driver of tumorigenesis. NCL regulates ribosome biogenesis, chromatin remodeling, microRNA processing, and gene expression on multiple levels. The RNA-protein interactions of NCL are primarily driven by its four RNA binding domains (RBDs). NCL is known to interact with a growing list of primary-miRNA (pri-miRNA) …

Role Of Metals In Human Immune System: Study Of Metal-Dependent Structural Changes Of S100a12 Protein, Aleksey Aleshintsev

Dissertations, Theses, and Capstone Projects

S100A12 protein belongs to the S100 family of calcium-binding proteins and participates in the innate immune system. Antimicrobial proteins from the S100 family of the proteins (S100A12, S100A8/A9, etc.) are secreted and expressed by neutrophils during microbial infection and perform their antimicrobial activity through metal sequestration. While most S100 proteins function intracellularly, S100A12 is highly expressed and secreted into the extracellular space by neutrophils during infection. Sequestration of Zn²⁺ by S100A12 is aided by the nanomolar zinc binding affinity of the protein at neutral pH conditions, which is further enhanced upon calcium-binding. The Zn²⁺ binding scaffold in S100A12 …

Structural And Biochemical Investigations Of The Initiation Of Dna Replication In Bacteriophage Lambda And Escherichia Coli, Jillian D. Chase

Dissertations, Theses, and Capstone Projects

Faithful transmission of genetic information is requisite for the propagation of all life. DNA replication in each of the three domains of life requires the separation of double stranded DNA (dsDNA) into single stranded DNA (ssDNA) which then serves as a template for genomic duplication of each original DNA strand. Initiation of replication events occurs by tightly regulated processes during which specialized proteins are loaded at a specific locus within the genome, termed the origin of replication, in preparation of bidirectional replication events. A replicative helicase must be loaded or assembled on both strands of DNA at the origin to …

Paddling Along The Voltage Gated Sodium Channel Galaxy With Sea Anemone Toxins: Structural Studies Of The Interaction Between The Paddle Motif From Nav1.5div And Sea Anemone Toxin, Adel K. Hussein

Dissertations, Theses, and Capstone Projects

Voltage gated sodium channels (VGSC) are membrane proteins that serve an important function in the central nervous system (CNS), peripheral nervous system (PNS), and cardiac muscles amongst others. The main function of VGSC is in the propagation of electrical signals by depolarizing excitable cells. Nine mammalian VGSC subtypes have been characterized, Na_V1.1 – Na_V1.9, that are expressed in a tissue specific manner, each with unique gating properties. Numerous diseases have been linked to defects in VGSC including epilepsy, mental retardation, long QT syndrome, and Brugada disease. Furthermore, these channels are one of the primary targets of …

Scientific Development Of An Integrated Workflow For Latent Print, Questioned Document, And Dna Processing Of Paper Evidence, Ashley Morgan

Dissertations, Theses, and Capstone Projects

Touch paper evidence could be the source of probative human DNA but recovery is challenging and forensic laboratories instead prioritize processing by the Latent Print and Questioned Document disciplines. Recent advances in DNA collection methods and the increased sensitivity of STR typing kits have improved success rates for DNA testing of paper evidence; but prior to implementing DNA collection, laboratories have to decide in which order to examine paper for the different types of forensic evidence. This thesis developed and tested a multi-discipline workflow for processing paper evidence by DNA, Latent Prints and Questioned Documents experts. Preliminary sampling studies indicated …

Water-Based Lead Generation, Brian Olson

Dissertations, Theses, and Capstone Projects

Water-based Lead Generation. The opioid epidemic and the SARS-CoV-2 pandemic are current serious challenges whose devastating effects could be assuaged through the development of new drugs. Opioids that are functional painkillers, that are less likely to cause overdose, and small molecule drugs that could inhibit the life cycle of SARS-CoV-2 would be useful. The work herein investigated the use of water molecules for lead generation in drug development against opioid receptors and SARS-CoV-2 viral proteins. In opioid receptor binding sites, purported bridging waters were obtained from crystal waters or from molecular dynamics simulations, as Hydration Site Analysis was used to …

In Vitro Toxicological Evaluation Of Mesoporous Silica Microparticles Functionalised 1 With Carvacrol And Thymol, Cristina Fuentes, Ana Fuentes, Hugh Byrne, José Barat, María José Ruiz

Articles

The cytotoxicity of carvacrol- and thymol- functionalised mesoporous silica microparticles (MCM-41) was assessed in the human hepatocarcinoma cell line (HepG2). Cell viability, lactate dehydrogenase (LDH) activity, reactive oxygen species (ROS) production, mitochondrial membrane potential (ΔΨm), lipid peroxidation (LPO) and apoptosis/necrosis analysis were used as endpoints. Results showed that both materials induced cytotoxicity in a time and concentration-dependent manner, being more cytotoxic than free essential oil components and bare MCM-41. This effect was caused by the cell-particle interactions and not from degradation products released to the culture media, as demonstrated in the extract dilution assays. LDH release was seen to be …

Two Heads Are Better Than One: Current Landscape Of Integrating Qsp And Machine Learning, Tongli Zhang, Ioannis P. Androulakis, Peter Bonate, Limei Cheng, Tomáš Helikar, Jaimit Parikh, Christopher Rackauckas, Kalyanasundaram Subramanian, Carolyn R. Cho

Department of Biochemistry: Faculty Publications

Quantitative systems pharmacology (QSP) modeling is applied to address essential questions in drug development, such as the mechanism of action of a therapeutic agent and the progression of disease. Meanwhile, machine learning (ML) approaches also contribute to answering these questions via the analysis of multi-layer ‘omics’ data such as gene expression, proteomics, metabolomics, and high-throughput imaging. Furthermore, ML approaches can also be applied to aspects of QSP modeling. Both approaches are powerful tools and there is considerable interest in integrating QSP modeling and ML. So far, a few successful implementations have been carried out from which we have learned about …

Histone Post-Translational Modification Dysregulation Contributes To Toxicity In Amyotrophic Lateral Sclerosis Proteinopathy Models, Seth A. Bennett

Dissertations, Theses, and Capstone Projects

Amyotrophic Lateral Sclerosis (ALS) is the third most common adult onset neurodegenerative disorder worldwide. It is generally characterized by progressive paralysis starting at the limbs ultimately leading to death caused by respiratory failure. There is no cure and current treatments fail to slow the progression of the disease. As such, new treatment options are desperately needed. Epigenetic targets are an attractive possibility because they are reversible. Epigenetics refers to heritable changes in gene expression unrelated to changes in DNA sequence. Histone modifications, a main epigenetic mechanism, occur in many amino acid residues and include phosphorylation, acetylation, methylation as well as …

Extracellular Secretion Of A Cutinase With Polyester-Degrading Potential By E. Coli Using A Novel Signal Peptide From Amycolatopsis Mediterranei, Yeqi Tan, Gemma K. Kinsella, Gary T. Henehan, Barry J. Ryan

Articles

Recent studies in this laboratory showed that an extracellular cutinase from A. mediterranei (AmCut) was able to degrade the plastics polycaprolactone and polybutylene succinate. Such plastics can be slow to degrade in soils due to a lack of efficient polyester degrading organisms. AmCut also showed potential for the biocatalytic synthesis of esters by reverse hydrolysis.

The gene for AmCut has an upstream leader sequence whose transcript is not present in the purified enzyme. In this study, we show using predictive modelling, that this sequence codes for an N-terminal signal peptide that directs transmembrane expression via the Sec secretion pathway.

E. …

Detecting Anomalies In Retinal Diseases Using Generative, Discriminative, And Self-Supervised Deep Learning, Philippe Burlina, William Paul, T Y Alvin Liu, Neil M Bressler

Faculty, Staff and Students Publications

IMPORTANCE: Anomaly detectors could be pursued for retinal diagnoses based on artificial intelligence systems that may not have access to training examples for all retinal diseases in all phenotypic presentations. Possible applications could include screening of population for any retinal disease rather than a specific disease such as diabetic retinopathy, detection of novel retinal diseases or novel presentations of common retinal diseases, and detection of rare diseases with little or no data available for training.

OBJECTIVE: To study the application of anomaly detection to retinal diseases.

DESIGN, SETTING, AND PARTICIPANTS: High-resolution retinal images from the publicly available EyePACS data set …

Race/Ethnicity And Birthplace As Risk Factors For Gastric Intestinal Metaplasia In A Multiethnic United States Population, Mimi C Tan, Taher Jamali, Theresa H Nguyen, Amy Galvan, Robert J Sealock, Anam Khan, Neda Zarrin-Khameh, Ashley Holloman, Ourania Kampagianni, David Henriquez Ticas, Yan Liu, Hashem B El-Serag, Aaron P Thrift

Faculty, Staff and Students Publications

INTRODUCTION: Several US subgroups have increased risk of gastric cancer and gastric intestinal metaplasia (GIM) and may benefit from targeted screening. We evaluated demographic and clinical risk factors for GIM and examined the interaction between race/ethnicity and birthplace on GIM risk.

METHODS: We identified patients who had undergone esophagogastroduodenoscopy with gastric biopsy from 3/2006-11/2016 using the pathology database at a safety net hospital in Houston, Texas. Cases had GIM on ≥1 gastric biopsy histopathology, whereas controls lacked GIM on any biopsy. We estimated odds ratios and 95% confidence intervals (CI) for associations with GIM risk using logistic regression and developed …

Maximum Dose Food Challenges Reveal Transient Sustained Unresponsiveness In Peanut Oral Immunotherapy (Poimd Study), Carla M Davis, Aikaterini Anagnostou, Sridevi Devaraj, Daisy T Vita, Fabian Rivera, Kathleen Pitts, Melissa Hearrell, Charles Minard, Danielle Guffey, Meera Gupta, Levi Watkin, Jordan S Orange, Sara Anvari

Faculty, Staff and Students Publications

BACKGROUND: The maximum tolerated dose of peanut protein following peanut oral immunotherapy (POIT) is unknown because most research studies have not examined very high thresholds.

OBJECTIVE: To define the maximum dose tolerated by patients on POIT and severity of allergic reactions after a 1-month period of treatment discontinuation.

METHODS: In a phase 2 3-year POIT open-label study, we enrolled participants age 5 to 13 years with a 1-year build-up period followed by a 2-year daily maintenance dose of 3900 mg with assessment of the maximum tolerated dose using double-blind placebo-controlled food challenges (DBPCFCs) of 26,225 mg cumulative dose of peanut …

Comparative Performance Of Risk Prediction Models For Hepatitis B-Related Hepatocellular Carcinoma In The United States, Hyun-Seok Kim, Xian Yu, Jennifer Kramer, Aaron P Thrift, Pete Richardson, Yao-Chun Hsu, Avegail Flores, Hashem B El-Serag, Fasiha Kanwal

Faculty, Staff and Students Publications

BACKGROUND & AIMS: Guidelines recommend hepatocellular carcinoma (HCC) surveillance in patients with chronic HBV infection. Several HCC risk prediction models are available to guide surveillance decisions, but their comparative performance remains unclear.

METHODS: Using a retrospective cohort of patients with HBV treated with nucleos(t)ide analogues at 130 Veterans Administration facilities between 9/1/2008 and 12/31/2018, we calculated risk scores from 10 HCC risk prediction models (REACH-B, PAGE-B, m-PAGE-B, CU-HCC, HCC-RESCUE, CAMD, APA-B, REAL-B, AASL-HCC, RWS-HCC). We estimated the models' discrimination and calibration. We calculated HCC incidence in risk categories defined by the reported cut-offs for all models.

RESULTS: Of 3,101 patients …

Randomized Phase Iii Bmt Ctn Trial Of Calcineurin Inhibitor-Free Chronic Graft-Versus-Host Disease Interventions In Myeloablative Hematopoietic Cell Transplantation For Hematologic Malignancies, Leo Luznik, Marcelo C Pasquini, Brent Logan, Robert J Soiffer, Juan Wu, Steven M Devine, Nancy Geller, Sergio Giralt, Helen E Heslop, Mary M Horowitz, Richard J Jones, Mark R Litzow, Adam Mendizabal, Lori Muffly, Eneida R Nemecek, Lynn O'Donnell, Richard J O'Reilly, Raquel Palencia, Johannes Schetelig, Leyla Shune, Scott R Solomon, Sumithira Vasu, Vincent T Ho, Miguel-Angel Perales

Faculty, Staff and Students Publications

PURPOSE: Calcineurin inhibitors (CNI) are standard components of graft-versus-host disease (GVHD) prophylaxis after hematopoietic cell transplantation (HCT). Prior data suggested that CNI-free approaches using donor T-cell depletion, either by ex vivo CD34 selection or in vivo post-transplant cyclophosphamide (PTCy) as a single agent, are associated with lower rates of chronic GVHD (cGVHD).

METHODS: This multicenter phase III trial randomly assigned patients with acute leukemia or myelodysplasia and an HLA-matched donor to receive CD34-selected peripheral blood stem cell, PTCy after a bone marrow (BM) graft, or tacrolimus and methotrexate after BM graft (control). The primary end point was cGVHD (moderate or …

Extensive Identification Of Genes Involved In Congenital And Structural Heart Disorders And Cardiomyopathy, Nadine Spielmann, Gregor Miller, Tudor I Oprea, Chih-Wei Hsu, Gisela Fobo, Goar Frishman, Corinna Montrone, Hamed Haseli Mashhadi, Jeremy Mason, Violeta Munoz Fuentes, Stefanie Leuchtenberger, Andreas Ruepp, Matias Wagner, Dominik S Westphal, Cordula Wolf, Agnes Görlach, Adrián Sanz-Moreno, Yi-Li Cho, Raffaele Teperino, Stefan Brandmaier, Sapna Sharma, Isabella Rikarda Galter, Manuela A Östereicher, Lilly Zapf, Philipp Mayer-Kuckuk, Jan Rozman, Lydia Teboul, Rosie K A Bunton-Stasyshyn, Heather Cater, Michelle Stewart, Skevoulla Christou, Henrik Westerberg, Amelia M Willett, Janine M Wotton, Willson B Roper, Audrey E Christiansen, Christopher S Ward, Jason D Heaney, Corey L Reynolds, Jan Prochazka, Lynette Bower, David Clary, Mohammed Selloum, Ghina Bou About, Olivia Wendling, Hugues Jacobs, Sophie Leblanc, Hamid Meziane, Tania Sorg, Enrique Audain, Arthur Gilly, Nigel W Rayner, Impc Consortium, Genomics England Research Consortium;, Marc-Phillip Hitz, Eleftheria Zeggini, Eckhard Wolf, Radislav Sedlacek, Steven A Murray, Karen L Svenson, Robert E Braun, Jaqueline K White, Lois Kelsey, Xiang Gao, Toshihiko Shiroishi, Ying Xu, Je Kyung Seong, Fabio Mammano, Glauco P Tocchini-Valentini, Arthur L Beaudet, Terrence F Meehan, Helen Parkinson, Damian Smedley, Ann-Marie Mallon, Sara E Wells, Harald Grallert, Wolfgang Wurst, Susan Marschall, Helmut Fuchs, Steve D M Brown, Ann M Flenniken, Lauryl M J Nutter, Colin Mckerlie, Yann Herault, K C Kent Lloyd, Mary E Dickinson, Valerie Gailus-Durner, Martin Hrabe De Angelis

Faculty, Staff and Students Publications

Clinical presentation of congenital heart disease is heterogeneous, making identification of the disease-causing genes and their genetic pathways and mechanisms of action challenging. By using in vivo electrocardiography, transthoracic echocardiography and microcomputed tomography imaging to screen 3,894 single-gene-null mouse lines for structural and functional cardiac abnormalities, here we identify 705 lines with cardiac arrhythmia, myocardial hypertrophy and/or ventricular dilation. Among these 705 genes, 486 have not been previously associated with cardiac dysfunction in humans, and some of them represent variants of unknown relevance (VUR). Mice with mutations in Casz1, Dnajc18, Pde4dip, Rnf38 or Tmem161b genes show developmental cardiac structural abnormalities, …

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 …

Repurposing Metformin And Antifolates For The Treatment Of Hepatocellular Carcinoma, Sherouk Mohamed Tawfik

Theses and Dissertations

Hepatocellular carcinoma (HCC), one of the most prevalent types of cancers worldwide, continues to maintain high levels of resistance to standard therapy. As clinical data revealed poor response rates, the need for developing new methods has increased to improve the overall wellbeing of patients with HCC. Due to its safety, wide availability and previously reported anti-cancer effects, metformin (MET) serves to be a possible therapeutic agent when combined with other well-known anti-cancer agents. The aim of this study was to investigate the potential anti-cancer effects of MET, an anti-diabetic agent, when combined with two antifolate drugs: trimethoprim (TMP) or methotrexate …

Conformational Flexibility And Local Frustration In The Functional States Of The Sars-Cov-2 Spike B.1.1.7 And B.1.351 Variants: Mutation-Induced Allosteric Modulation Mechanism Of Functional Dynamics And Protein Stability, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Structural and functional studies of the SARS-CoV-2 spike proteins have recently determined distinct functional states of the B.1.1.7 and B.1.351 spike variants, providing a molecular framework for understanding the mechanisms that link the effect of mutations with the enhanced virus infectivity and transmissibility. A detailed dynamic and energetic analysis of these variants was undertaken in the present work to quantify the effects of different mutations on functional conformational changes and stability of the SARS-CoV-2 spike protein. We employed the efficient and accurate coarse-grained (CG) simulations of multiple functional states of the D614G mutant, B.1.1.7 and B.1.351 spike variants to characterize …