Medical Biochemistry Commons^™

Exploration Of A Relationship Between The Activities Of Trail And 4’-Trifluoromethoxychalcone., Abigail C. Ernst

Undergraduate Theses

Cancer is the overgrowth of dysregulated or mutated cells that affects 1 in 3 Americans. Chalcones are natural products with many possible derivatives, such as 4’-trifluromethoxychalcone (4TF), developed in Dr. Krzysiak’s lab, which exhibit anticancer activity against cancer cell lines. Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a tumor surveillance cytokine that acts on two receptor types: death receptors and decoy receptors. One way cancer cells can become resistant to TRAIL is by upregulating decoy receptors and/or downregulating death receptors. In this study, MTS assays evaluated the potential relationship between TRAIL and 4TF that sensitizes A549 cells to TRAIL. The …

Biocomputing Approach To Modeling And Modulating Calcium Signaling, Sehee Sun

School of Computing: Dissertations, Theses, and Student Research

Biocomputing is an emerging field that seeks to perform computational tasks using biological substrates and processes. Unlike conventional computing systems based on silicon hardware, biocomputing leverages the parallelism, energy efficiency, and complex dynamics of living systems. Among various cellular mechanisms, calcium (Ca2+) signaling stands out as a central regulator of diverse biological functions, offering a promising basis for programmable logic and control in living cells.

This thesis introduces a novel framework for modeling and modulating Ca2+ dynamics using biologically inspired Boolean logic circuits. Specifically, we propose the Ca2+ Boolean Logic (CaBL) model, in which Ca2+ fluxes and interactions are abstracted …

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 …

Ion-Dna Interactions As A Key Determinant Of Uracil Dna Glycosylase Activity., Sharon N Greenwood, Alexis N Dispensa, Matthew Wang, Justin R Bauer, Timothy D Vaden, Zhiwei Liu, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Because of their ubiquitous presence, ions interact with numerous macromolecules in the cell and affect critical biological processes. Here, we discuss how cations including Mg²⁺ alter the enzymatic activity of a DNA glycosylase by tuning its affinity for DNA. The response of uracil DNA glycosylase (UNG2) to Mg²⁺ ions in solution is biphasic and paradoxical, where low concentrations of the ion stimulate the enzyme, but high concentrations inhibit the enzyme. We analyzed this phenomenon by modeling experimental data with a statistical framework that we empirically derived to understand molecular systems that display biphasic behaviors. Parameters from our statistical …

Exploring Intracellular Signaling Responses To Ks18, A Potent Mcl-1 Inhibitor, In Multiple Myeloma, Emily Nelson, Omar S Al-Odat, Dhruti A. Brahmbhatt, Tulin Budak-Alpdogan, Subash Jonnalagadda, Manoj Kumar Pandey

Rowan-Virtua Research Day

Multiple myeloma (MM), a cancer of plasma B cells, is a hematological malignancy in which patients inevitably relapse and develop drug resistance. Mcl-1, a member of the anti-apoptotic subgroup of Bcl-2 family proteins, plays a critical role in the progression of multiple myeloma and contributes significantly to drug resistance. Elevated Mcl-1 expression is observed in approximately 52% of MM patients at diagnosis, increasing to 81% at relapse. Given its driving role in disease progression and therapy resistance, Mcl-1 inhibition has emerged as a promising therapeutic target, prompting ongoing research into the development and clinical evaluation of Mcl-1 inhibitors, particularly for …

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 …

In-Silico Modeling And Characterization Of Kcc2 Protein Interaction With A Small Molecule Direct Agonist Identifies Potential Binding Sites For Modulating Behaviors Associated With Substances Of Abuse, William Hai Dang Ho, Alfred Amendolara, Kenyon Mitchell, Jaden Miner, Ruth Northcott, Braxton Bingham, Andrew J. Payne

Annual Research Symposium

Purpose

KCC2 is a potassium-chloride cotransporter that plays a critical role in neuronal function by regulating GABAergic signaling via chloride gradients. Maintaining this concentration gradient is crucial for balancing excitation and inhibition in the brain. While KCC2 dysregulation has been implicated in epilepsy and seizures, recent studies suggest that KCC2 inhibition results in phenotypes mirroring those seen in chronic opioid dependence. As such, increasing evidence support KCC2 being a potential therapeutic target for modulating behaviors associated with substances of abuse. Currently, only a few direct small molecule agonists against KCC2 have been reported, and no definitive active site on the …

Targeting The Cholesterol Storage Enzyme Acat1/Soat1 In Brain Cells And Mouse Model: A Novel Approach To Address Aging And Apoe4-Related Neuroinflammation, Thao Nguyen Phuong Huynh Krumeich

Dartmouth College Ph.D Dissertations

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease that significantly impacts nearly 7 million people in the United States. AD is characterized by the deposition of amyloid beta (Ab) plaque, tau neurofibrillary tangles (NFTs), lipids granules, and neuroinflammation. Age and apolipoprotein E4 (APOE4) are the two biggest risk factors for AD. Recent AD therapeutic development has mostly benefited the patient population with milder symptoms while causing serious side effects in APOE4 carriers, leaving the most impacted patients’ group - aged APOE4 carriers with no treatment option. With the increasing aging population, there is an urgent need for a …

Znf397 Deficiency Triggers Tet2-Driven Lineage Plasticity And Ar-Targeted Therapy Resistance In Prostate Cancer, Yaru Xu, Yuqiu Yang, Zhaoning Wang, Martin Sjöström, Yuyin Jiang, Yitao Tang, Siyuan Cheng, Su Deng, Choushi Wang, Julisa Gonzalez, Nickolas A Johnson, Xiang Li, Xiaoling Li, Lauren A Metang, Atreyi Mukherji, Quanhui Xu, Carla R Tirado, Garrett Wainwright, Xinzhe Yu, Spencer Barnes, Mia Hofstad, Yu Chen, Hong Zhu, Ariella B Hanker, Ganesh V Raj, Guanghui Zhu, Housheng H He, Zhao Wang, Carlos L Arteaga, Han Liang, Felix Y Feng, Yunguan Wang, Tao Wang, Ping Mu

Faculty, Staff and Students Publications

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming that allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified zinc finger protein 397 (ZNF397) as a bona fide coactivator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a ten-eleven translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our …

Genetic Diversity Of 1,845 Rhesus Macaques Improves Genetic Variation Interpretation And Identifies Disease Models, Jun Wang, Meng Wang, Ala Moshiri, R Alan Harris, Muthuswamy Raveendran, Tracy Nguyen, Soohyun Kim, Laura Young, Keqing Wang, Roger Wiseman, David H O'Connor, Zach Johnson, Melween Martinez, Michael J Montague, Ken Sayers, Martha Lyke, Eric Vallender, Tim Stout, Yumei Li, Sara M Thomasy, Jeffrey Rogers, Rui Chen

Faculty, Staff and Students Publications

Understanding and treating human diseases require valid animal models. Leveraging the genetic diversity in rhesus macaque populations across eight primate centers in the United States, we conduct targeted-sequencing on 1845 individuals for 374 genes linked to inherited human retinal and neurodevelopmental diseases. We identify over 47,000 single nucleotide variants, a substantial proportion of which are shared with human populations. By combining rhesus and human allele frequencies with established variant prediction methods, we develop a machine learning-based score that outperforms established methods in predicting missense variant pathogenicity. Remarkably, we find a marked number of loss-of-function variants and putative deleterious variants, which …

Cyp3a Mediates An Unusual C(Sp2)-C(Sp3) Bond Cleavage Via Ipso-Addition Of Oxygen In Drug Metabolism, Xuan Qin, Yong Wang, Qiuji Ye, John M Hakenjos, Jin Wang, Mingxing Teng, Lei Guo, Zhi Tan, Damian W Young, Kevin R Mackenzie, Feng Li

Faculty, Staff and Students Publications

Mammalian cytochrome P450 drug-metabolizing enzymes rarely cleave carbon–carbon (C-C) bonds and the mechanisms of such cleavages are largely unknown. We identified two unusual cleavages of non-polar, unstrained C(sp2)-C(sp3) bonds in the FDA-approved tyrosine kinase inhibitor pexidartinib that are mediated by CYP3A4/5, the major human phase I drug metabolizing enzymes. Using a synthetic ketone, we rule out the Baeyer-Villiger oxidation mechanism that is commonly invoked to address P450-mediated C-C bond cleavages. Our studies in 18O2 and H218O enriched systems reveal two unusual distinct mechanisms of C-C bond cleavage: one bond is cleaved by CYP3A-mediated ipso-addition of oxygen to a C(sp2) …

Protein Oxidation In Aging And Alzheimer’S Disease Brain, Rukhsana Sultana, D. Allan Butterfield

Markey Cancer Center Faculty Publications

Proteins are essential molecules that play crucial roles in maintaining cellular homeostasis and carrying out biological functions such as catalyzing biochemical reactions, structural proteins, immune response, etc. However, proteins also are highly susceptible to damage by reactive oxygen species (ROS) and reactive nitrogen species (RNS). In this review, we summarize the role of protein oxidation in normal aging and Alzheimer’s disease (AD). The major emphasis of this review article is on the carbonylation and nitration of proteins in AD and mild cognitive impairment (MCI). The oxidatively modified proteins showed a strong correlation with the reported changes in brain structure, carbohydrate …

A Combination Of Generated Hydrogen Sulfide And Nitric Oxide Activity Has A Potentiated Protectant Effect Against Cisplatin Induced Nephrotoxicity, Faria Khurshid, Javeid Iqbal, Fiaz Ud Din Ahmad, Arslan Hussain Lodhi, Abdul Malik, Suhail Akhtar, Azmat Ali Khan, Marvi Imam Bux, Mohammed Younis

Biomedical Sciences Faculty Publications

Aim: Hydrogen sulfide and nitricoxide possess cytoprotective activity and in vivo, they are generated from exogenous sodium hydrosulfide and L-arginine respectively. Cisplatin is a major chemotherapeutic agent used to treat cancer and has a high incidence of nephrotoxicity as a side effect. The study aim was to explore the effects of NaHS and L-arginine or their combination on cisplatin induced nephrotoxicity in rats. Methods: Wistar Kyoto rats were given a single intraperitoneal dose of cisplatin (5 mg/kg) followed either by NaHS (56 μmol/kg, i. p.), L-arginine (1.25 g/L in drinking water) or their combination daily for 28-days. Post-mortem plasma, urine …

Hedgehog Signaling And Congenital Disorders; The Case Of Anencephaly And Polydactyly, Joshua Towery

First-Year Research Immersion (FRI) Scholarship

The Hedgehog pathway is a fundamental signaling pathway in the human body; involved in carcinogenesis, stem cell maintenance, as well as limb patterning in embryonic development. Originally discovered in drosophila, their initial discovery, and subsequent analysis revealed many novel pieces of information about the mechanisms inside the human body, as many core components of the signaling pathway are carried over from fruit flies to humans. Because of the key roles hedgehog signaling plays in human development, dysfunction and mutations in the pathway can be detrimental. This review will focus on two congenital birth defects thought to be caused by hedgehog …

Cyclophilin A Supports Translation Of Intrinsically Disordered Proteins And Affects Haematopoietic Stem Cell Ageing, Laure Maneix, Polina Iakova, Charles G Lee, Shannon E Moree, Xuan Lu, Gandhar K Datar, Cedric T Hill, Eric Spooner, Jordon C K King, David B Sykes, Borja Saez, Bruno Di Stefano, Xi Chen, Daniela S Krause, Ergun Sahin, Francis T F Tsai, Margaret A Goodell, Bradford C Berk, David T Scadden, André Catic

Faculty, Staff and Students Publications

Loss of protein function is a driving force of ageing. We have identified peptidyl-prolyl isomerase A (PPIA or cyclophilin A) as a dominant chaperone in haematopoietic stem and progenitor cells. Depletion of PPIA accelerates stem cell ageing. We found that proteins with intrinsically disordered regions (IDRs) are frequent PPIA substrates. IDRs facilitate interactions with other proteins or nucleic acids and can trigger liquid-liquid phase separation. Over 20% of PPIA substrates are involved in the formation of supramolecular membrane-less organelles. PPIA affects regulators of stress granules (PABPC1), P-bodies (DDX6) and nucleoli (NPM1) to promote phase separation and increase cellular stress resistance. …

Enhancing Translation: A Need To Leverage Complex Preclinical Models Of Addictive Drugs To Accelerate Substance Use Treatment Options, Christa Corley, Ashley Craig, Safiyah M. Sadek, Julie A. Marusich, Samar N. Chehimi, Ashley M. White, Lexi J. Holdiness, Benjamin C. Reiner, Cassandra D. Gipson

Markey Cancer Center Faculty Publications

Preclinical models of addictive drugs have been developed for decades to model aspects of the clinical experience in substance use disorders (SUDs). These include passive exposure as well as volitional intake models across addictive drugs and have been utilized to also measure withdrawal symptomatology and potential neuro- behavioral mechanisms underlying relapse to drug seeking or taking. There are a number of Food and Drug Administration (FDA)-approved medications for SUDs, however, many demonstrate low clinical efficacy as well as potential sex differences, and we also note gaps in the continuum of care for certain aspects of clinical ex- periences in individuals …

Effects Of Dimerization On The Deacylase Activities Of Human Sirt2., Jie Yang, Nathan I Nicely, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Human sirtuin isoform 2 (SIRT2) is an NAD+-dependent enzyme that functions as a lysine deacetylase and defatty-acylase. Here, we report that SIRT2 readily dimerizes in solution and in cells and that dimerization affects its ability to remove different acyl modifications from substrates. Dimerization of recombinant SIRT2 was revealed with analytical size exclusion chromatography and chemical cross-linking. Dimerized SIRT2 dissociates into monomers upon binding long fatty acylated substrates (decanoyl-, dodecanoyl-, and myristoyl-lysine). However, we did not observe dissociation of dimeric SIRT2 in the presence of acetyl-lysine. Analysis of X-ray crystal structures led us to discover a SIRT2 double mutant (Q142A/E340A) that …

Design Of An Fgf-1-Fgf-2 Heterodimer Variant With Enhanced Stability And Cell Proliferation Activity, Nicholas Alan Pohlman

Chemistry & Biochemistry Undergraduate Honors Theses

The FGF-1 subfamily, composed of FGF-1 and FGF-2, assists in broad health-related processes such as cell proliferation and angiogenesis respectively.^1,2 The subfamily shows promising signs as a therapeutic, however, the inherent thermal instability leads to a low half-life in vivo.³ To assist in improving the stability, FGF-1 and FGF-2 were connected via a 12-residue glycine linker ultimately producing a heterodimer. This heterodimer was further examined to discover its novel properties. Inspiration for this project was drawn from previous research which performed five mutations on FGF-1 ultimately improving stability in the protein complex. In addition to these five …

Advancing Asms With Lc-Ms/Ms For The Discovery Of Novel Pdcl2 Ligands From Dna-Encoded Chemical Library Selections, Qiuji Ye, Hassane Belabed, Yong Wang, Zhifeng Yu, Murugesan Palaniappan, Jian-Yuan Li, Stacey A Kalovidouris, Kevin R Mackenzie, Mingxing Teng, Damian W Young, Yoshitaka Fujihara, Martin M Matzuk

Faculty, Staff and Students Publications

BACKGROUND: A safe, effective, and reversible nonhormonal male contraceptive drug is greatly needed for male contraception as well as for circumventing the side effects of female hormonal contraceptives. Phosducin-like 2 (PDCL2) is a testis-specific phosphoprotein in mice and humans. We recently found that male PDCL2 knockout mice are sterile due to globozoospermia caused by impaired sperm head formation, indicating that PDCL2 is a potential target for male contraception. Herein, our study for the first time developed a biophysical assay for PDCL2 allowing us to screen a series of small molecules, to study structure-activity relationships, and to discover two PDCL2 binders …

Magnesium Increases Numbers Of Foxp3+ Treg Cells And Reduces Arthritis Severity And Joint Damage In An Il-10-Dependent Manner Mediated By The Intestinal Microbiome, Teresina Laragione, Carolyn Harris, Nasim Azizgolshani, Christine Beeton, Gerold Bongers, Percio S Gulko

Faculty, Staff and Students Publications

BACKGROUND: Rheumatoid arthritis (RA) is a common autoimmune disease with emerging environmental and microbiome risk factors. The western diet is typically deficient in magnesium (Mg), and there is some evidence suggesting that Mg may have anti-inflammatory properties. But the actual role of Mg supplementation in arthritis or in T cell subsets has not been explored.

METHODS: We investigated the role of a high Mg diet in two different mouse models of RA induced with the KRN serum, and collagen-induced arthritis. We also characterized the phenotypes of splenocytes, gene expression, and an extensive intestinal microbiome analyses including fecal material transplantation (FMT). …

Nicotinamide Riboside And Beta-Hydroxybutyrate Activate Parallel Pathways For C. Elegans Lifespan Extension, Mckenzie Peters

Undergraduate Honors Theses

Supplementation with nicotinamide riboside (NR), a form of vitamin B3 and a precursor of nicotinamide adenine dinucleotide (NAD⁺) extends lifespan in the nematode C. elegans and delays aging-related pathologies in mammals. During aging, levels of NAD⁺ decline causing metabolic dysfunction and oxidative damage. Studies in C. elegans found that when NR was administered during larval development it induced the mitochondrial unfolded protein response (UPR^mt), which is frequently associated with lifespan extension. Both calorie restriction (CR) and ketogenic diets (KD) have been shown to extend lifespan, in part through increasing NAD⁺ and through increasing levels …

Loss Of Peroxiredoxin Iv Protects Mice From Azoxymethane/Dextran Sulfate Sodium-Induced Colorectal Cancer Development, Pratik Thapa, Hong Jiang, Na Ding, Yanning Hao, Aziza Alshahrani, Eun Young Lee, Junichi Fujii, Qiou Wei

Markey Cancer Center Faculty Publications

Peroxiredoxin IV (Prx4), a typical two-cysteine-containing member of the peroxidase family, functions as an antioxidant to maintain cellular redox homeostasis through the reduction of reactive oxygen species (ROS) via cycles of oxidation–reduction reactions. Under oxidative stress, all Prxs including Prx4 are inactivated as their catalytic cysteines undergo hyperoxidation, and hyperoxidized two-cysteine Prxs can be exclusively repaired and revitalized through the reduction cycle catalyzed by sulfiredoxin (Srx). Previously, we showed that Prx4 is a preferred substrate of Srx, and knockout of Srx in mice leads to resistance to azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis. To further understand the significance of the …

Observing Ceramide Pathway With Ferroptosis Via Mia Paca-2 Cell Treatment With Rsl3, Tazrin Rahman

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Composed of sphingosine and a fatty acid, ceramides are lipid molecules that serve as key metabolic signaling molecules of a sphingolipid pathway. While it acts as a precursor of complex sphingolipids, inducing ceramide generation can cause cell stress leading to subsequent cell death via apoptosis, necrosis, and even mitophagy. With regards to cell death specifically, a novel form of regulated cell death, ferroptosis, has recently been recognized of necrotic nature. Its unique morphological features and distinct properties have been observed over the last several decades; however, the molecular features were not identifiable as pure evidence of cell death, until recently …

Development Of A Chemical Biology Approach To Uncover The Influence Of Sequence Variations On Ces1 Activity In Live Cells, Samuel James Knebel

Masters Theses

Drug metabolism is the biochemical process of modifying drugs to detoxify and remove them through enzymatic transformations. These biotransformation’s occur primarily in the liver and are critical to understanding how pharmaceutical compounds are chemically altered inside the human body. Human carboxylesterases (CESs) catalyze the hydrolysis of esters, amides, thioesters, and carbamates. CES-mediated hydrolysis plays an important role in the metabolism of many drugs including the first FDA approved antiviral treatment for COVID-19, remdesivir (Veklury), the seizure control medication rufinamide (Banzel), and the flu antiviral drug oseltamivir (Tamiflu). CES activity is known to be influenced by a variety of factors including …

Quantitative Measurement Of Protac Intracellular Accumulation, Xin Yu, Jin Wang

Faculty, Staff and Students Publications

In recent years, Proteolysis Targeting Chimera (PROTAC) technology has emerged as one of the most promising approaches to remove disease-associated proteins by utilizing cells' own destruction machinery. To achieve successful degradation of a protein of interest (POI), the heterobifunctional PROTAC molecules must penetrate into the cells first, followed by target engagement and formation of the POI-PROTAC-E3 ligase complex. Based on this understanding, the assessment of cell permeability and in cell target engagement are of great importance to evaluate the efficacy of PROTAC candidates. PROTAC molecules can be classified as non-covalent and covalent, and covalent PROTACs can be further divided into …

Structural Basis Of Ferroportin Inhibition By Minihepcidin Pr73, Azaan Saalim Wilbon, Jiemin Shen, Piotr Ruchala, Ming Zhou, Yaping Pan

Faculty, Staff and Students Publications

Ferroportin (Fpn) is the only known iron exporter in humans and is essential for maintaining iron homeostasis. Fpn activity is suppressed by hepcidin, an endogenous peptide hormone, which inhibits iron export and promotes endocytosis of Fpn. Hepcidin deficiency leads to hemochromatosis and iron-loading anemia. Previous studies have shown that small peptides that mimic the first few residues of hepcidin, i.e., minihepcidins, are more potent than hepcidin. However, the mechanism of enhanced inhibition by minihepcidins remains unclear. Here, we report the structure of human ferroportin in complex with a minihepcidin, PR73 that mimics the first 9 residues of hepcidin, at 2.7 …

Applications Of Covalent Chemistry In Targeted Protein Degradation, Dong Lu, Xin Yu, Hanfeng Lin, Ran Cheng, Erika Y Monroy, Xiaoli Qi, Meng C Wang, Jin Wang

Faculty, Staff and Students Publications

Proteolysis-targeting chimeras (PROTACs) and targeted covalent inhibitors (TCIs) are currently two exciting strategies in the fields of chemical biology and drug discovery. Extensive research in these two fields has been conducted, and significant progress in these fields has resulted in many clinical candidates, some of which have been approved by FDA. Recently, a novel concept termed covalent PROTACs that combine these two strategies has emerged and gained an increasing interest in the past several years. Herein, we briefly review and highlight the mechanism and advantages of TCIs and PROTACs, respectively, and the recent development of covalent PROTACs using irreversible and …

Helical Remodeling Augments 5-Lipoxygenase Activity In The Synthesis Of Proinflammatory Mediators, Eden M. Gallegos, Tanner D. Reed, Forge A. Mathes, Nelson V. Guevara, David B. Neau, Wei Huang, Marcia E. Newcomer, Nathaniel C. Gilbert

School of Medicine Faculty Publications

The synthesis of proinflammatory leukotrienes implicated in asthma, allergic rhinitis, and atherosclerosis is initiated by the enzyme 5-lipoxygenase (5-LOX). The crystal structure of human Stable-5-LOX revealed a conformation where the catalytic iron was inaccessible to bulk solvent as two aromatic residues on a conserved helix-α2 (Hα2) plugged the substrate access portal. Whether 5-LOX can also adopt a more open conformation has not been resolved. Here, we present a new conformation of 5-LOX where Hα2 adopts an elongated conformation equivalent to that described in other animal lipoxygenase structures. Our observation of the sigmoidal kinetic behavior of 5-LOX, which is indicative of …

Crispr/Cas13 Effectors Have Differing Extents Of Off-Target Effects That Limit Their Utility In Eukaryotic Cells, Yuxi Ai, Dongming Liang, Jeremy E Wilusz

Faculty, Staff and Students Publications

CRISPR/Cas13 effectors have garnered increasing attention as easily customizable tools for detecting and depleting RNAs of interest. Near perfect complementarity between a target RNA and the Cas13-associated guide RNA is required for activation of Cas13 ribonuclease activity. Nonetheless, the specificity of Cas13 effectors in eukaryotic cells has been debated as the Cas13 nuclease domains can be exposed on the enzyme surface, providing the potential for promiscuous cleavage of nearby RNAs (so-called collateral damage). Here, using co-transfection assays in Drosophila and human cells, we found that the off-target effects of RxCas13d, a commonly used Cas13 effector, can be as strong as …

Ultrasound 96 Probe Device Protocol For Cancer Cell Treatment, Aisling Field, Brijesh K. Tiwari, James F. Curtin, Julie R M Mondala, Janith Wanigasekara

Articles

Ultrasound is a sound wave with frequencies ranging between 20 kHz and 20 MHz. Ultrasound is able to temporarily and repeatedly open the BBB safely and enhance chemotherapeutic delivery without adverse effects. This novel technique in drug delivery benefits from the powerful ability of ultrasound to produce cavitation activity. Cavitation is the generation and activity of gas-filled bubbles in a medium exposed to ultrasound. As the pressure wave passes through the media, gas bubbles expand at low pressure and contract at high pressure. This leads to oscillation which produces a circulating fluid flow known as microstreaming around the bubble with …