Medical Biochemistry Commons^™

Bispecific Bcma/Cd24 Car-T Cells Control Multiple Myeloma Growth, Fumou Sun, Yan Cheng, Visanu Wanchai, Wancheng Guo, David Mery, Hongwei Xu, Dongzheng Gai, Eric Siegel, Clyde Bailey, Cody Ashby, Samer Al Hadidi, Carolina Schinke, Sharmilan Thanendrarajan, Yupo Ma, Qing Yi, Robert Z Orlowski, Maurizio Zangari, Frits Van Rhee, Siegfried Janz, Gail Bishop, Guido Tricot, John D Shaughnessy, Fenghuang Zhan

Faculty, Staff and Student Publications

Anti-multiple myeloma B cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapies represent a promising treatment strategy with high response rates in myeloma. However, durable cures following anti-BCMA CAR-T cell treatment of myeloma are rare. One potential reason is that a small subset of minimal residual myeloma cells seeds relapse. Residual myeloma cells following BCMA-CAR-T-mediated treatment show less-differentiated features and express stem-like genes, including CD24. CD24-positive myeloma cells represent a large fraction of residual myeloma cells after BCMA-CAR-T therapy. In this work, we develop CD24-CAR-T cells and test their ability to eliminate myeloma cells. We find that CD24-CAR-T cells …

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 …

Hnf4Α Isoforms Regulate The Circadian Balance Between Carbohydrate And Lipid Metabolism In The Liver, Jonathan R Deans, Poonamjot Deol, Nina Titova, Sarah H Radi, Linh M Vuong, Jane R Evans, Songqin Pan, Johannes Fahrmann, Jun Yang, Bruce D Hammock, Oliver Fiehn, Baharan Fekry, Kristin Eckel-Mahan, Frances M Sladek

Faculty, Staff and Student Publications

Hepatocyte Nuclear Factor 4α (HNF4α), a master regulator of hepatocyte differentiation, is regulated by two promoters (P1 and P2) which drive the expression of different isoforms. P1-HNF4α is the major isoform in the adult liver while P2-HNF4α is thought to be expressed only in fetal liver and liver cancer. Here, we show that P2-HNF4α is indeed expressed in the normal adult liver at Zeitgeber time (ZT)9 and ZT21. Using exon swap mice that express only P2-HNF4α we show that this isoform orchestrates a distinct transcriptome and metabolome via unique chromatin and protein-protein interactions, including with different clock proteins at different …

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 …

Localization, Tissue Biology, And T Cell State — Implications For Cancer Immunotherapy, Jason M Schenkel, Kristen E Pauken

Faculty, Staff and Student Publications

Tissue localization is a critical determinant of T cell immunity. CD8+ T cells are contact-dependent killers, which requires them to physically be within the tissue of interest to kill peptide-MHC class I-bearing target cells. Following their migration and extravasation into tissues, T cells receive many extrinsic cues from the local microenvironment, and these signals shape T cell differentiation, fate and function. Because major organ systems are variable in their functions and compositions, they apply disparate pressures on T cells to adapt to the local microenvironment. Additional complexity arises in the context of malignant lesions (either primary or metastatic), and this …

Loss Of The Methylarginine Reader Function Of Snd1 Confers Resistance To Hepatocellular Carcinoma, Tanner Wright, Yalong Wang, Sabrina A Stratton, Manu Sebastian, Bin Liu, David G Johnson, Mark T Bedford

Faculty, Staff and Student Publications

Staphylococcal nuclease Tudor domain containing 1 (SND1) protein is an oncogene that 'reads' methylarginine marks through its Tudor domain. Specifically, it recognizes methylation marks deposited by protein arginine methyltransferase 5 (PRMT5), which is also known to promote tumorigenesis. Although SND1 can drive hepatocellular carcinoma (HCC), it is unclear whether the SND1 Tudor domain is needed to promote HCC. We sought to identify the biological role of the SND1 Tudor domain in normal and tumorigenic settings by developing two genetically engineered SND1 mouse models, an Snd1 knockout (Snd1 KO) and an Snd1 Tudor domain-mutated (Snd1 KI) mouse, whose mutant SND1 can …

The Role Of Alcohol Extract Of Cranberry In Improving Serum Indices Of Experimental Metaproterenol-Induced Heart Damage In Rats, Kimia Salmasi, Ali Hassanpour, Bahram Amouoghli Tabrizi, Sina Moghaddam

Faculty, Staff and Students Publications

Cranberry offers numerous cardiovascular benefits. According to several studies, this fruit promotes the oxidation of low‐density lipoprotein, enhances high‐density lipoprotein, reduces platelet coagulation, and improves vascular activity. Albino male rats were divided into five groups (n = 5 per group). The control group received intraperitoneal administration of normal saline. The second group was injected with metaproterenol (MET) 3 days a week for 4 weeks. The third, fourth, and fifth groups were given cranberry extract in doses of 75, 100, and 150, respectively, along with heart‐damaging drugs. Blood samples were collected and sent to the laboratory on the fourth weekend …

The Use Of Prognostic Markers To Predict Disease Progression And Clinical Outcome In Monoclonal Gammopathy Of Undetermined Significance, Smouldering Multiple Myeloma And Multiple Myeloma., Róisín C. Mcmonagle

International Undergraduate Journal of Health Sciences

Multiple Myeloma (MM) is an incurable plasma cell malignancy with a complex and incompletely understood molecular pathogenesis. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smouldering Multiple Myeloma (SMM) precede MM, with variable risks and rates of disease progression. The continuing high relapse and death rate in MM cases has prompted research into more accurate prognostic markers to predict progression from MGUS and SMM to MM, as well as identify MM cases with aggressive disease, in order to begin early, targeted and effective therapeutic intervention. Many studies have focused on utilising current markers more effectively, including M-protein, serum-free light chain ratio, …

Effects Of Surface Treatment Method Forming New Nano/Micro Hierarchical Structures On Attachment And Proliferation Of Osteoblast-Like Cells, Jae-Seung Im, Hyunsuk Choi, Hyun-Wook An, Tae-Yub Kwon, Min-Ho Hong

Faculty, Staff and Student Publications

Titanium (Ti) and Ti-based alloys are commonly used in dental implants, and surface modifications of dental implants are important for achieving osseointegration (i.e., direct connection between the implant surface and bone). This study investigated the effect of an eco-friendly etching solution-a hydrogen peroxide-sodium bicarbonate mixture-on the surface properties and contact angles of osteoblast adhesion and proliferation on Ti surfaces. Disk-shaped Ti specimens were prepared using different surface treatments (machining, sandblasting, and sandblasting/acid-etching), and they were immersed in the etching solution and ultrasonically cleaned. Surface characterization was performed using scanning electron microscopy, digital microscopy, contact angle analysis, and X-ray photoelectron spectroscopy. …

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 …

Repair Of Noise-Induced Damage To Stereocilia F-Actin Cores Is Facilitated By Xirp2 And Its Novel Mechanosensor Domain, Elizabeth L Wagner, Jun-Sub Im, Stefano Sala, Maura I Nakahata, Terence E Imbery, Sihan Li, Daniel Chen, Katherine Nimchuk, Yael Noy, David W Archer, Wenhao Xu, George Hashisaki, Karen B Avraham, Patrick W Oakes, Jung-Bum Shin

Faculty, Staff and Student Publications

Prolonged exposure to loud noise has been shown to affect inner ear sensory hair cells in a variety of deleterious manners, including damaging the stereocilia core. The damaged sites can be visualized as 'gaps' in phalloidin staining of F-actin, and the enrichment of monomeric actin at these sites, along with an actin nucleator and crosslinker, suggests that localized remodeling occurs to repair the broken filaments. Herein, we show that gaps in mouse auditory hair cells are largely repaired within 1 week of traumatic noise exposure through the incorporation of newly synthesized actin. We provide evidence that Xin actin binding repeat …

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 …

Bone Marrow Endosteal Stem Cells Dictate Active Osteogenesis And Aggressive Tumorigenesis, Yuki Matsushita, Jialin Liu, Angel Ka Yan Chu, Chiaki Tsutsumi-Arai, Mizuki Nagata, Yuki Arai, Wanida Ono, Kouhei Yamamoto, Thomas L Saunders, Joshua D Welch, Noriaki Ono

Faculty, Staff and Student Publications

The bone marrow contains various populations of skeletal stem cells (SSCs) in the stromal compartment, which are important regulators of bone formation. It is well-described that leptin receptor (LepR)+ perivascular stromal cells provide a major source of bone-forming osteoblasts in adult and aged bone marrow. However, the identity of SSCs in young bone marrow and how they coordinate active bone formation remains unclear. Here we show that bone marrow endosteal SSCs are defined by fibroblast growth factor receptor 3 (Fgfr3) and osteoblast-chondrocyte transitional (OCT) identities with some characteristics of bone osteoblasts and chondrocytes. These Fgfr3-creER-marked endosteal stromal cells contribute to …

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 …

A Complete Methyl-Lysine Binding Aromatic Cage Constructed By Two Domains Of Phf2, John R Horton, Jujun Zhou, Qin Chen, Xing Zhang, Mark T Bedford, Xiaodong Cheng

Faculty, Staff and Student Publications

The N-terminal half of PHF2 harbors both a plant homeodomain (PHD) and a Jumonji domain. The PHD recognizes both histone H3 trimethylated at lysine 4 and methylated nonhistone proteins including vaccinia-related kinase 1 (VRK1). The Jumonji domain erases the repressive dimethylation mark from histone H3 lysine 9 (H3K9me2) at select promoters. The N-terminal amino acid sequences of H3 (AR2TK4) and VRK1 (PR2VK4) bear an arginine at position 2 and lysine at position 4. Here, we show that the PHF2 N-terminal half binds to H3 and VRK1 peptides containing K4me3, with dissociation constants (KD values) of 160 nM and 42 nM, …

Sgc-Camkk2-1: A Chemical Probe For Camkk2, Carrow Wells, Yi Liang, Thomas L Pulliam, Chenchu Lin, Dominik Awad, Benjamin Eduful, Sean O'Byrne, Mohammad Anwar Hossain, Carolina Moura Costa Catta-Preta, Priscila Zonzini Ramos, Opher Gileadi, Carina Gileadi, Rafael M Couñago, Brittany Stork, Christopher G Langendorf, Kevin Nay, Jonathan S Oakhill, Debarati Mukherjee, Luigi Racioppi, Anthony R Means, Brian York, Donald P Mcdonnell, John W Scott, Daniel E Frigo, David H Drewry

Faculty, Staff and Student Publications

The serine/threonine protein kinase calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) plays critical roles in a range of biological processes. Despite its importance, only a handful of inhibitors of CAMKK2 have been disclosed. Having a selective small molecule tool to interrogate this kinase will help demonstrate that CAMKK2 inhibition can be therapeutically beneficial. Herein, we disclose SGC-CAMKK2-1, a selective chemical probe that targets CAMKK2.

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 …

Clinicopathological And Prognostic Significance Of Cxcr4 Expression In Osteosarcoma: A Meta-Analysis, I Gusti Ngurah Ananda Wira Kusuma, Grace Yulia Alphani Yapson, John Nolan, I Gede Eka Wiratnaya, I Gede Putu Supadmanaba

BioMedicine

Background: The C-X-C Motif Chemokine Receptor (CXCR4) is an oncogene that has been widely studied and associated with worse clinicopathological features and prognosis outcomes in many types of cancer. Besides that, significance of CXCR4 expression on clinicopathological features and prognostic factors in osteosarcoma (OS) requires further validation.

Aim: We conducted a meta-analysis to evaluate the association between positive CXCR4 expression with clinicopathological features and prognosis in OS.

Methods: Literature searches on Pubmed, Cochrane Library, and Web of Science were conducted systematically up to December 2021 to find relevant references. The effects of CXCR4 expression on clinicopathological characteristics and prognostic were …

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 …

Oral Nanomedicines For Sirna Delivery To Treat Inflammatory Bowel Disease, Jongyoon Shinn, Juyeon Lee, Seon Ah Lee, Seon Ju Lee, Ah Hyun Choi, Jung Seo Kim, Su Jin Kim, Hyo Jin Kim, Cherin Lee, Yejin Kim, Joohyeon Kim, Jonghee Choi, Byungchae Jung, Taeho Kim, Hyeontaek Nam, Hyungjun Kim, Yonghyun Lee

Faculty, Staff and Student Publications

RNA interference (RNAi) therapies have significant potential for the treatment of inflammatory bowel diseases (IBD). Although administering small interfering RNA (siRNA) via an oral route is desirable, various hurdles including physicochemical, mucus, and cellular uptake barriers of the gastrointestinal tract (GIT) impede both the delivery of siRNA to the target site and the action of siRNA drugs at the target site. In this review, we first discuss various physicochemical and biological barriers in the GI tract. Furthermore, we present recent strategies and the progress of oral siRNA delivery strategies to treat IBD. Finally, we consider the challenges faced in the …

Turning Nonselective Inhibitors Of Type I Protein Arginine Methyltransferases Into Potent And Selective Inhibitors Of Protein Arginine Methyltransferase 4 Through A Deconstruction-Reconstruction And Fragment-Growing Approach, Giulia Iannelli, Ciro Milite, Nils Marechal, Vincent Cura, Luc Bonnefond, Nathalie Troffer-Charlier, Alessandra Feoli, Donatella Rescigno, Yalong Wang, Alessandra Cipriano, Monica Viviano, Mark T Bedford, Jean Cavarelli, Sabrina Castellano, Gianluca Sbardella

Faculty, Staff and Student Publications

Protein arginine methyltransferases (PRMTs) are important therapeutic targets, playing a crucial role in the regulation of many cellular processes and being linked to many diseases. Yet, there is still much to be understood regarding their functions and the biological pathways in which they are involved, as well as on the structural requirements that could drive the development of selective modulators of PRMT activity. Here we report a deconstruction-reconstruction approach that, starting from a series of type I PRMT inhibitors previously identified by us, allowed for the identification of potent and selective inhibitors of PRMT4, which regardless of the low cell …

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 …

Subtype-Selective Positive Modulation Of KCa2.3 Channels Increases Cilia Length, Young-Woo Nam, Rajasekharreddy Pala, Naglaa Salem El-Sayed, Denisse Laren-Henriquez, Farideh Amirrad, Grace Yang, Mohammad Asikur Rahman, Razan Orfali, Myles Downey, Keykavous Parang, Surya M. Nauli, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca²⁺-activated potassium (K_Ca2.x) channels are gated exclusively by intracellular Ca²⁺. The activation of K_Ca2.3 channels induces hyperpolarization, which augments Ca²⁺ signaling in endothelial cells. Cilia are specialized Ca²⁺ signaling compartments. Here, we identified compound 4 that potentiates human K_Ca2.3 channels selectively. The subtype selectivity of compound 4 for human K_Ca2.3 over rat K_Ca2.2a channels relies on an isoleucine residue in the HA/HB helices. Positive modulation of K_Ca2.3 channels by compound 4 increased flow-induced Ca²⁺ signaling and cilia length, while negative …

Screening Tcf19 And Kif18b To Determine Co-Regulation With Mybl1 In Triple Negative Breast Cancer Patient Tissues, Tyra Sharda Ivory

Theses (2016-Present)

The aggressive behavior in triple-negative breast cancer (TNBC) is due to genetic signaling events, which call for the comprehensive analyses of genes differentially regulated in the cancers. Our laboratory previously found that MYBL1 was over-expressed in a fraction of the TNBC, compared to some luminal, and other breast cancer subtypes. The MYBL1 gene is a proto-oncogene that serves as a strong transcriptional activator. The gene is involved in signaling events related to cell cycle signaling, differentiation, proliferation, and apoptosis, all which are differentially regulated in cancers. Because MYBL1 is a transcription regulator, involved in cancer-related mechanisms and differentially expressed in …

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 …