Biochemistry, Biophysics, and Structural Biology Commons^™

The Role Of Slc7a11 In Controlling Extracellular And Intracellular Redox Environments Of Lung Fibroblasts - Potential Targets For Intervention In Aging And Idiopathic Pulmonary Fibrosis., Yuxuan Zheng

Electronic Theses and Dissertations

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by extracellular matrix deposition by fibroblasts. Aging and oxidative stress increase the susceptibility to IPF. Redox couples, cysteine/cystine (Cys/CySS) and glutathione/glutathione disulfide (GSH/GSSG), and their redox potentials (E_h) quantify oxidative stress. Fibroblasts from old mice maintain more oxidized extracellular E_h(Cys/CySS) than young mice. Microarray shows down-regulation of Slc7a11 potentially mediates this age-related oxidation. Slc7a11 is the key component of system X_c^-, an antiporter that imports CySS and exports glutamate. The first aim of this dissertation is to investigate the mechanistic link between Slc7a11 …

Structure And Mechanism Of Human Diacylglycerol O-Acyltransferase 1, Lie Wang, Hongwu Qian, Yin Nian, Yimo Han, Zhenning Ren, Hanzhi Zhang, Liya Hu, B V Venkataram Prasad, Arthur Laganowsky, Nieng Yan, Ming Zhou

Faculty, Staff and Students Publications

Diacylglycerol O-acyltransferase-1 (DGAT1) synthesizes triacylglycerides and is required for dietary fat absorption and fat storage in humans1. DGAT1 belongs to the superfamily of membrane-bound O-acyltransferases (MBOAT) that are found in all kingdoms of life and involved in acylation of lipids and proteins2,3. It remains unclear how human DGAT1 (hDGAT1) or other mammalian members of the MBOAT family recognize their substrates and catalyze their reactions. The absence of three-dimensional structures also hampers rational targeting of hDGAT1 for therapeutic purposes. Here we present the structure of hDGAT1 in complex with a substrate oleoyl Coenzyme A solved …

Meeting Radiation Dosimetry Capacity Requirements Of Population-Scale Exposures By Geostatistical Sampling., Peter K Rogan, Eliseos J Mucaki, Ruipeng Lu, Ben C Shirley, Edward Waller, Joan H M Knoll

Biochemistry Publications

BACKGROUND: Accurate radiation dose estimates are critical for determining eligibility for therapies by timely triaging of exposed individuals after large-scale radiation events. However, the universal assessment of a large population subjected to a nuclear spill incident or detonation is not feasible. Even with high-throughput dosimetry analysis, test volumes far exceed the capacities of first responders to measure radiation exposures directly, or to acquire and process samples for follow-on biodosimetry testing.

AIM: To significantly reduce data acquisition and processing requirements for triaging of treatment-eligible exposures in population-scale radiation incidents.

METHODS: Physical radiation plumes modelled nuclear detonation scenarios of simulated exposures at …

Process Monitoring Of Moisture Content And Mass Transfer Rate In A Fluidised Bed With A Low Cost Inline Mems Nir Sensor, Claudio R Avila, Joan Ferré, Rodrigo Rocha De Oliveira, Anna De Juan, Wayne E Sinclair, Faiz M Mahdi, Ali Hassanpour, Timothy N Hunter, Richard A Bourne, Frans L Muller

Faculty, Staff and Students Publications

PURPOSE: The current trend for continuous drug product manufacturing requires new, affordable process analytical techniques (PAT) to ensure control of processing. This work evaluates whether property models based on spectral data from recent Fabry-Pérot Interferometer based NIR sensors can generate a high-resolution moisture signal suitable for process control.

METHODS: Spectral data and offline moisture content were recorded for 14 fluid bed dryer batches of pharmaceutical granules. A PLS moisture model was constructed resulting in a high resolution moisture signal, used to demonstrate (i) endpoint determination and (ii) evaluation of mass transfer performance.

RESULTS: The sensors appear robust with respect to …

Integrating Mouse And Human Genetic Data To Move Beyond Gwas And Identify Causal Genes In Cholesterol Metabolism, Zhonggang Li, James A Votava, Gregory J M Zajac, Jenny N Nguyen, Fernanda B Leyva Jaimes, Sophia M Ly, Jacqueline A Brinkman, Marco De Giorgi, Sushma Kaul, Cara L Green, Samantha L St Clair, Sabrina L Belisle, Julia M Rios, David W Nelson, Mary G Sorci-Thomas, William R Lagor, Dudley W Lamming, Chi-Liang Eric Yen, Brian W Parks

Faculty, Staff and Students Publications

Identifying the causal gene(s) that connects genetic variation to a phenotype is a challenging problem in genome-wide association studies (GWASs). Here, we develop a systematic approach that integrates mouse liver co-expression networks with human lipid GWAS data to identify regulators of cholesterol and lipid metabolism. Through our approach, we identified 48 genes showing replication in mice and associated with plasma lipid traits in humans and six genes on the X chromosome. Among these 54 genes, 25 have no previously identified role in lipid metabolism. Based on functional studies and integration with additional human lipid GWAS datasets, we pinpoint Sestrin1 as …

Acetylation Of Histone H3k27 Signals The Transcriptional Elongation For Estrogen Receptor Alpha, Yujing Gao, Lijia Chen, Yali Han, Fangrui Wu, Wen-Si Yang, Zheng Zhang, Tong Huo, Yingmin Zhu, Chengtai Yu, Hong Kim, Mark Lee, Zhen Tang, Kevin Phillips, Bin He, Sung Yun Jung, Yongcheng Song, Bokai Zhu, Rui-Ming Xu, Qin Feng

Faculty, Staff and Students Publications

As approximately 70% of human breast tumors are estrogen receptor α (ERα)-positive, estrogen and ERα play essential roles in breast cancer development. By interrupting the ERα signaling pathway, endocrine therapy has been proven to be an effective therapeutic strategy. In this study, we identified a mechanism by which Transcription Start Site (TSS)-associated histone H3K27 acetylation signals the Super Elongation Complex (SEC) to regulate transcriptional elongation of the ESR1 (ERα) gene. SEC interacts with H3K27ac on ESR1 TSS through its scaffold protein AFF4. Depletion of AFF4 by siRNA or CRISPR/Cas9 dramatically reduces expression of ESR1 and its target genes, consequently inhibiting …

Principles Of Rna Processing From Analysis Of Enhanced Clip Maps For 150 Rna Binding Proteins, Eric L Van Nostrand, Gabriel A Pratt, Brian A Yee, Emily C Wheeler, Steven M Blue, Jasmine Mueller, Samuel S Park, Keri E Garcia, Chelsea Gelboin-Burkhart, Thai B Nguyen, Ines Rabano, Rebecca Stanton, Balaji Sundararaman, Ruth Wang, Xiang-Dong Fu, Brenton R Graveley, Gene W Yeo

Faculty, Staff and Students Publications

BACKGROUND: A critical step in uncovering rules of RNA processing is to study the in vivo regulatory networks of RNA binding proteins (RBPs). Crosslinking and immunoprecipitation (CLIP) methods enable mapping RBP targets transcriptome-wide, but methodological differences present challenges to large-scale analysis across datasets. The development of enhanced CLIP (eCLIP) enabled the mapping of targets for 150 RBPs in K562 and HepG2, creating a unique resource of RBP interactomes profiled with a standardized methodology in the same cell types.

RESULTS: Our analysis of 223 eCLIP datasets reveals a range of binding modalities, including highly resolved positioning around splicing signals and mRNA …

Phosphoinositides In Retinal Function And Disease, Theodore G Wensel

Faculty, Staff and Students Publications

Phosphatidylinositol and its phosphorylated derivatives, the phosphoinositides, play many important roles in all eukaryotic cells. These include modulation of physical properties of membranes, activation or inhibition of membrane-associated proteins, recruitment of peripheral membrane proteins that act as effectors, and control of membrane trafficking. They also serve as precursors for important second messengers, inositol (1,4,5) trisphosphate and diacylglycerol. Animal models and human diseases involving defects in phosphoinositide regulatory pathways have revealed their importance for function in the mammalian retina and retinal pigmented epithelium. New technologies for localizing, measuring and genetically manipulating them are revealing new information about their importance for the …

Impedance Analysis Of Tissues In Nspef Treatment For Cancer Therapy, Edwin Ayobami Oshin

Biomedical Engineering Theses & Dissertations

Nanosecond pulsed electric field (nsPEF) for cancer therapy is characterized by applications of high voltage pulses with low pulsed energy to induce non-thermal effects on tissues such as tumor ablation. It nonthermally treats tissues via electroporation. Electroporation is the increase in permeabilization of a cell membrane due to the application of high pulsed electric field. The objective of this study was to investigate the effect of nsPEF on tissue by monitoring the tissue’s impedance in real-time. Potato slices (both untreated and electroporated), and tumors extracted from female BALBc mice were studied. 100ns, 1-10kV pulses were applied to the tissues using …

An In Vivo Genome-Wide Crispr Screen Identifies The Rna-Binding Protein Staufen2 As A Key Regulator Of Myeloid Leukemia, Jeevisha Bajaj, Michael Hamilton, Yutaka Shima, Kendall Chambers, Kyle Spinler, Eric L Van Nostrand, Brian A Yee, Steven M Blue, Michael Chen, David Rizzeri, Charles Chuah, Vivian G Oehler, H Elizabeth Broome, Roman Sasik, James Scott-Browne, Anjana Rao, Gene W Yeo, Tannishtha Reya

Faculty, Staff and Students Publications

Aggressive myeloid leukemias such as blast crisis chronic myeloid leukemia and acute myeloid leukemia remain highly lethal. Here we report a genome-wide in vivo CRISPR screen to identify new dependencies in this disease. Among these, RNA-binding proteins (RBPs) in general, and the double-stranded RBP Staufen2 (Stau2) in particular, emerged as critical regulators of myeloid leukemia. In a newly developed knockout mouse, loss of Stau2 led to a profound decrease in leukemia growth and improved survival in mouse models of the disease. Further, Stau2 was required for growth of primary human blast crisis chronic myeloid leukemia and acute myeloid leukemia. Finally, …

27 Å Cryo-Em Structure Of Rotavirus Core Protein Vp3, A Unique Capping Machine With A Helicase Activity, Dilip Kumar, Xinzhe Yu, Sue E Crawford, Rodolfo Moreno, Joanita Jakana, Banumathi Sankaran, Ramakrishnan Anish, Soni Kaundal, Liya Hu, Mary K Estes, Zhao Wang, B V Venkataram Prasad

Faculty, Staff and Students Publications

In many viruses, including rotavirus (RV), the major pathogen of infantile gastroenteritis, capping of viral messenger RNAs is a pivotal step for efficient translation of the viral genome. In RV, VP3 caps the nascent transcripts synthesized from the genomic dsRNA segments by the RV polymerase VP1 within the particle core. Here, from cryo-electron microscopy, x-ray crystallography, and biochemical analyses, we show that VP3 forms a stable tetrameric assembly with each subunit having a modular domain organization, which uniquely integrates five distinct enzymatic steps required for capping the transcripts. In addition to the previously known guanylyl- and methyltransferase activities, we show …

Defining A Taxonomy Of Intracranial Hypertension: Is Icp More Than Just A Number?, W Andrew Kofke, Swarna Rajagopalan, Diana Ayubcha, Ramani Balu, Jovany Cruz-Navarro, Panumart Manatpon, Elizabeth Mahanna-Gabrielli

Faculty, Staff and Students Publications

Intracranial pressure (ICP) monitoring and control is a cornerstone of neuroanesthesia and neurocritical care. However, because elevated ICP can be due to multiple pathophysiological processes, its interpretation is not straightforward. We propose a formal taxonomy of intracranial hypertension, which defines ICP elevations into 3 major pathophysiological subsets: increased cerebral blood volume, masses and edema, and hydrocephalus. (1) Increased cerebral blood volume increases ICP and arises secondary to arterial or venous hypervolemia. Arterial hypervolemia is produced by autoregulated or dysregulated vasodilation, both of which are importantly and disparately affected by systemic blood pressure. Dysregulated vasodilation tends to be worsened by arterial …

Provider Attitudes And Practice Patterns For Direct-Acting Antiviral Therapy For Patients With Hepatocellular Carcinoma, Nicole E Rich, Ju Dong Yang, Ponni V Perumalswami, Naim Alkhouri, Whitney Jackson, Neehar D Parikh, Neil Mehta, Reena Salgia, Andres Duarte-Rojo, Laura Kulik, Mina Rakoski, Adnan Said, Omobonike Oloruntoba, George N Ioannou, Maarouf A Hoteit, Andrew M Moon, Amol S Rangnekar, Sheila L Eswaran, Elizabeth Zheng, Janice H Jou, James Hanje, Anjana Pillai, Ruben Hernaez, Robert Wong, Steven Scaglione, Hrishikesh Samant, Devika Kapuria, Shaun Chandna, Russell Rosenblatt, Veeral Ajmera, Catherine T Frenette, Sanjaya K Satapathy, Parvez Mantry, Prasun Jalal, Binu V John, Oren K Fix, Michael Leise, Christina C Lindenmeyer, Avegail Flores, Nayan Patel, Z Gordon Jiang, Nyan Latt, Renumathy Dhanasekaran, Mobolaji Odewole, Sofia Kagan, Jorge A Marrero, Amit G Singal

Faculty, Staff and Students Publications

BACKGROUND & AIMS: Direct-acting antivirals (DAAs) are effective against hepatitis C virus and sustained virologic response is associated with reduced incidence of hepatocellular carcinoma (HCC). However, there is controversy over the use of DAAs in patients with active or treated HCC and uncertainty about optimal management of these patients. We aimed to characterize attitudes and practice patterns of hepatology practitioners in the United States regarding the use of DAAs in patients with HCC.

METHODS: We conducted a survey of hepatology providers at 47 tertiary care centers in 25 states. Surveys were sent to 476 providers and we received 279 responses …

Nr2f1 Heterozygous Knockout Mice Recapitulate Neurological Phenotypes Of Bosch-Boonstra-Schaaf Optic Atrophy Syndrome And Show Impaired Hippocampal Synaptic Plasticity, Chun-An Chen, Wei Wang, Steen E Pedersen, Ayush Raman, Michelle L Seymour, Fernanda R Ruiz, Anping Xia, Meike E Van Der Heijden, Li Wang, Jiani Yin, Joanna Lopez, Megan E Rech, Richard A Lewis, Samuel M Wu, Zhandong Liu, Fred A Pereira, Robia G Pautler, Huda Y Zoghbi, Christian P Schaaf

Faculty, Staff and Students Publications

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) has been identified as an autosomal-dominant disorder characterized by a complex neurological phenotype, with high prevalence of intellectual disability and optic nerve atrophy/hypoplasia. The syndrome is caused by loss-of-function mutations in NR2F1, which encodes a highly conserved nuclear receptor that serves as a transcriptional regulator. Previous investigations to understand the protein's role in neurodevelopment have mostly used mouse models with constitutive and tissue-specific homozygous knockout of Nr2f1. In order to represent the human disease more accurately, which is caused by heterozygous NR2F1 mutations, we investigated a heterozygous knockout mouse model and found that this model …

Metabolic Reprogramming By C-Met Inhibition As A Targetable Vulnerability In Glioblastoma, Trang Thi Thu Nguyen, Enyuan Shang, Georg Karpel-Massler, Markus D. Siegelin

Publications and Research

The elucidation of better treatments for solid tumors and especially malignant glial tumors is a priority. Better understanding of the molecular underpinnings of treatment response and resistance are critical determinants in the success for this endeavor. Recently, a battery of novel tools have surfaced that allow to interrogate tumor cell metabolism to more precise extent than this was possible in the earlier days. At the forefront of these developments are the extracellular flux and carbon tracing analyses. Through utilization of these techniques our group made the recent observation that acute and chronic c-MET inhibition drives fatty acid oxidation that in …

Discovery Of A Bacterial Peptide As A Modulator Of Glp-1 And Metabolic Disease, Catherine Tomaro-Duchesneau, Stephanie L Levalley, Daniel Roeth, Liang Sun, Frank T Horrigan, Markus Kalkum, Joseph M Hyser, Robert A Britton

Faculty, Staff and Students Publications

Early work in rodents highlighted the gut microbiota's importance in metabolic disease, including Type II Diabetes Mellitus (T2DM) and obesity. Glucagon-like peptide-1 (GLP-1), an incretin secreted by L-cells lining the gastrointestinal epithelium, has important functions: promoting insulin secretion, insulin sensitivity, and β-cell mass, while inhibiting gastric emptying and appetite. We set out to identify microbial strains with GLP-1 stimulatory activity as potential metabolic disease therapeutics. Over 1500 human-derived strains were isolated from healthy individuals and screened for GLP-1 modulation by incubating bacterial cell-free supernatants with NCI H716 L-cells. Approximately 45 strains capable of increasing GLP-1 were discovered. All GLP-1 positive …

The Sineb1 Element In The Long Non-Coding Rna Malat1 Is Necessary For Tdp-43 Proteostasis, Tuan M Nguyen, Elena B Kabotyanski, Lucas C Reineke, Jiaofang Shao, Feng Xiong, Joo-Hyung Lee, Julien Dubrulle, Hannah Johnson, Fabio Stossi, Phoebe S Tsoi, Kyoung-Jae Choi, Alexander G Ellis, Na Zhao, Jin Cao, Oluwatoyosi Adewunmi, Josephine C Ferreon, Allan Chris M Ferreon, Joel R Neilson, Michael A Mancini, Xi Chen, Jongchan Kim, Li Ma, Wenbo Li, Jeffrey M Rosen

Faculty, Staff and Students Publications

Transposable elements (TEs) comprise a large proportion of long non-coding RNAs (lncRNAs). Here, we employed CRISPR to delete a short interspersed nuclear element (SINE) in Malat1, a cancer-associated lncRNA, to investigate its significance in cellular physiology. We show that Malat1 with a SINE deletion forms diffuse nuclear speckles and is frequently translocated to the cytoplasm. SINE-deleted cells exhibit an activated unfolded protein response and PKR and markedly increased DNA damage and apoptosis caused by dysregulation of TDP-43 localization and formation of cytotoxic inclusions. TDP-43 binds stronger to Malat1 without the SINE and is likely 'hijacked' by cytoplasmic Malat1 to the …

Cell Type Composition And Circuit Organization Of Clonally Related Excitatory Neurons In The Juvenile Mouse Neocortex, Cathryn R Cadwell, Federico Scala, Paul G Fahey, Dmitry Kobak, Shalaka Mulherkar, Fabian H Sinz, Stelios Papadopoulos, Zheng H Tan, Per Johnsson, Leonard Hartmanis, Shuang Li, Ronald J Cotton, Kimberley F Tolias, Rickard Sandberg, Philipp Berens, Xiaolong Jiang, Andreas Savas Tolias

Faculty, Staff and Students Publications

Clones of excitatory neurons derived from a common progenitor have been proposed to serve as elementary information processing modules in the neocortex. To characterize the cell types and circuit diagram of clonally related excitatory neurons, we performed multi-cell patch clamp recordings and Patch-seq on neurons derived from Nestin-positive progenitors labeled by tamoxifen induction at embryonic day 10.5. The resulting clones are derived from two radial glia on average, span cortical layers 2–6, and are composed of a random sampling of transcriptomic cell types. We find an interaction between shared lineage and connection type: related neurons are more likely to …

Probable African Tick Bite Fever In The United States, Kami Lowery, Theodore Rosen

Faculty, Staff and Students Publications

African tick bite fever (ATBF) is a tick-borne rickettsial disease most often observed in North American and European tourists returning home from the southern portion of Africa. Ticks infected with Rickettsia africae transmit this parasitic bacterium to humans, who subsequently develop an influenza-like illness, one or more inoculation eschars, and in some cases, a cutaneous rash. Because ATBF often presents with non-specific symptoms that suggest other infectious diseases, establishing the diagnosis may be difficult. Confirmatory assays, including serology and nucleic acid amplification, may take weeks to return and cannot help with acute treatment decisions. We present a case of a …

The Struggling Infectious Diseases Fellow: Remediation Challenges And Opportunities, Michael T Melia, Armando Paez, Gail Reid, Lisa M Chirch, Vera P Luther, Brian G Blackburn, Federico Perez, Emily Abdoler, Daniel R Kaul, Susan Rehm, Nada Harik, Alice Barsoumian, Anna K Person, Heather Yun, J David Beckham, Susan Boruchoff, Paloma F Cariello, James B Cutrell, Christopher J Graber, Dong Heun Lee, Eileen Maziarz, Molly L Paras, Raymund R Razonable, Roseanne Ressner, Anne Chen, Brian Chow, Gerome Escota, Erica Herc, Andrew Johnson, Ryan C Maves, Obinna Nnedu, Heather Clauss, Prathit Kulkarni, Paul S Pottinger, Jose A Serpa, Tanaya Bhowmick, Marvin Bittner, Darcy Wooten, Beata Casanas, Rachel Shnekendorf, Emily A Blumberg

Faculty, Staff and Students Publications

Remediation of struggling learners is a challenge faced by all educators. In recognition of this reality, and in light of contemporary challenges facing infectious diseases (ID) fellowship program directors, the Infectious Diseases Society of America Training Program Directors' Committee focused the 2018 National Fellowship Program Directors' Meeting at IDWeek on "Remediation of the Struggling Fellow." Small group discussions addressed 7 core topics, including feedback and evaluations, performance management and remediation, knowledge deficits, fellow well-being, efficiency and time management, teaching skills, and career development. This manuscript synthesizes those discussions around a competency-based framework to provide program directors and other educators with …

Homogeneous And Functional Group Tolerant Ring-Closing Metathesis For Dna-Encoded Chemical Libraries, Olivier B C Monty, Pranavanand Nyshadham, Kurt M Bohren, Murugesan Palaniappan, Martin M Matzuk, Damian W Young, Nicholas Simmons

Faculty, Staff and Students Publications

Reaction heterogeneity, poor pH control, and catalyst decomposition in the ring-closing metathesis (RCM) of DNA–chemical conjugates lead to poor yields of the cyclized products. Herein we address these issues with a RCM reaction system that includes a novel aqueous solvent combination to enable reaction homogeneity, an acidic buffer system which masks traditionally problematic functional groups, and a decomposition-resistant catalyst which maximizes conversion to the cyclized product. Additionally, we provide a systematic study of the substrate scope of the on-DNA RCM reaction, a demonstration of its applicability to a single-substrate DNA-encoded chemical library that includes sequencing analysis, and the first successful …

A Broad-Spectrum Antiviral Molecule, Ql47, Selectively Inhibits Eukaryotic Translation, Mélissanne De Wispelaere, Margot Carocci, Dominique J Burri, William J Neidermyer, Calla M Olson, Imme Roggenbach, Yanke Liang, Jinhua Wang, Sean P J Whelan, Nathanael S Gray, Priscilla L Yang

Faculty, Staff and Students Publications

Small-molecule inhibitors of translation are critical tools to study the molecular mechanisms of protein synthesis. In this study, we sought to characterize how QL47, a host-targeted, small-molecule antiviral agent, inhibits steady-state viral protein expression. We demonstrate that this small molecule broadly inhibits both viral and host protein synthesis and targets a translation step specific to eukaryotic cells. We show that QL47 inhibits protein neosynthesis initiated by both canonical cap-driven and noncanonical initiation strategies, most likely by targeting an early step in translation elongation. Our findings thus establish QL47 as a new small-molecule inhibitor that can be utilized to probe the …

A Retrospective Matched-Cohort Study Of 3994 Lower Extremity Wounds Of Multiple Etiologies Across 644 Institutions Comparing A Bioactive Human Skin Allograft, Theraskin, Plus Standard Of Care, To Standard Of Care Alone, Geoff C Gurtner, Aimee D Garcia, Katie Bakewell, Jason B Alarcon

Faculty, Staff and Students Publications

Most chronic wounds are related to comorbidities, for which no clinical trials are performed. This retrospective propensity matched-cohort study examined data from 2 074 000 lower extremity wounds across 644 institutions to determine the effectiveness of TheraSkin plus standard of care (SOC; n = 1997) versus SOC alone (n = 1997). Multivariate modelling comparing outcomes such as healing rates, percent area reductions (PARs), amputations, recidivism, treatment completion, and medical transfers were evaluated. A higher proportion of wounds in the treatment group compared with the controls were more likely to close (68.3% versus 60.3%), particularly wounds with exposed structures (64% versus …

Losartan Rescues Inflammation-Related Mucociliary Dysfunction In Relevant Models Of Cystic Fibrosis, Michael D Kim, Nathalie Baumlin, Makoto Yoshida, Deepika Polineni, Sebastian F Salathe, Joseph K David, Charles A Peloquin, Adam Wanner, John S Dennis, Juliette Sailland, Philip Whitney, Frank T Horrigan, Juan R Sabater, William M Abraham, Matthias Salathe

Faculty, Staff and Students Publications

Rationale: Despite therapeutic progress in treating cystic fibrosis (CF) airway disease, airway inflammation with associated mucociliary dysfunction remains largely unaddressed. Inflammation reduces the activity of apically expressed large-conductance Ca²⁺-activated and voltage-dependent K⁺ (BK) channels, critical for mucociliary function in the absence of CFTR (CF transmembrane conductance regulator).

Objectives: To test losartan as an antiinflammatory therapy in CF using CF human bronchial epithelial cells and an ovine model of CF-like airway disease.

Methods: Losartan’s antiinflammatory effectiveness to rescue BK activity and thus mucociliary function was tested in vitro using primary, fully redifferentiated human airway epithelial cells homozygous for …

Potential Use Of Biotherapeutic Bacteria To Target Colorectal Cancer-Associated Taxa, Gareth Lawrence, Maire Begley, Paul D. Cotter, Caitríona M. Guinane

Department of Biological Sciences Publications

The role of the gut microbiome in human health and disease is the focus of much attention. It has been widely agreed upon that our gut bacteria play a role in host immunity, nutrient absorption, digestion, metabolism, and other key drivers of health. Furthermore, certain microbial signatures and specific taxa have also been associated with the development of diseases, such as obesity; inflammatory bowel disease; and, indeed, colorectal cancer (CRC), which is the focus of this review. By extension, such taxa represent potential therapeutic targets. In particular, the emerging human pathogen Fusobacterium nucleatum represents an important agent in CRC development …

Protein Tyrosine Phosphatase 4a3 (Ptp4a3/Prl-3) Drives Migration And Progression Of T-Cell Acute Lymphoblastic Leukemia In Vitro And In Vivo, Min Wei, Meghan G. Haney, Dylan R. Rivas, Jessica S. Blackburn

Molecular and Cellular Biochemistry Faculty Publications

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive blood cancer. There are no immunotherapies and few molecularly targeted therapeutics available for treatment of this malignancy. The identification and characterization of genes and pathways that drive T-ALL progression are critical for the development of new therapies for T-ALL. Here, we determined that the protein tyrosine phosphatase 4A3 (PTP4A3 or PRL-3) plays a critical role in T-ALL initiation and progression by promoting leukemia cell migration. PRL-3 is highly expressed in patient T-ALL samples at both the mRNA and protein levels compared to normal lymphocytes. Knock-down of PRL-3 expression using short-hairpin RNA (shRNA) …

Trka Undergoes A Tetramer-To-Dimer Conversion To Open Trkh Which Enables Changes In Membrane Potential, Hanzhi Zhang, Yaping Pan, Liya Hu, M Ashley Hudson, Katrina S Hofstetter, Zhichun Xu, Mingqiang Rong, Zhao Wang, B V Venkataram Prasad, Steve W Lockless, Wah Chiu, Ming Zhou

Faculty, Staff and Students Publications

TrkH is a bacterial ion channel implicated in K+ uptake and pH regulation. TrkH assembles with its regulatory protein, TrkA, which closes the channel when bound to ADP and opens it when bound to ATP. However, it is unknown how nucleotides control the gating of TrkH through TrkA. Here we report the structures of the TrkH-TrkA complex in the presence of ADP or ATP. TrkA forms a tetrameric ring when bound to ADP and constrains TrkH to a closed conformation. The TrkA ring splits into two TrkA dimers in the presence of ATP and releases the constraints on TrkH, resulting …

The Mitochondrial Hsp90 Paralog Trap1 Forms An Oxphos-Regulated Tetramer And Is Involved In Mitochondrial Metabolic Homeostasis, Abhinav Joshi, Li Dai, Yanxin Liu, Jungsoon Lee, Nastaran Mohammadi Ghahhari, Gregory Segala, Kristin Beebe, Lisa M Jenkins, Gaelyn C Lyons, Lilia Bernasconi, Francis T F Tsai, David A Agard, Len Neckers, Didier Picard

Faculty, Staff and Students Publications

BACKGROUND: The molecular chaperone TRAP1, the mitochondrial isoform of cytosolic HSP90, remains poorly understood with respect to its pivotal role in the regulation of mitochondrial metabolism. Most studies have found it to be an inhibitor of mitochondrial oxidative phosphorylation (OXPHOS) and an inducer of the Warburg phenotype of cancer cells. However, others have reported the opposite, and there is no consensus on the relevant TRAP1 interactors. This calls for a more comprehensive analysis of the TRAP1 interactome and of how TRAP1 and mitochondrial metabolism mutually affect each other.

RESULTS: We show that the disruption of the gene for TRAP1 in …

Rhoa-Rock Signaling As A Therapeutic Target In Traumatic Brain Injury, Shalaka Mulherkar, Kimberley F Tolias

Faculty, Staff and Students Publications

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide. TBIs, which range in severity from mild to severe, occur when a traumatic event, such as a fall, a traffic accident, or a blow, causes the brain to move rapidly within the skull, resulting in damage. Long-term consequences of TBI can include motor and cognitive deficits and emotional disturbances that result in a reduced quality of life and work productivity. Recovery from TBI can be challenging due to a lack of effective treatment options for repairing TBI-induced neural damage and alleviating functional impairments. Central nervous system (CNS) …

Development And Characterization Of A Wee1 Kinase Degrader, Zhengnian Li, Benika J Pinch, Calla M Olson, Katherine A Donovan, Radosław P Nowak, Caitlin E Mills, David A Scott, Zainab M Doctor, Nicholas A Eleuteri, Mirra Chung, Peter K Sorger, Eric S Fischer, Nathanael S Gray

Faculty, Staff and Students Publications

The G1/S cell cycle checkpoint is frequently dysregulated in cancer, leaving cancer cells reliant on a functional G2/M checkpoint to prevent excessive DNA damage. Wee1 regulates the G2/M checkpoint by phosphorylating CDK1 at Tyr15 to prevent mitotic entry. Previous drug development efforts targeting Wee1 resulted in the clinical-grade inhibitor, AZD1775. However, AZD1775 is burdened by dose-limiting adverse events, and has off-target PLK1 activity. In an attempt to overcome these limitations, we developed Wee1 degraders by conjugating AZD1775 to the cereblon (CRBN)-binding ligand, pomalidomide. The resulting lead compound, ZNL-02-096, degrades Wee1 while sparing PLK1, induces G2/M accumulation at 10-fold lower doses …