1
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Tucker SK, McHugh RE, Roe AJ. One problem, multiple potential targets: Where are we now in the development of small molecule inhibitors against Shiga toxin? Cell Signal 2024; 121:111253. [PMID: 38852937 DOI: 10.1016/j.cellsig.2024.111253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/04/2024] [Accepted: 06/06/2024] [Indexed: 06/11/2024]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are a group of enteric pathogens which carry phage-encoded Shiga toxins (Stx). STEC infections begin with severe abdominal pain and non-bloody diarrhoea, which can progress to bloody diarrhoea after approximately 4-days post-infection. In high-risk groups such as children and the elderly, patients may develop haemolytic uremic syndrome (HUS). HUS is characterised by microangiopathic haemolytic anaemia, thrombocytopenia, and in severe disease acute renal failure. Traditional antibiotics have been linked with increased toxin production due to the activation of recA-mediated bacterial stress response, resulting in poorer patient outcomes. Therefore, treatment relies on supportive therapies. Antivirulence strategies have been explored as an alternative treatment for bacterial infections and blockers of virulence factors such as the Type III Secretion System. Recent improvements in the mechanistic understanding of the Stx pathway have led to the design of inhibitors to disrupt the pathway, leading to toxin-mediated ribosome damage. However, compounds have yet to progress beyond Phase III clinical trials successfully. This review explores the progress in developing small molecule inhibitors by collating lead compounds derived from in-silico and experimental approaches.
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Affiliation(s)
- Samantha K Tucker
- School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Rebecca E McHugh
- School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Andrew J Roe
- School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, United Kingdom.
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2
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Botelho FD, Franca TCC, LaPlante SR. The Search for Antidotes Against Ricin. Mini Rev Med Chem 2024; 24:1148-1161. [PMID: 38350844 DOI: 10.2174/0113895575270509231121060105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/30/2023] [Accepted: 10/18/2023] [Indexed: 02/15/2024]
Abstract
The castor plant (Ricinus communis) is primarily known for its seeds, which contain a unique fatty acid called ricinoleic acid with several industrial and commercial applications. Castor seeds also contain ricin, a toxin considered a chemical and biological warfare agent. Despite years of investigation, there is still no effective antidote or vaccine available. However, some progress has been made, and the development of an effective treatment may be on the horizon. To provide an updated overview of this issue, we have conducted a comprehensive review of the literature on the current state of research in the fight against ricin. This review is based on the reported research and aims to address the challenges faced by researchers, as well as highlight the most successful cases achieved thus far. Our goal is to encourage the scientific community to continue their efforts in this critical search.
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Affiliation(s)
- Fernanda Diniz Botelho
- Laboratory of Molecular Modeling Applied to the Chemical and Biological Defense (LMCBD), Military Institute of Engineering, Praça General Tibúrcio 80, 22290-270, Rio de Janeiro, RJ, Brazil
| | - Tanos Celmar Costa Franca
- Laboratory of Molecular Modeling Applied to the Chemical and Biological Defense (LMCBD), Military Institute of Engineering, Praça General Tibúrcio 80, 22290-270, Rio de Janeiro, RJ, Brazil
- Université de Québec, INRS - Centre Armand-Frappier Santé Biotechnologie, 531 boulevard des Prairies, Laval, Québec, H7V 1B7, Canada
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradec Králové, Czech Republic
| | - Steven R LaPlante
- Université de Québec, INRS - Centre Armand-Frappier Santé Biotechnologie, 531 boulevard des Prairies, Laval, Québec, H7V 1B7, Canada
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3
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Madera S, Izzo F, Chervo MF, Dupont A, Chiauzzi VA, Bruni S, Petrillo E, Merin SS, De Martino M, Montero D, Levit C, Lebersztein G, Anfuso F, Roldán Deamicis A, Mercogliano MF, Proietti CJ, Schillaci R, Elizalde PV, Cordo Russo RI. Halting ErbB-2 isoforms retrograde transport to the nucleus as a new theragnostic approach for triple-negative breast cancer. Cell Death Dis 2022; 13:447. [PMID: 35534460 PMCID: PMC9084267 DOI: 10.1038/s41419-022-04855-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 12/14/2022]
Abstract
Triple-negative breast cancer (TNBC) is clinically defined by the absence of estrogen and progesterone receptors and the lack of membrane overexpression or gene amplification of receptor tyrosine kinase ErbB-2/HER2. Due to TNBC heterogeneity, clinical biomarkers and targeted therapies for this disease remain elusive. We demonstrated that ErbB-2 is localized in the nucleus (NErbB-2) of TNBC cells and primary tumors, from where it drives growth. We also discovered that TNBC expresses both wild-type ErbB-2 (WTErbB-2) and alternative ErbB-2 isoform c (ErbB-2c). Here, we revealed that the inhibitors of the retrograde transport Retro-2 and its cyclic derivative Retro-2.1 evict both WTErbB-2 and ErbB-2c from the nucleus of BC cells and tumors. Using BC cells from several molecular subtypes, as well as normal breast cells, we demonstrated that Retro-2 specifically blocks proliferation of BC cells expressing NErbB-2. Importantly, Retro-2 eviction of both ErbB-2 isoforms from the nucleus resulted in a striking growth abrogation in multiple TNBC preclinical models, including tumor explants and xenografts. Our mechanistic studies in TNBC cells revealed that Retro-2 induces a differential accumulation of WTErbB-2 at the early endosomes and the plasma membrane, and of ErbB-2c at the Golgi, shedding new light both on Retro-2 action on endogenous protein cargoes undergoing retrograde transport, and on the biology of ErbB-2 splicing variants. In addition, we revealed that the presence of a functional signal peptide and a nuclear export signal (NES), both located at the N-terminus of WTErbB-2, and absent in ErbB-2c, accounts for the differential subcellular distribution of ErbB-2 isoforms upon Retro-2 treatment. Our present discoveries provide evidence for the rational repurposing of Retro-2 as a novel therapeutic agent for TNBC.
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Affiliation(s)
- Santiago Madera
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Franco Izzo
- New York Genome Center, New York, NY, USA
- Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA
| | - María F Chervo
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Agustina Dupont
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Violeta A Chiauzzi
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Sofia Bruni
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Ezequiel Petrillo
- Universidad de Buenos Aires (UBA), Facultad de Ciencias Exactas y Naturales, Departamento de Fisiología, Biología Molecular y Celular and CONICET-UBA, Instituto de Fisiología, Biología Molecular y Neurociencias (IFIBYNE), C1428EHA, Buenos Aires, Argentina
| | - Sharon S Merin
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Mara De Martino
- Department of Radiation Oncology, Weill Cornell Medicine, New York, NY, USA
| | - Diego Montero
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Claudio Levit
- Servicio de Ginecología, Sanatorio Sagrado Corazón, Buenos Aires, Argentina
| | | | - Fabiana Anfuso
- Servicio de Ginecología, Sanatorio Sagrado Corazón, Buenos Aires, Argentina
| | - Agustina Roldán Deamicis
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - María F Mercogliano
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Cecilia J Proietti
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Roxana Schillaci
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Patricia V Elizalde
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina.
| | - Rosalía I Cordo Russo
- Laboratory of Molecular Mechanisms of Carcinogenesis and Molecular Endocrinology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina.
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4
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Rudolph MJ, Poon AY, Kavaliauskiene S, Myrann AG, Reynolds-Peterson C, Davis SA, Sandvig K, Vance DJ, Mantis NJ. Structural Analysis of Toxin-Neutralizing, Single-Domain Antibodies that Bridge Ricin's A-B Subunit Interface. J Mol Biol 2021; 433:167086. [PMID: 34089718 DOI: 10.1016/j.jmb.2021.167086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/18/2021] [Accepted: 05/27/2021] [Indexed: 01/20/2023]
Abstract
Ricin toxin kills mammalian cells with notorious efficiency. The toxin's B subunit (RTB) is a Gal/GalNAc-specific lectin that attaches to cell surfaces and promotes retrograde transport of ricin's A subunit (RTA) to the trans Golgi network (TGN) and endoplasmic reticulum (ER). RTA is liberated from RTB in the ER and translocated into the cell cytoplasm, where it functions as a ribosome-inactivating protein. While antibodies against ricin's individual subunits have been reported, we now describe seven alpaca-derived, single-domain antibodies (VHHs) that span the RTA-RTB interface, including four Tier 1 VHHs with IC50 values <1 nM. Crystal structures of each VHH bound to native ricin holotoxin revealed three different binding modes, based on contact with RTA's F-G loop (mode 1), RTB's subdomain 2γ (mode 2) or both (mode 3). VHHs in modes 2 and 3 were highly effective at blocking ricin attachment to HeLa cells and immobilized asialofetuin, due to framework residues (FR3) that occupied the 2γ Gal/GalNAc-binding pocket and mimic ligand. The four Tier 1 VHHs also interfered with intracellular functions of RTB, as they neutralized ricin in a post-attachment cytotoxicity assay (e.g., the toxin was bound to cell surfaces before antibody addition) and reduced the efficiency of toxin transport to the TGN. We conclude that the RTA-RTB interface is a target of potent toxin-neutralizing antibodies that interfere with both extracellular and intracellular events in ricin's cytotoxic pathway.
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Affiliation(s)
| | - Amanda Y Poon
- Department of Biomedical Sciences, University at Albany, Albany, NY, USA; Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
| | - Anne Grethe Myrann
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway
| | - Claire Reynolds-Peterson
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Simon A Davis
- New York Structural Biology Center, New York, NY, USA
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway
| | - David J Vance
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Nicholas J Mantis
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, USA.
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5
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Li XP, Harijan RK, Kahn JN, Schramm VL, Tumer NE. Small Molecule Inhibitors Targeting the Interaction of Ricin Toxin A Subunit with Ribosomes. ACS Infect Dis 2020; 6:1894-1905. [PMID: 32428396 DOI: 10.1021/acsinfecdis.0c00127] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Ricin toxin A subunit (RTA) removes an adenine from the universally conserved sarcin/ricin loop (SRL) on eukaryotic ribosomes, thereby inhibiting protein synthesis. No high affinity and selective small molecule therapeutic antidotes have been reported against ricin toxicity. RTA binds to the ribosomal P stalk to access the SRL. The interaction anchors RTA to the P protein C-termini at a well-defined hydrophobic pocket, which is on the opposite face relative to the active site. The RTA ribosome binding site has not been previously targeted by small molecule inhibitors. We used fragment screening with surface plasmon resonance to identify small molecular weight lead compounds that bind RTA and defined their interactions by crystallography. We identified five fragments, which bound RTA with mid-micromolar affinity. Three chemically distinct binding fragments were cocrystallized with RTA, and crystal structures were solved. Two fragments bound at the P stalk binding site, and the third bound to helix D, a motif distinct from the P stalk binding site. All fragments bound RTA remote from the catalytic site and caused little change in catalytic site geometry. Two fragments uniquely bound at the hydrophobic pocket with affinity sufficient to inhibit the catalytic activity on eukaryotic ribosomes in the low micromolar range. The binding mode of these inhibitors mimicked the interaction of the P stalk peptide, establishing that small molecule inhibitors can inhibit RTA binding to the ribosome with the potential for therapeutic intervention.
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Affiliation(s)
- Xiao-Ping Li
- Department of Plant Biology, Rutgers, The State University of New Jersey, 59 Dudley Road, New Brunswick, New Jersey 08901, United States
| | - Rajesh K. Harijan
- Department of Biochemistry, Albert Einstein College of Medicine, Jack and Pearl Resnick Campus,1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Jennifer N. Kahn
- Department of Plant Biology, Rutgers, The State University of New Jersey, 59 Dudley Road, New Brunswick, New Jersey 08901, United States
| | - Vern L. Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, Jack and Pearl Resnick Campus,1300 Morris Park Avenue, Bronx, New York 10461, United States
| | - Nilgun E. Tumer
- Department of Plant Biology, Rutgers, The State University of New Jersey, 59 Dudley Road, New Brunswick, New Jersey 08901, United States
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6
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Zhao X, Li H, Li J, Liu K, Wang B, Wang Y, Li X, Zhong W. Novel small molecule retrograde transport blocker confers post-exposure protection against ricin intoxication. Acta Pharm Sin B 2020; 10:498-511. [PMID: 32140395 PMCID: PMC7049615 DOI: 10.1016/j.apsb.2019.08.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/05/2019] [Accepted: 08/09/2019] [Indexed: 02/09/2023] Open
Abstract
Ricin is a highly toxic type 2 ribosome-inactivating protein (RIP) which is extracted from the seeds of castor beans. Ricin is considered a potential bioterror agent and no effective antidote for ricin exists so far. In this study, by structural modification of a retrograde transport blocker Retro-2cycl, a series of novel compounds were obtained. The primary screen revealed that compound 27 has an improved anti-ricin activity compare to positive control. In vitro pre-exposure evaluation in Madin-Darby Canine Kidney (MDCK) cells demonstrated that 27 is a powerful anti-ricin compound with an EC50 of 41.05 nmol/L against one LC (lethal concentration, 5.56 ng/mL) of ricin. Further studies surprisingly indicated that 27 confers post-exposure activity against ricin intoxication. An in vivo study showed that 1 h post-exposure administration of 27 can improve the survival rate as well as delay the death of ricin-intoxicated mice. A drug combination of 27 with monoclonal antibody mAb4C13 rescued mice from one LD (lethal dose) ricin challenge and the survival rate of tested animals is 100%. These results represent, for the first time, indication that small molecule retrograde transport blocker confers both in vitro and in vivo post-exposure protection against ricin and therefore provides a promising candidate for the development of anti-ricin medicines.
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7
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Rudolph MJ, Czajka TF, Davis SA, Thi Nguyen CM, Li XP, Tumer NE, Vance DJ, Mantis NJ. Intracellular Neutralization of Ricin Toxin by Single-domain Antibodies Targeting the Active Site. J Mol Biol 2020; 432:1109-1125. [PMID: 31931008 PMCID: PMC7066583 DOI: 10.1016/j.jmb.2020.01.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/16/2019] [Accepted: 01/02/2020] [Indexed: 02/06/2023]
Abstract
The extreme potency of the plant toxin, ricin, is due to its enzymatic subunit, RTA, which inactivates mammalian ribosomes with near-perfect efficiency. Here we characterized, at the functional and structural levels, seven alpaca single-domain antibodies (VHHs) previously reported to recognize epitopes in proximity to RTA's active site. Three of the VHHs, V2A11, V8E6, and V2G10, were potent inhibitors of RTA in vitro and protected Vero cells from ricin when expressed as intracellular antibodies ("intrabodies"). Crystal structure analysis revealed that the complementarity-determining region 3 (CDR3) elements of V2A11 and V8E6 penetrate RTA's active site and interact with key catalytic residues. V2G10, by contrast, sits atop the enzymatic pocket and occludes substrate accessibility. The other four VHHs also penetrated/occluded RTA's active site, but lacked sufficient binding affinities to outcompete RTA-ribosome interactions. Intracellular delivery of high-affinity, single-domain antibodies may offer a new avenue in the development of countermeasures against ricin toxin.toxin, antibody, structure, intracellular.
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Affiliation(s)
- Michael J Rudolph
- New York Structural Biology Center, New York, NY 10027, United States.
| | - Timothy F Czajka
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, 12208, United States; Department of Biomedical Sciences, University at Albany, Albany, NY 12201, United States
| | - Simon A Davis
- New York Structural Biology Center, New York, NY 10027, United States
| | - Chi My Thi Nguyen
- New York Structural Biology Center, New York, NY 10027, United States
| | - Xiao-Ping Li
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, United States
| | - Nilgun E Tumer
- Department of Plant Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, United States
| | - David J Vance
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, 12208, United States
| | - Nicholas J Mantis
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY, 12208, United States; Department of Biomedical Sciences, University at Albany, Albany, NY 12201, United States.
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8
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Morgens DW, Chan C, Kane AJ, Weir NR, Li A, Dubreuil MM, Tsui CK, Hess GT, Lavertu A, Han K, Polyakov N, Zhou J, Handy EL, Alabi P, Dombroski A, Yao D, Altman RB, Sello JK, Denic V, Bassik MC. Retro-2 protects cells from ricin toxicity by inhibiting ASNA1-mediated ER targeting and insertion of tail-anchored proteins. eLife 2019; 8:48434. [PMID: 31674906 PMCID: PMC6858068 DOI: 10.7554/elife.48434] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 10/28/2019] [Indexed: 12/11/2022] Open
Abstract
The small molecule Retro-2 prevents ricin toxicity through a poorly-defined mechanism of action (MOA), which involves halting retrograde vesicle transport to the endoplasmic reticulum (ER). CRISPRi genetic interaction analysis revealed Retro-2 activity resembles disruption of the transmembrane domain recognition complex (TRC) pathway, which mediates post-translational ER-targeting and insertion of tail-anchored (TA) proteins, including SNAREs required for retrograde transport. Cell-based and in vitro assays show that Retro-2 blocks delivery of newly-synthesized TA-proteins to the ER-targeting factor ASNA1 (TRC40). An ASNA1 point mutant identified using CRISPR-mediated mutagenesis abolishes both the cytoprotective effect of Retro-2 against ricin and its inhibitory effect on ASNA1-mediated ER-targeting. Together, our work explains how Retro-2 prevents retrograde trafficking of toxins by inhibiting TA-protein targeting, describes a general CRISPR strategy for predicting the MOA of small molecules, and paves the way for drugging the TRC pathway to treat broad classes of viruses known to be inhibited by Retro-2.
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Affiliation(s)
- David W Morgens
- Department of Genetics, Stanford University, Stanford, United States
| | - Charlene Chan
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Andrew J Kane
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Nicholas R Weir
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Amy Li
- Department of Genetics, Stanford University, Stanford, United States
| | | | - C Kimberly Tsui
- Department of Genetics, Stanford University, Stanford, United States
| | - Gaelen T Hess
- Department of Genetics, Stanford University, Stanford, United States
| | - Adam Lavertu
- Biomedical Informatics Training Program, Stanford University, Stanford, United States
| | - Kyuho Han
- Department of Genetics, Stanford University, Stanford, United States
| | - Nicole Polyakov
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Jing Zhou
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Emma L Handy
- Department of Chemistry, Brown University, Providence, United States
| | - Philip Alabi
- Department of Chemistry, Brown University, Providence, United States
| | - Amanda Dombroski
- Department of Chemistry, Brown University, Providence, United States
| | - David Yao
- Department of Genetics, Stanford University, Stanford, United States
| | - Russ B Altman
- Department of Genetics, Stanford University, Stanford, United States.,Bioengineering, Stanford University, Stanford, United States
| | - Jason K Sello
- Department of Chemistry, Brown University, Providence, United States
| | - Vladimir Denic
- Department of Molecular and Cellular Biology, Northwest Labs, Harvard University, Cambridge, United States
| | - Michael C Bassik
- Department of Genetics, Stanford University, Stanford, United States.,Program in Cancer Biology, Stanford University, Stanford, United States.,Stanford University Chemistry, Engineering, and Medicine for Human Health (ChEM-H), Stanford, United States
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9
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Maisel S, Broka D, Schroeder J. Intravesicular epidermal growth factor receptor subject to retrograde trafficking drives epidermal growth factor-dependent migration. Oncotarget 2017; 9:6463-6477. [PMID: 29464085 PMCID: PMC5814225 DOI: 10.18632/oncotarget.23766] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 12/23/2017] [Indexed: 12/31/2022] Open
Abstract
The Epidermal Growth Factor Receptor (EGFR) is frequently mutated and overexpressed in metastatic cancer. Although EGFR is a transmembrane tyrosine kinase localized to the basolateral membrane in normal epithelium, it is frequently found intracellularly localized in transformed cells. We have previously demonstrated the epithelial adaptor protein mucin 1 (MUC1) alters trafficking of EGFR, inhibiting its degradation and promoting its translocation to the nucleus, where it can directly modulate gene transcription. Here, we demonstrate that MUC1 promotes the retention of EGF-bound EGFR in Early Endosome Antigen1 (EEA1)-positive vesicles while preventing its trafficking to the lysosome. These events result in the accumulation of endosomal vesicles harboring active receptor throughout the cell and a reorganization of the actin cytoskeleton. EGF-dependent cell migration and filopodia formation is reliant upon this altered trafficking, and can be prevented by blocking retrograde trafficking. Together, these results indicate that intracellular EGFR may play an essential role in cancer metastasis and a potential mechanism for the failure of therapeutic antibodies in EGFR-driven metastatic breast cancer.
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Affiliation(s)
- Sabrina Maisel
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA.,Arizona Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Derrick Broka
- Arizona Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Joyce Schroeder
- Cancer Biology Graduate Interdisciplinary Program, University of Arizona, Tucson, AZ, USA.,Arizona Cancer Center, University of Arizona, Tucson, AZ, USA.,Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA.,BIO5 Institute, University of Arizona, Tucson, AZ, USA
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10
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Retro-2 and its dihydroquinazolinone derivatives inhibit filovirus infection. Antiviral Res 2017; 149:154-163. [PMID: 29175127 DOI: 10.1016/j.antiviral.2017.11.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/17/2017] [Accepted: 11/18/2017] [Indexed: 12/31/2022]
Abstract
Members of the family Filoviridae cause severe, often fatal disease in humans, for which there are no approved vaccines and only a few experimental drugs tested in animal models. Retro-2, a small molecule that inhibits retrograde trafficking of bacterial and plant toxins inside host cells, has been demonstrated to be effective against a range of bacterial and virus pathogens, both in vitro and in animal models. Here, we demonstrated that Retro-2 and its derivatives, Retro-2.1 and compound 25, blocked infection by Ebola virus and Marburg virus in vitro. We show that the derivatives were more potent inhibitors of infection as compared to the parent compound. Pseudotyped virus assays indicated that the compounds affected virus entry into cells while virus particle localization to Niemann-Pick C1-positive compartments showed that they acted at a late step in virus entry. Our work demonstrates a potential for Retro-type drugs to be developed into anti-filoviral therapeutics.
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11
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Inhibition of Retrograde Transport Limits Polyomavirus Infection In Vivo. mSphere 2017; 2:mSphere00494-17. [PMID: 29152583 PMCID: PMC5687923 DOI: 10.1128/mspheredirect.00494-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 10/30/2017] [Indexed: 02/08/2023] Open
Abstract
PyVs can cause significant morbidity and mortality in immunocompromised individuals. No clinically efficacious anti-PyV therapeutic agents are available. A recently identified inhibitor of retrograde transport, Retro-2cycl, blocks movement of PyV virion-containing vesicles from early endosomes to the endoplasmic reticulum, an early step in the PyV life cycle. Retro-2cycl and its derivatives have been shown to inhibit infection by human PyVs in tissue culture. Here, we demonstrate that a derivative of Retro-2cycl, Retro-2.1, reduces infection by MuPyV in the kidneys of acutely infected mice. Mimicking the common clinical scenario of PyV resurgence, we further show that MuPyV levels increase in the kidneys of immunocompromised, persistently infected mice and that this increase is inhibited by Retro-2.1. These data provide the first evidence for control of a natural PyV infection in vivo by administration of an inhibitor of retrograde transport. Polyomaviruses (PyVs) silently infect most humans, but they can cause life-threatening diseases in immunocompromised individuals. The JC polyomavirus (JCPyV) induces progressive multifocal leukoencephalopathy, a severe demyelinating disease in multiple sclerosis patients receiving immunomodulatory therapy, and BK polyomavirus (BKPyV)-associated nephropathy is a major cause of kidney allograft failure. No effective anti-PyV agents are available. Several compounds have been reported to possess anti-PyV activity in vitro, but none have shown efficacy in clinical trials. Productive PyV infection involves usurping the cellular retrograde vesicular transport pathway to enable endocytosed virions to navigate to the endoplasmic reticulum where virion uncoating begins. Compounds inhibiting this pathway have been shown to reduce infection by simian virus 40 (SV40), JCPyV, and BKPyV in tissue culture. In this study, we investigated the potential of Retro-2.1, a retrograde transport inhibitor, to limit infection by mouse polyomavirus (MuPyV) in vivo. We found that Retro-2.1 significantly reduced MuPyV levels in the kidney during acute infection without affecting renal function or the MuPyV-specific CD8 T cell response. To approximate the clinical setting of PyV resurgence in immunocompromised hosts, we showed that antibody-mediated depletion of T cells in persistently infected mice elevated MuPyV levels in the kidney and that Retro-2.1 blunted this increase in virus levels. In summary, these data indicate that inhibition of retrograde vesicular transport in vivo controls infection in a natural PyV mouse model and supports development of these compounds as potential therapeutic agents for individuals at risk for human PyV-associated diseases. IMPORTANCE PyVs can cause significant morbidity and mortality in immunocompromised individuals. No clinically efficacious anti-PyV therapeutic agents are available. A recently identified inhibitor of retrograde transport, Retro-2cycl, blocks movement of PyV virion-containing vesicles from early endosomes to the endoplasmic reticulum, an early step in the PyV life cycle. Retro-2cycl and its derivatives have been shown to inhibit infection by human PyVs in tissue culture. Here, we demonstrate that a derivative of Retro-2cycl, Retro-2.1, reduces infection by MuPyV in the kidneys of acutely infected mice. Mimicking the common clinical scenario of PyV resurgence, we further show that MuPyV levels increase in the kidneys of immunocompromised, persistently infected mice and that this increase is inhibited by Retro-2.1. These data provide the first evidence for control of a natural PyV infection in vivo by administration of an inhibitor of retrograde transport.
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12
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Craig E, Huyghues-Despointes CE, Yu C, Handy EL, Sello JK, Kima PE. Structurally optimized analogs of the retrograde trafficking inhibitor Retro-2cycl limit Leishmania infections. PLoS Negl Trop Dis 2017; 11:e0005556. [PMID: 28505157 PMCID: PMC5444862 DOI: 10.1371/journal.pntd.0005556] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 05/25/2017] [Accepted: 04/05/2017] [Indexed: 11/19/2022] Open
Abstract
In infected mammalian cells, Leishmania parasites reside within specialized compartments called parasitophorous vacuoles (LPVs). We have previously shown that Retro-2, a member of a novel class of small retrograde pathway inhibitors caused reduced LPV sizes and lower parasite numbers during experimental L. mexicana sp. infections. The purpose of this study was to determine if structural analogs of Retro-2cycl reported to have superior potency in the inhibition of retrograde pathway-dependent phenomena (i.e., polyomavirus cellular infection by polyomavrius and Shiga toxin trafficking in cells) are also more effective than the parent compound at controlling Leishmania infections. In addition to their effects on LPV development, we show that two optimized analogs of Retro-2cycl, DHQZ 36 and DHQZ 36.1 limit Leishmania amazonensis infection in macrophages at EC50 of 13.63+/-2.58μM and10.57+/-2.66μM, respectively, which is significantly lower than 40.15μM the EC50 of Retro-2cycl. In addition, these analogs caused a reversal in Leishmania induced suppression of IL-6 release by infected cells after LPS activation. Moreover, we show that in contrast to Retro-2cycl that is Leishmania static, the analogs can kill Leishmania parasites in axenic cultures, which is a desirable attribute for any drug to treat Leishmania infections. Together, these studies validate and extend the published structure-activity relationship analyses of Retro-2cycl.
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Affiliation(s)
- Evan Craig
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, United States of America
| | | | - Chun Yu
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, United States of America
| | - Emma L. Handy
- Department of Chemistry, Brown University, Providence Rhode Island, United States of America
| | - Jason K. Sello
- Department of Chemistry, Brown University, Providence Rhode Island, United States of America
| | - Peter E. Kima
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, United States of America
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13
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Affiliation(s)
- Megan Garland
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | - Sebastian Loscher
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
| | - Matthew Bogyo
- Cancer
Biology Program, ‡Department of Pathology, §Department of Microbiology and Immunology, and ∥Department of
Chemical and Systems Biology, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, California 94305, United States
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14
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Kavaliauskiene S, Dyve Lingelem AB, Skotland T, Sandvig K. Protection against Shiga Toxins. Toxins (Basel) 2017; 9:E44. [PMID: 28165371 PMCID: PMC5331424 DOI: 10.3390/toxins9020044] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 12/12/2022] Open
Abstract
Shiga toxins consist of an A-moiety and five B-moieties able to bind the neutral glycosphingolipid globotriaosylceramide (Gb3) on the cell surface. To intoxicate cells efficiently, the toxin A-moiety has to be cleaved by furin and transported retrogradely to the Golgi apparatus and to the endoplasmic reticulum. The enzymatically active part of the A-moiety is then translocated to the cytosol, where it inhibits protein synthesis and in some cell types induces apoptosis. Protection of cells can be provided either by inhibiting binding of the toxin to cells or by interfering with any of the subsequent steps required for its toxic effect. In this article we provide a brief overview of the interaction of Shiga toxins with cells, describe some compounds and conditions found to protect cells against Shiga toxins, and discuss whether they might also provide protection in animals and humans.
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Affiliation(s)
- Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway.
- Center for Cancer Biomedicine, Faculty of Medicine, Oslo University Hospital, N-0379 Oslo, Norway.
| | - Anne Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway.
- Center for Cancer Biomedicine, Faculty of Medicine, Oslo University Hospital, N-0379 Oslo, Norway.
| | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway.
- Center for Cancer Biomedicine, Faculty of Medicine, Oslo University Hospital, N-0379 Oslo, Norway.
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway.
- Center for Cancer Biomedicine, Faculty of Medicine, Oslo University Hospital, N-0379 Oslo, Norway.
- Department of Biosciences, University of Oslo, N-0316 Oslo, Norway.
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15
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Dahlin JL, Nissink JWM, Francis S, Strasser JM, John K, Zhang Z, Walters MA. Post-HTS case report and structural alert: Promiscuous 4-aroyl-1,5-disubstituted-3-hydroxy-2H-pyrrol-2-one actives verified by ALARM NMR. Bioorg Med Chem Lett 2015; 25:4740-4752. [PMID: 26318992 PMCID: PMC6002837 DOI: 10.1016/j.bmcl.2015.08.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/29/2015] [Accepted: 08/06/2015] [Indexed: 12/19/2022]
Abstract
Despite its wide use, not every high-throughput screen (HTS) yields chemical matter suitable for drug development campaigns, and seldom are 'go/no-go' decisions in drug discovery described in detail. This case report describes the follow-up of a 4-aroyl-1,5-disubstituted-3-hydroxy-2H-pyrrol-2-one active from a cell-free HTS to identify small-molecule inhibitors of Rtt109-catalyzed histone acetylation. While this compound and structural analogs inhibited Rtt109-catalyzed histone acetylation in vitro, further work on this series was halted after several risk mitigation strategies were performed. Compounds with this chemotype had a poor structure-activity relationship, exhibited poor selectivity among other histone acetyltransferases, and tested positive in a β-lactamase counter-screen for chemical aggregates. Furthermore, ALARM NMR demonstrated compounds with this chemotype grossly perturbed the conformation of the La protein. In retrospect, this chemotype was flagged as a 'frequent hitter' in an analysis of a large corporate screening deck, yet similar compounds have been published as screening actives or chemical probes versus unrelated biological targets. This report-including the decision-making process behind the 'no-go' decision-should be informative for groups engaged in post-HTS triage and highlight the importance of considering physicochemical properties in early drug discovery.
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Affiliation(s)
- Jayme L Dahlin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55905, USA; Medical Scientist Training Program, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | | | - Subhashree Francis
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN 55414, USA
| | - Jessica M Strasser
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN 55414, USA
| | - Kristen John
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN 55414, USA
| | - Zhiguo Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Michael A Walters
- Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN 55414, USA.
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16
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Syntaxin 5-dependent retrograde transport to the trans-Golgi network is required for adeno-associated virus transduction. J Virol 2014; 89:1673-87. [PMID: 25410859 DOI: 10.1128/jvi.02520-14] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
UNLABELLED Intracellular transport of recombinant adeno-associated virus (AAV) is still incompletely understood. In particular, the trafficking steps preceding the release of incoming AAV particles from the endosomal system into the cytoplasm, allowing subsequent nuclear import and the initiation of gene expression, remain to be elucidated fully. Others and we previously showed that a significant proportion of viral particles are transported to the Golgi apparatus and that Golgi apparatus disruption caused by the drug brefeldin A efficiently blocks AAV serotype 2 (AAV2) transduction. However, because brefeldin A is known to exert pleiotropic effects on the entire endosomal system, the functional relevance of transport to the Golgi apparatus for AAV transduction remains to be established definitively. Here, we show that AAV2 trafficking toward the trans-Golgi network (TGN) and the Golgi apparatus correlates with transduction efficiency and relies on a nonclassical retrograde transport pathway that is independent of the retromer complex, late endosomes, and recycling endosomes. AAV2 transduction is unaffected by the knockdown of syntaxins 6 and 16, which are two major effectors in the retrograde transport of both exogenous and endogenous cargo. On the other hand, inhibition of syntaxin 5 function by small interfering RNA silencing or treatment with cyclized Retro-2 strongly decreases AAV2 transduction and transport to the Golgi apparatus. This inhibition of transduction is observed with several AAV serotypes and a number of primary and immortalized cells. Together, our data strongly suggest that syntaxin 5-mediated retrograde transport to the Golgi apparatus is a broadly conserved feature of AAV trafficking that appears to be independent of the identity of the receptors used for viral attachment. IMPORTANCE Gene therapy constitutes a promising approach for the treatment of life-threatening conditions refractory to any other form of remedy. Adeno-associated virus (AAV) vectors are currently being evaluated for the treatment of diseases such as Duchenne muscular dystrophy, hemophilia, heart failure, Parkinson's disease, and others. Despite their promise as gene delivery vehicles, a better understanding of the biology of AAV-based vectors is necessary to improve further their efficacy. AAV vectors must reach the nucleus in order to deliver their genome, and their intracellular transport is not fully understood. Here, we dissect an important step of the intracellular journey of AAV by showing that retrograde transport of capsids to the trans-Golgi network is necessary for gene delivery. We show that the AAV trafficking route differs from that of known Golgi apparatus-targeted cargos, and we raise the possibility that this nonclassical pathway is shared by most AAV variants, regardless of their attachment receptors.
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17
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Abstract
ABSTRACT
Shiga toxin (Stx)-producing
Escherichia coli
(STEC) is an etiologic agent of bloody diarrhea. A serious sequela of disease, the hemolytic uremic syndrome (HUS) may arise in up to 25% of patients. The development of HUS after STEC infection is linked to the presence of Stx. STEC strains may produce one or more Stxs, and the Stxs come in two major immunological groups, Stx1 and Stx2. A multitude of possible therapeutics designed to inhibit the actions of the Stxs have been developed over the past 30 years. Such therapeutics are important because antibiotic treatment of STEC infections is contraindicated due to an increased potential for development of HUS. The reason for the increased risk of HUS after antibiotic treatment is likely because certain antibiotics induce expression of the Stxs, which are generally associated with lysogenic bacteriophages. There are a few potential therapeutics that either try to kill STEC without inducing Stx expression or target gene expression within STEC. However, the vast majority of the treatments under development are designed to limit Stx receptor generation or to prevent toxin binding, trafficking, processing, or activity within the cell. The potential therapies described in this review include some that have only been tested in vitro and several that demonstrate efficacy in animals. The therapeutics that are currently the furthest along in development (completed phase I and II trials) are monoclonal antibodies directed against Stx1 and Stx2.
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18
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JC polyomavirus attachment, entry, and trafficking: unlocking the keys to a fatal infection. J Neurovirol 2014; 21:601-13. [PMID: 25078361 DOI: 10.1007/s13365-014-0272-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/05/2014] [Accepted: 06/30/2014] [Indexed: 10/25/2022]
Abstract
The human JC polyomavirus (JCPyV) causes a lifelong persistent infection in the reno-urinary tract in the majority of the adult population worldwide. In healthy individuals, infection is asymptomatic, while in immunocompromised individuals, the virus can spread to the central nervous system and cause a fatal demyelinating disease known as progressive multifocal leukoencephalopathy (PML). There are currently very few treatment options for this rapidly progressing and devastating disease. Understanding the basic biology of JCPyV-host cell interactions is critical for the development of therapeutic strategies to prevent or treat PML. Research in our laboratory has focused on gaining a detailed mechanistic understanding of the initial steps in the JCPyV life cycle in order to define how JCPyV selectively targets cells in the kidney and brain. JCPyV requires sialic acids to attach to host cells and initiate infection, and JCPyV demonstrates specificity for the oligosaccharide lactoseries tetrasaccharide c (LSTc) with an α2,6-linked sialic acid. Following viral attachment, JCPyV entry is facilitated by the 5-hydroxytryptamine (5-HT)2 family of serotonin receptors via clathrin-dependent endocytosis. JCPyV then undergoes retrograde transport to the endoplasmic reticulum (ER) where viral disassembly begins. A novel retrograde transport inhibitor termed Retro-2(cycl) prevents trafficking of JCPyV to the ER and inhibits both initial virus infection and infectious spread in cell culture. Understanding the molecular mechanisms by which JCPyV establishes infection will open up new avenues for the prevention or treatment of virus-induced disease.
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19
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Carney DW, Nelson CDS, Ferris BD, Stevens JP, Lipovsky A, Kazakov T, DiMaio D, Atwood WJ, Sello JK. Structural optimization of a retrograde trafficking inhibitor that protects cells from infections by human polyoma- and papillomaviruses. Bioorg Med Chem 2014; 22:4836-47. [PMID: 25087050 DOI: 10.1016/j.bmc.2014.06.053] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 06/16/2014] [Accepted: 06/23/2014] [Indexed: 12/16/2022]
Abstract
Human polyoma- and papillomaviruses are non-enveloped DNA viruses that cause severe pathologies and mortalities. Under circumstances of immunosuppression, JC polyomavirus causes a fatal demyelinating disease called progressive multifocal leukoencephalopathy (PML) and the BK polyomavirus is the etiological agent of polyomavirus-induced nephropathy and hemorrhagic cystitis. Human papillomavirus type 16, another non-enveloped DNA virus, is associated with the development of cancers in tissues like the uterine cervix and oropharynx. Currently, there are no approved drugs or vaccines to treat or prevent polyomavirus infections. We recently discovered that the small molecule Retro-2(cycl), an inhibitor of host retrograde trafficking, blocked infection by several human and monkey polyomaviruses. Here, we report diversity-oriented syntheses of Retro-2(cycl) and evaluation of the resulting analogs using an assay of human cell infections by JC polyomavirus. We defined structure-activity relationships and also discovered analogs with significantly improved potency as suppressors of human polyoma- and papillomavirus infection in vitro. Our findings represent an advance in the development of drug candidates that can broadly protect humans from non-enveloped DNA viruses and toxins that exploit retrograde trafficking as a means for cell entry.
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Affiliation(s)
- Daniel W Carney
- Department of Chemistry, Brown University, 324 Brook Street, Providence, RI 02912, United States
| | - Christian D S Nelson
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, 185 Meeting Street, Providence, RI 02912, United States
| | - Bennett D Ferris
- Department of Chemistry, Brown University, 324 Brook Street, Providence, RI 02912, United States
| | - Julia P Stevens
- Department of Chemistry, Brown University, 324 Brook Street, Providence, RI 02912, United States
| | - Alex Lipovsky
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, United States
| | - Teymur Kazakov
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, United States
| | - Daniel DiMaio
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06510, United States
| | - Walter J Atwood
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, 185 Meeting Street, Providence, RI 02912, United States
| | - Jason K Sello
- Department of Chemistry, Brown University, 324 Brook Street, Providence, RI 02912, United States.
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20
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Dahlin JL, Walters MA. The essential roles of chemistry in high-throughput screening triage. Future Med Chem 2014; 6:1265-90. [PMID: 25163000 PMCID: PMC4465542 DOI: 10.4155/fmc.14.60] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
It is increasingly clear that academic high-throughput screening (HTS) and virtual HTS triage suffers from a lack of scientists trained in the art and science of early drug discovery chemistry. Many recent publications report the discovery of compounds by screening that are most likely artifacts or promiscuous bioactive compounds, and these results are not placed into the context of previous studies. For HTS to be most successful, it is our contention that there must exist an early partnership between biologists and medicinal chemists. Their combined skill sets are necessary to design robust assays and efficient workflows that will weed out assay artifacts, false positives, promiscuous bioactive compounds and intractable screening hits, efforts that ultimately give projects a better chance at identifying truly useful chemical matter. Expertise in medicinal chemistry, cheminformatics and purification sciences (analytical chemistry) can enhance the post-HTS triage process by quickly removing these problematic chemotypes from consideration, while simultaneously prioritizing the more promising chemical matter for follow-up testing. It is only when biologists and chemists collaborate effectively that HTS can manifest its full promise.
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Affiliation(s)
- Jayme L Dahlin
- Department of Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
- Medical Scientist Training Program, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Michael A Walters
- Institute for Therapeutics Discovery & Development, University of Minnesota, Minneapolis, MN 55414, USA
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21
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Gupta N, Pons V, Noël R, Buisson DA, Michau A, Johannes L, Gillet D, Barbier J, Cintrat JC. (S)-N-Methyldihydroquinazolinones are the Active Enantiomers of Retro-2 Derived Compounds against Toxins. ACS Med Chem Lett 2014; 5:94-7. [PMID: 24900779 DOI: 10.1021/ml400457j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 12/04/2013] [Indexed: 01/08/2023] Open
Abstract
This study reports the synthesis, chromatographic separation, and pharmacological evaluation of the two enantiomers of a new compound, named Retro-2.1, active against toxins by inhibiting intracellular trafficking via the retrograde route. The absolute configuration of the bioactive enantiomer has been assigned from X-ray diffraction to the (S)-enantiomer. To date, (S)-Retro-2.1 is the most potent molecule to counteract the cytotoxic potential of ricin and Shiga toxin, with EC50 values of 23 and 54 nM, respectively.
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Affiliation(s)
- Neetu Gupta
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Valérie Pons
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Romain Noël
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - David-Alexandre Buisson
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Aurélien Michau
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Ludger Johannes
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Daniel Gillet
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Julien Barbier
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Jean-Christophe Cintrat
- CEA, iBiTec-S/SIMOPRO,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- CEA, iBiTec-S/SCBM,
CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
- U1143 INSERM, 75005 Paris, France
- Institut
Curie,
Centre de Recherche, Chemical Biology of Membranes and Therapeutic
Delivery, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
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22
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Nong G, Chen S, Xu Y, Huang L, Zou Q, Li S, Mo H, Zhu P, Cen W, Wang S. Artificial photosynthesis of oxalate and oxalate-based polymer by a photovoltaic reactor. Sci Rep 2014; 4:3572. [PMID: 24389750 PMCID: PMC3880959 DOI: 10.1038/srep03572] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Accepted: 12/02/2013] [Indexed: 12/28/2022] Open
Abstract
A photovoltaic reactor was designed for artificial photosynthesis, based on the reactions involved in high energy hydrogen atoms, which were produced from water electrolysis. Water and CO2, under the conditions studied, were converted to oxalate (H2C2O4) and a polymer. This was the first time that the oxalates and oxalate-based polymer were produced from the artificial photosynthesis process.
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Affiliation(s)
- Guangzai Nong
- Center for Sugar Engineering and Technology Research, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Shan Chen
- Center for Sugar Engineering and Technology Research, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Yuanjin Xu
- State key laboratory for conservation and utilization of subtropical agro-bioresources, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Lijie Huang
- Center for Sugar Engineering and Technology Research, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Qingsong Zou
- Center for Sugar Engineering and Technology Research, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Shiqiang Li
- Institute of Light Industry and Food Engineering, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Haitao Mo
- Center for Sugar Engineering and Technology Research, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Pingchuan Zhu
- State key laboratory for conservation and utilization of subtropical agro-bioresources, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Weijian Cen
- State key laboratory for conservation and utilization of subtropical agro-bioresources, Guangxi University, Nanning, Guangxi, 530004, P. R. China
| | - Shuangfei Wang
- Institute of Light Industry and Food Engineering, Guangxi University, Nanning, Guangxi, 530004, P. R. China
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Common pharmacophore of structurally distinct small-molecule inhibitors of intracellular retrograde trafficking of ribosome inactivating proteins. Sci Rep 2013; 3:3397. [PMID: 24292269 PMCID: PMC3844963 DOI: 10.1038/srep03397] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 11/14/2013] [Indexed: 11/28/2022] Open
Abstract
We reported previously (±)-2-(5-methylthiophen-2-yl)-3-phenyl-2,3-dihydroquinazolin-4(1H)-one [(±)-Retro-2cycl] as the chemical structure of Retro-2 that showed mouse protection against ricin, a notorious ribosome inactivating protein (RIP). Herein we report our chemical resolution of (±)-Retro-2cycl, analog synthesis, and cell-based evaluation showing that the two optically pure enantiomers and their achiral analog have nearly the same degree of cell protection against ricin as (±)-Retro-2cycl. We also report our computational studies explaining the lack of stereo preference and revealing a common pharmacophore of structurally distinct inhibitors of intracellular retrograde trafficking of RIPs. This pharmacophore comprises a central aromatic ring o-substituted by an aromatic ring and a moiety bearing an O or S atom attached to sp2 C atom(s). These results offer new insights into lead identification and optimization for RIP antidote development to minimize the global health threat caused by ribosome-inactivating proteins.
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A retrograde trafficking inhibitor of ricin and Shiga-like toxins inhibits infection of cells by human and monkey polyomaviruses. mBio 2013; 4:e00729-13. [PMID: 24222489 PMCID: PMC3892778 DOI: 10.1128/mbio.00729-13] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Polyomaviruses are ubiquitous pathogens that cause severe disease in immunocompromised individuals. JC polyomavirus (JCPyV) is the causative agent of the fatal demyelinating disease progressive multifocal leukoencephalopathy (PML), whereas BK polyomavirus (BKPyV) causes polyomavirus-induced nephropathy and hemorrhagic cystitis. Vaccines or antiviral therapies targeting these viruses do not exist, and treatments focus on reducing the underlying causes of immunosuppression. We demonstrate that retro-2(cycl), an inhibitor of ricin and Shiga-like toxins (SLTs), inhibits infection by JCPyV, BKPyV, and simian virus 40. Retro-2(cycl) inhibits retrograde transport of polyomaviruses to the endoplasmic reticulum, a step necessary for productive infection. Retro-2(cycl) likely inhibits polyomaviruses in a way similar to its ricin and SLT inhibition, suggesting an overlap in the cellular host factors used by bacterial toxins and polyomaviruses. This work establishes retro-2(cycl) as a potential antiviral therapy that broadly inhibits polyomaviruses and possibly other pathogens that use retrograde trafficking. IMPORTANCE The human polyomaviruses JC polyomavirus (JCPyV) and BK polyomavirus (BKPyV) cause rare but severe diseases in individuals with reduced immune function. During immunosuppression, JCPyV disseminates from the kidney to the central nervous system and destroys oligodendrocytes, resulting in the fatal disease progressive multifocal leukoencephalopathy. Kidney transplant recipients are at increased risk of BKPyV-induced nephropathy, which results in kidney necrosis and loss of the transplanted organ. There are currently no effective therapies for JCPyV and BKPyV. We show that a small molecule named retro-2(cycl) protects cells from infection with JCPyV and BKPyV by inhibiting intracellular viral transport. Retro-2(cycl) treatment reduces viral spreading in already established infections and may therefore be able to control infection in affected patients. Further optimization of retro-2(cycl) may result in the development of an effective antiviral therapy directed toward pathogens that use retrograde trafficking to infect their hosts.
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Sandvig K, Skotland T, van Deurs B, Klokk TI. Retrograde transport of protein toxins through the Golgi apparatus. Histochem Cell Biol 2013; 140:317-26. [PMID: 23765164 DOI: 10.1007/s00418-013-1111-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2013] [Indexed: 12/13/2022]
Abstract
A number of protein toxins from plants and bacteria take advantage of transport through the Golgi apparatus to gain entry into the cytosol where they exert their action. These toxins include the plant toxin ricin, the bacterial Shiga toxins, and cholera toxin. Such toxins bind to lipids or proteins at the cell surface, and they are endocytosed both by clathrin-dependent and clathrin-independent mechanisms. Sorting to the Golgi and retrograde transport to the endoplasmic reticulum (ER) are common to these toxins, but the exact mechanisms turn out to be toxin and cell-type dependent. In the ER, the enzymatically active part is released and then transported into the cytosol, exploiting components of the ER-associated degradation system. In this review, we will discuss transport of different protein toxins, but we will focus on factors involved in entry and sorting of ricin and Shiga toxin into and through the Golgi apparatus.
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Affiliation(s)
- Kirsten Sandvig
- Centre for Cancer Biomedicine, University of Oslo, Oslo, Norway.
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26
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Noel R, Gupta N, Pons V, Goudet A, Garcia-Castillo MD, Michau A, Martinez J, Buisson DA, Johannes L, Gillet D, Barbier J, Cintrat JC. N-Methyldihydroquinazolinone Derivatives of Retro-2 with Enhanced Efficacy against Shiga Toxin. J Med Chem 2013; 56:3404-13. [DOI: 10.1021/jm4002346] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Romain Noel
- CEA, iBiTec-S/SCBM, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Neetu Gupta
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Valérie Pons
- CEA, iBiTec-S/SCBM, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Amélie Goudet
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Maria Daniela Garcia-Castillo
- UMR144 CNRS and Traffic, Signaling,
and Delivery Laboratory, Institut Curie, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Aurélien Michau
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Jennifer Martinez
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | | | - Ludger Johannes
- UMR144 CNRS and Traffic, Signaling,
and Delivery Laboratory, Institut Curie, 26 Rue d’Ulm, 75248 Paris Cedex 05, France
| | - Daniel Gillet
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
| | - Julien Barbier
- CEA, iBiTec-S/SIMOPRO, CEA-Saclay, LabEx LERMIT, F-91191 Gif-sur-Yvette, France
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May KL, Yan Q, Tumer NE. Targeting ricin to the ribosome. Toxicon 2013; 69:143-51. [PMID: 23454625 DOI: 10.1016/j.toxicon.2013.02.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 02/01/2013] [Accepted: 02/06/2013] [Indexed: 12/15/2022]
Abstract
The plant toxin ricin is highly toxic for mammalian cells and is of concern for bioterrorism. Ricin belongs to a family of functionally related toxins, collectively referred to as ribosome inactivating proteins (RIPs), which disable ribosomes and halt protein synthesis. Currently there are no specific antidotes against ricin or related RIPs. The catalytic subunit of ricin is an N-glycosidase that depurinates a universally conserved adenine residue within the sarcin/ricin loop (SRL) of the 28S rRNA. This depurination activity inhibits translation and its biochemistry has been intensively studied. Yet, recent developments paint a more complex picture of toxicity, with ribosomal proteins and cellular signaling pathways contributing to the potency of ricin. In particular, several studies have now established the importance of the ribosomal stalk structure in facilitating the depurination activity and ribosome specificity of ricin and other RIPs. This review highlights recent developments defining toxin-ribosome interactions and examines the significance of these interactions for toxicity and therapeutic intervention.
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Affiliation(s)
- Kerrie L May
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, 59 Dudley Road, New Brunswick, NJ 08901-8520, USA
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28
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Wahome PG, Ahlawat S, Mantis NJ. Identification of small molecules that suppress ricin-induced stress-activated signaling pathways. PLoS One 2012; 7:e49075. [PMID: 23133670 PMCID: PMC3486792 DOI: 10.1371/journal.pone.0049075] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Accepted: 10/03/2012] [Indexed: 02/03/2023] Open
Abstract
Ricin is a member of the ribosome-inactivating protein (RIP) family of plant and bacterial toxins. In this study we used a high-throughput, cell-based assay to screen more than 118,000 compounds from diverse chemical libraries for molecules that reduced ricin-induced cell death. We describe three compounds, PW66, PW69, and PW72 that at micromolar concentrations significantly delayed ricin-induced cell death. None of the compounds had any demonstrable effect on ricin's ability to arrest protein synthesis in cells or on ricin's enzymatic activity as assessed in vitro. Instead, all three compounds appear to function by blocking downstream stress-induced signaling pathways associated with the toxin-mediated apoptosis. PW66 virtually eliminated ricin-induced TNF-α secretion by J774A.1 macrophages and concomitantly blocked activation of the p38 MAPK and JNK signaling pathways. PW72 suppressed ricin-induced TNF-α secretion, but not p38 MAPK and JNK signaling. PW69 suppressed activity of the executioner caspases 3/7 in ricin toxin- and Shiga toxin 2-treated cells. While the actual molecular targets of the three compounds have yet to be identified, these data nevertheless underscore the potential of small molecules to down-regulate inflammatory signaling pathways associated with exposure to the RIP family of toxins.
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Affiliation(s)
- Paul G. Wahome
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Sarita Ahlawat
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
| | - Nicholas J. Mantis
- Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, New York, United States of America
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, New York, United States of America
- * E-mail:
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