1
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Forth JH, Calvelage S, Fischer M, Hellert J, Sehl-Ewert J, Roszyk H, Deutschmann P, Reichold A, Lange M, Thulke HH, Sauter-Louis C, Höper D, Mandyhra S, Sapachova M, Beer M, Blome S. African swine fever virus - variants on the rise. Emerg Microbes Infect 2023; 12:2146537. [PMID: 36356059 PMCID: PMC9793911 DOI: 10.1080/22221751.2022.2146537] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
African swine fever virus (ASFV), a large and complex DNA-virus circulating between soft ticks and indigenous suids in sub-Saharan Africa, has made its way into swine populations from Europe to Asia. This virus, causing a severe haemorrhagic disease (African swine fever) with very high lethality rates in wild boar and domestic pigs, has demonstrated a remarkably high genetic stability for over 10 years. Consequently, analyses into virus evolution and molecular epidemiology often struggled to provide the genetic basis to trace outbreaks while few resources have been dedicated to genomic surveillance on whole-genome level. During its recent incursion into Germany in 2020, ASFV has unexpectedly diverged into five clearly distinguishable linages with at least ten different variants characterized by high-impact mutations never identified before. Noticeably, all new variants share a frameshift mutation in the 3' end of the DNA polymerase PolX gene O174L, suggesting a causative role as possible mutator gene. Although epidemiological modelling supported the influence of increased mutation rates, it remains unknown how fast virus evolution might progress under these circumstances. Moreover, a tailored Sanger sequencing approach allowed us, for the first time, to trace variants with genomic epidemiology to regional clusters. In conclusion, our findings suggest that this new factor has the potential to dramatically influence the course of the ASFV pandemic with unknown outcome. Therefore, our work highlights the importance of genomic surveillance of ASFV on whole-genome level, the need for high-quality sequences and calls for a closer monitoring of future phenotypic changes of ASFV.
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Affiliation(s)
- Jan H. Forth
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Sten Calvelage
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Melina Fischer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Jan Hellert
- Centre for Structural System Biology (CSSB), Leibnitz-Institut für Virologie, Hamburg, Germany
| | - Julia Sehl-Ewert
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Hanna Roszyk
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Paul Deutschmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Adam Reichold
- Department of Ecological Modelling, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Martin Lange
- Department of Ecological Modelling, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | - Hans-Hermann Thulke
- Department of Ecological Modelling, Helmholtz Centre for Environmental Research, Leipzig, Germany
| | | | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Svitlana Mandyhra
- State Scientific and Research Institute of Laboratory Diagnostics and Veterinary and Sanitary Expertise (SSRILDVSE), Kiev, Ukraine
| | - Maryna Sapachova
- State Scientific and Research Institute of Laboratory Diagnostics and Veterinary and Sanitary Expertise (SSRILDVSE), Kiev, Ukraine
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Sandra Blome
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald, Germany, Sandra Blome Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Suedufer 10, 17493, Greifswald – Insel Riems, Germany
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2
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Hover S, Charlton FW, Hellert J, Swanson JJ, Mankouri J, Barr JN, Fontana J. Organisation of the orthobunyavirus tripodal spike and the structural changes induced by low pH and K + during entry. Nat Commun 2023; 14:5885. [PMID: 37735161 PMCID: PMC10514341 DOI: 10.1038/s41467-023-41205-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 08/26/2023] [Indexed: 09/23/2023] Open
Abstract
Following endocytosis, enveloped viruses employ the changing environment of maturing endosomes as cues to promote endosomal escape, a process often mediated by viral glycoproteins. We previously showed that both high [K+] and low pH promote entry of Bunyamwera virus (BUNV), the prototypical bunyavirus. Here, we use sub-tomogram averaging and AlphaFold, to generate a pseudo-atomic model of the whole BUNV glycoprotein envelope. We unambiguously locate the Gc fusion domain and its chaperone Gn within the floor domain of the spike. Furthermore, viral incubation at low pH and high [K+], reminiscent of endocytic conditions, results in a dramatic rearrangement of the BUNV envelope. Structural and biochemical assays indicate that pH 6.3/K+ in the absence of a target membrane elicits a fusion-capable triggered intermediate state of BUNV GPs; but the same conditions induce fusion when target membranes are present. Taken together, we provide mechanistic understanding of the requirements for bunyavirus entry.
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Affiliation(s)
- Samantha Hover
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom
| | - Frank W Charlton
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom
| | - Jan Hellert
- Centre for Structural Systems Biology, Leibniz-Institut für Virologie (LIV), Notkestraße 85, 22607, Hamburg, Germany
| | - Jessica J Swanson
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom
| | - Jamel Mankouri
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom.
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom.
| | - John N Barr
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom.
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom.
| | - Juan Fontana
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, Leeds, United Kingdom.
- Astbury Centre for Structural and Molecular Biology, University of Leeds, LS2 9JT, Leeds, United Kingdom.
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3
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Hellert J, Aebischer A, Haouz A, Guardado-Calvo P, Reiche S, Beer M, Rey FA. Structure, function, and evolution of the Orthobunyavirus membrane fusion glycoprotein. Cell Rep 2023; 42:112142. [PMID: 36827185 DOI: 10.1016/j.celrep.2023.112142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 12/29/2022] [Accepted: 02/07/2023] [Indexed: 02/24/2023] Open
Abstract
La Crosse virus, responsible for pediatric encephalitis in the United States, and Schmallenberg virus, a highly teratogenic veterinary virus in Europe, belong to the large Orthobunyavirus genus of zoonotic arthropod-borne pathogens distributed worldwide. Viruses in this under-studied genus cause CNS infections or fever with debilitating arthralgia/myalgia syndromes, with no effective treatment. The main surface antigen, glycoprotein Gc (∼1,000 residues), has a variable N-terminal half (GcS) targeted by the patients' antibody response and a conserved C-terminal moiety (GcF) responsible for membrane fusion during cell entry. Here, we report the X-ray structure of post-fusion La Crosse and Schmallenberg virus GcF, revealing the molecular determinants for hairpin formation and trimerization required to drive membrane fusion. We further experimentally confirm the role of residues in the fusion loops and in a vestigial endoplasmic reticulum (ER) translocation sequence at the GcS-GcF junction. The resulting knowledge provides essential molecular underpinnings for future development of potential therapeutic treatments and vaccines.
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Affiliation(s)
- Jan Hellert
- Structural Virology Unit, Institut Pasteur - Université Paris-Cité, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015 Paris, France; Centre for Structural Systems Biology (CSSB), Leibniz-Institut für Virologie (LIV), Notkestraße 85, 22607 Hamburg, Germany
| | - Andrea Aebischer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Germany; Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Germany
| | - Ahmed Haouz
- Crystallography Platform C2RT, Institut Pasteur, CNRS UMR 3528, 25-28 rue du Dr. Roux, 75015 Paris, France
| | - Pablo Guardado-Calvo
- Structural Virology Unit, Institut Pasteur - Université Paris-Cité, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015 Paris, France
| | - Sven Reiche
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Germany
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493 Greifswald, Germany.
| | - Félix A Rey
- Structural Virology Unit, Institut Pasteur - Université Paris-Cité, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015 Paris, France.
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4
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de Melo GD, Hellert J, Gupta R, Corti D, Bourhy H. Monoclonal antibodies against rabies: current uses in prophylaxis and in therapy. Curr Opin Virol 2022; 53:101204. [PMID: 35151116 DOI: 10.1016/j.coviro.2022.101204] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 01/11/2022] [Accepted: 01/15/2022] [Indexed: 12/25/2022]
Abstract
Rabies is a severe viral infection that causes an acute encephalomyelitis, which presents a case fatality of nearly 100% after the manifestation of neurological clinical signs. Rabies can be efficiently prevented with post-exposure prophylaxis (PEP), composed of vaccines and anti-rabies immunoglobulins (RIGs); however, no treatment exists for symptomatic rabies. The PEP protocol faces access and implementation obstacles in resource-limited settings, which could be partially overcome by substituting RIGs for monoclonal antibodies (mAbs). mAbs offer lower production costs, consistent supply availability, long-term storage/stability, and an improved safety profile. Here we summarize the key features of the different available mAbs against rabies, focusing on their application in PEP and highlighting their potential in a novel therapeutic approach.
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Affiliation(s)
- Guilherme Dias de Melo
- Institut Pasteur, Université de Paris, Lyssavirus Epidemiology and Neuropathology Unit, Paris, F-75015, France
| | - Jan Hellert
- Centre for Structural Systems Biology, Leibniz-Institut für Experimentelle Virologie (HPI), Notkestrasse 85, Hamburg, 22607, Germany
| | | | - Davide Corti
- Humabs Biomed SA, a Subsidiary of Vir Biotechnology, Bellinzona, Switzerland
| | - Hervé Bourhy
- Institut Pasteur, Université de Paris, Lyssavirus Epidemiology and Neuropathology Unit, Paris, F-75015, France; Institut Pasteur, Université de Paris, National Reference Center for Rabies, Paris, F-75015, France; Institut Pasteur, Université de Paris, WHO Collaborating Centre for Reference and Research on Rabies, Paris, F-75015, France.
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5
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Mishra AK, Hellert J, Freitas N, Guardado-Calvo P, Haouz A, Fels JM, Maurer DP, Abelson DM, Bornholdt ZA, Walker LM, Chandran K, Cosset FL, McLellan JS, Rey FA. Structural basis of synergistic neutralization of Crimean-Congo hemorrhagic fever virus by human antibodies. Science 2022; 375:104-109. [PMID: 34793197 PMCID: PMC9771711 DOI: 10.1126/science.abl6502] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is the most widespread tick-borne zoonotic virus, with a 30% case fatality rate in humans. Structural information is lacking in regard to the CCHFV membrane fusion glycoprotein Gc—the main target of the host neutralizing antibody response—as well as antibody–mediated neutralization mechanisms. We describe the structure of prefusion Gc bound to the antigen-binding fragments (Fabs) of two neutralizing antibodies that display synergy when combined, as well as the structure of trimeric, postfusion Gc. The structures show the two Fabs acting in concert to block membrane fusion, with one targeting the fusion loops and the other blocking Gc trimer formation. The structures also revealed the neutralization mechanism of previously reported antibodies against CCHFV, providing the molecular underpinnings essential for developing CCHFV–specific medical countermeasures for epidemic preparedness.
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Affiliation(s)
- Akaash K. Mishra
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, USA 78712
| | - Jan Hellert
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, Paris, France 75724
| | - Natalia Freitas
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, 46 allée d’Italie, Lyon, France 69007
| | - Pablo Guardado-Calvo
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, Paris, France 75724
| | - Ahmed Haouz
- Crystallography Platform C2RT, Institut Pasteur, CNRS UMR 3528, 25-28 rue du Docteur Roux, Cedex 15, Paris, France 75724
| | - J. Maximilian Fels
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA 10461
| | | | | | | | | | - Kartik Chandran
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA 10461
| | - François-Loïc Cosset
- CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, 46 allée d’Italie, Lyon, France 69007
| | - Jason S. McLellan
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, USA 78712,Correspondence: (J.S.M.); (F.A.R)
| | - Felix A. Rey
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, Paris, France 75724,Correspondence: (J.S.M.); (F.A.R)
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6
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Pérot P, Bielle F, Bigot T, Foulongne V, Bolloré K, Chrétien D, Gil P, Gutiérrez S, L'Ambert G, Mokhtari K, Hellert J, Flamand M, Tamietti C, Coulpier M, Huard de Verneuil A, Temmam S, Couderc T, De Sousa Cunha E, Boluda S, Plu I, Delisle MB, Bonneville F, Brassat D, Fieschi C, Malphettes M, Duyckaerts C, Mathon B, Demeret S, Seilhean D, Eloit M. Identification of Umbre Orthobunyavirus as a Novel Zoonotic Virus Responsible for Lethal Encephalitis in 2 French Patients with Hypogammaglobulinemia. Clin Infect Dis 2021; 72:1701-1708. [PMID: 32516409 DOI: 10.1093/cid/ciaa308] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/18/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Human encephalitis represents a medical challenge from a diagnostic and therapeutic point of view. We investigated the cause of 2 fatal cases of encephalitis of unknown origin in immunocompromised patients. METHODS Untargeted metatranscriptomics was applied on the brain tissue of 2 patients to search for pathogens (viruses, bacteria, fungi, or protozoans) without a prior hypothesis. RESULTS Umbre arbovirus, an orthobunyavirus never previously identified in humans, was found in 2 patients. In situ hybridization and reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) showed that Umbre virus infected neurons and replicated at high titers. The virus was not detected in cerebrospinal fluid by RT-qPCR. Viral sequences related to Koongol virus, another orthobunyavirus close to Umbre virus, were found in Culex pipiens mosquitoes captured in the south of France where the patients had spent some time before the onset of symptoms, demonstrating the presence of the same clade of arboviruses in Europe and their potential public health impact. A serological survey conducted in the same area did not identify individuals positive for Umbre virus. The absence of seropositivity in the population may not reflect the actual risk of disease transmission in immunocompromised individuals. CONCLUSIONS Umbre arbovirus can cause encephalitis in immunocompromised humans and is present in Europe.
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Affiliation(s)
- Philippe Pérot
- Pathogen Discovery Laboratory, Institut Pasteur, Paris, France
| | - Franck Bielle
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France
| | - Thomas Bigot
- Hub de Bioinformatique et Biostatistique - Département Biologie Computationnelle, Institut Pasteur, Unité de Service et de Recherche 3756 CNRS, Paris, France
| | - Vincent Foulongne
- Pathogenesis and Control of Chronic Infections, INSERM, University of Montpellier, Etablissement Français du Sang, Centre Hospitalier Universitaire (CHU) Montpellier, Montpellier, France
| | - Karine Bolloré
- Pathogenesis and Control of Chronic Infections, INSERM, University of Montpellier, Etablissement Français du Sang, Centre Hospitalier Universitaire (CHU) Montpellier, Montpellier, France
| | | | - Patricia Gil
- Centre de Coopération Internationale en Recherche Agronomique Pour le Développement (CIRAD), UMR ASTRE, Montpellier, France.,ASTRE, CIRAD, Institut National de la Recherche Agronomique, University of Montpellier, Montpellier, France
| | - Serafín Gutiérrez
- Centre de Coopération Internationale en Recherche Agronomique Pour le Développement (CIRAD), UMR ASTRE, Montpellier, France.,ASTRE, CIRAD, Institut National de la Recherche Agronomique, University of Montpellier, Montpellier, France
| | - Grégory L'Ambert
- Entente Interdépartementale Pour la Démoustication Méditerranée, Montpellier, France
| | - Karima Mokhtari
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France
| | - Jan Hellert
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
| | - Marie Flamand
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
| | - Carole Tamietti
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
| | - Muriel Coulpier
- UMR Virologie, Agence Nationale de Sécurité Sanitaire de l'Alimentation, de l'Environnement et du Travail, École Nationale Vétérinaire d'Alfort, Institut National de Recherche Pour l'Agriculture, l'Alimentation et l'Environnement, Université Paris Est, Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort, France
| | - Anne Huard de Verneuil
- UMR Virologie, Agence Nationale de Sécurité Sanitaire de l'Alimentation, de l'Environnement et du Travail, École Nationale Vétérinaire d'Alfort, Institut National de Recherche Pour l'Agriculture, l'Alimentation et l'Environnement, Université Paris Est, Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort, France
| | - Sarah Temmam
- Pathogen Discovery Laboratory, Institut Pasteur, Paris, France
| | - Thérèse Couderc
- Biology of Infection Unit, Institut Pasteur, INSERM U1117, Paris, France
| | - Edouard De Sousa Cunha
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - Susana Boluda
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France.,Centre National de Référence des Agents Transmissibles Non Conventionnels (Reference Center for Nonconventional Transmissible Agents), Laboratory and Neuropathology Network for the Surveillance of Creutzfeldt-Jakob Disease, Santé Publique France, AP-HP, Paris, France
| | - Isabelle Plu
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France.,Centre National de Référence des Agents Transmissibles Non Conventionnels (Reference Center for Nonconventional Transmissible Agents), Laboratory and Neuropathology Network for the Surveillance of Creutzfeldt-Jakob Disease, Santé Publique France, AP-HP, Paris, France
| | - Marie Bernadette Delisle
- Laboratoire de Neuropathologie, Laboratoire Universitaire d'Anatomie et Cytologie Pathologiques, CHU de Toulouse, Université Toulouse III-Paul Sabatier, Toulouse, France
| | - Fabrice Bonneville
- Department of Neuroradiology, CHU de Toulouse and UMR 1214 Toulouse NeuroImaging Center, Université de Toulouse, INSERM, Toulouse, France
| | - David Brassat
- Centre de Ressources et de Compétences Sclérose en Plaques, Pole des Neurosciences CHU Toulouse and UMR 1043, Université de Toulouse III, Toulouse, France
| | - Claire Fieschi
- Service d'Immunologie Clinique, Hôpital Saint-Louis, Assistance Publique-Hôpitaux de Paris, Université de Paris, Paris, France
| | - Marion Malphettes
- Service d'Immunologie Clinique, Hôpital Saint-Louis, Assistance Publique-Hôpitaux de Paris, Université de Paris, Paris, France
| | - Charles Duyckaerts
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France
| | - Bertrand Mathon
- Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France.,AP-HP, Hôpitaux Universitaires Pitié-Salpêtrière Charles-Foix, Department of Neurosurgery, Paris, France
| | - Sophie Demeret
- Department of Neurology, Neuro ICU, Groupe Hospitalier Pitié-Salpêtrière, AP-HP, Paris, France
| | - Danielle Seilhean
- Département de Neuropathologie Raymond Escourolle, Assistance Publique - Hôpitaux de Paris (AP-HP)-Sorbonne, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,Sorbonne Université, Brain Institute (Institut du Cerveau et de la Moelle épinière; Institut National de la Santé et de la Recherche Médicale [INSERM], Unité Mixte de Recherche Santé 1127; Centre National de la Recherche Scientifique [CNRS], Unité Mixte de Recherche [UMR] 7225), Paris, France.,Centre National de Référence des Agents Transmissibles Non Conventionnels (Reference Center for Nonconventional Transmissible Agents), Laboratory and Neuropathology Network for the Surveillance of Creutzfeldt-Jakob Disease, Santé Publique France, AP-HP, Paris, France
| | - Marc Eloit
- Pathogen Discovery Laboratory, Institut Pasteur, Paris, France.,Ecole Nationale Vétérinaire d'Alfort, Maisons-Alfort, France
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7
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Fels JM, Maurer DP, Herbert AS, Wirchnianski AS, Vergnolle O, Cross RW, Abelson DM, Moyer CL, Mishra AK, Aguilan JT, Kuehne AI, Pauli NT, Bakken RR, Nyakatura EK, Hellert J, Quevedo G, Lobel L, Balinandi S, Lutwama JJ, Zeitlin L, Geisbert TW, Rey FA, Sidoli S, McLellan JS, Lai JR, Bornholdt ZA, Dye JM, Walker LM, Chandran K. Protective neutralizing antibodies from human survivors of Crimean-Congo hemorrhagic fever. Cell 2021; 184:3486-3501.e21. [PMID: 34077751 DOI: 10.1016/j.cell.2021.05.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/19/2021] [Accepted: 04/29/2021] [Indexed: 12/31/2022]
Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV) is a World Health Organization priority pathogen. CCHFV infections cause a highly lethal hemorrhagic fever for which specific treatments and vaccines are urgently needed. Here, we characterize the human immune response to natural CCHFV infection to identify potent neutralizing monoclonal antibodies (nAbs) targeting the viral glycoprotein. Competition experiments showed that these nAbs bind six distinct antigenic sites in the Gc subunit. These sites were further delineated through mutagenesis and mapped onto a prefusion model of Gc. Pairwise screening identified combinations of non-competing nAbs that afford synergistic neutralization. Further enhancements in neutralization breadth and potency were attained by physically linking variable domains of synergistic nAb pairs through bispecific antibody (bsAb) engineering. Although multiple nAbs protected mice from lethal CCHFV challenge in pre- or post-exposure prophylactic settings, only a single bsAb, DVD-121-801, afforded therapeutic protection. DVD-121-801 is a promising candidate suitable for clinical development as a CCHFV therapeutic.
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Affiliation(s)
- J Maximilian Fels
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | | | - Andrew S Herbert
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA; The Geneva Foundation, Tacoma, WA 98402, USA
| | - Ariel S Wirchnianski
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA; Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Olivia Vergnolle
- Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Robert W Cross
- Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77550, USA; Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77550, USA
| | | | | | - Akaash K Mishra
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Jennifer T Aguilan
- Department of Pathology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ana I Kuehne
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
| | | | - Russell R Bakken
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
| | - Elisabeth K Nyakatura
- Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jan Hellert
- Structural Virology Unit, Department of Virology, CNRS UMR 3569, Institut Pasteur, Paris 75724, France
| | - Gregory Quevedo
- Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Leslie Lobel
- Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
| | | | | | - Larry Zeitlin
- Mapp Biopharmaceutical, Inc., San Diego, CA 92121, USA
| | - Thomas W Geisbert
- Galveston National Laboratory, University of Texas Medical Branch, Galveston, TX 77550, USA; Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Felix A Rey
- Structural Virology Unit, Department of Virology, CNRS UMR 3569, Institut Pasteur, Paris 75724, France
| | - Simone Sidoli
- Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jason S McLellan
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Jonathan R Lai
- Deparment of Biochemistry, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | | | - John M Dye
- U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA.
| | - Laura M Walker
- Adimab, LLC, Lebanon, NH 03766, USA; Adagio Therapeutics, Inc., Waltham, MA 02451, USA.
| | - Kartik Chandran
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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8
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Wichgers Schreur PJ, van de Water S, Harmsen M, Bermúdez-Méndez E, Drabek D, Grosveld F, Wernike K, Beer M, Aebischer A, Daramola O, Rodriguez Conde S, Brennan K, Kozub D, Søndergaard Kristiansen M, Mistry KK, Deng Z, Hellert J, Guardado-Calvo P, Rey FA, van Keulen L, Kortekaas J. Multimeric single-domain antibody complexes protect against bunyavirus infections. eLife 2020; 9:52716. [PMID: 32314955 PMCID: PMC7173960 DOI: 10.7554/elife.52716] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 04/11/2020] [Indexed: 12/25/2022] Open
Abstract
The World Health Organization has included three bunyaviruses posing an increasing threat to human health on the Blueprint list of viruses likely to cause major epidemics and for which no, or insufficient countermeasures exist. Here, we describe a broadly applicable strategy, based on llama-derived single-domain antibodies (VHHs), for the development of bunyavirus biotherapeutics. The method was validated using the zoonotic Rift Valley fever virus (RVFV) and Schmallenberg virus (SBV), an emerging pathogen of ruminants, as model pathogens. VHH building blocks were assembled into highly potent neutralizing complexes using bacterial superglue technology. The multimeric complexes were shown to reduce and prevent virus-induced morbidity and mortality in mice upon prophylactic administration. Bispecific molecules engineered to present two different VHHs fused to an Fc domain were further shown to be effective upon therapeutic administration. The presented VHH-based technology holds great promise for the development of bunyavirus antiviral therapies.
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Affiliation(s)
| | - Sandra van de Water
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Michiel Harmsen
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Erick Bermúdez-Méndez
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands.,Laboratory of Virology, Wageningen University, Wageningen, Netherlands
| | - Dubravka Drabek
- Department of Cell Biology, Erasmus MC, Rotterdam, Netherlands.,Harbour Antibodies B.V, Rotterdam, Netherlands
| | - Frank Grosveld
- Department of Cell Biology, Erasmus MC, Rotterdam, Netherlands.,Harbour Antibodies B.V, Rotterdam, Netherlands
| | - Kerstin Wernike
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - Andrea Aebischer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald - Insel Riems, Germany
| | - Olalekan Daramola
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | - Sara Rodriguez Conde
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | - Karen Brennan
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | - Dorota Kozub
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | | | - Kieran K Mistry
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | - Ziyan Deng
- Biopharmaceutical Development, R&D BioPharmaceuticals, AstraZeneca, Cambridge, United Kingdom
| | - Jan Hellert
- Structural Virology Unit, Virology Department, CNRS UMR 3569, Institut Pasteur, Paris, France
| | - Pablo Guardado-Calvo
- Structural Virology Unit, Virology Department, CNRS UMR 3569, Institut Pasteur, Paris, France
| | - Félix A Rey
- Structural Virology Unit, Virology Department, CNRS UMR 3569, Institut Pasteur, Paris, France
| | - Lucien van Keulen
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands
| | - Jeroen Kortekaas
- Department of Virology, Wageningen Bioveterinary Research, Lelystad, Netherlands.,Laboratory of Virology, Wageningen University, Wageningen, Netherlands
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9
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Hellert J, Buchrieser J, Larrous F, Minola A, de Melo GD, Soriaga L, England P, Haouz A, Telenti A, Schwartz O, Corti D, Bourhy H, Rey FA. Structure of the prefusion-locking broadly neutralizing antibody RVC20 bound to the rabies virus glycoprotein. Nat Commun 2020; 11:596. [PMID: 32001700 PMCID: PMC6992781 DOI: 10.1038/s41467-020-14398-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/02/2020] [Indexed: 10/25/2022] Open
Abstract
Rabies virus (RABV) causes fatal encephalitis in more than 59,000 people yearly. Upon the bite of an infected animal, the development of clinical disease can be prevented with post-exposure prophylaxis (PEP), which includes the administration of Rabies immunoglobulin (RIG). However, the high cost and limited availability of serum-derived RIG severely hamper its wide use in resource-limited countries. A safe low-cost alternative is provided by using broadly neutralizing monoclonal antibodies (bnAbs). Here we report the X-ray structure of one of the most potent and most broadly reactive human bnAbs, RVC20, in complex with its target domain III of the RABV glycoprotein (G). The structure reveals that the RVC20 binding determinants reside in a highly conserved surface of G, rationalizing its broad reactivity. We further show that RVC20 blocks the acid-induced conformational change required for membrane fusion. Our results may guide the future development of direct antiviral small molecules for Rabies treatment.
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Affiliation(s)
- Jan Hellert
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Julian Buchrieser
- Virus and Immunity Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Florence Larrous
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Andrea Minola
- Humabs BioMed SA, a subsidiary of Vir Biotechnology Inc., Via dei Gaggini 3, 6500, Bellinzona, Switzerland
| | - Guilherme Dias de Melo
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Leah Soriaga
- Vir Biotechnology Inc, San Francisco, CA, 94158, USA
| | - Patrick England
- Molecular Biophysics Platform C2RT, Institut Pasteur, CNRS UMR 3528, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Ahmed Haouz
- Crystallography Platform C2RT, Institut Pasteur, CNRS UMR 3528, 25-28 rue du Dr. Roux, Cedex 15, 75724, Paris, France
| | | | - Olivier Schwartz
- Virus and Immunity Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France
| | - Davide Corti
- Humabs BioMed SA, a subsidiary of Vir Biotechnology Inc., Via dei Gaggini 3, 6500, Bellinzona, Switzerland
| | - Hervé Bourhy
- Lyssavirus Epidemiology and Neuropathology Unit, Institut Pasteur, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France.
| | - Félix A Rey
- Structural Virology Unit, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Docteur Roux, Cedex 15, 75724, Paris, France.
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10
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Hellert J, Aebischer A, Wernike K, Haouz A, Brocchi E, Reiche S, Guardado-Calvo P, Beer M, Rey FA. Orthobunyavirus spike architecture and recognition by neutralizing antibodies. Nat Commun 2019; 10:879. [PMID: 30787296 PMCID: PMC6382863 DOI: 10.1038/s41467-019-08832-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 01/29/2019] [Indexed: 12/29/2022] Open
Abstract
Orthobunyaviruses (OBVs) form a distinct genus of arthropod-borne bunyaviruses that can cause severe disease upon zoonotic transmission to humans. Antigenic drift or genome segment re-assortment have in the past resulted in new pathogenic OBVs, making them potential candidates for causing emerging zoonoses in the future. Low-resolution electron cryo-tomography studies have shown that OBV particles feature prominent trimeric spikes, but their molecular organization remained unknown. Here we report X-ray crystallography studies of four different OBVs showing that the spikes are formed by an N-terminal extension of the fusion glycoprotein Gc. Using Schmallenberg virus, a recently emerged OBV, we also show that the projecting spike is the major target of the neutralizing antibody response, and provide X-ray structures in complex with two protecting antibodies. We further show that immunization of mice with the spike domains elicits virtually sterilizing immunity, providing fundamental knowledge essential in the preparation for potential newly emerging OBV zoonoses. Orthobunyaviruses (OBVs) cause severe disease in humans and farm animals, but the molecular basis for infection is not fully understood. Here, the authors present crystal structures of free and antibody-bound OBV envelope glycoproteins and show that their domains enable efficient immunization in a mouse model.
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Affiliation(s)
- Jan Hellert
- Structural Virology Unit, Virology Department, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015, Paris, France
| | - Andrea Aebischer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald, Insel Riems, Germany
| | - Kerstin Wernike
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald, Insel Riems, Germany
| | - Ahmed Haouz
- Crystallography Platform, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR 3528, 25-28 rue du Dr. Roux, 75015, Paris, France
| | - Emiliana Brocchi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via Bianchi 7, 25125, Brescia, Italy
| | - Sven Reiche
- Department of Experimental Animal Facilities and Biorisk Management, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald, Insel Riems, Germany
| | - Pablo Guardado-Calvo
- Structural Virology Unit, Virology Department, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015, Paris, France
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald, Insel Riems, Germany.
| | - Félix A Rey
- Structural Virology Unit, Virology Department, Institut Pasteur, CNRS UMR 3569, 25-28 rue du Dr. Roux, 75015, Paris, France.
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11
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Hellert J, Krausze J, Schulz TF, Lührs T. Crystallization, room-temperature X-ray diffraction and preliminary analysis of Kaposi's sarcoma herpesvirus LANA bound to DNA. Acta Crystallogr F Struct Biol Commun 2014; 70:1570-4. [PMID: 25372834 DOI: 10.1107/s2053230x14019906] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 09/03/2014] [Indexed: 01/03/2023]
Abstract
The latency-associated nuclear antigen (LANA) is the latent origin-binding protein and chromatin anchor of the Kaposi's sarcoma herpesvirus (KSHV/HHV-8) genome. Its C-terminal domain (CTD) binds sequence-specifically to the viral origin of replication, whereas the N-terminal domain links it to nucleosomes of cellular chromatin for long-term persistence in dividing host cells. Here, the crystallization and X-ray data acquisition of a mutant LANA CTD in complex with its wild-type target DNA LBS1 is described. This report describes the rational protein engineering for successful co-crystallization with DNA and X-ray diffraction data collection at room temperature on the high-brilliance third-generation synchrotron PETRA III at DESY, Germany.
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Affiliation(s)
- Jan Hellert
- Department of Structural Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Joern Krausze
- Department of Structural Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Thomas F Schulz
- Institute of Virology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
| | - Thorsten Lührs
- Department of Structural Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
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12
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Lisson R, Hellert J, Ringleb M, Machens F, Kraus J, Hehl R. Alternative splicing of the maize Ac transposase transcript in transgenic sugar beet (Beta vulgaris L.). Plant Mol Biol 2010; 74:19-32. [PMID: 20512402 PMCID: PMC2921059 DOI: 10.1007/s11103-010-9651-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 05/10/2010] [Indexed: 05/29/2023]
Abstract
The maize Activator/Dissociation (Ac/Ds) transposable element system was introduced into sugar beet. The autonomous Ac and non-autonomous Ds element excise from the T-DNA vector and integrate at novel positions in the sugar beet genome. Ac and Ds excisions generate footprints in the donor T-DNA that support the hairpin model for transposon excision. Two complete integration events into genomic sugar beet DNA were obtained by IPCR. Integration of Ac leads to an eight bp duplication, while integration of Ds in a homologue of a sugar beet flowering locus gene did not induce a duplication. The molecular structure of the target site indicates Ds integration into a double strand break. Analyses of transposase transcription using RT-PCR revealed low amounts of alternatively spliced mRNAs. The fourth intron of the transposase was found to be partially misspliced. Four different splice products were identified. In addition, the second and third exon were found to harbour two and three novel introns, respectively. These utilize each the same splice donor but several alternative splice acceptor sites. Using the SplicePredictor online tool, one of the two introns within exon two is predicted to be efficiently spliced in maize. Most interestingly, splicing of this intron together with the four major introns of Ac would generate a transposase that lacks the DNA binding domain and two of its three nuclear localization signals, but still harbours the dimerization domain.
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Affiliation(s)
- Ralph Lisson
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
| | - Jan Hellert
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
| | - Malte Ringleb
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
| | - Fabian Machens
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
| | - Josef Kraus
- PLANTA GmbH, Grimsehlstr. 31, 37555 Einbeck, Germany
| | - Reinhard Hehl
- Institut für Genetik, Technische Universität Braunschweig, Spielmannstr. 7, 38106 Braunschweig, Germany
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