1
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Whitehead JD, Decool H, Leyrat C, Carrique L, Fix J, Eléouët JF, Galloux M, Renner M. Structure of the N-RNA/P interface indicates mode of L/P recruitment to the nucleocapsid of human metapneumovirus. Nat Commun 2023; 14:7627. [PMID: 37993464 PMCID: PMC10665349 DOI: 10.1038/s41467-023-43434-5] [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: 06/29/2023] [Accepted: 11/08/2023] [Indexed: 11/24/2023] Open
Abstract
Human metapneumovirus (HMPV) is a major cause of respiratory illness in young children. The HMPV polymerase (L) binds an obligate cofactor, the phosphoprotein (P). During replication and transcription, the L/P complex traverses the viral RNA genome, which is encapsidated within nucleoproteins (N). An essential interaction between N and a C-terminal region of P tethers the L/P polymerase to the template. This N-P interaction is also involved in the formation of cytoplasmic viral factories in infected cells, called inclusion bodies. To define how the polymerase component P recognizes N-encapsidated RNA (N-RNA) we employed cryogenic electron microscopy (cryo-EM) and molecular dynamics simulations, coupled to activity assays and imaging of inclusion bodies in cells. We report a 2.9 Å resolution structure of a triple-complex between multimeric N, bound to both RNA and the C-terminal region of P. Furthermore, we also present cryo-EM structures of assembled N in different oligomeric states, highlighting the plasticity of N. Combined with our functional assays, these structural data delineate in molecular detail how P attaches to N-RNA whilst retaining substantial conformational dynamics. Moreover, the N-RNA-P triple complex structure provides a molecular blueprint for the design of therapeutics to potentially disrupt the attachment of L/P to its template.
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Affiliation(s)
- Jack D Whitehead
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
| | - Hortense Decool
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | - Cédric Leyrat
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Loic Carrique
- Division of Structural Biology, The Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Jenna Fix
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France
| | | | - Marie Galloux
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78350, Jouy-en-Josas, France.
| | - Max Renner
- Department of Chemistry, Umeå University, Umeå, Sweden.
- Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden.
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2
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Diot C, Richard CA, Risso-Ballester J, Martin D, Fix J, Eléouët JF, Sizun C, Rameix-Welti MA, Galloux M. Hardening of Respiratory Syncytial Virus Inclusion Bodies by Cyclopamine Proceeds through Perturbation of the Interactions of the M2-1 Protein with RNA and the P Protein. Int J Mol Sci 2023; 24:13862. [PMID: 37762166 PMCID: PMC10531356 DOI: 10.3390/ijms241813862] [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: 06/24/2023] [Revised: 08/20/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Respiratory syncytial virus (RSV) RNA synthesis takes place in cytoplasmic viral factories also called inclusion bodies (IBs), which are membrane-less organelles concentrating the viral RNA polymerase complex. The assembly of IBs is driven by liquid-liquid phase separation promoted by interactions between the viral nucleoprotein N and the phosphoprotein P. We recently demonstrated that cyclopamine (CPM) inhibits RSV multiplication by disorganizing and hardening IBs. Although a single mutation in the viral transcription factor M2-1 induced resistance to CPM, the mechanism of action of CPM still remains to be characterized. Here, using FRAP experiments on reconstituted pseudo-IBs both in cellula and in vitro, we first demonstrated that CPM activity depends on the presence of M2-1 together with N and P. We showed that CPM impairs the competition between P and RNA binding to M2-1. As mutations on both P and M2-1 induced resistance against CPM activity, we suggest that CPM may affect the dynamics of the M2-1-P interaction, thereby affecting the relative mobility of the proteins contained in RSV IBs. Overall, our results reveal that stabilizing viral protein-protein interactions is an attractive new antiviral approach. They pave the way for the rational chemical optimization of new specific anti-RSV molecules.
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Affiliation(s)
- Cédric Diot
- Institut Pasteur, Université Paris Cité, M3P, F-75015 Paris, France;
- INSERM, UMR 1173 (2I), Université Paris-Saclay-Versailles St. Quentin, M3P, F-78180 Versailles, France;
| | - Charles-Adrien Richard
- INRAE, Unité de Virologie et Immunologie Moléculaires (VIM), Université Paris-Saclay-Versailles St. Quentin, F-78350 Jouy-en-Josas, France; (C.-A.R.); (D.M.); (J.F.); (J.-F.E.)
| | - Jennifer Risso-Ballester
- INSERM, UMR 1173 (2I), Université Paris-Saclay-Versailles St. Quentin, M3P, F-78180 Versailles, France;
| | - Davy Martin
- INRAE, Unité de Virologie et Immunologie Moléculaires (VIM), Université Paris-Saclay-Versailles St. Quentin, F-78350 Jouy-en-Josas, France; (C.-A.R.); (D.M.); (J.F.); (J.-F.E.)
| | - Jenna Fix
- INRAE, Unité de Virologie et Immunologie Moléculaires (VIM), Université Paris-Saclay-Versailles St. Quentin, F-78350 Jouy-en-Josas, France; (C.-A.R.); (D.M.); (J.F.); (J.-F.E.)
| | - Jean-François Eléouët
- INRAE, Unité de Virologie et Immunologie Moléculaires (VIM), Université Paris-Saclay-Versailles St. Quentin, F-78350 Jouy-en-Josas, France; (C.-A.R.); (D.M.); (J.F.); (J.-F.E.)
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, F-91190 Gif-sur-Yvette, France;
| | - Marie-Anne Rameix-Welti
- INSERM, UMR 1173 (2I), Université Paris-Saclay-Versailles St. Quentin, M3P, F-78180 Versailles, France;
- Laboratoire de Microbiologie, Hôpital Ambroise Paré, Assistance Publique des Hôpitaux de Paris, DMU15, F-75015 Paris, France
| | - Marie Galloux
- INRAE, Unité de Virologie et Immunologie Moléculaires (VIM), Université Paris-Saclay-Versailles St. Quentin, F-78350 Jouy-en-Josas, France; (C.-A.R.); (D.M.); (J.F.); (J.-F.E.)
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3
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Salgueiro M, Camporeale G, Visentin A, Aran M, Pellizza L, Esperante SA, Corbat A, Grecco H, Sousa B, Esperón R, Borkosky SS, de Prat-Gay G. Molten Globule Driven and Self-downmodulated Phase Separation of a Viral Factory Scaffold. J Mol Biol 2023; 435:168153. [PMID: 37210029 DOI: 10.1016/j.jmb.2023.168153] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 05/09/2023] [Accepted: 05/12/2023] [Indexed: 05/22/2023]
Abstract
Viral factories of liquid-like nature serve as sites for transcription and replication in most viruses. The respiratory syncytial virus factories include replication proteins, brought together by the phosphoprotein (P) RNA polymerase cofactor, present across non-segmented negative stranded RNA viruses. Homotypic liquid-liquid phase separation of RSV-P is governed by an α-helical molten globule domain, and strongly self-downmodulated by adjacent sequences. Condensation of P with the nucleoprotein N is stoichiometrically tuned, defining aggregate-droplet and droplet-dissolution boundaries. Time course analysis show small N-P nuclei gradually coalescing into large granules in transfected cells. This behavior is recapitulated in infection, with small puncta evolving to large viral factories, strongly suggesting that P-N nucleation-condensation sequentially drives viral factories. Thus, the tendency of P to undergo phase separation is moderate and latent in the full-length protein but unleashed in the presence of N or when neighboring disordered sequences are deleted. This, together with its capacity to rescue nucleoprotein-RNA aggregates suggests a role as a "solvent-protein".
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Affiliation(s)
- Mariano Salgueiro
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Gabriela Camporeale
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Araceli Visentin
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Martin Aran
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Leonardo Pellizza
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | | | - Agustín Corbat
- Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires, and IFIBA, CONICET, Buenos Aires, Argentina
| | - Hernán Grecco
- Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Buenos Aires, and IFIBA, CONICET, Buenos Aires, Argentina
| | - Belén Sousa
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Ramiro Esperón
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Silvia S Borkosky
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina
| | - Gonzalo de Prat-Gay
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) CONICET, Buenos Aires, Argentina.
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4
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Scudero OB, Santiago VF, Palmisano G, Simabuco FM, Ventura AM. The respiratory syncytial virus M2-2 protein is targeted for proteasome degradation and inhibits translation and stress granules assembly. PLoS One 2023; 18:e0289100. [PMID: 37490507 PMCID: PMC10368288 DOI: 10.1371/journal.pone.0289100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 07/12/2023] [Indexed: 07/27/2023] Open
Abstract
The M2-2 protein from the respiratory syncytial virus (RSV) is a 10 kDa protein expressed by the second ORF of the viral gene M2. During infection, M2-2 has been described as the polymerase cofactor responsible for promoting genome replication, which occurs by the induction of changes in interactions between the polymerase and other viral proteins at early stages of infection. Despite its well-explored role in the regulation of the polymerase activity, little has been made to investigate the relationship of M2-2 with cellular proteins. A previous report showed poor recruitment of M2-2 to viral structures, with the protein being mainly localized to the nucleus and cytoplasmic granules. To unravel which other functions M2-2 exerts during infection, we performed proteomic analysis of co-immunoprecipitated cellular partners, identifying enrichment of proteins involved with regulation of translation, protein folding and mRNA splicing. In approaches based on these data, we found that M2-2 expression downregulates eiF2α phosphorylation and inhibits both translation and stress granules assembly. Finally, we also verified that M2-2 is targeted for proteasome degradation, being localized to granules composed of defective ribosomal products at the cytoplasm. These results suggest that besides its functions in the replicative complex, M2-2 may exert additional functions to contribute to successful RSV infection.
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Affiliation(s)
- Orlando Bonito Scudero
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Verônica Feijoli Santiago
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Giuseppe Palmisano
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Fernando Moreira Simabuco
- Multidisciplinary Laboratory of Food and Health, School of Applied Sciences, University of Campinas, Limeira, São Paulo, Brazil
- Department of Biochemistry, Federal University of São Paulo, São Paulo, SP, Brazil
| | - Armando Morais Ventura
- Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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5
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Risso-Ballester J, Rameix-Welti MA. Spatial resolution of virus replication: RSV and cytoplasmic inclusion bodies. Adv Virus Res 2023; 116:1-43. [PMID: 37524479 DOI: 10.1016/bs.aivir.2023.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Respiratory Syncytial Virus (RSV) is a major cause of respiratory illness in young children, elderly and immunocompromised individuals worldwide representing a severe burden for health systems. The urgent development of vaccines or specific antivirals against RSV is impaired by the lack of knowledge regarding its replication mechanisms. RSV is a negative-sense single-stranded RNA (ssRNA) virus belonging to the Mononegavirales order (MNV) which includes other viruses pathogenic to humans as Rabies (RabV), Ebola (EBOV), or measles (MeV) viruses. Transcription and replication of viral genomes occur within cytoplasmatic virus-induced spherical inclusions, commonly referred as inclusion bodies (IBs). Recently IBs were shown to exhibit properties of membrane-less organelles (MLO) arising by liquid-liquid phase separation (LLPS). Compartmentalization of viral RNA synthesis steps in viral-induced MLO is indeed a common feature of MNV. Strikingly these key compartments still remain mysterious. Most of our current knowledge on IBs relies on the use of fluorescence microscopy. The ability to fluorescently label IBs in cells has been key to uncover their dynamics and nature. The generation of recombinant viruses expressing a fluorescently-labeled viral protein and the immunolabeling or the expression of viral fusion proteins known to be recruited in IBs are some of the tools used to visualize IBs in infected cells. In this chapter, microscope techniques and the most relevant studies that have shed light on RSV IBs fundamental aspects, including biogenesis, organization and dynamics are being discussed and brought to light with the investigations carried out on other MNV.
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Affiliation(s)
| | - Marie-Anne Rameix-Welti
- Institut Pasteur, Université Paris-Saclay, Université de Versailles St. Quentin, UMR 1173 (2I), INSERM, Paris, France; Assistance Publique des Hôpitaux de Paris, Hôpital Ambroise Paré, Laboratoire de Microbiologie, DMU15, Paris, France.
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6
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Visentin A, Demitroff N, Salgueiro M, Borkosky SS, Uversky VN, Camporeale G, de Prat-Gay G. Assembly of the Tripartite and RNA Condensates of the Respiratory Syncytial Virus Factory Proteins In Vitro: Role of the Transcription Antiterminator M 2-1. Viruses 2023; 15:1329. [PMID: 37376628 DOI: 10.3390/v15061329] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
A wide variety of viruses replicate in liquid-like viral factories. Non-segmented negative stranded RNA viruses share a nucleoprotein (N) and a phosphoprotein (P) that together emerge as the main drivers of liquid-liquid phase separation. The respiratory syncytial virus includes the transcription antiterminator M2-1, which binds RNA and maximizes RNA transcriptase processivity. We recapitulate the assembly mechanism of condensates of the three proteins and the role played by RNA. M2-1 displays a strong propensity for condensation by itself and with RNA through the formation of electrostatically driven protein-RNA coacervates based on the amphiphilic behavior of M2-1 and finely tuned by stoichiometry. M2-1 incorporates into tripartite condensates with N and P, modulating their size through an interplay with P, where M2-1 is both client and modulator. RNA is incorporated into the tripartite condensates adopting a heterogeneous distribution, reminiscent of the M2-1-RNA IBAG granules within the viral factories. Ionic strength dependence indicates that M2-1 behaves differently in the protein phase as opposed to the protein-RNA phase, in line with the subcompartmentalization observed in viral factories. This work dissects the biochemical grounds for the formation and fate of the RSV condensates in vitro and provides clues to interrogate the mechanism under the highly complex infection context.
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Affiliation(s)
- Araceli Visentin
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Nicolás Demitroff
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Mariano Salgueiro
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Silvia Susana Borkosky
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Gabriela Camporeale
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
| | - Gonzalo de Prat-Gay
- Instituto Leloir, IIB-BA Conicet, Av. Patricias Argentinas 435, Buenos Aires 1405, Argentina
- Brazilian Biosciences National Laboratory, Brazilian Center for Research in Energy and Materials (CNPEM), Campinas 13083-970, SP, Brazil
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7
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Sizun C. Biophysical Reviews' "Meet the Editors Series": a profile of Christina Sizun. Biophys Rev 2023; 15:301-304. [PMID: 37396447 PMCID: PMC10310629 DOI: 10.1007/s12551-023-01071-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2023] [Indexed: 07/04/2023] Open
Abstract
This edition of the continuing "Biophysical Reviews Meet the Editors Series" introduces Dr. Christina Sizun, physical chemist, member of the Biophysical Reviews editorial board and current Treasurer of the International Union for Pure and Applied Biophysics (IUPAB).
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Affiliation(s)
- Christina Sizun
- Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Université Paris-Saclay, Gif-sur-Yvette, France
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8
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Si F, Song S, Yu R, Li Z, Wei W, Wu C. Coronavirus accessory protein ORF3 biology and its contribution to viral behavior and pathogenesis. iScience 2023; 26:106280. [PMID: 36945252 PMCID: PMC9972675 DOI: 10.1016/j.isci.2023.106280] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
Coronavirus porcine epidemic diarrhea virus (PEDV) is classified in the genus Alphacoronavirus, family Coronaviridae that encodes the only accessory protein, ORF3 protein. However, how ORF3 contributes to viral pathogenicity, adaptability, and replication is obscure. In this review, we summarize current knowledge and identify gaps in many aspects of ORF3 protein in PEDV, with emphasis on its unique biological features, including membrane topology, Golgi retention mechanism, potential intrinsic disordered property, functional motifs, protein glycosylation, and codon usage phenotypes related to genetic evolution and gene expression. In addition, we propose intriguing questions related to ORF3 protein that we hope to stimulate further studies and encourage collaboration among virologists worldwide to provide constructive knowledge about the unique characteristics and biological functions of ORF3 protein, by which their potential role in clarifying viral behavior and pathogenesis can be possible.
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Affiliation(s)
- Fusheng Si
- Institute of Animal Science and Veterinary Medicine, Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, P.R. China
| | - Shuai Song
- Institute of Animal Health, Guangdong Academy of Agricultural Sciences, Scientific Observation and Experiment Station of Veterinary Drugs and Diagnostic Techniques of Guangdong Province, Ministry of Agriculture of Rural Affairs, and Key Laboratory of Animal Disease Prevention of Guangdong Province, Guangzhou 510640, P.R. China
| | - Ruisong Yu
- Institute of Animal Science and Veterinary Medicine, Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, P.R. China
| | - Zhen Li
- Institute of Animal Science and Veterinary Medicine, Shanghai Academy of Agricultural Sciences, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, P.R. China
| | - Wenqiang Wei
- Department of Microbiology, School of Basic Medical Sciences, Henan University, Kaifeng, Henan 475004, P.R. China
| | - Chao Wu
- Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, MO 63110, USA
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9
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Sutto-Ortiz P, Eléouët JF, Ferron F, Decroly E. Biochemistry of the Respiratory Syncytial Virus L Protein Embedding RNA Polymerase and Capping Activities. Viruses 2023; 15:v15020341. [PMID: 36851554 PMCID: PMC9960070 DOI: 10.3390/v15020341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/12/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023] Open
Abstract
The human respiratory syncytial virus (RSV) is a negative-sense, single-stranded RNA virus. It is the major cause of severe acute lower respiratory tract infection in infants, the elderly population, and immunocompromised individuals. There is still no approved vaccine or antiviral treatment against RSV disease, but new monoclonal prophylactic antibodies are yet to be commercialized, and clinical trials are in progress. Hence, urgent efforts are needed to develop efficient therapeutic treatments. RSV RNA synthesis comprises viral transcription and replication that are catalyzed by the large protein (L) in coordination with the phosphoprotein polymerase cofactor (P), the nucleoprotein (N), and the M2-1 transcription factor. The replication/transcription is orchestrated by the L protein, which contains three conserved enzymatic domains: the RNA-dependent RNA polymerase (RdRp), the polyribonucleotidyl transferase (PRNTase or capping), and the methyltransferase (MTase) domain. These activities are essential for the RSV replicative cycle and are thus considered as attractive targets for the development of therapeutic agents. In this review, we summarize recent findings about RSV L domains structure that highlight how the enzymatic activities of RSV L domains are interconnected, discuss the most relevant and recent antivirals developments that target the replication/transcription complex, and conclude with a perspective on identified knowledge gaps that enable new research directions.
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Affiliation(s)
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, F78350 Jouy en Josas, France
| | - François Ferron
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- European Virus Bioinformatics Center, Leutragraben 1, 07743 Jena, Germany
| | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB, UMR, 7257 Marseille, France
- Correspondence:
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10
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Xue Y, Shi X, Feng D, Wang Y. The binding affinity of human pediatric respiratory syncytial virus Phosphoprotein's C-terminal tail to nucleocapsid can be improved by a rationally designed halogen-bonded system. J Mol Graph Model 2023; 118:108374. [PMID: 36401896 DOI: 10.1016/j.jmgm.2022.108374] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/27/2022] [Accepted: 11/03/2022] [Indexed: 11/10/2022]
Abstract
Human respiratory syncytial virus (hRSV) is a common contagious virus that causes infections of pediatric pneumonia and specifically impacts infants and small children. The hRSV phosphoprotein is a key component of the viral RNA polymerase, which can interact with nucleocapsid and other partners through its C-terminal tail (CTT) to promote the formation of viral transcriptase complex, where the Phe241 is a key anchor residue. Based on the crystal template-modeled complex structure of hRSV nucleocapsid with a peptidic segment derived from the phosphoprotein's CTT, we successfully introduced a rationally designed halogen-bonded system to the complex interface by substituting para (p)-position of the side-chain phenyl moiety of CTT Phe241 residue with a halogen atom X (X = F, Cl, Br or I). The halogen-bonded system consists of a halogen bond (X-bond) between nucleocapsid Ser131 residue and CTT Phe241 residue as well as a hydrogen bond (H-bond) between nucleocapsid Ser131 residue and nucleocapsid Glu128 residue; the X-bond and H-bond share a common hydroxyl group of nucleocapsid Ser131 residue. High-level theoretical calculations suggested that bromine Br is the best choice that can render strong potency for the X-bond and can confer high affinity to the nucleocapsid-CTT binding. Affinity analysis revealed that the p-brominated CTT ([p]bCTT) exhibited 6.3-fold affinity improvement relative to its nonhalogenated counterpart. In contrast, the Br-substitutions at ortho (o)- and meta (m)-positions, which resulted in two negative controls of o-brominated [o]bCTT and m-brominated [m]bCTT, respectively, were unable to form effective X-bond with nucleocapsid according to theoretical investigation and did not improve the binding affinity essentially relative to native CTT.
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Affiliation(s)
- Yaqi Xue
- Department of Pediatrics, Affiliated Huaian Hospital of Xuzhou Medical University, Huaian, 223001, China
| | - Xiangxiang Shi
- Department of Pediatrics, Affiliated Huaian Hospital of Xuzhou Medical University, Huaian, 223001, China
| | - Dengmei Feng
- Department of Pediatrics, Lianshui People Hospital, Affiliated to Kangda College of Nanjing Medical University, Lianshui, 223400, China
| | - Yunhong Wang
- Department of Pediatrics, Lianshui People Hospital, Affiliated to Kangda College of Nanjing Medical University, Lianshui, 223400, China.
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11
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Liu H, Shen L, Pan C, Huang W. Structural modeling, energetic analysis and molecular design of a π-stacking system at the complex interface of pediatric respiratory syncytial virus nucleocapsid with the C-terminal peptide of phosphoprotein. Biophys Chem 2023; 292:106916. [PMID: 36343393 DOI: 10.1016/j.bpc.2022.106916] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 10/14/2022] [Accepted: 10/23/2022] [Indexed: 11/02/2022]
Abstract
Human respiratory syncytial virus (RSV) is a primary cause of lower respiratory tract infections and hospital visits during infancy and childhood. The RSV phosphoprotein (P) is a major polymerase cofactor that interacts with nucleoprotein (N) to promote the recognition of ribonucleoprotein complex (RNP) by viral RNA polymerase. The binding pocket of N protein is chemically diverse, in or around which a number of aromatic and charged amino acid residues are observed. Previously, a nonapeptide segment (P peptide, 233DNDLSLEDF241) representing the C-terminal tail of P protein was identified to mediate the N-P interaction with a moderate affinity, in which the Phe241 at the end of P's C-terminus plays a critical role in the binding of P peptide to N protein. Here, we found that the side-chain aromatic phenyl moiety of P Phe241 residue can form short- and long-range cation-π interactions with N Arg132 and Arg150 residues, respectively, as well as T-shaped and parallel-displaced π-π stackings with N Tyr135 and His151 residues, respectively, which co-define a geometrically satisfactory π-stacking system at the complex interface of N protein with P peptide, thus largely stabilizing the complex architecture. The stacking effect was further optimized by systematically mutating the P Phe241 residue to other natural and non-natural aromatic amino acids with diverse chemical substitutions at the phenyl moiety to examine their structural and energetic effects on π-stacking system and on protein-peptide binding. The electron-donating mutations at the phenyl moiety of P Phe241 residue can effectively enhance the π-stacking system and then promote peptide binding, whereas the bulky and positively charged mutations would considerably impair the peptide potency by introducing steric hindrance and electrostatic repulsion. The [Tyr]P, [Thp]P and [Fph]P mutants were determined to have an increased affinity relative to wild-type P peptide, which could be used as self-inhibitory peptides to competitively disrupt the native interaction between N and P proteins.
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Affiliation(s)
- Haiyan Liu
- Department of Pediatrics, Suzhou Kowloon Hospital, Shanghai Jiao Tong University School of Medicine, Suzhou 215000, China
| | - Lili Shen
- Department of Pediatrics, Suzhou Kowloon Hospital, Shanghai Jiao Tong University School of Medicine, Suzhou 215000, China
| | - Chunhua Pan
- Department of Pediatrics, Suzhou Kowloon Hospital, Shanghai Jiao Tong University School of Medicine, Suzhou 215000, China
| | - Weihua Huang
- Department of Pediatrics, Suzhou Kowloon Hospital, Shanghai Jiao Tong University School of Medicine, Suzhou 215000, China.
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12
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Investigation of the Fuzzy Complex between RSV Nucleoprotein and Phosphoprotein to Optimize an Inhibition Assay by Fluorescence Polarization. Int J Mol Sci 2022; 24:ijms24010569. [PMID: 36614009 PMCID: PMC9820559 DOI: 10.3390/ijms24010569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022] Open
Abstract
The interaction between Respiratory Syncytial Virus phosphoprotein P and nucleoprotein N is essential for the formation of the holo RSV polymerase that carries out replication. In vitro screening of antivirals targeting the N-P protein interaction requires a molecular interaction model, ideally consisting of a complex between N protein and a short peptide corresponding to the C-terminal tail of the P protein. However, the flexibility of C-terminal P peptides as well as their phosphorylation status play a role in binding and may bias the outcome of an inhibition assay. We therefore investigated binding affinities and dynamics of this interaction by testing two N protein constructs and P peptides of different lengths and composition, using nuclear magnetic resonance and fluorescence polarization (FP). We show that, although the last C-terminal Phe241 residue is the main determinant for anchoring P to N, only longer peptides afford sub-micromolar affinity, despite increasing mobility towards the N-terminus. We investigated competitive binding by peptides and small compounds, including molecules used as fluorescent labels in FP. Based on these results, we draw optimized parameters for a robust RSV N-P inhibition assay and validated this assay with the M76 molecule, which displays antiviral properties, for further screening of chemical libraries.
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Zhang L, Gong Y, Shen L. Molecular Stapling of Human Pediatric RSV Phosphoprotein’s C-terminal Tail-Derived Peptides to Target the Coupled Folding-Upon-Binding Event Between Phosphoprotein and Nucleocapsid. Int J Pept Res Ther 2022. [DOI: 10.1007/s10989-022-10483-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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14
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Respiratory Syncytial virus NS1 protein targets the transactivator binding domain of MED25. J Mol Biol 2022; 434:167763. [PMID: 35907573 DOI: 10.1016/j.jmb.2022.167763] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 06/28/2022] [Accepted: 07/21/2022] [Indexed: 11/20/2022]
Abstract
Human RSV is the leading cause of infantile bronchiolitis in the world and one of the major causes of childhood deaths in resource-poor settings. It is a major unmet target for vaccines and anti-viral drugs. Respiratory syncytial virus has evolved a unique strategy to evade host immune response by coding for two non-structural proteins NS1 and NS2. Recently it was shown that in infected cells, nuclear NS1 could be involved in transcription regulation of host genes linked to innate immune response, via interactions with chromatin and the Mediator complex. Here we identified the MED25 Mediator subunit as an NS1 interactor in a yeast two-hybrid screen. We demonstrate that NS1 directly interacts with MED25 in vitro and in cellula, and that this interaction involves the MED25 transactivator binding ACID domain on the one hand, and the C-terminal α3 helix of NS1, with an additional contribution of the globular domain of NS1, on the other hand. By NMR we show that the NS1 α3 sequence primarily binds to the MED25 ACID H2 face, similarly to the α-helical transactivation domains (TADs) of transcription regulators such as Herpex simplex VP16 and ATF6α, a master regulator of ER stress response activated upon viral infection. Moreover, we found out that the NS1 could compete with ATF6α TAD for binding to MED25. These findings point to a mechanism of NS1 interfering with innate immune response by impairing recruitment by cellular TADs of the Mediator via MED25 and hence transcription of specific genes by RNA polymerase II.
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15
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Chen JW, Yang L, Santos C, Hassan SA, Collins PL, Buchholz UJ, Le Nouën C. Reversion mutations in phosphoprotein P of a codon-pair-deoptimized human respiratory syncytial virus confer increased transcription, immunogenicity, and genetic stability without loss of attenuation. PLoS Pathog 2021; 17:e1010191. [PMID: 34965283 PMCID: PMC8751989 DOI: 10.1371/journal.ppat.1010191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 01/11/2022] [Accepted: 12/09/2021] [Indexed: 11/18/2022] Open
Abstract
Recoding viral genomes by introducing numerous synonymous nucleotide substitutions that create suboptimal codon pairs provides new live-attenuated vaccine candidates. Because recoding typically involves a large number of nucleotide substitutions, the risk of de-attenuation is presumed to be low. However, this has not been thoroughly studied. We previously generated human respiratory syncytial virus (RSV) in which the NS1, NS2, N, P, M and SH ORFs were codon-pair deoptimized (CPD) by 695 synonymous nucleotide changes (Min A virus). Min A exhibited a global reduction in transcription and protein synthesis, was restricted for replication in vitro and in vivo, and exhibited moderate temperature sensitivity. Here, we show that under selective pressure by serial passage at progressively increasing temperatures, Min A regained replication fitness and lost its temperature sensitivity. Whole-genome deep sequencing identified numerous missense mutations in several genes, in particular ones accumulating between codons 25 and 34 of the phosphoprotein (P), a polymerase cofactor and chaperone. When re-introduced into Min A, these P mutations restored viral transcription to wt level, resulting in increased protein expression and RNA replication. Molecular dynamic simulations suggested that these P mutations increased the flexibility of the N-terminal domain of P, which might facilitate its interaction with the nucleoprotein N, and increase the functional efficiency of the RSV transcription/replication complex. Finally, we evaluated the effect of the P mutations on Min A replication and immunogenicity in hamsters. Mutation P[F28V] paradoxically reduced Min A replication but not its immunogenicity. The further addition of one missense mutation each in M and L generated a version of Min A with increased genetic stability. Thus, this study provides further insight into the adaptability of large-scale recoded RNA viruses under selective pressure and identified an improved CPD RSV vaccine candidate. Synonymous recoding of viral genomes by codon-pair deoptimization (CPD) generates live-attenuated vaccines presumed to be genetically stable due to the high number of nucleotide substitutions. However, their actual genetic stability under selective pressure was largely unknown. In a recoded human respiratory syncytial virus (RSV) mutant called Min A, six of 11 ORFs were CPD, reducing protein expression and inducing moderate temperature sensitivity and attenuation. When passaged in vitro under selective pressure, Min A lost its temperature-sensitive phenotype and regained fitness by the acquisition of numerous mutations, in particular missense mutations in the viral phosphoprotein (P), a polymerase cofactor and a chaperone for soluble nucleoprotein. These P mutations increased RSV gene transcription globally, thereby increasing RSV protein expression, RNA replication, and virus particle production. Thus, the P mutations increased the efficiency of the RSV transcription/replication complex, compensating for the reduced protein expression due to CPD. In addition, introduction of the P mutations into Min A generated a live-attenuated vaccine candidate with increased genetic stability. Surprisingly, this vaccine candidate exhibited increased attenuation and, paradoxically, exhibited increased immunogenicity per plaque-forming unit in hamsters. This study provides insights into the adaptability of large-scale recoded RNA viruses and identified an improved CPD RSV vaccine candidate.
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Affiliation(s)
- Jessica W. Chen
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Lijuan Yang
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Celia Santos
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Sergio A. Hassan
- Bioinformatics and Computational Biosciences Branch, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Peter L. Collins
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Ursula J. Buchholz
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
| | - Cyril Le Nouën
- RNA Viruses Section, Laboratory of Infectious Diseases, NIAID, NIH, Bethesda, Maryland, United States of America
- * E-mail:
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The Nucleocapsid of Paramyxoviruses: Structure and Function of an Encapsidated Template. Viruses 2021; 13:v13122465. [PMID: 34960734 PMCID: PMC8708338 DOI: 10.3390/v13122465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/07/2021] [Accepted: 12/07/2021] [Indexed: 01/28/2023] Open
Abstract
Viruses of the Paramyxoviridae family share a common and complex molecular machinery for transcribing and replicating their genomes. Their non-segmented, negative-strand RNA genome is encased in a tight homopolymer of viral nucleoproteins (N). This ribonucleoprotein complex, termed a nucleocapsid, is the template of the viral polymerase complex made of the large protein (L) and its co-factor, the phosphoprotein (P). This review summarizes the current knowledge on several aspects of paramyxovirus transcription and replication, including structural and functional data on (1) the architecture of the nucleocapsid (structure of the nucleoprotein, interprotomer contacts, interaction with RNA, and organization of the disordered C-terminal tail of N), (2) the encapsidation of the genomic RNAs (structure of the nucleoprotein in complex with its chaperon P and kinetics of RNA encapsidation in vitro), and (3) the use of the nucleocapsid as a template for the polymerase complex (release of the encased RNA and interaction network allowing the progress of the polymerase complex). Finally, this review presents models of paramyxovirus transcription and replication.
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Interactions between the Nucleoprotein and the Phosphoprotein of Pneumoviruses: Structural Insight for Rational Design of Antivirals. Viruses 2021; 13:v13122449. [PMID: 34960719 PMCID: PMC8706346 DOI: 10.3390/v13122449] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 11/30/2021] [Accepted: 12/01/2021] [Indexed: 11/17/2022] Open
Abstract
Pneumoviruses include pathogenic human and animal viruses, the most known and studied being the human respiratory syncytial virus (hRSV) and the metapneumovirus (hMPV), which are the major cause of severe acute respiratory tract illness in young children worldwide, and main pathogens infecting elderly and immune-compromised people. The transcription and replication of these viruses take place in specific cytoplasmic inclusions called inclusion bodies (IBs). These activities depend on viral polymerase L, associated with its cofactor phosphoprotein P, for the recognition of the viral RNA genome encapsidated by the nucleoprotein N, forming the nucleocapsid (NC). The polymerase activities rely on diverse transient protein-protein interactions orchestrated by P playing the hub role. Among these interactions, P interacts with the NC to recruit L to the genome. The P protein also plays the role of chaperone to maintain the neosynthesized N monomeric and RNA-free (called N0) before specific encapsidation of the viral genome and antigenome. This review aims at giving an overview of recent structural information obtained for hRSV and hMPV P, N, and more specifically for P-NC and N0-P complexes that pave the way for the rational design of new antivirals against those viruses.
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Cardone C, Caseau CM, Bardiaux B, Thureaux A, Galloux M, Bajorek M, Eléouët JF, Litaudon M, Bontems F, Sizun C. A Structural and Dynamic Analysis of the Partially Disordered Polymerase-Binding Domain in RSV Phosphoprotein. Biomolecules 2021; 11:biom11081225. [PMID: 34439894 PMCID: PMC8392014 DOI: 10.3390/biom11081225] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/10/2021] [Accepted: 08/13/2021] [Indexed: 12/11/2022] Open
Abstract
The phosphoprotein P of Mononegavirales (MNV) is an essential co-factor of the viral RNA polymerase L. Its prime function is to recruit L to the ribonucleocapsid composed of the viral genome encapsidated by the nucleoprotein N. MNV phosphoproteins often contain a high degree of disorder. In Pneumoviridae phosphoproteins, the only domain with well-defined structure is a small oligomerization domain (POD). We previously characterized the differential disorder in respiratory syncytial virus (RSV) phosphoprotein by NMR. We showed that outside of RSV POD, the intrinsically disordered N-and C-terminal regions displayed a structural and dynamic diversity ranging from random coil to high helical propensity. Here we provide additional insight into the dynamic behavior of PCα, a domain that is C-terminal to POD and constitutes the RSV L-binding region together with POD. By using small phosphoprotein fragments centered on or adjacent to POD, we obtained a structural picture of the POD–PCα region in solution, at the single residue level by NMR and at lower resolution by complementary biophysical methods. We probed POD–PCα inter-domain contacts and showed that small molecules were able to modify the dynamics of PCα. These structural properties are fundamental to the peculiar binding mode of RSV phosphoprotein to L, where each of the four protomers binds to L in a different way.
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Affiliation(s)
- Christophe Cardone
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Claire-Marie Caseau
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Benjamin Bardiaux
- Structural Bioinformatics Unit, Department of Structural Biology and Chemistry, Institut Pasteur, CNRS UMR3528, 78015 Paris, France;
| | | | - Marie Galloux
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Monika Bajorek
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRAE, Université Paris Saclay, 78352 Jouy-en-Josas, France; (M.G.); (M.B.); (J.-F.E.)
| | - Marc Litaudon
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - François Bontems
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, 91190 Gif-sur-Yvette, France; (C.C.); (C.-M.C.); (M.L.); (F.B.)
- Correspondence:
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19
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Fearns R. Negative‐strand RNA Viruses. Virology 2021. [DOI: 10.1002/9781119818526.ch3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Tetramerization of Phosphoprotein is Essential for Respiratory Syncytial Virus Budding while its N Terminal Region Mediates Direct Interactions with the Matrix Protein. J Virol 2021; 95:JVI.02217-20. [PMID: 33408180 PMCID: PMC8092690 DOI: 10.1128/jvi.02217-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
It was shown previously that the Matrix (M), Phosphoprotein (P), and the Fusion (F) proteins of Respiratory syncytial virus (RSV) are sufficient to produce virus-like particles (VLPs) that resemble the RSV infection-induced virions. However, the exact mechanism and interactions among the three proteins are not known. This work examines the interaction between P and M during RSV assembly and budding. We show that M interacts with P in the absence of other viral proteins in cells using a Split Nano Luciferase assay. By using recombinant proteins, we demonstrate a direct interaction between M and P. By using Nuclear Magnetic Resonance (NMR) we identify three novel M interaction sites on P, namely site I in the αN2 region, site II in the 115-125 region, and the oligomerization domain (OD). We show that the OD, and likely the tetrameric structural organization of P, is required for virus-like filament formation and VLP release. Although sites I and II are not required for VLP formation, they appear to modulate P levels in RSV VLPs.Importance Human RSV is the commonest cause of infantile bronchiolitis in the developed world and of childhood deaths in resource-poor settings. It is a major unmet target for vaccines and anti-viral drugs. The lack of knowledge of RSV budding mechanism presents a continuing challenge for VLP production for vaccine purpose. We show that direct interaction between P and M modulates RSV VLP budding. This further emphasizes P as a central regulator of RSV life cycle, as an essential actor for transcription and replication early during infection and as a mediator for assembly and budding in the later stages for virus production.
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21
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Cardone C, Caseau CM, Pereira N, Sizun C. Pneumoviral Phosphoprotein, a Multidomain Adaptor-Like Protein of Apparent Low Structural Complexity and High Conformational Versatility. Int J Mol Sci 2021; 22:ijms22041537. [PMID: 33546457 PMCID: PMC7913705 DOI: 10.3390/ijms22041537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 01/31/2021] [Accepted: 02/01/2021] [Indexed: 01/16/2023] Open
Abstract
Mononegavirales phosphoproteins (P) are essential co-factors of the viral polymerase by serving as a linchpin between the catalytic subunit and the ribonucleoprotein template. They have highly diverged, but their overall architecture is conserved. They are multidomain proteins, which all possess an oligomerization domain that separates N- and C-terminal domains. Large intrinsically disordered regions constitute their hallmark. Here, we exemplify their structural features and interaction potential, based on the Pneumoviridae P proteins. These P proteins are rather small, and their oligomerization domain is the only part with a defined 3D structure, owing to a quaternary arrangement. All other parts are either flexible or form short-lived secondary structure elements that transiently associate with the rest of the protein. Pneumoviridae P proteins interact with several viral and cellular proteins that are essential for viral transcription and replication. The combination of intrinsic disorder and tetrameric organization enables them to structurally adapt to different partners and to act as adaptor-like platforms to bring the latter close in space. Transient structures are stabilized in complex with protein partners. This class of proteins gives an insight into the structural versatility of non-globular intrinsically disordered protein domains.
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Minimal Elements Required for the Formation of Respiratory Syncytial Virus Cytoplasmic Inclusion Bodies In Vivo and In Vitro. mBio 2020; 11:mBio.01202-20. [PMID: 32963000 PMCID: PMC7512546 DOI: 10.1128/mbio.01202-20] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract illness in infants, elderly, and immunocompromised people. No vaccine or efficient antiviral treatment is available against this virus. The replication and transcription steps of the viral genome are appealing mechanisms to target for the development of new antiviral strategies. These activities take place within cytoplasmic inclusion bodies (IBs) that assemble during infection. Although expression of both the viral nucleoprotein (N) and phosphoprotein (P) allows induction of the formation of these IBs, the mechanism sustaining their assembly remains poorly characterized. Here, we identified key elements of N and P required for the scaffolding of IBs and managed for the first time to reconstitute RSV pseudo-IBs in vitro by coincubating recombinant N and P proteins. Our results provide strong evidence that the biogenesis of RSV IBs occurs through liquid-liquid phase transition mediated by N-P interactions. Infection of host cells by the respiratory syncytial virus (RSV) is characterized by the formation of spherical cytoplasmic inclusion bodies (IBs). These structures, which concentrate all the proteins of the polymerase complex as well as some cellular proteins, were initially considered aggresomes formed by viral dead-end products. However, recent studies revealed that IBs are viral factories where viral RNA synthesis, i.e., replication and transcription, occurs. The analysis of IBs by electron microscopy revealed that they are membrane-less structures, and accumulated data on their structure, organization, and kinetics of formation revealed that IBs share the characteristics of cellular organelles, such as P-bodies or stress granules, suggesting that their morphogenesis depends on a liquid-liquid phase separation mechanism. It was previously shown that expression of the RSV nucleoprotein N and phosphoprotein P of the polymerase complex is sufficient to induce the formation of pseudo-IBs. Here, using a series of truncated P proteins, we identified the domains of P required for IB formation and show that the oligomeric state of N, provided it can interact with RNA, is critical for their morphogenesis. We also show that pseudo-IBs can form in vitro when recombinant N and P proteins are mixed. Finally, using fluorescence recovery after photobleaching approaches, we reveal that in cellula and in vitro IBs are liquid organelles. Our results strongly support the liquid-liquid phase separation nature of IBs and pave the way for further characterization of their dynamics.
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Targeting the Respiratory Syncytial Virus N 0-P Complex with Constrained α-Helical Peptides in Cells and Mice. Antimicrob Agents Chemother 2020; 64:AAC.00717-20. [PMID: 32660994 PMCID: PMC7508628 DOI: 10.1128/aac.00717-20] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 06/30/2020] [Indexed: 02/07/2023] Open
Abstract
Respiratory syncytial virus (RSV) is the main cause of severe respiratory infection in young children worldwide, and no therapies have been approved for the treatment of RSV infection. Data from recent clinical trials of fusion or L polymerase inhibitors for the treatment of RSV-infected patients revealed the emergence of escape mutants, highlighting the need for the discovery of inhibitors with novel mechanisms of action. Here we describe stapled peptides derived from the N terminus of the phosphoprotein (P) that act as replication inhibitors. Respiratory syncytial virus (RSV) is the main cause of severe respiratory infection in young children worldwide, and no therapies have been approved for the treatment of RSV infection. Data from recent clinical trials of fusion or L polymerase inhibitors for the treatment of RSV-infected patients revealed the emergence of escape mutants, highlighting the need for the discovery of inhibitors with novel mechanisms of action. Here we describe stapled peptides derived from the N terminus of the phosphoprotein (P) that act as replication inhibitors. We demonstrate that these peptides inhibit RSV replication in vitro and in vivo by preventing the formation of the N0-P complex. The present strategy provides a novel means of targeting RSV replication with constrained macrocyclic peptides or small molecules and is broadly applicable to other viruses of the Mononegavirales order.
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Hara K, Yaita K, Khamrin P, Kumthip K, Kashiwagi T, Eléouët JF, Rameix-Welti MA, Watanabe H. A small fragmented P protein of respiratory syncytial virus inhibits virus infection by targeting P protein. J Gen Virol 2020; 101:21-32. [PMID: 31702536 DOI: 10.1099/jgv.0.001350] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Peptide-based inhibitors hold promising potential in the development of antiviral therapy. Here, we investigated the antiviral potential of fragmented viral proteins derived from ribonucleoprotein (RNP) components of the human respiratory syncytial virus (HRSV). Based on a mimicking approach that targets the functional domains of viral proteins, we designed various fragments of nucleoprotein (N), matrix protein M2-1 and phosphoprotein (P) and tested the antiviral activity in an RSV mini-genome system. We found that the fragment comprising residues 130-180 and 212-241 in the C-terminal region of P (81 amino acid length), denoted as P Fr, significantly inhibited the polymerase activity through competitive binding to the full-length P. Further deletion analysis of P Fr suggested that three functional domains in P Fr (oligomerization, L-binding and nucleocapsid binding) are required for maximum inhibitory activity. More importantly, a purified recombinant P Fr displayed significant antiviral activity at low nanomolar range in RSV-infected HEp-2 cells. These results highlight P as an important target for the development of antiviral compounds against RSV and other paramyxoviruses.
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Affiliation(s)
- Koyu Hara
- Department of Infection Control and Prevention, Kurume University School of Medicine, Fukuoka, 830-0011, Japan
| | - Kenichiro Yaita
- Division of Infectious diseases, Chidoribashi General Hospital, Fukuoka 812-8633, Japan
| | - Pattara Khamrin
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Kattareeya Kumthip
- Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Takahito Kashiwagi
- Department of Infection Control and Prevention, Kurume University School of Medicine, Fukuoka, 830-0011, Japan
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Marie-Anne Rameix-Welti
- AP-HP, Laboratoire de Microbiologie, Hôpital Ambroise Paré, Boulogne-Billancourt, France.,UMR1173, INSERM, Université de Versailles St. Quentin, Montigny le Bretonneux, France
| | - Hiroshi Watanabe
- Department of Infection Control and Prevention, Kurume University School of Medicine, Fukuoka, 830-0011, Japan
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Cao D, Gao Y, Roesler C, Rice S, D'Cunha P, Zhuang L, Slack J, Domke M, Antonova A, Romanelli S, Keating S, Forero G, Juneja P, Liang B. Cryo-EM structure of the respiratory syncytial virus RNA polymerase. Nat Commun 2020; 11:368. [PMID: 31953395 PMCID: PMC6969064 DOI: 10.1038/s41467-019-14246-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/18/2019] [Indexed: 12/21/2022] Open
Abstract
The respiratory syncytial virus (RSV) RNA polymerase, constituted of a 250 kDa large (L) protein and tetrameric phosphoprotein (P), catalyzes three distinct enzymatic activities — nucleotide polymerization, cap addition, and cap methylation. How RSV L and P coordinate these activities is poorly understood. Here, we present a 3.67 Å cryo-EM structure of the RSV polymerase (L:P) complex. The structure reveals that the RNA dependent RNA polymerase (RdRp) and capping (Cap) domains of L interact with the oligomerization domain (POD) and C-terminal domain (PCTD) of a tetramer of P. The density of the methyltransferase (MT) domain of L and the N-terminal domain of P (PNTD) is missing. Further analysis and comparison with other RNA polymerases at different stages suggest the structure we obtained is likely to be at an elongation-compatible stage. Together, these data provide enriched insights into the interrelationship, the inhibitors, and the evolutionary implications of the RSV polymerase. Respiratory syncytial virus (RSV) is a pathogenic non-segmented negative-sense RNA virus and active RSV polymerase is composed of a 250 kDa large (L) protein and tetrameric phosphoprotein (P). Here, the authors present the 3.67 Å cryo-EM structure of the RSV polymerase (L:P) complex.
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Affiliation(s)
- Dongdong Cao
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Yunrong Gao
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Claire Roesler
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Samantha Rice
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Paul D'Cunha
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Lisa Zhuang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Julia Slack
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Mason Domke
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Anna Antonova
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Sarah Romanelli
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Shayon Keating
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Gabriela Forero
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Puneet Juneja
- Robert P. Apkarian Integrated Electron Microscopy Core, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Bo Liang
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, 30322, USA.
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26
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The Respiratory Syncytial Virus Polymerase: A Multitasking Machine. Trends Microbiol 2019; 27:969-971. [PMID: 31672264 DOI: 10.1016/j.tim.2019.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/07/2019] [Indexed: 11/21/2022]
Abstract
Respiratory syncytial virus (RSV) inflicts a significant toll on human life. An essential element of the virus is its polymerase, a complex capable of transcribing and replicating the viral genome. In an exciting new advance, Gilman et al. resolve the structure of this polymerase, providing valuable mechanistic insight into its activities.
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27
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Gilman MSA, Liu C, Fung A, Behera I, Jordan P, Rigaux P, Ysebaert N, Tcherniuk S, Sourimant J, Eléouët JF, Sutto-Ortiz P, Decroly E, Roymans D, Jin Z, McLellan JS. Structure of the Respiratory Syncytial Virus Polymerase Complex. Cell 2019; 179:193-204.e14. [PMID: 31495574 PMCID: PMC7111336 DOI: 10.1016/j.cell.2019.08.014] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/03/2019] [Accepted: 08/06/2019] [Indexed: 01/29/2023]
Abstract
Numerous interventions are in clinical development for respiratory syncytial virus (RSV) infection, including small molecules that target viral transcription and replication. These processes are catalyzed by a complex comprising the RNA-dependent RNA polymerase (L) and the tetrameric phosphoprotein (P). RSV P recruits multiple proteins to the polymerase complex and, with the exception of its oligomerization domain, is thought to be intrinsically disordered. Despite their critical roles in RSV transcription and replication, structures of L and P have remained elusive. Here, we describe the 3.2-Å cryo-EM structure of RSV L bound to tetrameric P. The structure reveals a striking tentacular arrangement of P, with each of the four monomers adopting a distinct conformation. The structure also rationalizes inhibitor escape mutants and mutations observed in live-attenuated vaccine candidates. These results provide a framework for determining the molecular underpinnings of RSV replication and transcription and should facilitate the design of effective RSV inhibitors.
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Affiliation(s)
- Morgan S A Gilman
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Cheng Liu
- Janssen BioPharma, Inc., Janssen Pharmaceutical Companies, South San Francisco, CA 94080, USA
| | - Amy Fung
- Janssen BioPharma, Inc., Janssen Pharmaceutical Companies, South San Francisco, CA 94080, USA
| | - Ishani Behera
- Janssen BioPharma, Inc., Janssen Pharmaceutical Companies, South San Francisco, CA 94080, USA
| | - Paul Jordan
- Janssen BioPharma, Inc., Janssen Pharmaceutical Companies, South San Francisco, CA 94080, USA
| | - Peter Rigaux
- Janssen Infectious Diseases and Vaccines, 2340 Beerse, Belgium
| | - Nina Ysebaert
- Janssen Infectious Diseases and Vaccines, 2340 Beerse, Belgium
| | - Sergey Tcherniuk
- Unité de Virologie et Immunologie Moléculaires, INRA, Université Paris Saclay, 78350 Jouy en Josas, France
| | - Julien Sourimant
- Unité de Virologie et Immunologie Moléculaires, INRA, Université Paris Saclay, 78350 Jouy en Josas, France
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRA, Université Paris Saclay, 78350 Jouy en Josas, France
| | | | - Etienne Decroly
- Aix Marseille Université, CNRS, AFMB UMR 7257, Marseille, France
| | - Dirk Roymans
- Janssen Infectious Diseases and Vaccines, 2340 Beerse, Belgium
| | - Zhinan Jin
- Janssen BioPharma, Inc., Janssen Pharmaceutical Companies, South San Francisco, CA 94080, USA
| | - Jason S McLellan
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX 78712, USA.
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28
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Alvarez Paggi D, Esperante SA, Salgueiro M, Camporeale G, de Oliveira GAP, Prat Gay G. A conformational switch balances viral RNA accessibility and protection in a nucleocapsid ring model. Arch Biochem Biophys 2019; 671:77-86. [PMID: 31229488 DOI: 10.1016/j.abb.2019.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/30/2019] [Accepted: 06/19/2019] [Indexed: 12/22/2022]
Abstract
Virus from the Mononegavirales order share common features ranging from virion structure arrangement to mechanisms of replication and transcription. One of them is the way the nucleoprotein (N) wraps and protects the RNA genome from degradation by forming a highly ordered helical nucleocapsid. However, crystal structures from numerous Mononegavirales reveal that binding to the nucleoprotein results in occluded nucleotides that hinder base pairing necessary for transcription and replication. This hints at the existence of alternative conformations of the N protein that would impact on the protein-RNA interface, allowing for transient exposure of the nucleotides without complete RNA release. Moreover, the regulation between the alternative conformations should be finely tuned. Recombinant expression of N from the respiratory syncytial virus form regular N/RNA common among all Mononegavirales, and these constitute an ideal minimal unit for investigating the mechanisms through which these structures protect RNA so efficiently while allowing for partial accessibility during transcription and replication. Neither pH nor high ionic strength could dissociate the RNA but led to irreversible aggregation of the nucleoprotein. Low concentrations of guanidine chloride dissociated the RNA moiety but leading to irreversible aggregation of the protein moiety. On the other hand, high concentrations of urea and long incubation periods were required to remove bound RNA. Both denaturants eventually led to unfolding but converged in the formation of an RNA-free β-enriched intermediate species that remained decameric even at high denaturant concentrations. Although the N-RNA rings interact with the phosphoprotein P, the scaffold of the RNA polymerase complex, this interaction did not lead to RNA dissociation from the rings in vitro. Thus, we have uncovered complex equilibria involving changes in secondary structure of N and RNA loosening, processes that must take place in the context of RNA transcription and replication, whose detailed mechanisms and cellular and viral participants need to be established.
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Affiliation(s)
- D Alvarez Paggi
- Protein Structure-Function and Engineering Laboratory, Fundación Instituto Leloir and IIBBA-CONICET, Argentina.
| | - S A Esperante
- Protein Structure-Function and Engineering Laboratory, Fundación Instituto Leloir and IIBBA-CONICET, Argentina
| | - M Salgueiro
- Protein Structure-Function and Engineering Laboratory, Fundación Instituto Leloir and IIBBA-CONICET, Argentina
| | - G Camporeale
- Protein Structure-Function and Engineering Laboratory, Fundación Instituto Leloir and IIBBA-CONICET, Argentina
| | - G A P de Oliveira
- Programa de Biologia Estrutural, Instituto de Bioquímica Médica Leopoldo de Meis, Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Centro Nacional de Ressonância Magnêtica Nuclear Jiri Jonas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil and Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908-0733, USA
| | - G Prat Gay
- Protein Structure-Function and Engineering Laboratory, Fundación Instituto Leloir and IIBBA-CONICET, Argentina.
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29
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Tognarelli EI, Bueno SM, González PA. Immune-Modulation by the Human Respiratory Syncytial Virus: Focus on Dendritic Cells. Front Immunol 2019; 10:810. [PMID: 31057543 PMCID: PMC6478035 DOI: 10.3389/fimmu.2019.00810] [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: 12/14/2018] [Accepted: 03/26/2019] [Indexed: 12/23/2022] Open
Abstract
The human respiratory syncytial virus (hRSV) is the leading cause of pneumonia in infants and produces a significant burden in the elderly. It can also infect and produce disease in otherwise healthy adults and recurrently infect those previously exposed to the virus. Importantly, recurrent infections are not necessarily a consequence of antigenic variability, as described for other respiratory viruses, but most likely due to the capacity of this virus to interfere with the host's immune response and the establishment of a protective and long-lasting immunity. Although some genes encoded by hRSV are known to have a direct participation in immune evasion, it seems that repeated infection is mainly given by its capacity to modulate immune components in such a way to promote non-optimal antiviral responses in the host. Importantly, hRSV is known to interfere with dendritic cell (DC) function, which are key cells involved in establishing and regulating protective virus-specific immunity. Notably, hRSV infects DCs, alters their maturation, migration to lymph nodes and their capacity to activate virus-specific T cells, which likely impacts the host antiviral response against this virus. Here, we review and discuss the most important and recent findings related to DC modulation by hRSV, which might be at the basis of recurrent infections in previously infected individuals and hRSV-induced disease. A focus on the interaction between DCs and hRSV will likely contribute to the development of effective prophylactic and antiviral strategies against this virus.
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Affiliation(s)
- Eduardo I Tognarelli
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Susan M Bueno
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A González
- Millennium Institute on Immunology and Immunotherapy, Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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30
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Meshram CD, Oomens AGP. Identification of a human respiratory syncytial virus phosphoprotein domain required for virus-like-particle formation. Virology 2019; 532:48-54. [PMID: 31009855 DOI: 10.1016/j.virol.2019.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 04/03/2019] [Accepted: 04/04/2019] [Indexed: 10/27/2022]
Abstract
Perceived inefficiency and inadequate knowledge of the human respiratory syncytial virus (hRSV) assembly process present a hurdle for large-scale production of authentic hRSV virus-like particles (VLPs) for vaccine purposes. We previously established that the matrix protein, phosphoprotein (P), and fusion protein carboxy-terminus were sufficient to generate VLPs that resemble filamentous wildtype hRSV. Here, the contribution of P was examined. By co-expressing matrix, fusion, and modified P proteins, a ser/thr-rich P region (residues 39-57) was found to be critical for VLP formation, whereas the oligomerization domain was not. Substitutions throughout region 39-57 inhibited VLP formation and relevant amino acids were identified. Phosphomimetic substitutions of serines and threonines inhibited VLP formation; Phosphoblatant substitutions did not. The data show that P not only co-regulates replication and transcription but also has an important role in assembly, mediated by a separate domain that likely interacts with M and/or F and is highly regulated by phosphorylation.
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Affiliation(s)
- Chetan D Meshram
- Department of Microbiology. University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Antonius G P Oomens
- Center for Veterinary Health Sciences, Oklahoma State University, 250 McElroy Hall, Stillwater, OK, 74078, USA.
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31
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Esneau C, Raynal B, Roblin P, Brûlé S, Richard CA, Fix J, Eléouët JF, Galloux M. Biochemical characterization of the respiratory syncytial virus N 0-P complex in solution. J Biol Chem 2019; 294:3647-3660. [PMID: 30626736 PMCID: PMC6416419 DOI: 10.1074/jbc.ra118.006453] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/21/2018] [Indexed: 12/24/2022] Open
Abstract
As all the viruses belonging to the Mononegavirales order, the nonsegmented negative-strand RNA genome of respiratory syncytial virus (RSV) is encapsidated by the viral nucleoprotein N. N protein polymerizes along the genomic and anti-genomic RNAs during replication. This requires the maintenance of the neosynthesized N protein in a monomeric and RNA-free form by the viral phosphoprotein P that plays the role of a chaperone protein, forming a soluble N0-P complex. We have previously demonstrated that residues 1-30 of P specifically bind to N0 Here, to isolate a stable N0-P complex suitable for structural studies, we used the N-terminal peptide of P (P40) to purify truncated forms of the N protein. We show that to purify a stable N0-P-like complex, a deletion of the first 30 N-terminal residues of N (NΔ30) is required to impair N oligomerization, whereas the presence of a full-length C-arm of N is required to inhibit RNA binding. We generated structural models of the RSV N0-P with biophysical approaches, including hydrodynamic measurements and small-angle X-ray scattering (SAXS), coupled with biochemical and functional analyses of human RSV (hRSV) NΔ30 mutants. These models suggest a strong structural homology between the hRSV and the human metapneumovirus (hMPV) N0-P complexes. In both complexes, the P40-binding sites on N0 appear to be similar, and the C-arm of N provides a high flexibility and a propensity to interact with the N RNA groove. These findings reveal two potential sites to target on N0-P for the development of RSV antivirals.
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Affiliation(s)
- Camille Esneau
- From the Untié de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Bertrand Raynal
- Plate-forme de Biophysique Moléculaire, C2RT, Institut Pasteur, 25 Rue du Docteur Roux, 75015 Paris, France
| | - Pierre Roblin
- Synchrotron SOLEIL, L'Orme des Merisiers, F-91410 Saint Aubin, France, and
- Laboratoire de Génie Chimique, Université Paul Sabatier, UMR 5503, Toulouse, France
| | - Sébastien Brûlé
- Plate-forme de Biophysique Moléculaire, C2RT, Institut Pasteur, 25 Rue du Docteur Roux, 75015 Paris, France
| | - Charles-Adrien Richard
- From the Untié de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Jenna Fix
- From the Untié de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, 78350 Jouy-en-Josas, France
| | - Jean-François Eléouët
- From the Untié de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, 78350 Jouy-en-Josas, France,
| | - Marie Galloux
- From the Untié de Virologie et Immunologie Moléculaires, Institut National de la Recherche Agronomique, Université Paris-Saclay, 78350 Jouy-en-Josas, France,
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32
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Richard CA, Hervet C, Ménard D, Gutsche I, Normand V, Renois F, Meurens F, Eléouët JF. First demonstration of the circulation of a pneumovirus in French pigs by detection of anti-swine orthopneumovirus nucleoprotein antibodies. Vet Res 2018; 49:118. [PMID: 30518406 PMCID: PMC6280484 DOI: 10.1186/s13567-018-0615-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 11/29/2018] [Indexed: 12/22/2022] Open
Abstract
The presence of pneumoviruses in pigs is poorly documented. In this study, we used the published sequence of the nucleoprotein (N) of the recently identified Swine Orthopneumovirus (SOV) to express and purify SOV N as a recombinant protein in Escherichia coli. This protein was purified as nanorings and used to set up an enzyme-linked immunosorbent assay, which was used to analyse the presence of anti-pneumovirus N antibodies in swine sera. Sera collected from different pig farms in the West of France and from specific pathogen free piglets before colostrum uptake showed indirectly that a pneumovirus is circulating in pig populations with some variations between animals. Piglets before colostrum uptake were sero-negative for anti-pneumovirus antibodies while most of the other pigs showed positivity. Interestingly, in two farms presenting respiratory clinical signs and negative or under control for some common respiratory pathogens, pigs were detected positive for anti-pneumovirus antibodies. Globally, anti-pneumovirus N antibody concentrations were variable between and within farms. Further studies will aim to isolate the circulating virus and determine its potential pathogenicity. SOV could potentially become a new member of the porcine respiratory complex, important on its own or in association with other viral and bacterial micro-organisms.
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Affiliation(s)
- Charles-Adrien Richard
- Unité de Virologie et Immunologie Moléculaires, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France
| | - Caroline Hervet
- BIOEPAR, INRA, Oniris, Université Bretagne Loire, 44307, Nantes, France
| | - Déborah Ménard
- BIOEPAR, INRA, Oniris, Université Bretagne Loire, 44307, Nantes, France
| | - Irina Gutsche
- CNRS, CEA, IBS, University of Grenoble Alpes, 38000, Grenoble, France
| | - Valérie Normand
- Porc.Spective Swine Vet Practice, Chêne Vert Conseil Veterinary Group, ZA de Gohélève, 56920, Noyal-Pontivy, France
| | - Fanny Renois
- BIOEPAR, INRA, Oniris, Université Bretagne Loire, 44307, Nantes, France
| | - François Meurens
- BIOEPAR, INRA, Oniris, Université Bretagne Loire, 44307, Nantes, France
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
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33
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Selvaraj M, Yegambaram K, Todd EJAA, Richard CA, Dods RL, Pangratiou GM, Trinh CH, Moul SL, Murphy JC, Mankouri J, Éléouët JF, Barr JN, Edwards TA. The Structure of the Human Respiratory Syncytial Virus M2-1 Protein Bound to the Interaction Domain of the Phosphoprotein P Defines the Orientation of the Complex. mBio 2018; 9:e01554-18. [PMID: 30425144 PMCID: PMC6234862 DOI: 10.1128/mbio.01554-18] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 10/02/2018] [Indexed: 01/09/2023] Open
Abstract
Human respiratory syncytial virus (HRSV) is a negative-stranded RNA virus that causes a globally prevalent respiratory infection, which can cause life-threatening illness, particularly in the young, elderly, and immunocompromised. HRSV multiplication depends on replication and transcription of the HRSV genes by the virus-encoded RNA-dependent RNA polymerase (RdRp). For replication, this complex comprises the phosphoprotein (P) and the large protein (L), whereas for transcription, the M2-1 protein is also required. M2-1 is recruited to the RdRp by interaction with P and also interacts with RNA at overlapping binding sites on the M2-1 surface, such that binding of these partners is mutually exclusive. The molecular basis for the transcriptional requirement of M2-1 is unclear, as is the consequence of competition between P and RNA for M2-1 binding, which is likely a critical step in the transcription mechanism. Here, we report the crystal structure at 2.4 Å of M2-1 bound to the P interaction domain, which comprises P residues 90 to 110. The P90-110 peptide is alpha helical, and its position on the surface of M2-1 defines the orientation of the three transcriptase components within the complex. The M2-1/P interface includes ionic, hydrophobic, and hydrogen bond interactions, and the critical contribution of these contacts to complex formation was assessed using a minigenome assay. The affinity of M2-1 for RNA and P ligands was quantified using fluorescence anisotropy, which showed high-affinity RNAs could outcompete P. This has important implications for the mechanism of transcription, particularly the events surrounding transcription termination and synthesis of poly(A) sequences.IMPORTANCE Human respiratory syncytial virus (HRSV) is a leading cause of respiratory illness, particularly in the young, elderly, and immunocompromised, and has also been linked to the development of asthma. HRSV replication depends on P and L, whereas transcription also requires M2-1. M2-1 interacts with P and RNA at overlapping binding sites; while these interactions are necessary for transcriptional activity, the mechanism of M2-1 action is unclear. To better understand HRSV transcription, we solved the crystal structure of M2-1 in complex with the minimal P interaction domain, revealing molecular details of the M2-1/P interface and defining the orientation of M2-1 within the tripartite complex. The M2-1/P interaction is relatively weak, suggesting high-affinity RNAs may displace M2-1 from the complex, providing the basis for a new model describing the role of M2-1 in transcription. Recently, the small molecules quercetin and cyclopamine have been used to validate M2-1 as a drug target.
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Affiliation(s)
- Muniyandi Selvaraj
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Kavestri Yegambaram
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Eleanor J A A Todd
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Charles-Adrien Richard
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Rachel L Dods
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Georgia M Pangratiou
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Chi H Trinh
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Sophie L Moul
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - James C Murphy
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Jamel Mankouri
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Jean-François Éléouët
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - John N Barr
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Thomas A Edwards
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
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34
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Milles S, Jensen MR, Lazert C, Guseva S, Ivashchenko S, Communie G, Maurin D, Gerlier D, Ruigrok RWH, Blackledge M. An ultraweak interaction in the intrinsically disordered replication machinery is essential for measles virus function. SCIENCE ADVANCES 2018; 4:eaat7778. [PMID: 30140745 PMCID: PMC6105297 DOI: 10.1126/sciadv.aat7778] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 07/18/2018] [Indexed: 05/05/2023]
Abstract
Measles virus genome encapsidation is essential for viral replication and is controlled by the intrinsically disordered phosphoprotein (P) maintaining the nucleoprotein in a monomeric form (N) before nucleocapsid assembly. All paramyxoviruses harbor highly disordered amino-terminal domains (PNTD) that are hundreds of amino acids in length and whose function remains unknown. Using nuclear magnetic resonance (NMR) spectroscopy, we describe the structure and dynamics of the 90-kDa N0PNTD complex, comprising 450 disordered amino acids, at atomic resolution. NMR relaxation dispersion reveals the existence of an ultraweak N-interaction motif, hidden within the highly disordered PNTD, that allows PNTD to rapidly associate and dissociate from a specific site on N while tightly bound at the amino terminus, thereby hindering access to the surface of N. Mutation of this linear motif quenches the long-range dynamic coupling between the two interaction sites and completely abolishes viral transcription/replication in cell-based minigenome assays comprising integral viral replication machinery. This description transforms our understanding of intrinsic conformational disorder in paramyxoviral replication. The essential mechanism appears to be conserved across Paramyxoviridae, opening unique new perspectives for drug development against this family of pathogens.
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Affiliation(s)
- Sigrid Milles
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Malene Ringkjøbing Jensen
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Carine Lazert
- International Center for Infectiology Research, INSERM, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, Lyon, France
| | - Serafima Guseva
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Stefaniia Ivashchenko
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Guillaume Communie
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Damien Maurin
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Denis Gerlier
- International Center for Infectiology Research, INSERM, U1111, Université Claude Bernard Lyon 1, CNRS, UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, Lyon, France
| | - Rob W. H. Ruigrok
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
| | - Martin Blackledge
- Université Grenoble Alpes, CNRS, Commissariat à l’Energie Atomique et aux Energies Alternatives, Institut de Biologie Structurale, 38000 Grenoble, France
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Richard CA, Rincheval V, Lassoued S, Fix J, Cardone C, Esneau C, Nekhai S, Galloux M, Rameix-Welti MA, Sizun C, Eléouët JF. RSV hijacks cellular protein phosphatase 1 to regulate M2-1 phosphorylation and viral transcription. PLoS Pathog 2018; 14:e1006920. [PMID: 29489893 PMCID: PMC5847313 DOI: 10.1371/journal.ppat.1006920] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 03/12/2018] [Accepted: 02/04/2018] [Indexed: 12/31/2022] Open
Abstract
Respiratory syncytial virus (RSV) RNA synthesis occurs in cytoplasmic inclusion bodies (IBs) in which all the components of the viral RNA polymerase are concentrated. In this work, we show that RSV P protein recruits the essential RSV transcription factor M2-1 to IBs independently of the phosphorylation state of M2-1. We also show that M2-1 dephosphorylation is achieved by a complex formed between P and the cellular phosphatase PP1. We identified the PP1 binding site of P, which is an RVxF-like motif located nearby and upstream of the M2-1 binding region. NMR confirmed both P-M2-1 and P-PP1 interaction regions in P. When the P-PP1 interaction was disrupted, M2-1 remained phosphorylated and viral transcription was impaired, showing that M2-1 dephosphorylation is required, in a cyclic manner, for efficient viral transcription. IBs contain substructures called inclusion bodies associated granules (IBAGs), where M2-1 and neo-synthesized viral mRNAs concentrate. Disruption of the P-PP1 interaction was correlated with M2-1 exclusion from IBAGs, indicating that only dephosphorylated M2-1 is competent for viral mRNA binding and hence for a previously proposed post-transcriptional function.
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Affiliation(s)
- Charles-Adrien Richard
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Vincent Rincheval
- UMR1173, INSERM, Université de Versailles St. Quentin, Montigny le Bretonneux, France
| | - Safa Lassoued
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Jenna Fix
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Christophe Cardone
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Camille Esneau
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Sergei Nekhai
- Center for Sickle Cell Disease and Department of Medicine, Howard University, Washington, D. C., United States of America
| | - Marie Galloux
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
| | - Marie-Anne Rameix-Welti
- UMR1173, INSERM, Université de Versailles St. Quentin, Montigny le Bretonneux, France
- AP-HP, Laboratoire de Microbiologie, Hôpital Ambroise Paré, Boulogne-Billancourt, France
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris-Saclay, Avenue de la Terrasse, Gif-sur-Yvette, France
| | - Jean-François Eléouët
- Unité de Virologie et Immunologie Moléculaires (UR892), INRA, Université Paris-Saclay, Jouy-en-Josas, France
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36
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Jordan PC, Stevens SK, Deval J. Nucleosides for the treatment of respiratory RNA virus infections. Antivir Chem Chemother 2018; 26:2040206618764483. [PMID: 29562753 PMCID: PMC5890544 DOI: 10.1177/2040206618764483] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/07/2018] [Indexed: 12/20/2022] Open
Abstract
Influenza virus, respiratory syncytial virus, human metapneumovirus, parainfluenza virus, coronaviruses, and rhinoviruses are among the most common viruses causing mild seasonal colds. These RNA viruses can also cause lower respiratory tract infections leading to bronchiolitis and pneumonia. Young children, the elderly, and patients with compromised cardiac, pulmonary, or immune systems are at greatest risk for serious disease associated with these RNA virus respiratory infections. In addition, swine and avian influenza viruses, together with severe acute respiratory syndrome-associated and Middle Eastern respiratory syndrome coronaviruses, represent significant pandemic threats to the general population. In this review, we describe the current medical need resulting from respiratory infections caused by RNA viruses, which justifies drug discovery efforts to identify new therapeutic agents. The RNA polymerase of respiratory viruses represents an attractive target for nucleoside and nucleotide analogs acting as inhibitors of RNA chain synthesis. Here, we present the molecular, biochemical, and structural fundamentals of the polymerase of the four major families of RNA respiratory viruses: Orthomyxoviridae, Pneumoviridae/Paramyxoviridae, Coronaviridae, and Picornaviridae. We summarize past and current efforts to develop nucleoside and nucleotide analogs as antiviral agents against respiratory virus infections. This includes molecules with very broad antiviral spectrum such as ribavirin and T-705 (favipiravir), and others targeting more specifically one or a few virus families. Recent advances in our understanding of the structure(s) and function(s) of respiratory virus polymerases will likely support the discovery and development of novel nucleoside analogs.
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Affiliation(s)
- Paul C Jordan
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
| | - Sarah K Stevens
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
| | - Jerome Deval
- Alios BioPharma, Inc., a Janssen Pharmaceutical Company of Johnson & Johnson, South San Francisco, USA
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37
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Structural dissection of human metapneumovirus phosphoprotein using small angle x-ray scattering. Sci Rep 2017; 7:14865. [PMID: 29093501 PMCID: PMC5665942 DOI: 10.1038/s41598-017-14448-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 10/10/2017] [Indexed: 12/21/2022] Open
Abstract
The phosphoprotein (P) is the main and essential cofactor of the RNA polymerase (L) of non-segmented, negative‐strand RNA viruses. P positions the viral polymerase onto its nucleoprotein–RNA template and acts as a chaperone of the nucleoprotein (N), thereby preventing nonspecific encapsidation of cellular RNAs. The phosphoprotein of human metapneumovirus (HMPV) forms homotetramers composed of a stable oligomerization domain (Pcore) flanked by large intrinsically disordered regions (IDRs). Here we combined x-ray crystallography of Pcore with small angle x-ray scattering (SAXS)-based ensemble modeling of the full-length P protein and several of its fragments to provide a structural description of P that captures its dynamic character, and highlights the presence of varyingly stable structural elements within the IDRs. We discuss the implications of the structural properties of HMPV P for the assembly and functioning of the viral transcription/replication machinery.
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38
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Longhi S, Bloyet LM, Gianni S, Gerlier D. How order and disorder within paramyxoviral nucleoproteins and phosphoproteins orchestrate the molecular interplay of transcription and replication. Cell Mol Life Sci 2017; 74:3091-3118. [PMID: 28600653 PMCID: PMC11107670 DOI: 10.1007/s00018-017-2556-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 06/01/2017] [Indexed: 01/01/2023]
Abstract
In this review, we summarize computational and experimental data gathered so far showing that structural disorder is abundant within paramyxoviral nucleoproteins (N) and phosphoproteins (P). In particular, we focus on measles, Nipah, and Hendra viruses and highlight both commonalities and differences with respect to the closely related Sendai virus. The molecular mechanisms that control the disorder-to-order transition undergone by the intrinsically disordered C-terminal domain (NTAIL) of their N proteins upon binding to the C-terminal X domain (XD) of the homologous P proteins are described in detail. By having a significant residual disorder, NTAIL-XD complexes are illustrative examples of "fuzziness", whose possible functional significance is discussed. Finally, the relevance of N-P interactions as promising targets for innovative antiviral approaches is underscored, and the functional advantages of structural disorder for paramyxoviruses are pinpointed.
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Affiliation(s)
- Sonia Longhi
- Aix-Marseille Univ, AFMB UMR 7257, 163, avenue de Luminy, Case 932, 13288, Marseille Cedex 09, France.
- CNRS, AFMB UMR 7257, 13288, Marseille, France.
| | - Louis-Marie Bloyet
- CIRI, International Center for Infectiology Research, Université de Lyon, Lyon, France
- INSERM, U1111, Lyon, France
- Ecole Normale Supérieure de Lyon, Lyon, France
- Université Claude Bernard Lyon 1, Centre International de Recherche en Infectiologie, Lyon, France
- CNRS, UMR5308, Lyon, France
| | - Stefano Gianni
- Istituto Pasteur, Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, 00185, Rome, Italy
| | - Denis Gerlier
- CIRI, International Center for Infectiology Research, Université de Lyon, Lyon, France
- INSERM, U1111, Lyon, France
- Ecole Normale Supérieure de Lyon, Lyon, France
- Université Claude Bernard Lyon 1, Centre International de Recherche en Infectiologie, Lyon, France
- CNRS, UMR5308, Lyon, France
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