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Kanakala S, Xavier CAD, Martin KM, Tran HH, Redinbaugh MG, Whitfield AE. Rescue of the first alphanucleorhabdovirus entirely from cloned complementary DNA: An efficient vector for systemic expression of foreign genes in maize and insect vectors. MOLECULAR PLANT PATHOLOGY 2023; 24:788-800. [PMID: 36239302 DOI: 10.1111/mpp.13273] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 09/07/2022] [Accepted: 09/08/2022] [Indexed: 06/11/2023]
Abstract
Recent reverse genetics technologies have enabled genetic manipulation of plant negative-strand RNA virus (NSR) genomes. Here, we report construction of an infectious clone for the maize-infecting Alphanucleorhabdovirus maydis, the first efficient NSR vector for maize. The full-length infectious clone was established using agrobacterium-mediated delivery of full-length maize mosaic virus (MMV) antigenomic RNA and the viral core proteins (nucleoprotein N, phosphoprotein P, and RNA-directed RNA polymerase L) required for viral transcription and replication into Nicotiana benthamiana. Insertion of intron 2 ST-LS1 into the viral L gene increased stability of the infectious clone in Escherichia coli and Agrobacterium tumefaciens. To monitor virus infection in vivo, a green fluorescent protein (GFP) gene was inserted in between the N and P gene junctions to generate recombinant MMV-GFP. Complementary DNA (cDNA) clones of MMV-wild type (WT) and MMV-GFP replicated in single cells of agroinfiltrated N. benthamiana. Uniform systemic infection and high GFP expression were observed in maize inoculated with extracts of the infiltrated N. benthamiana leaves. Insect vectors supported virus infection when inoculated via feeding on infected maize or microinjection. Both MMV-WT and MMV-GFP were efficiently transmitted to maize by planthopper vectors. The GFP reporter gene was stable in the virus genome and expression remained high over three cycles of transmission in plants and insects. The MMV infectious clone will be a versatile tool for expression of proteins of interest in maize and cross-kingdom studies of virus replication in plant and insect hosts.
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Affiliation(s)
- Surapathrudu Kanakala
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, USA
| | - César A D Xavier
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, USA
| | - Kathleen M Martin
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, USA
| | - Hong Hanh Tran
- Department of Plant Pathology, The Ohio State University, Wooster, Ohio, USA
| | | | - Anna E Whitfield
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, North Carolina, USA
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2
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Jenni S, Horwitz JA, Bloyet LM, Whelan SPJ, Harrison SC. Visualizing molecular interactions that determine assembly of a bullet-shaped vesicular stomatitis virus particle. Nat Commun 2022; 13:4802. [PMID: 35970826 PMCID: PMC9378655 DOI: 10.1038/s41467-022-32223-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 07/18/2022] [Indexed: 11/09/2022] Open
Abstract
Vesicular stomatitis virus (VSV) is a negative-strand RNA virus with a non-segmented genome, closely related to rabies virus. Both have characteristic bullet-like shapes. We report the structure of intact, infectious VSV particles determined by cryogenic electron microscopy. By compensating for polymorphism among viral particles with computational classification, we obtained a reconstruction of the shaft ("trunk") at 3.5 Å resolution, with lower resolution for the rounded tip. The ribonucleoprotein (RNP), genomic RNA complexed with nucleoprotein (N), curls into a dome-like structure with about eight gradually expanding turns before transitioning into the regular helical trunk. Two layers of matrix (M) protein link the RNP with the membrane. Radial inter-layer subunit contacts are fixed within single RNA-N-M1-M2 modules, but flexible lateral and axial interactions allow assembly of polymorphic virions. Together with published structures of recombinant N in various states, our results suggest a mechanism for membrane-coupled self-assembly of VSV and its relatives.
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Affiliation(s)
- Simon Jenni
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA.
| | - Joshua A Horwitz
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA.,Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA.,Molecular Pharmacology and Virology Group, PureTech Health LLC, Boston, MA, 02210, USA
| | - Louis-Marie Bloyet
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA.,Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Sean P J Whelan
- Department of Microbiology, Harvard Medical School, Boston, MA, 02115, USA.,Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA. .,Howard Hughes Medical Institute, Harvard Medical School, Boston, MA, 02115, USA. .,Laboratory of Molecular Medicine, Boston Children's Hospital, Boston, MA, 02115, USA.
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3
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Nath B, Morla S, Kumar S. Reverse Genetics and Its Usage in the Development of Vaccine Against Poultry Diseases. Methods Mol Biol 2022; 2411:77-92. [PMID: 34816399 DOI: 10.1007/978-1-0716-1888-2_4] [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: 06/13/2023]
Abstract
Vaccines are the most effective and economic way of combating poultry viruses. However, the use of traditional live-attenuated poultry vaccines has problems such as antigenic differences with the currently circulating strains of viruses and the risk of reversion to virulence. In veterinary medicine, reverse genetics is applied to solve these problems by developing genotype-matched vaccines, better attenuated and effective live vaccines, broad-spectrum vaccine vectors, bivalent vaccines, and genetically tagged recombinant vaccines that facilitate the serological differentiation of vaccinated animals from infected animals. In this chapter, we discuss reverse genetics as a tool for the development of recombinant vaccines against economically devastating poultry viruses.
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Affiliation(s)
- Barnali Nath
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Sudhir Morla
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Sachin Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, India.
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4
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Jackson AO, Li Z. Developments in Plant Negative-Strand RNA Virus Reverse Genetics. ANNUAL REVIEW OF PHYTOPATHOLOGY 2016; 54:469-498. [PMID: 27359368 DOI: 10.1146/annurev-phyto-080615-095909] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Twenty years ago, breakthroughs for reverse genetics analyses of negative-strand RNA (NSR) viruses were achieved by devising conditions for generation of infectious viruses in susceptible cells. Recombinant strategies have subsequently been engineered for members of all vertebrate NSR virus families, and research arising from these advances has profoundly increased understanding of infection cycles, pathogenesis, and complexities of host interactions of animal NSR viruses. These strategies also permitted development of many applications, including attenuated vaccines and delivery vehicles for therapeutic and biotechnology proteins. However, for a variety of reasons, it was difficult to devise procedures for reverse genetics analyses of plant NSR viruses. In this review, we discuss advances that have circumvented these problems and resulted in construction of a recombinant system for Sonchus yellow net nucleorhabdovirus. We also discuss possible extensions to other plant NSR viruses as well as the applications that may emanate from recombinant analyses of these pathogens.
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Affiliation(s)
- Andrew O Jackson
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720;
| | - Zhenghe Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058 China;
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Ganesan U, Bragg JN, Deng M, Marr S, Lee MY, Qian S, Shi M, Kappel J, Peters C, Lee Y, Goodin MM, Dietzgen RG, Li Z, Jackson AO. Construction of a Sonchus Yellow Net Virus minireplicon: a step toward reverse genetic analysis of plant negative-strand RNA viruses. J Virol 2013; 87:10598-611. [PMID: 23885070 PMCID: PMC3807423 DOI: 10.1128/jvi.01397-13] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 07/15/2013] [Indexed: 12/31/2022] Open
Abstract
Reverse genetic analyses of negative-strand RNA (NSR) viruses have provided enormous advances in our understanding of animal viruses over the past 20 years, but technical difficulties have hampered application to plant NSR viruses. To develop a reverse genetic approach for analysis of plant NSR viruses, we have engineered Sonchus yellow net nucleorhabdovirus (SYNV) minireplicon (MR) reporter cassettes for Agrobacterium tumefaciens expression in Nicotiana benthamiana leaves. Fluorescent reporter genes substituted for the SYNV N and P protein open reading frames (ORFs) exhibited intense single-cell foci throughout regions of infiltrated leaves expressing the SYNV MR derivatives and the SYNV nucleocapsid (N), phosphoprotein (P), and polymerase (L) proteins. Genomic RNA and mRNA transcription was detected for reporter genes substituted for both the SYNV N and P ORFs. These activities required expression of the N, P, and L core proteins in trans and were enhanced by codelivery of viral suppressor proteins that interfere with host RNA silencing. As is the case with other members of the Mononegavirales, we detected polar expression of fluorescent proteins and chloramphenicol acetyltransferase substitutions for the N and P protein ORFs. We also demonstrated the utility of the SYNV MR system for functional analysis of SYNV core proteins in trans and the cis-acting leader and trailer sequence requirements for transcription and replication. This work provides a platform for construction of more complex SYNV reverse genetic derivatives and presents a general strategy for reverse genetic applications with other plant NSR viruses.
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Affiliation(s)
- Uma Ganesan
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Jennifer N. Bragg
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Min Deng
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Sharon Marr
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Mi Yeon Lee
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - ShaSha Qian
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Manling Shi
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
- School of Life and Environmental Science, Hangzhou Normal University, Xiashi High Education Zone, Hangzhou, China
| | - Justin Kappel
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Cole Peters
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Yeon Lee
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - Michael M. Goodin
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
- Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, USA
| | - Ralf G. Dietzgen
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, Australia
| | - Zhenghe Li
- State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China
| | - Andrew O. Jackson
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
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Abstract
The antiquated system used to manufacture the currently licensed inactivated influenza virus vaccines would not be adequate during an influenza virus pandemic. There is currently a search for vaccines that can be developed faster and provide superior, long-lasting immunity to influenza virus as well as other highly pathogenic viruses and bacteria. Recombinant vectors provide a safe and effective method to elicit a strong immune response to a foreign protein or epitope. This review explores the advantages and limitations of several different vectors that are currently being tested, and highlights some of the newer viruses being used as recombinant vectors.
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Billeter MA, Naim HY, Udem SA. Reverse genetics of measles virus and resulting multivalent recombinant vaccines: applications of recombinant measles viruses. Curr Top Microbiol Immunol 2009; 329:129-62. [PMID: 19198565 PMCID: PMC7120638 DOI: 10.1007/978-3-540-70523-9_7] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An overview is given on the development of technologies to allow reverse genetics of RNA viruses, i.e., the rescue of viruses from cDNA, with emphasis on nonsegmented negative-strand RNA viruses ( Mononegavirales ), as exemplified for measles virus (MV). Primarily, these technologies allowed site-directed mutagenesis, enabling important insights into a variety of aspects of the biology of these viruses. Concomitantly, foreign coding sequences were inserted to (a) allow localization of virus replication in vivo through marker gene expression, (b) develop candidate multivalent vaccines against measles and other pathogens, and (c) create candidate oncolytic viruses. The vector use of these viruses was experimentally encouraged by the pronounced genetic stability of the recombinants unexpected for RNA viruses, and by the high load of insertable genetic material, in excess of 6 kb. The known assets, such as the small genome size of the vector in comparison to DNA viruses proposed as vectors, the extensive clinical experience of attenuated MV as vaccine with a proven record of high safety and efficacy, and the low production cost per vaccination dose are thus favorably complemented.
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Affiliation(s)
- M A Billeter
- University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
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Roberts A, Reuter JD, Wilson JH, Baldwin S, Rose JK. Complete protection from papillomavirus challenge after a single vaccination with a vesicular stomatitis virus vector expressing high levels of L1 protein. J Virol 2004; 78:3196-9. [PMID: 14990742 PMCID: PMC353748 DOI: 10.1128/jvi.78.6.3196-3199.2004] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We generated an attenuated, recombinant vesicular stomatitis virus (VSV) expressing high levels of the cottontail rabbit papillomavirus (CRPV) L1 protein from an upstream site in the VSV genome. Rabbits vaccinated once with this VSV-L1 recombinant produced high levels of anti-L1 antibody and were completely protected against papilloma formation after challenge with CRPV. In contrast, animals vaccinated only once with a VSV vector expressing lower levels of L1 from a downstream site in the VSV genome generated lower levels of L1 antibody and demonstrated only incomplete protection from papilloma formation after challenge. We conclude that the level of L1 protein expression is critical in generating complete immunity with a single-dose vaccine.
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Affiliation(s)
- Anjeanette Roberts
- Department of Pathology. Section of Comparative Medicine, Yale University School of Medicine, New Haven, Connecticut 06510
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Abstract
"Reverse genetics" or de novo synthesis of nonsegmented negative-sense RNA viruses (Mononegavirales) from cloned cDNA has become a reliable technique to study this group of medically important viruses. Since the first generation of a negative-sense RNA virus entirely from cDNA in 1994, reverse genetics systems have been established for members of most genera of the Rhabdo-, Paramyxo-, and Filoviridae families. These systems are based on intracellular transcription of viral full-length RNAs and simultaneous expression of viral proteins required to form the typical viral ribonucleoprotein complex (RNP). These systems are powerful tools to study all aspects of the virus life cycle as well as the roles of virus proteins in virus-host interplay and pathogenicity. In addition, recombinant viruses can be designed to have specific properties that make them attractive as biotechnological tools and live vaccines.
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Affiliation(s)
- K K Conzelmann
- Max von Pettenkofer-Institut and Genzentrum, Ludwig-Maximilians-Universität München, Munich, Germany.
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10
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Abstract
Avian influenza viruses are major contributors to viral disease in poultry as well as humans. Outbreaks of high-pathogenicity avian influenza viruses cause high mortality in poultry, resulting in significant economic losses. The potential of avian influenza viruses to reassort with human stains resulted in global pandemics in 1957 and 1968, while the introduction of an entirely avian virus into humans claimed several lives in Hong Kong in 1997. Despite considerable research, the mechanisms that determine the pathogenic potential of a virus or its ability to cross the species barrier are poorly understood. Reverse genetics methods, i.e., methods that allow the generation of an influenza virus entirely from cloned cDNAs, have provided us with one means to address these issues. In addition, reverse genetics is an excellent tool for vaccine production and development. This technology should increase our preparedness for future influenza virus outbreaks.
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Affiliation(s)
- G Neumann
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive West, Madison, WI 53706, USA
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Neumann G, Whitt MA, Kawaoka Y. A decade after the generation of a negative-sense RNA virus from cloned cDNA - what have we learned? J Gen Virol 2002; 83:2635-2662. [PMID: 12388800 DOI: 10.1099/0022-1317-83-11-2635] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Since the first generation of a negative-sense RNA virus entirely from cloned cDNA in 1994, similar reverse genetics systems have been established for members of most genera of the Rhabdo- and Paramyxoviridae families, as well as for Ebola virus (Filoviridae). The generation of segmented negative-sense RNA viruses was technically more challenging and has lagged behind the recovery of nonsegmented viruses, primarily because of the difficulty of providing more than one genomic RNA segment. A member of the Bunyaviridae family (whose genome is composed of three RNA segments) was first generated from cloned cDNA in 1996, followed in 1999 by the production of influenza virus, which contains eight RNA segments. Thus, reverse genetics, or the de novo synthesis of negative-sense RNA viruses from cloned cDNA, has become a reliable laboratory method that can be used to study this large group of medically and economically important viruses. It provides a powerful tool for dissecting the virus life cycle, virus assembly, the role of viral proteins in pathogenicity and the interplay of viral proteins with components of the host cell immune response. Finally, reverse genetics has opened the way to develop live attenuated virus vaccines and vaccine vectors.
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Affiliation(s)
- Gabriele Neumann
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, 2015 Linden Drive West, Madison, WI 53706, USA1
| | - Michael A Whitt
- Department of Molecular Sciences, University of Tennessee Health Science Center, Memphis, TN, USA2
| | - Yoshihiro Kawaoka
- CREST, Japan Science and Technology Corporation, Japan4
- Institute of Medical Science, University of Tokyo, Tokyo, Japan3
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, 2015 Linden Drive West, Madison, WI 53706, USA1
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van den Pol AN, Dalton KP, Rose JK. Relative neurotropism of a recombinant rhabdovirus expressing a green fluorescent envelope glycoprotein. J Virol 2002; 76:1309-27. [PMID: 11773406 PMCID: PMC135838 DOI: 10.1128/jvi.76.3.1309-1327.2002] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A new recombinant vesicular stomatitis virus (rVSV) that expresses green fluorescent protein (GFP) on the cytoplasmic domain of the VSV glycoprotein (G protein) was used in the mouse as a model for studying brain infections by a member of the Mononegavirales order that can cause permanent changes in behavior. After nasal administration, virus moved down the olfactory nerve, first to periglomerular cells, then past the mitral cell layer to granule cells, and finally to the subventricular zone. Eight days postinoculation, rVSV was eliminated from the olfactory bulb. Little sign of infection could be found outside the olfactory system, suggesting that anterograde or retrograde axonal transport of rVSV was an unlikely mechanism for movement of rVSV out of the bulb. When administered intracerebrally by microinjection, rVSV spread rapidly within the brain, with strong infection at the site of injection and at some specific periventricular regions of the brain, including the dorsal raphe, locus coeruleus, and midline thalamus; the ventricular system may play a key role in rapid rVSV dispersion within the brain. Thus, the lack of VSV movement out of the olfactory system was not due to the absence of potential for infections in other brain regions. In cultures of both mouse and human central nervous system (CNS) cells, rVSV inoculations resulted in productive infection, expression of the G-GFP fusion protein in the dendritic and somatic plasma membrane, and death of all neurons and glia, as detected by ethidium homodimer nuclear staining. Although considered a neurotropic virus, rVSV also infected heart, skin, and kidney cells in dispersed cultures. rVSV showed a preference for immature neurons in vitro, as shown by enhanced viral infection in developing hippocampal cultures and in the outer granule cell layer in slices of developing cerebellum. Together, these data suggest a relative affinity of rVSV for some neuronal types in the CNS, adding to our understanding of the long-lasting changes in rodent behavior found after transient VSV infection.
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Affiliation(s)
- Anthony N van den Pol
- Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
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Neumann G, Feldmann H, Watanabe S, Lukashevich I, Kawaoka Y. Reverse genetics demonstrates that proteolytic processing of the Ebola virus glycoprotein is not essential for replication in cell culture. J Virol 2002; 76:406-10. [PMID: 11739705 PMCID: PMC135697 DOI: 10.1128/jvi.76.1.406-410.2002] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2001] [Accepted: 09/20/2001] [Indexed: 01/12/2023] Open
Abstract
Ebola virus, a prime example of an emerging pathogen, causes fatal hemorrhagic fever in humans and in nonhuman primates. Identification of major determinants of Ebola virus pathogenicity has been hampered by the lack of effective strategies for experimental mutagenesis. Here we exploit a reverse genetics system that allows the generation of Ebola virus from cloned cDNA to engineer a mutant Ebola virus with an altered furin recognition motif in the glycoprotein (GP). When expressed in cells, the GP of the wild type, but not of the mutant, virus was cleaved into GP1 and GP2. Although posttranslational furin-mediated cleavage of GP was thought to be an essential step in Ebola virus infection, generation of a viable mutant Ebola virus lacking a furin recognition motif in the GP cleavage site demonstrates that GP cleavage is not essential for replication of Ebola virus in cell culture.
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Affiliation(s)
- Gabriele Neumann
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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