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Brink LR, Chichlowski M, Pastor N, Thimmasandra Narayanappa A, Shah N. In the Age of Viral Pandemic, Can Ingredients Inspired by Human Milk and Infant Nutrition Be Repurposed to Support the Immune System? Nutrients 2021; 13:870. [PMID: 33800961 PMCID: PMC7999376 DOI: 10.3390/nu13030870] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 12/14/2022] Open
Abstract
In 2020, with the advent of a pandemic touching all aspects of global life, there is a renewed interest in nutrition solutions to support the immune system. Infants are vulnerable to infection and breastfeeding has been demonstrated to provide protection. As such, human milk is a great model for sources of functional nutrition ingredients, which may play direct roles in protection against viral diseases. This review aims to summarize the literature around human milk (lactoferrin, milk fat globule membrane, osteopontin, glycerol monolaurate and human milk oligosaccharides) and infant nutrition (polyunsaturated fatty acids, probiotics and postbiotics) inspired ingredients for support against viral infections and the immune system more broadly. We believe that the application of these ingredients can span across all life stages and thus apply to both pediatric and adult nutrition. We highlight the opportunities for further research in this field to help provide tangible nutrition solutions to support one's immune system and fight against infections.
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Affiliation(s)
- Lauren R. Brink
- Medical and Scientific Affairs, Nutrition, Reckitt Benckiser, Evansville, IN 47721, USA; (M.C.); (N.P.)
| | - Maciej Chichlowski
- Medical and Scientific Affairs, Nutrition, Reckitt Benckiser, Evansville, IN 47721, USA; (M.C.); (N.P.)
| | - Nitida Pastor
- Medical and Scientific Affairs, Nutrition, Reckitt Benckiser, Evansville, IN 47721, USA; (M.C.); (N.P.)
| | | | - Neil Shah
- Medical and Scientific Affairs, Nutrition, Reckitt Benckiser, Slough SL1 3UH, UK;
- University College London, Great Ormond Street, London WC1N 3JH, UK
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2
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Beards G. Rotavirus. WIKIJOURNAL OF MEDICINE 2017. [DOI: 10.15347/wjm/2017.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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3
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Cheng W. The Density Code for the Development of a Vaccine? J Pharm Sci 2016; 105:3223-3232. [PMID: 27649885 PMCID: PMC5102155 DOI: 10.1016/j.xphs.2016.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 07/17/2016] [Accepted: 07/26/2016] [Indexed: 10/21/2022]
Abstract
The development of prophylactic vaccines remains largely empirical in nature and rarely have general rules been applied in the strategic decision and the formulation of a viral vaccine. Currently, there are a total of 15 virus agents from 12 unique virus families with vaccines licensed by the U.S. Food and Drug Administration. Extensive structural information on these viral particles and potential mechanisms of protection are available for the majority of these virus pathogens and their respective vaccines. Here I review the quantitative features of these viral surface antigens in relation to the molecular mechanisms of B-cell activation and point out a potential correlation between the density of immunogenic proteins displayed on the surface of the vaccine antigen carrier and the success of a vaccine. These features help us understand the humoral immunity induced by viral vaccines on a quantitative ground and re-emphasize the importance of antigen density on the activation of the immune system. Although the detailed mechanisms behind this phenomenon remain to be explored, it implies that both the size of antigen carriers and the density of immunogenic proteins displayed on these carriers are important parameters that may need to be optimized for the formulation of a vaccine.
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Affiliation(s)
- Wei Cheng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109; Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109; Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109.
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4
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Rahimi A, Varano AC, Demmert AC, Melanson LA, McDonald SM, Kelly DF. A Non-Symmetric Reconstruction Technique for Transcriptionally-Active Viral Assemblies. ACTA ACUST UNITED AC 2015; 2. [PMID: 27819069 PMCID: PMC5094455 DOI: 10.13188/2474-1914.1000004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The molecular mechanisms by which RNA viruses coordinate their transcriptional activities are not fully understood. For rotavirus, an important pediatric gastroenteric pathogen, transcription occurs within a double-layered particle that encloses the viral genome. To date, there remains very little structural information available for actively-transcribing rotavirus double-layered particles, which could provide new insights for antiviral development. To improve our vision of these viral assemblies, we developed a new combinatorial strategy that utilizes currently available high-resolution image processing tools. First, we employed a 3D classification routine that allowed us to sort transcriptionally-active rotavirus assemblies on the basis of their internal density. Next, we implemented an additional 3D refinement procedure using the most active class of DLPs. For comparison, the refined structures were computed in parallel by (1) enforcing icosahedral symmetry, and by (2) using no symmetry operators. Comparing the resulting structures, we were able to visualize the continuum that exists between viral capsid proteins and the viral RNA for the first time.
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Affiliation(s)
- Amina Rahimi
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA
| | | | - Andrew C Demmert
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
| | | | - Sarah M McDonald
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA; Department of Biomedical Sciences and Pathology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, VA, USA
| | - Deborah F Kelly
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA; Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
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5
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Teng Y, Zhao B, Pan X, Wen Y, Chen Y. A new rotavirus VP6-based foreign epitope presenting vector and immunoreactivity of VP4 epitope chimeric proteins. Viral Immunol 2014; 27:96-104. [PMID: 24702286 PMCID: PMC3994975 DOI: 10.1089/vim.2013.0110] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The VP6, the group antigenic rotavirus (RV), is highly conserved and the most abundant, constituting about 39% of the viral structure proteins by weight. The high degree of identity (>87%-99%) in the primary amino acid sequences suggests VP6-based vaccines could potentially provide heterotypic protection. Although some efforts have been made toward producing recombinant rotavirus VP6 vaccines, the native VP6 is still unsatisfactory as an optimal vaccine. The major neutralizing antigenic epitopes that exist on VP4 or VP7 are not on the native VP6, and as a vector the native VP6 lacks insertion sites that can be used for insertion of foreign epitopes. In this study, a new foreign epitope presenting system using VP6 as a vector (VP6F) was constructed on the outer surface of the vector six sites that could be used for insertion of the foreign epitopes created. Using this system, three VP6-based VP4 epitope chimeric proteins were constructed. Results showed that these chimeric proteins reacted with anti-VP6 and -VP4 antibodies, and elicited antibodies against VP6 and VP4 in guinea pigs. Antibodies against VP6F or antibodies against the chimeric proteins neutralized RV Wa and SA11 infection in vitro. It is optimistic that the limitation for using the native VP6 as a vaccine candidate or vector will be solved with our proposed approach. It is expected that this VP6-based epitope presenting system and the VP6-based VP4 epitope chimeric proteins will be valuable for and contribute to the development of novel RV vaccines and vaccine vectors.
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Affiliation(s)
- Yumei Teng
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Bingxin Zhao
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Xiaoxia Pan
- Key Laboratory of Chemistry in Ethnic Medicinal Resources, State Ethnic Affairs Commission and Ministry of Education, Yunnan University of Nationalities, Kunming, China
| | - Yuling Wen
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
| | - Yuanding Chen
- Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, China
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6
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Xie Z, Fan Q, Liu J, Pang Y, Deng X, Xie Z, Liji X, Khan MI. Reverse transcription loop-mediated isothermal amplification assay for rapid detection of Bovine Rotavirus. BMC Vet Res 2012; 8:133. [PMID: 22894568 PMCID: PMC3599620 DOI: 10.1186/1746-6148-8-133] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 06/29/2012] [Indexed: 11/27/2022] Open
Abstract
Background Bovine rotavirus (BRV) infection is common in young calves. This viral infection causes acute diarrhea leading to death. Rapid identification of infected calves is essential to control BRV successfully. Therefore development of simple, highly specific, and sensitive detection method for BRV is needed. Results A reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed and optimized for rapid detection of BRV. Specific primer sets were designed to target the sequences of the VP6 gene of the neonatal calf diarrhea virus (NCDV) strain of BRV. The RT-LAMP assay was performed in a water bath for 60 minutes at 63°C, and the amplification products were visualized either directly or under ultraviolet light. This BRV specific RT-LAMP assay could detect 3.32 copies of subtype A BRV. No cross-reactions were detected with other bovine pathogens. The ability of RT-LAMP to detect bovine rotavirus was further evaluated with 88 bovine rectal swab samples. Twenty-nine of these samples were found to be positive for BRV using RT-LAMP. The BRV-specific-RT-LAMP results were also confirmed by real-time RT-PCR assay. Conclusions The bovine rotavirus-specific RT-LAMP assay was highly sensitive and holds promise as a prompt and simple diagnostic method for the detection of group A bovine rotavirus infection in young calves.
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Affiliation(s)
- Zhixun Xie
- Department of Biotechnology, Guangxi Veterinary Research Institute, 51 You Ai Road, Nanning, Guangxi, 530001, China.
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Abstract
A “Meeting on Upstream Rotavirus Vaccines and Emerging Vaccine Producers” was held at the World Health Organization in Geneva, Switzerland on March 28–30, 2006. The purpose was to discuss, evaluate, and weigh the importance of additional rotavirus vaccine candidates following the successful international licensure of rotavirus vaccines by two major pharmaceutical companies (GlaxoSmithKline and Merck) that had been in development for many years. Both licensed vaccines are composed of live rotaviruses that are delivered orally as have been all candidate rotavirus vaccines evaluated in humans. Each is built on the experience gained with previous candidates whose development had either been discontinued or, in the case of the previously licensed rhesus rotavirus reassortant vaccine (Rotashield), was withdrawn by its manufacturer after the discovery of a rare association with intussusception. Although which alternative candidate vaccines should be supported for development and where this should be done are controversial topics, there was general agreement expressed at the Geneva meeting that further development of alternative candidates is a high priority. This development will help insure that the most safe, effective and economic vaccines are available to children in Third World nations where the vast majority of the >600,000 deaths due to rotavirus occur each year. This review is intended to provide the history and present status of rotavirus vaccines as well as a perspective on the future development of candidate vaccines as a means of promulgating plans suggested at the Geneva meeting.
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Affiliation(s)
- Richard L Ward
- Division of Infectious Diseases, Cincinnati Children's Hospital Medical Center Cincinnati, OH, USA
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8
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Corthésy B, Benureau Y, Perrier C, Fourgeux C, Parez N, Greenberg H, Schwartz-Cornil I. Rotavirus anti-VP6 secretory immunoglobulin A contributes to protection via intracellular neutralization but not via immune exclusion. J Virol 2006; 80:10692-9. [PMID: 16956954 PMCID: PMC1641769 DOI: 10.1128/jvi.00927-06] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Immunoglobulin A (IgA) monoclonal antibodies (MAbs) directed at the conserved inner core protein VP6 of rotavirus, such as the IgA7D9 MAb, provide protective immunity in adult and suckling mice when delivered systemically. While these antibodies do not have traditional in vitro neutralizing activity, they could mediate their antiviral activity either by interfering with the viral replication cycle along the IgA secretory pathway or by acting at mucosal surfaces as secretory IgA and excluding virus from target enterocytes. We sought to determine the critical step at which antirotaviral activity was initiated by the IgA7D9 MAb. The IgA7D9 MAb appeared to directly interact with purified triple-layer viral particles, as shown by immunoprecipitation and immunoblotting. However, protection was not conferred by passively feeding mice with the secretory IgA7D9 MAb. This indicates that the secretory IgA7D9 MAb does not confer protection by supplying immune exclusion activity in vivo. We next evaluated the capacity of polymeric IgA7D9 MAb to neutralize rotavirus intracellularly during transcytosis. We found that when polymeric IgA7D9 MAb was applied to the basolateral pole of polarized Caco-2 intestinal cells, it significantly reduced viral replication and prevented the loss of barrier function induced by apical exposure of the cell monolayer to rotavirus, supporting the conclusion that the antibody carries out its antiviral activity intracellularly. These findings identify a mechanism whereby the well-conserved immunodominant VP6 protein can function as a target for heterotypic antibodies and protective immunity.
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Affiliation(s)
- Blaise Corthésy
- R & D Laboratory of the Division of Immunology and Allergy, DMI-CHUV, Rue du Bugnon, 1011 Lausanne, Switzerland
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9
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Yoder JD, Dormitzer PR. Alternative intermolecular contacts underlie the rotavirus VP5* two- to three-fold rearrangement. EMBO J 2006; 25:1559-68. [PMID: 16511559 PMCID: PMC1440311 DOI: 10.1038/sj.emboj.7601034] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2005] [Accepted: 02/14/2006] [Indexed: 11/08/2022] Open
Abstract
The spike protein VP4 is a key component of the membrane penetration apparatus of rotavirus, a nonenveloped virus that causes childhood gastroenteritis. Trypsin cleavage of VP4 produces a fragment, VP5*, with a potential membrane interaction region, and primes rotavirus for cell entry. During entry, the part of VP5* that protrudes from the virus folds back on itself and reorganizes from a local dimer to a trimer. Here, we report that a globular domain of VP5*, the VP5* antigen domain, is an autonomously folding unit that alternatively forms well-ordered dimers and trimers. Because the domain contains heterotypic neutralizing epitopes and is soluble when expressed directly, it is a promising potential subunit vaccine component. X-ray crystal structures show that the dimer resembles the spike body on trypsin-primed virions, and the trimer resembles the folded-back form of the spike. The same structural elements pack differently to form key intermolecular contacts in both oligomers. The intrinsic molecular property of alternatively forming dimers and trimers facilitates the VP5* reorganization, which is thought to mediate membrane penetration during cell entry.
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Affiliation(s)
- Joshua D Yoder
- Program in Virology, Laboratory of Molecular Medicine, Harvard Medical School, Children's Hospital, Boston, MA, USA
| | - Philip R Dormitzer
- Program in Virology, Laboratory of Molecular Medicine, Harvard Medical School, Children's Hospital, Boston, MA, USA
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10
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Kraschnefski MJ, Scott SA, Holloway G, Coulson BS, von Itzstein M, Blanchard H. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of the VP8* carbohydrate-binding protein of the human rotavirus strain Wa. Acta Crystallogr Sect F Struct Biol Cryst Commun 2005; 61:989-93. [PMID: 16511215 PMCID: PMC1978132 DOI: 10.1107/s1744309105032999] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Accepted: 10/14/2005] [Indexed: 01/09/2023]
Abstract
Rotaviruses exhibit host-specificity and the first crystallographic information on a rotavirus strain that infects humans is reported here. Recognition and attachment to host cells, leading to invasion and infection, is critically linked to the function of the outer capsid spike protein of the rotavirus particle. In some strains the VP8* component of the spike protein is implicated in recognition and binding of sialic-acid-containing cell-surface carbohydrates, thereby enabling infection by the virus. The cloning, expression, purification, crystallization and initial X-ray diffraction analysis of the VP8* core from human Wa rotavirus is reported. Two crystal forms (trigonal P3(2)21 and monoclinic P2(1)) have been obtained and X-ray diffraction data have been collected, enabling determination of the VP8*(64-223) structure by molecular replacement.
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Affiliation(s)
- Mark J. Kraschnefski
- Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 50 Gold Coast Mail Centre, Queensland 9726, Australia
| | - Stacy A. Scott
- Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 50 Gold Coast Mail Centre, Queensland 9726, Australia
| | - Gavan Holloway
- Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010, Australia
| | - Barbara S. Coulson
- Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010, Australia
| | - Mark von Itzstein
- Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010, Australia
| | - Helen Blanchard
- Institute for Glycomics, Griffith University (Gold Coast Campus), PMB 50 Gold Coast Mail Centre, Queensland 9726, Australia
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11
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Scott SA, Holloway G, Coulson BS, Szyczew AJ, Kiefel MJ, von Itzstein M, Blanchard H. Crystallization and preliminary X-ray diffraction analysis of the sialic acid-binding domain (VP8*) of porcine rotavirus strain CRW-8. Acta Crystallogr Sect F Struct Biol Cryst Commun 2005; 61:617-20. [PMID: 16511112 PMCID: PMC1952324 DOI: 10.1107/s1744309105013849] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2005] [Accepted: 05/03/2005] [Indexed: 11/10/2022]
Abstract
Rotavirus recognition and attachment to host cells involves interaction with the spike protein VP4 that projects outwards from the surface of the virus particle. An integral component of these spikes is the VP8* domain, which is implicated in the direct recognition and binding of sialic acid-containing cell-surface carbohydrates and facilitates subsequent invasion by the virus. The expression, purification, crystallization and preliminary X-ray diffraction analysis of VP8* from porcine CRW-8 rotavirus is reported. Diffraction data have been collected to 2.3 A resolution, enabling the determination of the VP8* structure by molecular replacement.
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Affiliation(s)
- Stacy A. Scott
- Institute for Glycomics, Griffith University (Gold Coast Campus) PMB 50, Gold Coast Mail Centre, Queensland 9726, Australia
| | - Gavan Holloway
- Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010, Australia
| | - Barbara S. Coulson
- Department of Microbiology and Immunology, The University of Melbourne, Victoria 3010, Australia
| | - Alex J. Szyczew
- Institute for Glycomics, Griffith University (Gold Coast Campus) PMB 50, Gold Coast Mail Centre, Queensland 9726, Australia
| | - Milton J. Kiefel
- Institute for Glycomics, Griffith University (Gold Coast Campus) PMB 50, Gold Coast Mail Centre, Queensland 9726, Australia
| | - Mark von Itzstein
- Institute for Glycomics, Griffith University (Gold Coast Campus) PMB 50, Gold Coast Mail Centre, Queensland 9726, Australia
| | - Helen Blanchard
- Institute for Glycomics, Griffith University (Gold Coast Campus) PMB 50, Gold Coast Mail Centre, Queensland 9726, Australia
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12
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Golantsova NE, Gorbunova EE, Mackow ER. Discrete domains within the rotavirus VP5* direct peripheral membrane association and membrane permeability. J Virol 2004; 78:2037-44. [PMID: 14747568 PMCID: PMC369428 DOI: 10.1128/jvi.78.4.2037-2044.2004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cleavage of the rotavirus spike protein, VP4, is required for rotavirus-induced membrane permeability and viral entry into cells. The VP5* cleavage product selectively permeabilizes membranes and liposomes and contains an internal hydrophobic domain that is required for membrane permeability. Here we investigate VP5* domains (residues 248 to 474) that direct membrane binding. We determined that expressed VP5 fragments containing residues 248 to 474 or 265 to 474, including the internal hydrophobic domain, bind to cellular membranes but are not present in Triton X-100-resistant membrane rafts. Expressed VP5 partitions into aqueous but not detergent phases of Triton X-114, suggesting that VP5 is not integrally inserted into membranes. Since high-salt or alkaline conditions eluted VP5 from membranes, our findings demonstrate that VP5 is peripherally associated with membranes. Interestingly, mutagenesis of residue 394 (W-->R) within the VP5 hydrophobic domain, which abolishes VP5-directed permeability, had no effect on VP5's peripheral membrane association. In contrast, deletion of N-terminal VP5 residues (residues 265 to 279) abolished VP5 binding to membranes. Alanine mutagenesis of two positively charged residues within this domain (residues 274R and 276K) dramatically reduced (>95%) binding of VP5 to membranes and suggested their potential interaction with polar head groups of the lipid bilayer. Mutations in either the VP5 hydrophobic or basic domain blocked VP5-directed permeability of cells. These findings indicate that there are at least two discrete domains within VP5* required for pore formation: an N-terminal basic domain that permits VP5* to peripherally associate with membranes and an internal hydrophobic domain that is essential for altering membrane permeability. These results provide a fundamental understanding of interactions between VP5* and the membrane, which are required for rotavirus entry.
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Affiliation(s)
- Nina E Golantsova
- Department of Medicine, Stony Brook University, Stony Brook, New York 11794, USA
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Berois M, Sapin C, Erk I, Poncet D, Cohen J. Rotavirus nonstructural protein NSP5 interacts with major core protein VP2. J Virol 2003; 77:1757-63. [PMID: 12525609 PMCID: PMC140918 DOI: 10.1128/jvi.77.3.1757-1763.2003] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rotavirus is a nonenveloped virus with a three-layered capsid. The inner layer, made of VP2, encloses the genomic RNA and two minor proteins, VP1 and VP3, with which it forms the viral core. Core assembly is coupled with RNA viral replication and takes place in definite cellular structures termed viroplasms. Replication and encapsidation mechanisms are still not fully understood, and little information is available about the intermolecular interactions that may exist among the viroplasmic proteins. NSP2 and NSP5 are two nonstructural viroplasmic proteins that have been shown to interact with each other. They have also been found to be associated with precore replication intermediates that are precursors of the viral core. In this study, we show that NSP5 interacts with VP2 in infected cells. This interaction was demonstrated with recombinant proteins expressed from baculovirus recombinants or in bacterial systems. NSP5-VP2 interaction also affects the stability of VP6 bound to VP2 assemblies. The data presented showed evidence, for the first time, of an interaction between VP2 and a nonstructural rotavirus protein. Published data and the interaction demonstrated here suggest a possible role for NSP5 as an adapter between NSP2 and the replication complex VP2-VP1-VP3 in core assembly and RNA encapsidation, modulating the role of NSP2 as a molecular motor involved in the packaging of viral mRNA.
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Affiliation(s)
- Mabel Berois
- Seccion Virologia, Facultad de Ciencias, Montevideo 11400, Uruguay.
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14
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Thouvenin E, Schoehn G, Rey F, Petitpas I, Mathieu M, Vaney MC, Cohen J, Kohli E, Pothier P, Hewat E. Antibody inhibition of the transcriptase activity of the rotavirus DLP: a structural view. J Mol Biol 2001; 307:161-72. [PMID: 11243811 DOI: 10.1006/jmbi.2000.4479] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
On entering the host cell the rotavirus virion loses its outer shell to become a double-layered particle (DLP). The DLP then transcribes the 11 segments of its dsRNA genome using its own transcriptase complex, and the mature mRNA emerges along the 5-fold axis. In order to better understand the transcription mechanism and the role of VP6 in transcription we have studied three monoclonal antibodies against VP6: RV-238 which inhibits the transcriptase activity of the DLP; and RV-133 and RV-138 which have no effect on transcription. The structures obtained by cryo-electron microscopy of the DLP/Fab complexes and by X-ray crystallography of the VP6 trimer and the VP6/Fab-238 complex have been combined to give pseudo-atomic structures. Steric hindrance between the Fabs results in limited Fab occupancy. In particular, there are on average only three of a possible five Fabs-238 which point towards the 5-fold axis. Thus, Fabs-238 are not in a position to block the exiting mRNA, nor is there any visible conformational change in VP6 on antibody binding at a resolution of 23 A. However, the epitope of the inhibiting antibody involves two VP6 monomers, whereas, those of the non-inhibiting antibodies have an epitope on only one VP6. Thus, the inhibition of transcription may be a result of inhibition of a possible change in the VP6 conformation associated with the transcription of mRNA.
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Affiliation(s)
- E Thouvenin
- Institut de Biologie Structurale, 41 rue Jules Horowitz, 38027 Grenoble, France
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15
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Dowling W, Denisova E, LaMonica R, Mackow ER. Selective membrane permeabilization by the rotavirus VP5* protein is abrogated by mutations in an internal hydrophobic domain. J Virol 2000; 74:6368-76. [PMID: 10864647 PMCID: PMC112143 DOI: 10.1128/jvi.74.14.6368-6376.2000] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Rotavirus infectivity is dependent on the proteolytic cleavage of the VP4 spike protein into VP8* and VP5* proteins. Proteolytically activated virus, as well as expressed VP5*, permeabilizes membranes, suggesting that cleavage exposes a membrane-interactive domain of VP5* which effects rapid viral entry. The VP5* protein contains a single long hydrophobic domain (VP5*-HD, residues 385 to 404) at an internal site. In order to address the role of the VP5*-HD in permeabilizing cellular membranes, we analyzed the entry of o-nitrophenyl-beta-D-galactopyranoside (ONPG) into cells induced to express VP5* or mutated VP5* polypeptides. Following IPTG (isopropyl-beta-D-thiogalactopyranoside) induction, VP5* and VP5* truncations containing the VP5*-HD permeabilized cells to the entry and cleavage of ONPG, while VP8* and control proteins had no effect on cellular permeability. Expression of VP5* deletions containing residues 265 to 474 or 265 to 404 permeabilized cells; however, C-terminal truncations which remove the conserved GGA (residues 399 to 401) within the HD abolished membrane permeability. Site-directed mutagenesis of the VP5-HD further demonstrated a requirement for residues within the HD for VP5*-induced membrane permeability. Functional analysis of mutant VP5*s indicate that conserved glycines within the HD are required and suggest that a random coiled structure rather than the strictly hydrophobic character of the domain is required for permeability. Expressed VP5* did not alter bacterial growth kinetics or lyse bacteria following induction. Instead, VP5*-mediated size-selective membrane permeability, releasing 376-Da carboxyfluorescein but not 4-kDa fluorescein isothiocyanate-dextran from preloaded liposomes. These findings suggest that the fundamental role for VP5* in the rotavirus entry process may be to expose triple-layered particles to low [Ca](i), which uncoats the virus, rather than to effect the detergent-like lysis of early endosomal membranes.
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Affiliation(s)
- W Dowling
- Department of Medicine, SUNY at Stony Brook, Stony Brook, New York 11794-8173, USA
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16
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Omura T, Yan J. Role of outer capsid proteins in transmission of Phytoreovirus by insect vectors. Adv Virus Res 1999; 54:15-43. [PMID: 10547673 DOI: 10.1016/s0065-3527(08)60364-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- T Omura
- National Agriculture Research Center, Tsukuba, Ibaraki, Japan
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17
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Petitpas I. Étude structurale de la protéine VP6 des rotavirus et de l'inhibition de la transcription virale par des anticorps monoclonaux dirigés contre VP6. Med Mal Infect 1999. [DOI: 10.1016/s0399-077x(00)80086-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Affiliation(s)
- T Belhorn
- Division of Infectious Diseases, University of Texas Health Sciences Center, Houston, USA
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19
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Denisova E, Dowling W, LaMonica R, Shaw R, Scarlata S, Ruggeri F, Mackow ER. Rotavirus capsid protein VP5* permeabilizes membranes. J Virol 1999; 73:3147-53. [PMID: 10074166 PMCID: PMC104076 DOI: 10.1128/jvi.73.4.3147-3153.1999] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Proteolytic cleavage of the VP4 outer capsid spike protein into VP8* and VP5* proteins is required for rotavirus infectivity and for rotavirus-induced membrane permeability. In this study we addressed the function of the VP5* cleavage fragment in permeabilizing membranes. Expressed VP5* and truncated VP5* proteins were purified by nickel affinity chromatography and assayed for their ability to permeabilize large unilamellar vesicles (LUVs) preloaded with carboxyfluorescein (CF). VP5* and VP5* truncations, but not VP4 or VP8*, permeabilized LUVs as measured by fluorescence dequenching of released CF. Similar to virus-induced CF release, VP5*-induced CF release was concentration and temperature dependent, with a pH optimum of 7.35 at 37 degrees C, but independent of the presence of divalent cations or cholesterol. VP5*-induced permeability was completely inhibited by VP5*-specific neutralizing monoclonal antibodies (2G4, M2, or M7) which recognize conformational epitopes on VP5* but was not inhibited by VP8*-specific neutralizing antibodies. In addition, N-terminal and C-terminal VP5* truncations including residues 265 to 474 are capable of permeabilizing LUVs. These findings demonstrate that VP5* permeabilizes membranes in the absence of other rotavirus proteins and that membrane-permeabilizing VP5* truncations contain the putative fusion region within predicted virion surface domains. The ability of recombinant expressed VP5* to permeabilize membranes should permit us to functionally define requirements for VP5*-membrane interactions. These findings indicate that VP5* is a specific membrane-permeabilizing capsid protein which is likely to play a role in the cellular entry of rotaviruses.
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Affiliation(s)
- E Denisova
- Department of Medicine, SUNY at Stony Brook, Stony Brook, New York, USA
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20
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Jiang B, Barniak V, Smith RP, Sharma R, Corsaro B, Hu B, Madore HP. Synthesis of rotavirus-like particles in insect cells: comparative and quantitative analysis. Biotechnol Bioeng 1998; 60:369-74. [PMID: 10099441 DOI: 10.1002/(sici)1097-0290(19981105)60:3<369::aid-bit14>3.0.co;2-h] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
When the three major structural proteins, VP2, VP6, and VP7, of rotavirus are co-expressed in insect cells infected with recombinant baculoviruses, they self-assemble into triple-layered virus-like particles (VLPs) that are similar in morphology to native rotavirus. In order to establish the most favorable conditions for the synthesis of rotavirus VLPs, we have compared the kinetics of 2/6/7-VLP synthesis in two different insect cell lines: High Five cells propagated in Excell 405 medium and Spodoptera frugiperda 9 cells in Excell 400 medium. The majority of VLPs produced in both cell lines were released into the culture medium, and these released VLPs were predominantly triple-layered and were found to be stable for the period of six or seven days examined. The optimal synthesis of VLPs depended upon the cell line and the culture medium used as well as the time of harvesting infected cell cultures. The highest yield of VLPs was obtained from High Five cultures in the late phase of infection when the yield was at least 5-fold higher than that from S. frugiperda 9 cultures on a per cell basis. Our results demonstrate the usefulness of High Five cells for the production of VLPs as potential rotavirus subunit vaccines.
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Affiliation(s)
- B Jiang
- Wyeth-Lederle Vaccines and Pediatrics, 401 North Middletown Road, Pearl River, New York 10965, USA
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21
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Zeng CQ, Estes MK, Charpilienne A, Cohen J. The N terminus of rotavirus VP2 is necessary for encapsidation of VP1 and VP3. J Virol 1998; 72:201-8. [PMID: 9420216 PMCID: PMC109365 DOI: 10.1128/jvi.72.1.201-208.1998] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/1997] [Accepted: 09/23/1997] [Indexed: 02/05/2023] Open
Abstract
The innermost core of rotavirus is composed of VP2, which forms a protein layer that surrounds the two minor proteins VP1 and VP3, and the genome of 11 segments of double-stranded RNA. This inner core layer surrounded by VP6, the major capsid protein, constitutes double-layered particles that are transcriptionally active. Each gene encoding a structural protein of double-layered particles has been cloned into baculovirus recombinants and expressed in insect cells. Previously, we showed that coexpression of different combinations of the structural proteins of rotavirus double-layered particles results in the formation of virus-like particles (VLPs), and each VLP containing VP1, the presumed RNA-dependent RNA polymerase, possesses replicase activity as assayed in an in vitro template-dependent assay system (C. Q.-Y. Zeng, M. J. Wentz, J. Cohen, M. E. Estes, and R. F. Ramig, J. Virol. 70:2736-2742, 1996). This work reports construction and characterization of VLPs containing a truncated VP2 (VPdelta2, containing amino acids [aa] Met-93 to 880). Expression of VPdelta2 alone resulted in the formation of single-layered delta2-VLPs. Coexpression of VPdelta2 with VP6 produced double-layered delta2/6-VLPs. VLPs formed by coexpression of VPdelta2 and VP1 or VP3, or both VP1 and VP3, resulted in the formation of VLPs lacking both VP1 and VP3. The presence of VP6 with VPdelta2 did not result in encapsidation of VP1 and VP3. To determine the domain of VP2 required for binding VP1, far-Western blot analyses using a series of truncated VP2 constructs were performed to test their ability to bind VP1. These analyses showed that (i) full-length VP2 (aa 1 to 880) binds to VP1, (ii) any N-terminal truncation lacking aa 1 to 25 fails to bind VP1, and (iii) a C-terminal 296-aa truncated VP2 construct (aa 1 to 583) maintains the ability to bind VP1. These analyses indicate that the N terminus of rotavirus VP2 is necessary for the encapsidation of VP1 and VP3.
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Affiliation(s)
- C Q Zeng
- Division of Molecular Virology, Baylor College of Medicine, Houston, Texas 77030, USA.
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22
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Desselberger U. Viral factors determining rotavirus pathogenicity. ARCHIVES OF VIROLOGY. SUPPLEMENTUM 1997; 13:131-9. [PMID: 9413533 DOI: 10.1007/978-3-7091-6534-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The pathogenicity of rotaviruses depends on multiple viral and host factors. Evidence is presented for the involvement of a number of viral genes (coding for structural and non-structural proteins) in the ability of the virus to cause diarrhoea. Different genes are important in different rotavirus--host systems suggesting that there is no single viral pathogenicity factor.
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Affiliation(s)
- U Desselberger
- Clinical Microbiology and Public Health Laboratory, Addenbrooke's Hospital, Cambridge, U.K
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23
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Prasad BV, Rothnagel R, Zeng CQ, Jakana J, Lawton JA, Chiu W, Estes MK. Visualization of ordered genomic RNA and localization of transcriptional complexes in rotavirus. Nature 1996; 382:471-3. [PMID: 8684490 DOI: 10.1038/382471a0] [Citation(s) in RCA: 176] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In double-stranded-RNA (dsRNA) viruses found in animals, bacteria and yeast, the genome is transcribed within the structurally intact core of the virion with extraordinary efficiency. The structural organization of the genome and the enzymes involved in the transcription inside any of these viruses, critical for understanding this process, is not known. Here we report what we believe is the first three-dimensional characterization of the viral genome and the transcription complex in a prototypical dsRNA virus. Rotavirus is a large (diameter 1,000 A) icosahedral virus composed of three capsid protein layers and 11 dsRNA segments. It is the most important cause of gastroenteritis in children, accounting for over a million deaths annually. We show that viral dsRNA forms a dodecahedral structure in which the RNA double helices, interacting closely with the inner capsid layer, are packed around the enzyme complex located at the icosahedral 5-fold axes. The ordered RNA accounts for about 4,500 out of a total 18,525 base pairs in the genome, the largest amount of icosahedrally ordered RNA observed in any virus structure to date. We propose that the observed organization of the dsRNA is conducive for an orchestrated movement of the RNA relative to the enzyme complex during transcription.
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Affiliation(s)
- B V Prasad
- Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, Texas 77030, USA
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24
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Zeng CQ, Wentz MJ, Cohen J, Estes MK, Ramig RF. Characterization and replicase activity of double-layered and single-layered rotavirus-like particles expressed from baculovirus recombinants. J Virol 1996; 70:2736-42. [PMID: 8627747 PMCID: PMC190130 DOI: 10.1128/jvi.70.5.2736-2742.1996] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Rotavirus has a capsid composed of three concentric protein layers. We coexpressed various combinations of the rotavirus structural proteins of single-layered (core) and double-layered (single-shelled) capsids from baculovirus vectors in insect cells and determined the ability of the various combinations to assemble into viruslike particles (VLPs). VLPs were purified by centrifugation, their structure was examined by negative-stain electron microscopy, their protein content was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and GTP binding assays, and their ability to support synthesis of negative-strand RNAs on positive-sense template RNAs was determined in an in vitro replication system. Coexpression of all possible combinations of VP1, VP2, VP3, and VP6, the proteins of double-layered capsids, resulted in the formation of VP1/2/3/6, VP1/2/6, VP2/3/6, and VP2/6 double-layered VLPs. These VLPs had the structural characteristics of empty rotavirus double-layered particles and contained the indicated protein species. Only VPI/2/3/6 and VP1/2/6 particles supported RNA replication. Coexpression of all possible combinations of VPl, VP2, and VP3, the proteins of single-layered capsids, resulted in the formation of VP1/2/3, VP1/2, VP2/3, and VP2 single-layered VLPs. These VLPs had the structural characteristics of empty single-layered rotavirus particles and contained the indicated protein species. Only VP1/2/3 and VP1/2 VLPs supported RNA replication. We conclude that (i) the assembly of VP1 and VP3 into VLPs requires the presence of VP2, (ii) the role of VP2 in the assembly of VP1 and VP3 and in replicase activity is most likely structural, (iii) VP1 is required and VP3 is not required for replicase activity of VLPs, and (iv) VP1/2 VLPs constitute the minimal replicase particle in the in vitro replication system.
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Affiliation(s)
- C Q Zeng
- Division of Molecular Virology, Baylor College of Medicine, Houston, Texas 77030, USA
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25
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Ward RL, Jin Q, Nakagomi O, Sander DS, Gentsch JR. Isolation of a human rotavirus containing a bovine rotavirus VP4 gene that suppresses replication of other rotaviruses in coinfected cells. Arch Virol 1996; 141:615-33. [PMID: 8645099 DOI: 10.1007/bf01718321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Bovine-human reassortant strains containing ten human rotavirus gene segments and segment 4, encoding VP4, of a bovine rotavirus were isolated from the stool of an infected Bangladeshi infant during cell culture adaptation. Two plaque purified variants of this reassortant, one making very large (429-L4) and the other tiny (429-S4) plaques, were further analyzed. The electropherotypes of these variants were identical except for slight mobility differences in segment 4. The predicted sequence of amino acids (aa) 16-280 in VP4 proteins revealed four differences between variants even in this limited region, so no single difference could be linked to plaque size. The small plaque variant S4 was phenotypically unstable and mutated to a large plaque-former within a single cell culture passage. The predicted sequence of aa 16-280 of a large plaque variant derived from S4 revealed six changes, only one of which was common to that of the L4 strain, thus suggesting that multiple amino acid changes in VP4 may affect plaque size. Although the large plaque variant L4 grew faster and was released from cells more rapidly than S4, its replication and that of other rotaviruses tested (i.e. RRV, NCDV and Wa) was suppressed by S4 in coinfected cells. Using an RRV x S4 reassortant containing only RRV segment 4, it was established that suppression was linked to the S4 VP4 protein. This suppression could not be associated with inhibition of viral adsorption and, therefore, appeared to occur following internalization. Thus, a new property of the rotavirus VP4 protein has been identified in a bovine-human rotavirus reas-sortant.
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Affiliation(s)
- R L Ward
- Division of Clinical Virology, James N. Gamble Institute of Medical Research, Cincinnati, Ohio, USA
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26
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Samarbaf-Zadeh AR, Lambden PR, Green SM, Deng Y, Caul EO, Clarke IN. The VP3 gene of human group C rotavirus. Virus Genes 1996; 13:169-73. [PMID: 8972570 DOI: 10.1007/bf00568909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The complete nucleotide sequence of genome segment 4 from the human group C rotavirus (Bristol strain) was determined. Comparison of the nucleotide sequences of the genome termini with the consensus 5' and 3' terminal non-coding sequences of the human group C rotavirus genome revealed characteristic 5' and 3' sequence motifs. Human group C rotavirus genome segment 4 is 2,166bp long and encodes a single open reading frame of 2,082 nucleotides (693 amino acids) starting at nucleotide 55 and terminating at nucleotide 2,136 giving a 3' untranslated region of 30 nucleotides. Alignment with the porcine group C VP3 equivalent gene showed the human gene is one amino acid longer, and that the proteins have 84.1% amino acid sequence identity. A conserved potential nucleotide binding motif shared with the porcine VP3 sequence was identified. Analogy with the group A rotaviruses suggested that the genome segment 4 encodes the group C rotavirus guanylyltransferase.
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27
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Shaw AL, Rothnagel R, Zeng CQ, Lawton JA, Ramig RF, Estes MK, Prasad BV. Rotavirus structure: interactions between the structural proteins. ARCHIVES OF VIROLOGY. SUPPLEMENTUM 1996; 12:21-7. [PMID: 9015098 DOI: 10.1007/978-3-7091-6553-9_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Structural studies on rotavirus using electron cryomicroscopy and computer image analysis have permitted visualization of each shell in the triple-layered rotavirus structure. Biochemical results have aided our interpretation of the structural organization of these layers and protein interactions seen in the three-dimensional structure, and have provided a better understanding of the structure-function relationships of the rotavirus structural proteins.
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Affiliation(s)
- A L Shaw
- Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, Texas, USA
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