1
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Eruera AR, McSweeney AM, McKenzie-Goldsmith GM, Opel-Reading HK, Thomas SX, Campbell AC, Stubbing L, Siow A, Hubert JG, Brimble MA, Ward VK, Krause KL. Crystal Structure of Inhibitor-Bound GII.4 Sydney 2012 Norovirus 3C-Like Protease. Viruses 2023; 15:2202. [PMID: 38005879 PMCID: PMC10674469 DOI: 10.3390/v15112202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/26/2023] [Accepted: 10/30/2023] [Indexed: 11/26/2023] Open
Abstract
Norovirus is the leading cause of viral gastroenteritis worldwide, and there are no approved vaccines or therapeutic treatments for chronic or severe norovirus infections. The structural characterisation of the norovirus protease and drug development has predominantly focused upon GI.1 noroviruses, despite most global outbreaks being caused by GII.4 noroviruses. Here, we determined the crystal structures of the GII.4 Sydney 2012 ligand-free norovirus protease at 2.79 Å and at 1.83 Å with a covalently bound high-affinity (IC50 = 0.37 µM) protease inhibitor (NV-004). We show that the active sites of the ligand-free protease structure are present in both open and closed conformations, as determined by their Arg112 side chain orientation. A comparative analysis of the ligand-free and ligand-bound protease structures reveals significant structural differences in the active site cleft and substrate-binding pockets when an inhibitor is covalently bound. We also report a second molecule of NV-004 non-covalently bound within the S4 substrate binding pocket via hydrophobic contacts and a water-mediated hydrogen bond. These new insights can guide structure-aided drug design against the GII.4 genogroup of noroviruses.
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Affiliation(s)
- Alice-Roza Eruera
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.); (S.X.T.)
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (H.K.O.-R.); (A.C.C.)
| | - Alice M. McSweeney
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.); (S.X.T.)
| | - Geena M. McKenzie-Goldsmith
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.); (S.X.T.)
| | - Helen K. Opel-Reading
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (H.K.O.-R.); (A.C.C.)
| | - Simone X. Thomas
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.); (S.X.T.)
| | - Ashley C. Campbell
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (H.K.O.-R.); (A.C.C.)
| | - Louise Stubbing
- School of Chemical Sciences, The University of Auckland, 23 Symonds Street and 3b Symonds Street, Auckland 1142, New Zealand; (L.S.); (A.S.); (J.G.H.); (M.A.B.)
| | - Andrew Siow
- School of Chemical Sciences, The University of Auckland, 23 Symonds Street and 3b Symonds Street, Auckland 1142, New Zealand; (L.S.); (A.S.); (J.G.H.); (M.A.B.)
| | - Jonathan G. Hubert
- School of Chemical Sciences, The University of Auckland, 23 Symonds Street and 3b Symonds Street, Auckland 1142, New Zealand; (L.S.); (A.S.); (J.G.H.); (M.A.B.)
| | - Margaret A. Brimble
- School of Chemical Sciences, The University of Auckland, 23 Symonds Street and 3b Symonds Street, Auckland 1142, New Zealand; (L.S.); (A.S.); (J.G.H.); (M.A.B.)
| | - Vernon K. Ward
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.); (S.X.T.)
| | - Kurt L. Krause
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand; (H.K.O.-R.); (A.C.C.)
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2
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Stubbing LA, Hubert JG, Bell-Tyrer J, Hermant YO, Yang SH, McSweeney AM, McKenzie-Goldsmith GM, Ward VK, Furkert DP, Brimble MA. P 1 Glutamine isosteres in the design of inhibitors of 3C/3CL protease of human viruses of the Pisoniviricetes class. RSC Chem Biol 2023; 4:533-547. [PMID: 37547456 PMCID: PMC10398354 DOI: 10.1039/d3cb00075c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 06/19/2023] [Indexed: 08/08/2023] Open
Abstract
Viral infections are one of the leading causes of acute morbidity in humans and much endeavour has been made by the synthetic community for the development of drugs to treat associated diseases. Peptide-based enzyme inhibitors, usually short sequences of three or four residues, are one of the classes of compounds currently under development for enhancement of their activity and pharmaceutical properties. This review reports the advances made in the design of inhibitors targeting the family of highly conserved viral proteases 3C/3CLpro, which play a key role in viral replication and present minimal homology with mammalian proteases. Particular focus is put on the reported development of P1 glutamine isosteres to generate potent inhibitors mimicking the natural substrate sequence at the site of recognition.'
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Affiliation(s)
- Louise A Stubbing
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
| | - Jonathan G Hubert
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
| | - Joseph Bell-Tyrer
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
| | - Yann O Hermant
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
| | - Sung Hyun Yang
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
| | - Alice M McSweeney
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago PO Box 56, 720 Cumberland Street Dunedin 9054 New Zealand
| | - Geena M McKenzie-Goldsmith
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago PO Box 56, 720 Cumberland Street Dunedin 9054 New Zealand
| | - Vernon K Ward
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago PO Box 56, 720 Cumberland Street Dunedin 9054 New Zealand
| | - Daniel P Furkert
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
| | - Margaret A Brimble
- School of Chemical Sciences, The University of Auckland 23 Symonds Street and 3b Symonds Street Auckland 1142 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland 3b Symonds Street Auckland 1142 New Zealand
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3
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Wobus CE, Peiper AM, McSweeney AM, Young VL, Chaika M, Lane MS, Lingemann M, Deerain JM, Strine MS, Alfajaro MM, Helm EW, Karst SM, Mackenzie JM, Taube S, Ward VK, Wilen CB. Murine Norovirus: Additional Protocols for Basic and Antiviral Studies. Curr Protoc 2023; 3:e828. [PMID: 37478303 PMCID: PMC10375541 DOI: 10.1002/cpz1.828] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
Murine norovirus (MNV) is a positive-sense, plus-stranded RNA virus in the Caliciviridae family. Viruses in this family replicate in the intestine and are transmitted by the fecal-oral route. MNV is related to the human noroviruses, which cause the majority of nonbacterial gastroenteritis worldwide. Given the technical challenges in studying human norovirus, MNV is often used to study mechanisms in norovirus biology since it combines the availability of a cell culture and reverse genetics system with the ability to study infection in the native host. Adding to our previous protocol collection, here we describe additional techniques that have since been developed to study MNV biology. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Indirect method for measuring cell cytotoxicity and antiviral activity Basic Protocol 2: Measuring murine norovirus genome titers by RT-qPCR Support Protocol 1: Preparation of standard Basic Protocol 3: Generation of recombinant murine norovirus with minimal passaging Basic Protocol 4: Generation of recombinant murine norovirus via circular polymerase extension reaction (CPER) Basic Protocol 5: Expression of norovirus NS1-2 in insect cell suspension cultures using a recombinant baculovirus Support Protocol 2: Isotope labelling of norovirus NS1-2 in insect cells Support Protocol 3: Purification of the norovirus NS1-2 protein Support Protocol 4: Expression of norovirus NS1-2 in mammalian cells by transduction with a recombinant baculovirus Basic Protocol 6: Infection of enteroids in transwell inserts with murine norovirus Support Protocol 5: Preparation of conditioned medium for enteroids culture Support Protocol 6: Isolation of crypts for enteroids generation Support Protocol 7: Enteroid culture passaging and maintenance Basic Protocol 7: Quantification of murine norovirus-induced diarrhea using neonatal mouse infections Alternate Protocol 1: Intragastric inoculation of neonatal mice Alternate Protocol 2: Scoring colon contents.
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Affiliation(s)
- Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan
| | - Amy M Peiper
- Department of Molecular Genetics & Microbiology, University of Florida, Gainesville, Florida
| | - Alice M McSweeney
- Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand
| | - Vivienne L Young
- Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand
| | - Maryna Chaika
- Institute of Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Miranda Sophie Lane
- Institute of Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Marit Lingemann
- Institute of Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Joshua M Deerain
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Madison S Strine
- Departments of Immunobiology and Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Mia Madel Alfajaro
- Departments of Immunobiology and Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Emily W Helm
- Department of Molecular Genetics & Microbiology, University of Florida, Gainesville, Florida
| | - Stephanie M Karst
- Department of Molecular Genetics & Microbiology, University of Florida, Gainesville, Florida
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, University of Melbourne, Melbourne, Australia
| | - Stefan Taube
- Institute of Virology and Cell Biology, University of Lübeck, Lübeck, Germany
| | - Vernon K Ward
- Department of Microbiology & Immunology, University of Otago, Dunedin, New Zealand
| | - Craig B Wilen
- Departments of Immunobiology and Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut
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4
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Sparrow K, Shrestha R, Wood JM, Clinch K, Hurst BL, Wang H, Gowen BB, Julander JG, Tarbet EB, McSweeney AM, Ward VK, Evans GB, Harris LD. An Isomer of Galidesivir That Potently Inhibits Influenza Viruses and Members of the Bunyavirales Order. ACS Med Chem Lett 2023; 14:506-513. [PMID: 37077387 PMCID: PMC10108398 DOI: 10.1021/acsmedchemlett.3c00048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023] Open
Abstract
We report for the first time the antiviral activities of two iminovirs (antiviral imino-C-nucleosides) 1 and 2, structurally related to galidesivir (Immucillin A, BCX4430). An iminovir containing the 4-aminopyrrolo[2,1-f][1,2,4-triazine] nucleobase found in remdesivir exhibited submicromolar inhibition of multiple strains of influenza A and B viruses, as well as members of the Bunyavirales order. We also report the first syntheses of ProTide prodrugs of iminovir monophosphates, which unexpectedly displayed poorer viral inhibition than their parent nucleosides in vitro. An efficient synthesis of the 4-aminopyrrolo[2,1-f][1,2,4-triazine]-containing iminovir 2 was developed to enable preliminary in vivo studies, wherein it displayed significant toxicity in BALB/c mice and limited protection against influenza. Further modification of this anti-influenza iminovir will therefore be required to improve its therapeutic value.
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Affiliation(s)
- Kevin
J. Sparrow
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
| | - Rinu Shrestha
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
- The
Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland 1142, New Zealand
| | - James M. Wood
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
- The
Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland 1142, New Zealand
| | - Keith Clinch
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
| | - Brett L. Hurst
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322-5600, United States
| | - Hong Wang
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322-5600, United States
| | - Brian B. Gowen
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322-5600, United States
| | - Justin G. Julander
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322-5600, United States
| | - E. Bart Tarbet
- Institute
for Antiviral Research, Utah State University, Logan, Utah 84322-5600, United States
| | - Alice M. McSweeney
- Department
of Microbiology & Immunology, University
of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Vernon K. Ward
- The
Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland 1142, New Zealand
- Department
of Microbiology & Immunology, University
of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Gary B. Evans
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
- The
Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland 1142, New Zealand
| | - Lawrence. D. Harris
- Ferrier
Research Institute, Victoria University
of Wellington, 69 Gracefield Road, Lower Hutt 5040, New Zealand
- The
Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland 1142, New Zealand
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5
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Mirabelli C, Jones MK, Young VL, Kolawole AO, Owusu I, Shan M, Abuaita B, Turula H, Trevino JG, Grigorova I, Lundy SK, Lyssiotis CA, Ward VK, Karst SM, Wobus CE. Human Norovirus Triggers Primary B Cell Immune Activation In Vitro. mBio 2022; 13:e0017522. [PMID: 35404121 PMCID: PMC9040803 DOI: 10.1128/mbio.00175-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 03/04/2022] [Indexed: 12/15/2022] Open
Abstract
Human norovirus (HNoV) is a global health and socioeconomic burden, estimated to infect every individual at least five times during their lifetime. The underlying mechanism for the potential lack of long-term immune protection from HNoV infections is not understood and prompted us to investigate HNoV susceptibility of primary human B cells and its functional impact. Primary B cells isolated from whole blood were infected with HNoV-positive stool samples and harvested at 3 days postinfection (dpi) to assess the viral RNA yield by reverse transcriptase quantitative PCR (RT-qPCR). A 3- to 18-fold increase in the HNoV RNA yield was observed in 50 to 60% of donors. Infection was further confirmed in B cells derived from splenic and lymph node biopsy specimens. Next, we characterized infection of whole-blood-derived B cells by flow cytometry in specific functional B cell subsets (naive CD27- IgD+, memory-switched CD27+ IgD-, memory-unswitched CD27+ IgD+, and double-negative CD27- IgD- cells). While the susceptibilities of the subsets were similar, changes in the B cell subset distribution upon infection were observed, which were also noted after treatment with HNoV virus-like particles and the predicted recombinant NS1 protein. Importantly, primary B cell stimulation with the predicted recombinant NS1 protein triggered B cell activation and induced metabolic changes. These data demonstrate that primary B cells are susceptible to HNoV infection and suggest that the NS1 protein can alter B cell activation and metabolism in vitro, which could have implications for viral pathogenesis and immune responses in vivo. IMPORTANCE Human norovirus (HNoV) is the most prevalent causative agent of gastroenteritis worldwide. Infection results in a self-limiting disease that can become chronic and severe in the immunocompromised, the elderly, and infants. There are currently no approved therapeutic and preventative strategies to limit the health and socioeconomic burdens associated with HNoV infections. Moreover, HNoV does not elicit lifelong immunity as repeat infections are common, presenting a challenge for vaccine development. Given the importance of B cells for humoral immunity, we investigated the susceptibility and impact of HNoV infection on human B cells. We found that HNoV replicates in human primary B cells derived from blood, spleen, and lymph node specimens, while the nonstructural protein NS1 can activate B cells. Because of the secreted nature of NS1, we put forward the hypothesis that HNoV infection can modulate bystander B cell function with potential impacts on systemic immune responses.
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Affiliation(s)
- Carmen Mirabelli
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Melissa K. Jones
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, USA
- Department of Microbiology and Cell Science, IFAS, University of Florida, Gainesville, Florida, USA
| | - Vivienne L. Young
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Abimbola O. Kolawole
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Irene Owusu
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
- West African Center for Cell Biology of Infectious Pathogens, Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana
| | - Mengrou Shan
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Basel Abuaita
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Holly Turula
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
- Graduate Program in Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Jose G. Trevino
- Division of Surgical Oncology, Department of Surgery, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Irina Grigorova
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
| | - Steven K. Lundy
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Costas A. Lyssiotis
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Vernon K. Ward
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Stephanie M. Karst
- Department of Molecular Genetics and Microbiology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Christiane E. Wobus
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
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6
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Eruera AR, McSweeney AM, McKenzie-Goldsmith GM, Ward VK. Protein Nucleotidylylation in +ssRNA Viruses. Viruses 2021; 13:1549. [PMID: 34452414 PMCID: PMC8402628 DOI: 10.3390/v13081549] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/30/2021] [Accepted: 08/02/2021] [Indexed: 12/22/2022] Open
Abstract
Nucleotidylylation is a post-transcriptional modification important for replication in the picornavirus supergroup of RNA viruses, including members of the Caliciviridae, Coronaviridae, Picornaviridae and Potyviridae virus families. This modification occurs when the RNA-dependent RNA polymerase (RdRp) attaches one or more nucleotides to a target protein through a nucleotidyl-transferase reaction. The most characterized nucleotidylylation target is VPg (viral protein genome-linked), a protein linked to the 5' end of the genome in Caliciviridae, Picornaviridae and Potyviridae. The nucleotidylylation of VPg by RdRp is a critical step for the VPg protein to act as a primer for genome replication and, in Caliciviridae and Potyviridae, for the initiation of translation. In contrast, Coronaviridae do not express a VPg protein, but the nucleotidylylation of proteins involved in replication initiation is critical for genome replication. Furthermore, the RdRp proteins of the viruses that perform nucleotidylylation are themselves nucleotidylylated, and in the case of coronavirus, this has been shown to be essential for viral replication. This review focuses on nucleotidylylation within the picornavirus supergroup of viruses, including the proteins that are modified, what is known about the nucleotidylylation process and the roles that these modifications have in the viral life cycle.
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Affiliation(s)
| | | | | | - Vernon K. Ward
- Department of Microbiology & Immunology, School of Biomedical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand; (A.-R.E.); (A.M.M.); (G.M.M.-G.)
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7
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McSweeney AM, Young VL, Ward VK. Norovirus VPg Binds RNA through a Conserved N-Terminal K/R Basic Patch. Viruses 2021; 13:v13071282. [PMID: 34209211 PMCID: PMC8310136 DOI: 10.3390/v13071282] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 06/23/2021] [Accepted: 06/26/2021] [Indexed: 11/17/2022] Open
Abstract
The viral protein genome-linked (VPg) of noroviruses is a multi-functional protein that participates in essential roles during the viral replication cycle. Predictive analyses indicate that murine norovirus (MNV) VPg contains a disordered N-terminal region with RNA binding potential. VPg proteins were expressed with an N-terminal spidroin fusion protein in insect cells and the interaction with RNA investigated by electrophoretic mobility shift assays (EMSA) against a series of RNA probes (pentaprobes) representing all possible five nucleotide combinations. MNV VPg and human norovirus (HuNV) VPg proteins were directly bound to RNA in a non-specific manner. To identify amino acids involved in binding to RNA, all basic (K/R) residues in the first 12 amino acids of MNV VPg were mutated to alanine. Removal of the K/R amino acids eliminated RNA binding and is consistent with a K/R basic patch RNA binding motif within the disordered N-terminal region of norovirus VPgs. Finally, we show that mutation of the K/R basic patch required for RNA binding eliminates the ability of MNV VPg to induce a G0/G1 cell cycle arrest.
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8
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Thomson NA, Howe L, Weidgraaf K, Thomas DG, Young V, Ward VK, Munday JS. Felis catus papillomavirus type 2 virus-like particle vaccine is safe and immunogenic but does not reduce FcaPV-2 viral loads in adult cats. Vet Immunol Immunopathol 2019; 213:109888. [PMID: 31307673 DOI: 10.1016/j.vetimm.2019.109888] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 05/04/2019] [Accepted: 06/26/2019] [Indexed: 02/03/2023]
Abstract
Felis catus papillomavirus type 2 (FcaPV-2) commonly infects the skin of domestic cats and has been associated with the development of skin cancer. In the present study, a FcaPV-2 virus-like particle (VLP) vaccine was produced and assessed for vaccine safety, immunogenicity, and impact on FcaPV-2 viral load. This is the first report of the use of a papillomavirus VLP vaccine in domestic cats. The FcaPV-2 VLP vaccine was given to ten adult cats that were naturally infected with FcaPV-2, and a further ten naturally infected cats were sham vaccinated as a control group. The rationale for vaccinating cats already infected with the virus was to induce neutralizing antibody titers that could prevent reinfection of new areas of skin and reduce the overall viral load, as has been demonstrated in other species. Reducing the overall FcaPV-2 viral load could reduce the risk for subsequent PV-associated cancer. The vaccine in this study was well-tolerated, as none of the cats developed any signs of local reaction or systemic illness. In the treatment group, the geometric mean anti-papillomavirus endpoint antibody titers increased significantly following vaccination from 606 (95% CI 192-1913) to 4223 (2023-8814), a 7.0-fold increase, although the individual antibody response varied depending on the level of pre-existing antibodies. Despite the immunogenicity of the vaccine, there was no significant change in FcaPV-2 viral load in the treatment group compared to the control group, over the 24 week follow-up period. A possible reason is that FcaPV-2 was already widespread in the basal skin layer of these adult cats and so preventing further cells from becoming infected had no impact on the overall viral load. Therefore, these results do not support the use of a FcaPV-2 VLP vaccine to reduce the risk for PV-associated cancer in cats in which FcaPV-2 infection is already well established. However, these results justify future studies in which the vaccine is administered to younger cats prior to FcaPV-2 infection becoming fully established.
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Affiliation(s)
- Neroli A Thomson
- School of Veterinary Science, Massey University, Palmerston North 4472, New Zealand.
| | - Laryssa Howe
- School of Veterinary Science, Massey University, Palmerston North 4472, New Zealand
| | - Karin Weidgraaf
- School of Agriculture and Environment, Massey University, Palmerston North 4472, New Zealand
| | - David G Thomas
- School of Agriculture and Environment, Massey University, Palmerston North 4472, New Zealand
| | - Vivienne Young
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9016, New Zealand
| | - John S Munday
- School of Veterinary Science, Massey University, Palmerston North 4472, New Zealand
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Kramer K, Braeden D, Young VL, Walker GF, Ward VK, Young SL. Abstract P4-06-20: Delivering tumour antigens survivin and mucin-1 on virus-like particles for breast cancer immunotherapy. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p4-06-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Breast cancer is the most frequently diagnosed cancer in women worldwide. Although there are a variety of treatment options available, breast cancer is a difficult disease to treat and many patients experience recurrence following treatment. We have previously shown that tumour antigens delivered on virus-like particles (VLP) induce a targeted anti-cancer immune response. In this study we investigated whether combining the two tumour antigens survivin and mucin 1 as vaccine targets can induce a superior anti-cancer immune response for breast cancer immunotherapy. VLP were designed to recombinantly express the murine survivin epitope. Following expression of Survivin-VLP, aberrantly glycosylated mucin 1 (MUC1) peptide was conjugated onto the Survivin-VLP using intracellular cleavable bis-arylhydrazone linking strategy. Western Blot analysis and electron microscopy confirmed Survivin-VLP expression and UV absorption confirmed conjugation of the MUC1 peptide to the Survivin-VLP. C57mg.MUC1 breast cancer cells were injected into the mammary fat pad of C57Bl/6 and MUC1 transgenic mice. Once tumours were palpable, mice were vaccinated with the Survivin-MUC1-VLP and controls of DPBS, VLP without antigen or VLP delivering either survivin or MUC1 antigen. Tumour growth and mouse survival were monitored for 80 days. Mice vaccinated with Survivin-MU1-VLP delivering both antigens showed enhanced survival (D78) compared to mice vaccinated with VLP delivering only one of the antigens (D66) and controls (D53). Delivery of two tumour antigens induced an enhanced anti-tumour immune response compared to delivery of single tumour antigens. The induction of multiple immune responses against different tumour antigens may apply additional evolutionary pressure upon tumours, prolonging the ability for tumours to develop resistance, or escape through the proliferation of a resistant subpopulation. The use of VLP for the delivery of multiple antigens and adjuvants represents a promising approach to improve cancer immunotherapy for breast cancer.
Citation Format: Kramer K, Braeden D, Young VL, Walker GF, Ward VK, Young SL. Delivering tumour antigens survivin and mucin-1 on virus-like particles for breast cancer immunotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-06-20.
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Affiliation(s)
- K Kramer
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - D Braeden
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - VL Young
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - GF Walker
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - VK Ward
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - SL Young
- Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; School of Biomedical Sciences, University of Otago, Dunedin, New Zealand; School of Pharmacy, University of Otago, Dunedin, New Zealand
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10
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Abstract
INTRODUCTION Virus-like particle (VLP) vaccines face significant challenges in their translation from laboratory models, to routine clinical administration. While some VLP vaccines thrive and are readily adopted into the vaccination schedule, others are restrained by regulatory obstacles, proprietary limitations, or finding their niche amongst the crowded vaccine market. Often the necessity to supplant an existing vaccination regimen possesses an immediate obstacle for the development of a VLP vaccine, despite any preclinical advantages identified over the competition. Novelty, adaptability and formulation compatibility may prove invaluable in helping place VLP vaccines at the forefront of vaccination technology. AREAS COVERED The purpose of this review is to outline the diversity of VLP vaccines, VLP-specific immune responses, and to explore how modern formulation and delivery techniques can enhance the clinical relevance and overall success of VLP vaccines. EXPERT COMMENTARY The role of formation science, with an emphasis on the diversity of immune responses induced by VLP, is underrepresented amongst clinical trials for VLP vaccines. Harnessing such diversity, particularly through the use of combinations of select excipients and adjuvants, will be paramount in the development of VLP vaccines.
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Affiliation(s)
- Braeden Donaldson
- a Department of Microbiology and Immunology , School of Biomedical Sciences, University of Otago , Dunedin , New Zealand.,b Department of Pathology , Dunedin School of Medicine, University of Otago , Dunedin , New Zealand
| | - Zabeen Lateef
- c Department of Pharmacology and Toxicology , School of Biomedical Sciences, University of Otago , Dunedin , New Zealand
| | - Greg F Walker
- d School of Pharmacy , University of Otago , Dunedin , New Zealand
| | - Sarah L Young
- b Department of Pathology , Dunedin School of Medicine, University of Otago , Dunedin , New Zealand
| | - Vernon K Ward
- a Department of Microbiology and Immunology , School of Biomedical Sciences, University of Otago , Dunedin , New Zealand
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Donaldson B, Al-Barwani F, Pelham SJ, Young K, Ward VK, Young SL. Multi-target chimaeric VLP as a therapeutic vaccine in a model of colorectal cancer. J Immunother Cancer 2017; 5:69. [PMID: 28806910 PMCID: PMC5556368 DOI: 10.1186/s40425-017-0270-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 07/21/2017] [Indexed: 02/08/2023] Open
Abstract
Background Colorectal cancer is responsible for almost 700,000 deaths annually worldwide. Therapeutic vaccination is a promising alternative to conventional treatment for colorectal cancer, using vaccines to induce targeted immune responses against tumour-associated antigens. In this study, we have developed chimaeric virus-like particles (VLP), a form of non-infectious non-replicative subunit vaccine consisting of rabbit haemorrhagic disease virus (RHDV) VP60 capsid proteins containing recombinantly inserted epitopes from murine topoisomerase IIα and survivin. These vaccines were developed in mono- (T.VP60, S.VP60) and multi-target (TS.VP60) forms, aiming to elucidate the potential benefits from multi-target vaccination. Methods Chimaeric RHDV VLP were developed by recombinantly inserting immune epitopes at the N-terminus of VP60. Vaccines were tested against a murine model of colorectal cancer by establishing MC38-OVA tumours subcutaneously. Unmethylated CpG DNA oligonucleotides (CpGs) were used as a vaccine adjuvant. Statistical tests employed included the Mantel-Cox log-rank test, ANOVA and unpaired t-tests depending on the data analysed, with a post hoc Bonferroni adjustment for multiple measures. Results Chimaeric RHDV VLP were found to form a composite particle in the presence of CpGs. Overall survival was significantly improved amongst mice bearing MC38-OVA tumours following vaccination with T.VP60 (60%, 9/15), S.VP60 (60%, 9/15) or TS.VP60 (73%, 11/15). TS.VP60 significantly prolonged the vaccine-induced remission period in comparison to each mono-therapy. Conclusions Chimaeric VLP containing multiple epitopes were found to confer an advantage for therapeutic vaccination in a model of colorectal cancer based on the prolongation of remission prior to tumour escape. Electronic supplementary material The online version of this article (doi:10.1186/s40425-017-0270-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Braeden Donaldson
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
| | - Farah Al-Barwani
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,Department of Pathology, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
| | - Simon J Pelham
- Department of Pathology, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
| | - Katie Young
- Department of Pathology, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Sarah L Young
- Department of Pathology, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand.
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12
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Lateef Z, Gimenez G, Baker ES, Ward VK. Transcriptomic analysis of human norovirus NS1-2 protein highlights a multifunctional role in murine monocytes. BMC Genomics 2017; 18:39. [PMID: 28056773 PMCID: PMC5217272 DOI: 10.1186/s12864-016-3417-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 12/12/2016] [Indexed: 12/22/2022] Open
Abstract
Background The GII.4 Sydney 2012 strain of human norovirus (HuNoV) is a pandemic strain that is responsible for the majority of norovirus outbreaks in healthcare settings. The function of the non-structural (NS)1-2 protein from HuNoV is unknown. Results In silico analysis of human norovirus NS1-2 protein showed that it shares features with the murine NS1-2 protein, including a disordered region, a transmembrane domain and H-box and NC sequence motifs. The proteins also contain caspase cleavage and phosphorylation sites, indicating that processing and phosphorylation may be a conserved feature of norovirus NS1-2 proteins. In this study, RNA transcripts of human and murine norovirus full-length and the disordered region of NS1-2 were transfected into monocytes, and next generation sequencing was used to analyse the transcriptomic profile of cells expressing virus proteins. The profiles were then compared to the transcriptomic profile of MNV-infected cells. Conclusions RNAseq analysis showed that NS1-2 proteins from human and murine noroviruses affect multiple immune systems (chemokine, cytokine, and Toll-like receptor signaling) and intracellular pathways (NFκB, MAPK, PI3K-Akt signaling) in murine monocytes. Comparison to the transcriptomic profile of MNV-infected cells indicated the pathways that NS1-2 may affect during norovirus infection. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3417-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zabeen Lateef
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, 720 Cumberland St, Dunedin, 9054, New Zealand.
| | - Gregory Gimenez
- Otago Genomics and Bioinformatics Facility, University of Otago, Dunedin, 9054, New Zealand
| | - Estelle S Baker
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, 720 Cumberland St, Dunedin, 9054, New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, 720 Cumberland St, Dunedin, 9054, New Zealand
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13
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Abstract
Murine norovirus-1 (MNV-1) is known to subvert host cell division inducing an accumulation of cells in the G0/G1 phase, creating conditions where viral replication is favored. This study identified that NS5 (VPg), is capable of inducing cell cycle arrest in the absence of viral replication or other viral proteins in an analogous manner to MNV-1 infection. NS5 expression induced an accumulation of cells in the G0/G1 phase in an asynchronous population by inhibiting progression at the G1/S restriction point. Furthermore, NS5 expression resulted in a down-regulation of cyclin A expression in asynchronous cells and inhibited cyclin A expression in cells progressing from G1 to S phase. The activity of NS5 on the host cell cycle occurs through an uncharacterized function. Amino acid substitutions of NS5(Y26A) and NS5(F123A) that inhibit the ability for NS5 to attach to RNA and recruit host eukaryotic translation initiation factors, respectively, retained the ability to induce an accumulation of cells in the G0/G1 phase as identified for wild-type NS5. To the best of our knowledge, this is the first report of a VPg protein manipulating the host cell cycle.
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Affiliation(s)
- Colin Davies
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, P. O. Box 56, Dunedin, 9054, New Zealand
| | - Vernon K. Ward
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, P. O. Box 56, Dunedin, 9054, New Zealand
- * E-mail:
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14
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Slatter TL, Wilson M, Tang C, Campbell HG, Ward VK, Young VL, Van Ly D, Fleming NI, Braithwaite AW, Baird MA. Antitumor cytotoxicity induced by bone-marrow-derived antigen-presenting cells is facilitated by the tumor suppressor protein p53 via regulation of IL-12. Oncoimmunology 2015; 5:e1112941. [PMID: 27141366 DOI: 10.1080/2162402x.2015.1112941] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 10/19/2015] [Accepted: 10/22/2015] [Indexed: 12/17/2022] Open
Abstract
Activated antigen-presenting cells (APC) deliver the three signals cytotoxic T cells require to differentiate into effector cells that destroy the tumor. These comprise antigen, co-stimulatory signals and cytokines. Once these cells have carried out their function, they apoptose. We hypothesized that the tumor suppressor protein, p53, played an important role in generating the antitumor response facilitated by APC. CD11c+ APC derived from p53 wild-type (wt) mouse (wt p53) GM-CSF bone marrow cultures (BMAPC) and activated had reduced survival compared to BMAPC from p53 null consistent with p53-mediated apoptosis following activation. There was a lower percentage of antigenic peptide/MHC I complexes on antigen-pulsed p53 null cells suggesting p53 played a role in antigen processing but there was no difference in antigen-specific T cell proliferative responses to these cells in vivo. In contrast, antigen-specific cytotoxicity in vivo was markedly reduced in response to p53 null BMAPC. When these cells were pulsed with a model tumor antigen and delivered as a prophylactic vaccination, they provided no protection against melanoma cell growth whereas wt BMAPC were very effective. This suggested that p53 might regulate the requisite third signal and, indeed, we found that p53 null BMAPC produced less IL-12 than wt p53 BMAPC and that p53 bound to the promoter region of IL-12. This work suggests that p53 in activated BMAPC is associated with the generation of IL-12 required for the differentiation of cytotoxic immune responses and an effective antitumor response. This is a completely new role for this protein that has implications for BMAPC-mediated immunotherapy.
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Affiliation(s)
- Tania L Slatter
- Department of Pathology, Dunedin School of Medicine, University of Otago , Dunedin, New Zealand
| | - Michelle Wilson
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Chingwen Tang
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago , Dunedin, New Zealand
| | - Hamish G Campbell
- Children's Medical Research Institute, University of Sydney , Westmead, Australia
| | - Vernon K Ward
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago , Dunedin, New Zealand
| | - Vivienne L Young
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago , Dunedin, New Zealand
| | - David Van Ly
- Children's Medical Research Institute, University of Sydney , Westmead, Australia
| | - Nicholas I Fleming
- Department of Pathology, Dunedin School of Medicine, University of Otago , Dunedin, New Zealand
| | - Antony W Braithwaite
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Children's Medical Research Institute, University of Sydney, Westmead, Australia; Maurice Wilkins Center, Auckland, New Zealand
| | - Margaret A Baird
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Maurice Wilkins Center, Auckland, New Zealand
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15
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Al-Barwani F, Young SL, Baird MA, Larsen DS, Ward VK. Mannosylation of virus-like particles enhances internalization by antigen presenting cells. PLoS One 2014; 9:e104523. [PMID: 25122183 PMCID: PMC4133192 DOI: 10.1371/journal.pone.0104523] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 07/11/2014] [Indexed: 12/05/2022] Open
Abstract
Internalization of peptides by antigen presenting cells is crucial for the initiation of the adaptive immune response. Mannosylation has been demonstrated to enhance antigen uptake through mannose receptors, leading to improved immune responses. In this study we test the effect of surface mannosylation of protein-based virus-like particles (VLP) derived from Rabbit hemorrhagic disease virus (RHDV) on uptake by murine and human antigen presenting cells. A monomannoside and a novel dimannoside were synthesized and successfully conjugated to RHDV VLP capsid protein, providing approximately 270 mannose groups on the surface of each virus particle. VLP conjugated to the mannoside or dimannoside exhibited significantly enhanced binding and internalization by murine dendritic cells, macrophages and B cells as well as human dendritic cells and macrophages. This uptake was inhibited by the inclusion of mannan as a specific inhibitor of mannose specific uptake, demonstrating that mannosylation of VLP targets mannose receptor-based uptake. Consistent with mannose receptor-based uptake, partial retargeting of the intracellular processing of RHDV VLP was observed, confirming that mannosylation of VLP provides both enhanced uptake and modified processing of associated antigens.
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Affiliation(s)
- Farah Al-Barwani
- Department of Microbiology and Immunology, Otago School of Medical Science, University of Otago, Dunedin, New Zealand
| | - Sarah L. Young
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Margaret A. Baird
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - David S. Larsen
- Department of Chemistry, Division of Sciences, University of Otago, Dunedin, New Zealand
| | - Vernon K. Ward
- Department of Microbiology and Immunology, Otago School of Medical Science, University of Otago, Dunedin, New Zealand
- * E-mail:
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16
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Herod MR, Salim O, Skilton RJ, Prince CA, Ward VK, Lambden PR, Clarke IN. Expression of the murine norovirus (MNV) ORF1 polyprotein is sufficient to induce apoptosis in a virus-free cell model. PLoS One 2014; 9:e90679. [PMID: 24599381 PMCID: PMC3944349 DOI: 10.1371/journal.pone.0090679] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 02/04/2014] [Indexed: 12/13/2022] Open
Abstract
Investigations into human norovirus infection, replication and pathogenesis, as well as the development of potential antiviral agents, have been restricted by the lack of a cell culture system for human norovirus. To date, the optimal cell culture surrogate virus model for studying human norovirus biology is the murine norovirus (MNV). In this report we generate a tetracycline-regulated, inducible eukaryotic cell system expressing the entire MNV ORF1 polyprotein. Once induced, the MNV ORF1 polyprotein was faithfully processed to the six mature non-structural proteins that predominately located to a discrete perinuclear region, as has been observed in active MNV infection. Furthermore, we found that expression of the ORF1 polyprotein alone was sufficient to induce apoptosis, characterised by caspase-9 activation and survivin down-regulation. This cell line provides a valuable new tool for studying MNV ORF1 non-structural protein function, screening for potential antiviral agents and acts as a proof-of-principle for such systems to be developed for human noroviruses.
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Affiliation(s)
- Morgan R. Herod
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
| | - Omar Salim
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
| | - Rachel J. Skilton
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
| | - Cynthia A. Prince
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
| | - Vernon K. Ward
- Otago School of Medical Sciences, Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Paul R. Lambden
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
| | - Ian N. Clarke
- Molecular Microbiology Group, University of Southampton, Southampton, United Kingdom
- * E-mail:
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17
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Waugh E, Chen A, Baird MA, Brown CM, Ward VK. Characterization of the chemokine response of RAW264.7 cells to infection by murine norovirus. Virus Res 2013; 181:27-34. [PMID: 24374268 DOI: 10.1016/j.virusres.2013.12.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 12/13/2013] [Accepted: 12/16/2013] [Indexed: 01/25/2023]
Abstract
Noroviruses are an emerging threat to public health, causing large health and economic costs, including at least 200,000 deaths annually. The inability to replicate in cell culture or small animal models has limited the understanding of the interaction between human noroviruses and their hosts. However, an alternative strategy to gain insights into norovirus pathogenesis is to study murine norovirus (MNV-1) that replicates in cultured macrophages. While the innate immune response is central to the resolution of norovirus disease, the adaptive immune response is required for viral clearance. The specific responses of macrophages and dendritic cells to infection drive the adaptive immune response, with chemokines playing an important role. In this study, we have conducted microarray analysis of RAW264.7 macrophages infected with MNV-1 and examined the changes in chemokine transcriptional expression during infection. While the majority of chemokines showed no change, there was specific up-regulation in chemokines reflective of a bias toward a Th1 response, specifically CCL2, CCL3, CCL4, CCL5, CXCL2, CXCL10 and CXCL11. These changes in gene expression were reflected in protein levels as determined by ELISA assay. This virus-induced chemokine response will affect the resolution of infection and may limit the humoral response to norovirus infection.
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Affiliation(s)
- Emily Waugh
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Augustine Chen
- Department of Biochemistry, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Margaret A Baird
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Chris M Brown
- Department of Biochemistry, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
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18
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Brown BM, Peiffer JJ, Taddei K, Lui JK, Laws SM, Gupta VB, Taddei T, Ward VK, Rodrigues MA, Burnham S, Rainey-Smith SR, Villemagne VL, Bush A, Ellis KA, Masters CL, Ames D, Macaulay SL, Szoeke C, Rowe CC, Martins RN, Martins RN. Physical activity and amyloid-β plasma and brain levels: results from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing. Mol Psychiatry 2013; 18:875-81. [PMID: 22889922 DOI: 10.1038/mp.2012.107] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 06/15/2012] [Accepted: 06/26/2012] [Indexed: 11/10/2022]
Abstract
Previous studies suggest physical activity improves cognition and lowers Alzheimer's disease (AD) risk. However, key AD pathogenic factors that are thought to be influenced by physical activity, particularly plasma amyloid-β (Aβ) and Aβ brain load, have yet to be thoroughly investigated. The objective of this study was to determine if plasma Aβ and amyloid brain deposition are associated with physical activity levels, and whether these associations differed between carriers and non-carriers of the apolipoprotein E (APOE) ε4 allele. Five-hundred and forty six cognitively intact participants (aged 60-95 years) from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) were included in these analyses. Habitual physical activity levels were measured using the International Physical Activity Questionnaire (IPAQ). Serum insulin, glucose, cholesterol and plasma Aβ levels were measured in fasting blood samples. A subgroup (n=116) underwent (11)C-Pittsburgh compound B (PiB) positron emission tomography (PET) scanning to quantify brain amyloid load. Higher levels of physical activity were associated with higher high density lipoprotein (HDL) (P=0.037), and lower insulin (P<0.001), triglycerides (P=0.019) and Aβ1-42/1-40 ratio (P=0.001). After stratification of the cohort based on APOE ε4 allele carriage, it was evident that only non-carriers received the benefit of reduced plasma Aβ from physical activity. Conversely, lower levels of PiB SUVR (standardised uptake value ratio) were observed in higher exercising APOE ε4 carriers. Lower plasma Aβ1-42/1-40 and brain amyloid was observed in those reporting higher levels of physical activity, consistent with the hypothesis that physical activity may be involved in the modulation of pathogenic changes associated with AD.
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Affiliation(s)
- B M Brown
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, WA, Australia
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Gardener S, Gu Y, Rainey-Smith SR, Keogh JB, Clifton PM, Mathieson SL, Taddei K, Mondal A, Ward VK, Scarmeas N, Barnes M, Ellis KA, Head R, Masters CL, Ames D, Macaulay SL, Rowe CC, Szoeke C, Martins RN. Adherence to a Mediterranean diet and Alzheimer's disease risk in an Australian population. Transl Psychiatry 2012; 2:e164. [PMID: 23032941 PMCID: PMC3565821 DOI: 10.1038/tp.2012.91] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The Mediterranean diet (MeDi), due to its correlation with a low morbidity and mortality for many chronic diseases, has been widely recognised as a healthy eating model. We aimed to investigate, in a cross-sectional study, the association between adherence to a MeDi and risk for Alzheimer's disease (AD) and mild cognitive impairment (MCI) in a large, elderly, Australian cohort. Subjects in the Australian Imaging, Biomarkers and Lifestyle Study of Ageing cohort (723 healthy controls (HC), 98 MCI and 149 AD participants) completed the Cancer Council of Victoria Food Frequency Questionnaire. Adherence to the MeDi (0- to 9-point scale with higher scores indicating higher adherence) was the main predictor of AD and MCI status in multinominal logistic regression models that were adjusted for cohort age, sex, country of birth, education, apolipoprotein E genotype, total caloric intake, current smoking status, body mass index, history of diabetes, hypertension, angina, heart attack and stroke. There was a significant difference in adherence to the MeDi between HC and AD subjects (P < 0.001), and in adherence between HC and MCI subjects (P < 0.05). MeDi is associated with change in Mini-Mental State Examination score over an 18-month time period (P < 0.05) in HCs. We conclude that in this Australian cohort, AD and MCI participants had a lower adherence to the MeDi than HC participants.
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Affiliation(s)
- S Gardener
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - Y Gu
- Taub Institute for Research of Alzheimer's Disease and the Ageing Brain, Columbia University, New York, NY, USA,Gertrude H. Sergievsky Centre, Columbia University, New York, NY, USA
| | - S R Rainey-Smith
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - J B Keogh
- School of Pharmacy and Medical Sciences and Sansom Institute for Health Research, Division of Health Sciences, University of South Australia, Adelaide, Australia
| | - P M Clifton
- Department of Medicine and Department of Biomedical Science, University of Adelaide, Adelaide, Australia,Nutritional Interventions, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - S L Mathieson
- Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - K Taddei
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - A Mondal
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - V K Ward
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia
| | - N Scarmeas
- Taub Institute for Research of Alzheimer's Disease and the Ageing Brain, Columbia University, New York, NY, USA,Gertrude H. Sergievsky Centre, Columbia University, New York, NY, USA,Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - M Barnes
- CSIRO, Preventative Health Flagship, Adelaide, Australia
| | - K A Ellis
- Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia,National Ageing Research Institute, Parkville, Victoria, Australia,Department of Psychiatry, Academic Unit for Psychiatry of Old Age, The University of Melbourne, St Vincent's Aged Psychiatry Service, St George's Hospital, Victoria, Australia
| | - R Head
- CSIRO, Preventative Health Flagship, Adelaide, Australia
| | - C L Masters
- Mental Health Research Institute, The University of Melbourne, Parkville, Victoria, Australia,Centre for Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - D Ames
- National Ageing Research Institute, Parkville, Victoria, Australia,Department of Psychiatry, Academic Unit for Psychiatry of Old Age, The University of Melbourne, St Vincent's Aged Psychiatry Service, St George's Hospital, Victoria, Australia
| | - S L Macaulay
- CSIRO Preventative Health Flagship, CMSE Parkville, Parkville, Victoria, Australia
| | - C C Rowe
- Department of Nuclear Medicine and Centre for PET, Austin Health, Heidelberg, Victoria, Australia
| | - C Szoeke
- CSIRO Preventative Health Flagship, CMSE Parkville, Parkville, Victoria, Australia
| | - R N Martins
- Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, Joondalup, Western Australia, Australia,Sir James McCusker Alzheimer's Disease Research Unit (Hollywood Private Hospital), Perth, Western Australia, Australia,Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical Sciences, Edith Cowan University, 270 Joondalup Drive, Joondalup, Western Australia 6027, Australia. E-mail:
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20
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Baker ES, Luckner SR, Krause KL, Lambden PR, Clarke IN, Ward VK. Inherent structural disorder and dimerisation of murine norovirus NS1-2 protein. PLoS One 2012; 7:e30534. [PMID: 22347381 PMCID: PMC3274520 DOI: 10.1371/journal.pone.0030534] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 12/23/2011] [Indexed: 11/28/2022] Open
Abstract
Human noroviruses are highly infectious viruses that cause the majority of acute, non-bacterial epidemic gastroenteritis cases worldwide. The first open reading frame of the norovirus RNA genome encodes for a polyprotein that is cleaved by the viral protease into six non-structural proteins. The first non-structural protein, NS1-2, lacks any significant sequence similarity to other viral or cellular proteins and limited information is available about the function and biophysical characteristics of this protein. Bioinformatic analyses identified an inherently disordered region (residues 1–142) in the highly divergent N-terminal region of the norovirus NS1-2 protein. Expression and purification of the NS1-2 protein of Murine norovirus confirmed these predictions by identifying several features typical of an inherently disordered protein. These were a biased amino acid composition with enrichment in the disorder promoting residues serine and proline, a lack of predicted secondary structure, a hydrophilic nature, an aberrant electrophoretic migration, an increased Stokes radius similar to that predicted for a protein from the pre-molten globule family, a high sensitivity to thermolysin proteolysis and a circular dichroism spectrum typical of an inherently disordered protein. The purification of the NS1-2 protein also identified the presence of an NS1-2 dimer in Escherichia coli and transfected HEK293T cells. Inherent disorder provides significant advantages including structural flexibility and the ability to bind to numerous targets allowing a single protein to have multiple functions. These advantages combined with the potential functional advantages of multimerisation suggest a multi-functional role for the NS1-2 protein.
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Affiliation(s)
- Estelle S. Baker
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
| | - Sylvia R. Luckner
- Department of Biochemistry, School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Kurt L. Krause
- Department of Biochemistry, School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Paul R. Lambden
- Molecular Microbiology and Infection, School of Medicine, University of Southampton, Southampton, United Kingdom
| | - Ian N. Clarke
- Molecular Microbiology and Infection, School of Medicine, University of Southampton, Southampton, United Kingdom
| | - Vernon K. Ward
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand
- * E-mail:
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21
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Win SJ, Ward VK, Dunbar PR, Young SL, Baird MA. Cross‐presentation of epitopes on virus‐like particles via the MHC I receptor recycling pathway. Immunol Cell Biol 2011; 89:681-8. [DOI: 10.1038/icb.2010.161] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Stephanie J Win
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago Dunedin New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago Dunedin New Zealand
| | - P Rod Dunbar
- School of Biological Sciences, University of Auckland Auckland New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland Auckland New Zealand
| | - Sarah L Young
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago Dunedin New Zealand
| | - Margaret A Baird
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago Dunedin New Zealand
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22
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Gatehouse HS, Poulton J, Markwick NP, Gatehouse LN, Ward VK, Young VL, Luo Z, Schaffer R, Christeller JT. Changes in gene expression in the permissive larval host lightbrown apple moth (Epiphyas postvittana, Tortricidae) in response to EppoNPV (Baculoviridae) infection. Insect Mol Biol 2009; 18:635-648. [PMID: 19754741 DOI: 10.1111/j.1365-2583.2009.00904.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Host cell and virus gene expression were measured five days after per os inoculation of 3rd instar lightbrown apple moth (LBAM) larvae with the Epiphyas postvittana nucleopolyhedrovirus (EppoNPV). Microarray analysis identified 84 insect genes that were up-regulated and 18 genes that were down-regulated in virus-infected larvae compared with uninfected larvae. From the 134 viral open reading frames represented on the microarray, 81 genes showed strong expression. Of the 38 functionally identifiable regulated insect genes, 23 coded for proteins that have roles in one of five processes; regulation of transcription and translation, induction of apoptosis, and maintenance of both juvenility and actin cytoskeletal integrity. Of the 34 functionally identifiable viral genes that were most strongly expressed, 12 had functions associated with these five processes, as did a further seven viral genes which were expressed at slightly lower levels. A survey of the LBAM-expressed sequence tag library identified further genes involved in these processes. In total, 135 insect genes and 38 viral genes were analysed by quantitative polymerase chain reaction. Twenty-one insect genes were strongly up-regulated and 31 genes strongly down-regulated. All 38 viral genes examined were highly expressed. These data suggest that induction of apoptosis and regulation of juvenility are the major 'battlegrounds' between virus and insect, with the majority of changes observed representing viral control of insect gene expression. Transcription and translational effects seem to be exerted largely through modulation of mRNA and protein degradation. Examples of attempts by the insect to repel the infection via changes in gene expression within these same processes were, however, also noted. The data also showed the extent to which viral transcription dominated in the infected insects at five days post inoculation.
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Affiliation(s)
- H S Gatehouse
- Plant and Food Research Institute, Palmerston North, New Zealand
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23
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Ward VK, Kalmakoff J. Physical mapping of the DNA genome of insect iridescent virus type 9 from Wiseana spp. larvae. Virology 2008; 160:507-10. [PMID: 18644576 DOI: 10.1016/0042-6822(87)90027-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/1987] [Accepted: 06/24/1987] [Indexed: 10/26/2022]
Abstract
A physical map for the DNA genome of insect iridescent virus type 9 isolated from Wiseana spp. larvae [Lepidoptera: Hepialidae] was constructed using the restriction enzymes BamHl, EcoRl, and Pstl. Viral DNA was cloned into the plasmids pBR328 and pUC8 using Escherichia coli strains HB101 and JM83, respectively. The physical map for BamHl, EcoRl, and Pstl was constructed by multiple enzyme analysis and Southern hybridization of cloned viral DNA. Statistical analysis of restriction data by computer-aided linear modeling supported the physical map produced and indicated a total genome size of 192.5 kb. Due to the cyclic permutation of iridescent virus genomes the map is presented in a circular form.
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Affiliation(s)
- V K Ward
- Department of Microbiology, University of Otago, P.O. Box 56, Dunedin, New Zealand
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24
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Wilson S, Baird M, Ward VK. Delivery of vaccine peptides by rapid conjugation to baculovirus particles. Vaccine 2008; 26:2451-6. [PMID: 18417258 DOI: 10.1016/j.vaccine.2008.03.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 03/07/2008] [Accepted: 03/12/2008] [Indexed: 02/06/2023]
Abstract
Baculoviruses deliver strong activation signals to dendritic cells and can promote potent immune responses. These properties can be harnessed to use baculovirus as an adjuvant and carrier particle for immunogenic peptides. In this study we use a chemical linker to couple peptides to the baculovirus Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). Intranasal delivery of baculovirus coupled with immunogenic peptides to mice elicited antigen-specific IgG1 and IgG2a antibody. Furthermore, antigen-specific IgA was detected in the lung, and an IFN-gamma response was observed upon re-stimulation with antigen. We show that chemical coupling enables the rapid modification of AcMNPV, allowing multiple epitopes to be delivered simultaneously on a self-adjuvanting carrier particle.
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Affiliation(s)
- Sarah Wilson
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
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25
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Peacey M, Wilson S, Baird MA, Ward VK. Versatile RHDV virus-like particles: incorporation of antigens by genetic modification and chemical conjugation. Biotechnol Bioeng 2008; 98:968-77. [PMID: 17546687 DOI: 10.1002/bit.21518] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Virus-like particles have proved to be excellent molecular scaffolds, yet the individual characteristics and immune responses generated against each VLP requires the development of a wide range of capsids for use as vaccines, molecular delivery vessels, and nanoscale templates. Here we describe the development of Rabbit haemorrhagic disease virus (RHDV)-like particles as a rapidly versatile molecular workbench, overcoming limitations imposed by established genetic antigen incorporation procedures with chimeric VLP. Production of the RHDV capsid protein in a baculovirus system led to the self-assembly of VLP which were recovered at over 99% purity and manipulated both genetically and chemically. Fusion of small peptide sequences to RHDV VLP was well tolerated, forming chimeric capsids that enhanced the presentation of foreign peptide to hybridoma T helper cells 700-fold. Rapid and simple conjugation techniques employing the hetero-bifunctional chemical linker sulfo-SMCC enabled both small peptides and whole proteins to be conjugated to the surface of RHDV VLP, overcoming limitations imposed on VLP formation and yield experienced with chimeric VLP. Administration of VLP/ovalbumin conjugate provoked high titre ovalbumin-specific antibody in mice, demonstrating the immune stimulatory properties of the capsid were conferred to conjugated foreign antigen. VLP facilitated delivery of conjugated antigen to dendritic cells, eliciting proliferative responses in naïve TCR transgenic T helper cells that were at least 10-fold greater than ovalbumin antigen delivered alone.
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MESH Headings
- Acyltransferases/chemistry
- Animals
- Antibody Formation/immunology
- Antigen Presentation/immunology
- Antigens/chemistry
- Antigens/genetics
- Antigens/immunology
- Antigens, Bacterial/chemistry
- Capsid/chemistry
- Capsid/immunology
- Capsid/ultrastructure
- Dendritic Cells/immunology
- Epitopes, T-Lymphocyte/chemistry
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Green Fluorescent Proteins/chemistry
- Hemagglutinins/chemistry
- Hemagglutinins/genetics
- Hemagglutinins/immunology
- Hemorrhagic Disease Virus, Rabbit/chemistry
- Hemorrhagic Disease Virus, Rabbit/genetics
- Lymphocyte Activation/immunology
- Maleimides/chemistry
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Microscopy, Immunoelectron
- Peptide Fragments/chemistry
- Peptide Fragments/genetics
- Peptide Fragments/immunology
- Rabbits
- Recombinant Proteins/chemistry
- Recombinant Proteins/immunology
- T-Lymphocytes/immunology
- Vaccination
- Vaccines, Synthetic/biosynthesis
- Vaccines, Synthetic/chemistry
- Vaccines, Synthetic/immunology
- Viral Structural Proteins/chemistry
- Viral Structural Proteins/genetics
- Viral Structural Proteins/immunology
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Affiliation(s)
- Matthew Peacey
- Department of Microbiology & Immunology, School of Medical Sciences, University of Otago, P.O. Box 56, Dunedin, 9054, New Zealand
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Ward VK, McCormick CJ, Clarke IN, Salim O, Wobus CE, Thackray LB, Virgin HW, Lambden PR. Recovery of infectious murine norovirus using pol II-driven expression of full-length cDNA. Proc Natl Acad Sci U S A 2007; 104:11050-5. [PMID: 17581883 PMCID: PMC1904157 DOI: 10.1073/pnas.0700336104] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Noroviruses are the major cause of nonbacterial gastroenteritis in humans. These viruses have remained refractory to detailed molecular studies because of the lack of a reverse genetics system coupled to a permissive cell line for targeted genetic manipulation. There is no permissive cell line in which to grow infectious human noroviruses nor an authentic animal model that supports their replication. In contrast, murine norovirus (MNV) offers a tractable system for the study of noroviruses with the recent discovery of permissive cells and a mouse model. The lack of a reverse genetic system for MNV has been a significant block to understanding the biology of noroviruses. We report recovery of infectious MNV after baculovirus delivery of viral cDNA to human hepatoma cells under the control of an inducible DNA polymerase (pol) II promoter. Recovered virus replicated in murine macrophage (RAW264.7) cells, and the recovery of MNV from DNA was confirmed through recovery of virus containing a marker mutation. This pol II promoter driven expression of viral cDNA also generated infectious virus after transfection of HEK293T cells, thus providing both transduction and transfection systems for norovirus reverse genetics. We used norovirus reverse genetics to demonstrate by mutagenesis of the protease-polymerase (pro-pol) cleavage site that processing of pro-pol is essential for the recovery of infectious MNV. This represents the first infectious reverse genetics system for a norovirus, and should provide approaches to address fundamental questions in norovirus molecular biology and replication.
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Affiliation(s)
- Vernon K Ward
- Department of Microbiology and Immunology, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand.
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27
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Barratt BIP, Murney R, Easingwood R, Ward VK. Virus-like particles in the ovaries of Microctonus aethiopoides Loan (Hymenoptera: Braconidae): comparison of biotypes from Morocco and Europe. J Invertebr Pathol 2005; 91:13-8. [PMID: 16375917 DOI: 10.1016/j.jip.2005.10.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 10/07/2005] [Accepted: 10/11/2005] [Indexed: 11/27/2022]
Abstract
Virus-like particles (MaVLP) have been discovered in the ovarial epithelial cells of the solitary, koinobiont, endoparasitoid, Microctonus aethiopoides Loan (Hymenoptera: Braconidae) introduced to New Zealand originally from Morocco to control the lucerne pest Sitona discoideus Gyllenhal (Coleoptera: Curculionidae). MaVLP have been found in all females examined. It has been suggested, although not demonstrated, that like many other such VLP found in parasitoids, MaVLP might play a role in host immunosuppression. Since another biotype of M. aethiopoides from Ireland has been proposed for introduction to control the white clover pest, Sitona lepidus Gyllenhal, in New Zealand, it was considered that females from this biotype warranted transmission electron microscope examination for VLP. No VLP were observed in ovarian tissues of specimens collected from three different locations in Ireland. Similarly, none were found in M. aethiopoides sourced from France, Wales, and Norway. These observations are discussed in relation to quarantine host specificity tests with the Irish biotype, which found that the host range of the Irish biotype is likely to be less extensive than that of the Moroccan biotype already in New Zealand.
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Affiliation(s)
- B I P Barratt
- AgResearch Invermay, Private Bag 50034, Mosgiel, New Zealand.
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Abstract
Baculovirus chitinases and other family 18 glycohydrolases have been shown to possess both exo- and endochitinase activities when assayed against fluorescent chito-oligosaccharides. Homology modelling of the chitinase ofEpiphyas postvittana nucleopolyhedrovirus(EppoNPV) againstSerratia marcescenschitinase A indicated that the enzyme possesses an N-terminal polycystic kidney 1 (PKD1) domain for chitin-substrate feeding and anα/βTIM barrel catalytic domain characteristic of a family 18 glycohydrolase. EppoNPV chitinase has many features in common with other baculovirus chitinases, including high amino acid identity, an N-terminal secretion signal and a functional C-terminal endoplasmic reticulum-retention sequence. EppoNPV chitinase displayed exo- and endochitinolytic activity against fluorescent chito-oligosaccharides, withKmvalues of 270±60 and 240±40 μM against 4MU-(GlcNAc)2and 20±6 and 14±7 μM against 4MU-(GlcNAc)3for native and recombinant versions of the enzyme, respectively. In contrast, digestion and thin-layer chromatography analysis of short-chain (GlcNAc)2–6chito-oligosaccharides without the fluorescent 4-methylumbelliferone (4MU) moiety produced predominantly (GlcNAc)2, indicating an exochitinase, although low-level endochitinase activity was detected. Digestion of long-chain colloidalβ-chitin and analysis by mass spectrometry identified a single 447 Da peak, representing a singly charged (GlcNAc)2complexed with a sodium adduct ion, confirming the enzyme as an exochitinase with no detectable endochitinolytic activity. Furthermore, (GlcNAc)3–6substrates, but not (GlcNAc)2, acted as inhibitors of EppoNPV chitinase. Short-chain substrates are unlikely to interact with the aromatic residues of the PKD1 substrate-feeding mechanism and hence may not accurately reflect the activity of these enzymes against native substrates. Based upon these results, the chitinase of the baculovirus EppoNPV is an exochitinase.
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Affiliation(s)
- Vivienne L Young
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand
| | - Robert M Simpson
- Horticulture and Food Research Institute of New Zealand, Palmerston North, New Zealand
| | - Vernon K Ward
- Department of Microbiology and Immunology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand
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Abstract
Chilo iridescent virus is demonstrated as a useful core substrate in the fabrication of metallodielectric, plasmonic nanostructures. A gold shell is assembled around the wild-type viral core by attaching small, 2-5-nm gold nanoparticles to the virus surface by means of the chemical functionality found inherently on the surface of the proteinaceous viral capsid. The density of these nucleation sites was maximized by reducing the repulsive forces between the gold particles through electrolyte addition. These gold nanoparticles then act as nucleation sites for the electroless deposition of gold ions from solution around the biotemplate. The optical extinction spectra of the metalloviral complex is in quantitative agreement with Mie scattering theory. Overall, the utilization of a native virus and the inherent chemical functionality of the capsid afford the ability to grow and harvest biotemplates for metallodielectric nanoshells in large quantities, potentially providing cores with a narrower size distribution and smaller diameters (below 80 nm) than for currently used silica.
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Affiliation(s)
- Corey Radloff
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson, Ohio, USA
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Mustard JA, Blenau W, Hamilton IS, Ward VK, Ebert PR, Mercer AR. Analysis of two D1-like dopamine receptors from the honey bee Apis mellifera reveals agonist-independent activity. Brain Res Mol Brain Res 2003; 113:67-77. [PMID: 12750008 DOI: 10.1016/s0169-328x(03)00091-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dopamine is found in many invertebrate organisms, including insects, however, the mechanisms through which this amine operates remain unclear. We have expressed two dopamine receptors cloned from honey bee (AmDOP1 and AmDOP2) in insect cells (Spodoptera frugiperda), and compared their pharmacology directly using production of cAMP as a functional assay. In each assay, AmDOP1 receptors required lower concentrations of dopamine and 6,7-ADTN for maximal activation than AmDOP2 receptors. Conversely, butaclamol and cis(Z)-flupentixol were more potent at blocking the cAMP response mediated through AmDOP2 than AmDOP1 receptors. Expression of AmDOP1, but not AmDOP2, receptors significantly increased levels of cAMP even in the absence of ligand. This constitutive activity was blocked by cis(Z)-flupentixol. This work provides the first evidence of a constitutively activated dopamine receptor in invertebrates and suggests that although AmDOP1 and AmDOP2 share much less homology than their vertebrate counterparts, they display a number of functional parallels with the mammalian D1-like dopamine receptors.
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Affiliation(s)
- Julie A Mustard
- Department of Zoology, P.O. Box 56, University of Otago, Dunedin, New Zealand
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Gorbalenya AE, Pringle FM, Zeddam JL, Luke BT, Cameron CE, Kalmakoff J, Hanzlik TN, Gordon KHJ, Ward VK. The palm subdomain-based active site is internally permuted in viral RNA-dependent RNA polymerases of an ancient lineage. J Mol Biol 2002; 324:47-62. [PMID: 12421558 PMCID: PMC7127740 DOI: 10.1016/s0022-2836(02)01033-1] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Template-dependent polynucleotide synthesis is catalyzed by enzymes whose core component includes a ubiquitous alphabeta palm subdomain comprising A, B and C sequence motifs crucial for catalysis. Due to its unique, universal conservation in all RNA viruses, the palm subdomain of RNA-dependent RNA polymerases (RdRps) is widely used for evolutionary and taxonomic inferences. We report here the results of elaborated computer-assisted analysis of newly sequenced replicases from Thosea asigna virus (TaV) and the closely related Euprosterna elaeasa virus (EeV), insect-specific ssRNA+ viruses, which revise a capsid-based classification of these viruses with tetraviruses, an Alphavirus-like family. The replicases of TaV and EeV do not have characteristic methyltransferase and helicase domains, and include a putative RdRp with a unique C-A-B motif arrangement in the palm subdomain that is also found in two dsRNA birnaviruses. This circular motif rearrangement is a result of migration of approximately 22 amino acid (aa) residues encompassing motif C between two internal positions, separated by approximately 110 aa, in a conserved region of approximately 550 aa. Protein modeling shows that the canonical palm subdomain architecture of poliovirus (ssRNA+) RdRp could accommodate the identified sequence permutation through changes in backbone connectivity of the major structural elements in three loop regions underlying the active site. This permutation transforms the ferredoxin-like beta1alphaAbeta2beta3alphaBbeta4 fold of the palm subdomain into the beta2beta3beta1alphaAalphaBbeta4 structure and brings beta-strands carrying two principal catalytic Asp residues into sequential proximity such that unique structural properties and, ultimately, unique functionality of the permuted RdRps may result. The permuted enzymes show unprecedented interclass sequence conservation between RdRps of true ssRNA+ and dsRNA viruses and form a minor, deeply separated cluster in the RdRp tree, implying that other, as yet unidentified, viruses may employ this type of RdRp. The structural diversification of the palm subdomain might be a major event in the evolution of template-dependent polynucleotide polymerases in the RNA-protein world.
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Key Words
- rna viruses
- rna polymerases
- evolution
- protein permutation
- ancient palm subdomain
- aa, amino acid
- cd, conserved domain
- eev, euprosterna elaeasa virus
- ibdv, infectious bursal disease virus
- ipnvj, infectious pancreatic necrosis virus strain jasper
- pv, poliovirus
- tav, thosea asigna virus
- dsrna, double-stranded rna
- ssrna+, positive-stranded rna
- rdrp, rna-dependent rna polymerase
- hmm, hidden markov model
- orf, open reading frames
- nt, nucleotide
- tdpp, template-dependent polynucleotide polymerase
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Affiliation(s)
- Alexander E Gorbalenya
- Advanced Biomedical Computing Center, Science Applications International Corporation/National Cancer Institute, P.O. Box B, Frederick, MD 21702-1201, USA.
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32
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Hyink O, Dellow RA, Olsen MJ, Caradoc-Davies KMB, Drake K, Herniou EA, Cory JS, O'Reilly DR, Ward VK. Whole genome analysis of the Epiphyas postvittana nucleopolyhedrovirus. J Gen Virol 2002; 83:957-971. [PMID: 11907346 DOI: 10.1099/0022-1317-83-4-957] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nucleotide sequence of the Epiphyas postvittana nucleopolyhedrovirus (EppoMNPV) genome has been determined and analysed. The circular dsDNA genome contains 118584 bp, making it the smallest group I NPV sequenced to date. The genome has a G+C content of 40.7% and encodes 136 predicted open reading frames (ORFs), five homologous repeat regions and one unique repeat region. Of the genome, 92.9% encodes predicted ORFs and 2.2% is in repeat regions; the remaining 4.9% of the genome comprises nonrepeat intergenic regions. EppoMNPV encodes homologues of 126 Orgyia pseudotsugata MNPV (OpMNPV) ORFs and 120 Autographa californica MNPV ORFs, with average identities of 64.7 and 53.5%, respectively. Between the four sequenced group I NPVs, 117 ORFs are conserved, whereas 86 ORFs are conserved between all fully sequenced NPVs. A total of 62 ORFs is present in all baculoviruses sequenced to date, with EppoMNPV lacking a homologue of the superoxide dismutase (sod) gene, which has been found in all other fully sequenced baculoviruses. Whole genome phylogenetic analyses of the ten fully sequenced baculoviruses using the sequences of the 62 shared genes, gene content and gene order data sets confirmed that EppoMNPV clusters tightly with OpMNPV in the group I NPVs. The main variation between EppoMNPV and OpMNPV occurs where extra clusters of genes are present in OpMNPV, with sod occurring in one such cluster. EppoMNPV encodes one truncated baculovirus repeated ORF (bro) gene. The only repeated ORFs are the four iap genes. Eight, randomly distributed, unique ORFs were identified on EppoMNPV, none of which show any significant homology to genes in GenBank.
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Affiliation(s)
- Otto Hyink
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Ross A Dellow
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Michael J Olsen
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Katherine M B Caradoc-Davies
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Kylie Drake
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Elisabeth A Herniou
- Ecology and Biocontrol Group, Centre for Ecology and Hydrology, Mansfield Road, Oxford OX1 3SR, UK3
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK2
| | - Jennifer S Cory
- Ecology and Biocontrol Group, Centre for Ecology and Hydrology, Mansfield Road, Oxford OX1 3SR, UK3
| | - David R O'Reilly
- Department of Biological Sciences, Imperial College of Science, Technology and Medicine, London SW7 2AZ, UK2
| | - Vernon K Ward
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
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Caradoc-Davies KM, Graves S, O'Reilly DR, Evans OP, Ward VK. Identification and in vivo characterization of the Epiphyas postvittana nucleopolyhedrovirus Ecdysteroid UDP-glucosyltransferase. Virus Genes 2001; 22:255-64. [PMID: 11450943 DOI: 10.1023/a:1011149819931] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The genome of Epiphyas postvittana Nucleopolyhedrovirus (EppoMNPV) contains an ecdysteroid UDP-glucosyltransferase (egt) gene. The egt gene was completely sequenced and surrounding open reading frames identified. EppoMNPV egt is 1479 nucleotides in length encoding a protein with a predicted molecular mass of 55 kDa. Analysis of upstream sequence revealed dual TATA boxes and two CGT upstream activating region motifs. Mapping of the 5' terminus of the egt transcript identified a major transcript produced from an adenine residue 29 nucleotides downstream from the distal TATA box. No transcript was detected from a late promoter motif (GTAAG). Characterization of egt transcripts showed that poly-adenylation occurs at the 3' terminus. EppoMNPV egt transcripts were first detected in infected Epiphyas postvittana larvae by Northern hybridization at 9 h post-infection (hpi) and EGT enzyme activity was detected at 9 hpi in haemolymph from infected larvae. EppoMNPV EGT can conjugate the sugars from both UDP-glucose and UDP-galactose to ecdysone in vitro. Localization assays performed using radiolabelled ecdysone demonstrated that the conjugation of glucose or galactose, from the respective UDP-sugar, led to the prevention of the uptake of ecdysone by SF-21 cells. We propose that EGT functions to prevent the uptake of ecdysone or 20-hydroxyecdysone by metabolite and target cells respectively.
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Brooks HJ, Mollison BD, Bettelheim KA, Matejka K, Paterson KA, Ward VK. Occurrence and virulence factors of non-O157 Shiga toxin-producing Escherichia coli in retail meat in Dunedin, New Zealand. Lett Appl Microbiol 2001; 32:118-22. [PMID: 11169055 DOI: 10.1046/j.1472-765x.2001.00868.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Retail raw meat was sampled for the presence of Shiga toxin-producing Escherichia coli (STEC) using enrichment culture and Vero cell assay. The STEC obtained were serotyped and tested for enterohaemolysin (Ehly) production and the eae gene. The presence of Shiga toxin genes (stx) was confirmed by polymerase chain reaction. A total of 18 STEC were isolated accounting for 12% of beef, 17% of lamb and 4% of pork samples. Five isolates produced Ehly but none possessed the eae gene. Five isolates were identified which possessed the stx2 gene and belonged to serotypes associated with severe infection.
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Affiliation(s)
- H J Brooks
- Department of Microbiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
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Pringle FM, Kalmakoff J, Ward VK. Analysis of the capsid processing strategy of Thosea asigna virus using baculovirus expression of virus-like particles. J Gen Virol 2001; 82:259-266. [PMID: 11125178 DOI: 10.1099/0022-1317-82-1-259] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Thosea asigna virus (TaV), a putative member of the genus Betatetravirus of the family Tetraviridae, is predicted to have a novel capsid expression strategy compared with other characterized tetraviruses. The capsid precursor protein is cleaved twice to generate three proteins. Two of the proteins, L (58.3 kDa) and S (6.8 kDa), are incorporated into the TaV virion. The third, non-structural protein, produced from the N terminus of the precursor protein, is up to 17 kDa in size and is of unknown function. The TaV capsid precursor protein sequence without the 17 kDa N-terminal region was modelled against the solved structure from Nudaurelia omega virus (N omega V) using SwissModel. The TaV model was very similar to the solved structure determined for subunit A of N omega V and had features that are conserved between tetraviruses and nodaviruses, including the positioning of the cleavage site between the L and S capsid proteins. The production of virus-like particles (VLPs) using the baculovirus expression system was used to analyse the capsid processing strategy employed by TaV. VLPs were formed in both the presence and absence of the 17 kDa N-terminal region of the capsid precursor. VLPs were not formed when the L and S regions were expressed from separate promoters, indicating that cleavage between the L and S capsid proteins was an essential part of TaV capsid assembly. Expression of the TaV 17 kDa protein in bacteria did not produce intracellular tubules similar to those formed by bacterial expression of the p17 protein from Helicoverpa armigera stunt virus.
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Affiliation(s)
- Fiona M Pringle
- Department of Microbiology, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - James Kalmakoff
- Department of Microbiology, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Vernon K Ward
- Department of Microbiology, University of Otago, PO Box 56, Dunedin, New Zealand1
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Abstract
In this study, four inhibitor of apoptosis genes (iaps) in the genome of Epiphyas postvittana nucleopolyhedrovirus (EppoMNPV) that are homologous to iap-1, iap-2, iap-3 and iap-4 genes of other baculoviruses have been identified. All four iap genes were sequenced and the iap-1 and iap-2 genes were shown to be functional inhibitors of apoptosis. The iap-1, iap-2 and iap-3 genes contain two baculovirus apoptosis inhibitor repeat motifs and a C(3)HC(4) RING finger-like motif. The activity of the iap genes was tested by transient expression in Spodoptera frugiperda (Sf-21) cells treated with the apoptosis-inducing agents actinomycin D, cycloheximide, anisomycin, tumour necrosis factor-alpha and UV light. The iap-2 gene prevented apoptosis induced by all agents tested, indicating activity towards a conserved component(s) of multiple apoptotic pathways. However, the iap-2 gene was unable to function in the absence of a gene immediately upstream of iap-2 that has homology to the orf69 gene of Autographa californica MNPV. The use of a CMV promoter rescued the apoptosis inhibition activity of the iap-2 gene, indicating that the upstream orf69 homologue is associated with expression of iap-2. The iap-1 gene was able to delay the onset of apoptosis caused by all of the induction agents tested but, unlike iap-2, was unable to prevent the development of an apoptotic response upon prolonged exposure of cells to the apoptosis induction agents. No anti-apoptotic activity was observed for the iap-3 and iap-4 genes of EppoMNPV.
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Affiliation(s)
- Terry Maguire
- Department of Microbiology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Penelope Harrison
- Department of Microbiology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Otto Hyink
- Department of Microbiology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - James Kalmakoff
- Department of Microbiology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
| | - Vernon K Ward
- Department of Microbiology, School of Medical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand1
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Abstract
Wiseana nucleopolyhedrovirus (NPV) is the major pathogen of the New Zealand endemic pasture pest, Wiseana spp. To characterize this potential biological control agent, the genome of a virus isolated from Wiseana signata was purified and cloned. The complete genome was cloned as BamHI or HindIII restriction fragments, which were mapped by Southern hybridization and restriction analysis. To verify the physical map, the junctions between all HindIII fragments were confirmed by sequencing. The viral genome was estimated to be 128 kbp. Sequence data generated at the termini of cloned restriction fragments were compared to sequence databases to identify putative gene homologues. Seventeen putative ORFs, which were homologous to other baculoviral sequences, were identified. These putative ORFs were located on the Wiseana NPV physical map and their distribution was compared to genetic maps of NPVs isolated from Autographa californica, Orgyia pseudotsugata and Lymantria dispar. Although the virus from W. signata was significantly different from these other NPVs, a core region of the viral genome was conserved.
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Affiliation(s)
- T J Sadler
- Department of Microbiology, School of Medical Sciences, Otago University, PO Box 56, Dunedin, New Zealand
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Pringle FM, Gordon KH, Hanzlik TN, Kalmakoff J, Scotti PD, Ward VK. A novel capsid expression strategy for Thosea asigna virus (Tetraviridae). J Gen Virol 1999; 80 ( Pt 7):1855-1863. [PMID: 10423156 DOI: 10.1099/0022-1317-80-7-1855] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This paper presents evidence that Thosea asigna virus (TaV) has a unique capsid expression strategy and is a member of the Nudaurelia beta-like genus of the Tetraviridae. Electron microscopy of TaV particles indicated a 38 nm, T = 4 icosahedral capsid similar in structure to that of Nudaurelia beta virus (NbetaV). TaV particles have a buoyant density of 1.296 g/cm3 in CsCl and consist of two capsid proteins of 56 and 6 kDa. The virus genome contains a genomic RNA molecule of 6.5 kb and a subgenomic molecule of 2.5 kb. Northern blotting of TaV RNA indicated a genomic organization similar to that of NbetaV. The capsid gene of TaV is carried on both the genomic and subgenomic RNA molecules, while the RNA polymerase gene is present only on the genomic RNA. Cloning and sequencing of the TaV capsid gene identified an open reading frame that could potentially encode a capsid precursor protein of up to 82.5 kDa. The N-terminal sequences of the capsid proteins were compared with the nucleotide sequence of the capsid open reading frame. The sequences indicate that the pre-protein is cleaved at two positions to produce the 56 and 6 kDa capsid proteins as well as a predicted third protein that was not detected in the mature virion. Phylogenetic analysis of the capsid proteins indicated that TaV is more closely related to NbetaV than to the Nudaurelia omega-like viruses. The eight beta-sheets that make up a jelly roll structure in the TaV capsid protein were identified by computer analysis.
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Abstract
The light brown apple moth, Epiphyas postvittana, is a major insect pest of a variety of fruit crops grown in New Zealand and we are studying a nucleopolyhedrovirus, EppoNPV, isolated from this insect. Restriction endonuclease analysis of EppoNPV DNA shows that this is a single strain of virus with a genome size of approximately 119 kbp and a complete library of the EppoNPV genome has been cloned. A strategy of single-stranded sequencing of the termini of REN fragment clones was employed to map the virus genome. Sequence homologies to NPV gene sequences present in the GenBank database allowed a nearly complete restriction map of the EppoNPV genome to be constructed. The mapping was completed with Southern blotting and restriction analysis. Fifty-five open reading frames (ORFs) with similarity to genes from other NPVs have been identified and placement of these on the restriction map shows that EppoNPV has a nearly identical genome organization to Orgyia pseudotsugata (Op)MNPV. The polyhedrin gene of EppoNPV has been fully sequenced and an ORF of 738 bp encodes a predicted protein of 28.8 kDa. The conserved 12 bp consensus sequence typical of very late baculovirus gene promoters, AATAAGTAATTT, has been located upstream of the ATG initiation codon. An ORF located downstream of the polyhedrin gene shows homology to the 1629-capsid protein from OpMNPV. Phylogenetic comparison to polyhedrin gene sequences from 23 other NPVs shows EppoNPV to be a group I NPV closely related to OpMNPV.
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Affiliation(s)
- O Hyink
- Department of Microbiology, University of Otago, Dunedin, New Zealand
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Bonning BC, Ward VK, van Meer MM, Booth TF, Hammock BD. Disruption of lysosomal targeting is associated with insecticidal potency of juvenile hormone esterase. Proc Natl Acad Sci U S A 1997; 94:6007-12. [PMID: 9177159 PMCID: PMC20991 DOI: 10.1073/pnas.94.12.6007] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Juvenile hormone esterase (JHE; EC 3.1.1.1), which is intrinsically involved in regulation of development of some insect larvae, is rapidly removed from the hemolymph by the pericardial cells. Lys-29 and Lys-524, which are implicated in the degradation of JHE, were mutated to Arg. Neither the half-life of the modified JHE in the hemolymph nor the catalytic parameters were changed significantly, but when combined, these mutations resulted in apparent failure of lysosomal targeting in the pericardial cell complex. A hypothesis for the mechanism of reduced efficiency of lysosomal targeting is presented. Infection of larvae with a recombinant baculovirus expressing the modified JHE resulted in a 50% reduction in feeding damage compared with larvae infected with the wild-type virus, thus demonstrating improved properties as a biological insecticide. These data demonstrate that alteration of specific residues of JHE that disrupted lysosomal targeting, dramatically increased the insecticidal activity of this protein.
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Affiliation(s)
- B C Bonning
- Department of Entomology, University of California, Davis, CA 95616, USA
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Abstract
We performed a systematic study of 55 solvent-producing clostridial strains, the majority of which are currently classified as Clostridium acetobutylicum strains, by using a combination of biotyping and DNA fingerprint analysis. The biotyping procedures used included rifampin susceptibility testing, bacteriocin typing, and bacteriophage typing. The 55 strains examined exhibited a good correlation between their biotypes and DNA fingerprints, which allowed us to divide them into nine groups. The DNA fingerprints of the nine groups differed markedly, but within each group the DNA fingerprints exhibited a high level of similarity. To determine the phylogenetic relationships of the nine groups, we performed a 16S rRNA gene sequence analysis. The results of a comparative analysis of the partial sequence corresponding to positions 830 to 1383 (Escherichia coli numbering) of the 16S rRNA gene indicated that the nine biotype groups could be assembled into four taxonomic groups. The complete 16S rRNA sequences of strains representing these groups were determined. Our phylogenetic analysis revealed that the amylolytic type strain C. acetobutylicum ATCC 824 (taxonomic group I) was only distantly related to the saccharolytic strains belonging to taxonomic groups II, III, and IV (levels of sequence similarity, 90 to 90.5%). The strains belonging to taxonomic groups II, III, and IV, represented by C. acetobutylicum NCP 262, "Clostridium saccharoperbutylacetonicum" N1-4, and C. acetobutylicum NCIMB 8052T (T = type strain), respectively, were closely related (levels of sequence similarity, 98.2 to 98.9%). C. acetobutylicum NCIMB 8052T exhibited a level of similarity of 100% with the type strain of Clostridium beijerinckii. Reclassification of the saccharolytic solvent-producing strains is necessary, and possible names for the four taxonomic groups are discussed.
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Affiliation(s)
- S Keis
- Department of Microbiology, University of Otago, Dunedin, New Zealand
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Abstract
The construction and screening of a small cDNA library consisting of 2 x 10(4) clones in the baculovirus expression vector system are described. This library consists of antibody heavy chain sequences isolated from the spleen of a mouse immunized with tetanus toxoid fragment C. A portion of this library was used to produce a pool of recombinant baculoviruses which were screened for production of antibody fragments reactive to tetanus toxoid without prior expression in Escherichia coli. The pool of 30 clones was found to contain at least 6 different populations of antibody indicating that diversity existed within the library. Positive clones were isolated from the baculovirus system and confirmed as being capable of producing a tetanus reactive antibody by expression as a beta-lactamase fusion protein in E. coli. One of these clones was returned to the baculovirus system using a different transfer vector, and tetanus binding reconfirmed. The results presented here show that the concept of the construction and screening of a baculovirus expression library is feasible even with 'difficult' proteins, such as antibody heavy chain fragments, and that the baculovirus expression vector system has the potential to produce cDNA expression libraries which can be screened directly for the desired protein.
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Affiliation(s)
- V K Ward
- Antibody Engineering Laboratory, University of California, Davis 95616, USA
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Kreissig SB, Ward VK, Hammock BD, Choudary PV. Nucleotide sequence of the variable region of the heavy and light chains of a monoclonal IgG antibody reactive to herbicides, terbutryn and prometryn. DNA Seq 1995; 6:51-4. [PMID: 8746462 DOI: 10.3109/10425179509074700] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Members of the triazine family of herbicides are reliable indicators of contamination of the ground water or soil with pesticide residues. To facilitate better detection of the chemical residues using improved immunoassay procedures, several monoclonal antibodies against triazine herbicides have been developed. K1F4 is a hybridoma secreting monoclonal (IgG) antibody reactive to terbutryn and prometryn, two members of the triazine family. We have cloned the genes encoding the variable regions of the heavy and light chains of this monoclonal antibody and report the nucleotide sequence here.
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Affiliation(s)
- S B Kreissig
- Antibody Engineering Laboratory and Department of Entomology, University of California, Davis, CA 95616 USA
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Harshman LG, Ward VK, Beetham JK, Grant DF, Grahan LJ, Zraket CA, Heckel DG, Hammock BD. Cloning, characterization, and genetics of the juvenile hormone esterase gene from Heliothis virescens. Insect Biochem Mol Biol 1994; 24:671-676. [PMID: 7915171 DOI: 10.1016/0965-1748(94)90054-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The gene for juvenile hormone esterase (JHE) was cloned from Heliothis virescens (Lepidoptera: Noctuidae). A genomic library was constructed from embryonic DNA and screened with a homologous N-terminal probe from the JHE cDNA. Five genomic clones were isolated and analyzed by dot blot hybridization using regions of the JHE cDNA as probes. Clone C hybridized to both 5' and 3' probes from the JHE cDNA, suggesting that clone C contains both ends of JHE gene. This was verified by sequencing the ends of the JHE gene from clone C using primers from both the 5' and 3' ends of the JHE cDNA. Additional sequencing and restriction mapping were used to characterize the gene. The gene is c. 8 kb long and contains four introns with consensus intron-exon junctions. One of the introns is relatively large (4 kb) and is situated near the extreme 5' end of the gene. Genetic analysis of RFLP variation in interspecific and intraspecific crosses shows that the JHE locus is single-copy with no closely related paralogs and is autosomally encoded in Heliothis. Therefore the developmental pattern of expression of this gene and the previously documented sequence variation in cDNA clones is not explainable by reference to a JHE gene family with distinct structural loci for the different forms.
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Affiliation(s)
- L G Harshman
- Department of Entomology, University of California, Davis 95616
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Ward VK, Hammock BD, Choudary PV. A microplate assay for the determination of protein deglycosylation. Biotechniques 1994; 16:1034-6. [PMID: 8074867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Affiliation(s)
- V K Ward
- Antibody Engineering Laboratory, University of California at Davis 95616
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Shiotsuki T, Huang TL, Uematsu T, Bonning BC, Ward VK, Hammock BD. Juvenile hormone esterase purified by affinity chromatography with 8-mercapto-1,1,1-trifluoro-2-octanone as a rationally designed ligand. Protein Expr Purif 1994; 5:296-306. [PMID: 7950375 DOI: 10.1006/prep.1994.1045] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Trifluoromethyl ketones are potent inhibitors of a variety of serine hydrolases. Based on this chemistry improved affinity chromatography procedures were developed for juvenile hormone esterase from insects. New affinity gels were prepared by binding rationally designed ligands to epoxy-activated Sepharose. One ligand is 8-mercapto-1,1,1-trifluoro-2-octanone which has a methylene group replacing a sulfide sulfur beta to the carbonyl of the trifluoromethyl ketone of the previously reported ligand, 3-(4-mercaptobutylthio)-1,1,1-trifluoro-2-propanone. With many loading levels and esterases, the original gel bound enzymes too tightly, resulting in elution difficulties. This replacement of the sulfur beta to the ketone thought to interact with the catalytic serine decreases the binding capacity of the gel at similar loading by approximately 56% compared to the affinity gel with the thioether. However, elution of the enzyme from the column can be accomplished with less potent inhibitors such as 3-n-butylthio- or 3-n-pentylthio-1,1,1-trifluoro-2-propanone, which can easily be removed from the enzyme by dialysis in the presence of the detergent n-octyl beta-D-glucopyranoside. An alternative approach allowing elution with less potent inhibitors involved varying concentrations of the previous high-affinity ligand to optimize the concentration of ligand on the column. Low concentrations of the high-affinity ligand also allowed the use of less potent eluting agents. These two improved affinity chromatography systems have been successfully used to purify juvenile hormone esterase of Heliothis virescens to near homogeneity with a 30-90% recovery of recombinant esterase secreted into the cell media in a baculovirus expression system. The purity of the esterase after affinity chromatography with newly prepared gel was comparable to that produced using the original affinity system based on analyses by SDS-PAGE and isoelectric focusing. A library of affinity gels with ligands of different affinities used at several loading levels and a library of eluting inhibitors of varying potency facilitate the rational selection of conditions for the affinity purification of esterases.
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Affiliation(s)
- T Shiotsuki
- Department of Entomology, University of California, Davis 95616
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Ward VK, Schneider PG, Kreissig SB, Hammock BD, Choudary PV. Cloning, sequencing and expression of the Fab fragment of a monoclonal antibody to the herbicide atrazine. Protein Eng 1993; 6:981-8. [PMID: 8309947 DOI: 10.1093/protein/6.8.981] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The Fab region of an IgG2b antibody (AM7B2.1) reactive to the herbicide atrazine was cloned into a plasmid vector using the polymerase chain reaction and two sets of degenerate oligonucleotide primers designed to mimic the amino acid variation at the N-termini of kappa L-chains and gamma H-chains. These primers also provide a secretion signal fused precisely to the antibody gene sequence for secretion of the mature antibody. A further set of universal oligonucleotide primers was developed for the direct sequencing of the VH and CH1 regions of gamma H-chains and the VL and CL regions of kappa L-chains without subcloning and were used to determine the sequence of this antibody. The kappa L-chain was found to not possess a conserved Cys residue at position 23 and the implications of this observation are discussed. The cloned genes were expressed in Escherichia coli using a commercially available T7 RNA polymerase-based plasmid. The clones were also expressed in a T7 RNA polymerase-based system containing an attenuated version of the T7 RNA polymerase promoter, plus a lac promoter placed in an antisense orientation, to enhance plasmid stability. The expressed products were confirmed as atrazine reactive by binding to an atrazine derivative conjugated with alkaline phosphatase.
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Affiliation(s)
- V K Ward
- UC Davis Antibody Engineering Laboratory
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Hammock BD, McCutchen BF, Beetham J, Choudary PV, Fowler E, Ichinose R, Ward VK, Vickers JM, Bonning BC, Harshman LG. Development of recombinant viral insecticides by expression of an insect-specific toxin and insect-specific enzyme in nuclear polyhedrosis viruses. Arch Insect Biochem Physiol 1993; 22:315-344. [PMID: 8467099 DOI: 10.1002/arch.940220303] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
As supplements to classical chemical insecticides, two approaches to develop recombinant baculovirus insecticides are described. In one approach an insect-specific toxin is expressed leading to a dramatic reduction in time to death. In the second approach an insect juvenile hormone esterase is expressed which leads to a reduction in feeding. Modifications of the wildtype esterase led to viruses which reduced the time to death as effectively as did the toxin-expressing virus. In both cases existing recombinant viruses are viewed as leads, and approaches to further improvement in the engineered viruses are suggested. Many of these approaches are based on analogy with the development of classical synthetic insecticides. Using these viruses as examples, the potential utility and limitations of recombinant viruses and other biological insecticides are discussed.
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Affiliation(s)
- B D Hammock
- Department of Entomology, University of California, Davis 95616
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Ward VK, Bonning BC, Huang T, Shiotsuki T, Griffeth VN, Hammock BD. Analysis of the catalytic mechanism of juvenile hormone esterase by site-directed mutagenesis. Int J Biochem 1992; 24:1933-41. [PMID: 1473606 DOI: 10.1016/0020-711x(92)90289-d] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. Juvenile hormone esterase (JHE) is a serine hydrolase selective for hydrolysis of the conjugated methyl esters of insect juvenile hormones. 2. We have investigated the mechanism of catalytic action of this enzyme by site-directed mutagenesis of the cloned enzyme and expression of the mutants in a baculovirus system. 3. A series of individual mutations of JHE were made to residues possibly involved in catalysis of juvenile hormones, and which are highly conserved in both esterases and lipases. 4. Mutation of the serine residue at position 201 to glycine (S201G), or aspartate 173 to asparagine (D173N), or histidine 446 to lysine (H446K), removed all detectable activity and these mutagenized enzymes were determined to be at least 10(6)-fold less active than wild type JHE. 5. Mutation of arginine 47 to histidine (R47H) decreased but did not abolish activity, with Km essentially unchanged at 66 nM for R47H compared to 34 nM for wild type JHE. 6. The kcat for R47H was decreased from 103 min-1 for wild type JHE to 1.9 min-1. 7. In addition, glutamate residue 332 was altered to glutamine (E332Q) and expressed in an Escherichia coli system. 8. This mutation was also found to remove all detectable activity. 9. From the results presented in this study and by comparison of JHE to other serine esterases and lipases, we predict that JHE possesses a Ser201-His446-Glu332 catalytic triad. 10. In addition, aspartate 173 and arginine 47 are essential for the efficient functioning of JHE.
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Affiliation(s)
- V K Ward
- Department of Entomology, University of California, Davis 95616
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Ward VK, Marriott AC, Polyzoni T, el-Ghorr AA, Antoniadis A, Nuttall PA. Expression of the nucleocapsid protein of Dugbe virus and antigenic cross-reactions with other nairoviruses. Virus Res 1992; 24:223-9. [PMID: 1529645 DOI: 10.1016/0168-1702(92)90009-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The small (S) RNA segment of Dugbe (DUG) virus (Nairovirus, Bunyaviridae) encodes a single protein, the nucleocapsid (N) protein, of M(r) 49.4 kDa. cDNA derived from the complete coding region for the N protein was cloned into Autographa californica nuclear polyhedrosis virus (AcNPV) under control of the polyhedrin promoter and used to infect Spodoptera frugiperda insect cells. Western blotting analysis using monoclonal antibodies demonstrated the production of DUG N protein in the infected cells. Monoclonal and polyclonal antibodies to the N protein of Crimean-Congo haemorrhagic fever (CCHF) virus were found to cross-react weakly with the baculovirus expressed DUG N protein by Western blotting. When used in an enzyme linked immunoassay (ELISA), the DUG N protein reacted with polyclonal mouse immune ascitic fluids raised against either CCHF or Hazara viruses (both members of the CCHF serogroup of nairoviruses). Cross-reactions between DUG virus (Nairobi sheep disease serogroup) and members of other nairovirus serogroups were not detected.
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Affiliation(s)
- V K Ward
- Department of Entomology, University of California, Davis 95616
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