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Mah SWL, Linklater DP, Tzanov V, Le PH, Dekiwadia C, Mayes E, Simons R, Eyckens DJ, Moad G, Saita S, Joudkazis S, Jans DA, Baulin VA, Borg NA, Ivanova EP. Piercing of the Human Parainfluenza Virus by Nanostructured Surfaces. ACS Nano 2024; 18:1404-1419. [PMID: 38127731 PMCID: PMC10902884 DOI: 10.1021/acsnano.3c07099] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
This paper presents a comprehensive experimental and theoretical investigation into the antiviral properties of nanostructured surfaces and explains the underlying virucidal mechanism. We used reactive ion etching to fabricate silicon (Si) surfaces featuring an array of sharp nanospikes with an approximate tip diameter of 2 nm and a height of 290 nm. The nanospike surfaces exhibited a 1.5 log reduction in infectivity of human parainfluenza virus type 3 (hPIV-3) after 6 h, a substantially enhanced efficiency, compared to that of smooth Si. Theoretical modeling of the virus-nanospike interactions determined the virucidal action of the nanostructured substrata to be associated with the ability of the sharp nanofeatures to effectively penetrate the viral envelope, resulting in the loss of viral infectivity. Our research highlights the significance of the potential application of nanostructured surfaces in combating the spread of viruses and bacteria. Notably, our study provides valuable insights into the design and optimization of antiviral surfaces with a particular emphasis on the crucial role played by sharp nanofeatures in maximizing their effectiveness.
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Affiliation(s)
- Samson W L Mah
- School of Science, STEM College, RMIT University, Melbourne, Victoria 3000, Australia
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | - Denver P Linklater
- School of Science, STEM College, RMIT University, Melbourne, Victoria 3000, Australia
- Department of Biomedical Engineering, Graeme Clarke Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Vassil Tzanov
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n, Tarragona 43007, Spain
| | - Phuc H Le
- School of Science, STEM College, RMIT University, Melbourne, Victoria 3000, Australia
| | - Chaitali Dekiwadia
- RMIT Microscopy and Microanalysis Facility, STEM College,RMIT University, Melbourne, Victoria 3000, Australia
| | - Edwin Mayes
- RMIT Microscopy and Microanalysis Facility, STEM College,RMIT University, Melbourne, Victoria 3000, Australia
| | - Ranya Simons
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | | | - Graeme Moad
- CSIRO Manufacturing, Clayton, Victoria 3168, Australia
| | - Soichiro Saita
- The KAITEKI Institute Inc., Chiyoda-ku, Tokyo 100-8251, Japan
| | - Saulius Joudkazis
- Optical Science Centre, Swinburne University of Technology, Hawthorn, Melbourne, Victoria 3122, Australia
| | - David A Jans
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Monash, Victoria 3800, Australia
| | - Vladimir A Baulin
- Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n, Tarragona 43007, Spain
| | - Natalie A Borg
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria 3083, Australia
| | - Elena P Ivanova
- School of Science, STEM College, RMIT University, Melbourne, Victoria 3000, Australia
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Martin AJ, Shackleford DM, Charman SA, Wagstaff KM, Porter CJH, Jans DA. Increased In Vivo Exposure of N-(4-Hydroxyphenyl) Retinamide (4-HPR) to Achieve Plasma Concentrations Effective against Dengue Virus. Pharmaceutics 2023; 15:1974. [PMID: 37514160 PMCID: PMC10384639 DOI: 10.3390/pharmaceutics15071974] [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: 06/13/2023] [Revised: 07/11/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
N-(4-hydroxyphenyl) retinamide (4-HPR, or fenretinide) has promising in vitro and in vivo antiviral activity against a range of flaviviruses and an established safety record, but there are challenges to its clinical use. This study evaluated the in vivo exposure profile of a 4-HPR dosage regime previously shown to be effective in a mouse model of severe dengue virus (DENV) infection, comparing it to an existing formulation for human clinical use for other indications and developed/characterised self-emulsifying lipid-based formulations of 4-HPR to enhance 4-HPR in vivo exposure. Pharmacokinetic (PK) analysis comprising single-dose oral and IV plasma concentration-time profiles was performed in mice; equilibrium solubility testing of 4-HPR in a range of lipids, surfactants and cosolvents was used to inform formulation approaches, with lead formulation candidates digested in vitro to analyse solubilisation/precipitation prior to in vivo testing. PK analysis suggested that effective plasma concentrations could be achieved with the clinical formulation, while novel lipid-based formulations achieved > 3-fold improvement. Additionally, 4-HPR exposure was found to be limited by both solubility and first-pass intestinal elimination but could be improved through inhibition of cytochrome P450 (CYP) metabolism. Simulated exposure profiles suggest that a b.i.d dosage regime is likely to maintain 4-HPR above the minimum effective plasma concentration for anti-DENV activity using the clinical formulation, with new formulations/CYP inhibition viable options to increase exposure in the future.
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Affiliation(s)
- Alexander J Martin
- Nuclear Signalling Laboratory, Department Biochem. & Mol. Biol., Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
| | - David M Shackleford
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Susan A Charman
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - Kylie M Wagstaff
- Nuclear Signalling Laboratory, Department Biochem. & Mol. Biol., Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
| | - Christopher J H Porter
- Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Victoria, Australia
| | - David A Jans
- Nuclear Signalling Laboratory, Department Biochem. & Mol. Biol., Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
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Hu M, Bogoyevitch MA, Jans DA. Respiratory Syncytial Virus Matrix Protein Is Sufficient and Necessary to Remodel Host Mitochondria in Infection. Cells 2023; 12:cells12091311. [PMID: 37174711 PMCID: PMC10177070 DOI: 10.3390/cells12091311] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/24/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
Although respiratory syncytial virus (RSV) is the most common cause of respiratory infection in infants, immunosuppressed adults and the elderly worldwide, there is no licensed RSV vaccine or widely applicable antiviral therapeutics We previously reported a staged redistribution of mitochondria with compromised respiratory activities and increased reactive oxygen species (ROS) generation during RSV infection. Here, we show for the first time that the RSV matrix protein (M) is sufficient and necessary to induce these effects. Ectopically expressed M, but not other RSV proteins, was able to induce mitochondrial perinuclear clustering, inhibition of mitochondrial respiration, loss of mitochondrial membrane potential (Δψm), and enhanced generation of mitochondrial ROS (mtROS) in infection. Truncation and mutagenic analysis revealed that the central nucleic acid-binding domain of M is essential for the effects on host mitochondria, with arginine/lysine residues 170/172 being critically important. Recombinant RSV carrying the arginine/lysine mutations in M was unable to elicit effects on host mitochondria. Further, wild-type but not mutant RSV was found to inhibit the mRNA expression of genes encoding mitochondrial proteins, including Complex I subunits. Importantly, the RSV mutant was impaired in virus production, underlining the importance of M-dependent effects on mitochondria to RSV infection. Together, our results highlight M's unique ability to remodel host cell mitochondria and its critical role in RSV infection, representing a novel, potential target for future anti-RSV strategies.
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Affiliation(s)
- MengJie Hu
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC 3800, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC 3800, Australia
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Walunj SB, Wang C, Wagstaff KM, Patankar S, Jans DA. Conservation of Importin α Function in Apicomplexans: Ivermectin and GW5074 Target Plasmodium falciparum Importin α and Inhibit Parasite Growth in Culture. Int J Mol Sci 2022; 23:ijms232213899. [PMID: 36430384 PMCID: PMC9695642 DOI: 10.3390/ijms232213899] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/03/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
Signal-dependent transport into and out of the nucleus mediated by members of the importin (IMP) superfamily of nuclear transporters is critical to the eukaryotic function and a point of therapeutic intervention with the potential to limit disease progression and pathogenic outcomes. Although the apicomplexan parasites Plasmodium falciparum and Toxoplasma gondii both retain unique IMPα genes that are essential, a detailed analysis of their properties has not been performed. As a first step to validate apicomplexan IMPα as a target, we set out to compare the properties of P. falciparum and T. gondii IMPα (PfIMPα and TgIMPα, respectively) to those of mammalian IMPα, as exemplified by Mus musculus IMPα (MmIMPα). Close similarities were evident, with all three showing high-affinity binding to modular nuclear localisation signals (NLSs) from apicomplexans as well as Simian virus SV40 large tumour antigen (T-ag). PfIMPα and TgIMPα were also capable of binding to mammalian IMPβ1 (MmIMPβ1) with high affinity; strikingly, NLS binding by PfIMPα and TgIMPα could be inhibited by the mammalian IMPα targeting small molecules ivermectin and GW5074 through direct binding to PfIMPα and TgIMPα to perturb the α-helical structure. Importantly, GW5074 could be shown for the first time to resemble ivermectin in being able to limit growth of P. falciparum. The results confirm apicomplexan IMPα as a viable target for the development of therapeutics, with agents targeting it worthy of further consideration as an antimalarial.
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Affiliation(s)
- Sujata B. Walunj
- Molecular Parasitology Lab., Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Monash, VIC 3800, Australia
| | - Chunxiao Wang
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Monash, VIC 3800, Australia
| | - Kylie M. Wagstaff
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Monash, VIC 3800, Australia
| | - Swati Patankar
- Molecular Parasitology Lab., Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - David A. Jans
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Monash, VIC 3800, Australia
- Correspondence:
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Ghildyal R, Teng MN, Tran KC, Mills J, Casarotto MG, Bardin PG, Jans DA. Nuclear Transport of Respiratory Syncytial Virus Matrix Protein Is Regulated by Dual Phosphorylation Sites. Int J Mol Sci 2022; 23:ijms23147976. [PMID: 35887322 PMCID: PMC9317576 DOI: 10.3390/ijms23147976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 05/30/2022] [Revised: 07/02/2022] [Accepted: 07/06/2022] [Indexed: 02/04/2023] Open
Abstract
Respiratory syncytial virus (RSV) is a major cause of respiratory infections in infants and the elderly. Although the RSV matrix (M) protein has key roles in the nucleus early in infection, and in the cytoplasm later, the molecular basis of switching between the nuclear and cytoplasmic compartments is not known. Here, we show that protein kinase CK2 can regulate M nucleocytoplasmic distribution, whereby inhibition of CK2 using the specific inhibitor 4,5,6,7-tetrabromobenzo-triazole (TBB) increases M nuclear accumulation in infected cells as well as when ectopically expressed in transfected cells. We use truncation/mutagenic analysis for the first time to show that serine (S) 95 and threonine (T) 205 are key CK2 sites that regulate M nuclear localization. Dual alanine (A)-substitution to prevent phosphorylation abolished TBB- enhancement of nuclear accumulation, while aspartic acid (D) substitution to mimic phosphorylation at S95 increased nuclear accumulation. D95 also induced cytoplasmic aggregate formation, implying that a negative charge at S95 may modulate M oligomerization. A95/205 substitution in recombinant RSV resulted in reduced virus production compared with wild type, with D95/205 substitution resulting in an even greater level of attenuation. Our data support a model where unphosphorylated M is imported into the nucleus, followed by phosphorylation of T205 and S95 later in infection to facilitate nuclear export and cytoplasmic retention of M, respectively, as well as oligomerization/virus budding. In the absence of widely available, efficacious treatments to protect against RSV, the results raise the possibility of antiviral strategies targeted at CK2.
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Affiliation(s)
- Reena Ghildyal
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra 2617, Australia
- Correspondence: ; Tel.: +612-6201-5755
| | - Michael N. Teng
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (M.N.T.); (K.C.T.)
| | - Kim C. Tran
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (M.N.T.); (K.C.T.)
| | - John Mills
- Faculty of Medicine, Monash University, Burnet Institute for Medical Research, The Alfred Hospital Department of Infectious Diseases, Melbourne 3004, Australia;
| | - Marco G. Casarotto
- Research School of Biology, Australian National University, Canberra 2601, Australia;
| | - Philip G. Bardin
- Monash Lung & Sleep and Hudson Institute, Monash University, Melbourne 3181, Australia;
| | - David A. Jans
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash University, Melbourne 3181, Australia;
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Gajewska KA, Ramialison M, Wagstaff KM, Jans DA. Transcriptomic profile dataset of embryonic stem cells (Wild-type and IPO13-Knock Out) with and without oxidative stress. Data Brief 2022; 42:108099. [PMID: 35434231 PMCID: PMC9010623 DOI: 10.1016/j.dib.2022.108099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 03/13/2022] [Accepted: 03/21/2022] [Indexed: 11/30/2022] Open
Abstract
The transcriptional response to cellular stress relies upon trafficking of regulators of transcription between the nuclear and cytoplasmic compartments, which occurs through action of members of the importin (IPO) superfamily. As a result of stresses such as oxidative or osmotic stress, one consequence is that importins become mislocalised, leading to inhibition of conventional nuclear transport. Here, we examine IPO13, which has a number of nonconventional characteristics, in the context of cell stress. We used Next Generation RNA Sequencing using the Illumina platform to compare the transcriptomes of Wild-type (WT) and IPO13-Knockout (KO) mouse embryonic stem cells in the absence and presence of oxidative stress. Differences in the mRNA expression profiles were observed between the cell lines in the absence and in the presence of stress. This data will be a key resource to enable characterization of the contribution of nuclear transporter IPO13 to cellular transcription in the absence and presence of oxidative stress, as well as more broadly, in the study of stem cell biology and effect of stress on embryonic stem cell transcription.
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Affiliation(s)
| | - Mirana Ramialison
- Australian Regenerative Medicine Institute and Systems Biology Institute, Monash University, Clayton, VIC, Australia
| | - Kylie M. Wagstaff
- Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - David A. Jans
- Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Corresponding author.
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Yang SNY, Maher B, Wang C, Wagstaff KM, Fraser JE, Jans DA. High Throughput Screening Targeting the Dengue NS3-NS5 Interface Identifies Antivirals against Dengue, Zika and West Nile Viruses. Cells 2022; 11:730. [PMID: 35203378 PMCID: PMC8870125 DOI: 10.3390/cells11040730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 12/27/2021] [Revised: 02/03/2022] [Accepted: 02/11/2022] [Indexed: 12/04/2022] Open
Abstract
Dengue virus (DENV) threatens almost 70% of the world's population, with no effective therapeutic currently available and controversy surrounding the one approved vaccine. A key factor in dengue viral replication is the interaction between DENV nonstructural proteins (NS) 5 and 3 (NS3) in the infected cell. Here, we perform a proof-of-principle high-throughput screen to identify compounds targeting the NS5-NS3 binding interface. We use a range of approaches to show for the first time that two small molecules-repurposed drugs I-OMe tyrphostin AG538 (I-OMe-AG238) and suramin hexasodium (SHS)-inhibit NS5-NS3 binding at low μM concentration through direct binding to NS5 that impacts thermostability. Importantly, both have strong antiviral activity at low μM concentrations against not only DENV-2, but also Zika virus (ZIKV) and West Nile virus (WNV). This work highlights the NS5-NS3 binding interface as a viable target for the development of anti-flaviviral therapeutics.
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Affiliation(s)
| | | | | | | | | | - David A. Jans
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Monash, VIC 3800, Australia; (S.N.Y.Y.); (B.M.); (C.W.); (K.M.W.); (J.E.F.)
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Lee A, Bogoyevitch MA, Jans DA. Bimolecular Fluorescence Complementation: Quantitative Analysis of In Cell Interaction of Nuclear Transporter Importin α with Cargo Proteins. Methods Mol Biol 2022; 2502:215-233. [PMID: 35412241 DOI: 10.1007/978-1-0716-2337-4_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 06/14/2023]
Abstract
Bimolecular fluorescence complementation utilizes the ability of two complementary nonfluorescent fragments to reconstitute and emit fluorescence when brought together through specific interaction of attached protein fragments of interest. It has been used in several different contexts to study protein-protein interaction. Here we apply the method for the first time to study interaction of the nuclear transporter importin α and its cargoes in a cellular context. By using image analysis to quantify the extent of nuclear complexation, it is possible to gain insight into the strength of interaction in cells.
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Affiliation(s)
- Alexander Lee
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia
| | - David A Jans
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia.
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia.
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Li HM, Ghildyal R, Hu M, Tran KC, Starrs LM, Mills J, Teng MN, Jans DA. Respiratory Syncytial Virus Matrix Protein-Chromatin Association Is Key to Transcriptional Inhibition in Infected Cells. Cells 2021; 10:2786. [PMID: 34685766 PMCID: PMC8534903 DOI: 10.3390/cells10102786] [Citation(s) in RCA: 9] [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: 07/27/2021] [Revised: 09/23/2021] [Accepted: 10/06/2021] [Indexed: 01/07/2023] Open
Abstract
The morbidity and mortality caused by the globally prevalent human respiratory pathogen respiratory syncytial virus (RSV) approaches that world-wide of influenza. We previously demonstrated that the RSV matrix (M) protein shuttles, in signal-dependent fashion, between host cell nucleus and cytoplasm, and that this trafficking is central to RSV replication and assembly. Here we analyze in detail the nuclear role of M for the first time using a range of novel approaches, including quantitative analysis of de novo cell transcription in situ in the presence or absence of RSV infection or M ectopic expression, as well as in situ DNA binding. We show that M, dependent on amino acids 110-183, inhibits host cell transcription in RSV-infected cells as well as cells transfected to express M, with a clear correlation between nuclear levels of M and the degree of transcriptional inhibition. Analysis of bacterially expressed M protein and derivatives thereof mutated in key residues within M's RNA binding domain indicates that M can bind to DNA as well as RNA in a cell-free system. Parallel results for point-mutated M derivatives implicate arginine 170 and lysine 172, in contrast to other basic residues such as lysine 121 and 130, as critically important residues for inhibition of transcription and DNA binding both in situ and in vitro. Importantly, recombinant RSV carrying arginine 170/lysine 172 mutations shows attenuated infectivity in cultured cells and in an animal model, concomitant with altered inflammatory responses. These findings define an RSV M-chromatin interface critical for host transcriptional inhibition in infection, with important implications for anti-RSV therapeutic development.
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Affiliation(s)
- Hong-Mei Li
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Melbourne, VIC 3800, Australia; (H.-M.L.); (R.G.); (M.H.)
| | - Reena Ghildyal
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Melbourne, VIC 3800, Australia; (H.-M.L.); (R.G.); (M.H.)
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT 2617, Australia;
| | - Mengjie Hu
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Melbourne, VIC 3800, Australia; (H.-M.L.); (R.G.); (M.H.)
| | - Kim C. Tran
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (K.C.T.); (M.N.T.)
| | - Lora M. Starrs
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, ACT 2617, Australia;
| | - John Mills
- Department of Infectious Diseases, School of Biomedical Sciences, Monash University and the Burnet Institute, Melbourne, VIC 3004, Australia;
| | - Michael N. Teng
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; (K.C.T.); (M.N.T.)
| | - David A. Jans
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Melbourne, VIC 3800, Australia; (H.-M.L.); (R.G.); (M.H.)
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Brice AM, Watts E, Hirst B, Jans DA, Ito N, Moseley GW. Implication of the nuclear trafficking of rabies virus P3 protein in viral pathogenicity. Traffic 2021; 22:482-489. [PMID: 34622522 DOI: 10.1111/tra.12821] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/27/2021] [Accepted: 10/04/2021] [Indexed: 11/27/2022]
Abstract
Although the majority of viruses of the family Mononegvirales replicate exclusively in the host cell cytoplasm, many of these viruses encode proteins that traffic between the nucleus and cytoplasm, which is believed to enable accessory functions in modulating the biology of the infected host cell. Among these, the P3 protein of rabies virus localizes to the nucleus through the activity of several specific nuclear localization and nuclear export signals. The major defined functions of P3 are in evasion of interferon (IFN)-mediated antiviral responses, including through inhibition of DNA-binding by IFN-activated STAT1. P3 also localizes to nucleoli and promyelocytic leukemia (PML) nuclear bodies, and interacts with nucleolin and PML protein, indicative of several intranuclear roles. The relationship of P3 nuclear localization with pathogenicity, however, is unresolved. We report that nucleocytoplasmic localization of P3 proteins from a pathogenic RABV strain, Nishigahara (Ni) and a non-pathogenic Ni-derived strain, Ni-CE, differs significantly, with nuclear accumulation defective for Ni-CE-P3. Molecular mapping indicates that altered localization derives from a coordinated effect, including two residue substitutions that independently disable nuclear localization and augment nuclear export signals, collectively promoting nuclear exclusion. Intriguingly, this appears to relate to effects on protein conformation or regulatory mechanisms, rather than direct modification of defined trafficking signal sequences. These data provide new insights into the role of regulated nuclear trafficking of a viral protein in the pathogenicity of a virus that replicates in the cytoplasm.
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Affiliation(s)
- Aaron M Brice
- Viral Pathogenesis Laboratory, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Ericka Watts
- Viral Pathogenesis Laboratory, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Bevan Hirst
- Viral Pathogenesis Laboratory, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Naoto Ito
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, and United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Gregory W Moseley
- Viral Pathogenesis Laboratory, Department of Microbiology, Monash University, Clayton, Victoria, Australia
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Abstract
Although transport into the nucleus mediated by the importin (IMP) α/β1-heterodimer is central to viral infection, small molecule inhibitors of IMPα/β1-dependent nuclear import have only been described and shown to have antiviral activity in the last decade. Their robust antiviral activity is due to the strong reliance of many different viruses, including RNA viruses such as human immunodeficiency virus-1 (HIV-1), dengue (DENV), and Zika (ZIKV), on the IMPα/β1-virus interface. High-throughput compound screens have identified many agents that specifically target this interface. Of these, agents targeting IMPα/β1 directly include the FDA-approved macrocyclic lactone ivermectin, which has documented broad-spectrum activity against a whole range of viruses, including HIV-1, DENV1-4, ZIKV, West Nile virus (WNV), Venezuelan equine encephalitis virus, chikungunya, and most recently, SARS-CoV-2 (COVID-19). Ivermectin has thus far been tested in Phase III human clinical trials for DENV, while there are currently close to 80 trials in progress worldwide for SARS-CoV-2; preliminary results for randomised clinical trials (RCTs) as well as observational/retrospective studies are consistent with ivermectin affording clinical benefit. Agents that target the viral component of the IMPα/β1-virus interface include N-(4-hydroxyphenyl) retinamide (4-HPR), which specifically targets DENV/ZIKV/WNV non-structural protein 5 (NS5). 4-HPR has been shown to be a potent inhibitor of infection by DENV1-4, including in an antibody-dependent enhanced animal challenge model, as well as ZIKV, with Phase II clinical challenge trials planned. The results from rigorous RCTs will help determine the therapeutic potential of the IMPα/β1-virus interface as a target for antiviral development.
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Affiliation(s)
- Alexander J. Martin
- Nuclear Signaling Lab., Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia
| | - David A. Jans
- Nuclear Signaling Lab., Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia
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12
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Jagga B, Edwards M, Pagin M, Wagstaff KM, Aragão D, Roman N, Nanson JD, Raidal SR, Dominado N, Stewart M, Jans DA, Hime GR, Nicolis SK, Basler CF, Forwood JK. Structural basis for nuclear import selectivity of pioneer transcription factor SOX2. Nat Commun 2021; 12:28. [PMID: 33397924 PMCID: PMC7782513 DOI: 10.1038/s41467-020-20194-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/26/2020] [Indexed: 12/17/2022] Open
Abstract
SOX (SRY-related HMG-box) transcription factors perform critical functions in development and cell differentiation. These roles depend on precise nuclear trafficking, with mutations in the nuclear targeting regions causing developmental diseases and a range of cancers. SOX protein nuclear localization is proposed to be mediated by two nuclear localization signals (NLSs) positioned within the extremities of the DNA-binding HMG-box domain and, although mutations within either cause disease, the mechanistic basis has remained unclear. Unexpectedly, we find here that these two distantly positioned NLSs of SOX2 contribute to a contiguous interface spanning 9 of the 10 ARM domains on the nuclear import adapter IMPα3. We identify key binding determinants and show this interface is critical for neural stem cell maintenance and for Drosophila development. Moreover, we identify a structural basis for the preference of SOX2 binding to IMPα3. In addition to defining the structural basis for SOX protein localization, these results provide a platform for understanding how mutations and post-translational modifications within these regions may modulate nuclear localization and result in clinical disease, and also how other proteins containing multiple NLSs may bind IMPα through an extended recognition interface. The SOX2 pioneer transcription factor performs critical roles in pluripotency and self-renewal of embryonic stem cells. Here the authors show that SOX2’s two nuclear localization signal sequences form a contiguous binding interface on the nuclear import receptor importin-α3, and provide a structural basis for the preference of SOX2 binding to IMPα3.
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Affiliation(s)
- Bikshapathi Jagga
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW, 2678, Australia
| | - Megan Edwards
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, 30303, USA
| | - Miriam Pagin
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, piazza della Scienza 2, 20126, Milano, Italy
| | - Kylie M Wagstaff
- Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - David Aragão
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE, UK
| | - Noelia Roman
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW, 2678, Australia
| | - Jeffrey D Nanson
- School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research Centre, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Shane R Raidal
- School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, 2678, Australia
| | - Nicole Dominado
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Murray Stewart
- MRC Laboratory of Molecular Biology, Francis Crick Ave., Cambridge Biomedical Campus, Cambridge, CB2 0QH, UK
| | - David A Jans
- Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Gary R Hime
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Silvia K Nicolis
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, piazza della Scienza 2, 20126, Milano, Italy
| | - Christopher F Basler
- Center for Microbial Pathogenesis, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, 30303, USA
| | - Jade K Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW, 2678, Australia.
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13
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Shechter S, Thomas DR, Jans DA. Application of In Silico and HTS Approaches to Identify Nuclear Import Inhibitors for Venezuelan Equine Encephalitis Virus Capsid Protein: A Case Study. Front Chem 2020; 8:573121. [PMID: 33505952 PMCID: PMC7832173 DOI: 10.3389/fchem.2020.573121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/12/2020] [Indexed: 01/16/2023] Open
Abstract
The development of new drugs is costly and time-consuming, with estimates of over $US1 billion and 15 years for a product to reach the market. As understanding of the molecular basis of disease improves, various approaches have been used to target specific molecular interactions in the search for effective drugs. These include high-throughput screening (HTS) for novel drug identification and computer-aided drug design (CADD) to assess the properties of putative drugs before experimental work begins. We have applied conventional HTS and CADD approaches to the problem of identifying antiviral compounds to limit infection by Venezuelan equine encephalitis virus (VEEV). Nuclear targeting of the VEEV capsid (CP) protein through interaction with the host nuclear import machinery has been shown to be essential for viral pathogenicity, with viruses incapable of this interaction being greatly attenuated. Our previous conventional HTS and in silico structure-based drug design (SBDD) screens were successful in identifying novel inhibitors of CP interaction with the host nuclear import machinery, thus providing a unique opportunity to assess the relative value of the two screening approaches directly. This focused review compares and contrasts the two screening approaches, together with the properties of the inhibitors identified, as a case study for parallel use of the two approaches to identify antivirals. The utility of SBDD screens, especially when used in parallel with traditional HTS, in identifying agents of interest to target the host-pathogen interface is highlighted.
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Affiliation(s)
- Sharon Shechter
- Shechter Computational Solutions, Andover, MA, United States.,Department of Chemistry, College of Sciences, University of Massachusetts Lowell, Lowell, MA, United States
| | - David R Thomas
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Biomedical Discovery Institute, Monash University, Monash, VIC, Australia
| | - David A Jans
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Biomedical Discovery Institute, Monash University, Monash, VIC, Australia
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14
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Fatima S, Wagstaff KM, Lim SM, Polo JM, Young JC, Jans DA. The nuclear transporter importin 13 is critical for cell survival during embryonic stem cell differentiation. Biochem Biophys Res Commun 2020; 534:141-148. [PMID: 33333437 DOI: 10.1016/j.bbrc.2020.11.099] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 11/23/2020] [Indexed: 12/12/2022]
Abstract
Nuclear transporter Importin (Imp, Ipo) 13 is known to transport various mammalian cargoes into/out of the nucleus, but its role in directing cell-fate is unclear. Here we examine the role of Imp13 in the maintenance of pluripotency and differentiation of embryonic stem cells (ESCs) for the first time, using an embryonic body (EB)-based model. When induced to differentiate, Ipo13-/- ESCs displayed slow proliferation, reduced EB size, and lower expression of the proliferation marker KI67, concomitant with an increase in the number of TUNEL+ nuclei compared to wildtype ESCs. At days 5 and 10 of differentiation, Ipo13-/- EBs also showed enhanced loss of the pluripotency transcript OCT3/4, and barely detectable clusters of OCT3/4 positive cells. Day 5 Ipo13-/- EBs further exhibited reduced levels of the mesodermal markers Brachyury and Mixl1, correlating with reduced numbers of haemoglobinised cells generated. Our findings suggest that Imp13 is critical to ESC survival as well as early post-gastrulation differentiation.
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Affiliation(s)
- Shadma Fatima
- Nuclear Signalling Lab., Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Kylie M Wagstaff
- Nuclear Signalling Lab., Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - Sue Mei Lim
- Australian Regenerative Medicine Institute, Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Jose M Polo
- Australian Regenerative Medicine Institute, Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Julia C Young
- Department of Anatomy and Developmental Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia
| | - David A Jans
- Nuclear Signalling Lab., Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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15
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Jans DA, Wagstaff KM. The broad spectrum host-directed agent ivermectin as an antiviral for SARS-CoV-2 ? Biochem Biophys Res Commun 2020; 538:163-172. [PMID: 33341233 PMCID: PMC7577703 DOI: 10.1016/j.bbrc.2020.10.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [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: 10/15/2020] [Accepted: 10/18/2020] [Indexed: 12/16/2022]
Abstract
FDA approved for parasitic indications, the small molecule ivermectin has been the focus of growing attention in the last 8 years due to its potential as an antiviral. We first identified ivermectin in a high throughput compound library screen as an agent potently able to inhibit recognition of the nuclear localizing Human Immunodeficiency Virus-1 (HIV-1) integrase protein by the host importin (IMP) α/β1 heterodimer, and recently demonstrated its ability to bind directly to IMPα to cause conformational changes that prevent its function in nuclear import of key viral as well as host proteins. Cell culture experiments have shown robust antiviral action towards a whole range of viruses, including HIV-1, dengue, Zika and West Nile Virus, Venezuelan equine encephalitis virus, Chikungunya, pseudorabies virus, adenovirus, and SARS-CoV-2 (COVID-19). Close to 70 clinical trials are currently in progress worldwide for SARS-CoV-2. Although few of these studies have been completed, the results that are available, as well as those from observational/retrospective studies, indicate clinical benefit. Here we discuss the case for ivermectin as a host-directed broad-spectrum antiviral agent, including for SARS-CoV-2.
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Affiliation(s)
- David A Jans
- Nuclear Signaling Lab., Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
| | - Kylie M Wagstaff
- Cancer Targeting and Nuclear Therapeutics Lab., Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
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16
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Zhang S, Williamson NA, Duvick L, Lee A, Orr HT, Korlin-Downs A, Yang P, Mok YF, Jans DA, Bogoyevitch MA. The ataxin-1 interactome reveals direct connection with multiple disrupted nuclear transport pathways. Nat Commun 2020; 11:3343. [PMID: 32620905 PMCID: PMC7334205 DOI: 10.1038/s41467-020-17145-0] [Citation(s) in RCA: 12] [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: 08/06/2017] [Accepted: 06/09/2020] [Indexed: 11/21/2022] Open
Abstract
The expanded polyglutamine (polyQ) tract form of ataxin-1 drives disease progression in spinocerebellar ataxia type 1 (SCA1). Although known to form distinctive intranuclear bodies, the cellular pathways and processes that polyQ-ataxin-1 influences remain poorly understood. Here we identify the direct and proximal partners constituting the interactome of ataxin-1[85Q] in Neuro-2a cells, pathways analyses indicating a significant enrichment of essential nuclear transporters, pointing to disruptions in nuclear transport processes in the presence of elevated levels of ataxin-1. Our direct assessments of nuclear transporters and their cargoes confirm these observations, revealing disrupted trafficking often with relocalisation of transporters and/or cargoes to ataxin-1[85Q] nuclear bodies. Analogous changes in importin-β1, nucleoporin 98 and nucleoporin 62 nuclear rim staining are observed in Purkinje cells of ATXN1[82Q] mice. The results highlight a disruption of multiple essential nuclear protein trafficking pathways by polyQ-ataxin-1, a key contribution to furthering understanding of pathogenic mechanisms initiated by polyQ tract proteins.
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Affiliation(s)
- Sunyuan Zhang
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Nicholas A Williamson
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Lisa Duvick
- Institute of Translational Neuroscience, and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Alexander Lee
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Harry T Orr
- Institute of Translational Neuroscience, and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Austin Korlin-Downs
- Institute of Translational Neuroscience, and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Praseuth Yang
- Institute of Translational Neuroscience, and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Yee-Foong Mok
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - David A Jans
- Nuclear Signalling Lab., Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia.
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, 3010, Australia
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17
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Major AT, Hogarth CA, Young JC, Kurihara Y, Jans DA, Loveland KL. Dynamic paraspeckle component localisation during spermatogenesis. Reproduction 2020; 158:267-280. [PMID: 31299635 DOI: 10.1530/rep-19-0139] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 07/12/2019] [Indexed: 11/08/2022]
Abstract
Expression profiles and subcellular localisations of core Drosophila behaviour/human splicing (DBHS) proteins (PSPC1, SFPQ and NONO) and NEAT1, a long noncoding RNA (lncRNA), are investigated in developing and adult mouse testes. Core DBHS proteins are markers for the distinct subnuclear domain termed paraspeckles, while a long NEAT1 isoform scaffold facilitates paraspeckle nucleation. Paraspeckles contain many proteins (>40) and are broadly involved in RNA metabolism, including transcriptional regulation by protein sequestration, nuclear retention of A-to-I edited RNA transcripts to regulate translation and promoting survival during cellular stress. Immunohistochemistry reveals cell-specific profiles for core DBHS paraspeckle protein expression, indicating their functional diversity. PSPC1 is an androgen receptor co-activator, and it is detected in differentiating Sertoli cell nuclei from day 15 onwards, as they develop androgen responsiveness. PSPC1 is nuclear in the most mature male germ cell type present at each age, from foetal to adult life. In adult mouse testes, PSPC1 and SFPQ are present in Sertoli cells, spermatocytes and round spermatids, while the NEAT1 lncRNA appears in the punctate nuclear foci delineating paraspeckles only within Leydig cells. Identification of NEAT1 in the cytoplasm of spermatogonia and spermatocytes must reflect non-paraspeckle-related functions. NONO was absent from germ cells but nuclear in Sertoli cells. Reciprocal nuclear profiles of PSPC1 and γ-H2AX in spermatogenic cells suggest that each performs developmentally regulated roles in stress responses. These findings demonstrate paraspeckles and paraspeckle-related proteins contribute to diverse functions during testis development and spermatogenesis.
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Affiliation(s)
- Andrew T Major
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,The ARC Centre of Excellence in Biotechnology and Development, Melbourne, Australia
| | - Cathryn A Hogarth
- The ARC Centre of Excellence in Biotechnology and Development, Melbourne, Australia.,Department of Pharmacy and Biomedical Sciences, La Trobe University, Albury-Wodonga, Australia
| | - Julia C Young
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,The ARC Centre of Excellence in Biotechnology and Development, Melbourne, Australia
| | - Yasuyuki Kurihara
- Faculty of Engineering Science, Yokohama National University, Yokohama, Japan
| | - David A Jans
- The ARC Centre of Excellence in Biotechnology and Development, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
| | - Kate L Loveland
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Australia.,The ARC Centre of Excellence in Biotechnology and Development, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia.,Centre for Reproductive Health, Hudson Institute of Medical Research, Melbourne, Australia.,School of Clinical Sciences, Monash University, Melbourne, Australia
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18
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Caly L, Druce JD, Catton MG, Jans DA, Wagstaff KM. The FDA-approved drug ivermectin inhibits the replication of SARS-CoV-2 in vitro. Antiviral Res 2020; 178:104787. [PMID: 32251768 PMCID: PMC7129059 DOI: 10.1016/j.antiviral.2020.104787] [Citation(s) in RCA: 1225] [Impact Index Per Article: 306.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 03/27/2020] [Accepted: 03/29/2020] [Indexed: 12/12/2022]
Abstract
Although several clinical trials are now underway to test possible therapies, the worldwide response to the COVID-19 outbreak has been largely limited to monitoring/containment. We report here that Ivermectin, an FDA-approved anti-parasitic previously shown to have broad-spectrum anti-viral activity in vitro, is an inhibitor of the causative virus (SARS-CoV-2), with a single addition to Vero-hSLAM cells 2 h post infection with SARS-CoV-2 able to effect ~5000-fold reduction in viral RNA at 48 h. Ivermectin therefore warrants further investigation for possible benefits in humans.
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Affiliation(s)
- Leon Caly
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital, At the Peter Doherty Institute for Infection and Immunity, Victoria, 3000, Australia
| | - Julian D Druce
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital, At the Peter Doherty Institute for Infection and Immunity, Victoria, 3000, Australia
| | - Mike G Catton
- Victorian Infectious Diseases Reference Laboratory, Royal Melbourne Hospital, At the Peter Doherty Institute for Infection and Immunity, Victoria, 3000, Australia
| | - David A Jans
- Biomedicine Discovery Institute, Monash University, Clayton, Vic, 3800, Australia
| | - Kylie M Wagstaff
- Biomedicine Discovery Institute, Monash University, Clayton, Vic, 3800, Australia.
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19
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Abstract
Respiratory syncytial virus (RSV) is one of the leading causes of viral respiratory tract infection in infants, the elderly, and the immunocompromised worldwide, causing more deaths each year than influenza. Years of research into RSV since its discovery over 60 yr ago have elucidated detailed mechanisms of the host-pathogen interface. RSV infection elicits widespread transcriptomic and proteomic changes, which both mediate the host innate and adaptive immune responses to infection, and reflect RSV's ability to circumvent the host stress responses, including stress granule formation, endoplasmic reticulum stress, oxidative stress, and programmed cell death. The combination of these events can severely impact on human lungs, resulting in airway remodeling and pathophysiology. The RSV membrane envelope glycoproteins (fusion F and attachment G), matrix (M) and nonstructural (NS) 1 and 2 proteins play key roles in modulating host cell functions to promote the infectious cycle. This review presents a comprehensive overview of how RSV impacts the host response to infection and how detailed knowledge of the mechanisms thereof can inform the development of new approaches to develop RSV vaccines and therapeutics.
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Affiliation(s)
- MengJie Hu
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Victoria, Australia; and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Victoria, Australia; and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Victoria, Australia; and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
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20
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Yang SNY, Atkinson SC, Wang C, Lee A, Bogoyevitch MA, Borg NA, Jans DA. The broad spectrum antiviral ivermectin targets the host nuclear transport importin α/β1 heterodimer. Antiviral Res 2020; 177:104760. [PMID: 32135219 DOI: 10.1016/j.antiviral.2020.104760] [Citation(s) in RCA: 193] [Impact Index Per Article: 48.3] [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: 12/18/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 12/11/2022]
Abstract
Infection by RNA viruses such as human immunodeficiency virus (HIV)-1, influenza, and dengue virus (DENV) represent a major burden for human health worldwide. Although RNA viruses replicate in the infected host cell cytoplasm, the nucleus is central to key stages of the infectious cycle of HIV-1 and influenza, and an important target of DENV nonstructural protein 5 (NS5) in limiting the host antiviral response. We previously identified the small molecule ivermectin as an inhibitor of HIV-1 integrase nuclear entry, subsequently showing ivermectin could inhibit DENV NS5 nuclear import, as well as limit infection by viruses such as HIV-1 and DENV. We show here that ivermectin's broad spectrum antiviral activity relates to its ability to target the host importin (IMP) α/β1 nuclear transport proteins responsible for nuclear entry of cargoes such as integrase and NS5. We establish for the first time that ivermectin can dissociate the preformed IMPα/β1 heterodimer, as well as prevent its formation, through binding to the IMPα armadillo (ARM) repeat domain to impact IMPα thermal stability and α-helicity. We show that ivermectin inhibits NS5-IMPα interaction in a cell context using quantitative bimolecular fluorescence complementation. Finally, we show for the first time that ivermectin can limit infection by the DENV-related West Nile virus at low (μM) concentrations. Since it is FDA approved for parasitic indications, ivermectin merits closer consideration as a broad spectrum antiviral of interest.
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Affiliation(s)
- Sundy N Y Yang
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia
| | - Sarah C Atkinson
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia
| | - Chunxiao Wang
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia
| | - Alexander Lee
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia
| | - Natalie A Borg
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia
| | - David A Jans
- Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic, 3800, Australia.
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21
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Heaton SM, Atkinson SC, Sweeney MN, Yang SNY, Jans DA, Borg NA. Exportin-1-Dependent Nuclear Export of DEAD-box Helicase DDX3X is Central to its Role in Antiviral Immunity. Cells 2019; 8:E1181. [PMID: 31575075 PMCID: PMC6848931 DOI: 10.3390/cells8101181] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [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: 08/15/2019] [Revised: 09/16/2019] [Accepted: 09/28/2019] [Indexed: 12/14/2022] Open
Abstract
DEAD-box helicase 3, X-linked (DDX3X) regulates the retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-mediated antiviral response, but can also be a host factor contributing to the replication of viruses of significance to human health, such as human immunodeficiency virus type 1 (HIV-1). These roles are mediated in part through its ability to actively shuttle between the nucleus and the cytoplasm to modulate gene expression, although the trafficking mechanisms, and impact thereof on immune signaling and viral infection, are incompletely defined. We confirm that DDX3X nuclear export is mediated by the nuclear transporter exportin-1/CRM1, dependent on an N-terminal, leucine-rich nuclear export signal (NES) and the monomeric guanine nucleotide binding protein Ran in activated GTP-bound form. Transcriptome profiling and ELISA show that exportin-1-dependent export of DDX3X to the cytoplasm strongly impacts IFN-β production and the upregulation of immune genes in response to infection. That this is key to DDX3X's antiviral role was indicated by enhanced infection by human parainfluenza virus-3 (hPIV-3)/elevated virus production when the DDX3X NES was inactivated. Our results highlight a link between nucleocytoplasmic distribution of DDX3X and its role in antiviral immunity, with strong relevance to hPIV-3, as well as other viruses such as HIV-1.
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Affiliation(s)
- Steven M Heaton
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Sarah C Atkinson
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Melissa N Sweeney
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Sundy N Y Yang
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - David A Jans
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Natalie A Borg
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
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22
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Giovannoni F, Ladelfa MF, Monte M, Jans DA, Hemmerich P, García C. Dengue Non-structural Protein 5 Polymerase Complexes With Promyelocytic Leukemia Protein (PML) Isoforms III and IV to Disrupt PML-Nuclear Bodies in Infected Cells. Front Cell Infect Microbiol 2019; 9:284. [PMID: 31456950 PMCID: PMC6701172 DOI: 10.3389/fcimb.2019.00284] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [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: 04/11/2019] [Accepted: 07/24/2019] [Indexed: 12/23/2022] Open
Abstract
Dengue virus (DENV) threatens almost 70% of the world's population, with no therapeutic currently available. The severe, potentially lethal forms of DENV disease (dengue hemorrhagic fever/dengue shock syndrome) are associated with the production of high level of cytokines, elicited as part of the host antiviral response, although the molecular mechanisms have not been fully elucidated. We previously showed that infection by DENV serotype 2 (DENV2) disrupts promyelocytic leukemia (PML) gene product nuclear bodies (PML-NBs) after viral protein translation in infected cells. Apart from playing a key role as the nucleating agent in forming PML-NBs, PML has antiviral activity against various viruses, including DENV. The present study builds on this work, showing for the first time that all four DENV serotypes elicit PML-NB breakdown. Importantly, we show for the first time that of the nuclear localizing proteins of DENV, DENV non-structural protein (NS) 5 polymerase alone is sufficient to elicit PML-NB disassembly, in part through complexing with PML isoforms III and IV, but not other PML isoforms or other PML-NB components. The results raise the possibility that PML-NB disruption by nuclear localized NS5 contributes to DENV's suppression of the host antiviral response.
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Affiliation(s)
- Federico Giovannoni
- Laboratorio de Estrategias Antivirales, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Bioológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María Fatima Ladelfa
- Instituto de Química Bioológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Laboratory of Molecular Oncology, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Martin Monte
- Instituto de Química Bioológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
- Laboratory of Molecular Oncology, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - David A. Jans
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | | | - Cybele García
- Laboratorio de Estrategias Antivirales, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Bioológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
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23
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Hu M, Schulze KE, Ghildyal R, Henstridge DC, Kolanowski JL, New EJ, Hong Y, Hsu AC, Hansbro PM, Wark PA, Bogoyevitch MA, Jans DA. Respiratory syncytial virus co-opts host mitochondrial function to favour infectious virus production. eLife 2019; 8:42448. [PMID: 31246170 PMCID: PMC6598784 DOI: 10.7554/elife.42448] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 06/10/2019] [Indexed: 12/15/2022] Open
Abstract
Although respiratory syncytial virus (RSV) is responsible for more human deaths each year than influenza, its pathogenic mechanisms are poorly understood. Here high-resolution quantitative imaging, bioenergetics measurements and mitochondrial membrane potential- and redox-sensitive dyes are used to define RSV’s impact on host mitochondria for the first time, delineating RSV-induced microtubule/dynein-dependent mitochondrial perinuclear clustering, and translocation towards the microtubule-organizing centre. These changes are concomitant with impaired mitochondrial respiration, loss of mitochondrial membrane potential and increased production of mitochondrial reactive oxygen species (ROS). Strikingly, agents that target microtubule integrity the dynein motor protein, or inhibit mitochondrial ROS production strongly suppresses RSV virus production, including in a mouse model with concomitantly reduced virus-induced lung inflammation. The results establish RSV’s unique ability to co-opt host cell mitochondria to facilitate viral infection, revealing the RSV-mitochondrial interface for the first time as a viable target for therapeutic intervention.
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Affiliation(s)
- MengJie Hu
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia.,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
| | - Keith E Schulze
- Monash Micro Imaging, Monash University, Melbourne, Australia
| | - Reena Ghildyal
- Centre for Research in Therapeutic Solutions, Faculty of Science and Technology, University of Canberra, Canberra, Australia
| | | | | | - Elizabeth J New
- School of Chemistry, The University of Sydney, Sydney, Australia
| | - Yuning Hong
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Alan C Hsu
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Philip M Hansbro
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Peter Ab Wark
- Priority Research Centre for Healthy Lungs, Hunter Medical Research Institute (HMRI) and School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
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24
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Ng IHW, Chan KWK, Tan MJA, Gwee CP, Smith KM, Jeffress SJ, Saw WG, Swarbrick CMD, Watanabe S, Jans DA, Grüber G, Forwood JK, Vasudevan SG. Zika Virus NS5 Forms Supramolecular Nuclear Bodies That Sequester Importin-α and Modulate the Host Immune and Pro-Inflammatory Response in Neuronal Cells. ACS Infect Dis 2019; 5:932-948. [PMID: 30848123 DOI: 10.1021/acsinfecdis.8b00373] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 12/17/2022]
Abstract
The Zika virus (ZIKV) epidemic in the Americas was alarming because of its link with microcephaly in neonates and Guillain-Barré syndrome in adults. The unusual pathologies induced by ZIKV infection and the knowledge that the flaviviral nonstructural protein 5 (NS5), the most conserved protein in the flavivirus proteome, can modulate the host immune response during ZIKV infection prompted us to investigate the subcellular localization of NS5 during ZIKV infection and explore its functional significance. A monopartite nuclear localization signal (NLS) sequence within ZIKV NS5 was predicted by the cNLS Mapper program, and we observed localization of ZIKV NS5 in the nucleus of infected cells by immunostaining with specific antibodies. Strikingly, ZIKV NS5 forms spherical shell-like nuclear bodies that exclude DNA. The putative monopartite NLS 390KRPR393 is necessary to direct FLAG-tagged NS5 to the nucleus as the NS5 390ARPA393 mutant protein accumulates in the cytoplasm. Furthermore, coimmunostaining experiments reveal that NS5 localizes with and sequesters importin-α, but not importin-β, in the observed nuclear bodies during virus infection. Structural and biochemical data demonstrate binding of ZIKV NS5 with importin-α and reveal important binding determinants required for their interaction and formation of complexes that give rise to the supramolecular nuclear bodies. Significantly, we demonstrate a neuronal-specific activation of the host immune response to ZIKV infection and a possible role of ZIKV NS5's nuclear localization toward this activation. This suggests that ZIKV pathogenesis may arise from a tissue-specific host response to ZIKV infection.
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Affiliation(s)
- Ivan H. W. Ng
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Kitti Wing-Ki Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore 117545
| | - Min Jie Alvin Tan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Genome Institute of Singapore, Agency for Science & Technology Research (A*STAR), 60 Biopolis Street, Singapore 138672
| | - Chin Piaw Gwee
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Kate M. Smith
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Sarah J. Jeffress
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Wuan-Geok Saw
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Crystall M. D. Swarbrick
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - Satoru Watanabe
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
| | - David A. Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Jade K. Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales 2650, Australia
| | - Subhash G. Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
- Department of Microbiology and Immunology, National University of Singapore, 5 Science Drive 2, Singapore 117545
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25
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Tano V, Jans DA, Bogoyevitch MA. Oligonucleotide-directed STAT3 alternative splicing switch drives anti-tumorigenic outcomes in MCF10 human breast cancer cells. Biochem Biophys Res Commun 2019; 513:1076-1082. [PMID: 31010684 DOI: 10.1016/j.bbrc.2019.04.054] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/07/2019] [Indexed: 11/27/2022]
Abstract
Signal transducer and activator of transcription 3 (STAT3), a transcription factor responsive to the activation of cytokine receptors, is known for its oncogenic actions. Whilst STAT3α is the predominant spliceform in most tissues, alternative splicing of the STAT3 gene can generate a shorter STAT3β spliceform. Redirecting splicing to enhance STAT3β levels can result in tumor suppression in vivo, and so we evaluated the cellular basis underlying the anti-tumorigenic properties of STAT3β. To investigate the impact of increased STAT3β levels in cancer cells, we implemented a Morpholino-based antisense oligonucleotide strategy to modulate STAT3 spliceform expression in the MCF10CA1h cancer cells of the MCF10 series of human breast cancer cells. We employed nonsense-mediated decay (NMD) oligonucleotides and STAT3α-to-β expression switching (SWI) oligonucleotides to successfully induce STAT3 knockdown and redirect alternative splicing to increase STAT3β levels in MCF10CA1h cells, respectively. Importantly, assessment of the impacts of STAT3 splicing modulation on tumor cell biology showed that the SWI treatment significantly reduced MCF10CA1h cell growth, viability, and migration, whereas NMD treatment was without significant impact, although neither NMD nor SWI oligonucleotides significantly inhibited MCF10CA1h cell invasion through a semi-solid matrix. In conclusion, our data demonstrate that reduced breast cancer cell growth, viability and migration, but not invasion, follow the redirection of STAT3α-to-β expression switching to favour STAT3β expression.
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Affiliation(s)
- Vincent Tano
- Department of Biochemistry and Molecular Biology, Medical Building, University of Melbourne, Parkville, VIC, 3010, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Building 77, Monash University, Clayton, VIC, 3168, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, Medical Building, University of Melbourne, Parkville, VIC, 3010, Australia.
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26
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Yang SNY, Atkinson SC, Fraser JE, Wang C, Maher B, Roman N, Forwood JK, Wagstaff KM, Borg NA, Jans DA. Novel Flavivirus Antiviral That Targets the Host Nuclear Transport Importin α/β1 Heterodimer. Cells 2019; 8:cells8030281. [PMID: 30909636 PMCID: PMC6468590 DOI: 10.3390/cells8030281] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/19/2019] [Accepted: 03/20/2019] [Indexed: 12/20/2022] Open
Abstract
Dengue virus (DENV) threatens almost 70% of the world’s population, with no effective vaccine or therapeutic currently available. A key contributor to infection is nuclear localisation in the infected cell of DENV nonstructural protein 5 (NS5) through the action of the host importin (IMP) α/β1 proteins. Here, we used a range of microscopic, virological and biochemical/biophysical approaches to show for the first time that the small molecule GW5074 has anti-DENV action through its novel ability to inhibit NS5–IMPα/β1 interaction in vitro as well as NS5 nuclear localisation in infected cells. Strikingly, GW5074 not only inhibits IMPα binding to IMPβ1, but can dissociate preformed IMPα/β1 heterodimer, through targeting the IMPα armadillo (ARM) repeat domain to impact IMPα thermal stability and α-helicity, as shown using analytical ultracentrifugation, thermostability analysis and circular dichroism measurements. Importantly, GW5074 has strong antiviral activity at low µM concentrations against not only DENV-2, but also zika virus and West Nile virus. This work highlights DENV NS5 nuclear targeting as a viable target for anti-flaviviral therapeutics.
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Affiliation(s)
- Sundy N Y Yang
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Sarah C Atkinson
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Johanna E Fraser
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Chunxiao Wang
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Belinda Maher
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Noelia Roman
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
| | - Jade K Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia.
| | - Kylie M Wagstaff
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - Natalie A Borg
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
| | - David A Jans
- Nuclear Signaling Laboratory, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
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27
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Abstract
Central to eukaryotic cell function, transport into and out of the nucleus is largely mediated by members of the Importin (IMP) superfamily of transporters of α- and β-types. The first inhibitor of nuclear transport, leptomycin B (LMB), was shown to be a specific inhibitor of the IMPβ homologue Exportin 1 (EXP1) almost 20 years ago, but it has only been in the last five or so years that new inhibitors of nuclear export as well as import have been identified and characterised. Of utility in biological research, these inhibitors include those that target-specific EXPs/IMPs, with accompanying toxicity profiles, as well as agents that specifically target particular nuclear import cargoes. Both types of inhibitors have begun to be tested in preclinical/clinical studies, with particular focus on limiting various types of cancer or treating viral infection, and the most advanced agent targeting EXP1 (Selinexor) has progressed successfully through >40 clinical trials for a range of high-grade cancers and is approaching FDA approval for a number of indications. Selectively inhibiting the nucleocytoplasmic trafficking of specific proteins of interest remains a challenge, but progress in the area of the host-pathogen interface holds promise for the future.
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Affiliation(s)
- David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
| | - Alexander J Martin
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia
| | - Kylie M Wagstaff
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Australia
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28
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DeBono A, Thomas DR, Lundberg L, Pinkham C, Cao Y, Graham JD, Clarke CL, Wagstaff KM, Shechter S, Kehn-Hall K, Jans DA. Novel RU486 (mifepristone) analogues with increased activity against Venezuelan Equine Encephalitis Virus but reduced progesterone receptor antagonistic activity. Sci Rep 2019; 9:2634. [PMID: 30796232 PMCID: PMC6385310 DOI: 10.1038/s41598-019-38671-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [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: 05/25/2018] [Accepted: 12/27/2018] [Indexed: 12/21/2022] Open
Abstract
There are currently no therapeutics to treat infection with the alphavirus Venezuelan equine encephalitis virus (VEEV), which causes flu-like symptoms leading to neurological symptoms in up to 14% of cases. Large outbreaks of VEEV can result in 10,000 s of human cases and mass equine death. We previously showed that mifepristone (RU486) has anti-VEEV activity (EC50 = 20 μM) and only limited cytotoxicity (CC50 > 100 μM), but a limitation in its use is its abortifacient activity resulting from its ability to antagonize the progesterone receptor (PR). Here we generate a suite of new mifepristone analogues with enhanced antiviral properties, succeeding in achieving >11-fold improvement in anti-VEEV activity with no detectable increase in toxicity. Importantly, we were able to derive a lead compound with an EC50 of 7.2 µM and no detectable PR antagonism activity. Finally, based on our SAR analysis we propose avenues for the further development of these analogues as safe and effective anti-VEEV agents.
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Affiliation(s)
- Aaron DeBono
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - David R Thomas
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology School of Biomedical Sciences, Monash University, Melbourne, Australia
| | - Lindsay Lundberg
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Chelsea Pinkham
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - Ying Cao
- Centre for Cancer Research, The Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - J Dinny Graham
- Centre for Cancer Research, The Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Christine L Clarke
- Centre for Cancer Research, The Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Kylie M Wagstaff
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology School of Biomedical Sciences, Monash University, Melbourne, Australia
| | | | - Kylene Kehn-Hall
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, VA, USA
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology School of Biomedical Sciences, Monash University, Melbourne, Australia.
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29
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Affiliation(s)
- David A. Jans
- Department of Biochemistry and Molecular Biology, Nuclear Signalling Laboratory, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
- *Correspondence: David A. Jans
| | - Alexander S. Sobolev
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Biology, M. V. Lomonosov Moscow State University, Moscow, Russia
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30
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Shechter S, Thomas DR, Lundberg L, Pinkham C, Lin SC, Wagstaff KM, Debono A, Kehn-Hall K, Jans DA. Author Correction: Novel inhibitors targeting Venezuelan equine encephalitis virus capsid protein identified using In Silico Structure-Based-Drug-Design. Sci Rep 2018; 8:13487. [PMID: 30177745 PMCID: PMC6120891 DOI: 10.1038/s41598-018-31644-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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31
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Wagstaff KM, Headey S, Telwatte S, Tyssen D, Hearps AC, Thomas DR, Tachedjian G, Jans DA. Molecular dissection of an inhibitor targeting the HIV integrase dependent preintegration complex nuclear import. Cell Microbiol 2018; 21:e12953. [PMID: 30216959 PMCID: PMC6585680 DOI: 10.1111/cmi.12953] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 08/26/2018] [Accepted: 08/29/2018] [Indexed: 12/14/2022]
Abstract
Human immunodeficiency virus (HIV) continues to be a major contributor to morbidity and mortality worldwide, particularly in developing nations where high cost and logistical issues severely limit the use of current HIV therapeutics. This, combined HIV's high propensity to develop resistance, means that new antiviral agents against novel targets are still urgently required. We previously identified novel anti-HIV agents directed against the nuclear import of the HIV integrase (IN) protein, which plays critical roles in the HIV lifecycle inside the cell nucleus, as well as in transporting the HIV preintegration complex (PIC) into the nucleus. Here we investigate the structure activity relationship of a series of these compounds for the first time, including a newly identified anti-IN compound, budesonide, showing that the extent of binding to the IN core domain correlates directly with the ability of the compound to inhibit IN nuclear transport in a permeabilised cell system. Importantly, compounds that inhibited the nuclear transport of IN were found to significantly decrease HIV viral replication, even in a dividing cell system. Significantly, budesonide or its analogue flunisolide, were able to effect a significant reduction in the presence of specific nuclear forms of the HIV DNA (2-LTR circles), suggesting that the inhibitors work though blocking IN, and potentially PIC, nuclear import. The work presented here represents a platform for further development of these specific inhibitors of HIV replication with therapeutic and prophylactic potential.
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Affiliation(s)
- Kylie M Wagstaff
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Stephen Headey
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Parkville, Australia
| | | | - David Tyssen
- Life Science Division, Burnet Institute, Melbourne, Australia
| | - Anna C Hearps
- Life Science Division, Burnet Institute, Melbourne, Australia.,Department of Infectious Diseases, Melbourne University, Melbourne, Australia
| | - David R Thomas
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | | | - David A Jans
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
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32
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Lopez-Denman AJ, Russo A, Wagstaff KM, White PA, Jans DA, Mackenzie JM. Nucleocytoplasmic shuttling of the West Nile virus RNA-dependent RNA polymerase NS5 is critical to infection. Cell Microbiol 2018; 20:e12848. [PMID: 29582535 DOI: 10.1111/cmi.12848] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [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: 08/21/2017] [Revised: 03/08/2018] [Accepted: 03/16/2018] [Indexed: 01/05/2023]
Abstract
West Nile virus (WNV) is a single-stranded, positive sense RNA virus of the family Flaviviridae and is a significant pathogen of global medical importance. Flavivirus replication is known to be exclusively cytoplasmic, but we show here for the first time that access to the nucleus of the WNV strain Kunjin (WNVKUN ) RNA-dependent RNA polymerase (protein NS5) is central to WNVKUN virus production. We show that treatment of cells with the specific nuclear export inhibitor leptomycin B (LMB) results in increased NS5 nuclear accumulation in WNVKUN -infected cells and NS5-transfected cells, indicative of nucleocytoplasmic shuttling under normal conditions. We used site-directed mutagenesis to identify the nuclear localisation sequence (NLS) responsible for WNVKUN NS5 nuclear targeting, observing that mutation of this NLS resulted in exclusively cytoplasmic accumulation of NS5 even in the presence of leptomycin B. Introduction of NS5 NLS mutations into FLSDX, an infectious clone of WNVKUN , resulted in lethality, suggesting that the ability of NS5 to traffic into the nucleus in integral to WNVKUN replication. This study thus shows for the first time that NLS-dependent trafficking into the nucleus during infection of WNVKUN NS5 is critical for viral replication. Excitingly, specific inhibitors of NS5 nuclear import reduce WNVKUN virus production, proving the principle that inhibition of WNVKUN NS5 nuclear import is a viable therapeutic avenue for antiviral drug development in the future.
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Affiliation(s)
- Adam J Lopez-Denman
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia.,Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Victoria, Australia
| | - Alice Russo
- Faculty of Science, Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - Kylie M Wagstaff
- Department of Biochemistry, Monash University, Melbourne, Victoria, Australia
| | - Peter A White
- Faculty of Science, Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, New South Wales, Australia
| | - David A Jans
- Department of Biochemistry, Monash University, Melbourne, Victoria, Australia
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Victoria, Australia
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33
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Dang LT, Tondl M, Chiu MHH, Revote J, Paten B, Tano V, Tokolyi A, Besse F, Quaife-Ryan G, Cumming H, Drvodelic MJ, Eichenlaub MP, Hallab JC, Stolper JS, Rossello FJ, Bogoyevitch MA, Jans DA, Nim HT, Porrello ER, Hudson JE, Ramialison M. TrawlerWeb: an online de novo motif discovery tool for next-generation sequencing datasets. BMC Genomics 2018; 19:238. [PMID: 29621972 PMCID: PMC5887194 DOI: 10.1186/s12864-018-4630-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 01/30/2018] [Accepted: 03/27/2018] [Indexed: 12/14/2022] Open
Abstract
Background A strong focus of the post-genomic era is mining of the non-coding regulatory genome in order to unravel the function of regulatory elements that coordinate gene expression (Nat 489:57–74, 2012; Nat 507:462–70, 2014; Nat 507:455–61, 2014; Nat 518:317–30, 2015). Whole-genome approaches based on next-generation sequencing (NGS) have provided insight into the genomic location of regulatory elements throughout different cell types, organs and organisms. These technologies are now widespread and commonly used in laboratories from various fields of research. This highlights the need for fast and user-friendly software tools dedicated to extracting cis-regulatory information contained in these regulatory regions; for instance transcription factor binding site (TFBS) composition. Ideally, such tools should not require prior programming knowledge to ensure they are accessible for all users. Results We present TrawlerWeb, a web-based version of the Trawler_standalone tool (Nat Methods 4:563–5, 2007; Nat Protoc 5:323–34, 2010), to allow for the identification of enriched motifs in DNA sequences obtained from next-generation sequencing experiments in order to predict their TFBS composition. TrawlerWeb is designed for online queries with standard options common to web-based motif discovery tools. In addition, TrawlerWeb provides three unique new features: 1) TrawlerWeb allows the input of BED files directly generated from NGS experiments, 2) it automatically generates an input-matched biologically relevant background, and 3) it displays resulting conservation scores for each instance of the motif found in the input sequences, which assists the researcher in prioritising the motifs to validate experimentally. Finally, to date, this web-based version of Trawler_standalone remains the fastest online de novo motif discovery tool compared to other popular web-based software, while generating predictions with high accuracy. Conclusions TrawlerWeb provides users with a fast, simple and easy-to-use web interface for de novo motif discovery. This will assist in rapidly analysing NGS datasets that are now being routinely generated. TrawlerWeb is freely available and accessible at: http://trawler.erc.monash.edu.au. Electronic supplementary material The online version of this article (10.1186/s12864-018-4630-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Louis T Dang
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Markus Tondl
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Man Ho H Chiu
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Jerico Revote
- eResearch, Monash University, Clayton, VIC, Australia
| | - Benedict Paten
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, CA, USA
| | - Vincent Tano
- Department of Biochemistry and Molecular Biology, Bio21 Institute and Cell Signalling Research Laboratories, The University of Melbourne, Melbourne, VIC, Australia
| | - Alex Tokolyi
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Florence Besse
- CNRS, Inserm, Institute of Biology Valrose, Université Côte d'Azur, Parc Valrose, Nice, France
| | - Greg Quaife-Ryan
- School of Biomedical Sciences, The University of Queensland, QLD, Brisbane, Australia
| | - Helen Cumming
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Monash University, Clayton, VIC, Australia
| | - Mark J Drvodelic
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Michael P Eichenlaub
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Jeannette C Hallab
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Julian S Stolper
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Fernando J Rossello
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia
| | - Marie A Bogoyevitch
- Department of Biochemistry and Molecular Biology, Bio21 Institute and Cell Signalling Research Laboratories, The University of Melbourne, Melbourne, VIC, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
| | - Hieu T Nim
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia.,Faculty of Information Technology, Monash University, Clayton, VIC, Australia
| | - Enzo R Porrello
- Murdoch Children's Research Institute, The Royal Children's Hospital, Parkville, VIC, Australia.,Department of Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - James E Hudson
- School of Biomedical Sciences, The University of Queensland, QLD, Brisbane, Australia
| | - Mirana Ramialison
- Australian Regenerative Medicine Institute, Systems Biology Institute Australia, Monash University, Clayton, VIC, Australia.
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Atkinson SC, Audsley MD, Lieu KG, Marsh GA, Thomas DR, Heaton SM, Paxman JJ, Wagstaff KM, Buckle AM, Moseley GW, Jans DA, Borg NA. Recognition by host nuclear transport proteins drives disorder-to-order transition in Hendra virus V. Sci Rep 2018; 8:358. [PMID: 29321677 PMCID: PMC5762688 DOI: 10.1038/s41598-017-18742-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [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: 09/15/2017] [Accepted: 12/15/2017] [Indexed: 01/04/2023] Open
Abstract
Hendra virus (HeV) is a paramyxovirus that causes lethal disease in humans, for which no vaccine or antiviral agent is available. HeV V protein is central to pathogenesis through its ability to interact with cytoplasmic host proteins, playing key antiviral roles. Here we use immunoprecipitation, siRNA knockdown and confocal laser scanning microscopy to show that HeV V shuttles to and from the nucleus through specific host nuclear transporters. Spectroscopic and small angle X-ray scattering studies reveal HeV V undergoes a disorder-to-order transition upon binding to either importin α/β1 or exportin-1/Ran-GTP, dependent on the V N-terminus. Importantly, we show that specific inhibitors of nuclear transport prevent interaction with host transporters, and reduce HeV infection. These findings emphasize the critical role of host-virus interactions in HeV infection, and potential use of compounds targeting nuclear transport, such as the FDA-approved agent ivermectin, as anti-HeV agents.
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Affiliation(s)
- Sarah C Atkinson
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Michelle D Audsley
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Kim G Lieu
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Glenn A Marsh
- CSIRO Livestock Industries, Australian Animal Health Laboratory, Victoria, Australia
| | - David R Thomas
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Steven M Heaton
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Jason J Paxman
- La Trobe Institute for Molecular Sciences and Department of Biochemistry and Genetics, La Trobe University, Melbourne, Victoria, Australia
| | - Kylie M Wagstaff
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ashley M Buckle
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Gregory W Moseley
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - David A Jans
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
| | - Natalie A Borg
- Infection & Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
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Jans DA, Martin AJ. Nucleocytoplasmic Trafficking of Dengue Non-structural Protein 5 as a Target for Antivirals. Advances in Experimental Medicine and Biology 2018; 1062:199-213. [DOI: 10.1007/978-981-10-8727-1_15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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36
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Wang C, Yang SNY, Smith K, Forwood JK, Jans DA. Nuclear import inhibitor N-(4-hydroxyphenyl) retinamide targets Zika virus (ZIKV) nonstructural protein 5 to inhibit ZIKV infection. Biochem Biophys Res Commun 2017; 493:1555-1559. [PMID: 28988109 DOI: 10.1016/j.bbrc.2017.10.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 10/03/2017] [Indexed: 12/31/2022]
Abstract
In the absence of approved therapeutics, Zika virus (ZIKV)'s recent prolific outbreaks in the Americas, together with impacts on unborn fetuses of infected mothers, make it a pressing human health concern worldwide. Although a key player in viral replication in the infected host cell cytoplasm, ZIKV non-structural protein 5 (NS5) appears to contribute integrally to pathogenesis by localising in the host cell nucleus, in similar fashion to NS5 from Dengue virus (DENV). We show here for the first time that ZIKV NS5 is recognized with high nanomolar affinity by the host cell importin α/β1 heterodimer, and that this interaction can be blocked by the novel DENV NS5 targeting inhibitor N-(4-hydroxyphenyl) retinamide (4-HPR). Importantly, we show that 4-HPR has potent anti-ZIKV activity at low μM concentrations. With an established safety profile for human use, 4-HPR represents an exciting possibility as an anti-ZIKV agent.
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Affiliation(s)
- Chunxiao Wang
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia
| | - Sundy N Y Yang
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia
| | - Kate Smith
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia
| | - Jade K Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Vic. 3800, Australia.
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McLinton EC, Wagstaff KM, Lee A, Moseley GW, Marsh GA, Wang LF, Jans DA, Lieu KG, Netter HJ. Nuclear localization and secretion competence are conserved among henipavirus matrix proteins. J Gen Virol 2017; 98:563-576. [PMID: 28056216 DOI: 10.1099/jgv.0.000703] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Viruses of the genus Henipavirus of the family Paramyxoviridae are zoonotic pathogens, which have emerged in Southeast Asia, Australia and Africa. Nipah virus (NiV) and Hendra virus are highly virulent pathogens transmitted from bats to animals and humans, while the henipavirus Cedar virus seems to be non-pathogenic in infection studies. The full replication cycle of the Paramyxoviridae occurs in the host cell's cytoplasm, where viral assembly is orchestrated by the matrix (M) protein. Unexpectedly, the NiV-M protein traffics through the nucleus as an essential step to engage the plasma membrane in preparation for viral budding/release. Comparative studies were performed to assess whether M protein nuclear localization is a common feature of the henipaviruses, including the recently sequenced (although not yet isolated) Ghanaian bat henipavirus (Kumasi virus, GH-M74a virus) and Mojiang virus. Live-cell confocal microscopy revealed that nuclear translocation of GFP-fused M protein is conserved between henipaviruses in both human- and bat-derived cell lines. However, the efficiency of M protein nuclear localization and virus-like particle budding competency varied. Additionally, Cedar virus-, Kumasi virus- and Mojiang virus-M proteins were mutated in a bipartite nuclear localization signal, indicating that a key lysine residue is essential for nuclear import, export and induction of budding events, as previously reported for NiV-M. The results of this study suggest that the M proteins of henipaviruses may utilize a similar nucleocytoplasmic trafficking pathway as an essential step during viral replication in both humans and bats.
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Affiliation(s)
- Elisabeth C McLinton
- Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia
| | - Kylie M Wagstaff
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Alexander Lee
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Gregory W Moseley
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science & Biotechnology Institute, The University of Melbourne, Victoria 3000, Australia
| | - Glenn A Marsh
- CSIRO Biosecurity Flagship, Australian Animal Health Laboratory, Geelong, Victoria 3219, Australia
| | - Lin-Fa Wang
- Programme in Emerging Infectious Diseases, Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Kim G Lieu
- Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia.,Present address: Commonwealth Serum Laboratories Limited, Parkville, Victoria 3052, Australia
| | - Hans J Netter
- Victorian Infectious Diseases Reference Laboratory, Melbourne Health, The Peter Doherty Institute, Victoria 3000, Australia.,Department of Microbiology, Monash University, Clayton, Victoria 3800, Australia
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38
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Fatima S, Wagstaff KM, Lieu KG, Davies RG, Tanaka SS, Yamaguchi YL, Loveland KL, Tam PP, Jans DA. Interactome of the inhibitory isoform of the nuclear transporter Importin 13. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 2017; 1864:546-561. [DOI: 10.1016/j.bbamcr.2016.12.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 11/11/2016] [Accepted: 12/15/2016] [Indexed: 10/20/2022]
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Walker E, Jensen L, Croft S, Wei K, Fulcher AJ, Jans DA, Ghildyal R. Rhinovirus 16 2A Protease Affects Nuclear Localization of 3CD during Infection. J Virol 2016; 90:11032-11042. [PMID: 27681132 PMCID: PMC5126362 DOI: 10.1128/jvi.00974-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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: 06/28/2016] [Accepted: 09/11/2016] [Indexed: 01/08/2023] Open
Abstract
The human rhinovirus (HRV) 3C and 2A proteases (3Cpro and 2Apro, respectively) are critical in HRV infection, as they are required for viral polyprotein processing as well as proteolysing key host factors to facilitate virus replication. Early in infection, 3Cpro is present as its precursor 3CD, which, although the mechanism of subcellular targeting is unknown, is found in the nucleus as well as the cytoplasm. In this study, we use transfected and infected cell systems to show that 2Apro activity is required for 3CD nuclear localization. Using green fluorescent protein (GFP)-tagged forms of 3Cpro, 3D, and mutant derivatives thereof, we show that 3Cpro is located in the cytoplasm and the nucleus, whereas 3CD and 3D are localized predominantly in the cytoplasm, implying that 3D lacks nuclear targeting ability and that 3Cpro activity within 3CD is not sufficient to allow the larger protein into the nucleus. Importantly, by coexpressing mCherry-2Apro fusion proteins, we demonstrate formally that 2Apro activity is required to allow HRV 3CD access to the nucleus. In contrast, mCherry-3Cpro is insufficient to allow 3CD access to the nucleus. Finally, we confirm the relevance of these results to HRV infection by demonstrating that nuclear localization of 3CD correlates with 2Apro activity and not 3Cpro activity, which is observed only later in infection. The results thus define the temporal activities of 2Apro and 3CD/3Cpro activities in HRV serotype16 infection. IMPORTANCE The human rhinovirus genome encodes two proteases, 2A and 3C, as well as a precursor protease, 3CD. These proteases are essential for efficient virus replication. The 3CD protein is found in the nucleus early during infection, though the mechanism of subcellular localization is unknown. Here we show that 2A protease is required for this localization, the 3C protease activity of 3CD is not sufficient to allow 3CD entry into the nucleus, and 3D lacks nuclear targeting ability. This study demonstrates that both 2A and 3C proteases are required for the correct localization of proteins during infection and defines the temporal regulation of 2A and 3CD/3C protease activities during HRV16 infection.
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Affiliation(s)
- Erin Walker
- Centre for Research in Therapeutic Solutions, University of Canberra, Canberra, Australian Capital Territory, Australia
| | - Lora Jensen
- Centre for Research in Therapeutic Solutions, University of Canberra, Canberra, Australian Capital Territory, Australia
| | - Sarah Croft
- Centre for Research in Therapeutic Solutions, University of Canberra, Canberra, Australian Capital Territory, Australia
| | - Kejun Wei
- Centre for Research in Therapeutic Solutions, University of Canberra, Canberra, Australian Capital Territory, Australia
| | - Alex J Fulcher
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
- Monash Micro Imaging, Monash University, Clayton, Victoria, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Reena Ghildyal
- Centre for Research in Therapeutic Solutions, University of Canberra, Canberra, Australian Capital Territory, Australia
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40
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Lundberg L, Pinkham C, de la Fuente C, Brahms A, Shafagati N, Wagstaff KM, Jans DA, Tamir S, Kehn-Hall K. Selective Inhibitor of Nuclear Export (SINE) Compounds Alter New World Alphavirus Capsid Localization and Reduce Viral Replication in Mammalian Cells. PLoS Negl Trop Dis 2016; 10:e0005122. [PMID: 27902702 PMCID: PMC5130180 DOI: 10.1371/journal.pntd.0005122] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [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: 09/24/2015] [Accepted: 10/21/2016] [Indexed: 01/28/2023] Open
Abstract
The capsid structural protein of the New World alphavirus, Venezuelan equine encephalitis virus (VEEV), interacts with the host nuclear transport proteins importin α/β1 and CRM1. Novel selective inhibitor of nuclear export (SINE) compounds, KPT-185, KPT-335 (verdinexor), and KPT-350, target the host's primary nuclear export protein, CRM1, in a manner similar to the archetypical inhibitor Leptomycin B. One major limitation of Leptomycin B is its irreversible binding to CRM1; which SINE compounds alleviate because they are slowly reversible. Chemically inhibiting CRM1 with these compounds enhanced capsid localization to the nucleus compared to the inactive compound KPT-301, as indicated by immunofluorescent confocal microscopy. Differences in extracellular versus intracellular viral RNA, as well as decreased capsid in cell free supernatants, indicated the inhibitors affected viral assembly, which led to a decrease in viral titers. The decrease in viral replication was confirmed using a luciferase-tagged virus and through plaque assays. SINE compounds had no effect on VEEV TC83_Cm, which encodes a mutated form of capsid that is unable to enter the nucleus. Serially passaging VEEV in the presence of KPT-185 resulted in mutations within the nuclear localization and nuclear export signals of capsid. Finally, SINE compound treatment also reduced the viral titers of the related eastern and western equine encephalitis viruses, suggesting that CRM1 maintains a common interaction with capsid proteins across the New World alphavirus genus.
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Affiliation(s)
- Lindsay Lundberg
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Chelsea Pinkham
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Cynthia de la Fuente
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Ashwini Brahms
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Nazly Shafagati
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
| | - Kylie M. Wagstaff
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - David A. Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Sharon Tamir
- Karyopharm Therapeutics Inc., Massachusetts, United States of America
| | - Kylene Kehn-Hall
- National Center for Biodefense and Infectious Diseases, School of Systems Biology, George Mason University, Manassas, Virginia, United States of America
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Audsley MD, Jans DA, Moseley GW. Nucleocytoplasmic trafficking of Nipah virus W protein involves multiple discrete interactions with the nuclear import and export machinery. Biochem Biophys Res Commun 2016; 479:429-433. [PMID: 27622322 DOI: 10.1016/j.bbrc.2016.09.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [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: 09/01/2016] [Accepted: 09/09/2016] [Indexed: 10/21/2022]
Abstract
Paramyxoviruses replicate in the cytoplasm with no obvious requirement to interact with the nucleus. Nevertheless, the W protein of the highly lethal bat-borne paramyxovirus Nipah virus (NiV) is known to undergo specific targeting to the nucleus, mediated by a single nuclear localisation signal (NLS) within the C-terminal domain. Here, we report for the first time that additional sites modulate nucleocytoplasmic localisation of W. We show that the N-terminal domain interacts with importin α1 and contributes to nuclear accumulation of W, indicative of a novel N-terminal NLS. We also find that W undergoes exportin-1 mediated nuclear export, dependent on a leucine at position 174. Together, these data enable significant revision of the generally accepted model of W trafficking, with implications for understanding of the mechanisms of NiV immune evasion.
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Affiliation(s)
- Michelle D Audsley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Gregory W Moseley
- Department of Biochemistry and Molecular Biology, BIO21 Molecular Science and Biotechnology Institute, 30 Flemington Road, The University of Melbourne, VIC, 3010, Australia.
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42
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Brice A, Whelan DR, Ito N, Shimizu K, Wiltzer-Bach L, Lo CY, Blondel D, Jans DA, Bell TDM, Moseley GW. Quantitative Analysis of the Microtubule Interaction of Rabies Virus P3 Protein: Roles in Immune Evasion and Pathogenesis. Sci Rep 2016; 6:33493. [PMID: 27649849 PMCID: PMC5030706 DOI: 10.1038/srep33493] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 08/25/2016] [Indexed: 12/21/2022] Open
Abstract
Although microtubules (MTs) are known to have important roles in intracellular transport of many viruses, a number of reports suggest that specific viral MT-associated proteins (MAPs) target MTs to subvert distinct MT-dependent cellular processes. The precise functional importance of these interactions and their roles in pathogenesis, however, remain largely unresolved. To assess the association with disease of the rabies virus (RABV) MAP, P3, we quantitatively compared the phenotypes of P3 from a pathogenic RABV strain, Nishigahara (Ni) and a non-pathogenic Ni-derivative strain, Ni-CE. Using confocal/live-cell imaging and dSTORM super-resolution microscopy to quantify protein interactions with the MT network and with individual MT filaments, we found that the interaction by Ni-CE-P3 is significantly impaired compared with Ni-P3. This correlated with an impaired capacity to effect association of the transcription factor STAT1 with MTs and to antagonize interferon (IFN)/STAT1-dependent antiviral signaling. Importantly, we identified a single mutation in Ni-CE-P3 that is sufficient to inhibit MT-association and IFN-antagonist function of Ni-P3, and showed that this mutation alone attenuates the pathogenicity of RABV. These data provide evidence that the viral protein-MT interface has important roles in pathogenesis, suggesting that this interface could provide targets for vaccine/antiviral drug development.
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Affiliation(s)
- Aaron Brice
- Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, 3010, Australia
| | - Donna R Whelan
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Naoto Ito
- Laboratory of Zoonotic Diseases, Faculty of Applied Biological Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.,The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Kenta Shimizu
- The United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
| | - Linda Wiltzer-Bach
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.,Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Camden Y Lo
- Monash Micro Imaging, 27-31 Wright Street, Clayton, Victoria, 3168, Australia
| | - Danielle Blondel
- Unité de Virologie Moleculaire et Structurale, CNRS, UPR 3296, 91198 Gif sur Yvette Cedex, France
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Toby D M Bell
- School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Gregory W Moseley
- Viral Pathogenesis Laboratory, Department of Biochemistry and Molecular Biology, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, 3010, Australia
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43
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Tay MYF, Smith K, Ng IHW, Chan KWK, Zhao Y, Ooi EE, Lescar J, Luo D, Jans DA, Forwood JK, Vasudevan SG. The C-terminal 18 Amino Acid Region of Dengue Virus NS5 Regulates its Subcellular Localization and Contains a Conserved Arginine Residue Essential for Infectious Virus Production. PLoS Pathog 2016; 12:e1005886. [PMID: 27622521 PMCID: PMC5021334 DOI: 10.1371/journal.ppat.1005886] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [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: 05/14/2016] [Accepted: 08/22/2016] [Indexed: 11/24/2022] Open
Abstract
Dengue virus NS5 is the most highly conserved amongst the viral non-structural proteins and is responsible for capping, methylation and replication of the flavivirus RNA genome. Interactions of NS5 with host proteins also modulate host immune responses. Although replication occurs in the cytoplasm, an unusual characteristic of DENV2 NS5 is that it localizes to the nucleus during infection with no clear role in replication or pathogenesis. We examined NS5 of DENV1 and 2, which exhibit the most prominent difference in nuclear localization, employing a combination of functional and structural analyses. Extensive gene swapping between DENV1 and 2 NS5 identified that the C-terminal 18 residues (Cter18) alone was sufficient to direct the protein to the cytoplasm or nucleus, respectively. The low micromolar binding affinity between NS5 Cter18 and the nuclear import receptor importin-alpha (Impα), allowed their molecular complex to be purified, crystallised and visualized at 2.2 Å resolution using x-ray crystallography. Structure-guided mutational analysis of this region in GFP-NS5 clones of DENV1 or 2 and in a DENV2 infectious clone reveal residues important for NS5 subcellular localization. Notably, the trans conformation adopted by Pro-884 allows proper presentation for binding Impα and mutating this proline to Thr, as present in DENV1 NS5, results in mislocalizaion of NS5 to the cytoplasm without compromising virus fitness. In contrast, a single mutation to alanine at NS5 position R888, a residue conserved in all flaviviruses, resulted in a completely non-viable virus, and the R888K mutation led to a severely attenuated phentoype, even though NS5 was located in the nucleus. R888 forms a hydrogen bond with Y838 that is also conserved in all flaviviruses. Our data suggests an evolutionarily conserved function for NS5 Cter18, possibly in RNA interactions that are critical for replication, that is independent of its role in subcellular localization. DENV NS5 is critical for virus RNA replication and an important drug target based on its high sequence conservation across serotypes, and the successful development of potent drugs that target the homologous NS5B of hepatitis C virus. NS5 also mediates other functions that are important for innate and adaptive immune responses by the infected host. Extensive gene swapping and functional analyses between NS5 of DENV serotypes 1 and 2, that are the two most disparate in terms of nuclear vs cytoplasmic localization of NS5 identified the last 18 amino acid residues of the ~900 amino-acid residues long protein to be responsible for subcellular localization. Because this region is very flexible and not easily seen in crystal structures of DENV NS5, co-crystals of the newly discovered peptide region with importin α were obtained. Structure-based mutations introduced into a DENV2 infectious clone showed that the proline to threonine at position 884 resulted in NS5 being mostly cytoplasmic without affecting virus replication. However mutation of arginine 888, which is conserved in all flaviviruses, to alanine resulted in a completely non-viable virus, suggesting that the C-terminal region is essential for NS5 function irrespective of its role in subcellular location.
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Affiliation(s)
- Moon Y. F. Tay
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Kate Smith
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Ivan H. W. Ng
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Kitti W. K. Chan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yongqian Zhao
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
| | - Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Julien Lescar
- School of Biological Sciences, Nanyang Technological University, Singapore
- UPMC UMRS CR7—CNRS ERL 8255-INSERM U1135 Centre d’Immunologie et des Maladies Infectieuses. Centre Hospitalier Universitaire Pitié-Salpêtrière, Faculté de Médecine Pierre et Marie Curie, Paris, France
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore
| | - David A. Jans
- Nuclear Signalling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Jade K. Forwood
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Subhash G. Vasudevan
- Program in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- * E-mail:
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44
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Audsley MD, Jans DA, Moseley GW. Roles of nuclear trafficking in infection by cytoplasmic negative-strand RNA viruses: paramyxoviruses and beyond. J Gen Virol 2016; 97:2463-2481. [PMID: 27498841 DOI: 10.1099/jgv.0.000575] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Genome replication and virion production by most negative-sense RNA viruses (NSVs) occurs exclusively in the cytoplasm, but many NSV-expressed proteins undergo active nucleocytoplasmic trafficking via signals that exploit cellular nuclear transport pathways. Nuclear trafficking has been reported both for NSV accessory proteins (including isoforms of the rabies virus phosphoprotein, and V, W and C proteins of paramyxoviruses) and for structural proteins. Trafficking of the former is thought to enable accessory functions in viral modulation of antiviral responses including the type I IFN system, but the intranuclear roles of structural proteins such as nucleocapsid and matrix proteins, which have critical roles in extranuclear replication and viral assembly, are less clear. Nevertheless, nuclear trafficking of matrix protein has been reported to be critical for efficient production of Nipah virus and Respiratory syncytial virus, and nuclear localization of nucleocapsid protein of several morbilliviruses has been linked to mechanisms of immune evasion. Together, these data point to the nucleus as a significant host interface for viral proteins during infection by NSVs with otherwise cytoplasmic life cycles. Importantly, several lines of evidence now suggest that nuclear trafficking of these proteins may be critical to pathogenesis and thus could provide new targets for vaccine development and antiviral therapies.
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Affiliation(s)
- Michelle D Audsley
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Gregory W Moseley
- Department of Biochemistry and Molecular Biology, BIO21 Molecular Science and Biotechnology Institute, University of Melbourne, VIC 3000, Australia
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Alvisi G, Jans DA. Secret life of importin-β; solenoid flexibility as the key to transport through the nuclear pore. Acta Crystallogr D Struct Biol 2016; 72:703-4. [PMID: 27303790 DOI: 10.1107/s2059798316008263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Gualtiero Alvisi
- Department of Molecular Medicine, University of Padua, 35121 Padua, Italy
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, 3800 Clayton, Victoria, Australia
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Götz V, Magar L, Dornfeld D, Giese S, Pohlmann A, Höper D, Kong BW, Jans DA, Beer M, Haller O, Schwemmle M. Corrigendum: Influenza A viruses escape from MxA restriction at the expense of efficient nuclear vRNP import. Sci Rep 2016; 6:25428. [PMID: 27156930 PMCID: PMC4860781 DOI: 10.1038/srep25428] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Affiliation(s)
- Gualtiero Alvisi
- a Department of Molecular Medicine University of Padua; Padua. Italy
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Loveland KL, Major AT, Butler R, Young JC, Jans DA, Miyamoto Y. Putting things in place for fertilization: discovering roles for importin proteins in cell fate and spermatogenesis. Asian J Androl 2016; 17:537-44. [PMID: 25994647 PMCID: PMC4492042 DOI: 10.4103/1008-682x.154310] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Importin proteins were originally characterized for their central role in protein transport through the nuclear pores, the only intracellular entry to the nucleus. This vital function must be tightly regulated to control access by transcription factors and other nuclear proteins to genomic DNA, to achieve appropriate modulation of cellular behaviors affecting cell fate. Importin-mediated nucleocytoplasmic transport relies on their specific recognition of cargoes, with each importin binding to distinct and overlapping protein subsets. Knowledge of importin function has expanded substantially in regard to three key developmental systems: embryonic stem cells, muscle cells and the germ line. In the decade since the potential for regulated nucleocytoplasmic transport to contribute to spermatogenesis was proposed, we and others have shown that the importins that ferry transcription factors into the nucleus perform additional roles, which control cell fate. This review presents key findings from studies of mammalian spermatogenesis that reveal potential new pathways by which male fertility and infertility arise. These studies of germline genesis illuminate new ways in which importin proteins govern cellular differentiation, including via directing proteins to distinct intracellular compartments and by determining cellular stress responses.
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Affiliation(s)
- Kate L Loveland
- Department of Biochemistry and Molecular Biology;Department of Anatomy and Developmental Biology, Monash University; Hudson Institute of Medical Research, Monash Medical Centre; School of Clinical Sciences, Monash University, Clayton, VIC, Australia,
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Götz V, Magar L, Dornfeld D, Giese S, Pohlmann A, Höper D, Kong BW, Jans DA, Beer M, Haller O, Schwemmle M. Influenza A viruses escape from MxA restriction at the expense of efficient nuclear vRNP import. Sci Rep 2016; 6:23138. [PMID: 26988202 PMCID: PMC4796820 DOI: 10.1038/srep23138] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 03/01/2016] [Indexed: 01/03/2023] Open
Abstract
To establish a new lineage in the human population, avian influenza A viruses (AIV) must overcome the intracellular restriction factor MxA. Partial escape from MxA restriction can be achieved when the viral nucleoprotein (NP) acquires the critical human-adaptive amino acid residues 100I/V, 283P, and 313Y. Here, we show that introduction of these three residues into the NP of an avian H5N1 virus renders it genetically unstable, resulting in viruses harboring additional single mutations, including G16D. These substitutions restored genetic stability yet again yielded viruses with varying degrees of attenuation in mammalian and avian cells. Additionally, most of the mutant viruses lost the capacity to escape MxA restriction, with the exception of the G16D virus. We show that MxA escape is linked to attenuation by demonstrating that the three substitutions promoting MxA escape disturbed intracellular trafficking of incoming viral ribonucleoprotein complexes (vRNPs), thereby resulting in impaired nuclear import, and that the additional acquired mutations only partially compensate for this import block. We conclude that for adaptation to the human host, AIV must not only overcome MxA restriction but also an associated block in nuclear vRNP import. This inherent difficulty may partially explain the frequent failure of AIV to become pandemic.
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Affiliation(s)
- Veronika Götz
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
| | - Linda Magar
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
| | - Dominik Dornfeld
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
| | - Sebastian Giese
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
| | - Anne Pohlmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, 17493 Greifswald-Insel Riems, Germany
| | - Dirk Höper
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, 17493 Greifswald-Insel Riems, Germany
| | - Byung-Whi Kong
- Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - David A Jans
- Nuclear Signaling Laboratory, Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Victoria, Australia
| | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, 17493 Greifswald-Insel Riems, Germany
| | - Otto Haller
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
| | - Martin Schwemmle
- Institute of Virology, University Medical Center Freiburg, D-79104 Freiburg, Germany
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Fulcher AJ, Sivakumaran H, Jin H, Rawle DJ, Harrich D, Jans DA. The protein arginine methyltransferase PRMT6 inhibits HIV-1 Tat nucleolar retention. Biochim Biophys Acta 2016; 1863:254-62. [PMID: 26611710 DOI: 10.1016/j.bbamcr.2015.11.019] [Citation(s) in RCA: 12] [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] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 10/30/2015] [Accepted: 11/18/2015] [Indexed: 10/22/2022]
Abstract
The human immunodeficiency virus (HIV)-1 transactivator protein Tat is known to play a key role in HIV infection, integrally related to its role in the host cell nucleus/nucleolus. Here we show for the first time that Tat localisation can be modulated by specific methylation, whereby overexpression of active but not catalytically inactive PRMT6 methyltransferase specifically leads to exclusion of Tat from the nucleolus. An R52/53A mutated Tat derivative does not show this redistribution, implying that R52/53, within Tat's nuclear/nucleolar localisation signal, are the targets of PRMT6 activity. Analysis using fluorescence recovery after photobleaching indicate that Tat nucleolar accumulation is largely through binding to nucleolar components, with methylation of Tat by PRMT6 preventing this. To our knowledge, this is the first report of specific protein methylation inhibiting nucleolar retention.
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Affiliation(s)
- Alex J Fulcher
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; Monash Micro Imaging, Monash University, Clayton, Victoria 3800, Australia
| | - Haran Sivakumaran
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland 4029, Australia; The University of Queensland, School of Population Health, Herston, Queensland 4072, Australia
| | - Hongping Jin
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland 4029, Australia
| | - Daniel J Rawle
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland 4029, Australia; School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - David Harrich
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland 4029, Australia; Griffith Medical Research College, a joint program of Griffith University and the Queensland Institute of Medical Research, Queensland, Australia
| | - David A Jans
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; ARC Centre of Excellence for Biotechnology and Development, Australia.
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