1
|
Arita M. An efficient trans complementation system for in vivo replication of defective poliovirus mutants. J Virol 2024:e0052324. [PMID: 38837378 DOI: 10.1128/jvi.00523-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 05/13/2024] [Indexed: 06/07/2024] Open
Abstract
The picornavirus genome encodes a large, single polyprotein that is processed by viral proteases to form an active replication complex. The replication complex is formed with the viral genome, host proteins, and viral proteins that are produced/translated directly from each of the viral genomes (viral proteins provided in cis). Efficient complementation in vivo of replication complex formation by viral proteins provided in trans, thus exogenous or ectopically expressed viral proteins, remains to be demonstrated. Here, we report an efficient trans complementation system for the replication of defective poliovirus (PV) mutants by a viral polyprotein precursor in HEK293 cells. Viral 3AB in the polyprotein, but not 2BC, was processed exclusively in cis. Replication of a defective PV replicon mutant, with a disrupted cleavage site for viral 3Cpro protease between 3Cpro and 3Dpol (3C/D[A/G] mutant) could be rescued by a viral polyprotein provided in trans. Only a defect of 3Dpol activity of the replicon could be rescued in trans; inactivating mutations in 2CATPase/hel, 3B, and 3Cpro of the replicon completely abrogated the trans-rescued replication. An intact N-terminus of the 3Cpro domain of the 3CDpro provided in trans was essential for the trans-active function. By using this trans complementation system, a high-titer defective PV pseudovirus (PVpv) (>107 infectious units per mL) could be produced with the defective mutants, whose replication was completely dependent on trans complementation. This work reveals potential roles of exogenous viral proteins in PV replication and offers insights into protein/protein interaction during picornavirus infection. IMPORTANCE Viral polyprotein processing is an elaborately controlled step by viral proteases encoded in the polyprotein; fully processed proteins and processing intermediates need to be correctly produced for replication, which can be detrimentally affected even by a small modification of the polyprotein. Purified/isolated viral proteins can retain their enzymatic activities required for viral replication, such as protease, helicase, polymerase, etc. However, when these proteins of picornavirus are exogenously provided (provided in trans) to the viral replication complex with a defective viral genome, replication is generally not rescued/complemented, suggesting the importance of viral proteins endogenously provided (provided in cis) to the replication complex. In this study, I discovered that only the viral polymerase activity of poliovirus (PV) (the typical member of picornavirus family) could be efficiently rescued by exogenously expressed viral proteins. The current study reveals potential roles for exogenous viral proteins in viral replication and offers insights into interactions during picornavirus infection.
Collapse
Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, Musashimurayama-shi, Tokyo, Japan
| |
Collapse
|
2
|
Sang Y, Niu C, Xu J, Zhu T, You S, Wang J, Zhang L, Du X, Zhang H. PI4KIIIβ-Mediated Phosphoinositides Metabolism Regulates Function of the VTA Dopaminergic Neurons and Depression-Like Behavior. J Neurosci 2024; 44:e0555232024. [PMID: 38267258 PMCID: PMC10941068 DOI: 10.1523/jneurosci.0555-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 12/18/2023] [Accepted: 01/11/2024] [Indexed: 01/26/2024] Open
Abstract
Phosphoinositides, including phosphatidylinositol-4,5-bisphosphate (PIP2), play a crucial role in controlling key cellular functions such as membrane and vesicle trafficking, ion channel, and transporter activity. Phosphatidylinositol 4-kinases (PI4K) are essential enzymes in regulating the turnover of phosphoinositides. However, the functional role of PI4Ks and mediated phosphoinositide metabolism in the central nervous system has not been fully revealed. In this study, we demonstrated that PI4KIIIβ, one of the four members of PI4Ks, is an important regulator of VTA dopaminergic neuronal activity and related depression-like behavior of mice by controlling phosphoinositide turnover. Our findings provide new insights into possible mechanisms and potential drug targets for neuropsychiatric diseases, including depression. Both sexes were studied in basic behavior tests, but only male mice could be used in the social defeat depression model.
Collapse
Affiliation(s)
- Yuqi Sang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Chenxu Niu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Jiaxi Xu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Department of Physiology and Pathophysiology, Xi'an Jiaotong University Health Science Center, Xi'an, Shanxi 710061, China
| | - Tiantian Zhu
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Shuangzhu You
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Jing Wang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Ludi Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Xiaona Du
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Hailin Zhang
- Department of Pharmacology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- The Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Collaborative Innovation Center of Hebei Province for Mechanism, Diagnosis and Treatment of Neuropsychiatric Diseases, Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Department of Psychiatry, The First Hospital of Hebei Medical University, Mental Health Institute of Hebei Medical University, Shijiazhuang, Hebei 050000, China
| |
Collapse
|
3
|
Zhao X, Hu Y, Zhao J, Liu Y, Ma X, Chen H, Xing Y. Role of protein Post-translational modifications in enterovirus infection. Front Microbiol 2024; 15:1341599. [PMID: 38596371 PMCID: PMC11002909 DOI: 10.3389/fmicb.2024.1341599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 01/18/2024] [Indexed: 04/11/2024] Open
Abstract
Enteroviruses (EVs) are the main cause of a number of neurological diseases. Growing evidence has revealed that successful infection with enteroviruses is highly dependent on the host machinery, therefore, host proteins play a pivotal role in viral infections. Both host and viral proteins can undergo post-translational modification (PTM) which can regulate protein activity, stability, solubility and interactions with other proteins; thereby influencing various biological processes, including cell metabolism, metabolic, signaling pathways, cell death, and cancer development. During viral infection, both host and viral proteins regulate the viral life cycle through various PTMs and different mechanisms, including the regulation of host cell entry, viral protein synthesis, genome replication, and the antiviral immune response. Therefore, protein PTMs play important roles in EV infections. Here, we review the role of various host- and virus-associated PTMs during enterovirus infection.
Collapse
Affiliation(s)
- Xiaohui Zhao
- Department of Pathogen Biology, School of Medicine, Qinghai University, Qinghai, China
| | - Yibo Hu
- Department of Orthopaedic Trauma, The Affiliated Hospital of Qinghai University, Qinghai, China
| | - Jun Zhao
- Department of Pathogen Biology, School of Medicine, Qinghai University, Qinghai, China
| | - Yan Liu
- Department of Immunology, School of Medicine, Qinghai, China
| | - Xueman Ma
- Department of Traditional Chinese Medicine, School of Medicine, Qinghai University, Qinghai, China
| | - Hongru Chen
- Department of Public Health, School of Medicine, Qinghai University, Qinghai, China
| | - Yonghua Xing
- Department of Genetics, School of Medicine, Qinghai University, Qinghai, China
| |
Collapse
|
4
|
Arita M, Fuchino H. Characterization of Anti-Poliovirus Compounds Isolated from Edible Plants. Viruses 2023; 15:v15040903. [PMID: 37112883 PMCID: PMC10145814 DOI: 10.3390/v15040903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/29/2023] Open
Abstract
Poliovirus (PV) is the causative agent of poliomyelitis and is a target of the global eradication programs of the World Health Organization (WHO). After eradication of type 2 and 3 wild-type PVs, vaccine-derived PV remains a substantial threat against the eradication as well as type 1 wild-type PV. Antivirals could serve as an effective means to suppress the outbreak; however, no anti-PV drugs have been approved at present. Here, we screened for effective anti-PV compounds in a library of edible plant extracts (a total of 6032 extracts). We found anti-PV activity in the extracts of seven different plant species. We isolated chrysophanol and vanicoside B (VCB) as the identities of the anti-PV activities of the extracts of Rheum rhaponticum and Fallopia sachalinensis, respectively. VCB targeted the host PI4KB/OSBP pathway for its anti-PV activity (EC50 = 9.2 μM) with an inhibitory effect on in vitro PI4KB activity (IC50 = 5.0 μM). This work offers new insights into the anti-PV activity in edible plants that may serve as potent antivirals for PV infection.
Collapse
Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi 208-0011, Tokyo, Japan
| | - Hiroyuki Fuchino
- Research Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, 1-2 Hachimandai, Tsukuba 305-0843, Ibaraki, Japan
| |
Collapse
|
5
|
Arita M. Essential Domains of Oxysterol-Binding Protein Required for Poliovirus Replication. Viruses 2022; 14:v14122672. [PMID: 36560676 PMCID: PMC9786093 DOI: 10.3390/v14122672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/25/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022] Open
Abstract
Oxysterol-binding protein (OSBP) is a host factor required for enterovirus (EV) replication. OSBP locates at membrane contact site and acts as a lipid exchanger of cholesterol and phosphatidylinositol 4-phosphate (PI4P) between cellular organelles; however, the essential domains required for the viral replication remain unknown. In this study, we define essential domains of OSBP for poliovirus (PV) replication by a functional dominance assay with a series of deletion variants of OSBP. We show that the pleckstrin homology domain (PHD) and the ligand-binding domain, but not the N-terminal intrinsically disordered domain, coiled-coil region, or the FFAT motif, are essential for PV replication. The PHD serves as the primary determinant of OSBP targeting to the replication organelle in the infected cells. These results suggest that not all the domains that support important biological functions of OSBP are essential for the viral replication.
Collapse
Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan
| |
Collapse
|
6
|
Kobayashi J, Arita M, Sakai S, Kojima H, Senda M, Senda T, Hanada K, Kato R. Ligand Recognition by the Lipid Transfer Domain of Human OSBP Is Important for Enterovirus Replication. ACS Infect Dis 2022; 8:1161-1170. [PMID: 35613096 DOI: 10.1021/acsinfecdis.2c00108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Oxysterol-binding protein (OSBP), which transports cholesterol and phosphatidylinositol 4-monophosphate (PtdIns[4]P) between different organelles, serves as a conserved host factor for the replication of various viruses, and OSBP inhibitors exhibit antiviral effects. Here, we determined the crystal structure of the lipid transfer domain of human OSBP in complex with endogenous cholesterol. The hydrocarbon tail and tetracyclic ring of cholesterol interact with the hydrophobic tunnel of OSBP, and the hydroxyl group of cholesterol forms a hydrogen bond network at the bottom of the tunnel. Systematic mutagenesis of the ligand-binding region revealed that M446W and L590W substitutions confer functional tolerance to an OSBP inhibitor, T-00127-HEV2. Employing the M446W variant as a functional replacement for the endogenous OSBP in the presence of T-00127-HEV2, we have identified previously unappreciated amino acid residues required for viral replication. The combined use of the inhibitor and the OSBP variant will be useful in elucidating the enigmatic in vivo functions of OSBP.
Collapse
Affiliation(s)
- Jun Kobayashi
- Structural Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo 208-0011, Japan
| | - Shota Sakai
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Hirotatsu Kojima
- Drug Discovery Initiative, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Miki Senda
- Structural Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Toshiya Senda
- Structural Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Kentaro Hanada
- Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Ryuichi Kato
- Structural Biology Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| |
Collapse
|
7
|
High-Order Epistasis and Functional Coupling of Infection Steps Drive Virus Evolution toward Independence from a Host Pathway. Microbiol Spectr 2021; 9:e0080021. [PMID: 34468191 PMCID: PMC8557862 DOI: 10.1128/spectrum.00800-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The phosphatidylinositol-4 kinase IIIβ (PI4KB)/oxysterol-binding protein (OSBP) family I pathway serves as an essential host pathway for the formation of viral replication complex for viral plus-strand RNA synthesis; however, poliovirus (PV) could evolve toward substantial independence from this host pathway with four mutations. Recessive epistasis of the two mutations (3A-R54W and 2B-F17L) is essential for viral RNA replication. Quantitative analysis of effects of the other two mutations (2B-Q20H and 2C-M187V) on each step of infection reveals functional couplings between viral replication, growth, and spread conferred by the 2B-Q20H mutation, while no enhancing effect was conferred by the 2C-M187V mutation. The effects of the 2B-Q20H mutation occur only via another recessive epistasis between the 3A-R54W/2B-F17L mutations. These mutations confer enhanced replication in PI4KB/OSBP-independent infection concomitantly with an increased ratio of viral plus-strand RNA to the minus-strand RNA. This work reveals the essential roles of the functional coupling and high-order, multi-tiered recessive epistasis in viral evolution toward independence from an obligatory host pathway. IMPORTANCE Each virus has a different strategy for its replication, which requires different host factors. Enterovirus, a model RNA virus, requires host factors PI4KB and OSBP, which form an obligatory functional axis to support viral replication. In an experimental evolution system in vitro, virus mutants that do not depend on these host factors could arise only with four mutations. The two mutations (3A-R54W and 2B-F17L) are required for the replication but are not sufficient to support efficient infection. Another mutation (2B-Q20H) is essential for efficient spread of the virus. The order of introduction of the mutations in the viral genome is essential (known as “epistasis”), and functional couplings of infection steps (i.e., viral replication, growth, and spread) have substantial roles to show the effects of the 2B-Q20H mutation. These observations would provide novel insights into an evolutionary pathway of the virus to require host factors for infection.
Collapse
|
8
|
Li YP, Mikrani R, Hu YF, Faran Ashraf Baig MM, Abbas M, Akhtar F, Xu M. Research progress of phosphatidylinositol 4-kinase and its inhibitors in inflammatory diseases. Eur J Pharmacol 2021; 907:174300. [PMID: 34217706 DOI: 10.1016/j.ejphar.2021.174300] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 06/24/2021] [Accepted: 06/30/2021] [Indexed: 01/08/2023]
Abstract
Phosphatidylinositol 4-kinase (PI4K) is a lipid kinase that can catalyze the transfer of phosphate group from ATP to the inositol ring of phosphatidylinositol (PtdIns) resulting in the phosphorylation of PtdIns at 4-OH sites, to generate phosphatidylinositol 4-phosphate (PI4P). Studies on biological functions reveal that PI4K is closely related to the occurrence and development of various inflammatory diseases such as obesity, cancer, viral infections, malaria, Alzheimer's disease, etc. PI4K-related inhibitors have been found to have the effects of inhibiting virus replication, anti-cancer, treating malaria and reducing rejection in organ transplants, among which MMV390048, an anti-malaria drug, has entered phase II clinical trial. This review discusses the classification, structure, distribution and related inhibitors of PI4K and their role in the progression of cancer, viral replication, and other inflammation induced diseases to explore their potential as therapeutic targets.
Collapse
Affiliation(s)
- Yan-Ping Li
- Department of Clinical Pharmacy, School of Preclinical Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Reyaj Mikrani
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria 3052, Australia
| | - Yi-Fan Hu
- Department of Clinical Pharmacy, School of Preclinical Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Mirza Muhammad Faran Ashraf Baig
- Laboratory of Biomedical Engineering for Novel Bio-functional and Pharmaceutical Nano-materials, Prince Philip Dental Hospital, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, 999077, China
| | - Muhammad Abbas
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210023, PR China
| | - Fahad Akhtar
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China; School of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ming Xu
- Department of Clinical Pharmacy, School of Preclinical Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| |
Collapse
|
9
|
Novel capsid binder and PI4KIIIbeta inhibitors for EV-A71 replication inhibition. Sci Rep 2021; 11:9719. [PMID: 33958691 PMCID: PMC8102518 DOI: 10.1038/s41598-021-89271-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 04/16/2021] [Indexed: 11/22/2022] Open
Abstract
The Hand, Foot and Mouth Disease (HFMD) is a highly contagious viral illness generally manifests as a mild disease in young children and immunocompromised adults. It has however emerged as a significant public health threat in recent years as outbreaks have been occurring regularly, especially in the Asia–Pacific. The disease can result from infections by a wide variety of human enteroviruses, particularly, Enterovirus A71 (EV-A71) has garnered more attention due to its association with severe disease in infected patients. Despite the potential to result severe neurological complications or even fatality, there is currently no effective antiviral for treatment of EV-A71 infections and the only vaccines available are restricted to distribution in China. In this study, we report the in vitro and in vivo evaluation of two candidate antiviral compounds active against EV-A71, a viral capsid inhibitor (G197) and a novel host-targeting phosphatidylinositol 4-kinase III beta inhibitor (N373) which, especially when used in combination, can significantly improve the survival and pathology of infected mice.
Collapse
|
10
|
Jackson T, Belsham GJ. Picornaviruses: A View from 3A. Viruses 2021; 13:v13030456. [PMID: 33799649 PMCID: PMC7999760 DOI: 10.3390/v13030456] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 12/14/2022] Open
Abstract
Picornaviruses are comprised of a positive-sense RNA genome surrounded by a protein shell (or capsid). They are ubiquitous in vertebrates and cause a wide range of important human and animal diseases. The genome encodes a single large polyprotein that is processed to structural (capsid) and non-structural proteins. The non-structural proteins have key functions within the viral replication complex. Some, such as 3Dpol (the RNA dependent RNA polymerase) have conserved functions and participate directly in replicating the viral genome, whereas others, such as 3A, have accessory roles. The 3A proteins are highly divergent across the Picornaviridae and have specific roles both within and outside of the replication complex, which differ between the different genera. These roles include subverting host proteins to generate replication organelles and inhibition of cellular functions (such as protein secretion) to influence virus replication efficiency and the host response to infection. In addition, 3A proteins are associated with the determination of host range. However, recent observations have challenged some of the roles assigned to 3A and suggest that other viral proteins may carry them out. In this review, we revisit the roles of 3A in the picornavirus life cycle. The 3AB precursor and mature 3A have distinct functions during viral replication and, therefore, we have also included discussion of some of the roles assigned to 3AB.
Collapse
Affiliation(s)
- Terry Jackson
- The Pirbright Institute, Pirbright, Woking, Surrey GU24 0NF, UK;
| | - Graham J. Belsham
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark
- Correspondence:
| |
Collapse
|
11
|
Wang SH, Wang K, Zhao K, Hua SC, Du J. The Structure, Function, and Mechanisms of Action of Enterovirus Non-structural Protein 2C. Front Microbiol 2020; 11:615965. [PMID: 33381104 PMCID: PMC7767853 DOI: 10.3389/fmicb.2020.615965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 11/23/2020] [Indexed: 12/16/2022] Open
Abstract
Enteroviruses are a group of RNA viruses belonging to the family Picornaviridae. They include human enterovirus groups A, B, C, and D as well as non-human enteroviruses. Enterovirus infections can lead to hand, foot, and mouth disease and herpangina, whose clinical manifestations are often mild, although some strains can result in severe neurological complications such as encephalitis, myocarditis, meningitis, and poliomyelitis. To date, research on enterovirus non-structural proteins has mainly focused on the 2A and 3C proteases and 3D polymerase. However, another non-structural protein, 2C, is the most highly conserved protein, and plays a vital role in the enterovirus life cycle. There are relatively few studies on this protein. Previous studies have demonstrated that enterovirus 2C is involved in virus uncoating, host cell membrane rearrangements, RNA replication, encapsidation, morphogenesis, ATPase, helicase, and chaperoning activities. Despite ongoing research, little is known about the pathogenesis of enterovirus 2C proteins in viral replication or in the host innate immune system. In this review, we discuss and summarize the current understanding of the structure, function, and mechanism of the enterovirus 2C proteins, focusing on the key mutations and motifs involved in viral infection, replication, and immune regulation. We also focus on recent progress in research into the role of 2C proteins in regulating the pattern recognition receptors and type I interferon signaling pathway to facilitate viral replication. Given these functions and mechanisms, the potential application of the 2C proteins as a target for anti-viral drug development is also discussed. Future studies will focus on the determination of more crystal structures of enterovirus 2C proteins, which might provide more potential targets for anti-viral drug development against enterovirus infections.
Collapse
Affiliation(s)
- Shao-Hua Wang
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Kuan Wang
- Department of Neurotrauma, The First Hospital of Jilin University, Changchun, China
| | - Ke Zhao
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China
| | - Shu-Cheng Hua
- Department of Internal Medicine, The First Hospital of Jilin University, Changchun, China
| | - Juan Du
- Institute of Virology and AIDS Research, The First Hospital of Jilin University, Changchun, China.,Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
12
|
Arita M, Bigay J. Poliovirus Evolution toward Independence from the Phosphatidylinositol-4 Kinase III β/Oxysterol-Binding Protein Family I Pathway. ACS Infect Dis 2019; 5:962-973. [PMID: 30919621 DOI: 10.1021/acsinfecdis.9b00038] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Phosphatidylinositol-4 kinase III β (PI4KB) and oxysterol-binding protein (OSBP) family I provide a conserved host pathway required for enterovirus replication. Here, we analyze the role and essentiality of this pathway in enterovirus replication. Phosphatidylinositol 4-phosphate (PI4P) production and cholesterol accumulation in the replication organelle (RO) are severely suppressed in cells infected with a poliovirus (PV) mutant isolated from a PI4KB-knockout cell line (RD[Δ PI4KB]). Major determinants of the mutant for infectivity in RD(Δ PI4KB) cells map to the A5270U(3A-R54W) and U3881C(2B-F17L) mutations. The 3A mutation is required for PI4KB-independent development of RO. The 2B mutation rather sensitizes PV to PI4KB/OSBP inhibitors by itself but confers substantially complete resistance to the inhibitors with the 3A mutation. The 2B mutation also confers hypersensitivity to interferon alpha treatment on PV. These suggest that the PI4KB/OSBP pathway is not necessarily essential for enterovirus replication in vitro. This work supports a two-step resistance model of enterovirus to PI4KB/OSBP inhibitors involving unique recessive epistasis of 3A and 2B and offers insights into a potential evolutionary pathway of enterovirus toward independence from the PI4KB/OSBP pathway.
Collapse
Affiliation(s)
- Minetaro Arita
- Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Joëlle Bigay
- Université Côte d’Azur, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, Valbonne 06560, France
| |
Collapse
|
13
|
Dial CN, Tate PM, Kicmal TM, Mounce BC. Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity. Viruses 2019; 11:E403. [PMID: 31052199 PMCID: PMC6563312 DOI: 10.3390/v11050403] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 04/26/2019] [Accepted: 04/26/2019] [Indexed: 01/16/2023] Open
Abstract
Polyamines are small positively-charged molecules abundant in eukaryotic cells that are crucial to RNA virus replication. In eukaryotic cells, polyamines facilitate processes such as transcription, translation, and DNA replication, and viruses similarly rely on polyamines to facilitate transcription and translation. Whether polyamines function at additional stages in viral replication remains poorly understood. Picornaviruses, including Coxsackievirus B3 (CVB3), are sensitive to polyamine depletion both in vitro and in vivo; however, precisely how polyamine function in picornavirus infection has not been described. Here, we describe CVB3 mutants that arise with passage in polyamine-depleted conditions. We observe mutations in the 2A and 3C proteases, and we find that these mutant proteases confer resistance to polyamine depletion. Using a split luciferase reporter system to measure protease activity, we determined that polyamines facilitate viral protease activity. We further observe that the 2A and 3C protease mutations enhance reporter protease activity in polyamine-depleted conditions. Finally, we find that these mutations promote cleavage of cellular eIF4G during infection of polyamine-depleted cells. In sum, our results suggest that polyamines are crucial to protease function during picornavirus infection. Further, these data highlight viral proteases as potential antiviral targets and highlight how CVB3 may overcome polyamine-depleting antiviral therapies.
Collapse
Affiliation(s)
- Courtney N Dial
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
- Infectious Disease and Immunology Research Institute, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
| | - Patrick M Tate
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
| | - Thomas M Kicmal
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
- Infectious Disease and Immunology Research Institute, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
| | - Bryan C Mounce
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
- Infectious Disease and Immunology Research Institute, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA.
| |
Collapse
|
14
|
The Origin, Dynamic Morphology, and PI4P-Independent Formation of Encephalomyocarditis Virus Replication Organelles. mBio 2018; 9:mBio.00420-18. [PMID: 29666283 PMCID: PMC5904412 DOI: 10.1128/mbio.00420-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Picornaviruses induce dramatic rearrangements of endomembranes in the cells that they infect to produce dedicated platforms for viral replication. These structures, termed replication organelles (ROs), have been well characterized for the Enterovirus genus of the Picornaviridae However, it is unknown whether the diverse RO morphologies associated with enterovirus infection are conserved among other picornaviruses. Here, we use serial electron tomography at different stages of infection to assess the three-dimensional architecture of ROs induced by encephalomyocarditis virus (EMCV), a member of the Cardiovirus genus of the family of picornaviruses that is distantly related. Ultrastructural analyses revealed connections between early single-membrane EMCV ROs and the endoplasmic reticulum (ER), establishing the ER as a likely donor organelle for their formation. These early single-membrane ROs appear to transform into double-membrane vesicles (DMVs) as infection progresses. Both single- and double-membrane structures were found to support viral RNA synthesis, and progeny viruses accumulated in close proximity, suggesting a spatial association between RNA synthesis and virus assembly. Further, we explored the role of phosphatidylinositol 4-phosphate (PI4P), a critical host factor for both enterovirus and cardiovirus replication that has been recently found to expedite enterovirus RO formation rather than being strictly required. By exploiting an EMCV escape mutant, we found that low-PI4P conditions could also be overcome for the formation of cardiovirus ROs. Collectively, our data show that despite differences in the membrane source, there are striking similarities in the biogenesis, morphology, and transformation of cardiovirus and enterovirus ROs, which may well extend to other picornaviruses.IMPORTANCE Like all positive-sense RNA viruses, picornaviruses induce the rearrangement of host cell membranes to form unique structures, or replication organelles (ROs), that support viral RNA synthesis. Here, we investigate the architecture and biogenesis of cardiovirus ROs and compare them with those induced by enteroviruses, members of the well-characterized picornavirus genus Enterovirus The origins and dynamic morphologies of cardiovirus ROs are revealed using electron tomography, which points to the endoplasmic reticulum as the donor organelle usurped to produce single-membrane tubules and vesicles that transform into double-membrane vesicles. We show that PI4P, a critical lipid for cardiovirus and enterovirus replication, is not strictly required for the formation of cardiovirus ROs, as functional ROs with typical morphologies are formed under phosphatidylinositol 4-kinase type III alpha (PI4KA) inhibition in cells infected with an escape mutant. Our data show that the transformation from single-membrane structures to double-membrane vesicles is a conserved feature of cardiovirus and enterovirus infections that likely extends to other picornavirus genera.
Collapse
|