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Sinha P, Thio CL, Balagopal A. Intracellular Host Restriction of Hepatitis B Virus Replication. Viruses 2024; 16:764. [PMID: 38793645 PMCID: PMC11125714 DOI: 10.3390/v16050764] [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: 04/12/2024] [Revised: 05/06/2024] [Accepted: 05/08/2024] [Indexed: 05/26/2024] Open
Abstract
The hepatitis B virus (HBV) infects hepatocytes and hijacks host cellular mechanisms for its replication. Host proteins can be frontline effectors of the cell's defense and restrict viral replication by impeding multiple steps during its intracellular lifecycle. This review summarizes many of the well-described restriction factors, their mechanisms of restriction, and counteractive measures of HBV, with a special focus on viral transcription. We discuss some of the limitations and knowledge gaps about the restriction factors, highlighting how these factors may be harnessed to facilitate therapeutic strategies against HBV.
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Affiliation(s)
| | | | - Ashwin Balagopal
- Department of Medicine, Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (P.S.); (C.L.T.)
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Gao Y, Feng C, Ma J, Yan Q. Protein arginine methyltransferases (PRMTs): Orchestrators of cancer pathogenesis, immunotherapy dynamics, and drug resistance. Biochem Pharmacol 2024; 221:116048. [PMID: 38346542 DOI: 10.1016/j.bcp.2024.116048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/15/2024] [Accepted: 02/06/2024] [Indexed: 02/16/2024]
Abstract
Protein Arginine Methyltransferases (PRMTs) are a family of enzymes regulating protein arginine methylation, which is a post-translational modification crucial for various cellular processes. Recent studies have highlighted the mechanistic role of PRMTs in cancer pathogenesis, immunotherapy, and drug resistance. PRMTs are involved in diverse oncogenic processes, including cell proliferation, apoptosis, and metastasis. They exert their effects by methylation of histones, transcription factors, and other regulatory proteins, resulting in altered gene expression patterns. PRMT-mediated histone methylation can lead to aberrant chromatin remodeling and epigenetic changes that drive oncogenesis. Additionally, PRMTs can directly interact with key signaling pathways involved in cancer progression, such as the PI3K/Akt and MAPK pathways, thereby modulating cell survival and proliferation. In the context of cancer immunotherapy, PRMTs have emerged as critical regulators of immune responses. They modulate immune checkpoint molecules, including programmed cell death protein 1 (PD-1), through arginine methylation. Drug resistance is a significant challenge in cancer treatment, and PRMTs have been implicated in this phenomenon. PRMTs can contribute to drug resistance through multiple mechanisms, including the epigenetic regulation of drug efflux pumps, altered DNA damage repair, and modulation of cell survival pathways. In conclusion, PRMTs play critical roles in cancer pathogenesis, immunotherapy, and drug resistance. In this overview, we have endeavored to illuminate the mechanistic intricacies of PRMT-mediated processes. Shedding light on these aspects will offer valuable insights into the fundamental biology of cancer and establish PRMTs as promising therapeutic targets.
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Affiliation(s)
- Yihang Gao
- Department of Laboratory Medicine, the Second Hospital of Jilin University, Changchun 130000, China
| | - Chongchong Feng
- Department of Laboratory Medicine, the Second Hospital of Jilin University, Changchun 130000, China.
| | - Jingru Ma
- Department of Laboratory Medicine, the Second Hospital of Jilin University, Changchun 130000, China
| | - Qingzhu Yan
- Department of Ultrasound Medicine, the Second Hospital of Jilin University, Changchun 130000, China
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Zheng K, Chen S, Ren Z, Wang Y. Protein arginine methylation in viral infection and antiviral immunity. Int J Biol Sci 2023; 19:5292-5318. [PMID: 37928266 PMCID: PMC10620831 DOI: 10.7150/ijbs.89498] [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: 08/25/2023] [Accepted: 10/10/2023] [Indexed: 11/07/2023] Open
Abstract
Protein arginine methyltransferase (PRMT)-mediated arginine methylation is an important post-transcriptional modification that regulates various cellular processes including epigenetic gene regulation, genome stability maintenance, RNA metabolism, and stress-responsive signal transduction. The varying substrates and biological functions of arginine methylation in cancer and neurological diseases have been extensively discussed, providing a rationale for targeting PRMTs in clinical applications. An increasing number of studies have demonstrated an interplay between arginine methylation and viral infections. PRMTs have been found to methylate and regulate several host cell proteins and different functional types of viral proteins, such as viral capsids, mRNA exporters, transcription factors, and latency regulators. This modulation affects their activity, subcellular localization, protein-nucleic acid and protein-protein interactions, ultimately impacting their roles in various virus-associated processes. In this review, we discuss the classification, structure, and regulation of PRMTs and their pleiotropic biological functions through the methylation of histones and non-histones. Additionally, we summarize the broad spectrum of PRMT substrates and explore their intricate effects on various viral infection processes and antiviral innate immunity. Thus, comprehending the regulation of arginine methylation provides a critical foundation for understanding the pathogenesis of viral diseases and uncovering opportunities for antiviral therapy.
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Affiliation(s)
- Kai Zheng
- School of Pharmacy, Shenzhen University Medical School, Shenzhen University, Shenzhen, 518055, China
| | - Siyu Chen
- School of Pharmacy, Shenzhen University Medical School, Shenzhen University, Shenzhen, 518055, China
| | - Zhe Ren
- Institute of Biomedicine, College of Life Science and Technology, Guangdong Province Key Laboratory of Bioengineering Medicine, Key Laboratory of Innovative Technology Research on Natural Products and Cosmetics Raw Materials, Jinan University, Guangzhou, 510632, China
| | - Yifei Wang
- Institute of Biomedicine, College of Life Science and Technology, Guangdong Province Key Laboratory of Bioengineering Medicine, Key Laboratory of Innovative Technology Research on Natural Products and Cosmetics Raw Materials, Jinan University, Guangzhou, 510632, China
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Sun H, Tu S, Luo D, Dai C, Jin M, Chen H, Zou J, Zhou H. Protein arginine methyltransferase 5 mediates arginine symmetric dimethylation of influenza A virus PB2 and supports viral replication. J Med Virol 2023; 95:e29171. [PMID: 37830751 DOI: 10.1002/jmv.29171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 09/08/2023] [Accepted: 10/03/2023] [Indexed: 10/14/2023]
Abstract
Influenza A virus (IAV) relies on intricate and highly coordinated associations with host factors for efficient replication and transmission. Characterization of such factors holds great significance for development of anti-IAV drugs. Our study identified protein arginine methyltransferase 5 (PRMT5) as a novel host factor indispensable for IAV replication. Silencing PRMT5 resulted in drastic repression of IAV replication. Our findings revealed that PRMT5 interacts with each protein component of viral ribonucleoproteins (vRNPs) and promotes arginine symmetric dimethylation of polymerase basic 2 (PB2). Overexpression of PRMT5 enhanced viral polymerase activity in a dose-dependent manner, emphasizing its role in genome transcription and replication of IAV. Moreover, analysis of PB2 protein sequences across various subtypes of IAVs demonstrated the high conservation of potential RG motifs recognized by PRMT5. Overall, our study suggests that PRMT5 supports IAV replication by facilitating viral polymerase activity by interacting with PB2 and promoting its arginine symmetric dimethylation. This study deepens our understanding of how IAV manipulates host factors to facilitate its replication and highlights the great potential of PRMT5 to serve as an anti-IAV therapeutic target.
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Affiliation(s)
- Huimin Sun
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Shaoyu Tu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Didan Luo
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Chao Dai
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Meilin Jin
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, Hubei, China
- Hubei Hongshan Laboratory, Wuhan, Hubei, China
| | - Jiahui Zou
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Hongbo Zhou
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, Hubei, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, Hubei, China
- Hubei Hongshan Laboratory, Wuhan, Hubei, China
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Hu X, Chen Z, Wu X, Fu Q, Chen Z, Huang Y, Wu H. PRMT5 Facilitates Infectious Bursal Disease Virus Replication through Arginine Methylation of VP1. J Virol 2023; 97:e0163722. [PMID: 36786602 PMCID: PMC10062139 DOI: 10.1128/jvi.01637-22] [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: 10/18/2022] [Accepted: 01/22/2023] [Indexed: 02/15/2023] Open
Abstract
The infectious bursal diseases virus (IBDV) polymerase, VP1 protein, is responsible for transcription, initial translation and viral genomic replication. Knowledge about the new kind of post-translational modification of VP1 supports identification of novel drugs against the virus. Because the arginine residue is known to be methylated by protein arginine methyltransferase (PRMT) enzyme, we investigated whether IBDV VP1 is a substrate for known PRMTs. In this study, we show that VP1 is specifically associated with and methylated by PRMT5 at the arginine 426 (R426) residue. IBDV infection causes the accumulation of PRMT5 in the cytoplasm, which colocalizes with VP1 as a punctate structure. In addition, ectopic expression of PRMT5 significantly enhances the viral replication. In the presence of PMRT5, enzyme inhibitor and knockout of PRMT5 remarkably decreased viral replication. The polymerase activity of VP1 was severely damaged when R426 mutated to alanine, resulting in impaired viral replication. Our study reports a novel form of post-translational modification of VP1, which supports its polymerase function to facilitate the viral replication. IMPORTANCE Post-translational modification of infectious bursal disease virus (IBDV) VP1 is important for the regulation of its polymerase activity. Investigation of the significance of specific modification of VP1 can lead to better understanding of viral replication and can probably also help in identifying novel targets for antiviral compounds. Our work demonstrates the molecular mechanism of VP1 methylation mediated by PRMT5, which is critical for viral polymerase activity, as well as viral replication. Our study expands a novel insight into the function of arginine methylation of VP1, which might be useful for limiting the replication of IBDV.
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Affiliation(s)
- Xifeng Hu
- Department of Veterinary Preventive Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
| | - Zheng Chen
- Department of Veterinary Preventive Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
| | - Xiangdong Wu
- Department of Veterinary Preventive Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
| | - Qiuling Fu
- Institute of Animal Husbandry and Veterinary Medicine of Fujian Academy of Agricultural Sciences, Fuzhou, People’s Republic of China
| | - Zhen Chen
- Institute of Animal Husbandry and Veterinary Medicine of Fujian Academy of Agricultural Sciences, Fuzhou, People’s Republic of China
| | - Yu Huang
- Institute of Animal Husbandry and Veterinary Medicine of Fujian Academy of Agricultural Sciences, Fuzhou, People’s Republic of China
| | - Huansheng Wu
- Department of Veterinary Preventive Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
- Jiangxi Provincial Key Laboratory for Animal Health, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, People’s Republic of China
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Nakai Y, Miyakawa K, Yamaoka Y, Hatayama Y, Nishi M, Suzuki H, Kimura H, Takahashi H, Kimura Y, Ryo A. Generation and Utilization of a Monoclonal Antibody against Hepatitis B Virus Core Protein for a Comprehensive Interactome Analysis. Microorganisms 2022; 10:microorganisms10122381. [PMID: 36557634 PMCID: PMC9783060 DOI: 10.3390/microorganisms10122381] [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: 10/10/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/05/2022] Open
Abstract
Hepatitis B virus (HBV) core antigen (HBc) is a structural protein that forms the viral nucleocapsid and is involved in various steps of the viral replication cycle, but its role in the pathogenesis of HBV infection is still elusive. In this study, we generated a mouse monoclonal antibody (mAb) against HBc and used it in antibody-based in situ biotinylation analysis in order to identify host proteins that interact with HBc. HBc antigen was produced with a wheat germ cell-free protein synthesis system and used to immunize mice. Among the established hybridoma clones, a single clone (mAb #7) was selected and further characterized for its ability in the antibody-based in situ biotinylation analysis to collect host proteins that are in the vicinity of HBc. Using mass spectrometry, we identified 215 HBc-interacting host proteins, three of which bind HBc most significantly under hypoxic conditions. Our results indicate that mAb #7 can be used to systematically identify host proteins that interact with HBc under pathophysiological conditions, and thus may be useful to explore the molecular pathways involved in HBV-induced cytopathogenesis.
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Affiliation(s)
- Yusuke Nakai
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
- Advanced Medical Research Center, Yokohama City University, Yokohama 236-0004, Japan
| | - Kei Miyakawa
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
| | - Yutaro Yamaoka
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
- Life Science Laboratory, Technology and Development Division, Kanto Chemical Co., Inc., Isehara 259-1146, Japan
| | - Yasuyoshi Hatayama
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
- Advanced Medical Research Center, Yokohama City University, Yokohama 236-0004, Japan
| | - Mayuko Nishi
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
| | - Hidefumi Suzuki
- Department of Molecular Biology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
| | - Hirokazu Kimura
- Department of Health Science, Gunma Paz University Graduate School, Takasaki 370-0006, Japan
| | - Hidehisa Takahashi
- Department of Molecular Biology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
| | - Yayoi Kimura
- Advanced Medical Research Center, Yokohama City University, Yokohama 236-0004, Japan
| | - Akihide Ryo
- Department of Microbiology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
- Advanced Medical Research Center, Yokohama City University, Yokohama 236-0004, Japan
- Correspondence: ; Tel.: +81-45-787-2602
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Prange R. Hepatitis B virus movement through the hepatocyte: An update. Biol Cell 2022; 114:325-348. [PMID: 35984727 DOI: 10.1111/boc.202200060] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/26/2022] [Accepted: 08/12/2022] [Indexed: 11/29/2022]
Abstract
Viruses are obligate intracellular pathogens that utilize cellular machinery for many aspects of their propagation and effective egress of virus particles from host cells is one important determinant of virus infectivity. Hijacking host cell processes applies in particular to the hepatitis B virus (HBV), as its DNA genome with about 3 kb in size is one of the smallest viral genomes known. HBV is a leading cause of liver disease and still displays one of the most successful pathogens in human populations worldwide. The extremely successful spread of this virus is explained by its efficient transmission strategies and its versatile particle types, including virions, empty envelopes, naked capsids and others. HBV exploits distinct host trafficking machineries to assemble and release its particle types including nucleocytoplasmic shuttling transport, secretory and exocytic pathways, the Endosomal Sorting Complexes Required for Transport pathway, and the autophagy pathway. Understanding how HBV uses and subverts host membrane trafficking systems offers the chance of obtaining new mechanistic insights into the regulation and function of this essential cellular processes. It can also help to identify potential targets for antiviral interventions. Here, I will provide an overview of HBV maturation, assembly, and budding, with a focus on recent advances, and will point out areas where questions remain that can benefit from future studies. Unless otherwise indicated, almost all presented knowledge was gained from cell culture-based, HBV in vitro -replication and in vitro -infection systems. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Reinhild Prange
- Department of Virology, University Medical Center of the Johannes Gutenberg University Mainz, Augustusplatz, Mainz, D-55131, Germany
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Conserved Lysine Residues of Hepatitis B Virus Core Protein Are Not Required for Covalently Closed Circular DNA Formation. J Virol 2022; 96:e0071822. [PMID: 35867543 PMCID: PMC9364803 DOI: 10.1128/jvi.00718-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Hepatitis B virus (HBV) core protein (HBc), the building block of the viral capsid, plays a critical role throughout the HBV life cycle. There are two highly conserved lysine residues, namely, K7 and K96, on HBc, which have been proposed to function at various stages of viral replication, potentially through lysine-specific posttranslational modifications (PTMs). Here, we substituted K7 and K96 with alanine or arginine, which would also block potential PTMs on these two lysine residues, and tested the effects of these substitutions on HBV replication and infection. We found that the two lysine residues were dispensable for all intracellular steps of HBV replication. In particular, all mutants were competent to form the covalently closed circular DNA (cccDNA) via the intracellular amplification pathway, indicating that K7 and K96, or any PTMs of these residues, were not essential for nucleocapsid uncoating, a prerequisite for cccDNA formation. Furthermore, we found that K7A and K7R mutations did not affect de novo cccDNA formation and RNA transcription during infection, indicating that K7 or any PTMs of this residue were dispensable for HBV infection. In addition, we demonstrated that the HBc K7 coding sequence (AAA), as part of the HBV polyadenylation signal UAUAAA, was indispensable for viral RNA production, implicating this cis requirement at the RNA level, instead of any function of HBc-K7, likely constrains the identity of the 7th residue of HBc. In conclusion, our results provided novel insights regarding the roles of lysine residues on HBc, and their coding sequences, in the HBV life cycle. IMPORTANCE Hepatitis B virus (HBV) infection remains a public health burden that affects 296 million individuals worldwide. HBV core protein (HBc) is involved in almost all steps in the HBV life cycle. There are two conserved lysine residues on HBc. Here, we found that neither of them is essential for HBV intracellular replication, including the formation of covalently closed circular DNA (cccDNA), the molecular basis for establishing and sustaining the HBV infection. However, K96 is critical for virion morphogenesis, while the K7 coding sequence, but not HBc-K7 itself, is indispensable, as part of the RNA polyadenylation signal, for HBV RNA production from cccDNA. Our results provide novel insights regarding the role of the conserved lysine residues on HBc, and their coding sequences, in viral replication, and should facilitate the development of antiviral drugs against the HBV capsid protein.
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Su PY, Yen SCB, Yang CC, Chang CH, Lin WC, Shih C. Hepatitis B virus virion secretion is a CRM1-spike-mediated late event. J Biomed Sci 2022; 29:44. [PMID: 35729569 PMCID: PMC9210616 DOI: 10.1186/s12929-022-00827-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 06/16/2022] [Indexed: 11/10/2022] Open
Abstract
Background Hepatitis B virus (HBV) is a major human pathogen worldwide. To date, there is no curative treatment for chronic hepatitis B. The mechanism of virion secretion remains to be investigated. Previously, we found that nuclear export of HBc particles can be facilitated via two CRM1-specific nuclear export signals (NES) at the spike tip. Methods In this study, we used site-directed mutagenesis at the CRM1 NES, as well as treatment with CRM1 inhibitors at a low concentration, or CRM1-specific shRNA knockdown, in HBV-producing cell culture, and measured the secretion of various HBV viral and subviral particles via a native agarose gel electrophoresis assay. Separated HBV particles were characterized by Western blot analysis, and their genomic DNA contents were measured by Southern blot analysis. Secreted extracellular particles were compared with intracellular HBc capsids for DNA synthesis and capsid formation. Virion secretion and the in vivo interactions among HBc capsids, CRM1 and microtubules, were examined by proximity ligation assay, immunofluorescence microscopy, and nocodazole treatment. Results We report here that the tip of spike of HBV core (HBc) particles (capsids) contains a complex sensor for secretion of both HBV virions and naked capsids. HBV virion secretion is closely associated with HBc nuclear export in a CRM1-dependent manner. At the conformationally flexible spike tips of HBc particles, NES motifs overlap extensively with motifs important for secretion of HBV virions and naked capsids. Conclusions We provided experimental evidence that virions and naked capsids can egress via two distinct, yet overlapping, pathways. Unlike the secretion of naked capsids, HBV virion secretion is highly CRM1- and microtubule-dependent. CRM1 is well known for its involvement in nuclear transport in literature. To our knowledge, this is the first report that CRM1 is required for virion secretion. CRM1 inhibitors could be a promising therapeutic candidate for chronic HBV patients in clinical medicine. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-022-00827-w.
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Affiliation(s)
- Pei-Yi Su
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, No.100, Shih-Chuan 1st Road, Sanmin, 80708, Kaohsiung, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Shin-Chwen Bruce Yen
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, No.100, Shih-Chuan 1st Road, Sanmin, 80708, Kaohsiung, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Ching-Chun Yang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chih-Hsu Chang
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.,Graduate Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wen-Chang Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chiaho Shih
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, No.100, Shih-Chuan 1st Road, Sanmin, 80708, Kaohsiung, Taiwan. .,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
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10
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Ruml T. The Present and Future of Virology in the Czech Republic-A New Phoenix Made of Ashes? Viruses 2022; 14:v14061303. [PMID: 35746773 PMCID: PMC9231214 DOI: 10.3390/v14061303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 06/10/2022] [Accepted: 06/10/2022] [Indexed: 12/10/2022] Open
Affiliation(s)
- Tomas Ruml
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, 166 28 Prague, Czech Republic
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Srour N, Khan S, Richard S. The Influence of Arginine Methylation in Immunity and Inflammation. J Inflamm Res 2022; 15:2939-2958. [PMID: 35602664 PMCID: PMC9114649 DOI: 10.2147/jir.s364190] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 05/06/2022] [Indexed: 12/24/2022] Open
Abstract
Exploration in the field of epigenetics has revealed that protein arginine methyltransferases (PRMTs) contribute to disease, and this has given way to the development of specific small molecule compounds that inhibit arginine methylation. Protein arginine methylation is known to regulate fundamental cellular processes, such as transcription; pre-mRNA splicing and other RNA processing mechanisms; signal transduction, including the anti-viral response; and cellular metabolism. PRMTs are also implicated in the regulation of physiological processes, including embryonic development, myogenesis, and the immune system. Finally, the dysregulation of PRMTs is apparent in cancer, neurodegeneration, muscular disorders, and during inflammation. Herein, we review the functions of PRMTs in immunity and inflammation. We also discuss recent progress with PRMTs regarding the modulation of gene expression related to T and B lymphocyte differentiation, germinal center dynamics, and anti-viral signaling responses, as well as the clinical relevance of using PRMT inhibitors alone or in combination with other drugs to treat cancer, immune, and inflammatory-related diseases.
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Affiliation(s)
- Nivine Srour
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Sarah Khan
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Stephane Richard
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
- Correspondence: Stephane Richard, Email
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12
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CRM1-spike-mediated nuclear export of hepatitis B virus encapsidated viral RNA. Cell Rep 2022; 38:110472. [PMID: 35263598 DOI: 10.1016/j.celrep.2022.110472] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 01/23/2022] [Accepted: 02/10/2022] [Indexed: 11/20/2022] Open
Abstract
Hepatitis B virus (HBV) is a global pathogen. We report here that the cellular CRM1 machinery can mediate nuclear export of entire HBV core (HBc) particles containing encapsidated viral RNAs. Two CRM1-mediated nuclear export signals (NESCRM1) cluster at the conformationally flexible spike tips of HBc particles. Mutant NESCRM1 capsids exhibit strongly reduced associations with CRM1 and nucleoporin358 in vivo. CRM1 and NXF1 machineries mediate nuclear export of HBc particles independently. Inhibition of nuclear export has pleiotropic consequences, including nuclear accumulation of HBc particles, a significant reduction of encapsidated viral RNAs in the cytoplasm but not in the nucleus, and barely detectable viral DNA. We hypothesize an HBV life cycle where encapsidation of the RNA pregenome can initiate early in the nucleus, whereas DNA genome maturation occurs mainly in the cytoplasm. We identified a druggable target for HBV by blocking its intracellular trafficking.
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13
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Shin HK, Florean O, Hardy B, Doktorova T, Kang MG. Semi-automated approach for generation of biological networks on drug-induced cholestasis, steatosis, hepatitis, and cirrhosis. Toxicol Res 2022; 38:393-407. [PMID: 35865277 PMCID: PMC9247124 DOI: 10.1007/s43188-022-00124-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 02/02/2022] [Accepted: 02/11/2022] [Indexed: 12/03/2022] Open
Abstract
Drug-induced liver injury (DILI) is one of the leading reasons for discontinuation of a new drug development project. Diverse machine learning or deep learning models have been developed to predict DILI. However, these models have not provided an adequate understanding of the mechanisms leading to DILI. The development of safer drugs requires novel computational approaches that enable the prompt understanding of the mechanism of DILI. In this study, the mechanisms leading to the development of cholestasis, steatosis, hepatitis, and cirrhosis were explored using a semi-automated approach for data gathering and associations. Diverse data from ToxCast, Comparative Toxicogenomic Database (CTD), Reactome, and Open TG-GATEs on reference molecules leading to the development of the respective diseases were extracted. The data were used to create biological networks of the four diseases. As expected, the four networks had several common pathways, and a joint DILI network was assembled. Such biological networks could be used in drug discovery to identify possible molecules of concern as they provide a better understanding of the disease-specific key events. The events can be target-tested to provide indications for potential DILI effects.
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Affiliation(s)
- Hyun Kil Shin
- Toxicoinformatics Group, Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114 Republic of Korea
- Human and Environmental Toxicology, University of Science and Technology, Daejeon, 34113 Republic of Korea
| | - Oana Florean
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, 4057 Basel, Switzerland
| | - Barry Hardy
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, 4057 Basel, Switzerland
| | - Tatyana Doktorova
- Edelweiss Connect GmbH, Hochbergerstrasse 60C, 4057 Basel, Switzerland
| | - Myung-Gyun Kang
- Toxicoinformatics Group, Department of Predictive Toxicology, Korea Institute of Toxicology, Daejeon, 34114 Republic of Korea
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14
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Murphy SA, Mapes NJ, Dua D, Kaur B. Histone modifiers at the crossroads of oncolytic and oncogenic viruses. Mol Ther 2022; 30:2153-2162. [PMID: 35143960 DOI: 10.1016/j.ymthe.2022.02.006] [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: 08/27/2021] [Revised: 12/18/2021] [Accepted: 02/04/2022] [Indexed: 02/07/2023] Open
Abstract
Cancer is a disease caused by loss of regulatory processes that control cell cycle, resulting in increased proliferation. The loss of control can deregulate both tumor suppressors and oncogenes. Apart from cell intrinsic gene mutations and environmental factors, infection by cancer-causing viruses also induces changes that lead to malignant transformation. This can be caused by both expression of oncogenic viral proteins and also by changes in cellular genes and proteins that affect the epigenome. Thus, these epigenetic modifiers are good therapeutic targets, and several epigenetic inhibitors are approved for the treatment of different cancers. In addition to small molecule drugs, biological therapies such as antibodies and viral therapies are also increasingly being used to treat cancer. An HSV-1 derived oncolytic virus is currently approved by the US FDA and the European Medicines Agency. Similarly, an adenovirus-based therapeutic is approved for use in China for some cancer types. Since viruses can affect cellular epigenetics, the interaction of epigenome-targeting drugs with oncogenic and oncolytic viruses is a highly significant area of investigation. Here we will review the current knowledge about the impact of using epigenetic drugs in tumors positive for oncogenic viruses or as therapeutic combinations with oncolytic viruses.
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Affiliation(s)
- Sara A Murphy
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030;; University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030
| | - Norman John Mapes
- Center for Biomedical Engineering and Rehabilitation Sciences, Louisiana Tech University, Ruston, LA 71270
| | | | - Balveen Kaur
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030;.
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15
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Lubyova B, Tikalova E, Krulova K, Hodek J, Zabransky A, Hirsch I, Weber J. ATM-Dependent Phosphorylation of Hepatitis B Core Protein in Response to Genotoxic Stress. Viruses 2021; 13:v13122438. [PMID: 34960710 PMCID: PMC8705010 DOI: 10.3390/v13122438] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/29/2021] [Accepted: 12/02/2021] [Indexed: 12/31/2022] Open
Abstract
Chronic hepatitis caused by infection with the Hepatitis B virus is a life-threatening condition. In fact, 1 million people die annually due to liver cirrhosis or hepatocellular carcinoma. Recently, several studies demonstrated a molecular connection between the host DNA damage response (DDR) pathway and HBV replication and reactivation. Here, we investigated the role of Ataxia-telangiectasia-mutated (ATM) and Ataxia telangiectasia and Rad3-related (ATR) PI3-kinases in phosphorylation of the HBV core protein (HBc). We determined that treatment of HBc-expressing hepatocytes with genotoxic agents, e.g., etoposide or hydrogen peroxide, activated the host ATM-Chk2 pathway, as determined by increased phosphorylation of ATM at Ser1981 and Chk2 at Thr68. The activation of ATM led, in turn, to increased phosphorylation of cytoplasmic HBc at serine-glutamine (SQ) motifs located in its C-terminal domain. Conversely, down-regulation of ATM using ATM-specific siRNAs or inhibitor effectively reduced etoposide-induced HBc phosphorylation. Detailed mutation analysis of S-to-A HBc mutants revealed that S170 (S168 in a 183-aa HBc variant) is the primary site targeted by ATM-regulated phosphorylation. Interestingly, mutation of two major phosphorylation sites involving serines at positions 157 and 164 (S155 and S162 in a 183-aa HBc variant) resulted in decreased etoposide-induced phosphorylation, suggesting that the priming phosphorylation at these serine-proline (SP) sites is vital for efficient phosphorylation of SQ motifs. Notably, the mutation of S172 (S170 in a 183-aa HBc variant) had the opposite effect and resulted in massively up-regulated phosphorylation of HBc, particularly at S170. Etoposide treatment of HBV infected HepG2-NTCP cells led to increased levels of secreted HBe antigen and intracellular HBc protein. Together, our studies identified HBc as a substrate for ATM-mediated phosphorylation and mapped the phosphorylation sites. The increased expression of HBc and HBe antigens in response to genotoxic stress supports the idea that the ATM pathway may provide growth advantage to the replicating virus.
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Affiliation(s)
- Barbora Lubyova
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
- Correspondence: (B.L.); (J.W.)
| | - Eva Tikalova
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
| | - Kristyna Krulova
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
| | - Jan Hodek
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
| | - Ales Zabransky
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
| | - Ivan Hirsch
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 252 50 Vestec, Czech Republic
| | - Jan Weber
- IOCB Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, 160 00 Prague, Czech Republic; (E.T.); (K.K.); (J.H.); (A.Z.); (I.H.)
- Correspondence: (B.L.); (J.W.)
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16
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Zábranská H, Zábranský A, Lubyová B, Hodek J, Křenková A, Hubálek M, Weber J, Pichová I. Biogenesis of hepatitis B virus e antigen is driven by translocon-associated protein complex and regulated by conserved cysteine residues within its signal peptide sequence. FEBS J 2021; 289:2895-2914. [PMID: 34839586 PMCID: PMC9300162 DOI: 10.1111/febs.16304] [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] [Received: 06/24/2021] [Revised: 10/27/2021] [Accepted: 11/26/2021] [Indexed: 11/28/2022]
Abstract
Hepatitis B virus uses e antigen (HBe), which is dispensable for virus infectivity, to modulate host immune responses and achieve viral persistence in human hepatocytes. The HBe precursor (p25) is directed to the endoplasmic reticulum (ER), where cleavage of the signal peptide (sp) gives rise to the first processing product, p22. P22 can be retro-translocated back to the cytosol or enter the secretory pathway and undergo a second cleavage event, resulting in secreted p17 (HBe). Here, we report that translocation of p25 to the ER is promoted by translocon-associated protein complex. We have found that p25 is not completely translocated into the ER; a fraction of p25 is phosphorylated and remains in the cytoplasm and nucleus. Within the p25 sp sequence, we have identified three cysteine residues that control the efficiency of sp cleavage and contribute to proper subcellular distribution of the precore pool.
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Affiliation(s)
- Helena Zábranská
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Aleš Zábranský
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Barbora Lubyová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Hodek
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Alena Křenková
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Hubálek
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Weber
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Iva Pichová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
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17
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Kalčic F, Zgarbová M, Hodek J, Chalupský K, Dračínský M, Dvořáková A, Strmeň T, Šebestík J, Baszczyňski O, Weber J, Mertlíková-Kaiserová H, Janeba Z. Discovery of Modified Amidate (ProTide) Prodrugs of Tenofovir with Enhanced Antiviral Properties. J Med Chem 2021; 64:16425-16449. [PMID: 34713696 DOI: 10.1021/acs.jmedchem.1c01444] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This study describes the discovery of novel prodrugs bearing tyrosine derivatives instead of the phenol moiety present in FDA-approved tenofovir alafenamide fumarate (TAF). The synthesis was optimized to afford diastereomeric mixtures of novel prodrugs in one pot (yields up to 86%), and the epimers were resolved using a chiral HPLC column into fast-eluting and slow-eluting epimers. In human lymphocytes, the most efficient tyrosine-based prodrug reached a single-digit picomolar EC50 value against HIV-1 and nearly 300-fold higher selectivity index (SI) compared to TAF. In human hepatocytes, the most efficient prodrugs exhibited subnanomolar EC50 values for HBV and up to 26-fold higher SI compared to TAF. Metabolic studies demonstrated markedly higher cellular uptake of the prodrugs and substantially higher levels of released tenofovir inside the cells compared to TAF. These promising results provide a strong foundation for further evaluation of the reported prodrugs and their potential utility in the development of highly potent antivirals.
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Affiliation(s)
- Filip Kalčic
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic.,Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague 2, Czech Republic
| | - Michala Zgarbová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Jan Hodek
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Karel Chalupský
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Alexandra Dvořáková
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Timotej Strmeň
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Jaroslav Šebestík
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Ondřej Baszczyňski
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic.,Department of Organic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague 2, Czech Republic
| | - Jan Weber
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Helena Mertlíková-Kaiserová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
| | - Zlatko Janeba
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo nám. 2, 160 00 Prague 6, Czech Republic
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18
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Niklasch M, Zimmermann P, Nassal M. The Hepatitis B Virus Nucleocapsid-Dynamic Compartment for Infectious Virus Production and New Antiviral Target. Biomedicines 2021; 9:1577. [PMID: 34829806 PMCID: PMC8615760 DOI: 10.3390/biomedicines9111577] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus (HBV) is a small enveloped DNA virus which replicates its tiny 3.2 kb genome by reverse transcription inside an icosahedral nucleocapsid, formed by a single ~180 amino acid capsid, or core, protein (Cp). HBV causes chronic hepatitis B (CHB), a severe liver disease responsible for nearly a million deaths each year. Most of HBV's only seven primary gene products are multifunctional. Though less obvious than for the multi-domain polymerase, P protein, this is equally crucial for Cp with its multiple roles in the viral life-cycle. Cp provides a stable genome container during extracellular phases, allows for directed intracellular genome transport and timely release from the capsid, and subsequent assembly of new nucleocapsids around P protein and the pregenomic (pg) RNA, forming a distinct compartment for reverse transcription. These opposing features are enabled by dynamic post-transcriptional modifications of Cp which result in dynamic structural alterations. Their perturbation by capsid assembly modulators (CAMs) is a promising new antiviral concept. CAMs inappropriately accelerate assembly and/or distort the capsid shell. We summarize the functional, biochemical, and structural dynamics of Cp, and discuss the therapeutic potential of CAMs based on clinical data. Presently, CAMs appear as a valuable addition but not a substitute for existing therapies. However, as part of rational combination therapies CAMs may bring the ambitious goal of a cure for CHB closer to reality.
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Affiliation(s)
| | | | - Michael Nassal
- Internal Medicine II/Molecular Biology, University Hospital Freiburg, Hugstetter Str. 55, D-79106 Freiburg, Germany; (M.N.); (P.Z.)
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19
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Van Damme E, Vanhove J, Severyn B, Verschueren L, Pauwels F. The Hepatitis B Virus Interactome: A Comprehensive Overview. Front Microbiol 2021; 12:724877. [PMID: 34603251 PMCID: PMC8482013 DOI: 10.3389/fmicb.2021.724877] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/17/2021] [Indexed: 12/19/2022] Open
Abstract
Despite the availability of a prophylactic vaccine, chronic hepatitis B (CHB) caused by the hepatitis B virus (HBV) is a major health problem affecting an estimated 292 million people globally. Current therapeutic goals are to achieve functional cure characterized by HBsAg seroclearance and the absence of HBV-DNA after treatment cessation. However, at present, functional cure is thought to be complicated due to the presence of covalently closed circular DNA (cccDNA) and integrated HBV-DNA. Even if the episomal cccDNA is silenced or eliminated, it remains unclear how important the high level of HBsAg that is expressed from integrated HBV DNA is for the pathology. To identify therapies that could bring about high rates of functional cure, in-depth knowledge of the virus' biology is imperative to pinpoint mechanisms for novel therapeutic targets. The viral proteins and the episomal cccDNA are considered integral for the control and maintenance of the HBV life cycle and through direct interaction with the host proteome they help create the most optimal environment for the virus whilst avoiding immune detection. New HBV-host protein interactions are continuously being identified. Unfortunately, a compendium of the most recent information is lacking and an interactome is unavailable. This article provides a comprehensive review of the virus-host relationship from viral entry to release, as well as an interactome of cccDNA, HBc, and HBx.
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Affiliation(s)
- Ellen Van Damme
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Jolien Vanhove
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium.,Early Discovery Biology, Charles River Laboratories, Beerse, Belgium
| | - Bryan Severyn
- Janssen Research & Development, Janssen Pharmaceutical Companies, Springhouse, PA, United States
| | - Lore Verschueren
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
| | - Frederik Pauwels
- Janssen Research & Development, Janssen Pharmaceutical Companies, Beerse, Belgium
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20
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Jiang Y, Yuan Y, Chen M, Li S, Bai J, Zhang Y, Sun Y, Wang G, Xu H, Wang Z, Zheng Y, Nie H. PRMT5 disruption drives antitumor immunity in cervical cancer by reprogramming T cell-mediated response and regulating PD-L1 expression. Am J Cancer Res 2021; 11:9162-9176. [PMID: 34522232 PMCID: PMC8419032 DOI: 10.7150/thno.59605] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 08/20/2021] [Indexed: 12/31/2022] Open
Abstract
Rationale: Protein arginine methyltransferase 5 (PRMT5) is an oncogene that promotes tumor cell proliferation, invasion and metastasis. However, the underlying mechanisms by which PRMT5 contributes to the progression of cervical cancer and especially the tumor microenvironment remain poorly understood. Methods: PRMT5 expression level was analyzed by Q-PCR, western blot, immunohistochemistry, and TCGA database. The role of PRMT5 in tumor growth was observed by transplanted tumor models, and the function of T cells in tumor microenvironment and in vitro co-culture system was investigated through flow cytometry. The transcriptional regulation of PRMT5 was analyzed using luciferase reporter and chromatin immunoprecipitation (ChIP) assay. The therapeutic effect of PRMT5 inhibitor was evaluated in a cervical cancer cell line transplanted tumor model. Results: We observed that the mRNA and protein expression levels of PRMT5 were increased in cervical cancer tissues, and the high expression of PRMT5 was associated with poor outcomes in cervical cancer patients. The absence of PRMT5 significantly inhibited tumor growth in a cervical cancer transplanted tumor model, and importantly, PRMT5 absence in tumors led to increase the number and enhance the function of tumor infiltrating T cells. Mechanistically, PRMT5 enhanced the transcription of STAT1 through symmetric dimethylation of histone H3R2 and thus promoted PD-L1 expression in cervical cancer cells. Moreover, in an in vitro co-culture system, knockdown of PRMT5 in tumor cells could directly enhance the expression of IFN-γ, TNF-α and granzyme B in T cells. These results suggested that PRMT5 promoted the development of cervical cancer by the crosstalk between tumor cells and T cells. Furthermore, the PRMT5 inhibitor EPZ015666 treatment could suppress tumor growth in a cervical cancer transplanted tumor model. Conclusion: Our results clarify a new mechanism which PRMT5 knockdown in cervical cancer cells drives an antitumor function via reprogramming T cell-mediated response and regulating PD-L1 expression. Thus, our study highlights that PRMT5 may be a potential target for cervical cancer therapy.
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21
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Liang Z, Wen C, Jiang H, Ma S, Liu X. Protein Arginine Methyltransferase 5 Functions via Interacting Proteins. Front Cell Dev Biol 2021; 9:725301. [PMID: 34513846 PMCID: PMC8432624 DOI: 10.3389/fcell.2021.725301] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/04/2021] [Indexed: 12/25/2022] Open
Abstract
The protein arginine methyltransferases (PRMTs) are involved in such biological processes as transcription regulation, DNA repair, RNA splicing, and signal transduction, etc. In this study, we mainly focused on PRMT5, a member of the type II PRMTs, which functions mainly alongside other interacting proteins. PRMT5 has been shown to be overexpressed in a wide variety of cancers and other diseases, and is involved in the regulation of Epstein-Barr virus infection, viral carcinogenesis, spliceosome, hepatitis B, cell cycles, and various signaling pathways. We analyzed the regulatory roles of PRMT5 and interacting proteins in various biological processes above-mentioned, to elucidate for the first time the interaction between PRMT5 and its interacting proteins. This systemic analysis will enrich the biological theory and contribute to the development of novel therapies.
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Affiliation(s)
- Zhenzhen Liang
- School of Public Health and Management, Wenzhou Medical University, Wenzhou, China.,NHC Key Lab of Radiobiology, Jilin University, Changchun, China
| | - Chaowei Wen
- School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Heya Jiang
- School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Shumei Ma
- School of Public Health and Management, Wenzhou Medical University, Wenzhou, China
| | - Xiaodong Liu
- School of Public Health and Management, Wenzhou Medical University, Wenzhou, China.,Key Laboratory of Watershed Science and Health of Zhejiang Province, Wenzhou Medical University, Wenzhou, China
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22
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Protein arginine methylation: from enigmatic functions to therapeutic targeting. Nat Rev Drug Discov 2021; 20:509-530. [PMID: 33742187 DOI: 10.1038/s41573-021-00159-8] [Citation(s) in RCA: 175] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/02/2021] [Indexed: 02/06/2023]
Abstract
Protein arginine methyltransferases (PRMTs) are emerging as attractive therapeutic targets. PRMTs regulate transcription, splicing, RNA biology, the DNA damage response and cell metabolism; these fundamental processes are altered in many diseases. Mechanistically understanding how these enzymes fuel and sustain cancer cells, especially in specific metabolic contexts or in the presence of certain mutations, has provided the rationale for targeting them in oncology. Ongoing inhibitor development, facilitated by structural biology, has generated tool compounds for the majority of PRMTs and enabled clinical programmes for the most advanced oncology targets, PRMT1 and PRMT5. In-depth mechanistic investigations using genetic and chemical tools continue to delineate the roles of PRMTs in regulating immune cells and cancer cells, and cardiovascular and neuronal function, and determine which pathways involving PRMTs could be synergistically targeted in combination therapies for cancer. This research is enhancing our knowledge of the complex functions of arginine methylation, will guide future clinical development and could identify new clinical indications.
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23
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Cai T, Yu Z, Wang Z, Liang C, Richard S. Arginine methylation of SARS-Cov-2 nucleocapsid protein regulates RNA binding, its ability to suppress stress granule formation, and viral replication. J Biol Chem 2021; 297:100821. [PMID: 34029587 PMCID: PMC8141346 DOI: 10.1016/j.jbc.2021.100821] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/13/2021] [Accepted: 05/20/2021] [Indexed: 12/18/2022] Open
Abstract
Viral proteins are known to be methylated by host protein arginine methyltransferases (PRMTs) necessary for the viral life cycle, but it remains unknown whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proteins are methylated. Herein, we show that PRMT1 methylates SARS-CoV-2 nucleocapsid (N) protein at residues R95 and R177 within RGG/RG motifs, preferred PRMT target sequences. We confirmed arginine methylation of N protein by immunoblotting viral proteins extracted from SARS-CoV-2 virions isolated from cell culture. Type I PRMT inhibitor (MS023) or substitution of R95 or R177 with lysine inhibited interaction of N protein with the 5'-UTR of SARS-CoV-2 genomic RNA, a property required for viral packaging. We also defined the N protein interactome in HEK293 cells, which identified PRMT1 and many of its RGG/RG substrates, including the known interacting protein G3BP1 as well as other components of stress granules (SGs), which are part of the host antiviral response. Methylation of R95 regulated the ability of N protein to suppress the formation of SGs, as R95K substitution or MS023 treatment blocked N-mediated suppression of SGs. Also, the coexpression of methylarginine reader Tudor domain-containing protein 3 quenched N protein-mediated suppression of SGs in a dose-dependent manner. Finally, pretreatment of VeroE6 cells with MS023 significantly reduced SARS-CoV-2 replication. Because type I PRMT inhibitors are already undergoing clinical trials for cancer treatment, inhibiting arginine methylation to target the later stages of the viral life cycle such as viral genome packaging and assembly of virions may represent an additional therapeutic application of these drugs.
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Affiliation(s)
- Ting Cai
- Segal Cancer Center, Lady Davis Institute for Medical Research and Gerald Bronfman Department of Oncology and Departments of Biochemistry, Human Genetics and Medicine, McGill University, Montréal, Québec, Canada
| | - Zhenbao Yu
- Segal Cancer Center, Lady Davis Institute for Medical Research and Gerald Bronfman Department of Oncology and Departments of Biochemistry, Human Genetics and Medicine, McGill University, Montréal, Québec, Canada
| | - Zhen Wang
- McGill Centre for Viral Diseases, Lady Davis Institute for Medical Research and Department of Medicine, Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada
| | - Chen Liang
- McGill Centre for Viral Diseases, Lady Davis Institute for Medical Research and Department of Medicine, Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada
| | - Stéphane Richard
- Segal Cancer Center, Lady Davis Institute for Medical Research and Gerald Bronfman Department of Oncology and Departments of Biochemistry, Human Genetics and Medicine, McGill University, Montréal, Québec, Canada.
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24
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Abstract
Arginine methylation is an essential post-translational modification (PTM) deposited by protein arginine methyltransferases (PRMTs) and recognized by Tudor domain-containing proteins. Of the nine mammalian PRMTs, PRMT5 is the primary enzyme responsible for the deposition of symmetric arginine methylation marks in cells. The staphylococcal nuclease and Tudor domain-containing 1 (SND1) effector protein is a key reader of the marks deposited by PRMT5. Both PRMT5 and SND1 are broadly expressed and their deregulation is reported to be associated with a range of disease phenotypes, including cancer. Hepatocellular carcinoma (HCC) is an example of a cancer type that often displays elevated PRMT5 and SND1 levels, and there is evidence that hyperactivation of this axis is oncogenic. Importantly, this pathway can be tempered with small-molecule inhibitors that target PRMT5, offering a therapeutic node for cancer, such as HCC, that display high PRMT5–SND1 axis activity. Here we summarize the known activities of this writer–reader pair, with a focus on their biological roles in HCC. This will help establish a foundation for treating HCC with PRMT5 inhibitors and also identify potential biomarkers that could predict sensitivity to this type of therapy.
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Affiliation(s)
- Tanner Wright
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA; (T.W.); (Y.W.)
- Graduate Program in Genetics & Epigenetics, UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Yalong Wang
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA; (T.W.); (Y.W.)
| | - Mark T. Bedford
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Smithville, TX 78957, USA; (T.W.); (Y.W.)
- Correspondence:
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Hepatitis B Core Protein Is Post-Translationally Modified through K29-Linked Ubiquitination. Cells 2020; 9:cells9122547. [PMID: 33256078 PMCID: PMC7760836 DOI: 10.3390/cells9122547] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/19/2020] [Accepted: 11/24/2020] [Indexed: 12/28/2022] Open
Abstract
Hepatitis B virus (HBV) core protein (HBc) plays many roles in the HBV life cycle, such as regulation of transcription, RNA encapsidation, reverse transcription, and viral release. To accomplish these functions, HBc interacts with many host proteins and undergoes different post-translational modifications (PTMs). One of the most common PTMs is ubiquitination, which was shown to change the function, stability, and intracellular localization of different viral proteins, but the role of HBc ubiquitination in the HBV life cycle remains unknown. Here, we found that HBc protein is post-translationally modified through K29-linked ubiquitination. We performed a series of co-immunoprecipitation experiments with wild-type HBc, lysine to arginine HBc mutants and wild-type ubiquitin, single lysine to arginine ubiquitin mutants, or single ubiquitin-accepting lysine constructs. We observed that HBc protein could be modified by ubiquitination in transfected as well as infected hepatoma cells. In addition, ubiquitination predominantly occurred on HBc lysine 7 and the preferred ubiquitin chain linkage was through ubiquitin-K29. Mass spectrometry (MS) analyses detected ubiquitin protein ligase E3 component N-recognin 5 (UBR5) as a potential E3 ubiquitin ligase involved in K29-linked ubiquitination. These findings emphasize that ubiquitination of HBc may play an important role in HBV life cycle.
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Zhang BY, Chai DP, Wu YH, Qiu LP, Zhang YY, Ye ZH, Yu XP. Potential Drug Targets Against Hepatitis B Virus Based on Both Virus and Host Factors. Curr Drug Targets 2020; 20:1636-1651. [PMID: 31362671 DOI: 10.2174/1389450120666190729115646] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/24/2019] [Accepted: 06/28/2019] [Indexed: 12/17/2022]
Abstract
BACKGROUND Hepatitis B is a very harmful and epidemic disease caused by hepatitis B virus (HBV). Although an effective anti-HBV vaccine is available, chronic infection poses still a huge health burden in the whole world. The present anti-HBV drugs including nucleoside analogues and interferonalpha have their limitations without exception. There is no effective drug and therapeutic method that can really and truly cure hepatitis B so far. The variability of HBV genome results in that a significant number of patients develop drug resistance during the long-term use of anti-HBV drugs. Hence, it is urgently needed to discover novel targets and develop new drugs against hepatitis B. OBJECTIVE The review aims to provide the theory support for designing of the anti-HBV innovative drugs by offering a summary of the current situation of antiviral potential targets. RESULTS AND CONCLUSION Since HBV is obligate intracellular parasite, and as such it depends on host cellular components and functions to replicate itself. The targeting both virus and host might be a novel therapeutic option for hepatitis B. Accordingly, we analyse the advances in the study of the potential drug targets for anti-HBV infection, focusing on targeting virus genome, on targeting host cellular functions and on targeting virus-host proteins interactions, respectively. Meanwhile, the immune targets against chronic hepatitis B are also emphasized. In short, the review provides a summary of antiviral therapeutic strategies to target virus factors, host factors and immune factors for future designing of the innovative drug against HBV infection.
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Affiliation(s)
- Bing-Yi Zhang
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Dan-Ping Chai
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Yi-Hang Wu
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Li-Peng Qiu
- Institute of Life Sciences, Jiangsu University, Zhenjiang 212013, China
| | - Yong-Yong Zhang
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Zi-Hong Ye
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Xiao-Ping Yu
- Department of Pharmacy, Zhejiang Provincial Key Laboratory of Biometrology and Inspection & Quarantine, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
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27
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Engineered Fragments of the PSMA-Specific 5D3 Antibody and Their Functional Characterization. Int J Mol Sci 2020; 21:ijms21186672. [PMID: 32932591 PMCID: PMC7555429 DOI: 10.3390/ijms21186672] [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] [Received: 08/18/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 11/29/2022] Open
Abstract
Prostate-Specific Membrane Antigen (PSMA) is an established biomarker for the imaging and experimental therapy of prostate cancer (PCa), as it is strongly upregulated in high-grade primary, androgen-independent, and metastatic lesions. Here, we report on the development and functional characterization of recombinant single-chain Fv (scFv) and Fab fragments derived from the 5D3 PSMA-specific monoclonal antibody (mAb). These fragments were engineered, heterologously expressed in insect S2 cells, and purified to homogeneity with yields up to 20 mg/L. In vitro assays including ELISA, immunofluorescence and flow cytometry, revealed that the fragments retain the nanomolar affinity and single target specificity of the parent 5D3 antibody. Importantly, using a murine xenograft model of PCa, we verified the suitability of fluorescently labeled fragments for in vivo imaging of PSMA-positive tumors and compared their pharmacokinetics and tissue distribution to the parent mAb. Collectively, our data provide an experimental basis for the further development of 5D3 recombinant fragments for future clinical use.
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Janovec V, Hodek J, Clarova K, Hofman T, Dostalik P, Fronek J, Chlupac J, Chaperot L, Durand S, Baumert TF, Pichova I, Lubyova B, Hirsch I, Weber J. Toll-like receptor dual-acting agonists are potent inducers of PBMC-produced cytokines that inhibit hepatitis B virus production in primary human hepatocytes. Sci Rep 2020; 10:12767. [PMID: 32728070 PMCID: PMC7392756 DOI: 10.1038/s41598-020-69614-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 07/09/2020] [Indexed: 02/06/2023] Open
Abstract
Recombinant interferon-α (IFN-α) treatment functionally cures chronic hepatitis B virus (HBV) infection in some individuals and suppresses virus replication in hepatocytes infected in vitro. We studied the antiviral effect of conditioned media (CM) from peripheral blood mononuclear cells (PBMCs) stimulated with agonists of Toll-like receptors (TLRs) 2, 7, 8 and 9. We found that CM from PBMCs stimulated with dual-acting TLR7/8 (R848) and TLR2/7 (CL413) agonists were more potent drivers of inhibition of HBe and HBs antigen secretion from HBV-infected primary human hepatocytes (PHH) than CM from PBMCs stimulated with single-acting TLR7 (CL264) or TLR9 (CpG-B) agonists. Inhibition of HBV in PHH did not correlate with the quantity of PBMC-produced IFN-α, but it was a complex function of multiple secreted cytokines. More importantly, we found that the CM that efficiently inhibited HBV production in freshly isolated PHH via various cytokine repertoires and mechanisms did not reduce covalently closed circular (ccc)DNA levels. We confirmed our data with a cell culture model based on HepG2-NTCP cells and the plasmacytoid dendritic cell line GEN2.2. Collectively, our data show the importance of dual-acting TLR agonists inducing broad cytokine repertoires. The development of poly-specific TLR agonists provides novel opportunities towards functional HBV cure.
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Affiliation(s)
- Vaclav Janovec
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150, Vestec, Czech Republic.,IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Jan Hodek
- IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Kamila Clarova
- IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Tomas Hofman
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150, Vestec, Czech Republic.,IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Pavel Dostalik
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150, Vestec, Czech Republic
| | - Jiri Fronek
- Transplantation Surgery Department, Institute for Clinical and Experimental Medicine, 14021, Prague, Czech Republic.,Department of Anatomy, Second Faculty of Medicine, Charles University, 15006, Prague, Czech Republic
| | - Jaroslav Chlupac
- Transplantation Surgery Department, Institute for Clinical and Experimental Medicine, 14021, Prague, Czech Republic.,Department of Anatomy, Second Faculty of Medicine, Charles University, 15006, Prague, Czech Republic
| | - Laurence Chaperot
- CNRS UMR5309, Inserm U1209, CHU Grenoble Alpes, IAB, EFS, Université Grenoble Alpes, 38000, Grenoble, France
| | - Sarah Durand
- Inserm, Institut de Recherche Sur Les Maladies Virales Et Hepatiques UMRS 1110, Universite de Strasbourg, 67000, Strasbourg, France
| | - Thomas F Baumert
- Inserm, Institut de Recherche Sur Les Maladies Virales Et Hepatiques UMRS 1110, Universite de Strasbourg, 67000, Strasbourg, France.,Pole Hepato-Digestif, Institut Hospitalo-Universitaire, Hopitaux Universitaires de Strasbourg, 67000, Strasbourg, France
| | - Iva Pichova
- IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Barbora Lubyova
- IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic
| | - Ivan Hirsch
- Department of Genetics and Microbiology, Faculty of Science, Charles University, BIOCEV, 25150, Vestec, Czech Republic. .,IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic. .,Institute of Molecular Genetics of the Czech Academy of Sciences, 14220, Prague, Czech Republic.
| | - Jan Weber
- IOCB & Gilead Research Center, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Science, 16610, Prague, Czech Republic.
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Assi W, Hirose T, Wada S, Matsuura R, Takeshima SN, Aida Y. PRMT5 Is Required for Bovine Leukemia Virus Infection In Vivo and Regulates BLV Gene Expression, Syncytium Formation, and Glycosylation In Vitro. Viruses 2020; 12:E650. [PMID: 32560231 PMCID: PMC7354529 DOI: 10.3390/v12060650] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/12/2020] [Accepted: 06/13/2020] [Indexed: 02/07/2023] Open
Abstract
Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leukosis, which is the most common neoplastic disease of cattle and is closely related to human T-cell leukemia viruses. We investigated the role of a new host protein, PRMT5, in BLV infection. We found that PRMT5 is overexpressed only in BLV-infected cattle with a high proviral load, but not in those with a low proviral load. Furthermore, this upregulation continued to the lymphoma stage. PRMT5 expression was upregulated in response to experimental BLV infection; moreover, PRMT5 upregulation began in an early stage of BLV infection rather than after a long period of proviral latency. Second, siRNA-mediated PRMT5 knockdown enhanced BLV gene expression at the transcript and protein levels. Additionally, a selective small-molecule inhibitor of PRMT5 (CMP5) enhanced BLV gene expression. Interestingly, CMP5 treatment, but not siRNA knockdown, altered the gp51 glycosylation pattern and increased the molecular weight of gp51, thereby decreasing BLV-induced syncytium formation. This was supported by the observation that CMP5 treatment enhanced the formation of the complex type of N-glycan more than the high mannose type. In conclusion, PRMT5 overexpression is related to the development of BLV infection with a high proviral load and lymphoma stage and PRMT5 inhibition enhances BLV gene expression. This is the first study to investigate the role of PRMT5 in BLV infection in vivo and in vitro and to reveal a novel function for a small-molecule compound in BLV-gp51 glycosylation processing.
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Affiliation(s)
- Wlaa Assi
- Laboratory of Viral Infectious Diseases, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (W.A.); (T.H.); (R.M.); (S.-n.T.)
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan;
| | - Tomoya Hirose
- Laboratory of Viral Infectious Diseases, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (W.A.); (T.H.); (R.M.); (S.-n.T.)
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Satoshi Wada
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan;
| | - Ryosuke Matsuura
- Laboratory of Viral Infectious Diseases, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (W.A.); (T.H.); (R.M.); (S.-n.T.)
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Shin-nosuke Takeshima
- Laboratory of Viral Infectious Diseases, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (W.A.); (T.H.); (R.M.); (S.-n.T.)
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Photonics Control Technology Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan;
- Department of Food and Nutrition, Jumonji University, Niiza, Saitama 352-8510, Japan
| | - Yoko Aida
- Laboratory of Viral Infectious Diseases, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; (W.A.); (T.H.); (R.M.); (S.-n.T.)
- Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
- Nakamura Laboratory, Baton Zone program, Riken Cluster for Science, Technology and Innovation Hub, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Abstract
Antiviral drugs have traditionally been developed by directly targeting essential viral components. However, this strategy often fails due to the rapid generation of drug-resistant viruses. Recent genome-wide approaches, such as those employing small interfering RNA (siRNA) or clustered regularly interspaced short palindromic repeats (CRISPR) or those using small molecule chemical inhibitors targeting the cellular "kinome," have been used successfully to identify cellular factors that can support virus replication. Since some of these cellular factors are critical for virus replication, but are dispensable for the host, they can serve as novel targets for antiviral drug development. In addition, potentiation of immune responses, regulation of cytokine storms, and modulation of epigenetic changes upon virus infections are also feasible approaches to control infections. Because it is less likely that viruses will mutate to replace missing cellular functions, the chance of generating drug-resistant mutants with host-targeted inhibitor approaches is minimized. However, drug resistance against some host-directed agents can, in fact, occur under certain circumstances, such as long-term selection pressure of a host-directed antiviral agent that can allow the virus the opportunity to adapt to use an alternate host factor or to alter its affinity toward the target that confers resistance. This review describes novel approaches for antiviral drug development with a focus on host-directed therapies and the potential mechanisms that may account for the acquisition of antiviral drug resistance against host-directed agents.
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31
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Expression of quasi-equivalence and capsid dimorphism in the Hepadnaviridae. PLoS Comput Biol 2020; 16:e1007782. [PMID: 32310951 PMCID: PMC7192502 DOI: 10.1371/journal.pcbi.1007782] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 04/30/2020] [Accepted: 03/10/2020] [Indexed: 12/13/2022] Open
Abstract
Hepatitis B virus (HBV) is a leading cause of liver disease. The capsid is an essential component of the virion and it is therefore of interest how it assembles and disassembles. The capsid protein is unusual both for its rare fold and that it polymerizes according to two different icosahedral symmetries, causing the polypeptide chain to exist in seven quasi-equivalent environments: A, B, and C in AB and CC dimers in T = 3 capsids, and A, B, C, and D in AB and CD dimers in T = 4 capsids. We have compared the two capsids by cryo-EM at 3.5 Å resolution. To ensure a valid comparison, the two capsids were prepared and imaged under identical conditions. We find that the chains have different conformations and potential energies, with the T = 3 C chain having the lowest. Three of the four quasi-equivalent dimers are asymmetric with respect to conformation and potential energy; however, the T = 3 CC dimer is symmetrical and has the lowest potential energy although its intra-dimer interface has the least free energy of formation. Of all the inter-dimer interfaces, the CB interface has the least area and free energy, in both capsids. From the calculated energies of higher-order groupings of dimers discernible in the lattices we predict early assembly intermediates, and indeed we observe such structures by negative stain EM of in vitro assembly reactions. By sequence analysis and computational alanine scanning we identify key residues and motifs involved in capsid assembly. Our results explain several previously reported observations on capsid assembly, disassembly, and dimorphism. Hepatitis B virus has infected approximately one third of the human population and causes almost 1 million deaths from liver disease annually. The capsid is a defining feature of a virus, distinct from host components, and therefore a target for intervention. Unusually for a virus, Hepatitis B assembles two capsids, with different geometries, from the same dimeric protein. Geometric principles dictate that the subunits in this system occupy seven different environments. From comparing the two capsids by cryo-electron microscopy at high resolution under the exact same conditions we find that the polypeptide chains adopt seven different conformations. We use these structures to calculate potential energies (analogous to elastic deformation or strain) for the individual chains, dimers, and several higher-order groupings discernible in the two lattices. We also calculate the binding energies between chains. We find that some groupings have substantially lower energy and are therefore potentially more stable, allowing us to predict likely intermediates on the two assembly pathways. We also observe such intermediates by electron microscopy of in vitro capsid assembly reactions. This is the first structural characterization of the early assembly intermediates of this important human pathogen.
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Mao B, Wang Z, Pi S, Long Q, Chen K, Cui J, Huang A, Hu Y. Difluoromethylornithine, a Decarboxylase 1 Inhibitor, Suppresses Hepatitis B Virus Replication by Reducing HBc Protein Levels. Front Cell Infect Microbiol 2020; 10:158. [PMID: 32373551 PMCID: PMC7176913 DOI: 10.3389/fcimb.2020.00158] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 03/24/2020] [Indexed: 12/13/2022] Open
Abstract
Current treatments of hepatitis B virus (HBV) are limited to Interferon-alpha or the nucleos(t)ide analogs antiviral therapies, and it is crucial to develop and define new antiviral drugs to cure HBV. In this study, we explored the anti-HBV effect of difluoromethylornithine (DFMO), an irreversibly inhibitor of decarboxylase 1(ODC1) on HBV replication. Firstly, we found that polyamines contributed to HBV DNA replication via increasing levels of the HBV core protein (HBc) and capsids. In contrast, depletion of polyamines either by silencing the expression of ODC1 or DFMO treatment, resulted in decreasing viral DNA replication and levels of HBc protein and capsids. Furthermore, we found that DFMO decreased the stability of the HBc protein without affecting mRNA transcription and protein translation. Taken together, our findings demonstrate that DFMO inhibits HBV replication by reducing HBc stability and this may provide a new approach for HBV therapeutics.
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Affiliation(s)
- Binli Mao
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Zhuo Wang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Sidie Pi
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Quanxin Long
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Ke Chen
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Jing Cui
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Ailong Huang
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - Yuan Hu
- Key Laboratory of Molecular Biology on Infectious Diseases, Ministry of Education, Institute for Viral Hepatitis, Department of Infectious Diseases, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
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Persistence of Hepatitis B Virus DNA and the Tempos between Virion Secretion and Genome Maturation in a Mouse Model. J Virol 2019; 93:JVI.01001-19. [PMID: 31462567 PMCID: PMC6819939 DOI: 10.1128/jvi.01001-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 08/23/2019] [Indexed: 12/19/2022] Open
Abstract
Chronic infection with human hepatitis B virus (HBV) could lead to cirrhosis and hepatoma. At present, there is no effective treatment to eradicate the virus from patients. HBV in chronic carriers does not exist as a single homogeneous population. The most frequent naturally occurring mutation in HBV core protein occurs at amino acid 97, changing an isoleucine to leucine (I97L). One dogma in the field is that only virions containing a mature genome are preferentially secreted into the medium. Here, we demonstrated that mutant I97L can secrete immature genome in mice. Although viral DNA of mutant I97L with immature genome is less persistent than wild-type HBV in time course experiments, viral DNA of mutant P130T with genome hypermaturation, surprisingly, is more persistent. Therefore, virion secretion regulated by genome maturity could influence viral persistence. It remains an open issue whether virion secretion could be a drug target for HBV therapy. Hepatitis B virus (HBV) core protein (HBc) accumulates frequent mutations in natural infection. Wild-type HBV is known to secrete predominantly virions containing mature DNA genome. However, a frequent naturally occurring HBc variant, I97L, changing from an isoleucine to a leucine at amino acid 97, exhibited an immature secretion phenotype in culture, which preferentially secretes virions containing immature genomes. In contrast, mutant P130T, changing from a proline to a threonine at amino acid 130, exhibited a hypermaturation phenotype by accumulating an excessive amount of intracellular fully mature DNA genome. Using a hydrodynamic delivery mouse model, we studied the in vivo behaviors of these two mutants, I97L and P130T. We detected no naked core particles in all hydrodynamically injected mice. Mutant I97L in mice exhibited pleiotropic phenotypes: (i) excessive numbers of serum HBV virions containing immature genomes, (ii) significantly reduced numbers of intracellular relaxed-circle and single-stranded DNAs, and (iii) less persistent intrahepatic and secreted HBV DNAs than wild-type HBV. These pleiotropic phenotypes were observed in both immunocompetent and immunodeficient mice. Although mutant P130T also displayed a hypermaturation phenotype in vivo, it cannot efficiently rescue the immature virion secretion of mutant I97L. Unexpectedly, the single mutant P130T exhibited in vivo a novel phenotype in prolonging the persistence of HBV genome in hepatocytes. Taken together, our studies provide a plausible rationale for HBV to regulate envelopment morphogenesis and virion secretion via genome maturity, which is likely to play an important role in the persistence of viral DNA in this mouse model. IMPORTANCE Chronic infection with human hepatitis B virus (HBV) could lead to cirrhosis and hepatoma. At present, there is no effective treatment to eradicate the virus from patients. HBV in chronic carriers does not exist as a single homogeneous population. The most frequent naturally occurring mutation in HBV core protein occurs at amino acid 97, changing an isoleucine to leucine (I97L). One dogma in the field is that only virions containing a mature genome are preferentially secreted into the medium. Here, we demonstrated that mutant I97L can secrete immature genome in mice. Although viral DNA of mutant I97L with immature genome is less persistent than wild-type HBV in time course experiments, viral DNA of mutant P130T with genome hypermaturation, surprisingly, is more persistent. Therefore, virion secretion regulated by genome maturity could influence viral persistence. It remains an open issue whether virion secretion could be a drug target for HBV therapy.
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34
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Mohd-Ismail NK, Lim Z, Gunaratne J, Tan YJ. Mapping the Interactions of HBV cccDNA with Host Factors. Int J Mol Sci 2019; 20:ijms20174276. [PMID: 31480501 PMCID: PMC6747236 DOI: 10.3390/ijms20174276] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 02/06/2023] Open
Abstract
Hepatitis B virus (HBV) infection is a major health problem affecting about 300 million people globally. Although successful administration of a prophylactic vaccine has reduced new infections, a cure for chronic hepatitis B (CHB) is still unavailable. Current anti-HBV therapies slow down disease progression but are not curative as they cannot eliminate or permanently silence HBV covalently closed circular DNA (cccDNA). The cccDNA minichromosome persists in the nuclei of infected hepatocytes where it forms the template for all viral transcription. Interactions between host factors and cccDNA are crucial for its formation, stability, and transcriptional activity. Here, we summarize the reported interactions between HBV cccDNA and various host factors and their implications on HBV replication. While the virus hijacks certain cellular processes to complete its life cycle, there are also host factors that restrict HBV infection. Therefore, we review both positive and negative regulation of HBV cccDNA by host factors and the use of small molecule drugs or sequence-specific nucleases to target these interactions or cccDNA directly. We also discuss several reporter-based surrogate systems that mimic cccDNA biology which can be used for drug library screening of cccDNA-targeting compounds as well as identification of cccDNA-related targets.
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Affiliation(s)
- Nur K Mohd-Ismail
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore 117545, Singapore
| | - Zijie Lim
- Department of Medicine, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore 119228, Singapore
| | - Jayantha Gunaratne
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore
| | - Yee-Joo Tan
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University Health System (NUHS), National University of Singapore, Singapore 117545, Singapore.
- Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore 138673, Singapore.
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Dilworth D, Barsyte-Lovejoy D. Targeting protein methylation: from chemical tools to precision medicines. Cell Mol Life Sci 2019; 76:2967-2985. [PMID: 31104094 PMCID: PMC11105543 DOI: 10.1007/s00018-019-03147-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 05/10/2019] [Indexed: 12/15/2022]
Abstract
The methylation of proteins is integral to the execution of many important biological functions, including cell signalling and transcriptional regulation. Protein methyltransferases (PMTs) are a large class of enzymes that carry out the addition of methyl marks to a broad range of substrates. PMTs are critical for normal cellular physiology and their dysregulation is frequently observed in human disease. As such, PMTs have emerged as promising therapeutic targets with several inhibitors now in clinical trials for oncology indications. The discovery of chemical inhibitors and antagonists of protein methylation signalling has also profoundly impacted our general understanding of PMT biology and pharmacology. In this review, we present general principles for drugging protein methyltransferases or their downstream effectors containing methyl-binding modules, as well as best-in-class examples of the compounds discovered and their impact both at the bench and in the clinic.
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Affiliation(s)
- David Dilworth
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7, Canada
| | - Dalia Barsyte-Lovejoy
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7, Canada.
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Hu J, Cheng J, Tang L, Hu Z, Luo Y, Li Y, Zhou T, Chang J, Guo JT. Virological Basis for the Cure of Chronic Hepatitis B. ACS Infect Dis 2019; 5:659-674. [PMID: 29893548 DOI: 10.1021/acsinfecdis.8b00081] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hepatitis B virus (HBV) has infected one-third of world population, and 240 million people are chronic carriers, to whom a curative therapy is still not available. Similar to other viruses, persistent HBV infection relies on the virus to exploit host cell functions to support its replication and efficiently evade host innate and adaptive antiviral immunity. Understanding HBV replication and concomitant host cell interactions is thus instrumental for development of therapeutics to disrupt the virus-host interactions critical for its persistence and cure chronic hepatitis B. Although the currently available cell culture systems of HBV infection are refractory to genome-wide high throughput screening of key host cellular factors essential for and/or regulating HBV replication, classic one-gene (or pathway)-at-a-time studies in the last several decades have already revealed many aspects of HBV-host interactions. An overview of the landscape of HBV-hepatocyte interaction indicates that, in addition to more tightly suppressing viral replication by directly targeting viral proteins, disruption of key viral-host cell interactions to eliminate or inactivate the covalently closed circular (ccc) DNA, the most stable HBV replication intermediate that exists as an episomal minichromosome in the nucleus of infected hepatocyte, is essential to achieve a functional cure of chronic hepatitis B. Moreover, therapeutic targeting of integrated HBV DNA and their transcripts may also be required to induce hepatitis B virus surface antigen (HBsAg) seroclearance and prevent liver carcinogenesis.
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Affiliation(s)
- Jin Hu
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, 1 Tian-tan Xi-li, Beijing, 100050, China
| | - Junjun Cheng
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
| | - Liudi Tang
- Microbiology and Immunology Graduate Program, Drexel University College of Medicine, 2900 West Queen Lane, Philadelphia, Pennsylvania 19129, United States
| | - Zhanying Hu
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
| | - Yue Luo
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
- Institute of Hepatology, Second Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, Hunan 410008, China
| | - Yuhuan Li
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Science, 1 Tian-tan Xi-li, Beijing, 100050, China
| | - Tianlun Zhou
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
| | - Jinhong Chang
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
| | - Ju-Tao Guo
- Baruch S. Blumberg Institute, 3805 Old Easton Road, Doylestown, Pennsylvania 18902, United States
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37
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Yang F. Post-translational Modification Control of HBV Biological Processes. Front Microbiol 2018; 9:2661. [PMID: 30443247 PMCID: PMC6222169 DOI: 10.3389/fmicb.2018.02661] [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] [Received: 08/14/2018] [Accepted: 10/18/2018] [Indexed: 12/11/2022] Open
Abstract
Hepatitis B virus infection remains a global healthy issue that needs to be urgently solved. Novel strategies for anti-viral therapy are based on exploring the effective diagnostic markers and therapeutic targets of diseases caused by hepatitis B virus (HBV) infection. It is well-established that not only viral proteins themselves but also key factors from the host control the biological processes associated with HBV, including replication, transcription, packaging, and secretion. Protein post-translational modifications (PTMs), such as phosphorylation, acetylation, methylation, and ubiquitination, have been shown to control protein activity, regulate protein stability, promote protein interactions and alter protein subcellular localization, leading to the modulation of crucial signaling pathways and affected cellular processes. This review focuses on the functions and effects of diverse PTMs in regulating important processes in the HBV life cycle. The potential roles of PTMs in the pathogenesis of HBV-associated liver diseases are also discussed.
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Affiliation(s)
- Fan Yang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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Chabrolles H, Lahlali T, Auclair H, Salvetti A. [The multiple functions of the hepatitis B virus core protein: new research directions and therapeutic challenges]. Med Sci (Paris) 2018; 34:693-700. [PMID: 30230454 DOI: 10.1051/medsci/20183408016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Chronic infection by hepatitis B virus (HBV) is a major public health problem with more than 250 millions of people chronically infected worldwide who have a high risk to develop cirrhosis and hepatocellular carcinoma. Available treatments reduce viremia but do not eradicate the virus from hepatocytes. Therefore, there is an urgent need to develop new classes of antiviral molecules and the viral capsid protein, Core, constitutes a new favored target. Core protein Allosteric Modulators (CAMs) targeting its assembly functions are in clinical development. In addition, investigation of Core regulatory functions may lead to the development of compounds targeting cellular factors (HTA) that could be used in combined therapies aiming to achieve a better control of HBV replication.
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Affiliation(s)
- Hélène Chabrolles
- Centre de recherche en cancérologie de Lyon (CRCL), Inserm U1052, 151, cours Albert Thomas, 69003 Lyon, France
| | - Thomas Lahlali
- Centre de recherche en cancérologie de Lyon (CRCL), Inserm U1052, 151, cours Albert Thomas, 69003 Lyon, France
| | - Héloïse Auclair
- Centre de recherche en cancérologie de Lyon (CRCL), Inserm U1052, 151, cours Albert Thomas, 69003 Lyon, France
| | - Anna Salvetti
- Centre de recherche en cancérologie de Lyon (CRCL), Inserm U1052, 151, cours Albert Thomas, 69003 Lyon, France
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Bloom K, Maepa MB, Ely A, Arbuthnot P. Gene Therapy for Chronic HBV-Can We Eliminate cccDNA? Genes (Basel) 2018; 9:E207. [PMID: 29649127 PMCID: PMC5924549 DOI: 10.3390/genes9040207] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 04/05/2018] [Accepted: 04/09/2018] [Indexed: 02/06/2023] Open
Abstract
Chronic infection with the hepatitis B virus (HBV) is a global health concern and accounts for approximately 1 million deaths annually. Amongst other limitations of current anti-HBV treatment, failure to eliminate the viral covalently closed circular DNA (cccDNA) and emergence of resistance remain the most worrisome. Viral rebound from latent episomal cccDNA reservoirs occurs following cessation of therapy, patient non-compliance, or the development of escape mutants. Simultaneous viral co-infections, such as by HIV-1, further complicate therapeutic interventions. These challenges have prompted development of novel targeted hepatitis B therapies. Given the ease with which highly specific and potent nucleic acid therapeutics can be rationally designed, gene therapy has generated interest for antiviral application. Gene therapy strategies developed for HBV include gene silencing by harnessing RNA interference, transcriptional inhibition through epigenetic modification of target DNA, genome editing by designer nucleases, and immune modulation with cytokines. DNA-binding domains and effectors based on the zinc finger (ZF), transcription activator-like effector (TALE), and clustered regularly interspaced short palindromic repeat (CRISPR) systems are remarkably well suited to targeting episomal cccDNA. This review discusses recent developments and challenges facing the field of anti-HBV gene therapy, its potential curative significance and the progress towards clinical application.
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Affiliation(s)
- Kristie Bloom
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Mohube Betty Maepa
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Abdullah Ely
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
| | - Patrick Arbuthnot
- Wits/SAMRC Antiviral Gene Therapy Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Private Bag 3, Johannesburg, WITS 2050, South Africa.
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Hepatitis B Virus Subverts the Autophagy Elongation Complex Atg5-12/16L1 and Does Not Require Atg8/LC3 Lipidation for Viral Maturation. J Virol 2018; 92:JVI.01513-17. [PMID: 29367244 DOI: 10.1128/jvi.01513-17] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/12/2018] [Indexed: 12/23/2022] Open
Abstract
Previous studies indicated that hepatitis B virus (HBV) stimulates autophagy to favor its production. To understand how HBV co-opts autophagy as a proviral machinery, we studied the roles of key autophagy proteins in HBV-replicating liver cell cultures. RNA interference-mediated silencing of Atg5, Atg12, and Atg16L1, which promote autophagophore expansion and LC3 membrane conjugation, interfered with viral core/nucleocapsid (NC) formation/stability and strongly diminished virus yields. Concomitantly, the core/NC membrane association and their sorting to envelope-positive compartments were perturbed. A close inspection of the HBV/autophagy cross talk revealed that the virus depended on Atg12 covalently conjugated to Atg5. In support of this finding, HBV required the E2-like enzymes Atg10 and Atg3, which catalyze or facilitate Atg5-12 conjugation, respectively. Atg10 and Atg3 knockdowns decreased HBV production, while Atg3 overexpression increased virus yields. Mapping analyses demonstrated that the HBV core protein encountered the Atg5-12/16L1 complex via interaction with the intrinsically disordered region of the Atg12 moiety that is dispensable for autophagy function. The role of Atg12 in HBV replication was confirmed by its incorporation into virions. Although the Atg5-12/16L1 complex and Atg3 are essential for LC3 lipidation and, thus, for autophagosome maturation and closure, HBV propagation did not require LC3. Silencing of LC3B, the most abundant LC3 isoform, did not inhibit but rather augmented virus production. Similar augmenting effects were obtained upon overexpression of a dominant negative mutant of Atg4B that blocked the lipid conjugation of the LC3 isoforms and their GABARAP paralogues. Together, our data indicate that HBV subverts early, nondegradative autophagy components as assembly scaffolds, thereby concurrently avoiding autophagosomal destruction.IMPORTANCE Infections with the hepatitis B virus (HBV), an enveloped pararetrovirus, cause about 1 million deaths per year, as current therapies rarely achieve a cure. Understanding the HBV life cycle and concomitant host cell interactions is instrumental to develop new antiviral concepts. Here, we proceeded to dissect the roles of the autophagy machinery in virus propagation. By using RNA interference and overexpression studies in HBV-replicating cell lines, we identified the autophagic Atg5-12/16L1 elongation complex along with Atg10 and Atg3 to be an essential scaffold for HBV nucleocapsid assembly/stability. Deficits in Atg5-12/16L1 and Atg10/Atg3, which normally drive autophagophore membrane expansion, strongly impaired progeny virus yields. HBV gained access to Atg5-12/16L1 via interaction of its core protein with the Atg12 moiety of the complex. In contrast, subsequent autophagosome maturation and closure events were unnecessary for HBV replication, as evidenced by inhibition of Atg8/LC3 conjugation. Interfering with the HBV/Atg12 cross talk may be a tool for virus control.
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