1
|
Muller C, Alain S, Hantz S. Identification of a leucine-zipper motif in pUL51 essential for HCMV replication and potential target for antiviral development. Antiviral Res 2023; 217:105673. [PMID: 37478917 DOI: 10.1016/j.antiviral.2023.105673] [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: 05/30/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 07/23/2023]
Abstract
Human cytomegalovirus (HCMV) can cause serious diseases in immunocompromised patients. Use of current antivirals is limited by their adverse effects and emergence of drug resistance mutations. Thus, new drugs are an urgent need. The terminase complex (pUL56-pUL89-pUL51) represents a target of choice for new antivirals development. pUL51 was shown to be crucial for the cleavage of concatemeric HCMV DNA and viral replication. Its C-terminal part plays a critical role for the terminase complex assembly. However, no interaction domain is clearly identified. Sequence comparison of herpesvirus homologs and protein modelling were performed on pUL51. Importance of a putative interaction domain is validated by the generation of recombinant viruses with specific alanine substitutions of amino acids implicated in the domain. We identified a Leucine-Zipper (LZ) domain involving the leucine residues L126-X6-L133-X6-L140-X6-L147 in C-terminal part of pUL51. These leucines are crucial for viral replication, suggesting the significance for pUL51 structure and function. A mimetic-peptide approach has been used and tested in antiviral assays to validate the interaction domain as a new therapeutic target. Cytotoxicity was evaluated by LDH release measurement. The peptide TAT-HK29, homologous to the pUL51-LZ domain, inhibits HCMV replication by 27% ± 9% at 1.25 μM concentration without cytotoxicity. Our results highlight the importance of a leucine zipper domain in the C-terminal part of pUL51 involving leucines L126, L133, L140 and L147. We also confirm the potential of mimetic peptides to inhibit HCMV replication and the importance to target interaction domains to develop antiviral agents.
Collapse
Affiliation(s)
- Clotilde Muller
- Univ. Limoges, INSERM, CHU Limoges, RESINFIT, U1092, F-87000, Limoges, France
| | - Sophie Alain
- Univ. Limoges, INSERM, CHU Limoges, RESINFIT, U1092, F-87000, Limoges, France; CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), F-87000, Limoges, France
| | - Sébastien Hantz
- Univ. Limoges, INSERM, CHU Limoges, RESINFIT, U1092, F-87000, Limoges, France; CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), F-87000, Limoges, France.
| |
Collapse
|
2
|
Yang Q, Liu Y, Wang M, Wu Y, Bin T, Ou X, Mao S, Huang J, Sun D, Gao Q, Zhao X, Zhang S, Chen S, Liu M, Zhu D, Jia R, Cheng A. Duck plague virus pUL15 performs a nonspecial cleavage activity through its C terminal nuclease domain in vitro. Vet Microbiol 2023; 279:109671. [PMID: 36731190 DOI: 10.1016/j.vetmic.2023.109671] [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: 12/28/2022] [Revised: 01/23/2023] [Accepted: 01/28/2023] [Indexed: 01/30/2023]
Abstract
Duck plague virus (DPV), also known as anatid herpesvirus, is a double-stranded DNA virus and a member of α herpesvirus. DPV pUL15 is a homolog of herpes simplex virus 1 (HSV-1) pUL15, a terminase large subunit, and plays a key role in the cleavage and packaging of the viral concatemeric genome. However, the sequence similarity between DPV pUL15 and its homologs is low, and it is not sure if DPV pUL15 has the potential to cleave the concatemeric genome as same as its homologs. Here, we expressed the C terminal domain of DPV pUL15 to explore the nuclease function of DPV pUL15. The main results showed that (Ⅰ) DPV pUL15 C-terminal domain possesses nonspecific nuclease activity and lacks the DNA binding ability. (Ⅱ) DPV pUL15 nuclease activity needs to coordinate with divalent metal ions and tends to be more active at high temperatures. (Ⅲ) Even though the structure of DPV pUL15 nuclease domain is relatively conserved, the mutations of conserved amino acids on the nuclease domain do not significantly inhibit the nuclease activity.
Collapse
Affiliation(s)
- Qiao Yang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Yiheng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Tian Bin
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Xinxin Zhao
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Dekang Zhu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China; Avian Disease Research Center, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang, Chengdu City, Sichuan 611130, China.
| |
Collapse
|
3
|
Turner DL, Mathias RA. The human cytomegalovirus decathlon: Ten critical replication events provide opportunities for restriction. Front Cell Dev Biol 2022; 10:1053139. [PMID: 36506089 PMCID: PMC9732275 DOI: 10.3389/fcell.2022.1053139] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 11/10/2022] [Indexed: 11/27/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous human pathogen that can cause severe disease in immunocompromised individuals, transplant recipients, and to the developing foetus during pregnancy. There is no protective vaccine currently available, and with only a limited number of antiviral drug options, resistant strains are constantly emerging. Successful completion of HCMV replication is an elegant feat from a molecular perspective, with both host and viral processes required at various stages. Remarkably, HCMV and other herpesviruses have protracted replication cycles, large genomes, complex virion structure and complicated nuclear and cytoplasmic replication events. In this review, we outline the 10 essential stages the virus must navigate to successfully complete replication. As each individual event along the replication continuum poses as a potential barrier for restriction, these essential checkpoints represent potential targets for antiviral development.
Collapse
Affiliation(s)
- Declan L. Turner
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Rommel A. Mathias
- Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia,Department of Biochemistry and Molecular Biology, Monash University, Melbourne, VIC, Australia,*Correspondence: Rommel A. Mathias,
| |
Collapse
|
4
|
Optimization of a Lambda-RED Recombination Method for Rapid Gene Deletion in Human Cytomegalovirus. Int J Mol Sci 2021; 22:ijms221910558. [PMID: 34638896 PMCID: PMC8508972 DOI: 10.3390/ijms221910558] [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: 08/20/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 11/25/2022] Open
Abstract
Human cytomegalovirus (HCMV) continues to be a major cause of morbidity in transplant patients and newborns. However, the functions of many of the more than 282 genes encoded in the HCMV genome remain unknown. The development of bacterial artificial chromosome (BAC) technology contributes to the genetic manipulation of several organisms including HCMV. The maintenance of the HCMV BAC in E. coli cells permits the rapid generation of recombinant viral genomes that can be used to produce viral progeny in cell cultures for the study of gene function. We optimized the Lambda-Red Recombination system to construct HCMV gene deletion mutants rapidly in the complete set of tested genes. This method constitutes a useful tool that allows for the quick generation of a high number of gene deletion mutants, allowing for the analysis of the whole genome to improve our understanding of HCMV gene function. This may also facilitate the development of novel vaccines and therapeutics.
Collapse
|
5
|
Muller C, Alain S, Gourin C, Baumert TF, Ligat G, Hantz S. New Insights into Human Cytomegalovirus pUL52 Structure. Viruses 2021; 13:v13081638. [PMID: 34452502 PMCID: PMC8402748 DOI: 10.3390/v13081638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/02/2021] [Accepted: 08/14/2021] [Indexed: 10/31/2022] Open
Abstract
Human cytomegalovirus (HCMV) can cause serious diseases in immunocompromised patients. Current antiviral inhibitors all target the viral DNA polymerase. They have adverse effects, and prolonged treatment can select for drug resistance mutations. Thus, new drugs targeting other stages of replication are an urgent need. The terminase complex (pUL56-pUL89-pUL51) is highly specific, has no counterpart in the human organism, and thus represents a target of choice for new antivirals development. This complex is required for DNA processing and packaging. pUL52 was shown to be essential for the cleavage of concatemeric HCMV DNA and crucial for viral replication, but its functional domains are not yet identified. Polymorphism analysis was performed by sequencing UL52 from 61 HCMV naive strains and from 14 HCMV strains from patients treated with letermovir. Using sequence alignment and homology modeling, we identified conserved regions and potential functional motifs within the pUL52 sequence. Recombinant viruses were generated with specific serine or alanine substitutions in these putative patterns. Within conserved regions, we identified residues essential for viral replication probably involved in CXXC-like or zinc finger motifs. These results suggest that they are essential for pUL52 structure/function. Thus, these patterns represent potential targets for the development of new antivirals.
Collapse
Affiliation(s)
- Clotilde Muller
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, F-87000 Limoges, France; (C.M.); (S.A.); (C.G.)
| | - Sophie Alain
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, F-87000 Limoges, France; (C.M.); (S.A.); (C.G.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), F-87000 Limoges, France
| | - Claire Gourin
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, F-87000 Limoges, France; (C.M.); (S.A.); (C.G.)
| | - Thomas F. Baumert
- Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 67000 Strasbourg, France;
| | - Gaëtan Ligat
- Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 67000 Strasbourg, France;
- Correspondence: (G.L.); (S.H.)
| | - Sébastien Hantz
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, F-87000 Limoges, France; (C.M.); (S.A.); (C.G.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), F-87000 Limoges, France
- Correspondence: (G.L.); (S.H.)
| |
Collapse
|
6
|
Muller C, Alain S, Baumert TF, Ligat G, Hantz S. Structures and Divergent Mechanisms in Capsid Maturation and Stabilization Following Genome Packaging of Human Cytomegalovirus and Herpesviruses. Life (Basel) 2021; 11:life11020150. [PMID: 33669389 PMCID: PMC7920273 DOI: 10.3390/life11020150] [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: 12/18/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 01/13/2023] Open
Abstract
Herpesviruses are the causative agents of several diseases. Infections are generally mild or asymptomatic in immunocompetent individuals. In contrast, herpesvirus infections continue to contribute to significant morbidity and mortality in immunocompromised patients. Few drugs are available for the treatment of human herpesvirus infections, mainly targeting the viral DNA polymerase. Moreover, no successful therapeutic options are available for the Epstein–Barr virus or human herpesvirus 8. Most licensed drugs share the same mechanism of action of targeting the viral polymerase and thus blocking DNA polymerization. Resistances to antiviral drugs have been observed for human cytomegalovirus, herpes simplex virus and varicella-zoster virus. A new terminase inhibitor, letermovir, recently proved effective against human cytomegalovirus. However, the letermovir has no significant activity against other herpesviruses. New antivirals targeting other replication steps, such as capsid maturation or DNA packaging, and inducing fewer adverse effects are therefore needed. Targeting capsid assembly or DNA packaging provides additional options for the development of new drugs. In this review, we summarize recent findings on capsid assembly and DNA packaging. We also described what is known about the structure and function of capsid and terminase proteins to identify novels targets for the development of new therapeutic options.
Collapse
Affiliation(s)
- Clotilde Muller
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, 87000 Limoges, France; (C.M.); (S.A.)
| | - Sophie Alain
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, 87000 Limoges, France; (C.M.); (S.A.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), 87000 Limoges, France
| | - Thomas F. Baumert
- Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 67000 Strasbourg, France;
- Institut Hospitalo-Universitaire, Pôle Hépato-Digestif, Nouvel Hôpital Civil, 67000 Strasbourg, France
| | - Gaëtan Ligat
- Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 67000 Strasbourg, France;
- Correspondence: (G.L.); (S.H.)
| | - Sébastien Hantz
- INSERM, CHU Limoges, University of Limoges, RESINFIT, U1092, 87000 Limoges, France; (C.M.); (S.A.)
- CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRCHV), 87000 Limoges, France
- Correspondence: (G.L.); (S.H.)
| |
Collapse
|
7
|
Ligat G, Muller C, Alain S, Hantz S. [The terminase complex, a relevant target for the treatment of HCMV infection]. Med Sci (Paris) 2020; 36:367-375. [PMID: 32356713 DOI: 10.1051/medsci/2020063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Human cytomegalovirus (HCMV) is an important ubiquitous opportunistic pathogen that belongs to the betaherpesviridae. Primary HCMV infection is generally asymptomatic in immunocompetent individuals. In contrast, HCMV infection causes serious disease in immunocompromised patients and is the leading cause of congenital viral infection. Although they are effective, the use of conventional molecules is limited by the emergence of resistance and by their toxicity. New antivirals targeting other replication steps and inducing fewer adverse effects are therefore needed. During HCMV replication, DNA packaging is performed by the terminase complex, which cleaves DNA to package the virus genome into the capsid. With no counterpart in mammalian cells, these terminase proteins are ideal targets for highly specific antivirals. A new terminase inhibitor, letermovir, recently proved effective against HCMV in phase III clinical trials. However, its mechanism of action is unclear and it has no significant activity against other herpesvirus or non-human CMV.
Collapse
Affiliation(s)
- Gaëtan Ligat
- Univ. Limoges, Inserm, CHU Limoges, RESINFIT, U1092, 87000 Limoges, France - CHU Limoges, Laboratoire de bactériologie-virologie-hygiène, Centre national de référence des Herpèsvirus (NRCHV), 87000 Limoges, France - Adresse actuelle : Inserm U1110, Institut de Recherche sur les Maladies Virales et Hépatiques, Université de Strasbourg, 3 rue Koeberlé, 67000 Strasbourg, France
| | - Clotilde Muller
- Univ. Limoges, Inserm, CHU Limoges, RESINFIT, U1092, 87000 Limoges, France - CHU Limoges, Laboratoire de bactériologie-virologie-hygiène, Centre national de référence des Herpèsvirus (NRCHV), 87000 Limoges, France
| | - Sophie Alain
- Univ. Limoges, Inserm, CHU Limoges, RESINFIT, U1092, 87000 Limoges, France - CHU Limoges, Laboratoire de bactériologie-virologie-hygiène, Centre national de référence des Herpèsvirus (NRCHV), 87000 Limoges, France
| | - Sébastien Hantz
- Univ. Limoges, Inserm, CHU Limoges, RESINFIT, U1092, 87000 Limoges, France - CHU Limoges, Laboratoire de bactériologie-virologie-hygiène, Centre national de référence des Herpèsvirus (NRCHV), 87000 Limoges, France
| |
Collapse
|
8
|
Theiß J, Sung MW, Holzenburg A, Bogner E. Full-length human cytomegalovirus terminase pUL89 adopts a two-domain structure specific for DNA packaging. PLoS Pathog 2019; 15:e1008175. [PMID: 31809525 PMCID: PMC6897398 DOI: 10.1371/journal.ppat.1008175] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 10/30/2019] [Indexed: 02/07/2023] Open
Abstract
A key step in replication of human cytomegalovirus (HCMV) in the host cell is the generation and packaging of unit-length genomes into preformed capsids. The enzymes involved in this process are the terminases. The HCMV terminase complex consists of two terminase subunits, the ATPase pUL56 and the nuclease pUL89. A potential third component pUL51 has been proposed. Even though the terminase subunit pUL89 has been shown to be essential for DNA packaging and interaction with pUL56, it is not known how pUL89 mechanistically achieves sequence-specific DNA binding and nicking. To identify essential domains and invariant amino acids vis-a-vis nuclease activity and DNA binding, alanine substitutions of predicted motifs were analyzed. The analyses indicated that aspartate 463 is an invariant amino acid for the nuclease activity, while argine 544 is an invariant aa for DNA binding. Structural analysis of recombinant protein using electron microscopy in conjunction with single particle analysis revealed a curvilinear monomer with two distinct domains connected by a thinner hinge-like region that agrees well with the predicted structure. These results allow us to model how the terminase subunit pUL89’s structure may mediate its function. HCMV is a member of the herpesvirus family and represents a major human pathogen causing severe disease in newborns and immunocompromised patients for which the development of new non-nucleosidic antiviral agents are highly important. This manuscript focuses on DNA packaging, which is a target for development of new antivirals. The terminase subunit pUL89 is involved in this process. The paper presents the identification of DNA binding and nuclease motifs with invariant amino acids and highlights its first 3-D surface structure at approx. 3 nm resolution. At this resolution, the calculated 3-D surface structure matches well with the predicted structure. In conjunction with earlier studies it was possible to define structure-function relationships for the HCMV terminase subunit pUL89.
Collapse
Affiliation(s)
- Janine Theiß
- Institute of Virology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Min Woo Sung
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Andreas Holzenburg
- Department of Molecular Science, School of Medicine, The University of Texas Rio Grande Valley, Brownsville-Edinburg-Harlingen, Texas, United States of America
| | - Elke Bogner
- Institute of Virology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
| |
Collapse
|
9
|
Highlighting of a LAGLIDADG and a Zing Finger Motifs Located in the pUL56 Sequence Crucial for HCMV Replication. Viruses 2019; 11:v11121093. [PMID: 31779110 PMCID: PMC6950143 DOI: 10.3390/v11121093] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 02/05/2023] Open
Abstract
The human cytomegalovirus (HCMV) terminase complex is part of DNA-packaging machinery that delivers a unit-length genome into a procapsid. Sequence comparison of herpesvirus homologs allowed us to identify a potential LATLNDIERFL and zinc finger pattern in N-terminal part of pUL56. Recombinant viruses were generated with specific serine or alanine substitutions in these putative patterns. We identified a LATLNDIERFL pattern characteristic of LAGLIDADG homing endonucleases and a metal-binding pattern involving the cysteine and histidine residues C191-X2-C194-X22-C217-X-H219 (CCCH) close to the region conferring letermovir resistance. These patterns are crucial for viral replication, suggesting that they are essential for pUL56 structure and function. Thus, these patterns represent potential targets for the development of new antivirals such as small molecules or peptides and may allow to better understand the letermovir mechanism of action.
Collapse
|
10
|
Ligat G, Cazal R, Hantz S, Alain S. The human cytomegalovirus terminase complex as an antiviral target: a close-up view. FEMS Microbiol Rev 2018; 42:137-145. [PMID: 29361041 PMCID: PMC5972660 DOI: 10.1093/femsre/fuy004] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 01/17/2018] [Indexed: 01/13/2023] Open
Abstract
Human cytomegalovirus (HCMV) is responsible for life-threatening infections in immunocompromised individuals and can cause serious congenital malformations. Available antivirals target the viral polymerase but are subject to cross-resistance and toxicity. New antivirals targeting other replication steps and inducing fewer adverse effects are therefore needed. During HCMV replication, DNA maturation and packaging are performed by the terminase complex, which cleaves DNA to package the genome into the capsid. Identified in herpesviruses and bacteriophages, and with no counterpart in mammalian cells, these terminase proteins are ideal targets for highly specific antivirals. A new terminase inhibitor, letermovir, recently proved effective against HCMV in phase III clinical trials, but the mechanism of action is unclear. Letermovir has no significant activity against other herpesvirus or non-human CMV. This review focuses on the highly conserved mechanism of HCMV DNA-packaging and the potential of the terminase complex to serve as an antiviral target. We describe the intrinsic mechanism of DNA-packaging, highlighting the structure-function relationship of HCMV terminase complex components.
Collapse
Affiliation(s)
- G Ligat
- Université Limoges, INSERM, CHU Limoges, UMR 1092, 2 rue Dr Marcland, 87000 Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRHV), 2 avenue Martin Luther King, 87000 Limoges, France
| | - R Cazal
- Université Limoges, INSERM, CHU Limoges, UMR 1092, 2 rue Dr Marcland, 87000 Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRHV), 2 avenue Martin Luther King, 87000 Limoges, France
| | - S Hantz
- Université Limoges, INSERM, CHU Limoges, UMR 1092, 2 rue Dr Marcland, 87000 Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRHV), 2 avenue Martin Luther King, 87000 Limoges, France
| | - S Alain
- Université Limoges, INSERM, CHU Limoges, UMR 1092, 2 rue Dr Marcland, 87000 Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses (NRHV), 2 avenue Martin Luther King, 87000 Limoges, France
| |
Collapse
|
11
|
Gentry BG, Bogner E, Drach JC. Targeting the terminase: An important step forward in the treatment and prophylaxis of human cytomegalovirus infections. Antiviral Res 2018; 161:116-124. [PMID: 30472161 DOI: 10.1016/j.antiviral.2018.11.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/07/2018] [Accepted: 11/13/2018] [Indexed: 10/27/2022]
Abstract
A key step in the replication of human cytomegalovirus (HCMV) in the host cell is the generation and packaging of unit-length genomes into preformed capsids. Enzymes required for this process are so-called terminases, first described for double-stranded DNA bacteriophages. The HCMV terminase consists of the two subunits, the ATPase pUL56 and the nuclease pUL89, and a potential third component pUL51. The terminase subunits are essential for virus replication and are highly conserved throughout the Herpesviridae family. Together with the portal protein pUL104 they form a powerful biological nanomotor. It has been shown for tailed dsDNA bacteriophages that DNA translocation into preformed capsid needs an extraordinary amount of energy. The HCMV terminase subunit pUL56 provides the required ATP hydrolyzing activity. The necessary nuclease activity to cleave the concatemers into unit-length genomes is mediated by the terminase subunit pUL89. Whether this cleavage is mediated by site-specific duplex nicking has not been demonstrated, however, it is required for packaging. Binding to the portal is a prerequisite for DNA translocation. To date, it is a common view that during translocation the terminase moves along some domains of the DNA by a binding and release mechanism. These critical structures have proven to be outstanding targets for drugs to treat HCMV infections because corresponding structures do not exist in mammalian cells. Herein we examine the HCMV terminase as a target for drugs and review several inhibitors discovered by both lead-directed medicinal chemistry and by target-specific design. In addition to producing clinically active compounds the research also has furthered the understanding of the role and function of the terminase itself.
Collapse
Affiliation(s)
- Brian G Gentry
- Drake University College of Pharmacy and Health Sciences, 2507 University Ave., Des Moines, 50311, IA, USA.
| | - Elke Bogner
- Institute of Virology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| | - John C Drach
- University of Michigan School of Dentistry, 1101 N. University Ave., Ann Arbor, 48109, MI, USA.
| |
Collapse
|
12
|
Ligat G, Da Re S, Alain S, Hantz S. Identification of Amino Acids Essential for Viral Replication in the HCMV Helicase-Primase Complex. Front Microbiol 2018; 9:2483. [PMID: 30405556 PMCID: PMC6205958 DOI: 10.3389/fmicb.2018.02483] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 09/28/2018] [Indexed: 12/14/2022] Open
Abstract
Promising new inhibitors that target the viral helicase-primase complex have been reported to block replication of herpes simplex and varicella-zoster viruses, but they have no activity against human cytomegalovirus (HCMV), another herpesvirus. The HCMV helicase-primase complex (pUL105-pUL102-pUL70) is essential for viral DNA replication and could thus be a relevant antiviral target. The roles of the individual subunits composing this complex remain to be defined. By using sequence alignment of herpesviruses homologs, we identified conserved amino acids in the putative pUL105 ATP binding site and in the putative pUL70 zinc finger pattern. Mutational analysis of several of these amino acids both in pUL105 and pUL70, proved that they are crucial for viral replication. We also constructed, by homology modeling, a theoretical structure of the pUL105 N-terminal domain which indicates that the mutated conserved amino acids in this domain could be involved in ATP hydrolysis.
Collapse
Affiliation(s)
- Gaetan Ligat
- U1092, RESINFIT, CHU Limoges, INSERM, University of Limoges, Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses, Limoges, France
| | - Sandra Da Re
- U1092, RESINFIT, CHU Limoges, INSERM, University of Limoges, Limoges, France
| | - Sophie Alain
- U1092, RESINFIT, CHU Limoges, INSERM, University of Limoges, Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses, Limoges, France
| | - Sébastien Hantz
- U1092, RESINFIT, CHU Limoges, INSERM, University of Limoges, Limoges, France.,CHU Limoges, Laboratoire de Bactériologie-Virologie-Hygiène, National Reference Center for Herpesviruses, Limoges, France
| |
Collapse
|
13
|
Neuber S, Wagner K, Messerle M, Borst EM. The C-terminal part of the human cytomegalovirus terminase subunit pUL51 is central for terminase complex assembly. J Gen Virol 2018; 99:119-134. [DOI: 10.1099/jgv.0.000984] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Affiliation(s)
- Sebastian Neuber
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Karen Wagner
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Eva Maria Borst
- Institute of Virology, Hannover Medical School, Hannover, Germany
| |
Collapse
|