1
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Hu Y, Delviks-Frankenberry KA, Wu C, Arizaga F, Pathak VK, Xiong Y. Structural insights into PPP2R5A degradation by HIV-1 Vif. Nat Struct Mol Biol 2024:10.1038/s41594-024-01314-6. [PMID: 38789685 DOI: 10.1038/s41594-024-01314-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 04/11/2024] [Indexed: 05/26/2024]
Abstract
HIV-1 Vif recruits host cullin-RING-E3 ubiquitin ligase and CBFβ to degrade the cellular APOBEC3 antiviral proteins through diverse interactions. Recent evidence has shown that Vif also degrades the regulatory subunits PPP2R5(A-E) of cellular protein phosphatase 2A to induce G2/M cell cycle arrest. As PPP2R5 proteins bear no functional or structural resemblance to A3s, it is unclear how Vif can recognize different sets of proteins. Here we report the cryogenic-electron microscopy structure of PPP2R5A in complex with HIV-1 Vif-CBFβ-elongin B-elongin C at 3.58 Å resolution. The structure shows PPP2R5A binds across the Vif molecule, with biochemical and cellular studies confirming a distinct Vif-PPP2R5A interface that partially overlaps with those for A3s. Vif also blocks a canonical PPP2R5A substrate-binding site, indicating that it suppresses the phosphatase activities through both degradation-dependent and degradation-independent mechanisms. Our work identifies critical Vif motifs regulating the recognition of diverse A3 and PPP2R5A substrates, whereby disruption of these host-virus protein interactions could serve as potential targets for HIV-1 therapeutics.
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Affiliation(s)
- Yingxia Hu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Krista A Delviks-Frankenberry
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, USA
| | - Chunxiang Wu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Fidel Arizaga
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vinay K Pathak
- Viral Mutation Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD, USA.
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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2
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Grandgenett DP, Engelman AN. Brief Histories of Retroviral Integration Research and Associated International Conferences. Viruses 2024; 16:604. [PMID: 38675945 PMCID: PMC11054761 DOI: 10.3390/v16040604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/05/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
The field of retroviral integration research has a long history that started with the provirus hypothesis and subsequent discoveries of the retroviral reverse transcriptase and integrase enzymes. Because both enzymes are essential for retroviral replication, they became valued targets in the effort to discover effective compounds to inhibit HIV-1 replication. In 2007, the first integrase strand transfer inhibitor was licensed for clinical use, and subsequently approved second-generation integrase inhibitors are now commonly co-formulated with reverse transcriptase inhibitors to treat people living with HIV. International meetings specifically focused on integrase and retroviral integration research first convened in 1995, and this paper is part of the Viruses Special Issue on the 7th International Conference on Retroviral Integration, which was held in Boulder Colorado in the summer of 2023. Herein, we overview key historical developments in the field, especially as they pertain to the development of the strand transfer inhibitor drug class. Starting from the mid-1990s, research advancements are presented through the lens of the international conferences. Our overview highlights the impact that regularly scheduled, subject-specific international meetings can have on community-building and, as a result, on field-specific collaborations and scientific advancements.
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Affiliation(s)
- Duane P. Grandgenett
- Department of Molecular Microbiology and Immunology, School of Medicine, Saint Louis University, St. Louis, MO 63104, USA
| | - Alan N. Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02215, USA
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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3
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Zuo X, Zhou R, Yang S, Ma G. HTLV-1 persistent infection and ATLL oncogenesis. J Med Virol 2023; 95:e28424. [PMID: 36546414 DOI: 10.1002/jmv.28424] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 12/08/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022]
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus; whereas HTLV-1 mainly persists in the infected host cell as a provirus, it also causes a malignancy called adult T-cell leukemia/lymphoma (ATLL) in about 5% of infection. HTLV-1 replication is in most cases silent in vivo and viral de novo infection rarely occurs; HTLV-1 rather relies on clonal proliferation of infected T cells for viral propagation as it multiplies the number of the provirus copies. It is mechanistically elusive how leukemic clones emerge during the course of HTLV-1 infection in vivo and eventually cause the onset of ATLL. This review summarizes our current understanding of HTLV-1 persistence and oncogenesis, with the incorporation of recent cutting-edge discoveries obtained by high-throughput sequencing.
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Affiliation(s)
- Xiaorui Zuo
- Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, China.,State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Ruoning Zhou
- Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, China.,State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Sikai Yang
- Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, China.,State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
| | - Guangyong Ma
- Institute of Pharmaceutical Science, China Pharmaceutical University, Nanjing, China.,State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, China
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4
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Pellaers E, Bhat A, Christ F, Debyser Z. Determinants of Retroviral Integration and Implications for Gene Therapeutic MLV-Based Vectors and for a Cure for HIV-1 Infection. Viruses 2022; 15:32. [PMID: 36680071 PMCID: PMC9861059 DOI: 10.3390/v15010032] [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: 11/30/2022] [Revised: 12/14/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
To complete their replication cycle, retroviruses need to integrate a DNA copy of their RNA genome into a host chromosome. Integration site selection is not random and is driven by multiple viral and cellular host factors specific to different classes of retroviruses. Today, overwhelming evidence from cell culture, animal experiments and clinical data suggests that integration sites are important for retroviral replication, oncogenesis and/or latency. In this review, we will summarize the increasing knowledge of the mechanisms underlying the integration site selection of the gammaretrovirus MLV and the lentivirus HIV-1. We will discuss how host factors of the integration site selection of retroviruses may steer the development of safer viral vectors for gene therapy. Next, we will discuss how altering the integration site preference of HIV-1 using small molecules could lead to a cure for HIV-1 infection.
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Affiliation(s)
| | | | | | - Zeger Debyser
- Molecular Virology and Gene Therapy, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
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5
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Luperchio AM, Jónsson SR, Salamango DJ. Evolutionary Conservation of PP2A Antagonism and G2/M Cell Cycle Arrest in Maedi-Visna Virus Vif. Viruses 2022; 14:1701. [PMID: 36016323 PMCID: PMC9413702 DOI: 10.3390/v14081701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/29/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022] Open
Abstract
The canonical function of lentiviral Vif proteins is to counteract the mutagenic potential of APOBEC3 antiviral restriction factors. However, recent studies have discovered that Vif proteins from diverse HIV-1 and simian immunodeficiency virus (SIV) isolates degrade cellular B56 phosphoregulators to remodel the host phosphoproteome and induce G2/M cell cycle arrest. Here, we evaluate the conservation of this activity among non-primate lentiviral Vif proteins using fluorescence-based degradation assays and demonstrate that maedi-visna virus (MVV) Vif efficiently degrades all five B56 family members. Testing an extensive panel of single amino acid substitution mutants revealed that MVV Vif recognizes B56 proteins through a conserved network of electrostatic interactions. Furthermore, experiments using genetic and pharmacologic approaches demonstrate that degradation of B56 proteins requires the cellular cofactor cyclophilin A. Lastly, MVV Vif-mediated depletion of B56 proteins induces a potent G2/M cell cycle arrest phenotype. Therefore, remodeling of the cellular phosphoproteome and induction of G2/M cell cycle arrest are ancient and conserved functions of lentiviral Vif proteins, which suggests that they are advantageous for lentiviral pathogenesis.
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Affiliation(s)
- Adeline M. Luperchio
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, NY 11794, USA;
| | - Stefán R. Jónsson
- Institute for Experimental Pathology, University of Iceland, Keldur, 112 Reykjavik, Iceland;
| | - Daniel J. Salamango
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, NY 11794, USA;
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6
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Machado CB, da Cunha LS, Maués JHDS, Pessoa FMCDP, de Oliveira MB, Ribeiro RM, Lopes GS, de Moraes Filho MO, de Moraes MEA, Khayat AS, Moreira-Nunes CA. Role of miRNAs in Human T Cell Leukemia Virus Type 1 Induced T Cell Leukemia: A Literature Review and Bioinformatics Approach. Int J Mol Sci 2022; 23:ijms23105486. [PMID: 35628297 PMCID: PMC9141946 DOI: 10.3390/ijms23105486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 05/10/2022] [Accepted: 05/11/2022] [Indexed: 02/06/2023] Open
Abstract
Human T cell leukemia virus type 1 (HTLV-1) was identified as the first pathogenic human retrovirus and is estimated to infect 5 to 10 million individuals worldwide. Unlike other retroviruses, there is no effective therapy to prevent the onset of the most alarming diseases caused by HTLV-1, and the more severe cases manifest as the malignant phenotype of adult T cell leukemia (ATL). MicroRNA (miRNA) dysfunction is a common feature of leukemogenesis, and it is no different in ATL cases. Therefore, we sought to analyze studies that reported deregulated miRNA expression in HTLV-1 infected cells and patients’ samples to understand how this deregulation could induce malignancy. Through in silico analysis, we identified 12 miRNAs that stood out in the prediction of targets, and we performed functional annotation of the genes linked to these 12 miRNAs that appeared to have a major biological interaction. A total of 90 genes were enriched in 14 KEGG pathways with significant values, including TP53, WNT, MAPK, TGF-β, and Ras signaling pathways. These miRNAs and gene interactions are discussed in further detail for elucidation of how they may act as probable drivers for ATL onset, and while our data provide solid starting points for comprehension of miRNAs’ roles in HTLV-1 infection, continuous effort in oncologic research is still needed to improve our understanding of HTLV-1 induced leukemia.
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Affiliation(s)
- Caio Bezerra Machado
- Department of Medicine, Pharmacogenetics Laboratory, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, CE, Brazil; (C.B.M.); (F.M.C.d.P.P.); (M.O.d.M.F.); (M.E.A.d.M.)
| | | | | | - Flávia Melo Cunha de Pinho Pessoa
- Department of Medicine, Pharmacogenetics Laboratory, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, CE, Brazil; (C.B.M.); (F.M.C.d.P.P.); (M.O.d.M.F.); (M.E.A.d.M.)
| | - Marcelo Braga de Oliveira
- Department of Biological Sciences, Oncology Research Center, Federal University of Pará, Belém 66073-005, PA, Brazil; (M.B.d.O.); (A.S.K.)
| | | | - Germison Silva Lopes
- Department of Hematology, César Cals General Hospital, Fortaleza 60015-152, CE, Brazil;
| | - Manoel Odorico de Moraes Filho
- Department of Medicine, Pharmacogenetics Laboratory, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, CE, Brazil; (C.B.M.); (F.M.C.d.P.P.); (M.O.d.M.F.); (M.E.A.d.M.)
| | - Maria Elisabete Amaral de Moraes
- Department of Medicine, Pharmacogenetics Laboratory, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, CE, Brazil; (C.B.M.); (F.M.C.d.P.P.); (M.O.d.M.F.); (M.E.A.d.M.)
| | - André Salim Khayat
- Department of Biological Sciences, Oncology Research Center, Federal University of Pará, Belém 66073-005, PA, Brazil; (M.B.d.O.); (A.S.K.)
| | - Caroline Aquino Moreira-Nunes
- Department of Medicine, Pharmacogenetics Laboratory, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, CE, Brazil; (C.B.M.); (F.M.C.d.P.P.); (M.O.d.M.F.); (M.E.A.d.M.)
- Unichristus University Center, Faculty of Biomedicine, Fortaleza 60430-275, CE, Brazil;
- Department of Biological Sciences, Oncology Research Center, Federal University of Pará, Belém 66073-005, PA, Brazil; (M.B.d.O.); (A.S.K.)
- Department of Health Sciences, Northeast Biotechnology Network (RENORBIO), Itaperi Campus, Ceará State University, Fortaleza 60740-903, CE, Brazil
- Correspondence:
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7
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Miura M, Naito T, Saito M. Current Perspectives in Human T-Cell Leukemia Virus Type 1 Infection and Its Associated Diseases. Front Med (Lausanne) 2022; 9:867478. [PMID: 35463007 PMCID: PMC9024061 DOI: 10.3389/fmed.2022.867478] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 03/15/2022] [Indexed: 11/25/2022] Open
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is a replication-competent human retrovirus associated with two distinct types of diseases: a malignancy of mature CD4+ T cells called adult T-cell leukemia-lymphoma (ATL) and a chronic inflammatory central nervous system disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It was the first human retrovirus ever associated with a human cancer. Although most HTLV-1-infected individuals remain asymptomatic for life, a subpopulation develops ATL or HAM/TSP. Although the factors that cause these different manifestations of HTLV-1 infection are not fully understood, accumulating evidence suggests that the complex virus-host interactions, as well as the host immune response against HTLV-1 infection, appear to regulate the development of HTLV-1-associated diseases. This review outlines and discusses the current understanding, ongoing developments, and future perspectives of HTLV-1 research.
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8
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Abstract
A hallmark of retroviral replication is establishment of the proviral state, wherein a DNA copy of the viral RNA genome is stably incorporated into a host cell chromosome. Integrase is the viral enzyme responsible for the catalytic steps involved in this process, and integrase strand transfer inhibitors are widely used to treat people living with HIV. Over the past decade, a series of X-ray crystallography and cryogenic electron microscopy studies have revealed the structural basis of retroviral DNA integration. A variable number of integrase molecules congregate on viral DNA ends to assemble a conserved intasome core machine that facilitates integration. The structures additionally informed on the modes of integrase inhibitor action and the means by which HIV acquires drug resistance. Recent years have witnessed the development of allosteric integrase inhibitors, a highly promising class of small molecules that antagonize viral morphogenesis. In this Review, we explore recent insights into the organization and mechanism of the retroviral integration machinery and highlight open questions as well as new directions in the field.
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9
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Passos DO, Li M, Craigie R, Lyumkis D. Retroviral integrase: Structure, mechanism, and inhibition. Enzymes 2021; 50:249-300. [PMID: 34861940 DOI: 10.1016/bs.enz.2021.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The retroviral protein Integrase (IN) catalyzes concerted integration of viral DNA into host chromatin to establish a permanent infection in the target cell. We learned a great deal about the mechanism of catalytic integration through structure/function studies over the previous four decades of IN research. As one of three essential retroviral enzymes, IN has also been targeted by antiretroviral drugs to treat HIV-infected individuals. Inhibitors blocking the catalytic integration reaction are now state-of-the-art drugs within the antiretroviral therapy toolkit. HIV-1 IN also performs intriguing non-catalytic functions that are relevant to the late stages of the viral replication cycle, yet this aspect remains poorly understood. There are also novel allosteric inhibitors targeting non-enzymatic functions of IN that induce a block in the late stages of the viral replication cycle. In this chapter, we will discuss the function, structure, and inhibition of retroviral IN proteins, highlighting remaining challenges and outstanding questions.
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Affiliation(s)
| | - Min Li
- National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States
| | - Robert Craigie
- National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States
| | - Dmitry Lyumkis
- The Salk Institute for Biological Studies, La Jolla, CA, United States; The Scripps Research Institute, La Jolla, CA, United States.
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10
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Barski MS, Vanzo T, Zhao XZ, Smith SJ, Ballandras-Colas A, Cronin NB, Pye VE, Hughes SH, Burke TR, Cherepanov P, Maertens GN. Structural basis for the inhibition of HTLV-1 integration inferred from cryo-EM deltaretroviral intasome structures. Nat Commun 2021; 12:4996. [PMID: 34404793 PMCID: PMC8370991 DOI: 10.1038/s41467-021-25284-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 07/20/2021] [Indexed: 02/07/2023] Open
Abstract
Between 10 and 20 million people worldwide are infected with the human T-cell lymphotropic virus type 1 (HTLV-1). Despite causing life-threatening pathologies there is no therapeutic regimen for this deltaretrovirus. Here, we screened a library of integrase strand transfer inhibitor (INSTI) candidates built around several chemical scaffolds to determine their effectiveness in limiting HTLV-1 infection. Naphthyridines with substituents in position 6 emerged as the most potent compounds against HTLV-1, with XZ450 having highest efficacy in vitro. Using single-particle cryo-electron microscopy we visualised XZ450 as well as the clinical HIV-1 INSTIs raltegravir and bictegravir bound to the active site of the deltaretroviral intasome. The structures reveal subtle differences in the coordination environment of the Mg2+ ion pair involved in the interaction with the INSTIs. Our results elucidate the binding of INSTIs to the HTLV-1 intasome and support their use for pre-exposure prophylaxis and possibly future treatment of HTLV-1 infection.
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Affiliation(s)
- Michal S Barski
- Imperial College London, St. Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, UK
- International Institute of Molecular Mechanisms and Machines, Polish Academy of Sciences, Warsaw, Poland
| | - Teresa Vanzo
- Imperial College London, St. Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, UK
- Department CIBIO, University of Trento, Povo-Trento, Italy
| | - Xue Zhi Zhao
- Chemical Biology Laboratory, Centre for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Steven J Smith
- Retroviral Replication Laboratory, Centre for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | | | - Nora B Cronin
- LonCEM Facility, The Francis Crick Institute, London, UK
| | - Valerie E Pye
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Stephen H Hughes
- Retroviral Replication Laboratory, Centre for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Terrence R Burke
- Chemical Biology Laboratory, Centre for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Peter Cherepanov
- Imperial College London, St. Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, UK
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Goedele N Maertens
- Imperial College London, St. Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, UK.
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11
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Barski MS, Minnell JJ, Maertens GN. PP2A Phosphatase as an Emerging Viral Host Factor. Front Cell Infect Microbiol 2021; 11:725615. [PMID: 34422684 PMCID: PMC8371333 DOI: 10.3389/fcimb.2021.725615] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/20/2021] [Indexed: 12/12/2022] Open
Abstract
Protein phosphatase 2A (PP2A) is one of the most ubiquitous cellular proteins and is responsible for the vast majority of Ser/Thr phosphatase activity in eukaryotes. PP2A is a heterotrimer, and its assembly, intracellular localization, enzymatic activity, and substrate specificity are subject to dynamic regulation. Each of its subunits can be targeted by viral proteins to hijack and modulate its activity and downstream signaling to the advantage of the virus. Binding to PP2A is known to be essential to the life cycle of many viruses and seems to play a particularly crucial role for oncogenic viruses, which utilize PP2A to transform infected cells through controlling the cell cycle and apoptosis. Here we summarise the latest developments in the field of PP2A viral targeting; in particular recent discoveries of PP2A hijacking through molecular mimicry of a B56-specific motif by several different viruses. We also discuss the potential as well as shortcomings for therapeutic intervention in the face of our current understanding of viral PP2A targeting.
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Affiliation(s)
| | | | - Goedele Noella Maertens
- Department of Infectious Disease, Section of Molecular Virology, St Mary’s Hospital, Imperial College London, London, United Kingdom
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12
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Protein Phosphatase 2A (PP2A) mutations in brain function, development, and neurologic disease. Biochem Soc Trans 2021; 49:1567-1588. [PMID: 34241636 DOI: 10.1042/bst20201313] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 12/15/2022]
Abstract
By removing Ser/Thr-specific phosphorylations in a multitude of protein substrates in diverse tissues, Protein Phosphatase type 2A (PP2A) enzymes play essential regulatory roles in cellular signalling and physiology, including in brain function and development. Here, we review current knowledge on PP2A gene mutations causally involved in neurodevelopmental disorders and intellectual disability, focusing on PPP2CA, PPP2R1A and PPP2R5D. We provide insights into the impact of these mutations on PP2A structure, substrate specificity and potential function in neurobiology and brain development.
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13
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Yoder KE, Rabe AJ, Fishel R, Larue RC. Strategies for Targeting Retroviral Integration for Safer Gene Therapy: Advances and Challenges. Front Mol Biosci 2021; 8:662331. [PMID: 34055882 PMCID: PMC8149907 DOI: 10.3389/fmolb.2021.662331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/29/2021] [Indexed: 12/11/2022] Open
Abstract
Retroviruses are obligate intracellular parasites that must integrate a copy of the viral genome into the host DNA. The integration reaction is performed by the viral enzyme integrase in complex with the two ends of the viral cDNA genome and yields an integrated provirus. Retroviral vector particles are attractive gene therapy delivery tools due to their stable integration. However, some retroviral integration events may dysregulate host oncogenes leading to cancer in gene therapy patients. Multiple strategies to target retroviral integration, particularly to genetic safe harbors, have been tested with limited success. Attempts to target integration may be limited by the multimerization of integrase or the presence of host co-factors for integration. Several retroviral integration complexes have evolved a mechanism of tethering to chromatin via a host protein. Integration host co-factors bind chromatin, anchoring the complex and allowing integration. The tethering factor allows for both close proximity to the target DNA and specificity of targeting. Each retrovirus appears to have distinct preferences for DNA sequence and chromatin features at the integration site. Tethering factors determine the preference for chromatin features, but do not affect the subtle sequence preference at the integration site. The sequence preference is likely intrinsic to the integrase protein. New developments may uncouple the requirement for a tethering factor and increase the ability to redirect retroviral integration.
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Affiliation(s)
- Kristine E Yoder
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Anthony J Rabe
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Richard Fishel
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Ross C Larue
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, United States
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14
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Kotlar RM, Jones ND, Senavirathne G, Gardner AM, Messer RK, Tan YY, Rabe AJ, Fishel R, Yoder KE. Retroviral prototype foamy virus intasome binding to a nucleosome target does not determine integration efficiency. J Biol Chem 2021; 296:100550. [PMID: 33744295 PMCID: PMC8050864 DOI: 10.1016/j.jbc.2021.100550] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/12/2021] [Accepted: 03/16/2021] [Indexed: 01/15/2023] Open
Abstract
Retroviral integrases must navigate host DNA packaged as chromatin during integration of the viral genome. Prototype foamy virus (PFV) integrase (IN) forms a tetramer bound to two viral DNA (vDNA) ends in a complex termed an intasome. PFV IN consists of four domains: the amino terminal extension domain (NED), amino terminal domain (NTD), catalytic core domain (CCD), and carboxyl terminal domain (CTD). The domains of the two inner IN protomers have been visualized, as well as the CCDs of the two outer IN protomers. However, the roles of the amino and carboxyl terminal domains of the PFV intasome outer subunits during integration to a nucleosome target substrate are not clear. We used the well-characterized 601 nucleosome to assay integration activity as well as intasome binding. PFV intasome integration to 601 nucleosomes occurs in clusters at four independent sites. We find that the outer protomer NED and NTD domains have no significant effects on integration efficiency, site selection, or binding. The CTDs of the outer PFV intasome subunits dramatically affect nucleosome binding but have little effect on total integration efficiency. The outer PFV IN CTDs did significantly alter the integration efficiency at one site. Histone tails also significantly affect intasome binding, but have little impact on PFV integration efficiency or site selection. These results indicate that binding to nucleosomes does not correlate with integration efficiency and suggests most intasome-binding events are unproductive.
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Affiliation(s)
- Randi M Kotlar
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Nathan D Jones
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Gayan Senavirathne
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Anne M Gardner
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Ryan K Messer
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Yow Yong Tan
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Anthony J Rabe
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Richard Fishel
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA
| | - Kristine E Yoder
- Cancer Biology and Genetics, The Ohio State University College of Medicine, Columbus, Ohio, USA; The Ohio State University Comprehensive Cancer Center, Columbus, Ohio, USA.
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15
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Salamango DJ, Harris RS. Dual Functionality of HIV-1 Vif in APOBEC3 Counteraction and Cell Cycle Arrest. Front Microbiol 2021; 11:622012. [PMID: 33510734 PMCID: PMC7835321 DOI: 10.3389/fmicb.2020.622012] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 12/11/2020] [Indexed: 01/02/2023] Open
Abstract
Accessory proteins are a key feature that distinguishes primate immunodeficiency viruses such as human immunodeficiency virus type I (HIV-1) from other retroviruses. A prime example is the virion infectivity factor, Vif, which hijacks a cellular co-transcription factor (CBF-β) to recruit a ubiquitin ligase complex (CRL5) to bind and degrade antiviral APOBEC3 enzymes including APOBEC3D (A3D), APOBEC3F (A3F), APOBEC3G (A3G), and APOBEC3H (A3H). Although APOBEC3 antagonism is essential for viral pathogenesis, and a more than sufficient functional justification for Vif’s evolution, most viral proteins have evolved multiple functions. Indeed, Vif has long been known to trigger cell cycle arrest and recent studies have shed light on the underlying molecular mechanism. Vif accomplishes this function using the same CBF-β/CRL5 ubiquitin ligase complex to degrade a family of PPP2R5 phospho-regulatory proteins. These advances have helped usher in a new era of accessory protein research and fresh opportunities for drug development.
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Affiliation(s)
- Daniel J Salamango
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, United States
| | - Reuben S Harris
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States.,Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States.,Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, United States.,Howard Hughes Medical Institute, University of Minnesota, Minneapolis, MN, United States
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16
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Functional and Structural Insights into a Vif/PPP2R5 Complex Elucidated Using Patient HIV-1 Isolates and Computational Modeling. J Virol 2020; 94:JVI.00631-20. [PMID: 32847850 DOI: 10.1128/jvi.00631-20] [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: 04/06/2020] [Accepted: 08/17/2020] [Indexed: 02/06/2023] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) Vif recruits a cellular ubiquitin ligase complex to degrade antiviral APOBEC3 enzymes (APOBEC3C-H) and PP2A phosphatase regulators (PPP2R5A to PPP2R5E). While APOBEC3 antagonism is the canonical function of HIV-1 Vif, this viral accessory protein is also known to trigger G2/M cell cycle arrest. Vif initiates G2/M arrest by degrading multiple PPP2R5 family members, an activity prevalent among diverse HIV-1 and simian immunodeficiency virus (SIV) isolates. Here, computational protein-protein docking was used to delineate a Vif/CBF-β/PPP2R5 complex in which Vif is predicted to bind the same PPP2R5 surface as physiologic phosphatase targets. This model was tested using targeted mutagenesis of amino acid residues within or adjacent to the putative interface to show loss or retention, respectively, of Vif-induced PPP2R5 degradation activity. Additionally, expression of a peptide that mimics cellular targets of PPP2R5s robustly inhibited Vif-mediated degradation of PPP2R5A but not APOBEC3G. Moreover, live-cell imaging studies examining Vif-mediated degradation of PPP2R5A and APOBEC3G within the same cell revealed that PPP2R5A degradation kinetics are comparable to those of APOBEC3G with a half-life of roughly 6 h postinfection, demonstrating that Vif can concurrently mediate the degradation of distinct cellular substrates. Finally, experiments with a panel of patient-derived Vif isolates indicated that PPP2R5A degradation activity is common in patient-derived isolates. Taken together, these results support a model in which PPP2R5 degradation and global changes in the cellular phosphoproteome are likely to be advantageous for viral pathogenesis.IMPORTANCE A critical function of HIV-1 Vif is to counteract the family of APOBEC3 innate immune proteins. It is also widely accepted that Vif induces G2/M cell cycle arrest in several different cell types. Recently, it has been shown that Vif degrades multiple PPP2R5 phosphoregulators to induce the G2/M arrest phenotype. Here, computational approaches are used to test a structural model of the Vif/PPP2R5 complex. In addition, imaging studies are used to show that Vif degrades these PPP2R5 substrates in roughly the same time frame as APOBEC3 degradation and that this activity is prevalent in patient-derived Vif isolates. These studies are important by further defining PPP2R5 proteins as a bona fide substrate of HIV-1 Vif.
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17
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Barski MS, Minnell JJ, Hodakova Z, Pye VE, Nans A, Cherepanov P, Maertens GN. Cryo-EM structure of the deltaretroviral intasome in complex with the PP2A regulatory subunit B56γ. Nat Commun 2020; 11:5043. [PMID: 33028863 PMCID: PMC7542444 DOI: 10.1038/s41467-020-18874-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/15/2020] [Indexed: 01/07/2023] Open
Abstract
Human T-cell lymphotropic virus type 1 (HTLV-1) is a deltaretrovirus and the most oncogenic pathogen. Many of the ~20 million HTLV-1 infected people will develop severe leukaemia or an ALS-like motor disease, unless a therapy becomes available. A key step in the establishment of infection is the integration of viral genetic material into the host genome, catalysed by the retroviral integrase (IN) enzyme. Here, we use X-ray crystallography and single-particle cryo-electron microscopy to determine the structure of the functional deltaretroviral IN assembled on viral DNA ends and bound to the B56γ subunit of its human host factor, protein phosphatase 2 A. The structure reveals a tetrameric IN assembly bound to two molecules of the phosphatase via a conserved short linear motif. Insight into the deltaretroviral intasome and its interaction with the host will be crucial for understanding the pattern of integration events in infected individuals and therefore bears important clinical implications.
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MESH Headings
- Amino Acid Motifs/genetics
- Cloning, Molecular
- Cryoelectron Microscopy
- Crystallography, X-Ray
- DNA, Viral/metabolism
- DNA, Viral/ultrastructure
- Human T-lymphotropic virus 1/enzymology
- Human T-lymphotropic virus 1/genetics
- Human T-lymphotropic virus 1/pathogenicity
- Humans
- Integrases/genetics
- Integrases/metabolism
- Integrases/ultrastructure
- Leukemia-Lymphoma, Adult T-Cell/pathology
- Leukemia-Lymphoma, Adult T-Cell/virology
- Molecular Docking Simulation
- Mutagenesis, Site-Directed
- Paraparesis, Tropical Spastic/pathology
- Paraparesis, Tropical Spastic/virology
- Protein Multimerization
- Protein Phosphatase 2/genetics
- Protein Phosphatase 2/metabolism
- Protein Phosphatase 2/ultrastructure
- Protein Structure, Quaternary
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Recombinant Proteins/ultrastructure
- Sequence Homology, Amino Acid
- Simian T-lymphotropic virus 1/enzymology
- Simian T-lymphotropic virus 1/genetics
- Single Molecule Imaging
- Viral Proteins/genetics
- Viral Proteins/metabolism
- Viral Proteins/ultrastructure
- Virus Integration
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Affiliation(s)
- Michał S Barski
- Imperial College London, St Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, W2 1PG, UK
| | - Jordan J Minnell
- Imperial College London, St Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, W2 1PG, UK
| | - Zuzana Hodakova
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Valerie E Pye
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Andrea Nans
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Peter Cherepanov
- Imperial College London, St Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, W2 1PG, UK
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Goedele N Maertens
- Imperial College London, St Mary's Hospital, Department of Infectious Disease, Section of Virology, Norfolk Place, London, W2 1PG, UK.
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18
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Bhatt V, Shi K, Salamango DJ, Moeller NH, Pandey KK, Bera S, Bohl HO, Kurniawan F, Orellana K, Zhang W, Grandgenett DP, Harris RS, Sundborger-Lunna AC, Aihara H. Structural basis of host protein hijacking in human T-cell leukemia virus integration. Nat Commun 2020; 11:3121. [PMID: 32561747 PMCID: PMC7305164 DOI: 10.1038/s41467-020-16963-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022] Open
Abstract
Integration of the reverse-transcribed viral DNA into host chromosomes is a critical step in the life-cycle of retroviruses, including an oncogenic delta(δ)-retrovirus human T-cell leukemia virus type-1 (HTLV-1). Retroviral integrase forms a higher order nucleoprotein assembly (intasome) to catalyze the integration reaction, in which the roles of host factors remain poorly understood. Here, we use cryo-electron microscopy to visualize the HTLV-1 intasome at 3.7-Å resolution. The structure together with functional analyses reveal that the B56γ (B'γ) subunit of an essential host enzyme, protein phosphatase 2 A (PP2A), is repurposed as an integral component of the intasome to mediate HTLV-1 integration. Our studies reveal a key host-virus interaction underlying the replication of an important human pathogen and highlight divergent integration strategies of retroviruses.
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Affiliation(s)
- Veer Bhatt
- The Hormel Institute, University of Minnesota, 801 16th Avenue N.E., Austin, MN, 55912, USA
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
| | - Ke Shi
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Daniel J Salamango
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Nicholas H Moeller
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Krishan K Pandey
- Department of Molecular Microbiology and Immunology, Saint Louis University, 1100 S. Grand Boulevard, St. Louis, MO, 63104, USA
| | - Sibes Bera
- Department of Molecular Microbiology and Immunology, Saint Louis University, 1100 S. Grand Boulevard, St. Louis, MO, 63104, USA
| | - Heather O Bohl
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Fredy Kurniawan
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Kayo Orellana
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
| | - Wei Zhang
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
- Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
- Characterization Facility, College of Science and Engineering, University of Minnesota, 100 Union Street S.E., Minneapolis, MN, 55455, USA
| | - Duane P Grandgenett
- Department of Molecular Microbiology and Immunology, Saint Louis University, 1100 S. Grand Boulevard, St. Louis, MO, 63104, USA
| | - Reuben S Harris
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA
- Howard Hughes Medical Institute, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA
| | - Anna C Sundborger-Lunna
- The Hormel Institute, University of Minnesota, 801 16th Avenue N.E., Austin, MN, 55912, USA.
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA.
| | - Hideki Aihara
- Masonic Cancer Center, University of Minnesota, 2231 6th Street S.E., Minneapolis, MN, 55455, USA.
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, 321 Church Street S.E., Minneapolis, MN, 55455, USA.
- Institute for Molecular Virology, University of Minnesota, 515 Delaware Street S.E., Minneapolis, MN, 55455, USA.
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19
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Barski MS, Minnell JJ, Maertens GN. Inhibition of HTLV-1 Infection by HIV-1 First- and Second-Generation Integrase Strand Transfer Inhibitors. Front Microbiol 2019; 10:1877. [PMID: 31474960 PMCID: PMC6705210 DOI: 10.3389/fmicb.2019.01877] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/30/2019] [Indexed: 12/21/2022] Open
Abstract
More than 10 million people worldwide are infected with the retrovirus human T-cell lymphotropic virus type 1 (HTLV-1). Infection phenotypes can range from asymptomatic to severe adult T-cell leukemia/lymphoma (ATLL) and HTLV-1-associated myelopathy. HTLV-1, like human immunodeficiency virus type 1 (HIV-1), is a blood-borne pathogen and viral infection happens in a similar fashion, with the major mode of transmission through breastfeeding. There is a strong correlation between time of infection and disease development, with a higher incidence of ATLL in patients infected during childhood. There is no successful therapeutic or preventative regimen for HTLV-1. It is therefore essential to develop therapies to inhibit transmission or block the onset/development of HTLV-1 associated diseases. Recently, we have seen the overwhelming success of integrase strand transfer inhibitors (INSTIs) in the treatment of HIV-1. Previously, raltegravir was shown to inhibit HTLV-1 infection. Here, we tested FDA-approved and two Phase II HIV-1 INSTIs in vitro and in a cell-to-cell infection model and show that they are highly active in blocking HTLV-1 infection, with bictegravir (EC50 = 0.30 ± 0.17 nM) performing best overall. INSTIs, in particular bictegravir, are more potent in blocking HTLV-1 transmission than tenofovir disproxil fumarate (TDF), an RT inhibitor. Our data suggest that HIV-1 INSTIs could present a good clinical strategy in HTLV-1 management and justifies the inclusion of INSTIs in clinical trials.
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Affiliation(s)
- Michał S Barski
- Division of Infectious Diseases, Section of Molecular Virology, Department of Medicine, St Mary's Hospital, Imperial College London, London, United Kingdom
| | - Jordan J Minnell
- Division of Infectious Diseases, Section of Molecular Virology, Department of Medicine, St Mary's Hospital, Imperial College London, London, United Kingdom
| | - Goedele N Maertens
- Division of Infectious Diseases, Section of Molecular Virology, Department of Medicine, St Mary's Hospital, Imperial College London, London, United Kingdom
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20
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Gallay K, Blot G, Chahpazoff M, Yajjou-Hamalian H, Confort MP, De Boisséson C, Leroux A, Luengo C, Fiorini F, Lavigne M, Chebloune Y, Gouet P, Moreau K, Blanchard Y, Ronfort C. In vitro, in cellulo and structural characterizations of the interaction between the integrase of Porcine Endogenous Retrovirus A/C and proteins of the BET family. Virology 2019; 532:69-81. [DOI: 10.1016/j.virol.2019.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 03/30/2019] [Accepted: 04/09/2019] [Indexed: 01/17/2023]
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21
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Bangham CRM, Matsuoka M. Human T-cell leukaemia virus type 1: parasitism and pathogenesis. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0272. [PMID: 28893939 PMCID: PMC5597739 DOI: 10.1098/rstb.2016.0272] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2017] [Indexed: 12/15/2022] Open
Abstract
Human T-cell leukaemia virus type 1 (HTLV-1) causes not only adult T-cell leukaemia-lymphoma (ATL), but also inflammatory diseases including HTLV-1-associated myelopathy/tropical spastic paraparesis. HTLV-1 transmits primarily through cell-to-cell contact, and generates abundant infected cells in the host in order to survive and transmit to a new host. The resulting high proviral load is closely associated with the development of ATL and inflammatory diseases. To increase the number of infected cells, HTLV-1 changes the immunophenotype of infected cells, induces proliferation and inhibits apoptosis through the cooperative actions of two viral genes, tax and HTLV-1 bZIP factor (HBZ). As a result, infected cells survive, proliferate and infiltrate into the tissues, which is critical for transmission of the virus. Thus, the strategy of this virus is indivisibly linked with its pathogenesis, providing a clue for prevention and treatment of HTLV-1-induced diseases. This article is part of the themed issue ‘Human oncogenic viruses’.
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Affiliation(s)
- Charles R M Bangham
- Division of Infectious Diseases, Faculty of Medicine, Imperial College London, London W2 1PG, UK
| | - Masao Matsuoka
- Department of Hematology, Rheumatology, and Infectious Diseases, Kumamoto University Faculty of Life Sciences, 1-1-1 Honjo, Kumamoto 860-8556, Japan .,Institute for Frontier Life and Medical Sciences, Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
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22
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Kulkarni A, Bangham CRM. HTLV-1: Regulating the Balance Between Proviral Latency and Reactivation. Front Microbiol 2018; 9:449. [PMID: 29615991 PMCID: PMC5867303 DOI: 10.3389/fmicb.2018.00449] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/27/2018] [Indexed: 12/26/2022] Open
Abstract
HTLV-1 plus-strand transcription begins with the production of doubly-spliced tax/rex transcripts, the levels of which are usually undetectable in freshly isolated peripheral blood mononuclear cells (PBMCs) from HTLV-1-infected individuals. However, the presence of a sustained chronically active cytotoxic T-cell response to HTLV-1 antigens in virtually all HTLV-1-infected individuals, regardless of their proviral load, argues against complete latency of the virus in vivo. There is an immediate burst of plus-strand transcription when blood from infected individuals is cultured ex vivo. How is the HTLV-1 plus strand silenced in PBMCs? Is it silenced in other anatomical compartments within the host? What reactivates the latent provirus in fresh PBMCs? While plus-strand transcription of the provirus appears to be intermittent, the minus-strand hbz transcripts are present in a majority of cells, albeit at low levels. What regulates the difference between the 5'- and 3'-LTR promoter activities and thereby the tax-hbz interplay? Finally, T lymphocytes are a migratory population of cells that encounter variable environments in different compartments of the body. Could these micro-environment changes influence the reactivation kinetics of the provirus? In this review we discuss the questions raised above, focusing on the early events leading to HTLV-1 reactivation from latency, and suggest future research directions.
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Affiliation(s)
- Anurag Kulkarni
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Imperial College London, London, United Kingdom
| | - Charles R M Bangham
- Section of Virology, Division of Infectious Diseases, Department of Medicine, Imperial College London, London, United Kingdom
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23
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Oliveira M, Lert-itthiporn W, Cavadas B, Fernandes V, Chuansumrit A, Anunciação O, Casademont I, Koeth F, Penova M, Tangnararatchakit K, Khor CC, Paul R, Malasit P, Matsuda F, Simon-Lorière E, Suriyaphol P, Pereira L, Sakuntabhai A. Joint ancestry and association test indicate two distinct pathogenic pathways involved in classical dengue fever and dengue shock syndrome. PLoS Negl Trop Dis 2018; 12:e0006202. [PMID: 29447178 PMCID: PMC5813895 DOI: 10.1371/journal.pntd.0006202] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 01/02/2018] [Indexed: 11/18/2022] Open
Abstract
Ethnic diversity has been long considered as one of the factors explaining why the severe forms of dengue are more prevalent in Southeast Asia than anywhere else. Here we take advantage of the admixed profile of Southeast Asians to perform coupled association-admixture analyses in Thai cohorts. For dengue shock syndrome (DSS), the significant haplotypes are located in genes coding for phospholipase C members (PLCB4 added to previously reported PLCE1), related to inflammation of blood vessels. For dengue fever (DF), we found evidence of significant association with CHST10, AHRR, PPP2R5E and GRIP1 genes, which participate in the xenobiotic metabolism signaling pathway. We conducted functional analyses for PPP2R5E, revealing by immunofluorescence imaging that the coded protein co-localizes with both DENV1 and DENV2 NS5 proteins. Interestingly, only DENV2-NS5 migrated to the nucleus, and a deletion of the predicted top-linking motif in NS5 abolished the nuclear transfer. These observations support the existence of differences between serotypes in their cellular dynamics, which may contribute to differential infection outcome risk. The contribution of the identified genes to the genetic risk render Southeast and Northeast Asian populations more susceptible to both phenotypes, while African populations are best protected against DSS and intermediately protected against DF, and Europeans the best protected against DF but the most susceptible against DSS.
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Affiliation(s)
- Marisa Oliveira
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
| | - Worachart Lert-itthiporn
- Bioinformatics and Data Management for Research, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Bruno Cavadas
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Verónica Fernandes
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
| | - Ampaiwan Chuansumrit
- Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Orlando Anunciação
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
| | - Isabelle Casademont
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
| | - Fanny Koeth
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
| | - Marina Penova
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kanchana Tangnararatchakit
- Department of Pediatrics, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Chiea Chuen Khor
- Genome Institute of Singapore, A-STAR, Singapore, Singapore
- Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Richard Paul
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
- CNRS, Unité de Recherche Associée 3012, Paris, France
| | - Prida Malasit
- Dengue Hemorrhagic Fever Research Unit, Office for Research and Development, Siriraj Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
- Medical Biotechnology Unit, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand
| | - Fumihiko Matsuda
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Etienne Simon-Lorière
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
- CNRS, Unité de Recherche Associée 3012, Paris, France
| | - Prapat Suriyaphol
- Bioinformatics and Data Management for Research, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Luisa Pereira
- i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Department of Pathology, Faculty of Medicine, University of Porto, Porto, Portugal
- * E-mail: (LP); (AS)
| | - Anavaj Sakuntabhai
- Functional Genetics of Infectious Diseases Unit, Institut Pasteur, Paris, France
- Pasteur Kyoto International Joint Research Unit for Integrative Vaccinomics, Kyoto, Japan
- CNRS, Unité de Recherche Associée 3012, Paris, France
- * E-mail: (LP); (AS)
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24
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Stockum A, Snijders AP, Maertens GN. USP11 deubiquitinates RAE1 and plays a key role in bipolar spindle formation. PLoS One 2018; 13:e0190513. [PMID: 29293652 PMCID: PMC5749825 DOI: 10.1371/journal.pone.0190513] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 12/15/2017] [Indexed: 11/26/2022] Open
Abstract
Correct segregation of the mitotic chromosomes into daughter cells is a highly regulated process critical to safeguard genome stability. During M phase the spindle assembly checkpoint (SAC) ensures that all kinetochores are correctly attached before its inactivation allows progression into anaphase. Upon SAC inactivation, the anaphase promoting complex/cyclosome (APC/C) E3 ligase ubiquitinates and targets cyclin B and securin for proteasomal degradation. Here, we describe the identification of Ribonucleic Acid Export protein 1 (RAE1), a protein previously shown to be involved in SAC regulation and bipolar spindle formation, as a novel substrate of the deubiquitinating enzyme (DUB) Ubiquitin Specific Protease 11 (USP11). Lentiviral knock-down of USP11 or RAE1 in U2OS cells drastically reduces cell proliferation and increases multipolar spindle formation. We show that USP11 is associated with the mitotic spindle, does not regulate SAC inactivation, but controls ubiquitination of RAE1 at the mitotic spindle, hereby functionally modulating its interaction with Nuclear Mitotic Apparatus protein (NuMA).
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Affiliation(s)
- Anna Stockum
- Imperial College London, Department of Medicine, Division of Infectious Diseases, Norfolk Place, London, United Kingdom
| | - Ambrosius P. Snijders
- Francis Crick Institute, The Crick Mass Spectrometry Science Technology Platform, 1 Midland Road, London, United Kingdom
| | - Goedele N. Maertens
- Imperial College London, Department of Medicine, Division of Infectious Diseases, Norfolk Place, London, United Kingdom
- * E-mail:
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25
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Kruse T, Biedenkopf N, Hertz EPT, Dietzel E, Stalmann G, López-Méndez B, Davey NE, Nilsson J, Becker S. The Ebola Virus Nucleoprotein Recruits the Host PP2A-B56 Phosphatase to Activate Transcriptional Support Activity of VP30. Mol Cell 2017; 69:136-145.e6. [PMID: 29290611 DOI: 10.1016/j.molcel.2017.11.034] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/01/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
Abstract
Transcription of the Ebola virus genome depends on the viral transcription factor VP30 in its unphosphorylated form, but the underlying molecular mechanism of VP30 dephosphorylation is unknown. Here we show that the Ebola virus nucleoprotein (NP) recruits the host PP2A-B56 protein phosphatase through a B56-binding LxxIxE motif and that this motif is essential for VP30 dephosphorylation and viral transcription. The LxxIxE motif and the binding site of VP30 in NP are in close proximity, and both binding sites are required for the dephosphorylation of VP30. We generate a specific inhibitor of PP2A-B56 and show that it suppresses Ebola virus transcription and infection. This work dissects the molecular mechanism of VP30 dephosphorylation by PP2A-B56, and it pinpoints this phosphatase as a potential target for therapeutic intervention.
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Affiliation(s)
- Thomas Kruse
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Nadine Biedenkopf
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Emil Peter Thrane Hertz
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Erik Dietzel
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Gertrud Stalmann
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany
| | - Blanca López-Méndez
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark
| | - Norman E Davey
- Conway Institute of Biomolecular and Biomedical Sciences, University College Dublin, Dublin 4, Ireland
| | - Jakob Nilsson
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, Denmark.
| | - Stephan Becker
- Institute of Virology, Philipps Universität Marburg, Marburg, Germany; German Center of Infection Research (DZIF), Giessen-Marburg-Langen, Marburg, Germany.
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26
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Abstract
Human T cell leukemia virus type 1 (HTLV-1), also known as human T lymphotropic virus type 1, was the first exogenous human retrovirus discovered. Unlike the distantly related lentivirus HIV-1, HTLV-1 causes disease in only 5-10% of infected people, depending on their ethnic origin. But whereas HIV-1 infection and the consequent diseases can be efficiently contained in most cases by antiretroviral drug treatment, there is no satisfactory treatment for the malignant or inflammatory diseases caused by HTLV-1. The purpose of the present article is to review recent advances in the understanding of the mechanisms by which the virus persists in vivo and causes disabling or fatal diseases.
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Affiliation(s)
- Charles R M Bangham
- Division of Infectious Diseases, Faculty of Medicine, Imperial College, London W2 1PG, United Kingdom;
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27
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Cook L, Melamed A, Yaguchi H, Bangham CR. The impact of HTLV-1 on the cellular genome. Curr Opin Virol 2017; 26:125-131. [PMID: 28822906 DOI: 10.1016/j.coviro.2017.07.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/12/2017] [Accepted: 07/18/2017] [Indexed: 10/19/2022]
Abstract
Human T-lymphotropic virus type-1 (HTLV-1) is the causative agent of adult T-cell leukaemia/lymphoma (ATL), an aggressive CD4+ T-cell malignancy. The mechanisms of leukaemogenesis in ATL are incompletely understood. Insertional mutagenesis has not previously been thought to contribute to the pathogenesis of ATL. However, the recent discovery that HTLV-1 binds the key chromatin architectural protein CTCF raises the hypothesis that HTLV-1 deregulates host gene expression by causing abnormal chromatin looping, bringing the strong HTLV-1 promoter-enhancer near to host genes that lie up to 2Mb from the integrated provirus. Here we review current opinion on the mechanisms of oncogenesis in ATL, with particular emphasis on the local and distant impact of HTLV-1 on the structure and expression of the host genome.
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Affiliation(s)
- Lucy Cook
- Section of Virology, Imperial College London, Norfolk Place, London W2 1PG, United Kingdom; National Centre for Human Retrovirology, Imperial College Healthcare NHS Trust, London, United Kingdom; Department of Haematology, Imperial College Healthcare NHS Trust, United Kingdom
| | - Anat Melamed
- Section of Virology, Imperial College London, Norfolk Place, London W2 1PG, United Kingdom
| | - Hiroko Yaguchi
- Section of Virology, Imperial College London, Norfolk Place, London W2 1PG, United Kingdom
| | - Charles Rm Bangham
- Section of Virology, Imperial College London, Norfolk Place, London W2 1PG, United Kingdom.
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28
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The FACT Complex Promotes Avian Leukosis Virus DNA Integration. J Virol 2017; 91:JVI.00082-17. [PMID: 28122976 DOI: 10.1128/jvi.00082-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 01/17/2017] [Indexed: 12/25/2022] Open
Abstract
All retroviruses need to integrate a DNA copy of their genome into the host chromatin. Cellular proteins regulating and targeting lentiviral and gammaretroviral integration in infected cells have been discovered, but the factors that mediate alpharetroviral avian leukosis virus (ALV) integration are unknown. In this study, we have identified the FACT protein complex, which consists of SSRP1 and Spt16, as a principal cellular binding partner of ALV integrase (IN). Biochemical experiments with purified recombinant proteins show that SSRP1 and Spt16 are able to individually bind ALV IN, but only the FACT complex effectively stimulates ALV integration activity in vitro Likewise, in infected cells, the FACT complex promotes ALV integration activity, with proviral integration frequency varying directly with cellular expression levels of the FACT complex. An increase in 2-long-terminal-repeat (2-LTR) circles in the depleted FACT complex cell line indicates that this complex regulates the ALV life cycle at the level of integration. This regulation is shown to be specific to ALV, as disruption of the FACT complex did not inhibit either lentiviral or gammaretroviral integration in infected cells.IMPORTANCE The majority of human gene therapy approaches utilize HIV-1- or murine leukemia virus (MLV)-based vectors, which preferentially integrate near genes and regulatory regions; thus, insertional mutagenesis is a substantial risk. In contrast, ALV integrates more randomly throughout the genome, which decreases the risks of deleterious integration. Understanding how ALV integration is regulated could facilitate the development of ALV-based vectors for use in human gene therapy. Here we show that the FACT complex directly binds and regulates ALV integration efficiency in vitro and in infected cells.
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29
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Hertz EPT, Kruse T, Davey NE, López-Méndez B, Sigurðsson JO, Montoya G, Olsen JV, Nilsson J. A Conserved Motif Provides Binding Specificity to the PP2A-B56 Phosphatase. Mol Cell 2016; 63:686-695. [PMID: 27453045 DOI: 10.1016/j.molcel.2016.06.024] [Citation(s) in RCA: 187] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 06/05/2016] [Accepted: 06/15/2016] [Indexed: 01/17/2023]
Abstract
Dynamic protein phosphorylation is a fundamental mechanism regulating biological processes in all organisms. Protein phosphatase 2A (PP2A) is the main source of phosphatase activity in the cell, but the molecular details of substrate recognition are unknown. Here, we report that a conserved surface-exposed pocket on PP2A regulatory B56 subunits binds to a consensus sequence on interacting proteins, which we term the LxxIxE motif. The composition of the motif modulates the affinity for B56, which in turn determines the phosphorylation status of associated substrates. Phosphorylation of amino acid residues within the motif increases B56 binding, allowing integration of kinase and phosphatase activity. We identify conserved LxxIxE motifs in essential proteins throughout the eukaryotic domain of life and in human viruses, suggesting that the motifs are required for basic cellular function. Our study provides a molecular description of PP2A binding specificity with broad implications for understanding signaling in eukaryotes.
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Affiliation(s)
- Emil Peter Thrane Hertz
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Thomas Kruse
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
| | - Norman E Davey
- Conway Institute of Biomolecular and Biomedical Sciences, University College Dublin, Dublin 4, Ireland
| | - Blanca López-Méndez
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Jón Otti Sigurðsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Guillermo Montoya
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Jesper V Olsen
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Jakob Nilsson
- Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
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30
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Abstract
The integration of a DNA copy of the viral RNA genome into host chromatin is the defining step of retroviral replication. This enzymatic process is catalyzed by the virus-encoded integrase protein, which is conserved among retroviruses and LTR-retrotransposons. Retroviral integration proceeds via two integrase activities: 3'-processing of the viral DNA ends, followed by the strand transfer of the processed ends into host cell chromosomal DNA. Herein we review the molecular mechanism of retroviral DNA integration, with an emphasis on reaction chemistries and architectures of the nucleoprotein complexes involved. We additionally discuss the latest advances on anti-integrase drug development for the treatment of AIDS and the utility of integrating retroviral vectors in gene therapy applications.
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Affiliation(s)
- Paul Lesbats
- Clare Hall Laboratories, The Francis Crick Institute , Blanche Lane, South Mimms, EN6 3LD, U.K
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute and Department of Medicine, Harvard Medical School , 450 Brookline Avenue, Boston, Massachusetts 02215 United States
| | - Peter Cherepanov
- Clare Hall Laboratories, The Francis Crick Institute , Blanche Lane, South Mimms, EN6 3LD, U.K.,Imperial College London , St-Mary's Campus, Norfolk Place, London, W2 1PG, U.K
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