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Kmiec D, Kirchhoff F. Antiviral factors and their counteraction by HIV-1: many uncovered and more to be discovered. J Mol Cell Biol 2024; 16:mjae005. [PMID: 38318650 PMCID: PMC11334937 DOI: 10.1093/jmcb/mjae005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 12/13/2023] [Accepted: 02/04/2024] [Indexed: 02/07/2024] Open
Abstract
Extensive studies on HIV-1 have led to the discovery of a variety of structurally and functionally diverse innate defense factors that target various steps of the retroviral replication cycle. Some of them, such as APOBEC3, tetherin, and SERINC5, are well established. Their importance is evident from the fact that HIV-1 uses its accessory proteins Vif, Vpu, and Nef to counteract them. However, the list of antiviral factors is constantly increasing, and accumulating evidence suggests that innate defense mechanisms, which restrict HIV-1 and/or are counteracted by viral proteins, remain to be discovered. These antiviral factors are relevant to diseases other than HIV/AIDS, since they are commonly active against various viral pathogens. In this review, we provide an overview of recently reported antiretroviral factors and viral countermeasures, present the evidence suggesting that more innate defense mechanisms remain to be discovered, and discuss why this is a challenging but rewarding task.
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Affiliation(s)
- Dorota Kmiec
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
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2
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Legrand A, Dahoui C, De La Myre Mory C, Noy K, Guiguettaz L, Versapuech M, Loyer C, Pillon M, Wcislo M, Guéguen L, Berlioz-Torrent C, Cimarelli A, Mateo M, Fiorini F, Ricci EP, Etienne L. SAMD9L acts as an antiviral factor against HIV-1 and primate lentiviruses by restricting viral and cellular translation. PLoS Biol 2024; 22:e3002696. [PMID: 38959200 PMCID: PMC11221667 DOI: 10.1371/journal.pbio.3002696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 05/31/2024] [Indexed: 07/05/2024] Open
Abstract
Sterile alpha motif domain-containing proteins 9 and 9-like (SAMD9/9L) are associated with life-threatening genetic diseases in humans and are restriction factors of poxviruses. Yet, their cellular function and the extent of their antiviral role are poorly known. Here, we found that interferon-stimulated human SAMD9L restricts HIV-1 in the late phases of replication, at the posttranscriptional and prematuration steps, impacting viral translation and, possibly, endosomal trafficking. Surprisingly, the paralog SAMD9 exerted an opposite effect, enhancing HIV-1. More broadly, we showed that SAMD9L restricts primate lentiviruses, but not a gammaretrovirus (MLV), nor 2 RNA viruses (arenavirus MOPV and rhabdovirus VSV). Using structural modeling and mutagenesis of SAMD9L, we identified a conserved Schlafen-like active site necessary for HIV-1 restriction by human and a rodent SAMD9L. By testing a gain-of-function constitutively active variant from patients with SAMD9L-associated autoinflammatory disease, we determined that SAMD9L pathogenic functions also depend on the Schlafen-like active site. Finally, we found that the constitutively active SAMD9L strongly inhibited HIV, MLV, and, to a lesser extent, MOPV. This suggests that the virus-specific effect of SAMD9L may involve its differential activation/sensing and the virus ability to evade from SAMD9L restriction. Overall, our study identifies SAMD9L as an HIV-1 antiviral factor from the cell autonomous immunity and deciphers host determinants underlying the translational repression. This provides novel links and therapeutic avenues against viral infections and genetic diseases.
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Affiliation(s)
- Alexandre Legrand
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Clara Dahoui
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Clément De La Myre Mory
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Kodie Noy
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
- Unité de Biologie des Infections Virales Émergentes, Institut Pasteur, Lyon, Université Paris Cité, Paris, France
| | - Laura Guiguettaz
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), Université de Lyon, INSERM U1293, CNRS UMR 5239, ENS de Lyon, UCBL1, Lyon, France
| | - Margaux Versapuech
- Université Paris Cité, CNRS, Inserm, Institut Cochin, INSERM, CNRS, Paris, France
| | - Clara Loyer
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Margaux Pillon
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Mégane Wcislo
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Laurent Guéguen
- Laboratoire de Biologie et Biométrie Évolutive (LBBE), CNRS UMR 5558, UCBL1, Villeurbanne, France
| | | | - Andrea Cimarelli
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
| | - Mathieu Mateo
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
- Unité de Biologie des Infections Virales Émergentes, Institut Pasteur, Lyon, Université Paris Cité, Paris, France
| | - Francesca Fiorini
- Retroviruses and structural biochemistry, Molecular Microbiology and Structural Biochemistry (MMSB), IBCP, CNRS UMR 5086, University of Lyon, Lyon, France
| | - Emiliano P. Ricci
- Laboratoire de Biologie et Modélisation de la Cellule (LBMC), Université de Lyon, INSERM U1293, CNRS UMR 5239, ENS de Lyon, UCBL1, Lyon, France
| | - Lucie Etienne
- Centre International de Recherche en Infectiologie (CIRI), Inserm U1111, UCBL1, CNRS UMR 5308, ENS de Lyon, Université de Lyon, Lyon, France
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3
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Yapo V, Majumder K, Tedbury PR, Wen X, Ong YT, Johnson MC, Sarafianos SG. HIV-2 inhibits HIV-1 gene expression via two independent mechanisms during cellular co-infection. J Virol 2023; 97:e0187022. [PMID: 37991365 PMCID: PMC10734542 DOI: 10.1128/jvi.01870-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 06/28/2023] [Indexed: 11/23/2023] Open
Abstract
IMPORTANCE Twenty-five years after the first report that HIV-2 infection can reduce HIV-1-associated pathogenesis in dual-infected patients, the mechanisms are still not well understood. We explored these mechanisms in cell culture and showed first that these viruses can co-infect individual cells. Under specific conditions, HIV-2 inhibits HIV-1 through two distinct mechanisms, a broad-spectrum interferon response and an HIV-1-specific inhibition conferred by the HIV-2 TAR. The former could play a prominent role in dually infected individuals, whereas the latter targets HIV-1 promoter activity through competition for HIV-1 Tat binding when the same target cell is dually infected. That mechanism suppresses HIV-1 transcription by stalling RNA polymerase II complexes at the promoter through a minimal inhibitory region within the HIV-2 TAR. This work delineates the sequence of appearance and the modus operandi of each mechanism.
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Affiliation(s)
- Vincent Yapo
- CS Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri, USA
| | - Kinjal Majumder
- CS Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri, USA
| | - Philip R. Tedbury
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Xin Wen
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Yee T. Ong
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Marc C. Johnson
- CS Bond Life Sciences Center, University of Missouri, Columbia, Missouri, USA
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, Missouri, USA
| | - Stefan G. Sarafianos
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
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4
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Abstract
Human and simian immunodeficiency viruses (HIVs and SIVs, respectively) encode several small proteins (Vif, Vpr, Nef, Vpu, and Vpx) that are called accessory because they are not generally required for viral replication in cell culture. However, they play complex and important roles for viral immune evasion and spread in vivo. Here, we discuss the diverse functions and the relevance of the viral protein U (Vpu) that is expressed from a bicistronic RNA during the late stage of the viral replication cycle and found only in HIV-1 and closely related SIVs. It is well established that Vpu counteracts the restriction factor tetherin, mediates degradation of the primary viral CD4 receptors, and inhibits activation of the transcription factor nuclear factor kappa B. Recent studies identified additional activities and provided new insights into the sophisticated mechanisms by which Vpu enhances and prolongs the release of fully infectious viral particles. In addition, it has been shown that Vpu prevents superinfection not only by degrading CD4 but also by modulating DNA repair mechanisms to promote degradation of nuclear viral complementary DNA in cells that are already productively infected.
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Affiliation(s)
- Meta Volcic
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany;
| | - Lisa Wiesmüller
- Division of Gynecological Oncology, Department of Obstetrics and Gynecology, Ulm University Medical Center, Ulm, Germany
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany;
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5
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Kulsuptrakul J, Turcotte EA, Emerman M, Mitchell PS. A human-specific motif facilitates CARD8 inflammasome activation after HIV-1 infection. eLife 2023; 12:e84108. [PMID: 37417868 PMCID: PMC10359095 DOI: 10.7554/elife.84108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 07/06/2023] [Indexed: 07/08/2023] Open
Abstract
Inflammasomes are cytosolic innate immune complexes that assemble upon detection of diverse pathogen-associated cues and play a critical role in host defense and inflammatory pathogenesis. Here, we find that the human inflammasome-forming sensor CARD8 senses HIV-1 infection via site-specific cleavage of the CARD8 N-terminus by the HIV protease (HIV-1PR). HIV-1PR cleavage of CARD8 induces pyroptotic cell death and the release of pro-inflammatory cytokines from infected cells, processes regulated by Toll-like receptor stimulation prior to viral infection. In acutely infected cells, CARD8 senses the activity of both de novo translated HIV-1PR and packaged HIV-1PR that is released from the incoming virion. Moreover, our evolutionary analyses reveal that the HIV-1PR cleavage site in human CARD8 arose after the divergence of chimpanzees and humans. Although chimpanzee CARD8 does not recognize proteases from HIV or simian immunodeficiency viruses from chimpanzees (SIVcpz), SIVcpz does cleave human CARD8, suggesting that SIVcpz was poised to activate the human CARD8 inflammasome prior to its cross-species transmission into humans. Our findings suggest a unique role for CARD8 inflammasome activation in response to lentiviral infection of humans.
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Affiliation(s)
- Jessie Kulsuptrakul
- Molecular and Cellular Biology Graduate Program, University of WashingtonSeattleUnited States
| | - Elizabeth A Turcotte
- Division of Immunology and Pathogenesis, University of California, BerkeleyBerkeleyUnited States
| | - Michael Emerman
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer CenterSeattleUnited States
| | - Patrick S Mitchell
- Department of Microbiology, University of WashingtonSeattleUnited States
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6
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Li YL, Langley CA, Azumaya CM, Echeverria I, Chesarino NM, Emerman M, Cheng Y, Gross JD. The structural basis for HIV-1 Vif antagonism of human APOBEC3G. Nature 2023; 615:728-733. [PMID: 36754086 PMCID: PMC10033410 DOI: 10.1038/s41586-023-05779-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 02/02/2023] [Indexed: 02/10/2023]
Abstract
The APOBEC3 (A3) proteins are host antiviral cellular proteins that hypermutate the viral genome of diverse viral families. In retroviruses, this process requires A3 packaging into viral particles1-4. The lentiviruses encode a protein, Vif, that antagonizes A3 family members by targeting them for degradation. Diversification of A3 allows host escape from Vif whereas adaptations in Vif enable cross-species transmission of primate lentiviruses. How this 'molecular arms race' plays out at the structural level is unknown. Here, we report the cryogenic electron microscopy structure of human APOBEC3G (A3G) bound to HIV-1 Vif, and the hijacked cellular proteins that promote ubiquitin-mediated proteolysis. A small surface explains the molecular arms race, including a cross-species transmission event that led to the birth of HIV-1. Unexpectedly, we find that RNA is a molecular glue for the Vif-A3G interaction, enabling Vif to repress A3G by ubiquitin-dependent and -independent mechanisms. Our results suggest a model in which Vif antagonizes A3G by intercepting it in its most dangerous form for the virus-when bound to RNA and on the pathway to packaging-to prevent viral restriction. By engaging essential surfaces required for restriction, Vif exploits a vulnerability in A3G, suggesting a general mechanism by which RNA binding helps to position key residues necessary for viral antagonism of a host antiviral gene.
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Affiliation(s)
- Yen-Li Li
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Caroline A Langley
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Center, Seattle, WA, USA
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA, USA
| | - Caleigh M Azumaya
- Fred Hutchinson Cancer Center, Electron Microscopy Shared Resource, Seattle, WA, USA
| | - Ignacia Echeverria
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA
- Quantitative Bioscience Institute, University of California, San Francisco, CA, USA
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Nicholas M Chesarino
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Michael Emerman
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Yifan Cheng
- Quantitative Bioscience Institute, University of California, San Francisco, CA, USA
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, USA
- Howard Hughes Medical Institute, University of California, San Francisco, CA, USA
| | - John D Gross
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA.
- Quantitative Bioscience Institute, University of California, San Francisco, CA, USA.
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7
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Rochman ND, Wolf YI, Koonin EV. Molecular adaptations during viral epidemics. EMBO Rep 2022; 23:e55393. [PMID: 35848484 PMCID: PMC9346483 DOI: 10.15252/embr.202255393] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 06/18/2022] [Accepted: 06/27/2022] [Indexed: 07/20/2023] Open
Abstract
In 1977, the world witnessed both the eradication of smallpox and the beginning of the modern age of genomics. Over the following half-century, 7 epidemic viruses of international concern galvanized virologists across the globe and led to increasingly extensive virus genome sequencing. These sequencing efforts exerted over periods of rapid adaptation of viruses to new hosts, in particular, humans provide insight into the molecular mechanisms underpinning virus evolution. Investment in virus genome sequencing was dramatically increased by the unprecedented support for phylogenomic analyses during the COVID-19 pandemic. In this review, we attempt to piece together comprehensive molecular histories of the adaptation of variola virus, HIV-1 M, SARS, H1N1-SIV, MERS, Ebola, Zika, and SARS-CoV-2 to the human host. Disruption of genes involved in virus-host interaction in animal hosts, recombination including genome segment reassortment, and adaptive mutations leading to amino acid replacements in virus proteins involved in host receptor binding and membrane fusion are identified as the key factors in the evolution of epidemic viruses.
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Affiliation(s)
- Nash D Rochman
- National Center for Biotechnology InformationNational Library of MedicineBethesdaMDUSA
| | - Yuri I Wolf
- National Center for Biotechnology InformationNational Library of MedicineBethesdaMDUSA
| | - Eugene V Koonin
- National Center for Biotechnology InformationNational Library of MedicineBethesdaMDUSA
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8
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Greiner D, Scott TM, Olson GS, Aderem A, Roh-Johnson M, Johnson JS. Genetic Modification of Primary Human Myeloid Cells to Study Cell Migration, Activation, and Organelle Dynamics. Curr Protoc 2022; 2:e514. [PMID: 36018279 PMCID: PMC9476234 DOI: 10.1002/cpz1.514] [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] [Indexed: 06/15/2023]
Abstract
Myeloid dendritic cells (DCs) and macrophages are mononuclear phagocytes with key roles in the immune system. As antigen-presenting cells, they link innate detection of microbes with programming adaptive immune responses. Myeloid DCs and macrophages also play critical roles in development, promote tissue homeostasis, and direct repair in response to injury and inflammation. As cellular migration and organelle dynamics are intimately connected with these processes, it is necessary to develop tools to track myeloid cell behavior and function. Here, we build on previously established protocols to isolate primary human myeloid cells from peripheral blood and report an optimized method for their genetic modification with lentiviral vectors to study processes related to cell migration, activation, and organelle dynamics. Specifically, we provide a protocol for delivering genetically encoded fluorescent markers into primary monocyte-derived DCs (MDDCs) and monocyte-derived macrophages (MDMs) to label mitochondria, peroxisomes, and whole cells. We describe the isolation of primary CD14+ monocytes from peripheral blood using positive selection with magnetic beads and, alternatively, isolation based on plastic adherence. Isolated CD14+ cells can be transduced with lentiviral vectors and subsequently cultured in the presence of cytokines to derive MDDCs or MDMs. This protocol is highly adaptable for cotransduction with vectors to knock down or overexpress genes of interest. These tools enable mechanistic studies of genetically modified myeloid cells through flow cytometry, fluorescence microscopy, and other downstream assays. © 2022 Wiley Periodicals LLC. Basic Protocol: Transduction of MDDCs and MDMs with lentiviral vectors encoding fluorescent markers Alternate Protocol 1: Isolation of monocytes by plastic adhesion Alternate Protocol 2: Transduction of MDDCs and MDMs with lentiviral vectors to knock down or overexpress genes of interest Support Protocol 1: Production and purification of lentiviral vectors for transduction into primary human myeloid cells Support Protocol 2: Flow cytometry of MDDCs and MDMs Support Protocol 3: Fixed and live-cell imaging of fluorescent markers in MDMs and MDDCs.
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Affiliation(s)
- Daniel Greiner
- Department of Biochemistry, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
| | - Tiana M. Scott
- Department of Pathology, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
- Division of Microbiology and Immunology, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
| | - Gregory S. Olson
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, USA
- Medical Scientist Training Program, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Alan Aderem
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, WA 98109, USA
| | - Minna Roh-Johnson
- Department of Biochemistry, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
| | - Jarrod S. Johnson
- Department of Pathology, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
- Division of Microbiology and Immunology, University of Utah School of Medicine; Salt Lake City, UT, 84112, USA
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9
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Bowen NE, Oo A, Kim B. Mechanistic Interplay between HIV-1 Reverse Transcriptase Enzyme Kinetics and Host SAMHD1 Protein: Viral Myeloid-Cell Tropism and Genomic Mutagenesis. Viruses 2022; 14:v14081622. [PMID: 35893688 PMCID: PMC9331428 DOI: 10.3390/v14081622] [Citation(s) in RCA: 4] [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: 06/20/2022] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 11/23/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) has been the primary interest among studies on antiviral discovery, viral replication kinetics, drug resistance, and viral evolution. Following infection and entry into target cells, the HIV-1 core disassembles, and the viral RT concomitantly converts the viral RNA into double-stranded proviral DNA, which is integrated into the host genome. The successful completion of the viral life cycle highly depends on the enzymatic DNA polymerase activity of RT. Furthermore, HIV-1 RT has long been known as an error-prone DNA polymerase due to its lack of proofreading exonuclease properties. Indeed, the low fidelity of HIV-1 RT has been considered as one of the key factors in the uniquely high rate of mutagenesis of HIV-1, which leads to efficient viral escape from immune and therapeutic antiviral selective pressures. Interestingly, a series of studies on the replication kinetics of HIV-1 in non-dividing myeloid cells and myeloid specific host restriction factor, SAM domain, and HD domain-containing protein, SAMHD1, suggest that the myeloid cell tropism and high rate of mutagenesis of HIV-1 are mechanistically connected. Here, we review not only HIV-1 RT as a key antiviral target, but also potential evolutionary and mechanistic crosstalk among the unique enzymatic features of HIV-1 RT, the replication kinetics of HIV-1, cell tropism, viral genetic mutation, and host SAMHD1 protein.
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Affiliation(s)
- Nicole E. Bowen
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA 30329, USA; (N.E.B.); (A.O.)
| | - Adrian Oo
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA 30329, USA; (N.E.B.); (A.O.)
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA 30329, USA; (N.E.B.); (A.O.)
- Center for Drug Discovery, Children’s Healthcare of Atlanta, Atlanta, GA 30329, USA
- Correspondence:
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10
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HIV-1 Vif gained breadth in APOBEC3G specificity after cross-species transmission of its precursors. J Virol 2021; 96:e0207121. [PMID: 34908448 DOI: 10.1128/jvi.02071-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
APOBEC3G (A3G) is a host-encoded cytidine deaminase that potently restricts retroviruses, such as HIV-1, and depends on its ability to package into virions. As a consequence of this, HIV-1 protein Vif has evolved to antagonize human A3G by targeting it for ubiquitination and subsequent degradation. There is an ancient arms-race between Vif and A3G highlighted by amino acids 128 and 130 in A3G that have evolved under positive selection due to Vif-mediated selective pressure in Old World primates. Nonetheless, not all possible amino acid combinations at these sites have been sampled by nature and it is not clear the evolutionary potential of species to resist Vif antagonism. To explore the evolutionary space of positively selected sites in the Vif-binding region of A3G, we designed a combinatorial mutagenesis screen to introduce all 20 amino acids at sites 128 and 130. Our screen uncovered mutants of A3G with several interesting phenotypes, including loss of antiviral activity and resistance of Vif antagonism. However, HIV-1 Vif exhibited remarkable flexibility in antagonizing A3G 128 and 130 mutants, which significantly reduces viable Vif resistance strategies for hominid primates. Importantly, we find that broadened Vif specificity was conferred through Loop 5 adaptations that were required for cross-species adaptation from Old World monkey A3G to hominid A3G. Our evidence suggests that Vif adaptation to novel A3G interfaces during cross-species transmission may train Vif towards broadened specificity that can further facilitate cross-species transmissions and raise the barrier to host resistance. Importance APOBEC3G (A3G) is an antiviral protein that potently restricts retroviruses like HIV. In turn, the HIV-1 protein Vif has evolved to antagonize A3G through degradation. Two rapidly evolving sites in A3G confer resistance to unadapted Vif and act as a barrier to cross-species transmission of retroviruses. We recently identified a single amino acid mutation in an SIV Vif that contributed to the cross-species origins of SIV infecting chimpanzee, and ultimately the HIV-1 pandemic. This mutation broadened specificity of this Vif to both antagonize the A3G of its host while simultaneously overcoming the A3G barrier in the great apes. In this work, we explore the evolutionary space of human A3G at these rapidly evolving sites to understand if the broadened Vif specificity gained during cross-species transmission confers an advantage to HIV-1 Vif in its host-virus arms race with A3G.
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11
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Gaba A, Hix MA, Suhail S, Flath B, Boysan B, Williams DR, Pelletier T, Emerman M, Morcos F, Cisneros GA, Chelico L. Divergence in Dimerization and Activity of Primate APOBEC3C. J Mol Biol 2021; 433:167306. [PMID: 34666043 PMCID: PMC9202443 DOI: 10.1016/j.jmb.2021.167306] [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: 08/22/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 11/21/2022]
Abstract
The APOBEC3 (A3) family of single-stranded DNA cytidine deaminases are host restriction factors that inhibit lentiviruses, such as HIV-1, in the absence of the Vif protein that causes their degradation. Deamination of cytidine in HIV-1 (−)DNA forms uracil that causes inactivating mutations when uracil is used as a template for (+)DNA synthesis. For APOBEC3C (A3C), the chimpanzee and gorilla orthologues are more active than human A3C, and we determined that Old World Monkey A3C from rhesus macaque (rh) is not active against HIV-1. Biochemical, virological, and coevolutionary analyses combined with molecular dynamics simulations showed that the key amino acids needed to promote rhA3C antiviral activity, 44, 45, and 144, also promoted dimerization and changes to the dynamics of loop 1, near the enzyme active site. Although forced evolution of rhA3C resulted in a similar dimer interface with hominid A3C, the key amino acid contacts were different. Overall, our results determine the basis for why rhA3C is less active than human A3C and establish the amino acid network for dimerization and increased activity. Based on identification of the key amino acids determining Old World Monkey antiviral activity we predict that other Old World Monkey A3Cs did not impart anti-lentiviral activity, despite fixation of a key residue needed for hominid A3C activity. Overall, the coevolutionary analysis of the A3C dimerization interface presented also provides a basis from which to analyze dimerization interfaces of other A3 family members.
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Affiliation(s)
- Amit Gaba
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada. https://twitter.com/optimist1023
| | - Mark A Hix
- Department of Chemistry, University of North Texas, Denton, TX, USA. https://twitter.com/markahix
| | - Sana Suhail
- Department of Biological Sciences, Center for Systems Biology, University of Texas at Dallas, Richardson, TX, USA. https://twitter.com/sakuraa_329
| | - Ben Flath
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Brock Boysan
- Department of Chemistry, University of North Texas, Denton, TX, USA
| | - Danielle R Williams
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. https://twitter.com/dani_renee_
| | - Tomas Pelletier
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Michael Emerman
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. https://twitter.com/memerman
| | - Faruck Morcos
- Department of Biological Sciences, Center for Systems Biology, University of Texas at Dallas, Richardson, TX, USA; Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA. https://twitter.com/MorcosLab
| | - G Andrés Cisneros
- Department of Chemistry, University of North Texas, Denton, TX, USA. https://twitter.com/CisnerosRes
| | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
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12
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Martin MM, Matkovic R, Larrous P, Morel M, Lasserre A, Vauthier V, Margottin-Goguet F. Binding to DCAF1 distinguishes TASOR and SAMHD1 degradation by HIV-2 Vpx. PLoS Pathog 2021; 17:e1009609. [PMID: 34699574 PMCID: PMC8570500 DOI: 10.1371/journal.ppat.1009609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 11/05/2021] [Accepted: 10/15/2021] [Indexed: 01/18/2023] Open
Abstract
Human Immunodeficiency viruses type 1 and 2 (HIV-1 and HIV-2) succeed to evade host immune defenses by using their viral auxiliary proteins to antagonize host restriction factors. HIV-2/SIVsmm Vpx is known for degrading SAMHD1, a factor impeding the reverse transcription. More recently, Vpx was also shown to counteract HUSH, a complex constituted of TASOR, MPP8 and periphilin, which blocks viral expression from the integrated viral DNA. In a classical ubiquitin ligase hijacking model, Vpx bridges the DCAF1 ubiquitin ligase substrate adaptor to SAMHD1, for subsequent ubiquitination and degradation. Here, we investigated whether the same mechanism is at stake for Vpx-mediated HUSH degradation. While we confirm that Vpx bridges SAMHD1 to DCAF1, we show that TASOR can interact with DCAF1 in the absence of Vpx. Nonetheless, this association was stabilized in the presence of Vpx, suggesting the existence of a ternary complex. The N-terminal PARP-like domain of TASOR is involved in DCAF1 binding, but not in Vpx binding. We also characterized a series of HIV-2 Vpx point mutants impaired in TASOR degradation, while still degrading SAMHD1. Vpx mutants ability to degrade TASOR correlated with their capacity to enhance HIV-1 minigenome expression as expected. Strikingly, several Vpx mutants impaired for TASOR degradation, but not for SAMHD1 degradation, had a reduced binding affinity for DCAF1, but not for TASOR. In macrophages, Vpx R34A-R42A and Vpx R42A-Q47A-V48A, strongly impaired in DCAF1, but not in TASOR binding, could not degrade TASOR, while being efficient in degrading SAMHD1. Altogether, our results highlight the central role of a robust Vpx-DCAF1 association to trigger TASOR degradation. We then propose a model in which Vpx interacts with both TASOR and DCAF1 to stabilize a TASOR-DCAF1 complex. Furthermore, our work identifies Vpx mutants enabling the study of HUSH restriction independently from SAMHD1 restriction in primary myeloid cells. Human Immunodeficiency Virus (HIV) is still a major public health issue. The understanding of the molecular battle occurring during viral infection, between HIV components and cellular antiviral factors, the so-called restriction factors, is a key determinant for new treatment development. Namely, HIV auxiliary proteins are powerful to induce the downregulation of cellular restriction factors by hijacking the Ubiquitin/proteasome pathway, in order to facilitate the completion of a well-processed HIV replication cycle. For instance, HIV-2 Vpx eases reverse transcription in myeloid cells by counteracting the SAMDH1 restriction factor. More recently, we discovered the ability of Vpx to induce the degradation of the HUSH epigenetic repressor complex to favor in turn, the expression of the provirus. In this study, we uncovered the mechanisms by which Vpx antagonizes TASOR, the core subunit of the HUSH complex. We highlighted key differences between Vpx-induced TASOR and SAMHD1 degradation. These findings will help to propose strategies to study or to target either HUSH or SAMHD1, especially in myeloid cells where SAMHD1 restriction operates.
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Affiliation(s)
| | - Roy Matkovic
- Institut Cochin, Université de Paris, INSERM U1016, Paris, France
| | - Pauline Larrous
- Institut Cochin, Université de Paris, INSERM U1016, Paris, France
| | - Marina Morel
- Institut Cochin, Université de Paris, INSERM U1016, Paris, France
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13
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Denner J. Porcine Endogenous Retroviruses and Xenotransplantation, 2021. Viruses 2021; 13:v13112156. [PMID: 34834962 PMCID: PMC8625113 DOI: 10.3390/v13112156] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/06/2021] [Accepted: 10/20/2021] [Indexed: 12/25/2022] Open
Abstract
Porcine endogenous retroviruses (PERVs) are integrated in the genome of all pigs, and some of them are able to infect human cells. Therefore, PERVs pose a risk for xenotransplantation, the transplantation of pig cells, tissues, or organ to humans in order to alleviate the shortage of human donor organs. Up to 2021, a huge body of knowledge about PERVs has been accumulated regarding their biology, including replication, recombination, origin, host range, and immunosuppressive properties. Until now, no PERV transmission has been observed in clinical trials transplanting pig islet cells into diabetic humans, in preclinical trials transplanting pig cells and organs into nonhuman primates with remarkable long survival times of the transplant, and in infection experiments with several animal species. Nevertheless, in order to prevent virus transmission to the recipient, numerous strategies have been developed, including selection of PERV-C-free animals, RNA interference, antiviral drugs, vaccination, and genome editing. Furthermore, at present there are no more experimental approaches to evaluate the full risk until we move to the clinic.
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Affiliation(s)
- Joachim Denner
- Department of Veterinary Medicine, Institute of Virology, Free University Berlin, 14163 Berlin, Germany
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14
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Seal S, Dharmarajan G, Khan I. Evolution of pathogen tolerance and emerging infections: A missing experimental paradigm. eLife 2021; 10:e68874. [PMID: 34544548 PMCID: PMC8455132 DOI: 10.7554/elife.68874] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 08/23/2021] [Indexed: 12/11/2022] Open
Abstract
Researchers worldwide are repeatedly warning us against future zoonotic diseases resulting from humankind's insurgence into natural ecosystems. The same zoonotic pathogens that cause severe infections in a human host frequently fail to produce any disease outcome in their natural hosts. What precise features of the immune system enable natural reservoirs to carry these pathogens so efficiently? To understand these effects, we highlight the importance of tracing the evolutionary basis of pathogen tolerance in reservoir hosts, while drawing implications from their diverse physiological and life-history traits, and ecological contexts of host-pathogen interactions. Long-term co-evolution might allow reservoir hosts to modulate immunity and evolve tolerance to zoonotic pathogens, increasing their circulation and infectious period. Such processes can also create a genetically diverse pathogen pool by allowing more mutations and genetic exchanges between circulating strains, thereby harboring rare alive-on-arrival variants with extended infectivity to new hosts (i.e., spillover). Finally, we end by underscoring the indispensability of a large multidisciplinary empirical framework to explore the proposed link between evolved tolerance, pathogen prevalence, and spillover in the wild.
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Affiliation(s)
| | - Guha Dharmarajan
- Savannah River Ecology Laboratory, University of GeorgiaAikenUnited States
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15
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APOBEC3F Constitutes a Barrier to Successful Cross-Species Transmission of Simian Immunodeficiency Virus SIVsmm to Humans. J Virol 2021; 95:e0080821. [PMID: 34132575 DOI: 10.1128/jvi.00808-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Simian immunodeficiency virus infecting sooty mangabeys (SIVsmm) has been transmitted to humans on at least nine occasions, giving rise to human immunodeficiency virus type 2 (HIV-2) groups A to I. SIVsmm isolates replicate in human T cells and seem capable of overcoming major human restriction factors without adaptation. However, only groups A and B are responsible for the HIV-2 epidemic in sub-Saharan Africa, and it is largely unclear whether adaptive changes were associated with spread in humans. To address this, we examined the sensitivity of infectious molecular clones (IMCs) of five HIV-2 strains and representatives of five different SIVsmm lineages to various APOBEC3 proteins. We confirmed that SIVsmm strains replicate in human T cells, albeit with more variable replication fitness and frequently lower efficiency than HIV-2 IMCs. Efficient viral propagation was generally dependent on intact vif genes, highlighting the need for counteraction of APOBEC3 proteins. On average, SIVsmm was more susceptible to inhibition by human APOBEC3D, -F, -G, and -H than HIV-2. For example, human APOBEC3F reduced infectious virus yield of SIVsmm by ∼80% but achieved only ∼40% reduction in the case of HIV-2. Functional and mutational analyses of human- and monkey-derived alleles revealed that an R128T polymorphism in APOBEC3F contributes to species-specific counteraction by HIV-2 and SIVsmm Vifs. In addition, a T84S substitution in SIVsmm Vif increased its ability to counteract human APOBEC3F. Altogether, our results confirm that SIVsmm Vif proteins show intrinsic activity against human APOBEC3 proteins but also demonstrate that epidemic HIV-2 strains evolved an increased ability to counteract this class of restriction factors during human adaptation. IMPORTANCE Viral zoonoses pose a significant threat to human health, and it is important to understand determining factors. SIVs infecting great apes gave rise to HIV-1. In contrast, SIVs infecting African monkey species have not been detected in humans, with one notable exception. SIVsmm from sooty mangabeys has crossed the species barrier to humans on at least nine independent occasions and seems capable of overcoming many innate defense mechanisms without adaptation. Here, we confirmed that SIVsmm Vif proteins show significant activity against human APOBEC3 proteins. Our analyses also revealed, however, that different lineages of SIVsmm are significantly more susceptible to inhibition by various human APOBEC3 proteins than HIV-2 strains. Mutational analyses suggest that an R128T substitution in APOBEC3F and a T84S change in Vif contribute to species-specific counteraction by HIV-2 and SIVsmm. Altogether, our results support that epidemic HIV-2 strains acquired increased activity against human APOBEC3 proteins to clear this restrictive barrier.
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16
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Modular Lentiviral Vectors for Highly Efficient Transgene Expression in Resting Immune Cells. Viruses 2021; 13:v13061170. [PMID: 34207354 PMCID: PMC8235771 DOI: 10.3390/v13061170] [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: 04/29/2021] [Revised: 06/08/2021] [Accepted: 06/16/2021] [Indexed: 11/17/2022] Open
Abstract
Gene/cell therapies are promising strategies for the many presently incurable diseases. A key step in this process is the efficient delivery of genes and gene-editing enzymes to many cell types that may be resistant to lentiviral vector transduction. Herein we describe tuning of a lentiviral gene therapy platform to focus on genetic modifications of resting CD4+ T cells. The motivation for this was to find solutions for HIV gene therapy efforts. Through selection of the optimal viral envelope and further modification to its expression, lentiviral fusogenic delivery into resting CD4+ T cells exceeded 80%, yet Sterile Alpha Motif and HD domain 1 (SAMHD1) dependent and independent intracellular restriction factors within resting T cells then dominate delivery and integration of lentiviral cargo. Overcoming SAMHD1-imposed restrictions, only observed up to 6-fold increase in transduction, with maximal gene delivery and expression of 35%. To test if the biologically limiting steps of lentiviral delivery are reverse transcription and integration, we re-engineered lentiviral vectors to simply express biologically active mRNA to direct transgene expression in the cytoplasm. In this setting, we observed gene expression in up to 65% of resting CD4+ T cells using unconcentrated MS2 lentivirus-like particles (MS2-LVLPs). Taken together, our findings support a gene therapy platform that could be readily used in resting T cell gene editing.
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17
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Gaba A, Flath B, Chelico L. Examination of the APOBEC3 Barrier to Cross Species Transmission of Primate Lentiviruses. Viruses 2021; 13:1084. [PMID: 34200141 PMCID: PMC8228377 DOI: 10.3390/v13061084] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/12/2022] Open
Abstract
The transmission of viruses from animal hosts into humans have led to the emergence of several diseases. Usually these cross-species transmissions are blocked by host restriction factors, which are proteins that can block virus replication at a specific step. In the natural virus host, the restriction factor activity is usually suppressed by a viral antagonist protein, but this is not the case for restriction factors from an unnatural host. However, due to ongoing viral evolution, sometimes the viral antagonist can evolve to suppress restriction factors in a new host, enabling cross-species transmission. Here we examine the classical case of this paradigm by reviewing research on APOBEC3 restriction factors and how they can suppress human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV). APOBEC3 enzymes are single-stranded DNA cytidine deaminases that can induce mutagenesis of proviral DNA by catalyzing the conversion of cytidine to promutagenic uridine on single-stranded viral (-)DNA if they escape the HIV/SIV antagonist protein, Vif. APOBEC3 degradation is induced by Vif through the proteasome pathway. SIV has been transmitted between Old World Monkeys and to hominids. Here we examine the adaptations that enabled such events and the ongoing impact of the APOBEC3-Vif interface on HIV in humans.
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Affiliation(s)
- Amit Gaba
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SA S7H 0E5, Canada
| | - Ben Flath
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SA S7H 0E5, Canada
| | - Linda Chelico
- Department of Biochemistry, Microbiology, and Immunology, University of Saskatchewan, Saskatoon, SA S7H 0E5, Canada
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18
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Coggins SA, Kim DH, Schinazi RF, Desrosier RC, Kim B. Enhanced enzyme kinetics of reverse transcriptase variants cloned from animals infected with SIVmac239 lacking viral protein X. J Biol Chem 2020; 295:16975-16986. [PMID: 33008888 PMCID: PMC7863885 DOI: 10.1074/jbc.ra120.015273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/01/2020] [Indexed: 12/14/2022] Open
Abstract
HIV Type 1 (HIV-1) and simian immunodeficiency virus (SIV) display differential replication kinetics in macrophages. This is because high expression levels of the active host deoxynucleotide triphosphohydrolase sterile α motif domain and histidine-aspartate domain-containing protein 1 (SAMHD1) deplete intracellular dNTPs, which restrict HIV-1 reverse transcription, and result in a restrictive infection in this myeloid cell type. Some SIVs overcome SAMHD1 restriction using viral protein X (Vpx), a viral accessory protein that induces proteasomal degradation of SAMHD1, increasing cellular dNTP concentrations and enabling efficient proviral DNA synthesis. We previously reported that SAMHD1-noncounteracting lentiviruses may have evolved to harbor RT proteins that efficiently polymerize DNA, even at low dNTP concentrations, to circumvent SAMHD1 restriction. Here we investigated whether RTs from SIVmac239 virus lacking a Vpx protein evolve during in vivo infection to more efficiently synthesize DNA at the low dNTP concentrations found in macrophages. Sequence analysis of RTs cloned from Vpx (+) and Vpx (-) SIVmac239-infected animals revealed that Vpx (-) RTs contained more extensive mutations than Vpx (+) RTs. Although the amino acid substitutions were dispersed indiscriminately across the protein, steady-state and pre-steady-state analysis demonstrated that selected SIVmac239 Vpx (-) RTs are characterized by higher catalytic efficiency and incorporation efficiency values than RTs cloned from SIVmac239 Vpx (+) infections. Overall, this study supports the possibility that the loss of Vpx may generate in vivo SIVmac239 RT variants that can counteract the limited availability of dNTP substrate in macrophages.
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Affiliation(s)
- Si'Ana A Coggins
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Dong-Hyun Kim
- Department of Pharmacy, Kyung-Hee University, Seoul, South Korea
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Ronald C Desrosier
- Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA; Children's Healthcare of Atlanta, Atlanta, Georgia, USA.
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19
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Zhang Z, Perković M, Gu Q, Balakrishnan K, Sangwiman A, Häussinger D, Lindemann D, Münk C. HIV-2 Vif and foamy virus Bet antagonize APOBEC3B by different mechanisms. Virology 2020; 554:17-27. [PMID: 33333348 DOI: 10.1016/j.virol.2020.11.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/13/2020] [Accepted: 11/17/2020] [Indexed: 11/17/2022]
Abstract
The family of human APOBEC3 (A3) restriction factors is formed by seven different proteins, A3A-D and A3F-H. Among these A3s, A3B harbors strong restriction activity against several retroviruses, such as SIV, and MLV. How lentiviruses and other retroviruses, prevalent in many primate species, counteract A3B is poorly understood. In this study, we found that A3B strongly inhibited SIVmac and HIV-2 infectivity, which was antagonized by their Vif proteins. Both SIVmac and HIV-2 Vifs diminished the protein level of A3B in viral producer cells, and hindered A3B incorporation into viral particles. We observed that HIV-2 Vif binds A3B and induces its degradation by assembly of an A3-Vif-CUL5-ElonginB/C E3-ligase complex. A3B and HIV-2 Vif localize and interact in the nucleus. In addition, we also found that the accessory protein Bet of prototype foamy virus (PFV) significantly antagonized the anti-SIVmac activity of A3B. Like Vif, Bet prevented the incorporation of A3B into viral particles. However, in contrast to Vif Bet did not induce the degradation of A3B. Rather, Bet binds A3B to block formation of high molecular weight A3B complexes and induces A3B cytoplasmic trapping. In summary, these findings indicate that A3B is recognized by diverse retroviruses and counteracted by virus-specific pathways that could be targeted to inhibit A3B mutating activity in cancers.
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Affiliation(s)
- Zeli Zhang
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Mario Perković
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Qinyong Gu
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Kannan Balakrishnan
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Anucha Sangwiman
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Dirk Lindemann
- Institute of Virology, Medical Faculty "Carl Gustav Carus", Technische Universität Dresden, 01307, Dresden, Germany; CRTD/DFG-Center for Regenerative Therapies, Technische Universität Dresden, 01307, Dresden, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.
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20
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Site-Specific Evolutionary Rate Shifts in HIV-1 and SIV. Viruses 2020; 12:v12111312. [PMID: 33207801 PMCID: PMC7696578 DOI: 10.3390/v12111312] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 12/28/2022] Open
Abstract
Site-specific evolutionary rate shifts are defined as protein sites, where the rate of substitution has changed dramatically across the phylogeny. With respect to a given clade, sites may either undergo a rate acceleration or a rate deceleration, reflecting a site that was conserved and became variable, or vice-versa, respectively. Sites displaying such a dramatic evolutionary change may point to a loss or gain of function at the protein site, reflecting adaptation, or they may indicate epistatic interactions among sites. Here, we analyzed full genomes of HIV and SIV-1 and identified 271 rate-shifting sites along the HIV-1/SIV phylogeny. The majority of rate shifts occurred at long branches, often corresponding to cross-species transmission branches. We noted that in most proteins, the number of rate accelerations and decelerations was equal, and we suggest that this reflects epistatic interactions among sites. However, several accessory proteins were enriched for either accelerations or decelerations, and we suggest that this may be a signature of adaptation to new hosts. Interestingly, the non-pandemic HIV-1 group O clade exhibited a substantially higher number of rate-shift events than the pandemic group M clade. We propose that this may be a reflection of the height of the species barrier between gorillas and humans versus chimpanzees and humans. Our results provide a genome-wide view of the constraints operating on proteins of HIV-1 and SIV.
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21
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Thippeshappa R, Kimata JT, Kaushal D. Toward a Macaque Model of HIV-1 Infection: Roadblocks, Progress, and Future Strategies. Front Microbiol 2020; 11:882. [PMID: 32477302 PMCID: PMC7237640 DOI: 10.3389/fmicb.2020.00882] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/16/2020] [Indexed: 12/15/2022] Open
Abstract
The human-specific tropism of Human Immunodeficiency Virus Type 1 (HIV-1) has complicated the development of a macaque model of HIV-1 infection/AIDS that is suitable for preclinical evaluation of vaccines and novel treatment strategies. Several innate retroviral restriction factors, such as APOBEC3 family of proteins, TRIM5α, BST2, and SAMHD1, that prevent HIV-1 replication have been identified in macaque cells. Accessory proteins expressed by Simian Immunodeficiency virus (SIV) such as viral infectivity factor (Vif), viral protein X (Vpx), viral protein R (Vpr), and negative factor (Nef) have been shown to play key roles in overcoming these restriction factors in macaque cells. Thus, substituting HIV-1 accessory genes with those from SIV may enable HIV-1 replication in macaques. We and others have constructed macaque-tropic HIV-1 derivatives [also called simian-tropic HIV-1 (stHIV-1) or Human-Simian Immunodeficiency Virus (HSIV)] carrying SIV vif to overcome APOBEC3 family proteins. Additional modifications to HIV-1 gag in some of the macaque-tropic HIV-1 have also been done to overcome TRIM5α restriction in rhesus and cynomolgus macaques. Although these viruses replicate persistently in macaque species, they do not result in CD4 depletion. Thus, these studies suggest that additional blocks to HIV-1 replication exist in macaques that prevent high-level viral replication. Furthermore, serial animal-to-animal passaging of macaque-tropic HIV-1 in vivo has not resulted in pathogenic variants that cause AIDS in immunocompetent macaques. In this review, we discuss recent developments made toward developing macaque model of HIV-1 infection.
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Affiliation(s)
- Rajesh Thippeshappa
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States
| | - Jason T Kimata
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States
| | - Deepak Kaushal
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, United States
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22
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Binning JM, Chesarino NM, Emerman M, Gross JD. Structural Basis for a Species-Specific Determinant of an SIV Vif Protein toward Hominid APOBEC3G Antagonism. Cell Host Microbe 2020; 26:739-747.e4. [PMID: 31830442 DOI: 10.1016/j.chom.2019.10.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/05/2019] [Accepted: 10/22/2019] [Indexed: 12/31/2022]
Abstract
Primate lentiviruses encode a Vif protein that counteracts the host antiviral APOBEC3 (A3) family members. The adaptation of Vif to species-specific A3 determinants is a critical event that allowed the spillover of a lentivirus from monkey reservoirs to chimpanzees and subsequently to humans, which gave rise to HIV-1 and the acquired immune deficiency syndrome (AIDS) pandemic. How Vif-A3 protein interactions are remodeled during evolution is unclear. Here, we report a 2.94 Å crystal structure of the Vif substrate receptor complex from simian immunodeficiency virus isolated from red-capped mangabey (SIVrcm). The structure of the SIVrcm Vif complex illuminates the stage of lentiviral Vif evolution that is immediately prior to entering hominid primates. Structure-function studies reveal the adaptations that allowed SIVrcm Vif to antagonize hominid A3G. These studies show a partitioning between an evolutionarily dynamic specificity determinant and a conserved protein interacting surface on Vif that enables adaptation while maintaining protein interactions required for potent A3 antagonism.
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Affiliation(s)
- Jennifer M Binning
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Nicholas M Chesarino
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Michael Emerman
- Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
| | - John D Gross
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158, USA.
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23
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SAMHD1 Functions and Human Diseases. Viruses 2020; 12:v12040382. [PMID: 32244340 PMCID: PMC7232136 DOI: 10.3390/v12040382] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 12/12/2022] Open
Abstract
Deoxynucleoside triphosphate (dNTP) molecules are essential for the replication and maintenance of genomic information in both cells and a variety of viral pathogens. While the process of dNTP biosynthesis by cellular enzymes, such as ribonucleotide reductase (RNR) and thymidine kinase (TK), has been extensively investigated, a negative regulatory mechanism of dNTP pools was recently found to involve sterile alpha motif (SAM) domain and histidine-aspartate (HD) domain-containing protein 1, SAMHD1. When active, dNTP triphosphohydrolase activity of SAMHD1 degrades dNTPs into their 2'-deoxynucleoside (dN) and triphosphate subparts, steadily depleting intercellular dNTP pools. The differential expression levels and activation states of SAMHD1 in various cell types contributes to unique dNTP pools that either aid (i.e., dividing T cells) or restrict (i.e., nondividing macrophages) viral replication that consumes cellular dNTPs. Genetic mutations in SAMHD1 induce a rare inflammatory encephalopathy called Aicardi-Goutières syndrome (AGS), which phenotypically resembles viral infection. Recent publications have identified diverse roles for SAMHD1 in double-stranded break repair, genome stability, and the replication stress response through interferon signaling. Finally, a series of SAMHD1 mutations were also reported in various cancer cell types while why SAMHD1 is mutated in these cancer cells remains to investigated. Here, we reviewed a series of studies that have begun illuminating the highly diverse roles of SAMHD1 in virology, immunology, and cancer biology.
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Douglas GM, Langille MGI. Current and Promising Approaches to Identify Horizontal Gene Transfer Events in Metagenomes. Genome Biol Evol 2019; 11:2750-2766. [PMID: 31504488 PMCID: PMC6777429 DOI: 10.1093/gbe/evz184] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/19/2019] [Indexed: 12/16/2022] Open
Abstract
High-throughput shotgun metagenomics sequencing has enabled the profiling of myriad natural communities. These data are commonly used to identify gene families and pathways that were potentially gained or lost in an environment and which may be involved in microbial adaptation. Despite the widespread interest in these events, there are no established best practices for identifying gene gain and loss in metagenomics data. Horizontal gene transfer (HGT) represents several mechanisms of gene gain that are especially of interest in clinical microbiology due to the rapid spread of antibiotic resistance genes in natural communities. Several additional mechanisms of gene gain and loss, including gene duplication, gene loss-of-function events, and de novo gene birth are also important to consider in the context of metagenomes but have been less studied. This review is largely focused on detecting HGT in prokaryotic metagenomes, but methods for detecting these other mechanisms are first discussed. For this article to be self-contained, we provide a general background on HGT and the different possible signatures of this process. Lastly, we discuss how improved assembly of genomes from metagenomes would be the most straight-forward approach for improving the inference of gene gain and loss events. Several recent technological advances could help improve metagenome assemblies: long-read sequencing, determining the physical proximity of contigs, optical mapping of short sequences along chromosomes, and single-cell metagenomics. The benefits and limitations of these advances are discussed and open questions in this area are highlighted.
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Affiliation(s)
- Gavin M Douglas
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Morgan G I Langille
- Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
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25
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Muslin C, Mac Kain A, Bessaud M, Blondel B, Delpeyroux F. Recombination in Enteroviruses, a Multi-Step Modular Evolutionary Process. Viruses 2019; 11:E859. [PMID: 31540135 PMCID: PMC6784155 DOI: 10.3390/v11090859] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 01/15/2023] Open
Abstract
RNA recombination is a major driving force in the evolution and genetic architecture shaping of enteroviruses. In particular, intertypic recombination is implicated in the emergence of most pathogenic circulating vaccine-derived polioviruses, which have caused numerous outbreaks of paralytic poliomyelitis worldwide. Recent experimental studies that relied on recombination cellular systems mimicking natural genetic exchanges between enteroviruses provided new insights into the molecular mechanisms of enterovirus recombination and enabled to define a new model of genetic plasticity for enteroviruses. Homologous intertypic recombinant enteroviruses that were observed in nature would be the final products of a multi-step process, during which precursor nonhomologous recombinant genomes are generated through an initial inter-genomic RNA recombination event and can then evolve into a diversity of fitter homologous recombinant genomes over subsequent intra-genomic rearrangements. Moreover, these experimental studies demonstrated that the enterovirus genome could be defined as a combination of genomic modules that can be preferentially exchanged through recombination, and enabled defining the boundaries of these recombination modules. These results provided the first experimental evidence supporting the theoretical model of enterovirus modular evolution previously elaborated from phylogenetic studies of circulating enterovirus strains. This review summarizes our current knowledge regarding the mechanisms of recombination in enteroviruses and presents a new evolutionary process that may apply to other RNA viruses.
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Affiliation(s)
- Claire Muslin
- One Health Research Group, Faculty of Health Sciences, Universidad de las Américas, Quito EC170125, Pichincha, Ecuador.
| | - Alice Mac Kain
- Institut Pasteur, Viral Populations and Pathogenesis Unit, CNRS UMR 3569, 75015 Paris, France.
| | - Maël Bessaud
- Institut Pasteur, Viral Populations and Pathogenesis Unit, CNRS UMR 3569, 75015 Paris, France.
| | - Bruno Blondel
- Institut Pasteur, Biology of Enteric Viruses Unit, 75015 Paris, France.
- INSERM U994, Institut National de la Santé et de la Recherche Médicale, 75015 Paris, France.
| | - Francis Delpeyroux
- Institut Pasteur, Biology of Enteric Viruses Unit, 75015 Paris, France.
- INSERM U994, Institut National de la Santé et de la Recherche Médicale, 75015 Paris, France.
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26
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Coggins SA, Holler JM, Kimata JT, Kim DH, Schinazi RF, Kim B. Efficient pre-catalytic conformational change of reverse transcriptases from SAMHD1 non-counteracting primate lentiviruses during dNTP incorporation. Virology 2019; 537:36-44. [PMID: 31442614 DOI: 10.1016/j.virol.2019.08.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/10/2019] [Accepted: 08/12/2019] [Indexed: 10/26/2022]
Abstract
Unlike HIV-1, HIV-2 and some SIV strains replicate at high dNTP concentrations even in macrophages due to their accessory proteins, Vpx or Vpr, that target SAMHD1 dNTPase for proteasomal degradation. We previously reported that HIV-1 reverse transcriptase (RT) efficiently synthesizes DNA even at low dNTP concentrations because HIV-1 RT displays faster pre-steady state kpol values than SAMHD1 counteracting lentiviral RTs. Here, since the kpol step consists of two sequential sub-steps post dNTP binding, conformational change and chemistry, we investigated which of the two sub-steps RTs from SAMHD1 non-counteracting viruses accelerate in order to complete reverse transcription in the limited dNTP pools found in macrophages. Our study demonstrates that RTs of SAMHD1 non-counteracting lentiviruses have a faster conformational change rate during dNTP incorporation, supporting that these lentiviruses may have evolved to harbor RTs that can efficiently execute the conformational change step in order to circumvent SAMHD1 restriction and dNTP depletion in macrophages.
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Affiliation(s)
- Si'Ana A Coggins
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Jessica M Holler
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Jason T Kimata
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, 77030, Texas, USA
| | - Dong-Hyun Kim
- College of Pharmacy, Kyung Hee University, Seoul, 04427, South Korea
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, 30322, USA; College of Pharmacy, Kyung Hee University, Seoul, 04427, South Korea; Children's Healthcare of Atlanta, Atlanta, 30322, USA.
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Role of co-expressed APOBEC3F and APOBEC3G in inducing HIV-1 drug resistance. Heliyon 2019; 5:e01498. [PMID: 31025011 PMCID: PMC6475876 DOI: 10.1016/j.heliyon.2019.e01498] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/24/2019] [Accepted: 04/05/2019] [Indexed: 01/04/2023] Open
Abstract
The APOBEC3 enzymes can induce mutagenesis of HIV-1 proviral DNA through the deamination of cytosine. HIV-1 overcomes this restriction through the viral protein Vif that induces APOBEC3 proteasomal degradation. Within this dynamic host-pathogen relationship, the APOBEC3 enzymes have been found to be beneficial, neutral, or detrimental to HIV-1 biology. Here, we assessed the ability of co-expressed APOBEC3F and APOBEC3G to induce HIV-1 resistance to antiviral drugs. We found that co-expression of APOBEC3F and APOBEC3G enabled partial resistance of APOBEC3F to Vif-mediated degradation with a corresponding increase in APOBEC3F-induced deaminations in the presence of Vif, in addition to APOBEC3G-induced deaminations. We recovered HIV-1 drug resistant variants resulting from APOBEC3-induced mutagenesis, but these variants were less able to replicate than drug resistant viruses derived from RT-induced mutations alone. The data support a model in which APOBEC3 enzymes cooperate to restrict HIV-1, promoting viral inactivation over evolution to drug resistance.
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28
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Majer C, Schüssler JM, König R. Intertwined: SAMHD1 cellular functions, restriction, and viral evasion strategies. Med Microbiol Immunol 2019; 208:513-529. [PMID: 30879196 DOI: 10.1007/s00430-019-00593-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 03/08/2019] [Indexed: 01/01/2023]
Abstract
SAMHD1 was initially described for its ability to efficiently restrict HIV-1 replication in myeloid cells and resting CD4+ T cells. However, a growing body of evidence suggests that SAMHD1-mediated restriction is by far not limited to lentiviruses, but seems to be a general concept that applies to most retroviruses and at least a number of DNA viruses. SAMHD1 anti-viral activity was long believed to be solely due to its ability to deplete cellular dNTPs by enzymatic degradation. However, since its discovery, several new functions have been attributed to SAMHD1. It has been demonstrated to bind nucleic acids, to modulate innate immunity, as well as to participate in the DNA damage response and resolution of stalled replication forks. Consequently, it is likely that SAMHD1-mediated anti-viral activity is not or not exclusively mediated through its dNTPase activity. Therefore, in this review, we summarize current knowledge on SAMHD1 cellular functions and systematically discuss how these functions could contribute to the restriction of a broad range of viruses besides retroviruses: herpesviruses, poxviruses and hepatitis B virus. Furthermore, we aim to highlight different ways how viruses counteract SAMHD1-mediated restriction to bypass the SAMHD1-mediated block to viral infection.
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Affiliation(s)
- Catharina Majer
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany
| | | | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany. .,Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA. .,German Center for Infection Research (DZIF), 63225, Langen, Germany. .,Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany.
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Abstract
HIV, the causative agent of AIDS, has a complex evolutionary history involving several cross-species transmissions and recombination events as well as changes in the repertoire and function of its accessory genes. Understanding these events and the adaptations to new host species provides key insights into innate defense mechanisms, viral dependencies on cellular factors, and prerequisites for the emergence of the AIDS pandemic. In addition, understanding the factors and adaptations required for the spread of HIV in the human population helps to better assess the risk of future lentiviral zoonoses and provides clues to how improved control of viral replication can be achieved. Here, we summarize our current knowledge on viral features and adaptations preceding the AIDS pandemic. We aim at providing a viral point of view, focusing on known key hurdles of each cross-species transmission and the mechanisms that HIV and its simian precursors evolved to overcome them.
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Affiliation(s)
- Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Centre, Ulm 89081, Germany
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Centre, Ulm 89081, Germany.
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30
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Chougui G, Martin M, Matkovic R, Etienne L, Margottin-Goguet F. [Noise from Vpx: "HUSH"!]. Med Sci (Paris) 2019; 35:9-12. [PMID: 30672455 DOI: 10.1051/medsci/2018312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Ghina Chougui
- Inserm, U1016, Institut Cochin, 22, rue Méchain, 75014 Paris, France - CNRS, UMR8104, Paris, France - Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Michael Martin
- Inserm, U1016, Institut Cochin, 22, rue Méchain, 75014 Paris, France - CNRS, UMR8104, Paris, France - Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Roy Matkovic
- Inserm, U1016, Institut Cochin, 22, rue Méchain, 75014 Paris, France - CNRS, UMR8104, Paris, France - Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Lucie Etienne
- CIRI - International center for infectiology research, Inserm U1111, Université Claude Bernard Lyon 1, CNRS UMR5308, École normale supérieure de Lyon, Université Lyon, F-69007, Lyon, France
| | - Florence Margottin-Goguet
- Inserm, U1016, Institut Cochin, 22, rue Méchain, 75014 Paris, France - CNRS, UMR8104, Paris, France - Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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31
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OhAinle M, Helms L, Vermeire J, Roesch F, Humes D, Basom R, Delrow JJ, Overbaugh J, Emerman M. A virus-packageable CRISPR screen identifies host factors mediating interferon inhibition of HIV. eLife 2018; 7:e39823. [PMID: 30520725 PMCID: PMC6286125 DOI: 10.7554/elife.39823] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 11/13/2018] [Indexed: 12/14/2022] Open
Abstract
Interferon (IFN) inhibits HIV replication by inducing antiviral effectors. To comprehensively identify IFN-induced HIV restriction factors, we assembled a CRISPR sgRNA library of Interferon Stimulated Genes (ISGs) into a modified lentiviral vector that allows for packaging of sgRNA-encoding genomes in trans into budding HIV-1 particles. We observed that knockout of Zinc Antiviral Protein (ZAP) improved the performance of the screen due to ZAP-mediated inhibition of the vector. A small panel of IFN-induced HIV restriction factors, including MxB, IFITM1, Tetherin/BST2 and TRIM5alpha together explain the inhibitory effects of IFN on the CXCR4-tropic HIV-1 strain, HIV-1LAI, in THP-1 cells. A second screen with a CCR5-tropic primary strain, HIV-1Q23.BG505, described an overlapping, but non-identical, panel of restriction factors. Further, this screen also identifies HIV dependency factors. The ability of IFN-induced restriction factors to inhibit HIV strains to replicate in human cells suggests that these human restriction factors are incompletely antagonized. Editorial note This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
- Molly OhAinle
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Louisa Helms
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Jolien Vermeire
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Ferdinand Roesch
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Daryl Humes
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Ryan Basom
- Genomics and Bioinformatics Shared ResourceFred Hutchinson Cancer Research CenterSeattleUnited States
| | - Jeffrey J Delrow
- Genomics and Bioinformatics Shared ResourceFred Hutchinson Cancer Research CenterSeattleUnited States
| | - Julie Overbaugh
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
| | - Michael Emerman
- Divisions of Human Biology and Basic SciencesFred Hutchinson Cancer Research CenterWashingtonUnited States
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32
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Abstract
Pandemic HIV-1, a human lentivirus, is the result of zoonotic transmission of SIV from chimpanzees (SIVcpz). How SIVcpz established spread in humans after spillover is an outstanding question. Lentiviral cross-species transmissions are exceptionally rare events. Nevertheless, the chimpanzee and the gorilla were part of the transmission chains that resulted in sustained infections that evolved into HIV-1. Although many restriction factors can repress the early stages of lentiviral replication, others target replication during the late phases. In some cases, viruses incorporate host proteins that interfere with subsequent rounds of replication. Though limited and small, HIVs and SIVs, including SIVcpz can use their genome products to modulate and escape some of these barriers and thus establish a chronic infection.
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Affiliation(s)
- Augustin Penda Twizerimana
- Clinic for Gastroenterology, Hepatology & Infectiology, Medical Faculty, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Rachel Scheck
- Clinic for Gastroenterology, Hepatology & Infectiology, Medical Faculty, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology & Infectiology, Medical Faculty, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology & Infectiology, Medical Faculty, Heinrich-Heine-University, Moorenstr. 5, 40225 Düsseldorf, Germany
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33
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Meyerson NR, Warren CJ, Vieira DASA, Diaz-Griferro F, Sawyer SL. Species-specific vulnerability of RanBP2 shaped the evolution of SIV as it transmitted in African apes. PLoS Pathog 2018. [PMID: 29518153 PMCID: PMC5843284 DOI: 10.1371/journal.ppat.1006906] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
HIV-1 arose as the result of spillover of simian immunodeficiency viruses (SIVs) from great apes in Africa, namely from chimpanzees and gorillas. Chimpanzees and gorillas were, themselves, infected with SIV after virus spillover from African monkeys. During spillover events, SIV is thought to require adaptation to the new host species. The host barriers that drive viral adaptation have predominantly been attributed to restriction factors, rather than cofactors (host proteins exploited to promote viral replication). Here, we consider the role of one cofactor, RanBP2, in providing a barrier that drove viral genome evolution during SIV spillover events. RanBP2 (also known as Nup358) is a component of the nuclear pore complex known to facilitate nuclear entry of HIV-1. Our data suggest that transmission of SIV from monkeys to chimpanzees, and then from chimpanzees to gorillas, both coincided with changes in the viral capsid that allowed interaction with RanBP2 of the new host species. However, human RanBP2 subsequently provided no barrier to the zoonotic transmission of SIV from chimpanzees or gorillas, indicating that chimpanzee- and gorilla-adapted SIVs are pre-adapted to humans in this regard. Our observations are in agreement with RanBP2 driving virus evolution during cross-species transmissions of SIV, particularly in the transmissions to and between great ape species. Multiple times, HIV-1 has entered the human population after emerging from a viral reservoir that exists in African primates. First, simian immunodeficiency virus (SIV) made the jump from monkeys into African great apes, and then from apes (namely, chimpanzees and gorillas) into humans. It is well appreciated that restriction factors, which are specialized proteins of the innate immune system, acted as host-specific barriers that drove virus adaptation during these spillover events. Here, we present data showing that a major constituent of the nuclear pore complex, RanBP2, was also a barrier to the spillover of SIVs, particularly in great ape species. Spillover of SIV into chimpanzee and gorilla populations required that the SIV capsid mutate to establish interaction with RanBP2 in the new host species. Our study highlights how essential housekeeping proteins, despite being generally more evolutionarily conserved than restriction factors, can also drive virus evolution during spillover events.
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Affiliation(s)
- Nicholas R. Meyerson
- BioFrontiers Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, United States of America
| | - Cody J. Warren
- BioFrontiers Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, United States of America
| | - Daniel A. S. A. Vieira
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States of America
| | - Felipe Diaz-Griferro
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States of America
| | - Sara L. Sawyer
- BioFrontiers Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, United States of America
- * E-mail:
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Experimental Adaptive Evolution of Simian Immunodeficiency Virus SIVcpz to Pandemic Human Immunodeficiency Virus Type 1 by Using a Humanized Mouse Model. J Virol 2018; 92:JVI.01905-17. [PMID: 29212937 DOI: 10.1128/jvi.01905-17] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 11/28/2017] [Indexed: 12/31/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1), the causative agent of AIDS, originated from simian immunodeficiency virus from chimpanzees (SIVcpz), the precursor of the human virus, approximately 100 years ago. This indicates that HIV-1 has emerged through the cross-species transmission of SIVcpz from chimpanzees to humans. However, it remains unclear how SIVcpz has evolved into pandemic HIV-1 in humans. To address this question, we inoculated three SIVcpz strains (MB897, EK505, and MT145), four pandemic HIV-1 strains (NL4-3, NLCSFV3, JRCSF, and AD8), and two nonpandemic HIV-1 strains (YBF30 and DJO0131). Humanized mice infected with SIVcpz strain MB897, a virus phylogenetically similar to pandemic HIV-1, exhibited a peak viral load comparable to that of mice infected with pandemic HIV-1, while peak viral loads of mice infected with SIVcpz strain EK505 or MT145 as well as nonpandemic HIV-1 strains were significantly lower. These results suggest that SIVcpz strain MB897 is preadapted to humans, unlike the other SIVcpz strains. Moreover, viral RNA sequencing of MB897-infected humanized mice identified a nonsynonymous mutation in env, a G413R substitution in gp120. The infectivity of the gp120 G413R mutant of MB897 was significantly higher than that of parental MB897. Furthermore, we demonstrated that the gp120 G413R mutant of MB897 augments the capacity for viral replication in both in vitro cell cultures and humanized mice. Taken together, this is the first experimental investigation to use an animal model to demonstrate a gain-of-function evolution of SIVcpz into pandemic HIV-1.IMPORTANCE From the mid-20th century, humans have been exposed to the menace of infectious viral diseases, such as severe acute respiratory syndrome coronavirus, Ebola virus, and Zika virus. These outbreaks of emerging/reemerging viruses can be triggered by cross-species viral transmission from wild animals to humans, or zoonoses. HIV-1, the causative agent of AIDS, emerged by the cross-species transmission of SIVcpz, the HIV-1 precursor in chimpanzees, around 100 years ago. However, the process by which SIVcpz evolved to become HIV-1 in humans remains unclear. Here, by using a hematopoietic stem cell-transplanted humanized-mouse model, we experimentally recapitulate the evolutionary process of SIVcpz to become HIV-1. We provide evidence suggesting that a strain of SIVcpz, MB897, preadapted to infect humans over other SIVcpz strains. We further demonstrate a gain-of-function evolution of SIVcpz in infected humanized mice. Our study reveals that pandemic HIV-1 has emerged through at least two steps: preadaptation and subsequent gain-of-function mutations.
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Soper A, Kimura I, Nagaoka S, Konno Y, Yamamoto K, Koyanagi Y, Sato K. Type I Interferon Responses by HIV-1 Infection: Association with Disease Progression and Control. Front Immunol 2018; 8:1823. [PMID: 29379496 PMCID: PMC5775519 DOI: 10.3389/fimmu.2017.01823] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 12/04/2017] [Indexed: 01/08/2023] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) is the causative agent of acquired immunodeficiency syndrome and its infection leads to the onset of several disorders such as the depletion of peripheral CD4+ T cells and immune activation. HIV-1 is recognized by innate immune sensors that then trigger the production of type I interferons (IFN-Is). IFN-Is are well-known cytokines eliciting broad anti-viral effects by inducing the expression of anti-viral genes called interferon-stimulated genes (ISGs). Extensive in vitro studies using cell culture systems have elucidated that certain ISGs such as APOBEC3G, tetherin, SAM domain and HD domain-containing protein 1, MX dynamin-like GTPase 2, guanylate-binding protein 5, and schlafen 11 exert robust anti-HIV-1 activity, suggesting that IFN-I responses triggered by HIV-1 infection are detrimental for viral replication and spread. However, recent studies using animal models have demonstrated that at both the acute and chronic phase of infection, the role of IFN-Is produced by HIV or SIV infection in viral replication, spread, and pathogenesis, may not be that straightforward. In this review, we describe the pluses and minuses of HIV-1 infection stimulated IFN-I responses on viral replication and pathogenesis, and further discuss the possibility for therapeutic approaches.
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Affiliation(s)
- Andrew Soper
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Izumi Kimura
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan
| | - Shumpei Nagaoka
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Yoriyuki Konno
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Keisuke Yamamoto
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoshio Koyanagi
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Kei Sato
- Laboratory of Systems Virology, Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,CREST, Japan Science and Technology Agency, Kawaguchi, Japan
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36
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Zhang Z, Gu Q, de Manuel Montero M, Bravo IG, Marques-Bonet T, Häussinger D, Münk C. Stably expressed APOBEC3H forms a barrier for cross-species transmission of simian immunodeficiency virus of chimpanzee to humans. PLoS Pathog 2017; 13:e1006746. [PMID: 29267382 PMCID: PMC5739507 DOI: 10.1371/journal.ppat.1006746] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 11/12/2017] [Indexed: 02/07/2023] Open
Abstract
APOBEC3s (A3s) are potent restriction factors of human immunodeficiency virus type 1/simian immunodeficiency viruses (HIV-1/SIV), and can repress cross-species transmissions of lentiviruses. HIV-1 originated from a zoonotic infection of SIV of chimpanzee (SIVcpz) to humans. However, the impact of human A3s on the replication of SIVcpz remains unclear. By using novel SIVcpz reporter viruses, we identified that human APOBEC3B (A3B) and APOBEC3H (A3H) haplotype II strongly reduced the infectivity of SIVcpz, because both of them are resistant to SIVcpz Vifs. We further demonstrated that human A3H inhibited SIVcpz by deaminase dependent as well independent mechanisms. In addition, other stably expressed human A3H haplotypes and splice variants showed strong antiviral activity against SIVcpz. Moreover, most SIV and HIV lineage Vif proteins could degrade chimpanzee A3H, but no Vifs from SIVcpz and SIV of gorilla (SIVgor) lineages antagonized human A3H haplotype II. Expression of human A3H hapII in human T cells efficiently blocked the spreading replication of SIVcpz. The spreading replication of SIVcpz was also restricted by stable A3H in human PBMCs. Thus, we speculate that stably expressed human A3H protects humans against the cross-species transmission of SIVcpz and that SIVcpz spillover to humans may have started in individuals that harbor haplotypes of unstable A3H proteins.
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Affiliation(s)
- Zeli Zhang
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Qinyong Gu
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | | | | | - Tomas Marques-Bonet
- Institut Biologia Evolutiva (Universitat Pompeu Fabra/CSIC) ICREA, Barcelona, Spain
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Carsten Münk
- Clinic for Gastroenterology, Hepatology, and Infectiology, Medical Faculty, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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37
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Adolph MB, Ara A, Feng Y, Wittkopp CJ, Emerman M, Fraser JS, Chelico L. Cytidine deaminase efficiency of the lentiviral viral restriction factor APOBEC3C correlates with dimerization. Nucleic Acids Res 2017; 45:3378-3394. [PMID: 28158858 PMCID: PMC5389708 DOI: 10.1093/nar/gkx066] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 01/24/2017] [Indexed: 01/28/2023] Open
Abstract
The seven APOBEC3 (A3) enzymes in primates restrict HIV/SIV replication to differing degrees by deaminating cytosine in viral (−)DNA, which forms promutagenic uracils that inactivate the virus. A polymorphism in human APOBEC3C (A3C) that encodes an S188I mutation increases the enzymatic activity of the protein and its ability to restrict HIV-1, and correlates with increased propensity to form dimers. However, other hominid A3C proteins only have an S188, suggesting they should be less active like the common form of human A3C. Nonetheless, here we demonstrate that chimpanzee and gorilla A3C have approximately equivalent activity to human A3C I188 and that chimpanzee and gorilla A3C form dimers at the same interface as human A3C S188I, but through different amino acids. For each of these hominid A3C enzymes, dimerization enables processivity on single-stranded DNA and results in higher levels of mutagenesis during reverse transcription in vitro and in cells. For increased mutagenic activity, formation of a dimer was more important than specific amino acids and the dimer interface is unique from other A3 enzymes. We propose that dimerization is a predictor of A3C enzyme activity.
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Affiliation(s)
- Madison B Adolph
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Anjuman Ara
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Yuqing Feng
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Cristina J Wittkopp
- Department of Microbiology, University of Washington, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Michael Emerman
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - James S Fraser
- Department of Bioengineering and Therapeutic Science and California Institute for Quantitative Biology, University of California, San Francisco, San Francisco, CA, USA
| | - Linda Chelico
- Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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38
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Bell SM, Bedford T. Modern-day SIV viral diversity generated by extensive recombination and cross-species transmission. PLoS Pathog 2017; 13:e1006466. [PMID: 28672035 PMCID: PMC5510905 DOI: 10.1371/journal.ppat.1006466] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 07/14/2017] [Accepted: 06/12/2017] [Indexed: 02/04/2023] Open
Abstract
Cross-species transmission (CST) has led to many devastating epidemics, but is still a poorly understood phenomenon. HIV-1 and HIV-2 (human immunodeficiency virus 1 and 2), which have collectively caused over 35 million deaths, are the result of multiple CSTs from chimpanzees, gorillas, and sooty mangabeys. While the immediate history of HIV is known, there are over 45 lentiviruses that infect specific species of primates, and patterns of host switching are not well characterized. We thus took a phylogenetic approach to better understand the natural history of SIV recombination and CST. We modeled host species as a discrete character trait on the viral phylogeny and inferred historical host switches and the pairwise transmission rates between each pair of 24 primate hosts. We identify 14 novel, well-supported, ancient cross-species transmission events. We also find that lentiviral lineages vary widely in their ability to infect new host species: SIVcol (from colobus monkeys) is evolutionarily isolated, while SIVagms (from African green monkeys) frequently move between host subspecies. We also examine the origins of SIVcpz (the predecessor of HIV-1) in greater detail than previous studies, and find that there are still large portions of the genome with unknown origins. Observed patterns of CST are likely driven by a combination of ecological circumstance and innate immune factors.
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Affiliation(s)
- Sidney M. Bell
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Molecular and Cellular Biology Program, University of Washington, Seattle, Washington, United States of America
- * E-mail:
| | - Trevor Bedford
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
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39
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The KT Jeang Retrovirology prize 2017: Michael Emerman. Retrovirology 2017. [PMID: 28637466 PMCID: PMC5480113 DOI: 10.1186/s12977-017-0362-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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40
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Yamamoto M, Koga R, Fujino H, Shimagaki K, Ciftci HI, Kamo M, Tateishi H, Otsuka M, Fujita M. Zinc-binding site of human immunodeficiency virus 2 Vpx prevents instability and dysfunction of the protein. J Gen Virol 2017; 98:275-283. [DOI: 10.1099/jgv.0.000701] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Minami Yamamoto
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Ryoko Koga
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Haruna Fujino
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Kazunori Shimagaki
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Halil Ibrahim Ciftci
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Masahiro Kamo
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Hiroshi Tateishi
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Masami Otsuka
- Department of Bioorganic Medicinal Chemistry, Faculty of Life Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Mikako Fujita
- Research Institute for Drug Discovery, School of Pharmacy, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
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41
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González ME. The HIV-1 Vpr Protein: A Multifaceted Target for Therapeutic Intervention. Int J Mol Sci 2017; 18:ijms18010126. [PMID: 28075409 PMCID: PMC5297760 DOI: 10.3390/ijms18010126] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/22/2016] [Accepted: 01/03/2017] [Indexed: 12/16/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) Vpr protein is an attractive target for antiretroviral drug development. The conservation both of the structure along virus evolution and the amino acid sequence in viral isolates from patients underlines the importance of Vpr for the establishment and progression of HIV-1 disease. While its contribution to virus replication in dividing and non-dividing cells and to the pathogenesis of HIV-1 in many different cell types, both extracellular and intracellular forms, have been extensively studied, its precise mechanism of action nevertheless remains enigmatic. The present review discusses how the apparently multifaceted interplay between Vpr and host cells may be due to the impairment of basic metabolic pathways. Vpr protein modifies host cell energy metabolism, oxidative status, and proteasome function, all of which are likely conditioned by the concentration and multimerization of the protein. The characterization of Vpr domains along with new laboratory tools for the assessment of their function has become increasingly relevant in recent years. With these advances, it is conceivable that drug discovery efforts involving Vpr-targeted antiretrovirals will experience substantial growth in the coming years.
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Affiliation(s)
- María Eugenia González
- Unidad de Expresión Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Carretera de Majadahonda-Pozuelo Km 2, Majadahonda, 28220 Madrid, Spain.
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42
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Schott K, Riess M, König R. Role of Innate Genes in HIV Replication. Curr Top Microbiol Immunol 2017; 419:69-111. [PMID: 28685292 DOI: 10.1007/82_2017_29] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Cells use an elaborate innate immune surveillance and defense system against virus infections. Here, we discuss recent studies that reveal how HIV-1 is sensed by the innate immune system. Furthermore, we present mechanisms on the counteraction of HIV-1. We will provide an overview how HIV-1 actively utilizes host cellular factors to avoid sensing. Additionally, we will summarize effectors of the innate response that provide an antiviral cellular state. HIV-1 has evolved passive mechanism to avoid restriction and to regulate the innate response. We review in detail two prominent examples of these cellular factors: (i) NLRX1, a negative regulator of the innate response that HIV-1 actively usurps to block cytosolic innate sensing; (ii) SAMHD1, a restriction factor blocking the virus at the reverse transcription step that HIV-1 passively avoids to escape sensing.
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Affiliation(s)
- Kerstin Schott
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany
| | - Maximilian Riess
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany
| | - Renate König
- Host-Pathogen Interactions, Paul-Ehrlich-Institute, 63225, Langen, Germany. .,Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA. .,German Center for Infection Research (DZIF), 63225, Langen, Germany.
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43
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Stabell AC, Hawkins J, Li M, Gao X, David M, Press WH, Sawyer SL. Non-human Primate Schlafen11 Inhibits Production of Both Host and Viral Proteins. PLoS Pathog 2016; 12:e1006066. [PMID: 28027315 PMCID: PMC5189954 DOI: 10.1371/journal.ppat.1006066] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/15/2016] [Indexed: 11/18/2022] Open
Abstract
Schlafen11 (encoded by the SLFN11 gene) has been shown to inhibit the accumulation of HIV-1 proteins. We show that the SLFN11 gene is under positive selection in simian primates and is species-specific in its activity against HIV-1. The activity of human Schlafen11 is relatively weak compared to that of some other primate versions of this protein, with the versions encoded by chimpanzee, orangutan, gibbon, and marmoset being particularly potent inhibitors of HIV-1 protein production. Interestingly, we find that Schlafen11 is functional in the absence of infection and reduces protein production from certain non-viral (GFP) and even host (Vinculin and GAPDH) transcripts. This suggests that Schlafen11 may just generally block protein production from non-codon optimized transcripts. Because Schlafen11 is an interferon-stimulated gene with a broad ability to inhibit protein production from many host and viral transcripts, its role may be to create a general antiviral state in the cell. Interestingly, the strong inhibitors such as marmoset Schlafen11 consistently block protein production better than weak primate Schlafen11 proteins, regardless of the virus or host target being analyzed. Further, we show that the residues to which species-specific differences in Schlafen11 potency map are distinct from residues that have been targeted by positive selection. We speculate that the positive selection of SLFN11 could have been driven by a number of different factors, including interaction with one or more viral antagonists that have yet to be identified. Schlafen11 was recently identified as a human antiviral protein with activity against HIV-1. Here we show that some nonhuman primate versions of Schlafen11 are much stronger at blocking the accumulation of viral proteins than is human Schlafen11. These relatively larger phenotypes of nonhuman primate Schlafen11 allowed us to explore further into the mechanism of this protein. We present data showing that Schlafen11 may not be a classic restriction factor, but rather an interferon-stimulated gene with broad ability to inhibit protein production from many host and viral transcripts, creating a general antiviral state in the cell.
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Affiliation(s)
- Alex C. Stabell
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, United States of America
| | - John Hawkins
- Institute for Computational Engineering and Sciences, University of Texas at Austin, TX, United States of America
| | - Manqing Li
- Division of Biological Sciences, UCSD Moores Cancer Center, University of California San Diego, La Jolla, CA, United States of America
| | - Xia Gao
- Division of Biological Sciences, UCSD Moores Cancer Center, University of California San Diego, La Jolla, CA, United States of America
| | - Michael David
- Division of Biological Sciences, UCSD Moores Cancer Center, University of California San Diego, La Jolla, CA, United States of America
| | - William H. Press
- Institute for Computational Engineering and Sciences, University of Texas at Austin, TX, United States of America
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States of America
| | - Sara L. Sawyer
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, United States of America
- * E-mail:
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44
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Foley BT, Leitner T, Paraskevis D, Peeters M. Primate immunodeficiency virus classification and nomenclature: Review. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2016; 46:150-158. [PMID: 27789390 PMCID: PMC5136504 DOI: 10.1016/j.meegid.2016.10.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 10/19/2016] [Accepted: 10/21/2016] [Indexed: 12/25/2022]
Abstract
The International Committee for the Taxonomy and Nomenclature of Viruses does not rule on virus classifications below the species level. The definition of species for viruses cannot be clearly defined for all types of viruses. The complex and interesting epidemiology of Human Immunodeficiency Viruses demands a detailed and informative nomenclature system, while at the same time it presents challenges such that many of the rules need to be flexibly applied or modified over time. This review outlines the nomenclature system for primate lentiviruses and provides an update on new findings since the last review was written in 2000.
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Affiliation(s)
- Brian T Foley
- Theoretical Biology and Biophysics Group, T-6 Mail Stop K710, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Thomas Leitner
- Theoretical Biology and Biophysics Group, T-6 Mail Stop K710, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Dimitrios Paraskevis
- National and Kapodistrian University of Athens, Department of Hygiene, Epidemiology and Medical Statistics, Medical School, Athens, Greece
| | - Martine Peeters
- UMI233-TransVIHMI, Institut de Recherche pour le Développement (IRD), INSERM U1175, University of Montpellier, Montpellier, France; IBC, Computational Biology Institute, 34095 Montpellier, France
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45
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Abstract
PURPOSE OF REVIEW The goal of this review is to summarize recent progress in our understanding of innate sensing of HIV. Furthermore, we present the mechanisms that HIV has evolved to attenuate innate immune responses and discuss open questions. RECENT FINDINGS Toll-like receptors (TLRs) and various cytosolic sensors induce an antiviral interferon response upon detection of genomic HIV RNA or intermediates of reverse transcription. HIV limits activation of these sensing pathways by interfering with TLR signaling and by cloaking viral nucleic acids in the cytoplasm, before proviral dsDNA translocates into the nucleus. Furthermore, the viral accessory protein Vpu mitigates antiviral gene expression by inhibiting canonical nuclear factor kappa B (NF-κB) signaling. These evasion mechanisms, however, are imperfect and HIV infection almost inevitably triggers the activation of IRF3, NF-κB and other key transcription factors of antiviral immunity. Notably, the interplay of these processes plays a critical role in the induction of chronic inflammation that drives progression to AIDS. SUMMARY HIV has evolved sophisticated but imperfect mechanisms to evade and counteract innate sensing. Whether virus-induced immune activation represents merely a suboptimal adaptation of HIV to its human host or even facilitates HIV replication, for example by increasing the number of viral target cells, remains to be clarified.
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46
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Sakai Y, Miyake A, Doi N, Sasada H, Miyazaki Y, Adachi A, Nomaguchi M. Expression Profiles of Vpx/Vpr Proteins Are Co-related with the Primate Lentiviral Lineage. Front Microbiol 2016; 7:1211. [PMID: 27536295 PMCID: PMC4971069 DOI: 10.3389/fmicb.2016.01211] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/20/2016] [Indexed: 01/03/2023] Open
Abstract
Viruses of human immunodeficiency virus type 2 (HIV-2) and some simian immunodeficiency virus (SIV) lineages carry a unique accessory protein called Vpx. Vpx is essential or critical for viral replication in natural target cells such as macrophages and T lymphocytes. We have previously shown that a poly-proline motif (PPM) located at the C-terminal region of Vpx is required for its efficient expression in two strains of HIV-2 and SIVmac, and that the Vpx expression levels of the two clones are significantly different. Notably, the PPM sequence is conserved and confined to Vpx and Vpr proteins derived from certain lineages of HIV-2/SIVs. In this study, Vpx/Vpr proteins from diverse primate lentiviral lineages were experimentally and phylogenetically analyzed to obtain the general expression picture in cells. While both the level and PPM-dependency of Vpx/Vpr expression in transfected cells varied among viral strains, each viral group, based on Vpx/Vpr amino acid sequences, was found to exhibit a characteristic expression profile. Moreover, phylogenetic tree analyses on Gag and Vpx/Vpr proteins gave essentially the same results. Taken together, our study described here suggests that each primate lentiviral lineage may have developed a unique expression pattern of Vpx/Vpr proteins for adaptation to its hostile cellular and species environments in the process of viral evolution.
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Affiliation(s)
- Yosuke Sakai
- Department of Microbiology, Tokushima University Graduate School of Medical Science Tokushima, Japan
| | - Ariko Miyake
- Laboratory of Molecular Immunology and Infectious Disease, Joint Faculty of Veterinary Medicine, Yamaguchi University Yamaguchi, Japan
| | - Naoya Doi
- Department of Microbiology, Tokushima University Graduate School of Medical Science Tokushima, Japan
| | - Hikari Sasada
- Department of Microbiology, Tokushima University Graduate School of Medical Science Tokushima, Japan
| | - Yasuyuki Miyazaki
- Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science Tokyo, Japan
| | - Akio Adachi
- Department of Microbiology, Tokushima University Graduate School of Medical Science Tokushima, Japan
| | - Masako Nomaguchi
- Department of Microbiology, Tokushima University Graduate School of Medical Science Tokushima, Japan
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47
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Matheson NJ, Greenwood EJ, Lehner PJ. Manipulation of immunometabolism by HIV-accessories to the crime? Curr Opin Virol 2016; 19:65-70. [PMID: 27448768 DOI: 10.1016/j.coviro.2016.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 06/17/2016] [Accepted: 06/29/2016] [Indexed: 10/21/2022]
Abstract
Evolutionary pressure has produced an 'arms race' between cellular restriction factors (limiting viral replication) and viral proteins (overcoming host restriction). The host factors SAMHD1 and SLFN1 patrol metabolic bottlenecks required for HIV replication. Conversely, the HIV accessory proteins Vpx, Vpu and Nef manipulate cellular metabolism to enable viral replication. Recent work identifying Vpu-mediated downregulation of the alanine transporter SNAT1 and Nef-mediated downregulation of the serine carriers SERINC3/5 has uncovered the importance of HIV manipulation of the amino acid supply. Interference with CD4(+) T-cell amino acid metabolism suggests a novel paradigm of viral immunomodulation, and signposts fundamental aspects of lymphocyte biology.
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Affiliation(s)
- Nicholas J Matheson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0XY, UK.
| | - Edward Jd Greenwood
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0XY, UK
| | - Paul J Lehner
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Cambridge CB2 0XY, UK.
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48
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Luo Y, Jacobs EY, Greco TM, Mohammed KD, Tong T, Keegan S, Binley JM, Cristea IM, Fenyö D, Rout MP, Chait BT, Muesing MA. HIV-host interactome revealed directly from infected cells. Nat Microbiol 2016; 1:16068. [PMID: 27375898 PMCID: PMC4928716 DOI: 10.1038/nmicrobiol.2016.68] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 04/16/2016] [Indexed: 01/27/2023]
Abstract
Although genetically compact, HIV-1 commandeers vast arrays of cellular machinery to sustain and protect it during cycles of viral outgrowth. Transposon-mediated saturation linker scanning mutagenesis was used to isolate fully replication-competent viruses harbouring a potent foreign epitope tag. Using these viral isolates, we performed differential isotopic labelling and affinity-capture mass spectrometric analyses on samples obtained from cultures of human lymphocytes to classify the vicinal interactomes of the viral Env and Vif proteins as they occur during natural infection. Importantly, interacting proteins were recovered without bias, regardless of their potential for positive, negative or neutral impact on viral replication. We identified specific host associations made with trimerized Env during its biosynthesis, at virological synapses, with innate immune effectors (such as HLA-E) and with certain cellular signalling pathways (for example, Notch1). We also defined Vif associations with host proteins involved in the control of nuclear transcription and nucleoside biosynthesis as well as those interacting stably or transiently with the cytoplasmic protein degradation apparatus. Our approach is broadly applicable to elucidating pathogen-host interactomes, providing high-certainty identification of interactors by their direct access during cycling infection. Understanding the pathophysiological consequences of these associations is likely to provide strategic targets for antiviral intervention.
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Affiliation(s)
- Yang Luo
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
| | - Erica Y. Jacobs
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Todd M. Greco
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08540, USA
| | - Kevin D. Mohammed
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
| | - Tommy Tong
- San Diego Biomedical Research Institute, 10865 Road to the Cure, San Diego, California 92121, USA
| | - Sarah Keegan
- Department of Biochemistry, New York University Langone Medical Center, 227 East 30th Street, New York, New York 10016, USA
| | - James M. Binley
- San Diego Biomedical Research Institute, 10865 Road to the Cure, San Diego, California 92121, USA
| | - Ileana M. Cristea
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08540, USA
| | - David Fenyö
- Department of Biochemistry, New York University Langone Medical Center, 227 East 30th Street, New York, New York 10016, USA
| | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Brian T. Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Mark A. Muesing
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
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49
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HIV-1 and HIV-2 exhibit divergent interactions with HLTF and UNG2 DNA repair proteins. Proc Natl Acad Sci U S A 2016; 113:E3921-30. [PMID: 27335459 DOI: 10.1073/pnas.1605023113] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HIV replication in nondividing host cells occurs in the presence of high concentrations of noncanonical dUTP, apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3 (APOBEC3) cytidine deaminases, and SAMHD1 (a cell cycle-regulated dNTP triphosphohydrolase) dNTPase, which maintains low concentrations of canonical dNTPs in these cells. These conditions favor the introduction of marks of DNA damage into viral cDNA, and thereby prime it for processing by DNA repair enzymes. Accessory protein Vpr, found in all primate lentiviruses, and its HIV-2/simian immunodeficiency virus (SIV) SIVsm paralogue Vpx, hijack the CRL4(DCAF1) E3 ubiquitin ligase to alleviate some of these conditions, but the extent of their interactions with DNA repair proteins has not been thoroughly characterized. Here, we identify HLTF, a postreplication DNA repair helicase, as a common target of HIV-1/SIVcpz Vpr proteins. We show that HIV-1 Vpr reprograms CRL4(DCAF1) E3 to direct HLTF for proteasome-dependent degradation independent from previously reported Vpr interactions with base excision repair enzyme uracil DNA glycosylase (UNG2) and crossover junction endonuclease MUS81, which Vpr also directs for degradation via CRL4(DCAF1) E3. Thus, separate functions of HIV-1 Vpr usurp CRL4(DCAF1) E3 to remove key enzymes in three DNA repair pathways. In contrast, we find that HIV-2 Vpr is unable to efficiently program HLTF or UNG2 for degradation. Our findings reveal complex interactions between HIV-1 and the DNA repair machinery, suggesting that DNA repair plays important roles in the HIV-1 life cycle. The divergent interactions of HIV-1 and HIV-2 with DNA repair enzymes and SAMHD1 imply that these viruses use different strategies to guard their genomes and facilitate their replication in the host.
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50
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Abstract
The enzyme reverse transcriptase (RT) was discovered in retroviruses almost 50 years ago. The demonstration that other types of viruses, and what are now called retrotransposons, also replicated using an enzyme that could copy RNA into DNA came a few years later. The intensity of the research in both the process of reverse transcription and the enzyme RT was greatly stimulated by the recognition, in the mid-1980s, that human immunodeficiency virus (HIV) was a retrovirus and by the fact that the first successful anti-HIV drug, azidothymidine (AZT), is a substrate for RT. Although AZT monotherapy is a thing of the past, the most commonly prescribed, and most successful, combination therapies still involve one or both of the two major classes of anti-RT drugs. Although the basic mechanics of reverse transcription were worked out many years ago, and the first high-resolution structures of HIV RT are now more than 20 years old, we still have much to learn, particularly about the roles played by the host and viral factors that make the process of reverse transcription much more efficient in the cell than in the test tube. Moreover, we are only now beginning to understand how various host factors that are part of the innate immunity system interact with the process of reverse transcription to protect the host-cell genome, the host cell, and the whole host, from retroviral infection, and from unwanted retrotransposition.
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