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Khan N, Geiger JD. Role of Viral Protein U (Vpu) in HIV-1 Infection and Pathogenesis. Viruses 2021; 13:v13081466. [PMID: 34452331 PMCID: PMC8402909 DOI: 10.3390/v13081466] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/16/2021] [Accepted: 07/24/2021] [Indexed: 12/11/2022] Open
Abstract
Human immunodeficiency virus (HIV)-1 and HIV-2 originated from cross-species transmission of simian immunodeficiency viruses (SIVs). Most of these transfers resulted in limited spread of these viruses to humans. However, one transmission event involving SIVcpz from chimpanzees gave rise to group M HIV-1, with M being the principal strain of HIV-1 responsible for the AIDS pandemic. Vpu is an HIV-1 accessory protein generated from Env/Vpu encoded bicistronic mRNA and localized in cytosolic and membrane regions of cells capable of being infected by HIV-1 and that regulate HIV-1 infection and transmission by downregulating BST-2, CD4 proteins levels, and immune evasion. This review will focus of critical aspects of Vpu including its zoonosis, the adaptive hurdles to cross-species transmission, and future perspectives and broad implications of Vpu in HIV-1 infection and dissemination.
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Schmitt K, Curlin J, Remling-Mulder L, Moriarty R, Goff K, O'Connor S, Stenglein M, Marx P, Akkina R. Cross-Species Transmission and Evolution of SIV Chimpanzee Progenitor Viruses Toward HIV-1 in Humanized Mice. Front Microbiol 2020; 11:1889. [PMID: 32849468 PMCID: PMC7432304 DOI: 10.3389/fmicb.2020.01889] [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: 05/22/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022] Open
Abstract
The genetic evolution of HIV-1 from its progenitor virus SIV following cross-species transmission is not well understood. Here we simulated the SIVcpz initial transmission to humans using humanized mice and followed the viral evolution during serial passages lasting more than a year. All three SIVcpz progenitor viruses used, namely LB715 and MB897 (group M) as well as EK505 (group N) readily infected hu-mice resulting in chronic viremia. Viral loads increased progressively to higher set-points and the CD4+ T cell decline became more pronounced by the end of the second serial passage indicating viral adaptation and increased pathogenicity. Viral genomes sequenced at different time points revealed many non-synonymous variants not previously reported that occurred throughout the viral genome, including the gag, pol, env, and nef genes. These results shed light on the potential changes that the SIVcpz genome had undergone during the initial stages of human infection and subsequent spread.
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Affiliation(s)
- Kimberly Schmitt
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - James Curlin
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Leila Remling-Mulder
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Ryan Moriarty
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Kelly Goff
- Tulane National Primate Research Center, Tulane University, Covington, LA, United States
| | - Shelby O'Connor
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, United States
| | - Mark Stenglein
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Preston Marx
- Tulane National Primate Research Center, Tulane University, Covington, LA, United States.,Department of Tropical Medicine, School of Public Health & Tropical Medicine, Tulane University, New Orleans, LA, United States
| | - Ramesh Akkina
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, United States
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3
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Hopfensperger K, Richard J, Stürzel CM, Bibollet-Ruche F, Apps R, Leoz M, Plantier JC, Hahn BH, Finzi A, Kirchhoff F, Sauter D. Convergent Evolution of HLA-C Downmodulation in HIV-1 and HIV-2. mBio 2020; 11:e00782-20. [PMID: 32665270 PMCID: PMC7360927 DOI: 10.1128/mbio.00782-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/11/2020] [Indexed: 12/13/2022] Open
Abstract
HLA-C-mediated antigen presentation induces the killing of human immunodeficiency virus (HIV)-infected CD4+ T cells by cytotoxic T lymphocytes (CTLs). To evade killing, many HIV-1 group M strains decrease HLA-C surface levels using their accessory protein Vpu. However, some HIV-1 group M isolates lack this activity, possibly to prevent the activation of natural killer (NK) cells. Analyzing diverse primate lentiviruses, we found that Vpu-mediated HLA-C downregulation is not limited to pandemic group M but is also found in HIV-1 groups O and P as well as several simian immunodeficiency viruses (SIVs). We show that Vpu targets HLA-C primarily at the protein level, independently of its ability to suppress NF-κB-driven gene expression, and that in some viral lineages, HLA-C downregulation may come at the cost of efficient counteraction of the restriction factor tetherin. Remarkably, HIV-2, which does not carry a vpu gene, uses its accessory protein Vif to decrease HLA-C surface expression. This Vif activity requires intact binding sites for the Cullin5/Elongin ubiquitin ligase complex but is separable from its ability to counteract APOBEC3G. Similar to HIV-1 Vpu, the degree of HIV-2 Vif-mediated HLA-C downregulation varies considerably among different virus isolates. In agreement with opposing selection pressures in vivo, we show that the reduction of HLA-C surface levels by HIV-2 Vif is accompanied by increased NK cell-mediated killing. In summary, our results highlight the complex role of HLA-C in lentiviral infections and demonstrate that HIV-1 and HIV-2 have evolved at least two independent mechanisms to decrease HLA-C levels on infected cells.IMPORTANCE Genome-wide association studies suggest that HLA-C expression is a major determinant of viral load set points and CD4+ T cell counts in HIV-infected individuals. On the one hand, efficient HLA-C expression enables the killing of infected cells by cytotoxic T lymphocytes (CTLs). On the other hand, HLA-C sends inhibitory signals to natural killer (NK) cells and enhances the infectivity of newly produced HIV particles. HIV-1 group M viruses modulate HLA-C expression using the accessory protein Vpu, possibly to balance CTL- and NK cell-mediated immune responses. Here, we show that the second human immunodeficiency virus, HIV-2, can use its accessory protein Vif to evade HLA-C-mediated restriction. Furthermore, our mutational analyses provide insights into the underlying molecular mechanisms. In summary, our results reveal how the two human AIDS viruses modulate HLA-C, a key component of the antiviral immune response.
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Affiliation(s)
| | - Jonathan Richard
- Centre de Recherche du CHUM, Montreal, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Canada
| | - Christina M Stürzel
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Frederic Bibollet-Ruche
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Richard Apps
- NIH Center for Human Immunology, National Institutes of Health, Bethesda, Maryland, USA
| | - Marie Leoz
- Normandie Université, UNIROUEN, UNICAEN, GRAM 2.0, Rouen, France
| | - Jean-Christophe Plantier
- Normandie Université, UNIROUEN, UNICAEN, GRAM 2.0, Rouen University Hospital, Department of Virology, Laboratory Associated with the National Reference Center on HIV, Rouen, France
| | - Beatrice H Hahn
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, Canada
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
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4
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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: 11] [Impact Index Per Article: 2.8] [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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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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Yamada E, Nakaoka S, Klein L, Reith E, Langer S, Hopfensperger K, Iwami S, Schreiber G, Kirchhoff F, Koyanagi Y, Sauter D, Sato K. Human-Specific Adaptations in Vpu Conferring Anti-tetherin Activity Are Critical for Efficient Early HIV-1 Replication In Vivo. Cell Host Microbe 2018; 23:110-120.e7. [PMID: 29324226 DOI: 10.1016/j.chom.2017.12.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 09/11/2017] [Accepted: 12/01/2017] [Indexed: 12/24/2022]
Abstract
The HIV-1-encoded accessory protein Vpu exerts several immunomodulatory functions, including counteraction of the host restriction factor tetherin, downmodulation of CD4, and inhibition of NF-κB activity to facilitate HIV-1 infection. However, the relative contribution of individual Vpu functions to HIV-1 infection in vivo remained unclear. Here, we used a humanized mouse model and HIV-1 strains with selective mutations in vpu to demonstrate that the anti-tetherin activity of Vpu is a prerequisite for efficient viral spread during the early phase of infection. Mathematical modeling and gain-of-function mutations in SIVcpz, the simian precursor of pandemic HIV-1, corroborate this finding. Blockage of interferon signaling combined with transcriptome analyses revealed that basal tetherin levels are sufficient to control viral replication. These results establish tetherin as a key effector of the intrinsic immune defense against HIV-1, and they demonstrate that Vpu-mediated tetherin antagonism is critical for efficient viral spread during the initial phase of HIV-1 replication.
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Affiliation(s)
- Eri Yamada
- Laboratory of Systems Virology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 6068507, Japan
| | - Shinji Nakaoka
- Institute of Industrial Sciences, The University of Tokyo, Tokyo 1538505, Japan; PRESTO, Japan Science and Technology Agency, Saitama 3320012, Japan
| | - Lukas Klein
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Elisabeth Reith
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Simon Langer
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | | | - Shingo Iwami
- PRESTO, Japan Science and Technology Agency, Saitama 3320012, Japan; CREST, Japan Science and Technology Agency, Saitama 3220012, Japan; Department of Biology, Faculty of Sciences, Kyushu University, Fukuoka 8128581, Japan
| | - Gideon Schreiber
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Yoshio Koyanagi
- Laboratory of Systems Virology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 6068507, Japan
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, Ulm 89081, Germany
| | - Kei Sato
- Laboratory of Systems Virology, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto 6068507, Japan; CREST, Japan Science and Technology Agency, Saitama 3220012, Japan.
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7
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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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8
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Foster TL, Pickering S, Neil SJD. Inhibiting the Ins and Outs of HIV Replication: Cell-Intrinsic Antiretroviral Restrictions at the Plasma Membrane. Front Immunol 2018; 8:1853. [PMID: 29354117 PMCID: PMC5758531 DOI: 10.3389/fimmu.2017.01853] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 12/07/2017] [Indexed: 01/01/2023] Open
Abstract
Like all viruses, human immunodeficiency viruses (HIVs) and their primate lentivirus relatives must enter cells in order to replicate and, once produced, new virions need to exit to spread to new targets. These processes require the virus to cross the plasma membrane of the cell twice: once via fusion mediated by the envelope glycoprotein to deliver the viral core into the cytosol; and secondly by ESCRT-mediated scission of budding virions during release. This physical barrier thus presents a perfect location for host antiviral restrictions that target enveloped viruses in general. In this review we will examine the current understanding of innate host antiviral defences that inhibit these essential replicative steps of primate lentiviruses associated with the plasma membrane, the mechanism by which these viruses have adapted to evade such defences, and the role that this virus/host battleground plays in the transmission and pathogenesis of HIV/AIDS.
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Affiliation(s)
- Toshana L Foster
- Department of Infectious Disease, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Suzanne Pickering
- Department of Infectious Disease, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
| | - Stuart J D Neil
- Department of Infectious Disease, School of Immunology and Microbial Sciences, King's College London, London, United Kingdom
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9
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Mack K, Starz K, Sauter D, Langer S, Bibollet-Ruche F, Learn GH, Stürzel CM, Leoz M, Plantier JC, Geyer M, Hahn BH, Kirchhoff F. Efficient Vpu-Mediated Tetherin Antagonism by an HIV-1 Group O Strain. J Virol 2017; 91:e02177-16. [PMID: 28077643 PMCID: PMC5331793 DOI: 10.1128/jvi.02177-16] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 12/22/2016] [Indexed: 11/20/2022] Open
Abstract
Simian immunodeficiency viruses (SIVs) use their Nef proteins to counteract the restriction factor tetherin. However, a deletion in human tetherin prevents antagonism by the Nef proteins of SIVcpz and SIVgor, which represent the ape precursors of human immunodeficiency virus type 1 (HIV-1). To promote virus release from infected cells, pandemic HIV-1 group M strains evolved Vpu as a tetherin antagonist, while the Nef protein of less widespread HIV-1 group O strains acquired the ability to target a region adjacent to this deletion. In this study, we identified an unusual HIV-1 group O strain (RBF206) that evolved Vpu as an effective antagonist of human tetherin. While both RBF206 Vpu and Nef exert anti-tetherin activity in transient-transfection assays, mainly Vpu promotes RBF206 release in infected CD4+ T cells. Although mutations distinct from the adaptive changes observed in group M Vpus (M-Vpus) were critical for the acquisition of its anti-tetherin activity, RBF206 O-Vpu potently suppresses NF-κB activation and reduces CD4 cell surface expression. Interestingly, RBF206 Vpu counteracts tetherin in a largely species-independent manner, degrading both the long and short isoforms of human tetherin. Downmodulation of CD4, but not counteraction of tetherin, by RBF206 Vpu was dependent on the cellular ubiquitin ligase machinery. Our data present the first example of an HIV-1 group O Vpu that efficiently antagonizes human tetherin and suggest that counteraction by O-Nefs may be suboptimal.IMPORTANCE Previous studies showed that HIV-1 groups M and O evolved two alternative strategies to counteract the human ortholog of the restriction factor tetherin. While HIV-1 group M switched from Nef to Vpu due to a deletion in the cytoplasmic domain of human tetherin, HIV-1 group O, which lacks Vpu-mediated anti-tetherin activity, acquired a Nef protein that is able to target a region adjacent to the deletion. Here we report an unusual exception, identifying a strain of HIV-1 group O (RBF206) whose Vpu protein evolved an effective antagonism of human tetherin. Interestingly, the adaptive changes in RBF206 Vpu are distinct from those found in M-Vpus and mediate efficient counteraction of both the long and short isoforms of this restriction factor. Our results further illustrate the enormous flexibility of HIV-1 in counteracting human defense mechanisms.
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Affiliation(s)
- Katharina Mack
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Kathrin Starz
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Simon Langer
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | | | - Gerald H Learn
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Christina M Stürzel
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Marie Leoz
- Laboratoire de Virologie, CHU Charles Nicolle, Rouen, France
- EA 2656 GRAM Université de Rouen, Rouen, France
| | - Jean-Christophe Plantier
- Laboratoire de Virologie, CHU Charles Nicolle, Rouen, France
- EA 2656 GRAM Université de Rouen, Rouen, France
- Laboratoire associé au Centre National de Référence du VIH, CHU Charles Nicolle, Rouen, France
| | - Matthias Geyer
- Department of Structural Immunology, Institute of Innate Immunity, University of Bonn, Bonn, Germany
| | - Beatrice H Hahn
- Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
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10
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ISG15 expression correlates with HIV-1 viral load and with factors regulating T cell response. Immunobiology 2015; 221:282-90. [PMID: 26563749 DOI: 10.1016/j.imbio.2015.10.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 10/25/2015] [Indexed: 01/24/2023]
Abstract
Given the multifactorial nature of action of type I interferon (IFN) in HIV-1 infection and the need to firmly establish the action of key components of IFN pathways, we compared the IFN stimulated gene (ISG)15 expression with that of other well-characterized ISGs, evaluating its relationship with immunosuppressive factors regulating T-cell response in HIV-1 patients. PBMC from 225 subjects were included: healthy donors (n=30), naïve (n=93) and HAART treated HIV-1 subjects (n=102). Levels of ISG15-mRNA, ISG56-mRNA, APOBEC3G/3F-mRNA, TRAIL-mRNA, IDO-mRNA, proviral load andISG15 (rs15842 and rs1921) SNPs were evaluated by using TaqMan assays. We found that ISG15, ISG56, APOBEC3G/3F levels were increased in untreated HIV-1 patients compared to healthy donors, being ISG15 the highest ISG expressed. The amount of ISG15 correlated with viral load and with CD4+ T cell counts whereas no relationship was found between all ISGs analyzed and proviral load or HIV-1 tropism. ISG15 expression was reduced following long-term antiretroviral therapy. In addition, ISG15 levels were correlated with those of TRAIL and IDO in HIV-1 viremic patients. Lastly, ISG15 SNPs had no influence on ISG15 levels. We demonstrates that ISG15 is elevated in viremic HIV-1 patients and is associated with high TRAIL and IDO levels.
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11
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Simon V, Bloch N, Landau NR. Intrinsic host restrictions to HIV-1 and mechanisms of viral escape. Nat Immunol 2015; 16:546-53. [PMID: 25988886 PMCID: PMC6908429 DOI: 10.1038/ni.3156] [Citation(s) in RCA: 215] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 03/24/2015] [Indexed: 02/06/2023]
Abstract
To replicate in their hosts, viruses have to navigate the complexities of the mammalian cell, co-opting mechanisms of cellular physiology while defeating restriction factors that are dedicated to halting their progression. Primate lentiviruses devote a relatively large portion of their coding capacity to counteracting restriction factors by encoding accessory proteins dedicated to neutralizing the antiviral function of these intracellular inhibitors. Research into the roles of the accessory proteins has revealed the existence of previously undetected intrinsic defenses, provided insight into the evolution of primate lentiviruses as they adapt to new species and uncovered new targets for the development of therapeutics. This Review discusses the biology of the restriction factors APOBEC3, SAMHD1 and tetherin and the viral accessory proteins that counteract them.
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Affiliation(s)
- Viviana Simon
- Department of Microbiology, The Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nicolin Bloch
- Department of Microbiology, NYU School of Medicine, New York, New York, USA
| | - Nathaniel R Landau
- Department of Microbiology, NYU School of Medicine, New York, New York, USA
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12
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Sauter D. Counteraction of the multifunctional restriction factor tetherin. Front Microbiol 2014; 5:163. [PMID: 24782851 PMCID: PMC3989765 DOI: 10.3389/fmicb.2014.00163] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 03/26/2014] [Indexed: 01/28/2023] Open
Abstract
The interferon-inducible restriction factor tetherin (also known as CD317, BST-2 or HM1.24) has emerged as a key component of the antiviral immune response. Initially, tetherin was shown to restrict replication of various enveloped viruses by inhibiting the release of budding virions from infected cells. More recently, it has become clear that tetherin also acts as a pattern recognition receptor inducing NF-κB-dependent proinflammatory gene expression in virus infected cells. Whereas the ability to restrict virion release is highly conserved among mammalian tetherin orthologs and thus probably an ancient function of this protein, innate sensing seems to be an evolutionarily recent activity. The potent and broad antiviral activity of tetherin is reflected by the fact that many viruses evolved means to counteract this restriction factor. A continuous arms race with viruses has apparently driven the evolution of different isoforms of tetherin with different functional properties. Interestingly, tetherin has also been implicated in cellular processes that are unrelated to immunity, such as the organization of the apical actin network and membrane microdomains or stabilization of the Golgi apparatus. In this review, I summarize our current knowledge of the different functions of tetherin and describe the molecular strategies that viruses have evolved to antagonize or evade this multifunctional host restriction factor.
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Affiliation(s)
- Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center Ulm, Germany
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Skelton MM, Kampira EE, Wonkam AA, Mhandire KK, Kumwenda JJ, Duri KK, Dandara CC. Frequency variation among sub-Saharan populations in virus restriction gene, BST-2 proximal promoter polymorphisms: implications for HIV-1 prevalence differences among African countries. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2014; 18:461-71. [PMID: 24601767 DOI: 10.1089/omi.2013.0127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The present study reports promoter variants in four sub-Saharan African populations that may affect BST-2 gene regulation. Recently, an in/del within the BST-2 promoter has been associated with HIV-1 disease progression in a Spanish cohort. Hence, we sequenced the proximal promoter region of the BST-2 gene in 581 individuals from South Africa, Zimbabwe, Malawi, and Cameroon. Seven SNPs were identified: rs28413176 (+26i6/Δ6); rs28413175 (-160i1/Δ1), -187A>G (nucleotide position -17516614); rs28413174 (-193G>A); rs73921425 (-199G>A); rs12609479 (-201C>T); and rs112492472 (-225C>T). The -199A and -225T alleles showed interesting trends across the sub-Saharan continent. Using predictive bioinformatics tools, we show that allelic variation at -199 and -201 potentially affect key transcription factor binding sites including bHLH, c-Myb, and E47. Importantly, data available from the ENCODE study gave further credence to our hypothesis of transcriptional regulation of BST-2 by a bHLH TF such as Mxi1. The possible repressive transcriptional effect of Mxi1 combined with the allelic frequency trend seen at -199 between African populations overlays well with current HIV-1 prevalence data, and may be a contributing factor to this phenomenon. The differences in HIV-1 prevalence in African countries could be, in part, due to distribution of genetic variants that affect susceptibility to HIV-1. Our findings therefore have substantive value for the design of future diagnostics for global health oriented diagnostics for HIV-1 susceptibility, and rational therapeutics on the critical path to personalized medicine in the African continent. As HIV-1 epidemiology vastly impacts human populations around the world, the population genomics strategy we have utilized herein can have value for other global regions as well.
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Affiliation(s)
- Michelle M Skelton
- 1 Division of Human Genetics, Faculty of Health Sciences, University of Cape Town , Observatory, Cape Town, South Africa
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Li LH, Fischer WB. Correlation of biological activity with computationally derived structural features from transmembrane hetero-dimers of HIV-1 Vpu with host factors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:1104-12. [PMID: 24036078 DOI: 10.1016/j.bbamem.2013.07.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 07/26/2013] [Accepted: 07/31/2013] [Indexed: 01/29/2023]
Abstract
Vpu is an 81 amino acid type I integral membrane protein encoded by human immunodeficiency virus type 1 (HIV-1). It is identified to support viral release by potentially forming ion and substrate conducting channels and by modulating the function of host factors. The focus is on the interaction of the transmembrane domains of Vpu with those of host factors using a combination of molecular dynamics simulations and docking approach. Binding poses and adopted tilt angles of the dimers are analyzed and correlated with experimentally derived activity data from literature. Vpu activity is driven by dimerization with the host protein via its alanine rim Ala-8/11/15/19. Tight binding is shown by an almost parallel alignment of the helices in the dimers. Less parallel alignment is proposed to correlate with lower activity. This article is part of a Special Issue entitled: Viral Membrane Proteins - Channels for Cellular Networking.
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Affiliation(s)
- Li-Hua Li
- Institute of Biophotonics, School of Biomedical Science and Engineering, and Biophotonics & Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei 112, Taiwan
| | - Wolfgang B Fischer
- Institute of Biophotonics, School of Biomedical Science and Engineering, and Biophotonics & Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei 112, Taiwan.
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