1
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Gifford LB, Melikyan GB. HIV-1 Capsid Uncoating Is a Multistep Process That Proceeds through Defect Formation Followed by Disassembly of the Capsid Lattice. ACS NANO 2024; 18:2928-2947. [PMID: 38241476 PMCID: PMC10832047 DOI: 10.1021/acsnano.3c07678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 01/17/2024] [Accepted: 01/17/2024] [Indexed: 01/21/2024]
Abstract
The HIV-1 core consists of a cone-shaped capsid shell made of capsid protein (CA) hexamers and pentamers encapsulating the viral genome. HIV-1 capsid disassembly, referred to as uncoating, is important for productive infection; however, the location, timing, and regulation of uncoating remain controversial. Here, we employ amber codon suppression to directly label CA. In addition, a fluid phase fluorescent probe is incorporated into the viral core to detect small defects in the capsid lattice. This double-labeling strategy enables the visualization of uncoating of single cores in vitro and in living cells, which we found to always proceed through at least two distinct steps─the formation of a defect in the capsid lattice that initiates gradual loss of CA below a detectable level. Importantly, intact cores containing the fluid phase and CA fluorescent markers enter and uncoat in the nucleus, as evidenced by a sequential loss of both markers, prior to establishing productive infection. This two-step uncoating process is observed in different cells, including a macrophage line. Notably, the lag between the release of fluid phase marker and terminal loss of CA appears to be independent of the cell type or reverse transcription and is much longer (>5-fold) for nuclear capsids compared to cell-free cores or cores in the cytosol, suggesting that the capsid lattice is stabilized by capsid-binding nuclear factors. Our results imply that intact HIV-1 cores enter the cell nucleus and that uncoating is initiated through a localized defect in the capsid lattice prior to a global loss of CA.
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Affiliation(s)
- Levi B. Gifford
- Department
of Pediatrics, Emory University School of
Medicine, Atlanta, Georgia 30322, United States
| | - Gregory B. Melikyan
- Department
of Pediatrics, Emory University School of
Medicine, Atlanta, Georgia 30322, United States
- Children’s
Healthcare of Atlanta, Atlanta, Georgia 30322, United States
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2
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Dwivedi R, Prakash P, Kumbhar BV, Balasubramaniam M, Dash C. HIV-1 capsid and viral DNA integration. mBio 2024; 15:e0021222. [PMID: 38085100 PMCID: PMC10790781 DOI: 10.1128/mbio.00212-22] [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] [Indexed: 01/17/2024] Open
Abstract
IMPORTANCE HIV-1 capsid protein (CA)-independently or by recruiting host factors-mediates several key steps of virus replication in the cytoplasm and nucleus of the target cell. Research in the recent years have established that CA is multifunctional and genetically fragile of all the HIV-1 proteins. Accordingly, CA has emerged as a validated and high priority therapeutic target, and the first CA-targeting antiviral drug was recently approved for treating multi-drug resistant HIV-1 infection. However, development of next generation CA inhibitors depends on a better understanding of CA's known roles, as well as probing of CA's novel roles, in HIV-1 replication. In this timely review, we present an updated overview of the current state of our understanding of CA's multifunctional role in HIV-1 replication-with a special emphasis on CA's newfound post-nuclear roles, highlight the pressing knowledge gaps, and discuss directions for future research.
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Affiliation(s)
- Richa Dwivedi
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
| | - Prem Prakash
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Neuroscience and Pharmacology, Meharry Medical College, Nashville, Tennessee, USA
| | - Bajarang Vasant Kumbhar
- Department of Biological Sciences, Sunandan Divatia School of Science, NMIMS (Deemed to be) University, Mumbai, Maharashtra, India
| | - Muthukumar Balasubramaniam
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Neuroscience and Pharmacology, Meharry Medical College, Nashville, Tennessee, USA
| | - Chandravanu Dash
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Neuroscience and Pharmacology, Meharry Medical College, Nashville, Tennessee, USA
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3
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Gruenke PR, Mayer MD, Aneja R, Song Z, Burke DH, Heng X, Lange MJ. Differentiation SELEX approach identifies RNA aptamers with different specificities for HIV-1 capsid assembly forms. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.11.571135. [PMID: 38168417 PMCID: PMC10760009 DOI: 10.1101/2023.12.11.571135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The HIV-1 capsid protein (CA) assumes distinct assembly forms during replication, each presenting unique, solvent-accessible surfaces that facilitate multifaceted functions and host factor interactions. However, contributions of individual CA assemblies remain unclear, as the evaluation of CA in cells presents several technical challenges. To address this need, we sought to identify CA assembly form-specific aptamers. Aptamer subsets with different specificities emerged from within a highly converged, pre-enriched aptamer library previously selected to bind the CA hexamer lattice. Subsets were either highly specific for CA lattice or bound both CA lattice and CA hexamer. We further evaluated four representatives to reveal aptamer structural features required for binding, highlighting interesting features and challenges in aptamer structure determination. Importantly, our aptamers bind biologically relevant forms of CA and we demonstrate aptamer-mediated affinity purification of CA from cell lysates without virus or host modification. Thus, we have identified CA assembly form-specific aptamers that represent exciting new tools for the study of CA.
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4
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Padron A, Prakash P, Pandhare J, Luban J, Aiken C, Balasubramaniam M, Dash C. Emerging role of cyclophilin A in HIV-1 infection: from producer cell to the target cell nucleus. J Virol 2023; 97:e0073223. [PMID: 37843371 PMCID: PMC10688351 DOI: 10.1128/jvi.00732-23] [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: 10/17/2023] Open
Abstract
The HIV-1 genome encodes a small number of proteins with structural, enzymatic, regulatory, and accessory functions. These viral proteins interact with a number of host factors to promote the early and late stages of HIV-1 infection. During the early stages of infection, interactions between the viral proteins and host factors enable HIV-1 to enter the target cell, traverse the cytosol, dock at the nuclear pore, gain access to the nucleus, and integrate into the host genome. Similarly, the viral proteins recruit another set of host factors during the late stages of infection to orchestrate HIV-1 transcription, translation, assembly, and release of progeny virions. Among the host factors implicated in HIV-1 infection, Cyclophilin A (CypA) was identified as the first host factor to be packaged within HIV-1 particles. It is now well established that CypA promotes HIV-1 infection by directly binding to the viral capsid. Mechanistic models to pinpoint CypA's role have spanned from an effect in the producer cell to the early steps of infection in the target cell. In this review, we will describe our understanding of the role(s) of CypA in HIV-1 infection, highlight the current knowledge gaps, and discuss the potential role of this host factor in the post-nuclear entry steps of HIV-1 infection.
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Affiliation(s)
- Adrian Padron
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
- School of Graduate Studies, Meharry Medical College, Nashville, Tennessee, USA
| | - Prem Prakash
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Jui Pandhare
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
- School of Graduate Studies, Meharry Medical College, Nashville, Tennessee, USA
| | - Jeremy Luban
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Chris Aiken
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Muthukumar Balasubramaniam
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Chandravanu Dash
- The Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
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5
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HIV-1 Preintegration Complex Preferentially Integrates the Viral DNA into Nucleosomes Containing Trimethylated Histone 3-Lysine 36 Modification and Flanking Linker DNA. J Virol 2022; 96:e0101122. [PMID: 36094316 PMCID: PMC9517705 DOI: 10.1128/jvi.01011-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
HIV-1 DNA is preferentially integrated into chromosomal hot spots by the preintegration complex (PIC). To understand the mechanism, we measured the DNA integration activity of PICs-extracted from infected cells-and intasomes, biochemically assembled PIC substructures using a number of relevant target substrates. We observed that PIC-mediated integration into human chromatin is preferred compared to genomic DNA. Surprisingly, nucleosomes lacking histone modifications were not preferred integration compared to the analogous naked DNA. Nucleosomes containing the trimethylated histone 3 lysine 36 (H3K36me3), an epigenetic mark linked to active transcription, significantly stimulated integration, but the levels remained lower than the naked DNA. Notably, H3K36me3-modified nucleosomes with linker DNA optimally supported integration mediated by the PIC but not by the intasome. Interestingly, optimal intasome-mediated integration required the cellular cofactor LEDGF. Unexpectedly, LEDGF minimally affected PIC-mediated integration into naked DNA but blocked integration into nucleosomes. The block for the PIC-mediated integration was significantly relieved by H3K36me3 modification. Mapping the integration sites in the preferred substrates revealed that specific features of the nucleosome-bound DNA are preferred for integration, whereas integration into naked DNA was random. Finally, biochemical and genetic studies demonstrate that DNA condensation by the H1 protein dramatically reduces integration, providing further evidence that features inherent to the open chromatin are preferred for HIV-1 integration. Collectively, these results identify the optimal target substrate for HIV-1 integration, report a mechanistic link between H3K36me3 and integration preference, and importantly, reveal distinct mechanisms utilized by the PIC for integration compared to the intasomes. IMPORTANCE HIV-1 infection is dependent on integration of the viral DNA into the host chromosomes. The preintegration complex (PIC) containing the viral DNA, the virally encoded integrase (IN) enzyme, and other viral/host factors carries out HIV-1 integration. HIV-1 integration is not dependent on the target DNA sequence, and yet the viral DNA is selectively inserted into specific "hot spots" of human chromosomes. A growing body of literature indicates that structural features of the human chromatin are important for integration targeting. However, the mechanisms that guide the PIC and enable insertion of the PIC-associated viral DNA into specific hot spots of the human chromosomes are not fully understood. In this study, we describe a biochemical mechanism for the preference of the HIV-1 DNA integration into open chromatin. Furthermore, our study defines a direct role for the histone epigenetic mark H3K36me3 in HIV-1 integration preference and identify an optimal substrate for HIV-1 PIC-mediated viral DNA integration.
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6
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Identification of 2-(4-N,N-Dimethylaminophenyl)-5-methyl-1-phenethyl-1H-benzimidazole targeting HIV-1 CA capsid protein and inhibiting HIV-1 replication in cellulo. BMC Pharmacol Toxicol 2022; 23:43. [PMID: 35765101 PMCID: PMC9241302 DOI: 10.1186/s40360-022-00581-7] [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: 11/12/2021] [Accepted: 05/30/2022] [Indexed: 11/29/2022] Open
Abstract
The capsid (CA) subunit of the HIV-1 Gag polyprotein is involved in several steps of the viral cycle, from the assembly of new viral particles to the protection of the viral genome until it enters into the nucleus of newly infected cells. As such, it represents an interesting therapeutic target to tackle HIV infection. In this study, we screened hundreds of compounds with a low cost of synthesis for their ability to interfere with Gag assembly in vitro. Representatives of the most promising families of compounds were then tested for their ability to inhibit HIV-1 replication in cellulo. From these molecules, a hit compound from the benzimidazole family with high metabolic stability and low toxicity, 2-(4-N,N-dimethylaminophenyl)-5-methyl-1-phenethyl-1H-benzimidazole (696), appeared to block HIV-1 replication with an IC50 of 3 µM. Quantitative PCR experiments demonstrated that 696 does not block HIV-1 infection before the end of reverse transcription, and molecular docking confirmed that 696 is likely to bind at the interface between two monomers of CA and interfere with capsid oligomerization. Altogether, 696 represents a promising lead molecule for the development of a new series of HIV-1 inhibitors.
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7
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Nishiyama T, Takada T, Takeuchi H, Iwami S. Maternal embryonic leucine zipper kinase (MELK) optimally regulates the HIV-1 uncoating process. J Theor Biol 2022; 545:111152. [DOI: 10.1016/j.jtbi.2022.111152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 04/13/2022] [Accepted: 04/29/2022] [Indexed: 11/25/2022]
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8
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Winans S, Yu HJ, de Los Santos K, Wang GZ, KewalRamani VN, Goff SP. A point mutation in HIV-1 integrase redirects proviral integration into centromeric repeats. Nat Commun 2022; 13:1474. [PMID: 35304442 PMCID: PMC8933506 DOI: 10.1038/s41467-022-29097-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 02/24/2022] [Indexed: 11/25/2022] Open
Abstract
Retroviruses utilize the viral integrase (IN) protein to integrate a DNA copy of their genome into host chromosomal DNA. HIV-1 integration sites are highly biased towards actively transcribed genes, likely mediated by binding of the IN protein to specific host factors, particularly LEDGF, located at these gene regions. We here report a substantial redirection of integration site distribution induced by a single point mutation in HIV-1 IN. Viruses carrying the K258R IN mutation exhibit a high frequency of integrations into centromeric alpha satellite repeat sequences, as assessed by deep sequencing, a more than 10-fold increase over wild-type. Quantitative PCR and in situ immunofluorescence assays confirm this bias of the K258R mutant virus for integration into centromeric DNA. Immunoprecipitation studies identify host factors binding to IN that may account for the observed bias for integration into centromeres. Centromeric integration events are known to be enriched in the latent reservoir of infected memory T cells, as well as in elite controllers who limit viral replication without intervention. The K258R point mutation in HIV-1 IN is also present in databases of latent proviruses found in patients, and may reflect an unappreciated aspect of the establishment of viral latency. HIV-1 integration sites are biased towards actively transcribed genes, likely mediated by binding of the viral integrase (IN) protein to host factors. Here, Winans et al. show that the K258R point mutation in IN eredirects viral DNA integration to the centromeres of host chromosomes, which may affect HIV latency.
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Affiliation(s)
- Shelby Winans
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, NY, USA.,Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA.,Howard Hughes Medical Institute, Columbia University, New York, NY, USA
| | - Hyun Jae Yu
- Basic Science Program, Leidos Biomedical Research, Frederick National Laboratory, Frederick, MD, USA
| | - Kenia de Los Santos
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, NY, USA.,Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA.,Howard Hughes Medical Institute, Columbia University, New York, NY, USA
| | - Gary Z Wang
- Department of Pathology, Columbia University Medical Center, New York, NY, USA
| | - Vineet N KewalRamani
- Basic Research Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Stephen P Goff
- Department of Biochemistry and Molecular Biophysics, Columbia University Medical Center, New York, NY, USA. .,Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA. .,Howard Hughes Medical Institute, Columbia University, New York, NY, USA.
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9
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Gruenke PR, Aneja R, Welbourn S, Ukah OB, Sarafianos SG, Burke DH, Lange MJ. Selection and identification of an RNA aptamer that specifically binds the HIV-1 capsid lattice and inhibits viral replication. Nucleic Acids Res 2022; 50:1701-1717. [PMID: 35018437 PMCID: PMC8860611 DOI: 10.1093/nar/gkab1293] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/23/2021] [Accepted: 12/16/2021] [Indexed: 01/25/2023] Open
Abstract
The HIV-1 capsid core participates in several replication processes. The mature capsid core is a lattice composed of capsid (CA) monomers thought to assemble first into CA dimers, then into ∼250 CA hexamers and 12 CA pentamers. CA assembly requires conformational flexibility of each unit, resulting in the presence of unique, solvent-accessible surfaces. Significant advances have improved our understanding of the roles of the capsid core in replication; however, the contributions of individual CA assembly forms remain unclear and there are limited tools available to evaluate these forms in vivo. Here, we have selected aptamers that bind CA lattice tubes. We describe aptamer CA15-2, which selectively binds CA lattice, but not CA monomer or CA hexamer, suggesting that it targets an interface present and accessible only on CA lattice. CA15-2 does not compete with PF74 for binding, indicating that it likely binds a non-overlapping site. Furthermore, CA15-2 inhibits HIV-1 replication when expressed in virus producer cells, but not target cells, suggesting that it binds a biologically-relevant site during virus production that is either not accessible during post-entry replication steps or is accessible but unaltered by aptamer binding. Importantly, CA15-2 represents the first aptamer that specifically recognizes the HIV-1 CA lattice.
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Affiliation(s)
- Paige R Gruenke
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Rachna Aneja
- Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Sarah Welbourn
- Emory Vaccine Center and Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
| | - Obiaara B Ukah
- Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Donald H Burke
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA.,Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA.,Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
| | - Margaret J Lange
- Department of Molecular Microbiology & Immunology, School of Medicine, University of Missouri, Columbia, MO 65211, USA
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10
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Sahani RL, Akther T, Cilento ME, Castaner AE, Zhang H, Kirby KA, Xie J, Sarafianos SG, Wang Z. Potency and metabolic stability: a molecular hybrid case in the design of novel PF74-like small molecules targeting HIV-1 capsid protein. RSC Med Chem 2021; 12:2031-2044. [PMID: 35028563 DOI: 10.1039/d1md00292a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/27/2021] [Indexed: 12/27/2022] Open
Abstract
PF74 (1) is a potent and well-characterized prototypical small molecule targeting human immunodeficiency virus type 1 (HIV-1) capsid protein (CA), but not a viable antiviral lead due to the lack of metabolic stability. We report herein our molecular hybridization-based medicinal chemistry efforts toward potent and metabolically stable PF74-like small molecules. The design of the new sub-chemotype 4 rationally combines binding features of two recently reported PF74-like compounds 2 and 3. The subsequent confirmation and structure-activity relationship (SAR) of hit 4a entailed the chemical synthesis of 37 novel analogs, most of which showed modest but meaningful thermal shift, and low μM antiviral activity. The most potent analogs (4a, 4d, 4o, and 4r) all exhibited noticeably improved metabolic stability over PF74. Molecular modeling suggests that these new analogs bind to the PF74 binding site. Overall, our work demonstrated that the molecular hybridization approach is suitable for designing compounds with balanced potency and metabolic stability.
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Affiliation(s)
- Rajkumar Lalji Sahani
- Center for Drug Design, College of Pharmacy, University of Minnesota Minneapolis MN 55455 USA
| | - Thamina Akther
- Center for Drug Design, College of Pharmacy, University of Minnesota Minneapolis MN 55455 USA
| | - Maria E Cilento
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine Atlanta GA 30322 USA
| | - Andres Emanuelli Castaner
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine Atlanta GA 30322 USA
| | - Huanchun Zhang
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine Atlanta GA 30322 USA
| | - Karen A Kirby
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine Atlanta GA 30322 USA.,Children's Healthcare of Atlanta Atlanta GA 30322 USA
| | - Jiashu Xie
- Center for Drug Design, College of Pharmacy, University of Minnesota Minneapolis MN 55455 USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine Atlanta GA 30322 USA.,Children's Healthcare of Atlanta Atlanta GA 30322 USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota Minneapolis MN 55455 USA
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11
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Saito A, Yamashita M. HIV-1 capsid variability: viral exploitation and evasion of capsid-binding molecules. Retrovirology 2021; 18:32. [PMID: 34702294 PMCID: PMC8549334 DOI: 10.1186/s12977-021-00577-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/13/2021] [Indexed: 11/17/2022] Open
Abstract
The HIV-1 capsid, a conical shell encasing viral nucleoprotein complexes, is involved in multiple post-entry processes during viral replication. Many host factors can directly bind to the HIV-1 capsid protein (CA) and either promote or prevent HIV-1 infection. The viral capsid is currently being explored as a novel target for therapeutic interventions. In the past few decades, significant progress has been made in our understanding of the capsid–host interactions and mechanisms of action of capsid-targeting antivirals. At the same time, a large number of different viral capsids, which derive from many HIV-1 mutants, naturally occurring variants, or diverse lentiviruses, have been characterized for their interactions with capsid-binding molecules in great detail utilizing various experimental techniques. This review provides an overview of how sequence variation in CA influences phenotypic properties of HIV-1. We will focus on sequence differences that alter capsid–host interactions and give a brief account of drug resistant mutations in CA and their mutational effects on viral phenotypes. Increased knowledge of the sequence-function relationship of CA helps us deepen our understanding of the adaptive potential of the viral capsid.
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Affiliation(s)
- Akatsuki Saito
- Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, Miyazaki, Miyazaki, Japan.,Center for Animal Disease Control, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Masahiro Yamashita
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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12
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Davids BO, Balasubramaniam M, Sapp N, Prakash P, Ingram S, Li M, Craigie R, Hollis T, Pandhare J, Dash C. Human Three Prime Repair Exonuclease 1 Promotes HIV-1 Integration by Preferentially Degrading Unprocessed Viral DNA. J Virol 2021; 95:e0055521. [PMID: 34105995 PMCID: PMC8354242 DOI: 10.1128/jvi.00555-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/25/2021] [Indexed: 11/20/2022] Open
Abstract
Three prime repair exonuclease 1 (TREX1) is the most abundant 3'→5' exonuclease in mammalian cells. It has been suggested that TREX1 degrades HIV-1 DNA to enable the virus to evade the innate immune system. However, the exact role of TREX1 during early steps of HIV-1 infection is not clearly understood. In this study, we report that HIV-1 infection is associated with upregulation, perinuclear accumulation, and nuclear localization of TREX1. However, TREX1 overexpression did not affect reverse transcription or nuclear entry of the virus. Surprisingly, HIV-1 DNA integration was increased in TREX1-overexpressing cells, suggesting a role of the exonuclease in the post-nuclear entry step of infection. Accordingly, preintegration complexes (PICs) extracted from TREX1-overexpressing cells retained higher levels of DNA integration activity. TREX1 depletion resulted in reduced levels of proviral integration, and PICs formed in TREX1-depleted cells retained lower DNA integration activity. Addition of purified TREX1 to PICs also enhanced DNA integration activity, suggesting that TREX1 promotes HIV-1 integration by stimulating PIC activity. To understand the mechanism, we measured TREX1 exonuclease activity on substrates containing viral DNA ends. These studies revealed that TREX1 preferentially degrades the unprocessed viral DNA, but the integration-competent 3'-processed viral DNA remains resistant to degradation. Finally, we observed that TREX1 addition stimulates the activity of HIV-1 intasomes assembled with the unprocessed viral DNA but not that of intasomes containing the 3'-processed viral DNA. These biochemical analyses provide a mechanism by which TREX1 directly promotes HIV-1 integration. Collectively, our study demonstrates that HIV-1 infection upregulates TREX1 to facilitate viral DNA integration. IMPORTANCE Productive HIV-1 infection is dependent on a number of cellular factors. Therefore, a clear understanding of how the virus exploits the cellular machinery will identify new targets for inhibiting HIV-1 infection. The three prime repair exonuclease 1 (TREX1) is the most active cellular exonuclease in mammalian cells. It has been reported that TREX1 prevents accumulation of HIV-1 DNA and enables the virus to evade the host innate immune response. Here, we show that HIV-1 infection results in the upregulation, perinuclear accumulation, and nuclear localization of TREX1. We also provide evidence that TREX1 promotes HIV-1 integration by preferentially degrading viral DNAs that are incompatible with chromosomal insertion. These observations identify a novel role of TREX1 in a post-nuclear entry step of HIV-1 infection.
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Affiliation(s)
- Benem-Orom Davids
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Muthukumar Balasubramaniam
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Nicklas Sapp
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Prem Prakash
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Shalonda Ingram
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
| | - Min Li
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Robert Craigie
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Thomas Hollis
- Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Jui Pandhare
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Microbiology, Immunology, and Physiology, Meharry Medical College, Nashville, Tennessee, USA
- School of Graduate Studies and Research, Meharry Medical College, Nashville, Tennessee, USA
| | - Chandravanu Dash
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, Tennessee, USA
- Department of Biochemistry, Cancer Biology, Pharmacology and Neuroscience, Meharry Medical College, Nashville, Tennessee, USA
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13
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AlBurtamani N, Paul A, Fassati A. The Role of Capsid in the Early Steps of HIV-1 Infection: New Insights into the Core of the Matter. Viruses 2021; 13:v13061161. [PMID: 34204384 PMCID: PMC8234406 DOI: 10.3390/v13061161] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/10/2021] [Accepted: 06/14/2021] [Indexed: 01/27/2023] Open
Abstract
In recent years, major advances in research and experimental approaches have significantly increased our knowledge on the role of the HIV-1 capsid in the virus life cycle, from reverse transcription to integration and gene expression. This makes the capsid protein a good pharmacological target to inhibit HIV-1 replication. This review covers our current understanding of the role of the viral capsid in the HIV-1 life cycle and its interaction with different host factors that enable reverse transcription, trafficking towards the nucleus, nuclear import and integration into host chromosomes. It also describes different promising small molecules, some of them in clinical trials, as potential targets for HIV-1 therapy.
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14
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Novel PF74-like small molecules targeting the HIV-1 capsid protein: Balance of potency and metabolic stability. Acta Pharm Sin B 2021; 11:810-822. [PMID: 33777683 PMCID: PMC7982424 DOI: 10.1016/j.apsb.2020.07.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/08/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022] Open
Abstract
Of all known small molecules targeting human immunodeficiency virus (HIV) capsid protein (CA), PF74 represents by far the best characterized chemotype, due to its ability to confer antiviral phenotypes in both early and late phases of viral replication. However, the prohibitively low metabolic stability renders PF74 a poor antiviral lead. We report herein our medicinal chemistry efforts toward identifying novel and metabolically stable small molecules targeting the PF74 binding site. Specifically, we replaced the inter-domain-interacting, electron-rich indole ring of PF74 with less electron-rich isosteres, including imidazolidine-2,4-dione, pyrimidine-2,4-dione, and benzamide, and identified four potent antiviral compounds (10, 19, 20 and 26) with markedly improved metabolic stability. Compared to PF74, analog 20 exhibited similar submicromolar potency, and much longer (51-fold) half-life in human liver microsomes (HLMs). Molecular docking corroborated that 20 binds to the PF74 binding site, and revealed distinct binding interactions conferred by the benzamide moiety. Collectively, our data support compound 20 as a promising antiviral lead.
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Key Words
- ART, antiretroviral therapy
- CA, capsid protein
- CACTD, CA C-terminal domain
- CANTD, CA N-terminal domain
- Capsid protein
- HBA, H-bond acceptor
- HBD, H-bond donor
- HIV, human immunodeficiency virus
- HIV-1
- HLM, human liver microsome
- MLM, mouse liver microsome
- Microsomal stability
- PF74
- PK, pharmacokinetic
- SAR, structure‒activity relationship
- TSA, thermal shift assay
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15
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Scoca V, Di Nunzio F. The HIV-1 Capsid: From Structural Component to Key Factor for Host Nuclear Invasion. Viruses 2021; 13:273. [PMID: 33578999 PMCID: PMC7916756 DOI: 10.3390/v13020273] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/29/2021] [Accepted: 02/05/2021] [Indexed: 02/07/2023] Open
Abstract
Since the discovery of HIV-1, the viral capsid has been recognized to have an important role as a structural protein that holds the viral genome, together with viral proteins essential for viral life cycle, such as the reverse transcriptase (RT) and the integrase (IN). The reverse transcription process takes place between the cytoplasm and the nucleus of the host cell, thus the Reverse Transcription Complexes (RTCs)/Pre-integration Complexes (PICs) are hosted in intact or partial cores. Early biochemical assays failed to identify the viral CA associated to the RTC/PIC, possibly due to the stringent detergent conditions used to fractionate the cells or to isolate the viral complexes. More recently, it has been observed that some host partners of capsid, such as Nup153 and CPSF6, can only bind multimeric CA proteins organized in hexamers. Those host factors are mainly located in the nuclear compartment, suggesting the entrance of the viral CA as multimeric structure inside the nucleus. Recent data show CA complexes within the nucleus having a different morphology from the cytoplasmic ones, clearly highlighting the remodeling of the viral cores during nuclear translocation. Thus, the multimeric CA complexes lead the viral genome into the host nuclear compartment, piloting the intranuclear journey of HIV-1 in order to successfully replicate. The aim of this review is to discuss and analyze the main discoveries to date that uncover the viral capsid as a key player in the reverse transcription and PIC maturation until the viral DNA integration into the host genome.
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Affiliation(s)
- Viviana Scoca
- Advanced Molecular Virology and Retroviral Dynamics Group, Department of Virology Pasteur Institute, 75015 Paris, France;
- BioSPC Doctoral School, Universitè de Paris, 75015 Paris, France
| | - Francesca Di Nunzio
- Advanced Molecular Virology and Retroviral Dynamics Group, Department of Virology Pasteur Institute, 75015 Paris, France;
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16
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Li J, Mo C, Guo Y, Zhang B, Feng X, Si Q, Wu X, Zhao Z, Gong L, He D, Shao J. Roles of peptidyl-prolyl isomerase Pin1 in disease pathogenesis. Theranostics 2021; 11:3348-3358. [PMID: 33537091 PMCID: PMC7847688 DOI: 10.7150/thno.45889] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 12/02/2020] [Indexed: 12/21/2022] Open
Abstract
Pin1 belongs to the peptidyl-prolyl cis-trans isomerases (PPIases) superfamily and catalyzes the cis-trans conversion of proline in target substrates to modulate diverse cellular functions including cell cycle progression, cell motility, and apoptosis. Dysregulation of Pin1 has wide-ranging influences on the fate of cells; therefore, it is closely related to the occurrence and development of various diseases. This review summarizes the current knowledge of Pin1 in disease pathogenesis.
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17
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Wang L, Casey MC, Vernekar SKV, Sahani RL, Kankanala J, Kirby KA, Du H, Hachiya A, Zhang H, Tedbury PR, Xie J, Sarafianos SG, Wang Z. Novel HIV-1 capsid-targeting small molecules of the PF74 binding site. Eur J Med Chem 2020; 204:112626. [PMID: 32814250 DOI: 10.1016/j.ejmech.2020.112626] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/22/2020] [Accepted: 06/25/2020] [Indexed: 10/23/2022]
Abstract
The PF74 binding site in HIV-1 capsid protein (CA) is a compelling antiviral drug target. Although PF74 confers mechanistically distinct antiviral phenotypes by competing against host factors for CA binding, it suffers from prohibitively low metabolic stability. Therefore, there has been increasing interest in designing novel sub-chemotypes of PF74 with similar binding mode and improved metabolic stability. We report herein our efforts to explore the inter-domain interacting indole moiety for designing novel CA-targeting small molecules. Our design includes simple substitution on the indole ring, and more importantly, novel sub-chemotypes with the indole moiety replaced with a few less electron-rich rings. All 56 novel analogs were synthesized and evaluated for antiviral activity, cytotoxicity, and impact on CA hexamer stability. Selected analogs were tested for metabolic stability in liver microsomes. Molecular modeling was performed to verify compound binding to the PF74 site. In the end, 5-hydroxyindole analogs (8,9 and 12) showed improved potency (up to 20-fold) over PF74. Of the novel sub-chemotypes, α- and β-naphthyl analogs (33 and 27) exhibited sub micromolar antiviral potencies comparable to that of PF74. Interestingly, although only moderately inhibiting HIV-1 (single-digit micromolar EC50s), analogs of the 2-indolone sub-chemotype consistently lowered the melting point (Tm) of CA hexamers, some with improved metabolic stability over PF74.
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Affiliation(s)
- Lei Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Mary C Casey
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Christopher S. Bond Life Sciences Center, Columbia, MO, 65211, USA
| | - Sanjeev Kumar V Vernekar
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Rajkumar Lalji Sahani
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Jayakanth Kankanala
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Karen A Kirby
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Haijuan Du
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Atsuko Hachiya
- Clinical Research Center, Nagoya Medical Center, National Hospital Organization, Nagoya, Aichi, 460-0001, Japan
| | - Huanchun Zhang
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Philip R Tedbury
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Jiashu Xie
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA.
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18
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Maillet S, Fernandez J, Decourcelle M, El Koulali K, Blanchet FP, Arhel NJ, Maarifi G, Nisole S. Daxx Inhibits HIV-1 Reverse Transcription and Uncoating in a SUMO-Dependent Manner. Viruses 2020; 12:v12060636. [PMID: 32545337 PMCID: PMC7354551 DOI: 10.3390/v12060636] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/05/2020] [Accepted: 06/09/2020] [Indexed: 02/07/2023] Open
Abstract
Death domain-associated protein 6 (Daxx) is a multifunctional, ubiquitously expressed and highly conserved chaperone protein involved in numerous cellular processes, including apoptosis, transcriptional repression, and carcinogenesis. In 2015, we identified Daxx as an antiretroviral factor that interfered with HIV-1 replication by inhibiting the reverse transcription step. In the present study, we sought to unravel the molecular mechanism of Daxx-mediated restriction and, in particular, to identify the protein(s) that Daxx targets in order to achieve its antiviral activity. First, we show that the SUMO-interacting motif (SIM) located at the C-terminus of the protein is strictly required for Daxx to inhibit HIV-1 reverse transcription. By performing a quantitative proteomic screen combined with classical biochemical analyses, we found that Daxx associated with incoming HIV-1 cores through a SIM-dependent interaction with cyclophilin A (CypA) and capsid (CA). Daxx was found to reside within a multiprotein complex associated with viral capsids, also containing TNPO3, TRIM5α, and TRIM34. Given the well-known influence of these cellular factors on the stability of HIV-1 cores, we investigated the effect of Daxx on the cytoplasmic fate of incoming cores and found that Daxx prevented HIV-1 uncoating in a SIM-dependent manner. Altogether, our findings suggest that, by recruiting TNPO3, TRIM5α, and TRIM34 and possibly other proteins onto incoming HIV-1 cores through a SIM-dependent interaction with CA-bound CypA, Daxx increases their stability, thus preventing uncoating and reverse transcription. Our study uncovers a previously unknown function of Daxx in the early steps of HIV-1 infection and further illustrates how reverse transcription and uncoating are two tightly interdependent processes.
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Affiliation(s)
- Sarah Maillet
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
| | - Juliette Fernandez
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
| | - Mathilde Decourcelle
- BCM, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (M.D.); (K.E.K.)
| | - Khadija El Koulali
- BCM, Université de Montpellier, CNRS, INSERM, 34090 Montpellier, France; (M.D.); (K.E.K.)
| | - Fabien P. Blanchet
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
| | - Nathalie J. Arhel
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
| | - Ghizlane Maarifi
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
| | - Sébastien Nisole
- Institut de Recherche en Infectiologie de Montpellier (IRIM), Université de Montpellier, CNRS, 34090 Montpellier, France; (S.M.); (J.F.); (F.P.B.); (N.J.A.); (G.M.)
- Correspondence:
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19
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Cevik M, Orkin C. Insights into HIV-1 capsid inhibitors in preclinical and early clinical development as antiretroviral agents. Expert Opin Investig Drugs 2019; 28:1021-1024. [PMID: 31738620 DOI: 10.1080/13543784.2019.1692811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Muge Cevik
- Infection and Global Health Research, School of Medicine, University of St Andrews, St Andrews, UK
| | - Chloe Orkin
- Blizard Institute, Queen Mary University of London, London, UK.,Royal London Hospital,Ambrose King Centre, Barts Health NHS Trust, London, UK
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20
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Maeda K, Das D, Kobayakawa T, Tamamura H, Takeuchi H. Discovery and Development of Anti-HIV Therapeutic Agents: Progress Towards Improved HIV Medication. Curr Top Med Chem 2019; 19:1621-1649. [PMID: 31424371 PMCID: PMC7132033 DOI: 10.2174/1568026619666190712204603] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/14/2019] [Accepted: 06/21/2019] [Indexed: 01/09/2023]
Abstract
The history of the human immunodeficiency virus (HIV)/AIDS therapy, which spans over 30 years, is one of the most dramatic stories of science and medicine leading to the treatment of a disease. Since the advent of the first AIDS drug, AZT or zidovudine, a number of agents acting on different drug targets, such as HIV enzymes (e.g. reverse transcriptase, protease, and integrase) and host cell factors critical for HIV infection (e.g. CD4 and CCR5), have been added to our armamentarium to combat HIV/AIDS. In this review article, we first discuss the history of the development of anti-HIV drugs, during which several problems such as drug-induced side effects and the emergence of drug-resistant viruses became apparent and had to be overcome. Nowadays, the success of Combination Antiretroviral Therapy (cART), combined with recently-developed powerful but nonetheless less toxic drugs has transformed HIV/AIDS from an inevitably fatal disease into a manageable chronic infection. However, even with such potent cART, it is impossible to eradicate HIV because none of the currently available HIV drugs are effective in eliminating occult “dormant” HIV cell reservoirs. A number of novel unique treatment approaches that should drastically improve the quality of life (QOL) of patients or might actually be able to eliminate HIV altogether have also been discussed later in the review.
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Affiliation(s)
- Kenji Maeda
- National Center for Global Health and Medicine (NCGM) Research Institute, Tokyo 162-8655, Japan
| | - Debananda Das
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health (NCI/NIH), Bethesda, MD, United States
| | - Takuya Kobayakawa
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo 101-0062, Japan
| | - Hirokazu Tamamura
- Department of Molecular Virology, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
| | - Hiroaki Takeuchi
- Department of Molecular Virology, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
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21
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Dominant Negative MA-CA Fusion Protein Is Incorporated into HIV-1 Cores and Inhibits Nuclear Entry of Viral Preintegration Complexes. J Virol 2019; 93:JVI.01118-19. [PMID: 31413124 DOI: 10.1128/jvi.01118-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 08/03/2019] [Indexed: 11/20/2022] Open
Abstract
Particle maturation is a critical step in the HIV-1 replication cycle that requires proteolytic cleavage of the Gag polyprotein into its constitutive proteins: the matrix (MA), capsid (CA), nucleocapsid (NC), and p6 proteins. The accurate and efficient cleavage of Gag is essential for virion infectivity; inhibitors of the viral protease are potent antivirals, and substitutions in Gag that prevent its cleavage result in reduced HIV-1 infectivity. In a previous study, a mutation inhibiting cleavage at the MA-CA junction was observed to potently inhibit virus infection: incorporation of small amounts of uncleaved MA-CA protein into HIV-1 particles inhibited infectivity by ∼95%, and the resulting viral particles exhibited aberrant capsids. Here we report a detailed mechanistic analysis of HIV-1 particles bearing uncleaved MA-CA protein. We show that the particles contain stable cores and can efficiently saturate host restriction by TRIMCyp in target cells. We further show that MA-CA associates with CA in particles without detectably affecting the formation of intermolecular CA interfaces. Incorporation of MA-CA did not markedly affect reverse transcription in infected cells, but nuclear entry was impaired and integration targeting was altered. Additionally, results from mutational analysis of Gag revealed that membrane-binding elements of MA contribute to the antiviral activity of uncleaved MA-CA protein. Our results suggest that small amounts of partially processed Gag subunits coassemble with CA during virion maturation, resulting in impaired capsid functions.IMPORTANCE To become infectious, newly formed HIV-1 particles undergo a process of maturation in which the viral polyproteins are cleaved into smaller components. A previous study demonstrated that inclusion of even small quantities of an uncleavable mutant Gag polyprotein results in a strong reduction in virus infectivity. Here we show that the mechanism of transdominant inhibition by uncleavable Gag involves inhibition of nuclear entry and alteration of viral integration sites. Additionally, the results of mutational analysis suggest that the membrane-binding activity of Gag is a major requirement for the antiviral activity. These results further define the antiviral mechanism of uncleavable Gag, which may be useful for exploiting this effect to develop new antivirals.
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22
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The Conserved Tyr176/Leu177 Motif in the α-Helix 9 of the Feline Immunodeficiency Virus Capsid Protein Is Critical for Gag Particle Assembly. Viruses 2019; 11:v11090816. [PMID: 31487820 PMCID: PMC6783973 DOI: 10.3390/v11090816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/31/2019] [Accepted: 09/02/2019] [Indexed: 01/19/2023] Open
Abstract
The capsid domain (CA) of the lentiviral Gag polyproteins has two distinct roles during virion morphogenesis. As a domain of Gag, it mediates the Gag–Gag interactions that drive immature particle assembly, whereas as a mature protein, it self-assembles into the conical core of the mature virion. Lentiviral CA proteins are composed of an N-terminal region with seven α-helices and a C-terminal domain (CA-CTD) formed by four α-helices. Structural studies performed in HIV-1 indicate that the CA-CTD helix 9 establishes homodimeric interactions that contribute to the formation of the hexameric Gag lattice in immature virions. Interestingly, the mature CA core also shows inter-hexameric associations involving helix 9 residues W184 and M185. The CA proteins of feline immunodeficiency virus (FIV) and equine infectious anemia virus (EIAV) exhibit, at equivalent positions in helix 9, the motifs Y176/L177 and L169/F170, respectively. In this paper, we investigated the relevance of the Y176/L177 motif for FIV assembly by introducing a series of amino acid substitutions into this sequence and studying their effect on in vivo and in vitro Gag assembly, CA oligomerization, mature virion production, and viral infectivity. Our results demonstrate that the Y176/L177 motif in FIV CA helix 9 is essential for Gag assembly and CA oligomerization. Notably, mutations converting the FIV CA Y176/L177 motif into the HIV-1 WM and EIAV FL sequences allow substantial particle production and viral replication in feline cells.
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23
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A Novel Phenotype Links HIV-1 Capsid Stability to cGAS-Mediated DNA Sensing. J Virol 2019; 93:JVI.00706-19. [PMID: 31167922 DOI: 10.1128/jvi.00706-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 05/19/2019] [Indexed: 01/27/2023] Open
Abstract
The HIV-1 capsid executes essential functions that are regulated by capsid stability and host factors. In contrast to increasing knowledge on functional roles of capsid-interacting host proteins during postentry steps, less is known about capsid stability and its impact on intracellular events. Here, using the antiviral compound PF-3450074 (PF74) as a probe for capsid function, we uncovered a novel phenotype of capsid stability that has a profound effect on innate sensing of viral DNA by the DNA sensor cGAS. A single mutation, R143A, in the capsid protein conferred resistance to high concentrations of PF74, without affecting capsid binding to PF74. A cell-free assay showed that the R143A mutant partially counteracted the capsid-destabilizing activity of PF74, pointing to capsid stabilization as a resistance mechanism for the R143A mutant. In monocytic THP-1 cells, the R143A virus, but not the wild-type virus, suppressed cGAS-dependent innate immune activation. These results suggest that capsid stabilization improves the shielding of viral DNA from innate sensing. We found that a naturally occurring transmitted founder (T/F) variant shares the same properties as the R143A mutant with respect to PF74 resistance and DNA sensing. Imaging assays revealed delayed uncoating kinetics of this T/F variant and the R143A mutant. All these phenotypes of this T/F variant were controlled by a genetic polymorphism located at the trimeric interface between capsid hexamers, thus linking these capsid-dependent properties. Overall, this work functionally connects capsid stability to innate sensing of viral DNA and reveals naturally occurring phenotypic variation in HIV-1 capsid stability.IMPORTANCE The HIV-1 capsid, which is made from individual viral capsid proteins (CA), is a target for a number of antiviral compounds, including the small-molecule inhibitor PF74. In the present study, we utilized PF74 to identify a transmitted/founder (T/F) strain that shows increased capsid stability. Interestingly, PF74-resistant variants prevented cGAS-dependent innate immune activation under a condition where the other T/F strains induced type I interferon. These observations thus reveal a new CA-specific phenotype that couples capsid stability to viral DNA recognition by cytosolic DNA sensors.
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24
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Balasubramaniam M, Pandhare J, Dash C. Immune Control of HIV. JOURNAL OF LIFE SCIENCES (WESTLAKE VILLAGE, CALIF.) 2019; 1:4-37. [PMID: 31468033 PMCID: PMC6714987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The human immunodeficiency virus (HIV) infection of the immune cells expressing the cluster of differentiation 4 cell surface glycoprotein (CD4+ cells) causes progressive decline of the immune system and leads to the acquired immunodeficiency syndrome (AIDS). The ongoing global HIV/AIDS pandemic has already claimed over 35 million lives. Even after 37 years into the epidemic, neither a cure is available for the 37 million people living with HIV (PLHIV) nor is a vaccine discovered to avert the millions of new HIV infections that continue to occur each year. If left untreated, HIV infection typically progresses to AIDS and, ultimately, causes death in a majority of PLHIV. The recommended combination antiretroviral therapy (cART) suppresses virus replication and viremia, prevents or delays progression to AIDS, reduces transmission rates, and lowers HIV-associated mortality and morbidity. However, because cART does not eliminate HIV, and an enduring pool of infected resting memory CD4+ T cells (latent HIV reservoir) is established early on, any interruption to cART leads to a relapse of viremia and disease progression. Hence, strict adherence to a life-long cART regimen is mandatory for managing HIV infection in PLHIV. The HIV-1-specific cytotoxic T cells expressing the CD8 glycoprotein (CD8+ CTL) limit the virus replication in vivo by recognizing the viral antigens presented by human leukocyte antigen (HLA) class I molecules on the infected cell surface and killing those cells. Nevertheless, CTLs fail to durably control HIV-1 replication and disease progression in the absence of cART. Intriguingly, <1% of cART-naive HIV-infected individuals called elite controllers/HIV controllers (HCs) exhibit the core features that define a HIV-1 "functional cure" outcome in the absence of cART: durable viral suppression to below the limit of detection, long-term non-progression to AIDS, and absence of viral transmission. Robust HIV-1-specific CTL responses and prevalence of protective HLA alleles associated with enduring HIV-1 control have been linked to the HC phenotype. An understanding of the molecular mechanisms underlying the CTL-mediated suppression of HIV-1 replication and disease progression in HCs carrying specific protective HLA alleles may yield promising insights towards advancing the research on HIV cure and prophylactic HIV vaccine.
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Affiliation(s)
- Muthukumar Balasubramaniam
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, TN – 37208. USA
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN – 37208. USA
| | - Jui Pandhare
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, TN – 37208. USA
- School of Graduate Studies and Research, Meharry Medical College, Nashville, TN – 37208. USA
| | - Chandravanu Dash
- Center for AIDS Health Disparities Research, Meharry Medical College, Nashville, TN – 37208. USA
- Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN – 37208. USA
- School of Graduate Studies and Research, Meharry Medical College, Nashville, TN – 37208. USA
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25
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Novikova M, Zhang Y, Freed EO, Peng K. Multiple Roles of HIV-1 Capsid during the Virus Replication Cycle. Virol Sin 2019; 34:119-134. [PMID: 31028522 PMCID: PMC6513821 DOI: 10.1007/s12250-019-00095-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 01/16/2019] [Indexed: 11/29/2022] Open
Abstract
Human immunodeficiency virus-1 capsid (HIV-1 CA) is involved in different stages of the viral replication cycle. During virion assembly, CA drives the formation of the hexameric lattice in immature viral particles, while in mature virions CA monomers assemble in cone-shaped cores surrounding the viral RNA genome and associated proteins. In addition to its functions in late stages of the viral replication cycle, CA plays key roles in a number of processes during early phases of HIV-1 infection including trafficking, uncoating, recognition by host cellular proteins and nuclear import of the viral pre-integration complex. As a result of efficient cooperation of CA with other viral and cellular proteins, integration of the viral genetic material into the host genome, which is an essential step for productive viral infection, successfully occurs. In this review, we will summarize available data on CA functions in HIV-1 replication, describing in detail its roles in late and early phases of the viral replication cycle.
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Affiliation(s)
- Mariia Novikova
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, USA
| | - Yulan Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Eric O Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702, USA.
| | - Ke Peng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China.
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Balasubramaniam M, Zhou J, Addai A, Martinez P, Pandhare J, Aiken C, Dash C. PF74 Inhibits HIV-1 Integration by Altering the Composition of the Preintegration Complex. J Virol 2019; 93:e01741-18. [PMID: 30567984 PMCID: PMC6401427 DOI: 10.1128/jvi.01741-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 12/06/2018] [Indexed: 11/20/2022] Open
Abstract
The HIV-1 capsid protein (CA) facilitates reverse transcription and nuclear entry of the virus. However, CA's role in post-nuclear entry steps remains speculative. We describe a direct link between CA and integration by employing the capsid inhibitor PF74 as a probe coupled with the biochemical analysis of HIV-1 preintegration complexes (PICs) isolated from acutely infected cells. At a low micromolar concentration, PF74 potently inhibited HIV-1 infection without affecting reverse transcription. Surprisingly, PF74 markedly reduced proviral integration owing to inhibition of nuclear entry and/or integration. However, a 2-fold reduction in nuclear entry by PF74 did not quantitatively correlate with the level of antiviral activity. Titration of PF74 against the integrase inhibitor raltegravir showed an additive antiviral effect that is dependent on a block at the post-nuclear entry step. PF74's inhibitory effect was not due to the formation of defective viral DNA ends or a delay in integration, suggesting that the compound inhibits PIC-associated integration activity. Unexpectedly, PICs recovered from cells infected in the presence of PF74 exhibited elevated integration activity. PF74's effect on PIC activity is CA specific since the compound did not increase the integration activity of PICs of a PF74-resistant HIV-1 CA mutant. Sucrose gradient-based fractionation studies revealed that PICs assembled in the presence of PF74 contained lower levels of CA, suggesting a negative association between CA and PIC-associated integration activity. Finally, the addition of a CA-specific antibody or PF74 inhibited PIC-associated integration activity. Collectively, our results demonstrate that PF74's targeting of PIC-associated CA results in impaired HIV-1 integration.IMPORTANCE Antiretroviral therapy (ART) that uses various combinations of small molecule inhibitors has been highly effective in controlling HIV. However, the drugs used in the ART regimen are expensive, cause side effects, and face viral resistance. The HIV-1 CA plays critical roles in the virus life cycle and is an attractive therapeutic target. While currently there is no CA-based therapy, highly potent CA-specific inhibitors are being developed as a new class of antivirals. Efforts to develop a CA-targeted therapy can be aided through a clear understanding of the role of CA in HIV-1 infection. CA is well established to coordinate reverse transcription and nuclear entry of the virus. However, the role of CA in post-nuclear entry steps of HIV-1 infection is poorly understood. We show that a CA-specific drug PF74 inhibits HIV-1 integration revealing a novel role of this multifunctional viral protein in a post-nuclear entry step of HIV-1 infection.
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Affiliation(s)
- Muthukumar Balasubramaniam
- Center for AIDS Health Disparities Research, Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Jing Zhou
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Amma Addai
- Center for AIDS Health Disparities Research, Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Phillip Martinez
- Center for AIDS Health Disparities Research, Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Jui Pandhare
- Center for AIDS Health Disparities Research, Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
| | - Christopher Aiken
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Chandravanu Dash
- Center for AIDS Health Disparities Research, Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, Tennessee, USA
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Suárez H, Rocha-Perugini V, Álvarez S, Yáñez-Mó M. Tetraspanins, Another Piece in the HIV-1 Replication Puzzle. Front Immunol 2018; 9:1811. [PMID: 30127789 PMCID: PMC6088189 DOI: 10.3389/fimmu.2018.01811] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 07/23/2018] [Indexed: 12/12/2022] Open
Abstract
Despite the great research effort placed during the last decades in HIV-1 study, still some aspects of its replication cycle remain unknown. All this powerful research has succeeded in developing different drugs for AIDS treatment, but none of them can completely remove the virus from infected patients, who require life-long medication. The classical approach was focused on the study of virus particles as the main target, but increasing evidence highlights the importance of host cell proteins in HIV-1 cycle. In this context, tetraspanins have emerged as critical players in different steps of the viral infection cycle. Through their association with other molecules, including membrane receptors, cytoskeletal proteins, and signaling molecules, tetraspanins organize specialized membrane microdomains called tetraspanin-enriched microdomains (TEMs). Within these microdomains, several tetraspanins have been described to regulate HIV-1 entry, assembly, and transfer between cells. Interestingly, the importance of tetraspanins CD81 and CD63 in the early steps of viral replication has been recently pointed out. Indeed, CD81 can control the turnover of the HIV-1 restriction factor SAMHD1. This deoxynucleoside triphosphate triphosphohydrolase counteracts HIV-1 reverse transcription (RT) in resting cells via its dual function as dNTPase, catalyzing deoxynucleotide triphosphates into deoxynucleosides and inorganic triphosphate, and as exonuclease able to degrade single-stranded RNAs. SAMHD1 has also been related with the detection of viral nucleic acids, regulating the innate immune response and would promote viral latency. New evidences demonstrating the ability of CD81 to control SAMHD1 expression, and as a consequence, HIV-1 RT activity, highlight the importance of TEMs for viral replication. Here, we will briefly review how tetraspanins modulate HIV-1 infection, focusing on the latest findings that link TEMs to viral replication.
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Affiliation(s)
- Henar Suárez
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain
| | - Vera Rocha-Perugini
- Servicio de Inmunología, Hospital de la Princesa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Madrid, Spain.,Vascular Pathophysiology Research Area, Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
| | - Susana Álvarez
- Servicio de Inmunobiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - María Yáñez-Mó
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Madrid, Spain.,Centro de Biología Molecular Severo Ochoa, Instituto de Investigación Sanitaria La Princesa (IIS-IP), Madrid, Spain
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Łopata K, Wojdas E, Nowak R, Łopata P, Mazurek U. Porcine Endogenous Retrovirus (PERV) - Molecular Structure and Replication Strategy in the Context of Retroviral Infection Risk of Human Cells. Front Microbiol 2018; 9:730. [PMID: 29755422 PMCID: PMC5932395 DOI: 10.3389/fmicb.2018.00730] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 03/28/2018] [Indexed: 12/28/2022] Open
Abstract
The xenotransplantation of porcine tissues may help overcome the shortage of human organs for transplantation. However, there are some concerns about recipient safety because the risk of porcine endogenous retrovirus (PERV) transmission to human cells remains unknown. Although, to date, no PERV infections have been noted in vivo, the possibility of such infections has been confirmed in vitro. Better understanding of the structure and replication cycle of PERVs is a prerequisite for determining the risk of infection and planning PERV-detection strategies. This review presents the current state of knowledge about the structure and replication cycle of PERVs in the context of retroviral infection risk.
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Affiliation(s)
- Krzysztof Łopata
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Emilia Wojdas
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland.,Department of Instrumental Analysis, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Roman Nowak
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Paweł Łopata
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
| | - Urszula Mazurek
- Department of Molecular Biology, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia, Katowice, Poland
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Are microRNAs Important Players in HIV-1 Infection? An Update. Viruses 2018; 10:v10030110. [PMID: 29510515 PMCID: PMC5869503 DOI: 10.3390/v10030110] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Revised: 02/21/2018] [Accepted: 02/25/2018] [Indexed: 12/15/2022] Open
Abstract
HIV-1 has already claimed over 35 million human lives globally. No curative treatments are currently available, and the only treatment option for over 36 million people currently living with HIV/AIDS are antiretroviral drugs that disrupt the function of virus-encoded proteins. However, such virus-targeted therapeutic strategies are constrained by the ability of the virus to develop drug-resistance. Despite major advances in HIV/AIDS research over the years, substantial knowledge gaps exist in many aspects of HIV-1 replication, especially its interaction with the host. Hence, understanding the mechanistic details of virus–host interactions may lead to novel therapeutic strategies for the prevention and/or management of HIV/AIDS. Notably, unprecedented progress in deciphering host gene silencing processes mediated by several classes of cellular small non-coding RNAs (sncRNA) presents a promising and timely opportunity for developing non-traditional antiviral therapeutic strategies. Cellular microRNAs (miRNA) belong to one such important class of sncRNAs that regulate protein synthesis. Evidence is mounting that cellular miRNAs play important roles in viral replication, either usurped by the virus to promote its replication or employed by the host to control viral infection by directly targeting the viral genome or by targeting cellular proteins required for productive virus replication. In this review, we summarize the findings to date on the role of miRNAs in HIV-1 biology.
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Che Nordin MA, Teow SY. Review of Current Cell-Penetrating Antibody Developments for HIV-1 Therapy. Molecules 2018; 23:molecules23020335. [PMID: 29415435 PMCID: PMC6017373 DOI: 10.3390/molecules23020335] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/06/2018] [Accepted: 01/08/2018] [Indexed: 12/22/2022] Open
Abstract
The discovery of highly active antiretroviral therapy (HAART) in 1996 has significantly reduced the global mortality and morbidity caused by the acquired immunodeficiency syndrome (AIDS). However, the therapeutic strategy of HAART that targets multiple viral proteins may render off-target toxicity and more importantly results in drug-resistant escape mutants. These have been the main challenges for HAART and refinement of this therapeutic strategy is urgently needed. Antibody-mediated treatments are emerging therapeutic modalities for various diseases. Most therapeutic antibodies have been approved by Food and Drug Administration (FDA) mainly for targeting cancers. Previous studies have also demonstrated the promising effect of therapeutic antibodies against HIV-1, but there are several limitations in this therapy, particularly when the viral targets are intracellular proteins. The conventional antibodies do not cross the cell membrane, hence, the pathogenic intracellular proteins cannot be targeted with this classical therapeutic approach. Over the years, the advancement of antibody engineering has permitted the therapeutic antibodies to comprehensively target both extra- and intra-cellular proteins in various infections and diseases. This review aims to update on the current progress in the development of antibody-based treatment against intracellular targets in HIV-1 infection. We also attempt to highlight the challenges and limitations in the development of antibody-based therapeutic modalities against HIV-1.
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Affiliation(s)
- Muhamad Alif Che Nordin
- Kulliyyah of Medicine and Health Sciences (KMHS), Kolej Universiti INSANIAH, 09300 Kuala Ketil, Kedah, Malaysia.
| | - Sin-Yeang Teow
- Sunway Institute for Healthcare Development (SIHD), School of Healthcare and Medical Sciences (SHMS), Sunway University, Jalan Universiti, Bandar Sunway, 47500 Subang Jaya, Selangor Darul Ehsan, Malaysia.
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Zhyvoloup A, Melamed A, Anderson I, Planas D, Lee CH, Kriston-Vizi J, Ketteler R, Merritt A, Routy JP, Ancuta P, Bangham CRM, Fassati A. Digoxin reveals a functional connection between HIV-1 integration preference and T-cell activation. PLoS Pathog 2017; 13:e1006460. [PMID: 28727807 PMCID: PMC5519191 DOI: 10.1371/journal.ppat.1006460] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/08/2017] [Indexed: 12/23/2022] Open
Abstract
HIV-1 integrates more frequently into transcribed genes, however the biological significance of HIV-1 integration targeting has remained elusive. Using a selective high-throughput chemical screen, we discovered that the cardiac glycoside digoxin inhibits wild-type HIV-1 infection more potently than HIV-1 bearing a single point mutation (N74D) in the capsid protein. We confirmed that digoxin repressed viral gene expression by targeting the cellular Na+/K+ ATPase, but this did not explain its selectivity. Parallel RNAseq and integration mapping in infected cells demonstrated that digoxin inhibited expression of genes involved in T-cell activation and cell metabolism. Analysis of >400,000 unique integration sites showed that WT virus integrated more frequently than N74D mutant within or near genes susceptible to repression by digoxin and involved in T-cell activation and cell metabolism. Two main gene networks down-regulated by the drug were CD40L and CD38. Blocking CD40L by neutralizing antibodies selectively inhibited WT virus infection, phenocopying digoxin. Thus the selectivity of digoxin depends on a combination of integration targeting and repression of specific gene networks. The drug unmasked a functional connection between HIV-1 integration and T-cell activation. Our results suggest that HIV-1 evolved integration site selection to couple its early gene expression with the status of target CD4+ T-cells, which may affect latency and viral reactivation. HIV-1 integrates more frequently within transcribed host genes, however we do not understand the biological significance of this. We found that a drug called digoxin inhibits wild type HIV-1 more potently than an HIV-1 bearing a single point mutation in the capsid protein. Here we show that digoxin represses HIV-1 gene expression and in parallel inhibits CD4+ T-cell activation and metabolism. When we analysed the integration sites of wild type and mutant HIV-1, we discovered that wild type virus integrates within or near genes involved in CD4+ T-cell activation and metabolism more often than the mutant virus. Because these are the very same genes repressed by digoxin, the integration bias of wild type virus makes it more susceptible than mutant virus to silencing by the drug. Digoxin unmasked a functional link between HIV-1 integration and T-cell activation, which may affect HIV-1 latency and reactivation.
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Affiliation(s)
- Alexander Zhyvoloup
- Division of Infection & Immunity, University College London, London, United Kingdom
| | - Anat Melamed
- Department of Medicine, Imperial College, St. Mary's Campus, London, United Kingdom
| | - Ian Anderson
- Division of Infection & Immunity, University College London, London, United Kingdom
| | - Delphine Planas
- Department of Microbiology, Infectiology and Immunology, Faculty of Medicine, University of Montreal and the Research Centre of the CHUM, Montreal, Québec, Canada
| | - Chen-Hsuin Lee
- Division of Infection & Immunity, University College London, London, United Kingdom
| | - Janos Kriston-Vizi
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Robin Ketteler
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Andy Merritt
- Centre for Therapeutics Discovery, MRC Technology, Mill Hill, London, United Kingdom
| | - Jean-Pierre Routy
- McGill University Health Centre, Glen site, Montreal, Québec, Canada
| | - Petronela Ancuta
- Department of Microbiology, Infectiology and Immunology, Faculty of Medicine, University of Montreal and the Research Centre of the CHUM, Montreal, Québec, Canada
| | | | - Ariberto Fassati
- Division of Infection & Immunity, University College London, London, United Kingdom
- * E-mail:
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Phosphorylation of the HIV-1 capsid by MELK triggers uncoating to promote viral cDNA synthesis. PLoS Pathog 2017; 13:e1006441. [PMID: 28683086 PMCID: PMC5500366 DOI: 10.1371/journal.ppat.1006441] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 06/02/2017] [Indexed: 11/19/2022] Open
Abstract
Regulation of capsid disassembly is crucial for efficient HIV-1 cDNA synthesis after entry, yet host factors involved in this process remain largely unknown. Here, we employ genetic screening of human T-cells to identify maternal embryonic leucine zipper kinase (MELK) as a host factor required for optimal uncoating of the HIV-1 core to promote viral cDNA synthesis. Depletion of MELK inhibited HIV-1 cDNA synthesis with a concomitant delay of capsid disassembly. MELK phosphorylated Ser-149 of the capsid in the multimerized HIV-1 core, and a mutant virus carrying a phosphorylation-mimetic amino-acid substitution of Ser-149 underwent premature capsid disassembly and earlier HIV-1 cDNA synthesis, and eventually failed to enter the nucleus. Moreover, a small-molecule MELK inhibitor reduced the efficiency of HIV-1 replication in peripheral blood mononuclear cells in a dose-dependent manner. These results reveal a previously unrecognized mechanism of HIV-1 capsid disassembly and implicate MELK as a potential target for anti-HIV therapy. Phosphorylation of the HIV-1 capsid has long been known to regulate viral uncoating and cDNA synthesis processes, but the cellular kinases responsible for this have remained unidentified. Here, we report that a host cell kinase MELK dictates optimal capsid disassembly through phosphorylation of Ser-149 in the multimerized HIV-1 core, which leads to efficient viral cDNA synthesis in target cells. The phosphorylation-mimetic capsid mutation of Ser-149 caused aberrant capsid disassembly and too-early completion of reverse transcription, and impeded nuclear entry of HIV-1 cDNA, suggesting the importance of well-ordered capsid disassembly in the early stages of viral replication. This discovery will facilitate understanding of the functional link among virus uncoating, reverse transcription and nuclear entry, and is expected to contribute to developing a novel strategy for AIDS therapy.
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Capsid-Dependent Host Factors in HIV-1 Infection. Trends Microbiol 2017; 25:741-755. [PMID: 28528781 DOI: 10.1016/j.tim.2017.04.004] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 03/31/2017] [Accepted: 04/18/2017] [Indexed: 11/20/2022]
Abstract
After invasion of a susceptible target cell, HIV-1 completes the early phase of its life cycle upon integration of reverse-transcribed viral DNA into host chromatin. The viral capsid, a conical shell encasing the viral ribonucleoprotein complex, along with its constitutive capsid protein, plays essential roles at virtually every step in the early phase of the viral life cycle. Recent work has begun to reveal how the viral capsid interacts with specific cellular proteins to promote these processes. At the same time, cellular restriction factors target the viral capsid to thwart infection. Comprehensive understanding of capsid-host interactions that promote or impede HIV-1 infection may provide unique insight to exploit for novel therapeutic interventions.
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Analysis of the functional compatibility of SIV capsid sequences in the context of the FIV gag precursor. PLoS One 2017; 12:e0177297. [PMID: 28475623 PMCID: PMC5419655 DOI: 10.1371/journal.pone.0177297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Accepted: 04/25/2017] [Indexed: 02/02/2023] Open
Abstract
The formation of immature lentiviral particles is dependent on the multimerization of the Gag polyprotein at the plasma membrane of the infected cells. One key player in the virus assembly process is the capsid (CA) domain of Gag, which establishes the protein-protein interactions that give rise to the hexagonal lattice of Gag molecules in the immature virion. To gain a better understanding of the functional equivalence between the CA proteins of simian and feline immunodeficiency viruses (SIV and FIV, respectively), we generated a series of chimeric FIV Gag proteins in which the CA-coding region was partially or totally replaced by its SIV counterpart. All the FIV Gag chimeras were found to be assembly-defective; however, all of them are able to interact with wild-type SIV Gag and be recruited into extracellular virus-like particles, regardless of the SIV CA sequences present in the chimeric FIV Gag. The results presented here markedly contrast with our previous findings showing that chimeric SIVs carrying FIV CA-derived sequences are assembly-competent. Overall, our data support the notion that although the SIV and FIV CA proteins share 51% amino acid sequence similarity and exhibit a similar organization, i.e., an N-terminal domain joined by a flexible linker to a C-terminal domain, their functional exchange between these different lentiviruses is strictly dependent on the context of the recipient Gag precursor.
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35
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The flavivirus capsid protein: Structure, function and perspectives towards drug design. Virus Res 2017; 227:115-123. [DOI: 10.1016/j.virusres.2016.10.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 09/29/2016] [Accepted: 10/12/2016] [Indexed: 12/12/2022]
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Bergman S, Lezon TR. Modeling global changes induced by local perturbations to the HIV-1 capsid. J Mol Graph Model 2016; 71:218-226. [PMID: 27951510 DOI: 10.1016/j.jmgm.2016.12.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 11/04/2016] [Accepted: 12/01/2016] [Indexed: 02/02/2023]
Abstract
The HIV-1 capsid is a conical protein shell made up of hexamers and pentamers of the capsid protein. The capsid houses the viral genome and replication machinery, and its opening, or uncoating, within the host cell marks a critical step in the HIV-1 lifecycle. Binding of host factors such as TRIM5α and cyclophilin A (CypA) can alter the capsid's stability, accelerating or delaying the onset of uncoating and disrupting infectivity. We employ coarse-grained computational modeling to investigate the effects of point mutations and host factor binding on HIV-1 capsid stability. We find that the largest fluctuations occur in the low-curvature regions of the capsid, and that its structural dynamics are affected by perturbations at the inter-hexamer interfaces and near the CypA binding loop, suggesting roles for these features in capsid stability. Our models show that linking capsid proteins across hexamers attenuates vibration in the low-curvature regions of the capsid, but that linking within hexamers does not. These results indicate a possible mechanism through which CypA binding alters capsid stability and highlight the utility of coarse-grained network modeling for understanding capsid mechanics.
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Affiliation(s)
- Shana Bergman
- Department of Computational and Systems Biology, University of Pittsburgh, Suite 3064 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15260, USA.
| | - Timothy R Lezon
- Department of Computational and Systems Biology, University of Pittsburgh, Suite 3064 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15260, USA; University of Pittsburgh Drug Discovery Institute, University of Pittsburgh, W965 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, PA 15261, USA.
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Opp S, Fricke T, Shepard C, Kovalskyy D, Bhattacharya A, Herkules F, Ivanov DN, Kim B, Valle-Casuso J, Diaz-Griffero F. The small-molecule 3G11 inhibits HIV-1 reverse transcription. Chem Biol Drug Des 2016; 89:608-618. [PMID: 27748043 DOI: 10.1111/cbdd.12886] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/10/2016] [Accepted: 10/09/2016] [Indexed: 12/20/2022]
Abstract
The small-molecule 6-(tert-butyl)-4-phenyl-4-(trifluoromethyl)-1H,3H-1,3,5-triazin-2-one (3G11) inhibits HIV-1 replication in the human T cell line MT-2. Here, we showed that 3G11 specifically and potently blocks HIV-1 infection. By contrast, 3G11 did not block other retroviruses such as HIV-2, simian immunodeficiency virus (SIVmac ), bovine immunodeficiency virus, feline immunodeficiency virus, equine infectious anemia virus, N-tropic murine leukemia virus, B-tropic murine leukemia virus, and Moloney murine leukemia virus. Analysis of DNA metabolism by real-time PCR revealed that 3G11 blocks the formation of HIV-1 late reverse transcripts during infection prior to the first-strand transfer step. In agreement, an in vitro assay revealed that 3G11 blocks the enzymatic activity of HIV-1 reverse transcriptase as strong as nevirapine. Docking of 3G11 to the HIV-1 reverse transcriptase enzyme suggested a direct interaction between residue L100 and 3G11. In agreement, an HIV-1 virus bearing the reverse transcriptase change L100I renders HIV-1 resistant to 3G11, which suggested that the reverse transcriptase enzyme is the viral determinant for HIV-1 sensitivity to 3G11. Although NMR experiments revealed that 3G11 binds to the HIV-1 capsid, functional experiments suggested that capsid is not the viral determinant for sensitivity to 3G11. Overall, we described a novel non-nucleoside reverse transcription inhibitor that blocks HIV-1 infection.
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Affiliation(s)
- Silvana Opp
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Thomas Fricke
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Caitlin Shepard
- Department of Pediatrics, Emory University, Atlanta, GA, USA
| | - Dmytro Kovalskyy
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, USA
| | - Akash Bhattacharya
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, USA
| | - Frank Herkules
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, USA
| | - Dmitri N Ivanov
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, USA
| | - Baek Kim
- Department of Pediatrics, Emory University, Atlanta, GA, USA
| | - Jose Valle-Casuso
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Felipe Diaz-Griffero
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
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Interactions of Prototype Foamy Virus Capsids with Host Cell Polo-Like Kinases Are Important for Efficient Viral DNA Integration. PLoS Pathog 2016; 12:e1005860. [PMID: 27579920 PMCID: PMC5006980 DOI: 10.1371/journal.ppat.1005860] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 08/11/2016] [Indexed: 01/31/2023] Open
Abstract
Unlike for other retroviruses, only a few host cell factors that aid the replication of foamy viruses (FVs) via interaction with viral structural components are known. Using a yeast-two-hybrid (Y2H) screen with prototype FV (PFV) Gag protein as bait we identified human polo-like kinase 2 (hPLK2), a member of cell cycle regulatory kinases, as a new interactor of PFV capsids. Further Y2H studies confirmed interaction of PFV Gag with several PLKs of both human and rat origin. A consensus Ser-Thr/Ser-Pro (S-T/S-P) motif in Gag, which is conserved among primate FVs and phosphorylated in PFV virions, was essential for recognition by PLKs. In the case of rat PLK2, functional kinase and polo-box domains were required for interaction with PFV Gag. Fluorescently-tagged PFV Gag, through its chromatin tethering function, selectively relocalized ectopically expressed eGFP-tagged PLK proteins to mitotic chromosomes in a Gag STP motif-dependent manner, confirming a specific and dominant nature of the Gag-PLK interaction in mammalian cells. The functional relevance of the Gag-PLK interaction was examined in the context of replication-competent FVs and single-round PFV vectors. Although STP motif mutated viruses displayed wild type (wt) particle release, RNA packaging and intra-particle reverse transcription, their replication capacity was decreased 3-fold in single-cycle infections, and up to 20-fold in spreading infections over an extended time period. Strikingly similar defects were observed when cells infected with single-round wt Gag PFV vectors were treated with a pan PLK inhibitor. Analysis of entry kinetics of the mutant viruses indicated a post-fusion defect resulting in delayed and reduced integration, which was accompanied with an enhanced preference to integrate into heterochromatin. We conclude that interaction between PFV Gag and cellular PLK proteins is important for early replication steps of PFV within host cells. Viruses are masters at exploiting host cell machineries for their replication. For human immunodeficiency virus type 1 (HIV-1), the best-studied representative of the Orthoretrovirinae subfamily from the genus lentiviruses, numerous important virus-host interactions have been described. In contrast, only a few cellular proteins are known to influence the replication of foamy viruses (FVs, also known as spumaviruses), an intriguing type of complex retrovirus of the Spumaretrovirinae subfamily that combines features of both retroviruses and hepadnaviruses in its replication strategy. Given the increasing interest in FVs as gene transfer tools and their unique status within the retrovirus family, this discrepancy urged the identification of novel host cell interaction partners of FV structural components. This study focused on prototype FV (PFV), the best-characterized member of FVs, and its capsid protein, Gag, as the central player of viral replication. Members of the mitosis-regulatory, polo-like kinase (PLK) family were identified as novel Gag binding partners. The Gag interaction with PLK1 (and possibly also PLK2) facilitated efficient PFV genome integration into host chromatin, ensuring successful replication and viral spread in infected target cell cultures. Collectively, our results elucidate the first link between cell cycle regulatory networks and the mitosis-dependent PFV integration process.
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Tóth F, Kádas J, Mótyán JA, Tőzsér J. Effect of internal cleavage site mutations in human immunodeficiency virus type 1 capsid protein on its structure and function. FEBS Open Bio 2016; 6:847-59. [PMID: 27516963 PMCID: PMC4971840 DOI: 10.1002/2211-5463.12094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/12/2016] [Accepted: 05/26/2016] [Indexed: 12/13/2022] Open
Abstract
The capsid protein of the human immunodeficiency virus type 1 has been found to be a substrate of the retroviral protease in vitro, and its processing was predicted to be strongly dependent on a pH‐induced conformational change. Several protease cleavage sites have been identified within the capsid protein, but the importance of its cleavage by the viral protease at the early phase of infection is controversial. To confirm the relevance of this process, we aimed to design, produce, and characterize mutant capsid proteins, in which the protein susceptibility toward HIV‐1 protease is altered without affecting other steps of the viral life cycle. Our results indicate that while the introduced mutations changed the cleavage rate at the mutated sites of the capsid protein by HIV‐1 protease, some of them caused only negligible or moderate structural changes (A78V, L189F, and L189I). However, the effects of other mutations (W23A, A77P, and L189P) were dramatic, as assessed by secondary structure determination or cyclophilin A‐binding assay. Based on our observations, the L189F mutant capsid remains structurally and functionally unchanged and may therefore be the best candidate for use in studies aimed at better understanding the role of the protease in the early postentry events of viral infection or retrovirus‐mediated gene transduction.
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Affiliation(s)
- Ferenc Tóth
- Department of Biochemistry and Molecular Biology Faculty of Medicine University of Debrecen Hungary
| | - János Kádas
- Department of Biochemistry and Molecular Biology Faculty of Medicine University of Debrecen Hungary
| | - János András Mótyán
- Department of Biochemistry and Molecular Biology Faculty of Medicine University of Debrecen Hungary
| | - József Tőzsér
- Department of Biochemistry and Molecular Biology Faculty of Medicine University of Debrecen Hungary
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Capsid-CPSF6 Interaction Is Dispensable for HIV-1 Replication in Primary Cells but Is Selected during Virus Passage In Vivo. J Virol 2016; 90:6918-6935. [PMID: 27307565 DOI: 10.1128/jvi.00019-16] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 05/08/2016] [Indexed: 12/15/2022] Open
Abstract
UNLABELLED Cleavage and polyadenylation specificity factor subunit 6 (CPSF6), a host factor that interacts with the HIV-1 capsid (CA) protein, is implicated in diverse functions during the early part of the HIV-1 life cycle, including uncoating, nuclear entry, and integration targeting. Preservation of CA binding to CPSF6 in vivo suggests that this interaction is fine-tuned for efficient HIV-1 replication in physiologically relevant settings. Nevertheless, this possibility has not been formally examined. To assess the requirement for optimal CPSF6-CA binding during infection of primary cells and in vivo, we utilized a novel CA mutation, A77V, that significantly reduced CA binding to CPSF6. The A77V mutation rendered HIV-1 largely independent from TNPO3, NUP358, and NUP153 for infection and altered the integration site preference of HIV-1 without any discernible effects during the late steps of the virus life cycle. Surprisingly, the A77V mutant virus maintained the ability to replicate in monocyte-derived macrophages, primary CD4(+) T cells, and humanized mice at a level comparable to that for the wild-type (WT) virus. Nonetheless, revertant viruses that restored the WT CA sequence and hence CA binding to CPSF6 emerged in three out of four A77V-infected animals. These results suggest that the optimal interaction of CA with CPSF6, though not absolutely essential for HIV-1 replication in physiologically relevant settings, confers a significant fitness advantage to the virus and thus is strictly conserved among naturally circulating HIV-1 strains. IMPORTANCE CPSF6 interacts with the HIV-1 capsid (CA) protein and has been implicated in nuclear entry and integration targeting. Preservation of CPSF6-CA binding across various HIV-1 strains suggested that the optimal interaction between CA and CPSF6 is critical during HIV-1 replication in vivo Here, we identified a novel HIV-1 capsid mutant that reduces binding to CPSF6, is largely independent from the known cofactors for nuclear entry, and alters integration site preference. Despite these changes, virus carrying this mutation replicated in humanized mice at levels indistinguishable from those of the wild-type virus. However, in the majority of the animals, the mutant virus reverted back to the wild-type sequence, hence restoring the wild-type level of CA-CPSF6 interactions. These results suggest that optimal binding of CA to CPSF6 is not absolutely essential for HIV-1 replication in vivo but provides a fitness advantage that leads to the widespread usage of CPSF6 by HIV-1 in vivo.
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Ma Y, He Z, Tan T, Li W, Zhang Z, Song S, Zhang X, Hu Q, Zhou P, Wu Y, Zhang XE, Cui Z. Real-Time Imaging of Single HIV-1 Disassembly with Multicolor Viral Particles. ACS NANO 2016; 10:6273-82. [PMID: 27253587 DOI: 10.1021/acsnano.6b02462] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Viral disassembly is poorly understood and related to the infection mechanism. However, directly observing the process in living cells remains technically challenging. In this study, the genome RNA, capsid, and matrix protein of the HIV-1 virus were labeled with a Ru(II) complex ([Ru(phen)2(dppz)](2+)), the TC-FlAsH/ReAsH system, and EGFP/ECFP, respectively. Using the multicolored virus and single-particle imaging, we were able to track the sequential disassembly process of single HIV-1 virus particles in live host cells. Approximately 0.1% of viral particles were observed to undergo a sequential disassembly process at 60-120 min post infection. The timing and efficiency of the disassembly were influenced by the cellular factor CypA and reverse transcription. The findings facilitate a better understanding of the processes governing the HIV-1 lifecycle. The multicolor labeling protocol developed in this study may find many applications involving virus-host-cell interactions.
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Affiliation(s)
- Yingxin Ma
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, PR China
| | - Zhike He
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Sciences, Wuhan University , Wuhan 430072, PR China
| | - Tianwei Tan
- Beijing Key Lab of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology , Beijing 100029, PR China
| | - Wei Li
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
| | - Zhiping Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
| | - Shuang Song
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
| | - Xiaowei Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
| | - Qinxue Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
| | - Peng Zhou
- Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Sciences, Wuhan University , Wuhan 430072, PR China
| | - Yuntao Wu
- National Center for Biodefense and Infectious Diseases, Department of Molecular and Microbiology, George Mason University , Manassas, Virginia 22030, United States
| | - Xian-En Zhang
- State Key Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences , Beijing 100101, PR China
| | - Zongqiang Cui
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences , Wuhan 430071, PR China
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42
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Francis AC, Marin M, Shi J, Aiken C, Melikyan GB. Time-Resolved Imaging of Single HIV-1 Uncoating In Vitro and in Living Cells. PLoS Pathog 2016; 12:e1005709. [PMID: 27322072 PMCID: PMC4913920 DOI: 10.1371/journal.ppat.1005709] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 05/25/2016] [Indexed: 12/17/2022] Open
Abstract
Disassembly of the cone-shaped HIV-1 capsid in target cells is a prerequisite for establishing a life-long infection. This step in HIV-1 entry, referred to as uncoating, is critical yet poorly understood. Here we report a novel strategy to visualize HIV-1 uncoating using a fluorescently tagged oligomeric form of a capsid-binding host protein cyclophilin A (CypA-DsRed), which is specifically packaged into virions through the high-avidity binding to capsid (CA). Single virus imaging reveals that CypA-DsRed remains associated with cores after permeabilization/removal of the viral membrane and that CypA-DsRed and CA are lost concomitantly from the cores in vitro and in living cells. The rate of loss is modulated by the core stability and is accelerated upon the initiation of reverse transcription. We show that the majority of single cores lose CypA-DsRed shortly after viral fusion, while a small fraction remains intact for several hours. Single particle tracking at late times post-infection reveals a gradual loss of CypA-DsRed which is dependent on reverse transcription. Uncoating occurs both in the cytoplasm and at the nuclear membrane. Our novel imaging assay thus enables time-resolved visualization of single HIV-1 uncoating in living cells, and reveals the previously unappreciated spatio-temporal features of this incompletely understood process. HIV-1 genome and key enzymes required for establishing productive infection are encased in a cone-shaped shell made of the capsid protein (CA). After being released into the cytosol of target cells, the cone-shaped core complex undergoes a series of carefully orchestrated steps, including uncoating (loss of CA). HIV-1 uncoating remains poorly understood, due in part to the lack of direct assays enabling studies of this process in living cells. Here, we introduce a novel strategy for labeling the HIV-1 capsid without genetically modifying the CA protein. We designed a novel fluorescent cyclophilin A construct that binds the capsid with an extremely high avidity and (1) efficiently incorporates into virions without compromising infectivity; (2) remains bound to cores after viral fusion; and (3) is lost from post-fusion cores along with CA. The novel imaging assay provides new insights into the kinetics and spatial distribution of HIV-1 uncoating in living cells.
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Affiliation(s)
- Ashwanth C Francis
- Department of Pediatric, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Mariana Marin
- Department of Pediatric, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Jiong Shi
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center. Nashville, Tennessee, United States of America
| | - Christopher Aiken
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center. Nashville, Tennessee, United States of America
| | - Gregory B Melikyan
- Department of Pediatric, Emory University School of Medicine, Atlanta, Georgia, United States of America.,Children's Healthcare of Atlanta, Atlanta, Georgia, United States of America
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43
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Roles of Capsid-Interacting Host Factors in Multimodal Inhibition of HIV-1 by PF74. J Virol 2016; 90:5808-5823. [PMID: 27076642 DOI: 10.1128/jvi.03116-15] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 04/02/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The viral capsid of HIV-1 interacts with a number of host factors to orchestrate uncoating and regulate downstream events, such as reverse transcription, nuclear entry, and integration site targeting. PF-3450074 (PF74), an HIV-1 capsid-targeting low-molecular-weight antiviral compound, directly binds to the capsid (CA) protein at a site also utilized by host cell proteins CPSF6 and NUP153. Here, we found that the dose-response curve of PF74 is triphasic, consisting of a plateau and two inhibitory phases of different slope values, consistent with a bimodal mechanism of drug action. High PF74 concentrations yielded a steep curve with the highest slope value among different classes of known antiretrovirals, suggesting a dose-dependent, cooperative mechanism of action. CA interactions with both CPSF6 and cyclophilin A (CypA) were essential for the unique dose-response curve. A shift of the steep curve at lower drug concentrations upon blocking the CA-CypA interaction suggests a protective role for CypA against high concentrations of PF74. These findings, highlighting the unique characteristics of PF74, provide a model in which its multimodal mechanism of action of both noncooperative and cooperative inhibition by PF74 is regulated by interactions of cellular proteins with incoming viral capsids. IMPORTANCE PF74, a novel capsid-targeting antiviral against HIV-1, shares its binding site in the viral capsid protein (CA) with the host factors CPSF6 and NUP153. This work reveals that the dose-response curve of PF74 consists of two distinct inhibitory phases that are differentially regulated by CA-interacting host proteins. PF74's potency depended on these CA-binding factors at low doses. In contrast, the antiviral activity of high PF74 concentrations was attenuated by cyclophilin A. These observations provide novel insights into both the mechanism of action of PF74 and the roles of host factors during the early steps of HIV-1 infection.
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44
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Chen NY, Zhou L, Gane PJ, Opp S, Ball NJ, Nicastro G, Zufferey M, Buffone C, Luban J, Selwood D, Diaz-Griffero F, Taylor I, Fassati A. HIV-1 capsid is involved in post-nuclear entry steps. Retrovirology 2016; 13:28. [PMID: 27107820 PMCID: PMC4842275 DOI: 10.1186/s12977-016-0262-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 04/14/2016] [Indexed: 11/17/2022] Open
Abstract
Background HIV-1 capsid influences viral uncoating and nuclear import. Some capsid is detected in the nucleus but it is unclear if it has any function. We reported that the antibiotic Coumermycin-A1 (C-A1) inhibits HIV-1 integration and that a capsid mutation confers resistance to C-A1, suggesting that capsid might affect post-nuclear entry steps. Results Here we report that C-A1 inhibits HIV-1 integration in a capsid-dependent way. Using molecular docking, we identify an extended binding pocket delimited by two adjacent capsid monomers where C-A1 is predicted to bind. Isothermal titration calorimetry confirmed that C-A1 binds to hexameric capsid. Cyclosporine washout assays in Jurkat CD4+ T cells expressing engineered human TRIMCyp showed that C-A1 causes faster and greater escape from TRIMCyp restriction. Sub-cellular fractionation showed that small amounts of capsid accumulated in the nuclei of infected cells and C-A1 reduced the nuclear capsid. A105S and N74D capsid mutant viruses did not accumulate capsid in the nucleus, irrespective of C-A1 treatment. Depletion of Nup153, a nucleoporin located at the nuclear side of the nuclear pore that binds to HIV-1 capsid, made the virus less susceptible to TRIMCyp restriction, suggesting that Nup153 may help maintain some integrity of the viral core in the nucleus. Furthermore C-A1 increased binding of CPSF6, a nuclear protein, to capsid. Conclusions Our results indicate that capsid is involved in post-nuclear entry steps preceding integration. Electronic supplementary material The online version of this article (doi:10.1186/s12977-016-0262-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nan-Yu Chen
- Division of Infection and Immunity, University College London, Cruciform Building, 90 Gower Street, London, WC1E 6BT, UK.,Division of Infectious Diseases, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 5 Fuhsing Street, Kueishan, Taoyuan, 333, Taiwan
| | - Lihong Zhou
- Division of Infection and Immunity, University College London, Cruciform Building, 90 Gower Street, London, WC1E 6BT, UK.,Genome Damage and Stability Centre, University of Sussex, Science Park Road, Falmer, Brighton, BN1 9RQ, UK
| | - Paul J Gane
- Medicinal Chemistry Group, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK.,Chemical Computing Group, St. John's Innovation Centre, Cowley Road, Cambridge, CB4 0WS, UK
| | - Silvana Opp
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Neil J Ball
- Mill Hill Laboratory, The Francis Crick Institute, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - Giuseppe Nicastro
- Mill Hill Laboratory, The Francis Crick Institute, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - Madeleine Zufferey
- Department of Microbiology and Molecular Medicine, University of Geneva, 1 Rue Michel Servet, CH-1211, Geneva, Switzerland.,Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Biotech 2, Suite 319, Worcester, MA, 01605, USA
| | - Cindy Buffone
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Jeremy Luban
- Department of Microbiology and Molecular Medicine, University of Geneva, 1 Rue Michel Servet, CH-1211, Geneva, Switzerland.,Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Biotech 2, Suite 319, Worcester, MA, 01605, USA.,Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 373 Plantation Street, Biotech 2, Suite 319, Worcester, MA, 01605, USA
| | - David Selwood
- Medicinal Chemistry Group, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - Felipe Diaz-Griffero
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ian Taylor
- Mill Hill Laboratory, The Francis Crick Institute, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - Ariberto Fassati
- Division of Infection and Immunity, University College London, Cruciform Building, 90 Gower Street, London, WC1E 6BT, UK.
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Abstract
Long terminal repeat (LTR) retrotransposons constitute significant fractions of many eukaryotic genomes. Two ancient families are Ty1/Copia (Pseudoviridae) and Ty3/Gypsy (Metaviridae). The Ty3/Gypsy family probably gave rise to retroviruses based on the domain order, similarity of sequences, and the envelopes encoded by some members. The Ty3 element of Saccharomyces cerevisiae is one of the most completely characterized elements at the molecular level. Ty3 is induced in mating cells by pheromone stimulation of the mitogen-activated protein kinase pathway as cells accumulate in G1. The two Ty3 open reading frames are translated into Gag3 and Gag3-Pol3 polyprotein precursors. In haploid mating cells Gag3 and Gag3-Pol3 are assembled together with Ty3 genomic RNA into immature virus-like particles in cellular foci containing RNA processing body proteins. Virus-like particle Gag3 is then processed by Ty3 protease into capsid, spacer, and nucleocapsid, and Gag3-Pol3 into those proteins and additionally, protease, reverse transcriptase, and integrase. After haploid cells mate and become diploid, genomic RNA is reverse transcribed into cDNA. Ty3 integration complexes interact with components of the RNA polymerase III transcription complex resulting in Ty3 integration precisely at the transcription start site. Ty3 activation during mating enables proliferation of Ty3 between genomes and has intriguing parallels with metazoan retrotransposon activation in germ cell lineages. Identification of nuclear pore, DNA replication, transcription, and repair host factors that affect retrotransposition has provided insights into how hosts and retrotransposons interact to balance genome stability and plasticity.
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46
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Ranjan N, Rodnina MV. tRNA wobble modifications and protein homeostasis. ACTA ACUST UNITED AC 2016; 4:e1143076. [PMID: 27335723 DOI: 10.1080/21690731.2016.1143076] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/28/2015] [Accepted: 01/12/2016] [Indexed: 12/20/2022]
Abstract
tRNA is a central component of the protein synthesis machinery in the cell. In living cells, tRNAs undergo numerous post-transcriptional modifications. In particular, modifications at the anticodon loop play an important role in ensuring efficient protein synthesis, maintaining protein homeostasis, and helping cell adaptation and survival. Hypo-modification of the wobble position of the tRNA anticodon loop is of particular relevance for translation regulation and is implicated in various human diseases. In this review we summarize recent evidence of how methyl and thiol modifications in eukaryotic tRNA at position 34 affect cellular fitness and modulate regulatory circuits at normal conditions and under stress.
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Affiliation(s)
- Namit Ranjan
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry , Göttingen, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry , Göttingen, Germany
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47
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Bai R, Zhang XJ, Li YL, Liu JP, Zhang HB, Xiao WL, Pu JX, Sun HD, Zheng YT, Liu LX. SJP-L-5, a novel small-molecule compound, inhibits HIV-1 infection by blocking viral DNA nuclear entry. BMC Microbiol 2015; 15:274. [PMID: 26630969 PMCID: PMC4667461 DOI: 10.1186/s12866-015-0605-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 11/24/2015] [Indexed: 11/15/2022] Open
Abstract
Background Small-molecule compounds that inhibit human immunodeficiency virus type 1 (HIV-1) infection can be used not only as drug candidates, but also as reagents to dissect the life cycle of the virus. Thus, it is desirable to have an arsenal of such compounds that inhibit HIV-1 infection by various mechanisms. Until now, only a few small-molecule compounds that inhibit nuclear entry of viral DNA have been documented. Results We identified a novel, small-molecule compound, SJP-L-5, that inhibits HIV-1 infection. SJP-L-5 is a nitrogen-containing, biphenyl compound whose synthesis was based on the dibenzocyclooctadiene lignan gomisin M2, an anti-HIV bioactive compound isolated from Schisandra micrantha A. C. Smith. SJP-L-5 displayed relatively low cytotoxicity (50 % cytoxicity concentrations were greater than 200 μg/ml) and high antiviral activity against a variety of HIV strains (50 % effective concentrations (EC50)) of HIV-1 laboratory-adapted strains ranged from 0.16–0.97 μg/ml; EC50s of primary isolates ranged from 1.96–5.33 μg/ml). Analyses of the viral DNA synthesis indicated that SJP-L-5 specifically blocks the entry of the HIV-1 pre-integration complex (PIC) into the nucleus. Further results implicated that SJP-L-5 inhibits the disassembly of HIV-1 particulate capsid in the cytoplasm of the infected cells. Conclusions SJP-L-5 is a novel small-molecule compound that inhibits HIV-1 nuclear entry by blocking the disassembly of the viral core. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0605-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ru Bai
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
| | - Xing-Jie Zhang
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and the Kunming Institute of Zoology of the Chinese Academy of Sciences, Kunming, 650223, P. R. China.
| | - Yan-Li Li
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
| | - Jing-Ping Liu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Hong-Bin Zhang
- Key Laboratory of Medicinal Chemistry for Natural Resources, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, P. R. China.
| | - Wei-Lie Xiao
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Jian-Xin Pu
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Han-Dong Sun
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P. R. China.
| | - Yong-Tang Zheng
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and the Kunming Institute of Zoology of the Chinese Academy of Sciences, Kunming, 650223, P. R. China.
| | - Li-Xin Liu
- Sun Yat-Sen University, Guangzhou, 510275, P. R. China.
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48
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Composite Sequence-Structure Stability Models as Screening Tools for Identifying Vulnerable Targets for HIV Drug and Vaccine Development. Viruses 2015; 7:5718-35. [PMID: 26556362 PMCID: PMC4664974 DOI: 10.3390/v7112901] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/19/2015] [Accepted: 10/23/2015] [Indexed: 02/03/2023] Open
Abstract
Rapid evolution and high sequence diversity enable Human Immunodeficiency Virus (HIV) populations to acquire mutations to escape antiretroviral drugs and host immune responses, and thus are major obstacles for the control of the pandemic. One strategy to overcome this problem is to focus drugs and vaccines on regions of the viral genome in which mutations are likely to cripple function through destabilization of viral proteins. Studies relying on sequence conservation alone have had only limited success in determining critically important regions. We tested the ability of two structure-based computational models to assign sites in the HIV-1 capsid protein (CA) that would be refractory to mutational change. The destabilizing mutations predicted by these models were rarely found in a database of 5811 HIV-1 CA coding sequences, with none being present at a frequency greater than 2%. Furthermore, 90% of variants with the low predicted stability (from a set of 184 CA variants whose replication fitness or infectivity has been studied in vitro) had aberrant capsid structures and reduced viral infectivity. Based on the predicted stability, we identified 45 CA sites prone to destabilizing mutations. More than half of these sites are targets of one or more known CA inhibitors. The CA regions enriched with these sites also overlap with peptides shown to induce cellular immune responses associated with lower viral loads in infected individuals. Lastly, a joint scoring metric that takes into account both sequence conservation and protein structure stability performed better at identifying deleterious mutations than sequence conservation or structure stability information alone. The computational sequence-structure stability approach proposed here might therefore be useful for identifying immutable sites in a protein for experimental validation as potential targets for drug and vaccine development.
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Jeng MY, Ali I, Ott M. Manipulation of the host protein acetylation network by human immunodeficiency virus type 1. Crit Rev Biochem Mol Biol 2015; 50:314-25. [PMID: 26329395 DOI: 10.3109/10409238.2015.1061973] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Over the past 15 years, protein acetylation has emerged as a globally important post-translational modification that fine-tunes major cellular processes in many life forms. This dynamic regulatory system is critical both for complex eukaryotic cells and for the viruses that infect them. HIV-1 accesses the host acetylation network by interacting with several key enzymes, thereby promoting infection at multiple steps during the viral life cycle. Inhibitors of host histone deacetylases and bromodomain-containing proteins are now being pursued as therapeutic strategies to enhance current antiretroviral treatment. As more acetylation-targeting compounds are reaching clinical trials, it is time to review the role of reversible protein acetylation in HIV-infected CD4(+) T cells.
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Affiliation(s)
- Mark Y Jeng
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
| | - Ibraheem Ali
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
| | - Melanie Ott
- a Gladstone Institute of Virology and Immunology , San Francisco , CA , USA and.,b Department of Medicine , University of California , San Francisco , CA , USA
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Hou H, Wang JZ, Liu BG, Zhang T. Pin1 liberates the human immunodeficiency virus type-1 (HIV-1): Must we stop it? Gene 2015; 565:9-14. [PMID: 25913034 DOI: 10.1016/j.gene.2015.04.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 03/07/2015] [Accepted: 04/20/2015] [Indexed: 11/16/2022]
Abstract
Acquired immune deficiency syndrome (AIDS) is mainly caused by the human immunodeficiency virus type-1 (HIV-1). To our knowledge, this is the first review focusing on the vital role of Pin1 in the infection of HIV-1 and the development of AIDS. We and others have demonstrated that Pin1, the only known cis-to-trans isomerase recognizing the pThr/pSer-Pro motifs in proteins, plays striking roles in several human diseases. Interestingly, recent evidence gradually indicates that Pin1 regulates several key steps of the life cycle of HIV-1, including the uncoating of the HIV-1 core, the reverse transcription of the RNA genome of HIV-1, and the integration of the HIV-1 cDNA into human chromosomes. Whereas inhibiting Pin1 suppresses all of these key steps and attenuates the replication of HIV-1, at the same time different PIN1 gene variants are correlated with the susceptibility to HIV-1 infection. Furthermore, Pin1 potentially promotes HIV-1 infection by activating multiple oncogenes and inactivating multiple tumor suppressors, extending the life span of HIV-infected cells. These descriptions suggest Pin1 as a promising therapeutic target for the prevention of HIV-1 and highlight the possibility of blocking the development of AIDS by Pin1 inhibitors.
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Affiliation(s)
- Hai Hou
- Key Laboratory for Space Bioscience and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, Shaanxi, PR China
| | - Jing-Zhang Wang
- Affiliated Hospital, College of Medicine, Hebei University of Engineering, Handan 056002, Hebei, PR China.
| | - Bao-Guo Liu
- Affiliated Hospital, College of Medicine, Hebei University of Engineering, Handan 056002, Hebei, PR China
| | - Ting Zhang
- Affiliated Hospital, College of Medicine, Hebei University of Engineering, Handan 056002, Hebei, PR China
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