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Liang T, Li G, Lu Y, Hu M, Ma X. The Involvement of Ubiquitination and SUMOylation in Retroviruses Infection and Latency. Viruses 2023; 15:v15040985. [PMID: 37112965 PMCID: PMC10144533 DOI: 10.3390/v15040985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Retroviruses, especially the pathogenic human immunodeficiency virus type 1 (HIV-1), have severely threatened human health for decades. Retroviruses can form stable latent reservoirs via retroviral DNA integration into the host genome, and then be temporarily transcriptional silencing in infected cells, which makes retroviral infection incurable. Although many cellular restriction factors interfere with various steps of the life cycle of retroviruses and the formation of viral latency, viruses can utilize viral proteins or hijack cellular factors to evade intracellular immunity. Many post-translational modifications play key roles in the cross-talking between the cellular and viral proteins, which has greatly determined the fate of retroviral infection. Here, we reviewed recent advances in the regulation of ubiquitination and SUMOylation in the infection and latency of retroviruses, focusing on both host defense- and virus counterattack-related ubiquitination and SUMOylation system. We also summarized the development of ubiquitination- and SUMOylation-targeted anti-retroviral drugs and discussed their therapeutic potential. Manipulating ubiquitination or SUMOylation pathways by targeted drugs could be a promising strategy to achieve a "sterilizing cure" or "functional cure" of retroviral infection.
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Affiliation(s)
- Taizhen Liang
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Guojie Li
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Yunfei Lu
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Meilin Hu
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Xiancai Ma
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
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2
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Complex Relationships between HIV-1 Integrase and Its Cellular Partners. Int J Mol Sci 2022; 23:ijms232012341. [PMID: 36293197 PMCID: PMC9603942 DOI: 10.3390/ijms232012341] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/09/2022] [Accepted: 10/11/2022] [Indexed: 11/06/2022] Open
Abstract
RNA viruses, in pursuit of genome miniaturization, tend to employ cellular proteins to facilitate their replication. HIV-1, one of the most well-studied retroviruses, is not an exception. There is numerous evidence that the exploitation of cellular machinery relies on nucleic acid-protein and protein-protein interactions. Apart from Vpr, Vif, and Nef proteins that are known to regulate cellular functioning via interaction with cell components, another viral protein, integrase, appears to be crucial for proper virus-cell dialog at different stages of the viral life cycle. The goal of this review is to summarize and systematize existing data on known cellular partners of HIV-1 integrase and their role in the HIV-1 life cycle.
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3
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Rocchi C, Gouet P, Parissi V, Fiorini F. The C-Terminal Domain of HIV-1 Integrase: A Swiss Army Knife for the Virus? Viruses 2022; 14:v14071397. [PMID: 35891378 PMCID: PMC9316232 DOI: 10.3390/v14071397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/22/2022] [Accepted: 06/22/2022] [Indexed: 12/31/2022] Open
Abstract
Retroviral integrase is a multimeric enzyme that catalyzes the integration of reverse-transcribed viral DNA into the cellular genome. Beyond integration, the Human immunodeficiency virus type 1 (HIV-1) integrase is also involved in many other steps of the viral life cycle, such as reverse transcription, nuclear import, virion morphogenesis and proviral transcription. All these additional functions seem to depend on the action of the integrase C-terminal domain (CTD) that works as a molecular hub, interacting with many different viral and cellular partners. In this review, we discuss structural issues concerning the CTD, with particular attention paid to its interaction with nucleic acids. We also provide a detailed map of post-translational modifications and interaction with molecular partners.
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Affiliation(s)
- Cecilia Rocchi
- Molecular Microbiology and Structural Biochemistry (MMSB), CNRS, University of Lyon 1, UMR 5086, 69367 Lyon, France; (C.R.); (P.G.)
- Viral DNA Integration and Chromatin Dynamics Network (DyNAVir), 33076 Bordeaux, France;
| | - Patrice Gouet
- Molecular Microbiology and Structural Biochemistry (MMSB), CNRS, University of Lyon 1, UMR 5086, 69367 Lyon, France; (C.R.); (P.G.)
- Viral DNA Integration and Chromatin Dynamics Network (DyNAVir), 33076 Bordeaux, France;
| | - Vincent Parissi
- Viral DNA Integration and Chromatin Dynamics Network (DyNAVir), 33076 Bordeaux, France;
- Fundamental Microbiology and Pathogenicity (MFP), CNRS, University of Bordeaux, UMR5234, 33405 Bordeaux, France
| | - Francesca Fiorini
- Molecular Microbiology and Structural Biochemistry (MMSB), CNRS, University of Lyon 1, UMR 5086, 69367 Lyon, France; (C.R.); (P.G.)
- Viral DNA Integration and Chromatin Dynamics Network (DyNAVir), 33076 Bordeaux, France;
- Correspondence: ; Tel.: +33-4-72722624; Fax: +33-4-72722616
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4
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Zhang Q, Wang S, Li W, Yau E, Hui H, Singh PK, Achuthan V, Young Karris MA, Engelman AN, Rana T. Genome-wide CRISPR/Cas9 transcriptional activation screen identifies a histone acetyltransferase inhibitor complex as a regulator of HIV-1 integration. Nucleic Acids Res 2022; 50:6687-6701. [PMID: 35713529 PMCID: PMC9262610 DOI: 10.1093/nar/gkac464] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 04/28/2022] [Accepted: 06/14/2022] [Indexed: 12/24/2022] Open
Abstract
The retrovirus human immunodeficiency virus-1 (HIV-1) is the causative agent of AIDS. Although treatment of HIV/AIDS with antiretroviral therapy provides suppression of viremia, latent reservoirs of integrated proviruses preclude cure by current antiviral treatments. Understanding the mechanisms of host-viral interactions may elucidate new treatment strategies. Here, we performed a CRISPR/Cas9 transcriptional activation screen using a high-complexity, genome-wide sgRNA library to identify cellular factors that inhibit HIV-1 infection of human CD4+ T cells. MT4 cells were transduced with a CRISPR/Cas9 sgRNA library and infected with nef-deficient HIV-1NL4-3 expressing ganciclovir-sensitive thymidine kinase, thus enabling selection of HIV-1-resistant cells for analysis of enriched sgRNAs. After validation of screen hits, multiple host factors essential for HIV-1 infection were identified, including SET (SET nuclear proto-oncogene) and ANP32A (acidic nuclear phosphoprotein 32A, PP32A), which together form a histone acetylase inhibitor complex. Using multiple human cell lines and peripheral blood mononuclear cells (PBMCs) from healthy donors and HIV-1-infected individuals, we demonstrate that SET depletion increased HIV-1 infectivity by augmenting DNA integration without significantly changing sites of integration. Conversely, SET overexpression decreased HIV-1 integration and infectivity. SET protein expression was significantly reduced in PBMCs from HIV-1-infected individuals and was downregulated by HIV-1 infection of healthy donor cells in vitro. Notably, HIV-1-induced downregulation of SET could be alleviated by inhibition of the protease granzyme A. Altogether, we have identified cellular inhibitors of HIV-1 infection on a genome-wide scale, which affords new insight into host-virus interactions and may provide new strategies for HIV-1 treatment.
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Affiliation(s)
| | | | - Wanyu Li
- Division of Genetics, Department of Pediatrics, Program in Immunology, Institute for Genomic Medicine, UCSD Center for AIDS Research, University of California San Diego, 9500 Gilman Drive MC 0762, La Jolla, CA 92093, USA
| | - Edwin Yau
- Division of Genetics, Department of Pediatrics, Program in Immunology, Institute for Genomic Medicine, UCSD Center for AIDS Research, University of California San Diego, 9500 Gilman Drive MC 0762, La Jolla, CA 92093, USA
| | - Hui Hui
- Division of Genetics, Department of Pediatrics, Program in Immunology, Institute for Genomic Medicine, UCSD Center for AIDS Research, University of California San Diego, 9500 Gilman Drive MC 0762, La Jolla, CA 92093, USA
| | - Parmit Kumar Singh
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02215, USA,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Vasudevan Achuthan
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02215, USA,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Maile Ann Young Karris
- Division of Infectious Diseases, Department of Medicine, UCSD Center for AIDS Research, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA 02215, USA,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Tariq M Rana
- To whom correspondence should be addressed. Tel: +1 858 246 1100; Fax: +1 858 246 1600;
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5
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Winans S, Goff SP. Mutations altering acetylated residues in the CTD of HIV-1 integrase cause defects in proviral transcription at early times after integration of viral DNA. PLoS Pathog 2020; 16:e1009147. [PMID: 33351861 PMCID: PMC7787678 DOI: 10.1371/journal.ppat.1009147] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 01/06/2021] [Accepted: 11/12/2020] [Indexed: 12/20/2022] Open
Abstract
The central function of the retroviral integrase protein (IN) is to catalyze the integration of viral DNA into the host genome to form the provirus. The IN protein has also been reported to play a role in a number of other processes throughout the retroviral life cycle such as reverse transcription, nuclear import and particle morphogenesis. Studies have shown that HIV-1 IN is subject to multiple post-translational modifications (PTMs) including acetylation, phosphorylation and SUMOylation. However, the importance of these modifications during infection has been contentious. In this study we attempt to clarify the role of acetylation of HIV-1 IN during the retroviral life cycle. We show that conservative mutation of the known acetylated lysine residues has only a modest effect on reverse transcription and proviral integration efficiency in vivo. However, we observe a large defect in successful expression of proviral genes at early times after infection by an acetylation-deficient IN mutant that cannot be explained by delayed integration dynamics. We demonstrate that the difference between the expression of proviruses integrated by an acetylation mutant and WT IN is likely not due to altered integration site distribution but rather directly due to a lower rate of transcription. Further, the effect of the IN mutation on proviral gene expression is independent of the Tat protein or the LTR promoter. At early times after integration when the transcription defect is observed, the LTRs of proviruses integrated by the mutant IN have altered histone modifications as well as reduced IN protein occupancy. Over time as the transcription defect in the mutant virus diminishes, histone modifications on the WT and mutant proviral LTRs reach comparable levels. These results highlight an unexpected role for the IN protein in regulating proviral transcription at early times post-integration. A key step of the retrovirus life cycle is the insertion of the viral DNA genome into the host cell genome, a process called integration. The process of integration is solely catalyzed by the virally encoded integrase (IN) protein. IN has been reported to influence a number of other viral processes such as reverse transcription, nuclear import and particle morphogenesis. The HIV-1 IN protein is known to be heavily post-translationally modified. In light of the known effect of post-translational modifications on the function of the orthologous proteins of certain retrotransposons, we were motivated to ask how post-translational modifications of HIV-1 IN may regulate its various functions. In this study, we examined the consequences of mutations preventing the acetylation of the IN protein on the retroviral life cycle. Surprisingly, we saw that mutations blocking IN acetylation had only modest effects on viral DNA integration. Instead, we uncovered a novel function for HIV-1 IN in regulating proviral transcription at early times after infection. Our data suggests that IN may be retained on proviral DNA at early times after integration and promote proviral gene expression by altering chromatin modifications at the viral transcriptional promoter.
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Affiliation(s)
- Shelby Winans
- Columbia University, Department of Biochemistry and Molecular Biophysics, New York, New York, United States of America
- Columbia University, Department of Microbiology and Immunology, New York, New York, United States of America
- Howard Hughes Medical Institute, Columbia University, New York, New York United States of America
| | - Stephen P. Goff
- Columbia University, Department of Biochemistry and Molecular Biophysics, New York, New York, United States of America
- Columbia University, Department of Microbiology and Immunology, New York, New York, United States of America
- Howard Hughes Medical Institute, Columbia University, New York, New York United States of America
- * E-mail:
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NKNK: a New Essential Motif in the C-Terminal Domain of HIV-1 Group M Integrases. J Virol 2020; 94:JVI.01035-20. [PMID: 32727879 DOI: 10.1128/jvi.01035-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 07/17/2020] [Indexed: 11/20/2022] Open
Abstract
Using coevolution network interference based on comparison of two phylogenetically distantly related isolates, one from the main group M and the other from the minor group O of HIV-1, we identify, in the C-terminal domain (CTD) of integrase, a new functional motif constituted by four noncontiguous amino acids (N222K240N254K273). Mutating the lysines abolishes integration through decreased 3' processing and inefficient nuclear import of reverse-transcribed genomes. Solution of the crystal structures of wild-type (wt) and mutated CTDs shows that the motif generates a positive surface potential that is important for integration. The number of charges in the motif appears more crucial than their position within the motif. Indeed, the positions of the K's could be permutated or additional K's could be inserted in the motif, generally without affecting integration per se Despite this potential genetic flexibility, the NKNK arrangement is strictly conserved in natural sequences, indicative of an effective purifying selection exerted at steps other than integration. Accordingly, reverse transcription was reduced even in the mutants that retained wt integration levels, indicating that specifically the wt sequence is optimal for carrying out the multiple functions that integrase exerts. We propose that the existence of several amino acid arrangements within the motif, with comparable efficiencies of integration per se, might have constituted an asset for the acquisition of additional functions during viral evolution.IMPORTANCE Intensive studies of HIV-1 have revealed its extraordinary ability to adapt to environmental and immunological challenges, an ability that is also at the basis of antiviral treatment escape. Here, by deconvoluting the different roles of the viral integrase in the various steps of the infectious cycle, we report how the existence of alternative equally efficient structural arrangements for carrying out one function opens up the possibility of adapting to the optimization of further functionalities exerted by the same protein. Such a property provides an asset to increase the efficiency of the infectious process. On the other hand, though, the identification of this new motif provides a potential target for interfering simultaneously with multiple functions of the protein.
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Larguet F, Caté C, Barbeau B, Rassart E, Edouard E. Histone deacetylase 1 interacts with HIV-1 Integrase and modulates viral replication. Virol J 2019; 16:138. [PMID: 31744547 PMCID: PMC6862858 DOI: 10.1186/s12985-019-1249-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 11/05/2019] [Indexed: 01/09/2023] Open
Abstract
Background HIV-1 hijacks the cellular machinery for its own replication through protein-protein interactions between viral and host cell factors. One strategy against HIV-1 infection is thus to target these key protein complexes. As the integration of reverse transcribed viral cDNA into a host cell chromosome is an essential step in the HIV-1 life cycle, catalyzed by the viral integrase and other important host factors, we aimed at identifying new integrase binding partners through a novel approach. Methods A LTR-derived biotinylated DNA fragment complexed with the integrase on magnetic beads was incubated with extracts from integrase-expressing 293 T cells. Liquid chromatography-mass spectrometry/mass spectrometry and co-immunoprecipitation/pull-down experiments were used for the identification of binding partners. Transfections of histone deacetylase 1 (HDAC1) expression vectors and/or specific siRNA were conducted in HeLa-CD4 and 293 T cells followed by infection with fully infectious NL4–3 and luciferase-expressing pseudotyped viruses or by proviral DNA transfection. Fully infectious and pseudotyped viruses produced from HDAC1-silenced 293 T cells were tested for their infectivity toward HeLa-CD4 cells, T cell lines and primary CD4+ T cells. Late RT species and integrated viral DNA were quantified by qPCR and infectivity was measured by luciferase activity and p24 ELISA assay. Results were analyzed by the Student’s t-test. Results Using our integrase-LTR bait approach, we successfully identified new potential integrase-binding partners, including HDAC1. We further confirmed that HDAC1 interacted with the HIV-1 integrase in co-immunoprecipitation and pull-down experiments. HDAC1 knockdown in infected HeLa cells was shown to interfere with an early preintegration step of the HIV-1 replication cycle, which possibly involves reverse transcription. We also observed that, while HDAC1 overexpression inhibited HIV-1 expression after integration, HDAC1 knockdown had no effect on this step. In virus producer cells, HDAC1 knockdown had a limited impact on virus infectivity in either cell lines or primary CD4+ T cells. Conclusions Our results show that HDAC1 interacts with the HIV-1 integrase and affects virus replication before and after integration. Overall, HDAC1 appears to facilitate HIV-1 replication with a major effect on a preintegration step, which likely occurs at the reverse transcription step.
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Affiliation(s)
- Fadila Larguet
- Département des sciences biologiques, and Centre de recherche BioMed, Université du Québec à Montréal, Montréal, QC, Canada
| | - Clément Caté
- Département des sciences biologiques, and Centre de recherche BioMed, Université du Québec à Montréal, Montréal, QC, Canada
| | - Benoit Barbeau
- Département des sciences biologiques, and Centre de recherche BioMed, Université du Québec à Montréal, Montréal, QC, Canada
| | - Eric Rassart
- Département des sciences biologiques, and Centre de recherche BioMed, Université du Québec à Montréal, Montréal, QC, Canada.
| | - Elsy Edouard
- Département des sciences biologiques, and Centre de recherche BioMed, Université du Québec à Montréal, Montréal, QC, Canada.
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Colomer-Lluch M, Castro-Gonzalez S, Serra-Moreno R. Ubiquitination and SUMOylation in HIV Infection: Friends and Foes. Curr Issues Mol Biol 2019; 35:159-194. [PMID: 31422939 DOI: 10.21775/cimb.035.159] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
As intracellular parasites, viruses hijack the cellular machinery to facilitate their replication and spread. This includes favouring the expression of their viral genes over host genes, appropriation of cellular molecules, and manipulation of signalling pathways, including the post-translational machinery. HIV, the causative agent of AIDS, is notorious for using post-translational modifications to generate infectious particles. Here, we discuss the mechanisms by which HIV usurps the ubiquitin and SUMO pathways to modify both viral and host factors to achieve a productive infection, and also how the host innate sensing system uses these post-translational modifications to hinder HIV replication.
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Affiliation(s)
- Marta Colomer-Lluch
- IrsiCaixa AIDS Research Institute, Hospital Germans Trias i Pujol, Badalona, Spain
| | - Sergio Castro-Gonzalez
- Department of Biological Sciences, College of Arts and Sciences, Texas Tech University, Lubbock, TX, USA
| | - Ruth Serra-Moreno
- Department of Biological Sciences, College of Arts and Sciences, Texas Tech University, Lubbock, TX, USA
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9
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Chen L, Keppler OT, Schölz C. Post-translational Modification-Based Regulation of HIV Replication. Front Microbiol 2018; 9:2131. [PMID: 30254620 PMCID: PMC6141784 DOI: 10.3389/fmicb.2018.02131] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/20/2018] [Indexed: 12/13/2022] Open
Abstract
Human immunodeficiency virus (HIV) relies heavily on the host cellular machinery for production of viral progeny. To exploit cellular proteins for replication and to overcome host factors with antiviral activity, HIV has evolved a set of regulatory and accessory proteins to shape an optimized environment for its replication and to facilitate evasion from the immune system. Several cellular pathways are hijacked by the virus to modulate critical steps during the viral life cycle. Thereby, post-translational modifications (PTMs) of viral and cellular proteins gain increasingly attention as modifying enzymes regulate virtually every step of the viral replication cycle. This review summarizes the current knowledge of HIV-host interactions influenced by PTMs with a special focus on acetylation, ubiquitination, and phosphorylation of proteins linked to cellular signaling and viral replication. Insights into these interactions are surmised to aid development of new intervention strategies.
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Affiliation(s)
- Lin Chen
- Max von Pettenkofer-Institute and Gene Center, Virology, National Reference Center for Retroviruses, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Oliver T Keppler
- Max von Pettenkofer-Institute and Gene Center, Virology, National Reference Center for Retroviruses, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Christian Schölz
- Max von Pettenkofer-Institute and Gene Center, Virology, National Reference Center for Retroviruses, Faculty of Medicine, Ludwig-Maximilians-University Munich, Munich, Germany
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Abstract
The HIV genome encodes a small number of viral proteins (i.e., 16), invariably establishing cooperative associations among HIV proteins and between HIV and host proteins, to invade host cells and hijack their internal machineries. As a known example, the HIV envelope glycoprotein GP120 is closely associated with GP41 for viral entry. From a genome-wide perspective, a hypothesis can be worked out to determine whether 16 HIV proteins could develop 120 possible pairwise associations either by physical interactions or by functional associations mediated via HIV or host molecules. Here, we present the first systematic review of experimental evidence on HIV genome-wide protein associations using a large body of publications accumulated over the past 3 decades. Of 120 possible pairwise associations between 16 HIV proteins, at least 34 physical interactions and 17 functional associations have been identified. To achieve efficient viral replication and infection, HIV protein associations play essential roles (e.g., cleavage, inhibition, and activation) during the HIV life cycle. In either a dispensable or an indispensable manner, each HIV protein collaborates with another viral protein to accomplish specific activities that precisely take place at the proper stages of the HIV life cycle. In addition, HIV genome-wide protein associations have an impact on anti-HIV inhibitors due to the extensive cross talk between drug-inhibited proteins and other HIV proteins. Overall, this study presents for the first time a comprehensive overview of HIV genome-wide protein associations, highlighting meticulous collaborations between all viral proteins during the HIV life cycle.
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Affiliation(s)
- Guangdi Li
- Department of Metabolism and Endocrinology, Metabolic Syndrome Research Center, Key Laboratory of Diabetes Immunology, Ministry of Education, National Clinical Research Center for Metabolic Diseases, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China KU Leuven-University of Leuven, Rega Institute for Medical Research, Department of Microbiology and Immunology, Leuven, Belgium
| | - Erik De Clercq
- KU Leuven-University of Leuven, Rega Institute for Medical Research, Department of Microbiology and Immunology, Leuven, Belgium
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11
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Luo Y, Jacobs EY, Greco TM, Mohammed KD, Tong T, Keegan S, Binley JM, Cristea IM, Fenyö D, Rout MP, Chait BT, Muesing MA. HIV-host interactome revealed directly from infected cells. Nat Microbiol 2016; 1:16068. [PMID: 27375898 PMCID: PMC4928716 DOI: 10.1038/nmicrobiol.2016.68] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 04/16/2016] [Indexed: 01/27/2023]
Abstract
Although genetically compact, HIV-1 commandeers vast arrays of cellular machinery to sustain and protect it during cycles of viral outgrowth. Transposon-mediated saturation linker scanning mutagenesis was used to isolate fully replication-competent viruses harbouring a potent foreign epitope tag. Using these viral isolates, we performed differential isotopic labelling and affinity-capture mass spectrometric analyses on samples obtained from cultures of human lymphocytes to classify the vicinal interactomes of the viral Env and Vif proteins as they occur during natural infection. Importantly, interacting proteins were recovered without bias, regardless of their potential for positive, negative or neutral impact on viral replication. We identified specific host associations made with trimerized Env during its biosynthesis, at virological synapses, with innate immune effectors (such as HLA-E) and with certain cellular signalling pathways (for example, Notch1). We also defined Vif associations with host proteins involved in the control of nuclear transcription and nucleoside biosynthesis as well as those interacting stably or transiently with the cytoplasmic protein degradation apparatus. Our approach is broadly applicable to elucidating pathogen-host interactomes, providing high-certainty identification of interactors by their direct access during cycling infection. Understanding the pathophysiological consequences of these associations is likely to provide strategic targets for antiviral intervention.
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Affiliation(s)
- Yang Luo
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
| | - Erica Y. Jacobs
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Todd M. Greco
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08540, USA
| | - Kevin D. Mohammed
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
| | - Tommy Tong
- San Diego Biomedical Research Institute, 10865 Road to the Cure, San Diego, California 92121, USA
| | - Sarah Keegan
- Department of Biochemistry, New York University Langone Medical Center, 227 East 30th Street, New York, New York 10016, USA
| | - James M. Binley
- San Diego Biomedical Research Institute, 10865 Road to the Cure, San Diego, California 92121, USA
| | - Ileana M. Cristea
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Princeton, New Jersey 08540, USA
| | - David Fenyö
- Department of Biochemistry, New York University Langone Medical Center, 227 East 30th Street, New York, New York 10016, USA
| | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Brian T. Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, 1230 York Avenue, New York, New York 10065, USA
| | - Mark A. Muesing
- Aaron Diamond AIDS Research Center, 455 1st Avenue, New York, New York 10016, USA
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12
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HIV Genome-Wide Protein Associations: a Review of 30 Years of Research. Microbiol Mol Biol Rev 2016; 80:679-731. [PMID: 27357278 DOI: 10.1128/mmbr.00065-15] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The HIV genome encodes a small number of viral proteins (i.e., 16), invariably establishing cooperative associations among HIV proteins and between HIV and host proteins, to invade host cells and hijack their internal machineries. As a known example, the HIV envelope glycoprotein GP120 is closely associated with GP41 for viral entry. From a genome-wide perspective, a hypothesis can be worked out to determine whether 16 HIV proteins could develop 120 possible pairwise associations either by physical interactions or by functional associations mediated via HIV or host molecules. Here, we present the first systematic review of experimental evidence on HIV genome-wide protein associations using a large body of publications accumulated over the past 3 decades. Of 120 possible pairwise associations between 16 HIV proteins, at least 34 physical interactions and 17 functional associations have been identified. To achieve efficient viral replication and infection, HIV protein associations play essential roles (e.g., cleavage, inhibition, and activation) during the HIV life cycle. In either a dispensable or an indispensable manner, each HIV protein collaborates with another viral protein to accomplish specific activities that precisely take place at the proper stages of the HIV life cycle. In addition, HIV genome-wide protein associations have an impact on anti-HIV inhibitors due to the extensive cross talk between drug-inhibited proteins and other HIV proteins. Overall, this study presents for the first time a comprehensive overview of HIV genome-wide protein associations, highlighting meticulous collaborations between all viral proteins during the HIV life cycle.
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13
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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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14
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Rowles DL, Tsai YC, Greco TM, Lin AE, Li M, Yeh J, Cristea IM. DNA methyltransferase DNMT3A associates with viral proteins and impacts HSV-1 infection. Proteomics 2015; 15:1968-82. [PMID: 25758154 DOI: 10.1002/pmic.201500035] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 02/17/2015] [Accepted: 03/07/2015] [Indexed: 01/21/2023]
Abstract
Viral infections can alter the cellular epigenetic landscape, through modulation of either DNA methylation profiles or chromatin remodeling enzymes and histone modifications. These changes can act to promote viral replication or host defense. Herpes simplex virus type 1 (HSV-1) is a prominent human pathogen, which relies on interactions with host factors for efficient replication and spread. Nevertheless, the knowledge regarding its modulation of epigenetic factors remains limited. Here, we used fluorescently-labeled viruses in conjunction with immunoaffinity purification and MS to study virus-virus and virus-host protein interactions during HSV-1 infection in primary human fibroblasts. We identified interactions among viral capsid and tegument proteins, detecting phosphorylation of the capsid protein VP26 at sites within its UL37-binding domain, and an acetylation within the major capsid protein VP5. Interestingly, we found a nuclear association between viral capsid proteins and the de novo DNA methyltransferase DNA (cytosine-5)-methyltransferase 3A (DNMT3A), which we confirmed by reciprocal isolations and microscopy. We show that drug-induced inhibition of DNA methyltransferase activity, as well as siRNA- and shRNA-mediated DNMT3A knockdowns trigger reductions in virus titers. Altogether, our results highlight a functional association of viral proteins with the mammalian DNA methyltransferase machinery, pointing to DNMT3A as a host factor required for effective HSV-1 infection.
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Affiliation(s)
- Daniell L Rowles
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Yuan-Chin Tsai
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Todd M Greco
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Aaron E Lin
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Minghao Li
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Justin Yeh
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
| | - Ileana M Cristea
- Lewis Thomas Laboratory, Department of Molecular Biology, Princeton University, Princeton, NJ, USA
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15
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Abstract
HIV integrase (IN) catalyzes the insertion into the genome of the infected human cell of viral DNA produced by the retrotranscription process. The discovery of raltegravir validated the existence of the IN, which is a new target in the field of anti-HIV drug research. The mechanism of catalysis of IN is depicted, and the characteristics of the inhibitors of the catalytic site of this viral enzyme are reported. The role played by the resistance is elucidated, as well as the possibility of bypassing this problem. New approaches to block the integration process are depicted as future perspectives, such as development of allosteric IN inhibitors, dual inhibitors targeting both IN and other enzymes, inhibitors of enzymes that activate IN, activators of IN activity, as well as a gene therapy approach.
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Affiliation(s)
- Roberto Di Santo
- Dipartimento
di Chimica e
Tecnologie del Farmaco, Istituto Pasteur, Fondazione Cenci Bolognetti, “Sapienza” Università di Roma, P.le Aldo Moro 5, I-00185 Rome, Italy
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16
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Abstract
HIV integrase (IN) catalyzes the insertion into the genome of the infected human cell of viral DNA produced by the retrotranscription process. The discovery of raltegravir validated the existence of the IN, which is a new target in the field of anti-HIV drug research. The mechanism of catalysis of IN is depicted, and the characteristics of the inhibitors of the catalytic site of this viral enzyme are reported. The role played by the resistance is elucidated, as well as the possibility of bypassing this problem. New approaches to block the integration process are depicted as future perspectives, such as development of allosteric IN inhibitors, dual inhibitors targeting both IN and other enzymes, inhibitors of enzymes that activate IN, activators of IN activity, as well as a gene therapy approach.
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Affiliation(s)
- Roberto Di Santo
- Dipartimento di Chimica e Tecnologie del Farmaco, Istituto Pasteur, Fondazione Cenci Bolognetti, "Sapienza" Università di Roma , P.le Aldo Moro 5, I-00185 Rome, Italy
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17
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Posttranslational modifications of HIV-1 integrase by various cellular proteins during viral replication. Viruses 2013; 5:1787-801. [PMID: 23863879 PMCID: PMC3738961 DOI: 10.3390/v5071787] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 07/08/2013] [Accepted: 07/09/2013] [Indexed: 12/21/2022] Open
Abstract
HIV-1 integrase (IN) is a key viral enzyme during HIV-1 replication that catalyzes the insertion of viral DNA into the host genome. Recent studies have provided important insights into the multiple posttranslational modifications (PTMs) of IN (e.g., ubiquitination, SUMOylation, acetylation and phosphorylation), which regulate its multifaceted functions. A number of host cellular proteins, including Lens Epithelium‑derived Growth factor (LEDGF/p75), p300 and Ku70 have been shown to interact with IN and be involved in the PTM process of IN, either facilitating or counteracting the IN PTMs. Although previous studies have revealed much about the important roles of IN PTMs, how IN functions are fine-tuned by these PTMs under the physiological setting still needs to be determined. Here, we review the advances in the understanding of the mechanisms and roles of multiple IN PTMs.
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18
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Fletcher AJ, Towers GJ. Inhibition of retroviral replication by members of the TRIM protein family. Curr Top Microbiol Immunol 2013; 371:29-66. [PMID: 23686231 DOI: 10.1007/978-3-642-37765-5_2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The TRIM protein family is emerging as a central component of mammalian antiviral innate immunity. Beginning with the identification of TRIM5α as a mammalian post-entry restriction factor against retroviruses, to the repeated observation that many TRIMs ubiquitinate and regulate signaling pathways, the past decade has witnessed an intense research effort to understand how TRIM proteins influence immunity. The list of viral families targeted directly or indirectly by TRIM proteins has grown to include adenoviruses, hepadnaviruses, picornaviruses, flaviviruses, orthomyxoviruses, paramyxoviruses, herpesviruses, rhabdoviruses and arenaviruses. We have come to appreciate how, through intense bouts of positive selection, some TRIM genes have been honed into species-specific restriction factors. Similarly, in the case of TRIMCyp, we are beginning to understand how viruses too have mutated to evade restriction, suggesting that TRIM and viruses have coevolved for millions of years of primate evolution. Recently, TRIM5α returned to the limelight when it was shown to trigger the expression of antiviral genes upon recognition of an incoming virus, a paradigm shift that demonstrated that restriction factors make excellent pathogen sensors. However, it remains unclear how many of ~100 human TRIM genes are antiviral, despite the expression of many of these genes being upregulated by interferon and upon viral infection. TRIM proteins do not conform to one type of antiviral mechanism, reflecting the diversity of viruses they target. Moreover, the cofactors of restriction remain largely enigmatic. The control of retroviral replication remains an important medical subject and provides a useful backdrop for reviewing how TRIM proteins act to repress viral replication.
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Affiliation(s)
- Adam J Fletcher
- MRC Centre for Medical Molecular Virology, University College, London, UK.
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19
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Ahmad N. Molecular mechanisms of HIV-1 infection in neonatal target cells. Future Virol 2012. [DOI: 10.2217/fvl.12.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
HIV-1-infected neonates and infants have a higher viral load and progress to symptomatic AIDS more rapidly than their own infected mothers, as well as other infected adults, with differences in clinical manifestations, recurrent bacterial infections and CNS disorders. Two major reasons have been attributed to this differential HIV pathogenesis and disease; the relative immaturity of the neonate’s immune system and it’s inability to contain the highly replicating and mutating HIV-1, and the more efficient replication of HIV-1 in neonatal cells than in adult target cells. In this context, it has been demonstrated that HIV-1 replicates more efficiently in neonatal (cord) blood monocytes/macrophages and T lymphocytes – including naive and memory T lymphocytes – compared with adult blood cells. We have also determined the mechanisms of the differential HIV-1 replication in cord versus adult blood monocytes/macrophages and T lymphocytes (naive and memory), finding that it was influenced at the level of HIV-1 gene expression. The increased HIV-1 gene expression in neonatal versus adult target cells was regulated by differential expression of host factors, transcription factors (NF-κB, E2F, HAT-1, TFIIE, Cdk9 and Cyclin T1), signal transducers (STAT3 and STAT5A) and cytokines (IL-1β, IL-6 and IL-10). We also showed that nuclear extracts from cord cells interacted with HIV-1 long terminal repeat cis-acting sequences, including NF-κB, NFAT, AP1 and NF-IL6, to a greater extent when compared with adult peripheral blood mononuclear cell nuclear extracts. Additionally, shRNA of retroviral origin for STAT3 and IL-6 downregulated both their own gene expression as well as that of HIV-1, indicating that these factors influenced the differential expression of HIV-1 genes in cord cells compared with adult cells. In addition, HIV-1 integration plays an important role in differential HIV-1 replication and gene expression in neonatal versus adult cells by integrating into more actively transcribed genes in neonates compared with adults. We characterized 468 HIV-1 integration sites within cord and adult blood T lymphocytes and monocytes/macrophages, including genes coding for cellular components, and those involved with maintenance of the intracellular environment, enzyme regulation, cellular metabolism, catalytic activity and cation transport, as well as several potential transcription factor binding sites at the sites of integration. Additionally, the genes at the integration sites, transcription factors and transcription binding sites were expressed at higher levels in cord than adult target cells. In summary, the increased HIV-1 gene expression and replication in neonatal target cells due to differential expression of host factors all contribute to an increased viral load and faster disease progression in neonates and infants when compared with similar situations in adult patients. Based on these findings, it may be possible to identify new viral and host targets for use in developing strategies for the treatment and prevention of HIV-1.
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Affiliation(s)
- Nafees Ahmad
- Department of Immunobiology, College of Medicine University of Arizona, Tucson, AZ 85724, USA
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20
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Schneider WM, Wu DT, Amin V, Aiyer S, Roth MJ. MuLV IN mutants responsive to HDAC inhibitors enhance transcription from unintegrated retroviral DNA. Virology 2012; 426:188-96. [PMID: 22365328 DOI: 10.1016/j.virol.2012.01.034] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 11/12/2011] [Accepted: 01/27/2012] [Indexed: 12/16/2022]
Abstract
For Moloney murine leukemia virus (M-MuLV), sustained viral infections require expression from an integrated provirus. For many applications, non-integrating retroviral vectors have been utilized to avoid the unwanted effects of integration, however, the level of expression from unintegrated DNA is significantly less than that of integrated provirus. We find that unintegrated DNA expression can be increased in the presence of HDAC inhibitors, such as TSA, when applied in combination with integrase (IN) mutations. These mutants include an active site mutation as well as catalytically active INs bearing mutations of K376 in the MuLV C-terminal domain of IN. MuLV IN K376 is homologous to K266 in HIV-1 IN, a known substrate for acetylation. The MuLV IN protein is acetylated by p300 in vitro, however, the effect of HDAC inhibitors on gene expression from unintegrated DNA is not dependent on the acetylation state of MuLV IN K376.
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Affiliation(s)
- William M Schneider
- University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
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21
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Allouch A, Di Primio C, Alpi E, Lusic M, Arosio D, Giacca M, Cereseto A. The TRIM family protein KAP1 inhibits HIV-1 integration. Cell Host Microbe 2011; 9:484-95. [PMID: 21669397 DOI: 10.1016/j.chom.2011.05.004] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 03/30/2011] [Accepted: 05/13/2011] [Indexed: 01/05/2023]
Abstract
The integration of viral cDNA into the host genome is a critical step in the life cycle of HIV-1. This step is catalyzed by integrase (IN), a viral enzyme that is positively regulated by acetylation via the cellular histone acetyl transferase (HAT) p300. To investigate the relevance of IN acetylation, we searched for cellular proteins that selectively bind acetylated IN and identified KAP1, a protein belonging to the TRIM family of antiviral proteins. KAP1 binds acetylated IN and induces its deacetylation through the formation of a protein complex which includes the deacetylase HDAC1. Modulation of intracellular KAP1 levels in different cell types including T cells, the primary HIV-1 target, revealed that KAP1 curtails viral infectivity by selectively affecting HIV-1 integration. This study identifies KAP1 as a cellular factor restricting HIV-1 infection and underscores the relevance of IN acetylation as a crucial step in the viral infectious cycle.
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Affiliation(s)
- Awatef Allouch
- Molecular Biology Laboratory, Scuola Normale Superiore, Piazza dei Cavalieri 7, Pisa 56126, Italy
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22
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Abstract
Integration is a key step in the HIV-1 life cycle in which the ends of linear viral DNA are covalently joined with host chromosomal DNA. Integrase is the highly conserved and essential viral protein that performs two catalytically related reactions that ultimately lead to the insertion of the viral genome into that of the host cell. The only chemotherapeutic agents against integrase currently available for HIV-1 infected individuals are those that interrupt strand transfer, the second step of catalysis. Accordingly, this article outlines possible future strategies targeting the first catalytic step, 3' processing, as well as other nonenzymatic, yet indispensible, functions thought to be co-ordinated by integrase. Importantly, the interruption of irremediable recombination between viral and host DNAs represents the last step after viral entry at which an otherwise irreversible infection can be prevented.
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23
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Zamborlini A, Coiffic A, Beauclair G, Delelis O, Paris J, Koh Y, Magne F, Giron ML, Tobaly-Tapiero J, Deprez E, Emiliani S, Engelman A, de Thé H, Saïb A. Impairment of human immunodeficiency virus type-1 integrase SUMOylation correlates with an early replication defect. J Biol Chem 2011; 286:21013-22. [PMID: 21454548 PMCID: PMC3121452 DOI: 10.1074/jbc.m110.189274] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 02/23/2011] [Indexed: 11/06/2022] Open
Abstract
HIV-1 integrase (IN) orchestrates the integration of the reverse transcribed viral cDNA into the host cell genome and participates also in other steps of HIV-1 replication. Cellular and viral factors assist IN in performing its multiple functions, and post-translational modifications contribute to modulate its activities. Here, we show that HIV-1 IN is modified by SUMO proteins and that phylogenetically conserved SUMOylation consensus motifs represent major SUMO acceptor sites. Viruses harboring SUMOylation site IN mutants displayed a replication defect that was mapped during the early stages of infection, before integration but after reverse transcription. Because SUMOylation-defective IN mutants retained WT catalytic activity, we hypothesize that SUMOylation might regulate the affinity of IN for co-factors, contributing to efficient HIV-1 replication.
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Affiliation(s)
- Alessia Zamborlini
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
- the Conservatoire des Arts et Métiers, Paris, France
| | - Audrey Coiffic
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Guillaume Beauclair
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Olivier Delelis
- Laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée, CNRS UMR8113, Ecole Normale Supérieure, 94235 Cachan, France
| | - Joris Paris
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Yashuiro Koh
- the Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, Massachusetts 02215
| | - Fabian Magne
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
- the Conservatoire des Arts et Métiers, Paris, France
| | - Marie-Lou Giron
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Joelle Tobaly-Tapiero
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Eric Deprez
- Laboratoire de Biotechnologies et Pharmacologie Génétique Appliquée, CNRS UMR8113, Ecole Normale Supérieure, 94235 Cachan, France
| | - Stephane Emiliani
- INSERM U1016, CNRS UMR8104, Université Paris Descartes, Institut Cochin, 75014 Paris, France, and
| | - Alan Engelman
- the Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, Massachusetts 02215
| | - Hugues de Thé
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
| | - Ali Saïb
- From the CNRS UMR7212, INSERM U944, Institut Universitaire d'Hématologie-Université Paris7 Diderot, 75475 Paris, France
- the Conservatoire des Arts et Métiers, Paris, France
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24
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HIVToolbox, an integrated web application for investigating HIV. PLoS One 2011; 6:e20122. [PMID: 21647445 PMCID: PMC3102074 DOI: 10.1371/journal.pone.0020122] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 04/12/2011] [Indexed: 11/19/2022] Open
Abstract
Many bioinformatic databases and applications focus on a limited domain of knowledge federating links to information in other databases. This segregated data structure likely limits our ability to investigate and understand complex biological systems. To facilitate research, therefore, we have built HIVToolbox, which integrates much of the knowledge about HIV proteins and allows virologists and structural biologists to access sequence, structure, and functional relationships in an intuitive web application. HIV-1 integrase protein was used as a case study to show the utility of this application. We show how data integration facilitates identification of new questions and hypotheses much more rapid and convenient than current approaches using isolated repositories. Several new hypotheses for integrase were created as an example, and we experimentally confirmed a predicted CK2 phosphorylation site. Weblink: [http://hivtoolbox.bio-toolkit.com].
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25
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Sequential deletion of the integrase (Gag-Pol) carboxyl terminus reveals distinct phenotypic classes of defective HIV-1. J Virol 2011; 85:4654-66. [PMID: 21367893 DOI: 10.1128/jvi.02374-10] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A requisite step in the life cycle of human immunodeficiency virus type 1 (HIV-1) is the insertion of the viral genome into that of the host cell, a process catalyzed by the 288-amino-acid (32-kDa) viral integrase (IN). IN recognizes and cleaves the ends of reverse-transcribed viral DNA and directs its insertion into the chromosomal DNA of the target cell. IN function, however, is not limited to integration, as the protein is required for other aspects of viral replication, including assembly, virion maturation, and reverse transcription. Previous studies demonstrated that IN is comprised of three domains: the N-terminal domain (NTD), catalytic core domain (CCD), and C-terminal domain (CTD). Whereas the CCD is mainly responsible for providing the structural framework for catalysis, the roles of the other two domains remain enigmatic. This study aimed to elucidate the primary and subsidiary roles that the CTD has in protein function. To this end, we generated and tested a nested set of IN C-terminal deletion mutants in measurable assays of virologic function. We discovered that removal of up to 15 residues (IN 273) resulted in incremental diminution of enzymatic function and infectivity and that removal of the next three residues resulted in a loss of infectivity. However, replication competency was surprisingly reestablished with one further truncation, corresponding to IN 269 and coinciding with partial restoration of integration activity, but it was lost permanently for all truncations extending N terminal to this position. Our analyses of these replication-competent and -incompetent truncation mutants suggest potential roles for the IN CTD in precursor protein processing, reverse transcription, integration, and IN multimerization.
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26
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Benkhelifa-Ziyyat S, Bucher S, Zanta-Boussif MA, Pasquet J, Danos O. Changes in the accessibility of the HIV-1 Integrase C-terminus in the presence of cellular proteins. Retrovirology 2010; 7:27. [PMID: 20367881 PMCID: PMC2859751 DOI: 10.1186/1742-4690-7-27] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 04/05/2010] [Indexed: 11/10/2022] Open
Abstract
Background Following entry, uncoating, and reverse transcription, a number of cellular proteins become associated with the Human Immunodeficiency Virus type 1 (HIV-1) pre-integration complex (PIC). With the goal of obtaining reagents for the analysis of the HIV-1 PIC composition and localisation, we have constructed functional integrase (IN) and matrix (MA) proteins that can be biotinylated during virus production and captured using streptavidin-coated beads. Results Although the labelled C-terminus allows for the sensitive detection of virion-associated IN, it becomes inaccessible in the presence of cellular proteins. This masking is not dependent on the nature of the tag and does not occur with the tagged MA. It was not observed either with an IN mutant unable to interact with LEDGF/p75, or when LEDGF/p75 was depleted from cells. Conclusion Our observation suggests that a structural rearrangement or oligomerization of the IN protein occurs during the early steps of infection and that this process is related to the presence of LEDGF/p75.
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27
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GCN5-dependent acetylation of HIV-1 integrase enhances viral integration. Retrovirology 2010; 7:18. [PMID: 20226045 PMCID: PMC2848186 DOI: 10.1186/1742-4690-7-18] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 03/12/2010] [Indexed: 11/24/2022] Open
Abstract
Background An essential event during the replication cycle of HIV-1 is the integration of the reverse transcribed viral DNA into the host cellular genome. Our former report revealed that HIV-1 integrase (IN), the enzyme that catalyzes the integration reaction, is positively regulated by acetylation mediated by the histone acetyltransferase (HAT) p300. Results In this study we demonstrate that another cellular HAT, GCN5, acetylates IN leading to enhanced 3'-end processing and strand transfer activities. GCN5 participates in the integration step of HIV-1 replication cycle as demonstrated by the reduced infectivity, due to inefficient provirus formation, in GCN5 knockdown cells. Within the C-terminal domain of IN, four lysines (K258, K264, K266, and K273) are targeted by GCN5 acetylation, three of which (K264, K266, and K273) are also modified by p300. Replication analysis of HIV-1 clones carrying substitutions at the IN lysines acetylated by both GCN5 and p300, or exclusively by GCN5, demonstrated that these residues are required for efficient viral integration. In addition, a comparative analysis of the replication efficiencies of the IN triple- and quadruple-mutant viruses revealed that even though the lysines targeted by both GCN5 and p300 are required for efficient virus integration, the residue exclusively modified by GCN5 (K258) does not affect this process. Conclusions The results presented here further demonstrate the relevance of IN post-translational modification by acetylation, which results from the catalytic activities of multiple HATs during the viral replication cycle. Finally, this study contributes to clarifying the recent debate raised on the role of IN acetylated lysines during HIV-1 infection.
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28
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Sundaravaradan V, Mehta R, Harris DT, Zack JA, Ahmad N. Differential expression and interaction of host factors augment HIV-1 gene expression in neonatal mononuclear cells. Virology 2010; 400:32-43. [PMID: 20138641 DOI: 10.1016/j.virol.2010.01.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Revised: 06/12/2009] [Accepted: 01/12/2010] [Indexed: 10/19/2022]
Abstract
We have previously shown a higher level of HIV-1 replication and gene expression in neonatal (cord) blood mononuclear cells (CBMC) compared with adult blood cells (PBMC), which could be due to differential expression of host factors. We performed the gene expression profile of CBMC and PBMC and found that 8013 genes were expressed at higher levels in CBMC than PBMC and 8028 genes in PBMC than CBMC, including 1181 and 1414 genes upregulated after HIV-1 infection in CBMC and PBMC, respectively. Several transcription factors (NF-kappaB, E2F, HAT-1, TFIIE, Cdk9, Cyclin T1), signal transducers (STAT3, STAT5A) and cytokines (IL-1beta, IL-6, IL-10) were upregulated in CBMC than PBMC, which are known to influence HIV-1 replication. In addition, a repressor of HIV-1 transcription, YY1, was down regulated in CBMC than PBMC and several matrix metalloproteinase (MMP-7, -12, -14) were significantly upregulated in HIV-1 infected CBMC than PBMC. Furthermore, we show that CBMC nuclear extracts interacted with a higher extent to HIV-1 LTR cis-acting sequences, including NF-kappaB, NFAT, AP1 and NF-IL6 compared with PBMC nuclear extracts and retroviral based short hairpin RNA (shRNA) for STAT3 and IL-6 down regulated their own and HIV-1 gene expression, signifying that these factors influenced differential HIV-1 gene expression in CBMC than PBMC.
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Affiliation(s)
- Vasudha Sundaravaradan
- Department of Immunobiology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA
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29
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Di Fenza A, Rocchia W, Tozzini V. Complexes of HIV-1 integrase with HAT proteins: multiscale models, dynamics, and hypotheses on allosteric sites of inhibition. Proteins 2009; 76:946-58. [PMID: 19306343 DOI: 10.1002/prot.22399] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A new and very promising strategy for HIV drug discovery consists in blocking the multiple functional interactions between HIV-1 integrase (IN) and its cellular cofactors. At present, this line of action is hindered by the absence of three-dimensional structures of IN in complex with any of them. In this article, we developed a full-length three-dimensional structure of IN, including the highly flexible terminal residues 270-288, which are not experimentally solved. Additionally, we built models of IN complexed to the human acetyltransferases GCN5 and p300 based on available structural and mutagenesis data. Then, we studied the dynamical behavior of these models by means of the Coarse-Grained Molecular Dynamics (CGMD) and Essential Dynamics (ED) to locate and characterize the nature of the largest collective motions. We found correlated motions involving distant regions of IN. Moreover, we found that these are influenced by the binding with the acetyltransferases (HATs). Taken together these findings suggest a way to affect the acetyltransferase binding by an allosteric type of inhibition and provide an important new approach for the drug design against HIV disease.
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Affiliation(s)
- Armida Di Fenza
- NEST, Scuola Normale Superiore and CNR-INFM, IIT UdR, Piazza dei Cavalieri 7, I-56126 Pisa, Italy.
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Warren K, Warrilow D, Meredith L, Harrich D. Reverse Transcriptase and Cellular Factors: Regulators of HIV-1 Reverse Transcription. Viruses 2009; 1:873-94. [PMID: 21994574 PMCID: PMC3185528 DOI: 10.3390/v1030873] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 11/06/2009] [Accepted: 11/09/2009] [Indexed: 01/16/2023] Open
Abstract
There is ample evidence that synthesis of HIV-1 proviral DNA from the viral RNA genome during reverse transcription requires host factors. However, only a few cellular proteins have been described in detail that affect reverse transcription and interact with reverse transcriptase (RT). HIV-1 integrase is an RT binding protein and a number of IN-binding proteins including INI1, components of the Sin3a complex, and Gemin2 affect reverse transcription. In addition, recent studies implicate the cellular proteins HuR, AKAP149, and DNA topoisomerase I in reverse transcription through an interaction with RT. In this review we will consider interactions of reverse transcription complex with viral and cellular factors and how they affect the reverse transcription process.
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Affiliation(s)
- Kylie Warren
- Division of Infectious Diseases, Queensland Institute of Medical Research, Brisbane, QLD, Australia; E-Mails: (K.W.); (D.W.); (L.M.)
- School of Natural Sciences, University of Western Sydney, Hawkesbury, NSW, Australia
| | - David Warrilow
- Division of Infectious Diseases, Queensland Institute of Medical Research, Brisbane, QLD, Australia; E-Mails: (K.W.); (D.W.); (L.M.)
| | - Luke Meredith
- Division of Infectious Diseases, Queensland Institute of Medical Research, Brisbane, QLD, Australia; E-Mails: (K.W.); (D.W.); (L.M.)
- Griffith Medical Research College, a joint program of Griffith University and the Queensland Institute of Medical Research, QIMR, Herston, QLD, 4006, Australia
| | - David Harrich
- Division of Infectious Diseases, Queensland Institute of Medical Research, Brisbane, QLD, Australia; E-Mails: (K.W.); (D.W.); (L.M.)
- Griffith Medical Research College, a joint program of Griffith University and the Queensland Institute of Medical Research, QIMR, Herston, QLD, 4006, Australia
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +61-7-3845-36791; Fax: +61-7-3362-0107
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Natural polymorphisms of human immunodeficiency virus type 1 integrase and inherent susceptibilities to a panel of integrase inhibitors. Antimicrob Agents Chemother 2009; 53:4275-82. [PMID: 19651917 DOI: 10.1128/aac.00397-09] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We evaluated the human immunodeficiency virus type 1 (HIV-1) integrase coding region of the pol gene for the presence of natural polymorphisms in patients during early infection (AHI) and with triple-class drug-resistant HIV-1 (MDR). We analyzed selected recombinant viruses containing patient-derived HIV-1 integrase for susceptibility to a panel of strand transfer integrase inhibitors (InSTI). A pretreatment sequence analysis of the integrase coding region was performed for 112 patients identified during acute or early infection and 15 patients with triple-class resistance. A phenotypic analysis was done on 10 recombinant viruses derived from nine patients against a panel of six diverse InSTI. Few of the polymorphisms associated with in vitro InSTI resistance were identified in the samples from newly infected individuals or those patients with MDR HIV-1. We identified polymorphisms V72I, L74I, T97A, V151I, M154I/L, E157Q, V165I, V201I, I203M, T206S, and S230N. V72I was the most common, seen in 63 (56.3%) of the AHI samples. E157Q was the only naturally occurring mutation thought to contribute to resistance to elvitegravir, raltegravir, and L-870,810. None of the patient-derived viruses demonstrated any significant decrease in susceptibility to the drugs tested. In summary, the integrase coding region contains as much natural variation as that seen in protease, but mutations associated with high-level resistance to existing InSTI are rarely, if ever, present in integrase naïve patients, especially those being used clinically. Most of the highly prevalent polymorphisms have little effect on InSTI susceptibility in the absence of specific primary mutations. Baseline testing for integrase susceptibility in InSTI-naïve patients is not currently warranted.
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Recruitment of a SAP18-HDAC1 complex into HIV-1 virions and its requirement for viral replication. PLoS Pathog 2009; 5:e1000463. [PMID: 19503603 PMCID: PMC2685004 DOI: 10.1371/journal.ppat.1000463] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Accepted: 05/04/2009] [Indexed: 02/06/2023] Open
Abstract
HIV-1 integrase (IN) is a virally encoded protein required for integration of viral cDNA into host chromosomes. INI1/hSNF5 is a component of the SWI/SNF complex that interacts with HIV-1 IN, is selectively incorporated into HIV-1 (but not other retroviral) virions, and modulates multiple steps, including particle production and infectivity. To gain further insight into the role of INI1 in HIV-1 replication, we screened for INI1-interacting proteins using the yeast two-hybrid system. We found that SAP18 (Sin3a associated protein 18 kD), a component of the Sin3a-HDAC1 complex, directly binds to INI1 in yeast, in vitro and in vivo. Interestingly, we found that IN also binds to SAP18 in vitro and in vivo. SAP18 and components of a Sin3A-HDAC1 complex were specifically incorporated into HIV-1 (but not SIV and HTLV-1) virions in an HIV-1 IN-dependent manner. Using a fluorescence-based assay, we found that HIV-1 (but not SIV) virion preparations harbour significant deacetylase activity, indicating the specific recruitment of catalytically active HDAC into the virions. To determine the requirement of virion-associated HDAC1 to HIV-1 replication, an inactive, transdominant negative mutant of HDAC1 (HDAC1(H141A)) was utilized. Incorporation of HDAC1(H141A) decreased the virion-associated histone deacetylase activity. Furthermore, incorporation of HDAC1(H141A) decreased the infectivity of HIV-1 (but not SIV) virions. The block in infectivity due to virion-associated HDAC1(H141A) occurred specifically at the early reverse transcription stage, while entry of the virions was unaffected. RNA-interference mediated knock-down of HDAC1 in producer cells resulted in decreased virion-associated HDAC1 activity and a reduction in infectivity of these virions. These studies indicate that HIV-1 IN and INI1/hSNF5 bind SAP18 and selectively recruit components of Sin3a-HDAC1 complex into HIV-1 virions. Furthermore, HIV-1 virion-associated HDAC1 is required for efficient early post-entry events, indicating a novel role for HDAC1 during HIV-1 replication.
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Dietschy T, Shevelev I, Pena-Diaz J, Hühn D, Kuenzle S, Mak R, Miah MF, Hess D, Fey M, Hottiger MO, Janscak P, Stagljar I. p300-mediated acetylation of the Rothmund-Thomson-syndrome gene product RECQL4 regulates its subcellular localization. J Cell Sci 2009; 122:1258-67. [PMID: 19299466 DOI: 10.1242/jcs.037747] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
RECQL4 belongs to the conserved RecQ family of DNA helicases, members of which play important roles in the maintenance of genome stability in all organisms that have been examined. Although genetic alterations in the RECQL4 gene are reported to be associated with three autosomal recessive disorders (Rothmund-Thomson, RAPADILINO and Baller-Gerold syndromes), the molecular role of RECQL4 still remains poorly understood. Here, we show that RECQL4 specifically interacts with the histone acetyltransferase p300 (also known as p300 HAT), both in vivo and in vitro, and that p300 acetylates one or more of the lysine residues at positions 376, 380, 382, 385 and 386 of RECQL4. Furthermore, we report that these five lysine residues lie within a short motif of 30 amino acids that is essential for the nuclear localization of RECQL4. Remarkably, the acetylation of RECQL4 by p300 in vivo leads to a significant shift of a proportion of RECQL4 protein from the nucleus to the cytoplasm. This accumulation of the acetylated RECQL4 is a result of its inability to be imported into the nucleus. Our results provide the first evidence of a post-translational modification of the RECQL4 protein, and suggest that acetylation of RECQL4 by p300 regulates the trafficking of RECQL4 between the nucleus and the cytoplasm.
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Affiliation(s)
- Tobias Dietschy
- Department of Biochemistry, Faculty of Medicine, Terrence Donnelly Centre for Cellular and Biomolecular Research (dCCBR), University of Toronto, Toronto ON, Canada M5S 3E1
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Integrase and integration: biochemical activities of HIV-1 integrase. Retrovirology 2008; 5:114. [PMID: 19091057 PMCID: PMC2615046 DOI: 10.1186/1742-4690-5-114] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 12/17/2008] [Indexed: 01/12/2023] Open
Abstract
Integration of retroviral DNA is an obligatory step of retrovirus replication because proviral DNA is the template for productive infection. Integrase, a retroviral enzyme, catalyses integration. The process of integration can be divided into two sequential reactions. The first one, named 3'-processing, corresponds to a specific endonucleolytic reaction which prepares the viral DNA extremities to be competent for the subsequent covalent insertion, named strand transfer, into the host cell genome by a trans-esterification reaction. Recently, a novel specific activity of the full length integrase was reported, in vitro, by our group for two retroviral integrases (HIV-1 and PFV-1). This activity of internal cleavage occurs at a specific palindromic sequence mimicking the LTR-LTR junction described into the 2-LTR circles which are peculiar viral DNA forms found during viral infection. Moreover, recent studies demonstrated the existence of a weak palindromic consensus found at the integration sites. Taken together, these data underline the propensity of retroviral integrases for binding symmetrical sequences and give perspectives for targeting specific sequences used for gene therapy.
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Abstract
Retroviral replication hinges on the formation of the provirus, the integrated product of the linear DNA that is made during reverse transcription. Integration is catalyzed by the viral recombinase integrase, yet a number of studies indicate that other viral or cellular proteins play important cofactor roles during HIV-1 integration. Some of these factors bind directly to integrase, whereas others gain access to the integration machinery by binding to the DNA or other viral proteins. This article reviews recent advances on the roles of cellular proteins in HIV-1 integration. As a number of studies have highlighted a particularly important role for the integrase interactor lens epithelium-derived growth factor (LEDGF), much of the focus will be on its mechanism of action and the potential to develop inhibitors of this crucial virus–host interaction.
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Affiliation(s)
- Alan Engelman
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute and Division of AIDS, Harvard Medical School, Boston, MA 02115, USA
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Al-Mawsawi LQ, Neamati N. Blocking interactions between HIV-1 integrase and cellular cofactors: an emerging anti-retroviral strategy. Trends Pharmacol Sci 2007; 28:526-35. [PMID: 17888520 DOI: 10.1016/j.tips.2007.09.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2007] [Accepted: 09/07/2007] [Indexed: 12/17/2022]
Abstract
HIV-1 integrase (IN) executes the insertion of proviral DNA into the host cell genome, an essential step in the retroviral life cycle. This is a multi-step process that starts in the cytosol and culminates in the nucleus of the infected cell. It is becoming increasingly clear that IN interacts with a wide range of different host-cell proteins throughout the viral life cycle. These cellular cofactors are exploited for various functions, including nuclear import, DNA target-site selection and virion assembly. The disruption of key interactions between IN and direct cellular cofactors affords a novel therapeutic approach for the design and development of new classes of anti-retroviral agents. Here, we will discuss the rationale behind this emerging and promising therapeutic strategy for HIV drug discovery. Our discussion includes the identified IN cellular cofactors, key research developments in the field and the implications this approach will have on the current HIV treatment regimen.
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Affiliation(s)
- Laith Q Al-Mawsawi
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, California 90089, USA
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Apolonia L, Waddington SN, Fernandes C, Ward NJ, Bouma G, Blundell MP, Thrasher AJ, Collins MK, Philpott NJ. Stable gene transfer to muscle using non-integrating lentiviral vectors. Mol Ther 2007; 15:1947-54. [PMID: 17700544 DOI: 10.1038/sj.mt.6300281] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Human immunodeficiency virus (HIV)-based lentiviral vectors (LVs) hold immense promise for gene delivery applications because of their relatively large packaging capacity and their ability to infect a range of cell types. The genome of HIV non-specifically integrates into the host genome, and this promotes efficient, stable transgene expression in dividing cells. However, integration can also be problematic because of variations in gene expression among cells, possible gene silencing and, most importantly, insertional mutagenesis which can lead to undesirable effects such as malignant transformation. In order to alleviate these problems, we have developed a range of non-integrating LVs (NILVs) by introducing point mutations into the catalytic site, chromosome binding site, and viral DNA binding site of the viral integrase (IN). In addition, we have mutated the IN attachment (att) sites within the HIV long terminal repeats (LTRs). All of the vectors produced show efficient reverse transcription and transgene expression in dividing cells and prolonged expression in non-dividing myotubes. Finally, we show that NILV can be used for achieving highly effective gene transfer and expression in muscle in vivo.
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Affiliation(s)
- Luis Apolonia
- Molecular Immunology Unit, Institute of Child Health, London, UK
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