1
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Sun J, Kessl JJ. Optimizing the Multimerization Properties of Quinoline-Based Allosteric HIV-1 Integrase Inhibitors. Viruses 2024; 16:200. [PMID: 38399977 PMCID: PMC10892445 DOI: 10.3390/v16020200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/25/2024] Open
Abstract
Allosteric HIV-1 Integrase (IN) Inhibitors or ALLINIs bind at the dimer interface of the IN, away from the enzymatic catalytic site, and disable viral replication by inducing over-multimerization of IN. Interestingly, these inhibitors are capable of impacting both the early and late stages of viral replication. To better understand the important binding features of multi-substituted quinoline-based ALLINIs, we have surveyed published studies on IN multimerization and antiviral properties of various substituted quinolines at the 4, 6, 7, and 8 positions. Here we show how the efficacy of these inhibitors can be modulated by the nature of the substitutions at those positions. These features not only improve the overall antiviral potencies of these compounds but also significantly shift the selectivity toward the viral maturation stage. Thus, to fully maximize the potency of ALLINIs, the interactions between the inhibitor and multiple IN subunits need to be simultaneously optimized.
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Affiliation(s)
- Jian Sun
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Jacques J. Kessl
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, MS 39406, USA
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2
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Dinh T, Tber Z, Rey JS, Mengshetti S, Annamalai AS, Haney R, Briganti L, Amblard F, Fuchs JR, Cherepanov P, Kim K, Schinazi RF, Perilla JR, Kim B, Kvaratskhelia M. The structural and mechanistic bases for the viral resistance to allosteric HIV-1 integrase inhibitor pirmitegravir. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.26.577387. [PMID: 38328097 PMCID: PMC10849636 DOI: 10.1101/2024.01.26.577387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are investigational antiretroviral agents which potently impair virion maturation by inducing hyper-multimerization of IN and inhibiting its interaction with viral genomic RNA. The pyrrolopyridine-based ALLINI pirmitegravir (PIR) has recently advanced into Phase 2a clinical trials. Previous cell culture based viral breakthrough assays identified the HIV-1(Y99H/A128T IN) variant that confers substantial resistance to this inhibitor. Here, we have elucidated the unexpected mechanism of viral resistance to PIR. While both Tyr99 and Ala128 are positioned within the inhibitor binding V-shaped cavity at the IN catalytic core domain (CCD) dimer interface, the Y99H/A128T IN mutations did not substantially affect direct binding of PIR to the CCD dimer or functional oligomerization of full-length IN. Instead, the drug-resistant mutations introduced a steric hindrance at the inhibitor mediated interface between CCD and C-terminal domain (CTD) and compromised CTD binding to the CCDY99H/A128T + PIR complex. Consequently, full-length INY99H/A128T was substantially less susceptible to the PIR induced hyper-multimerization than the WT protein, and HIV-1(Y99H/A128T IN) conferred >150-fold resistance to the inhibitor compared to the WT virus. By rationally modifying PIR we have developed its analog EKC110, which readily induced hyper-multimerization of INY99H/A128T in vitro and was ~14-fold more potent against HIV-1(Y99H/A128T IN) than the parent inhibitor. These findings suggest a path for developing improved PIR chemotypes with a higher barrier to resistance for their potential clinical use.
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Affiliation(s)
- Tung Dinh
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Zahira Tber
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Juan S Rey
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Seema Mengshetti
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Arun S Annamalai
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Reed Haney
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lorenzo Briganti
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Franck Amblard
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - James R Fuchs
- College of Pharmacy, The Ohio State University, Columbus, Ohio, United States
| | - Peter Cherepanov
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | | | - Raymond F Schinazi
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Juan R Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Baek Kim
- Center for ViroScience and Cure, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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3
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Loaiza JD, Chvatal-Medina M, Hernandez JC, Rugeles MT. Integrase inhibitors: current protagonists in antiretroviral therapy. Immunotherapy 2023; 15:1477-1495. [PMID: 37822251 DOI: 10.2217/imt-2023-0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Abstract
Since HIV was identified as the etiological agent of AIDS, there have been significant advances in antiretroviral therapy (ART) that has reduced morbidity/mortality. Still, the viral genome's high mutation rate, suboptimal ART regimens, incomplete adherence to therapy and poor control of the viral load generate variants resistant to multiple drugs. Licensing over 30 anti-HIV drugs worldwide, including integrase inhibitors, has marked a milestone since they are potent and well-tolerated drugs. In addition, they favor a faster recovery of CD4+ T cells. They also increase the diversity profile of the gut microbiota and reduce inflammatory markers. All of these highlight the importance of including them in different ART regimens.
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Affiliation(s)
- John D Loaiza
- Grupo Inmunovirología, Facultad de medicina, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Mateo Chvatal-Medina
- Grupo Inmunovirología, Facultad de medicina, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Juan C Hernandez
- Infettare, Facultad de medicina, Universidad Cooperativa de Colombia, Medellín, 050012, Colombia
| | - Maria T Rugeles
- Grupo Inmunovirología, Facultad de medicina, Universidad de Antioquia, Medellín, 050010, Colombia
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4
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Tocco G, Canton S, Laus A, Caboni P, Le Grice SFJ, Tramontano E, Esposito F. Dihydroxyphenyl- and Heteroaromatic-Based Thienopyrimidinones to Tackle HIV-1 LEDGF/p75-Dependent IN Activity. Molecules 2023; 28:6700. [PMID: 37764476 PMCID: PMC10537185 DOI: 10.3390/molecules28186700] [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: 07/20/2023] [Revised: 09/16/2023] [Accepted: 09/17/2023] [Indexed: 09/29/2023] Open
Abstract
The spread of Human Immunodeficiency Virus (HIV) still represents a global public health issue of major concern, and would benefit from unveiling unique viral features as targets for drug design. In this respect, HIV-1 integrase (IN), due to the absence of homologs in human cells, is a popular target for the synthesis of novel selective compounds. Moreover, as drug-resistant viral strains are rapidly evolving, the development of novel allosteric inhibitors is acutely required. Recently, we have observed that Kuwanon-L, quinazolinones and thienopyrimidinones containing at least one polyphenol unit, effectively inhibited HIV-1 IN activity. Thus, in the present research, novel dihydroxyphenyl-based thienopyrimidinone derivatives were investigated for their LEDGF/p75-dependent IN inhibitory activity. Our findings indicated a close correlation between the position of the OH group on the phenyl moiety and IN inhibitory activity of these compounds. As catechol may be involved in cytotoxicity, its replacement by other aromatic scaffolds was also exploited. As a result, compounds 21-23, 25 and 26 with enhanced IN inhibitory activity provided good lead candidates, with 25 being the most selective for IN. Lastly, UV spectrometric experiments suggested a plausible allosteric mode of action, as none of the thienopirimidinones showed Mg2+ chelation properties otherwise typical of IN strand transfer inhibitors (INSTIs).
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Affiliation(s)
- Graziella Tocco
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
| | - Serena Canton
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
| | - Antonio Laus
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
| | - Pierluigi Caboni
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
| | - Stuart F. J. Le Grice
- Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA;
| | - Enzo Tramontano
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
| | - Francesca Esposito
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (S.C.); (A.L.); (P.C.); (E.T.); (F.E.)
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5
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Bonnard D, Le Rouzic E, Singer MR, Yu Z, Le Strat F, Batisse C, Batisse J, Amadori C, Chasset S, Pye VE, Emiliani S, Ledoussal B, Ruff M, Moreau F, Cherepanov P, Benarous R. Biological and Structural Analyses of New Potent Allosteric Inhibitors of HIV-1 Integrase. Antimicrob Agents Chemother 2023; 67:e0046223. [PMID: 37310224 PMCID: PMC10353390 DOI: 10.1128/aac.00462-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 05/08/2023] [Indexed: 06/14/2023] Open
Abstract
HIV-1 integrase-LEDGF allosteric inhibitors (INLAIs) share the binding site on the viral protein with the host factor LEDGF/p75. These small molecules act as molecular glues promoting hyper-multimerization of HIV-1 IN protein to severely perturb maturation of viral particles. Herein, we describe a new series of INLAIs based on a benzene scaffold that display antiviral activity in the single digit nanomolar range. Akin to other compounds of this class, the INLAIs predominantly inhibit the late stages of HIV-1 replication. A series of high-resolution crystal structures revealed how these small molecules engage the catalytic core and the C-terminal domains of HIV-1 IN. No antagonism was observed between our lead INLAI compound BDM-2 and a panel of 16 clinical antiretrovirals. Moreover, we show that compounds retained high antiviral activity against HIV-1 variants resistant to IN strand transfer inhibitors and other classes of antiretroviral drugs. The virologic profile of BDM-2 and the recently completed single ascending dose phase I trial (ClinicalTrials.gov identifier: NCT03634085) warrant further clinical investigation for use in combination with other antiretroviral drugs. Moreover, our results suggest routes for further improvement of this emerging drug class.
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Affiliation(s)
| | | | - Matthew R. Singer
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London, United Kingdom
| | - Zhe Yu
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London, United Kingdom
| | | | - Claire Batisse
- IGBMC, INSERM, CNRS, Université de Strasbourg, Illkirch, France
| | - Julien Batisse
- IGBMC, INSERM, CNRS, Université de Strasbourg, Illkirch, France
| | - Céline Amadori
- Biodim, Romainville, France
- Université Paris Cité, Institut Cochin, INSERM, CNRS, Paris, France
| | | | - Valerie E. Pye
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London, United Kingdom
| | | | | | - Marc Ruff
- IGBMC, INSERM, CNRS, Université de Strasbourg, Illkirch, France
| | | | - Peter Cherepanov
- Chromatin Structure and Mobile DNA Laboratory, Francis Crick Institute, London, United Kingdom
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, United Kingdom
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6
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Eilers G, Gupta K, Allen A, Montermoso S, Murali H, Sharp R, Hwang Y, Bushman FD, Van Duyne G. Structure of a HIV-1 IN-Allosteric inhibitor complex at 2.93 Å resolution: Routes to inhibitor optimization. PLoS Pathog 2023; 19:e1011097. [PMID: 36867659 PMCID: PMC10016701 DOI: 10.1371/journal.ppat.1011097] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 03/15/2023] [Accepted: 01/03/2023] [Indexed: 03/04/2023] Open
Abstract
HIV integrase (IN) inserts viral DNA into the host genome and is the target of the strand transfer inhibitors (STIs), a class of small molecules currently in clinical use. Another potent class of antivirals is the allosteric inhibitors of integrase, or ALLINIs. ALLINIs promote IN aggregation by stabilizing an interaction between the catalytic core domain (CCD) and carboxy-terminal domain (CTD) that undermines viral particle formation in late replication. Ongoing challenges with inhibitor potency, toxicity, and viral resistance motivate research to understand their mechanism. Here, we report a 2.93 Å X-ray crystal structure of the minimal ternary complex between CCD, CTD, and the ALLINI BI-224436. This structure reveals an asymmetric ternary complex with a prominent network of π-mediated interactions that suggest specific avenues for future ALLINI development and optimization.
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Affiliation(s)
- Grant Eilers
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Kushol Gupta
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Audrey Allen
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Saira Montermoso
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Hemma Murali
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Robert Sharp
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Young Hwang
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Frederic D. Bushman
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Gregory Van Duyne
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
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7
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Singer MR, Dinh T, Levintov L, Annamalai AS, Rey JS, Briganti L, Cook NJ, Pye VE, Taylor IA, Kim K, Engelman AN, Kim B, Perilla JR, Kvaratskhelia M, Cherepanov P. The Drug-Induced Interface That Drives HIV-1 Integrase Hypermultimerization and Loss of Function. mBio 2023; 14:e0356022. [PMID: 36744954 PMCID: PMC9973045 DOI: 10.1128/mbio.03560-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 01/03/2023] [Indexed: 02/07/2023] Open
Abstract
Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are an emerging class of small molecules that disrupt viral maturation by inducing the aberrant multimerization of IN. Here, we present cocrystal structures of HIV-1 IN with two potent ALLINIs, namely, BI-D and the drug candidate Pirmitegravir. The structures reveal atomistic details of the ALLINI-induced interface between the HIV-1 IN catalytic core and carboxyl-terminal domains (CCD and CTD). Projecting from their principal binding pocket on the IN CCD dimer, the compounds act as molecular glue by engaging a triad of invariant HIV-1 IN CTD residues, namely, Tyr226, Trp235, and Lys266, to nucleate the CTD-CCD interaction. The drug-induced interface involves the CTD SH3-like fold and extends to the beginning of the IN carboxyl-terminal tail region. We show that mutations of HIV-1 IN CTD residues that participate in the interface with the CCD greatly reduce the IN-aggregation properties of Pirmitegravir. Our results explain the mechanism of the ALLINI-induced condensation of HIV-1 IN and provide a reliable template for the rational development of this series of antiretrovirals through the optimization of their key contacts with the viral target. IMPORTANCE Despite the remarkable success of combination antiretroviral therapy, HIV-1 remains among the major causes of human suffering and loss of life in poor and developing nations. To prevail in this drawn-out battle with the pandemic, it is essential to continue developing advanced antiviral agents to fight drug resistant HIV-1 variants. Allosteric integrase inhibitors (ALLINIs) are an emerging class of HIV-1 antagonists that are orthogonal to the current antiretroviral drugs. These small molecules act as highly specific molecular glue, which triggers the aggregation of HIV-1 integrase. In this work, we present high-resolution crystal structures that reveal the crucial interactions made by two potent ALLINIs, namely, BI-D and Pirmitegravir, with HIV-1 integrase. Our results explain the mechanism of drug action and will inform the development of this promising class of small molecules for future use in antiretroviral regimens.
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Affiliation(s)
- Matthew R. Singer
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Tung Dinh
- Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Lev Levintov
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Arun S. Annamalai
- Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Juan S. Rey
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Lorenzo Briganti
- Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Nicola J. Cook
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Valerie E. Pye
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, United Kingdom
| | | | - Alan N. Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Baek Kim
- Center for Drug Discovery, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, USA
| | - Juan R. Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, USA
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Peter Cherepanov
- Chromatin Structure & Mobile DNA Laboratory, The Francis Crick Institute, London, United Kingdom
- Department of Infectious Disease, St-Mary's Campus, Imperial College London, London, United Kingdom
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Shema Mugisha C, Dinh T, Kumar A, Tenneti K, Eschbach JE, Davis K, Gifford R, Kvaratskhelia M, Kutluay SB. Emergence of Compensatory Mutations Reveals the Importance of Electrostatic Interactions between HIV-1 Integrase and Genomic RNA. mBio 2022; 13:e0043122. [PMID: 35975921 PMCID: PMC9601147 DOI: 10.1128/mbio.00431-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 07/27/2022] [Indexed: 01/11/2023] Open
Abstract
HIV-1 integrase (IN) has a noncatalytic function in virion maturation through its binding to the viral RNA genome (gRNA). Class II IN substitutions inhibit IN-gRNA binding and result in the formation of virions with aberrant morphologies marked by mislocalization of the gRNA between the capsid lattice and the lipid envelope. These viruses are noninfectious due to a block at an early reverse transcription stage in target cells. HIV-1 IN utilizes basic residues within its C-terminal domain (CTD) to bind to the gRNA; however, the molecular nature of how these residues mediate gRNA binding and whether other regions of IN are involved remain unknown. To address this, we have isolated compensatory substitutions in the background of a class II IN mutant virus bearing R269A/K273A substitutions within the IN-CTD. We found that the nearby D256N and D270N compensatory substitutions restored the ability of IN to bind gRNA and led to the formation of mature infectious virions. Reinstating the local positive charge of the IN-CTD through individual D256R, D256K, D278R, and D279R substitutions was sufficient to specifically restore IN-gRNA binding and reverse transcription for the IN R269A/K273A as well as the IN R262A/R263A class II mutants. Structural modeling suggested that compensatory substitutions in the D256 residue created an additional interaction interface for gRNA binding, whereas other substitutions acted locally within the unstructured C-terminal tail of IN. Taken together, our findings highlight the essential role of CTD in gRNA binding and reveal the importance of pliable electrostatic interactions between the IN-CTD and the gRNA. IMPORTANCE In addition to its catalytic function, HIV-1 integrase (IN) binds to the viral RNA genome (gRNA) through positively charged residues (i.e., R262, R263, R269, K273) within its C-terminal domain (CTD) and regulates proper virion maturation. Mutation of these residues results in the formation of morphologically aberrant viruses blocked at an early reverse transcription stage in cells. Here we show that compensatory substitutions in nearby negatively charged aspartic acid residues (i.e., D256N, D270N) restore the ability of IN to bind gRNA for these mutant viruses and result in the formation of accurately matured infectious virions. Similarly, individual charge reversal substitutions at D256 as well as other nearby positions (i.e., D278, D279) are all sufficient to enable the respective IN mutants to bind gRNA, and subsequently restore reverse transcription and virion infectivity. Taken together, our findings reveal the importance of highly pliable electrostatic interactions in IN-gRNA binding.
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Affiliation(s)
- Christian Shema Mugisha
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Tung Dinh
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Abhishek Kumar
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Kasyap Tenneti
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Jenna E. Eschbach
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Keanu Davis
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Robert Gifford
- MRC-University of Glasgow Centre for Virus Research, Bearsden, Glasgow, United Kingdom
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Sebla B. Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, Missouri, USA
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9
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Allosteric Integrase Inhibitor Influences on HIV-1 Integration and Roles of LEDGF/p75 and HDGFL2 Host Factors. Viruses 2022; 14:v14091883. [PMID: 36146690 PMCID: PMC9502684 DOI: 10.3390/v14091883] [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: 07/28/2022] [Revised: 08/11/2022] [Accepted: 08/24/2022] [Indexed: 02/01/2023] Open
Abstract
Allosteric integrase (IN) inhibitors (ALLINIs), which are promising preclinical compounds that engage the lens epithelium-derived growth factor (LEDGF)/p75 binding site on IN, can inhibit different aspects of human immunodeficiency virus 1 (HIV-1) replication. During the late phase of replication, ALLINIs induce aberrant IN hyper-multimerization, the consequences of which disrupt IN binding to genomic RNA and virus particle morphogenesis. During the early phase of infection, ALLINIs can suppress HIV-1 integration into host genes, which is also observed in LEDGF/p75-depelted cells. Despite this similarity, the roles of LEDGF/p75 and its paralog hepatoma-derived growth factor like 2 (HDGFL2) in ALLINI-mediated integration retargeting are untested. Herein, we mapped integration sites in cells knocked out for LEDGF/p75, HDGFL2, or both factors, which revealed that these two proteins in large part account for ALLINI-mediated integration retargeting during the early phase of infection. We also determined that ALLINI-treated viruses are defective during the subsequent round of infection for integration into genes associated with speckle-associated domains, which are naturally highly targeted for HIV-1 integration. Class II IN mutant viruses with alterations distal from the LEDGF/p75 binding site moreover shared this integration retargeting phenotype. Altogether, our findings help to inform the molecular bases and consequences of ALLINI action.
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10
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Donoso M, D’Amico D, Valdebenito S, Hernandez CA, Prideaux B, Eugenin EA. Identification, Quantification, and Characterization of HIV-1 Reservoirs in the Human Brain. Cells 2022; 11:2379. [PMID: 35954221 PMCID: PMC9367788 DOI: 10.3390/cells11152379] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/19/2022] [Accepted: 07/26/2022] [Indexed: 02/04/2023] Open
Abstract
The major barrier to cure HIV infection is the early generation and extended survival of HIV reservoirs in the circulation and tissues. Currently, the techniques used to detect and quantify HIV reservoirs are mostly based on blood-based assays; however, it has become evident that viral reservoirs remain in tissues. Our study describes a novel multi-component imaging method (HIV DNA, mRNA, and viral proteins in the same assay) to identify, quantify, and characterize viral reservoirs in tissues and blood products obtained from HIV-infected individuals even when systemic replication is undetectable. In the human brains of HIV-infected individuals under ART, we identified that microglia/macrophages and a small population of astrocytes are the main cells with integrated HIV DNA. Only half of the cells with integrated HIV DNA expressed viral mRNA, and one-third expressed viral proteins. Surprisingly, we identified residual HIV-p24, gp120, nef, vpr, and tat protein expression and accumulation in uninfected cells around HIV-infected cells suggesting local synthesis, secretion, and bystander uptake. In conclusion, our data show that ART reduces the size of the brain's HIV reservoirs; however, local/chronic viral protein secretion still occurs, indicating that the brain is still a major anatomical target to cure HIV infection.
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Affiliation(s)
| | | | | | | | | | - Eliseo A. Eugenin
- Department of Neuroscience, Cell Biology, and Anatomy, University of Texas Medical Branch (UTMB), Research Building 17, Fifth Floor, 105 11th Street, Galveston, TX 77555, USA; (M.D.); (D.D.); (S.V.); (C.A.H.); (B.P.)
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11
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Localization and functions of native and eGFP-tagged capsid proteins in HIV-1 particles. PLoS Pathog 2022; 18:e1010754. [PMID: 35951676 PMCID: PMC9426931 DOI: 10.1371/journal.ppat.1010754] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 08/30/2022] [Accepted: 07/21/2022] [Indexed: 12/24/2022] Open
Abstract
In infectious HIV-1 particles, the capsid protein (CA) forms a cone-shaped shell called the capsid, which encases the viral ribonucleoprotein complex (vRNP). Following cellular entry, the capsid is disassembled through a poorly understood process referred to as uncoating, which is required to release the reverse transcribed HIV-1 genome for integration into host chromatin. Whereas single virus imaging using indirect CA labeling techniques suggested uncoating to occur in the cytoplasm or at the nuclear pore, a recent study using eGFP-tagged CA reported uncoating in the nucleus. To delineate the HIV-1 uncoating site, we investigated the mechanism of eGFP-tagged CA incorporation into capsids and the utility of this fluorescent marker for visualizing HIV-1 uncoating. We find that virion incorporated eGFP-tagged CA is effectively excluded from the capsid shell, and that a subset of the tagged CA is vRNP associated. These results thus imply that eGFP-tagged CA is not a direct marker for capsid uncoating. We further show that native CA co-immunoprecipitates with vRNP components, providing a basis for retention of eGFP-tagged and untagged CA by sub-viral complexes in the nucleus. Moreover, we find that functional viral replication complexes become accessible to integrase-interacting host factors at the nuclear pore, leading to inhibition of infection and demonstrating capsid permeabilization prior to nuclear import. Finally, we find that HIV-1 cores containing a mixture of wild-type and mutant CA interact differently with cytoplasmic versus nuclear pools of the CA-binding host cofactor CPSF6. Our results suggest that capsid remodeling (including a loss of capsid integrity) is the predominant pathway for HIV-1 nuclear entry and provide new insights into the mechanism of CA retention in the nucleus via interaction with vRNP components. The timing, location and mechanisms of HIV-1 capsid disassembly which is referred to as uncoating remains unclear. Direct labeling of HIV-1 capsids, by incorporating a few green fluorescent proteins (GFP) tagged capsid protein (CA) into virions allows to image the spatio-temporal loss of HIV-1 CA during virus infection. However, the localization and functions of a few virion incorporated eGFP-tagged CA proteins remain unclear, since <50% of virus packaged CA proteins participate to form the conical capsid shell that protects the HIV-1 genome. Here we developed several approaches to test the localization and function of eGFP-tagged CA proteins in virions. We found that eGFP-tagged CA proteins are excluded from the conical capsid shell and that a subset of these proteins is associated with the viral ribonucleoprotein complex (vRNPs), through direct interactions between CA and vRNP components. eGFP-tagged CA is retained in the nucleus by virtue of vRNP association and is unlikely to report on HIV-1 capsid disassembly. We also found that HIV-1 capsids become permeabilized and are remodeled during their transport into the nucleus. Our study provides new insights into the ability of CA to interact with vRNPs for its retention in the nucleus and highlights capsid remodeling as a preferred pathway for HIV-1 entry into the nucleus.
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12
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Multi-Substituted Quinolines as HIV-1 Integrase Allosteric Inhibitors. Viruses 2022; 14:v14071466. [PMID: 35891446 PMCID: PMC9324412 DOI: 10.3390/v14071466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 01/25/2023] Open
Abstract
Allosteric HIV-1 integrase (IN) inhibitors, or ALLINIs, are a new class of antiviral agents that bind at the dimer interface of the IN, away from the enzymatic catalytic site and block viral replication by triggering an aberrant multimerization of the viral enzyme. To further our understanding of the important binding features of multi-substituted quinoline-based ALLINIs, we have examined the IN multimerization and antiviral properties of substitution patterns at the 6 or 8 position. We found that the binding properties of these ALLINIs are negatively impacted by the presence of bulky substitutions at these positions. In addition, we have observed that the addition of bromine at either the 6 (6-bromo) or 8 (8-bromo) position conferred better antiviral properties. Finally, we found a significant loss of potency with the 6-bromo when tested with the ALLINI-resistant IN A128T mutant virus, while the 8-bromo analog retained full effectiveness.
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13
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Engelman AN, Kvaratskhelia M. Multimodal Functionalities of HIV-1 Integrase. Viruses 2022; 14:926. [PMID: 35632668 PMCID: PMC9144474 DOI: 10.3390/v14050926] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/20/2022] [Accepted: 04/26/2022] [Indexed: 01/11/2023] Open
Abstract
Integrase is the retroviral protein responsible for integrating reverse transcripts into cellular genomes. Co-packaged with viral RNA and reverse transcriptase into capsid-encased viral cores, human immunodeficiency virus 1 (HIV-1) integrase has long been implicated in reverse transcription and virion maturation. However, the underlying mechanisms of integrase in these non-catalytic-related viral replication steps have remained elusive. Recent results have shown that integrase binds genomic RNA in virions, and that mutational or pharmacological disruption of integrase-RNA binding yields eccentric virion particles with ribonucleoprotein complexes situated outside of the capsid shell. Such viruses are defective for reverse transcription due to preferential loss of integrase and viral RNA from infected target cells. Parallel research has revealed defective integrase-RNA binding and eccentric particle formation as common features of class II integrase mutant viruses, a phenotypic grouping of viruses that display defects at steps beyond integration. In light of these new findings, we propose three new subclasses of class II mutant viruses (a, b, and c), all of which are defective for integrase-RNA binding and particle morphogenesis, but differ based on distinct underlying mechanisms exhibited by the associated integrase mutant proteins. We also assess how these findings inform the role of integrase in HIV-1 particle maturation.
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Affiliation(s)
- 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
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
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14
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Adu-Ampratwum D, Pan Y, Koneru PC, Antwi J, Hoyte AC, Kessl J, Griffin PR, Kvaratskhelia M, Fuchs JR, Larue RC. Identification and Optimization of a Novel HIV-1 Integrase Inhibitor. ACS OMEGA 2022; 7:4482-4491. [PMID: 35155940 PMCID: PMC8829933 DOI: 10.1021/acsomega.1c06378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/13/2022] [Indexed: 05/17/2023]
Abstract
Human immunodeficiency virus-1 (HIV-1) is the causative agent of acquired immunodeficiency syndrome (AIDS). HIV-1, like all retroviruses, stably integrates its vDNA copy into host chromatin, a process allowing for permanent infection. This essential step for HIV-1 replication is catalyzed by viral integrase (IN) and aided by cellular protein LEDGF/p75. In addition, IN is also crucial for proper virion maturation as it interacts with the viral RNA genome to ensure encapsulation of ribonucleoprotein complexes within the protective capsid core. These key functions make IN an attractive target for the development of inhibitors with various mechanisms of action. We conducted a high-throughput screen (HTS) of ∼370,000 compounds using a homogeneous time-resolved fluorescence-based assay capable of capturing diverse inhibitors targeting multifunctional IN. Our approach revealed chemical scaffolds containing diketo acid moieties similar to IN strand transfer inhibitors (INSTIs) as well as novel compounds distinct from all current IN inhibitors including INSTIs and allosteric integrase inhibitors (ALLINIs). Specifically, our HTS resulted in the discovery of compound 12, with a novel IN inhibitor scaffold amenable for chemical modification. Its more potent derivative 14e similarly inhibited catalytic activities of WT and mutant INs containing archetypical INSTI- and ALLINI-derived resistant substitutions. Further SAR-based optimization resulted in compound 22 with an antiviral EC50 of ∼58 μM and a selectivity index of >8500. Thus, our studies identified a novel small-molecule scaffold for inhibiting HIV-1 IN, which provides a promising platform for future development of potent antiviral agents to complement current HIV-1 therapies.
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Affiliation(s)
- Daniel Adu-Ampratwum
- Division
of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yuhan Pan
- Division
of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Pratibha C. Koneru
- Division
of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado 80045, United States
| | - Janet Antwi
- Division
of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ashley C. Hoyte
- Division
of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado 80045, United States
| | - Jacques Kessl
- Department
of Chemistry & Biochemistry, The University
of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Patrick R. Griffin
- Department
of Molecular Medicine, The Scripps Research
Institute, Jupiter, Florida 33458, United
States
| | - Mamuka Kvaratskhelia
- Division
of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
- Division
of Infectious Diseases, School of Medicine, University of Colorado, Aurora, Colorado 80045, United States
| | - James R. Fuchs
- Division
of Medicinal Chemistry & Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ross C. Larue
- Division
of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
- Department
of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
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15
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Abstract
A hallmark of retroviral replication is establishment of the proviral state, wherein a DNA copy of the viral RNA genome is stably incorporated into a host cell chromosome. Integrase is the viral enzyme responsible for the catalytic steps involved in this process, and integrase strand transfer inhibitors are widely used to treat people living with HIV. Over the past decade, a series of X-ray crystallography and cryogenic electron microscopy studies have revealed the structural basis of retroviral DNA integration. A variable number of integrase molecules congregate on viral DNA ends to assemble a conserved intasome core machine that facilitates integration. The structures additionally informed on the modes of integrase inhibitor action and the means by which HIV acquires drug resistance. Recent years have witnessed the development of allosteric integrase inhibitors, a highly promising class of small molecules that antagonize viral morphogenesis. In this Review, we explore recent insights into the organization and mechanism of the retroviral integration machinery and highlight open questions as well as new directions in the field.
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16
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Passos DO, Li M, Craigie R, Lyumkis D. Retroviral integrase: Structure, mechanism, and inhibition. Enzymes 2021; 50:249-300. [PMID: 34861940 DOI: 10.1016/bs.enz.2021.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The retroviral protein Integrase (IN) catalyzes concerted integration of viral DNA into host chromatin to establish a permanent infection in the target cell. We learned a great deal about the mechanism of catalytic integration through structure/function studies over the previous four decades of IN research. As one of three essential retroviral enzymes, IN has also been targeted by antiretroviral drugs to treat HIV-infected individuals. Inhibitors blocking the catalytic integration reaction are now state-of-the-art drugs within the antiretroviral therapy toolkit. HIV-1 IN also performs intriguing non-catalytic functions that are relevant to the late stages of the viral replication cycle, yet this aspect remains poorly understood. There are also novel allosteric inhibitors targeting non-enzymatic functions of IN that induce a block in the late stages of the viral replication cycle. In this chapter, we will discuss the function, structure, and inhibition of retroviral IN proteins, highlighting remaining challenges and outstanding questions.
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Affiliation(s)
| | - Min Li
- National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States
| | - Robert Craigie
- National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, United States
| | - Dmitry Lyumkis
- The Salk Institute for Biological Studies, La Jolla, CA, United States; The Scripps Research Institute, La Jolla, CA, United States.
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17
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Liu S, Koneru PC, Li W, Pathirage C, Engelman AN, Kvaratskhelia M, Musier-Forsyth K. HIV-1 integrase binding to genomic RNA 5'-UTR induces local structural changes in vitro and in virio. Retrovirology 2021; 18:37. [PMID: 34809662 PMCID: PMC8609798 DOI: 10.1186/s12977-021-00582-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 11/03/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND During HIV-1 maturation, Gag and Gag-Pol polyproteins are proteolytically cleaved and the capsid protein polymerizes to form the honeycomb capsid lattice. HIV-1 integrase (IN) binds the viral genomic RNA (gRNA) and impairment of IN-gRNA binding leads to mis-localization of the nucleocapsid protein (NC)-condensed viral ribonucleoprotein complex outside the capsid core. IN and NC were previously demonstrated to bind to the gRNA in an orthogonal manner in virio; however, the effect of IN binding alone or simultaneous binding of both proteins on gRNA structure is not yet well understood. RESULTS Using crosslinking-coupled selective 2'-hydroxyl acylation analyzed by primer extension (XL-SHAPE), we characterized the interaction of IN and NC with the HIV-1 gRNA 5'-untranslated region (5'-UTR). NC preferentially bound to the packaging signal (Psi) and a UG-rich region in U5, irrespective of the presence of IN. IN alone also bound to Psi but pre-incubation with NC largely abolished this interaction. In contrast, IN specifically bound to and affected the nucleotide (nt) dynamics of the apical loop of the transactivation response element (TAR) and the polyA hairpin even in the presence of NC. SHAPE probing of the 5'-UTR RNA in virions produced from allosteric IN inhibitor (ALLINI)-treated cells revealed that while the global secondary structure of the 5'-UTR remained unaltered, the inhibitor treatment induced local reactivity differences, including changes in the apical loop of TAR that are consistent with the in vitro results. CONCLUSIONS Overall, the binding interactions of NC and IN with the 5'-UTR are largely orthogonal in vitro. This study, together with previous probing experiments, suggests that IN and NC binding in vitro and in virio lead to only local structural changes in the regions of the 5'-UTR probed here. Accordingly, disruption of IN-gRNA binding by ALLINI treatment results in local rather than global secondary structure changes of the 5'-UTR in eccentric virus particles.
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Affiliation(s)
- Shuohui Liu
- grid.261331.40000 0001 2285 7943Department of Chemistry and Biochemistry, Centers for RNA Biology and Retroviral Research, The Ohio State University, Columbus, OH USA
| | - Pratibha C. Koneru
- grid.430503.10000 0001 0703 675XDivision of Infectious Diseases, School of Medicine, University of Colorado, Aurora, CO USA
| | - Wen Li
- grid.65499.370000 0001 2106 9910Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA USA ,grid.38142.3c000000041936754XDepartment of Medicine, Harvard Medical School, Boston, MA USA
| | - Chathuri Pathirage
- grid.261331.40000 0001 2285 7943Department of Chemistry and Biochemistry, Centers for RNA Biology and Retroviral Research, The Ohio State University, Columbus, OH USA
| | - Alan N. Engelman
- grid.65499.370000 0001 2106 9910Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, MA USA ,grid.38142.3c000000041936754XDepartment of Medicine, Harvard Medical School, Boston, MA USA
| | - Mamuka Kvaratskhelia
- grid.430503.10000 0001 0703 675XDivision of Infectious Diseases, School of Medicine, University of Colorado, Aurora, CO USA
| | - Karin Musier-Forsyth
- grid.261331.40000 0001 2285 7943Department of Chemistry and Biochemistry, Centers for RNA Biology and Retroviral Research, The Ohio State University, Columbus, OH USA
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18
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Maehigashi T, Ahn S, Kim UI, Lindenberger J, Oo A, Koneru PC, Mahboubi B, Engelman AN, Kvaratskhelia M, Kim K, Kim B. A highly potent and safe pyrrolopyridine-based allosteric HIV-1 integrase inhibitor targeting host LEDGF/p75-integrase interaction site. PLoS Pathog 2021; 17:e1009671. [PMID: 34293041 PMCID: PMC8297771 DOI: 10.1371/journal.ppat.1009671] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/27/2021] [Indexed: 12/03/2022] Open
Abstract
Allosteric integrase inhibitors (ALLINIs) are a class of experimental anti-HIV agents that target the noncatalytic sites of the viral integrase (IN) and interfere with the IN-viral RNA interaction during viral maturation. Here, we report a highly potent and safe pyrrolopyridine-based ALLINI, STP0404, displaying picomolar IC50 in human PBMCs with a >24,000 therapeutic index against HIV-1. X-ray structural and biochemical analyses revealed that STP0404 binds to the host LEDGF/p75 protein binding pocket of the IN dimer, which induces aberrant IN oligomerization and blocks the IN-RNA interaction. Consequently, STP0404 inhibits proper localization of HIV-1 RNA genomes in viral particles during viral maturation. Y99H and A128T mutations at the LEDGF/p75 binding pocket render resistance to STP0404. Extensive in vivo pharmacological and toxicity investigations demonstrate that STP0404 harbors outstanding therapeutic and safety properties. Overall, STP0404 is a potent and first-in-class ALLINI that targets LEDGF/p75 binding site and has advanced to a human trial.
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Affiliation(s)
- Tatsuya Maehigashi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, United States of America
| | | | - Uk-Il Kim
- ST Pharm Co., Ltd., Seoul, South Korea
| | - Jared Lindenberger
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Adrian Oo
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Pratibha C. Koneru
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Bijan Mahboubi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Alan N. Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | | | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia, United States of America
- Center for Drug Discovery, Children’s Healthcare of Atlanta, Atlanta, Georgia, United States of America
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19
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Zhao Y, Li L, Zhou Z, Chen M, Yang W, Luo H. Copper catalyzed five-component domino strategy for the synthesis of nicotinimidamides. Org Biomol Chem 2021; 19:3868-3872. [PMID: 33949559 DOI: 10.1039/d1ob00162k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A library of medicinally and synthetically important nicotinimidamides was synthesized by a copper-catalyzed multicomponent domino reaction of oxime esters, terminal ynones, sulfonyl azides, aryl aldehydes and acetic ammonium. Its synthetic pathway involves the formation of a highly reactive N-sulfonyl acetylketenimine, characterized by high selectivity, combinations of potential nucleophiles and electrophiles, mild reaction conditions and a wide substrate scope, and is a rare five-component example of a CuAAC/ring-opening reaction.
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Affiliation(s)
- Yu Zhao
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China.
| | - Li Li
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China.
| | - Zitong Zhou
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China.
| | - Man Chen
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China.
| | - Weiguang Yang
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China. and The Marine Biomedical Research Institute of Guangdong Zhanjiang, Zhanjiang, Guangdong 524023, China and Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, Guangdong 524023, China
| | - Hui Luo
- Guangdong Key Laboratory for Research and Development of Natural Drugs, The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang, 524023, China. and The Marine Biomedical Research Institute of Guangdong Zhanjiang, Zhanjiang, Guangdong 524023, China and Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang, Guangdong 524023, China
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20
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Gupta K, Allen A, Giraldo C, Eilers G, Sharp R, Hwang Y, Murali H, Cruz K, Janmey P, Bushman F, Van Duyne GD. Allosteric HIV Integrase Inhibitors Promote Formation of Inactive Branched Polymers via Homomeric Carboxy-Terminal Domain Interactions. Structure 2021; 29:213-225.e5. [PMID: 33357410 PMCID: PMC7935764 DOI: 10.1016/j.str.2020.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 11/04/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022]
Abstract
The major effect of allosteric HIV integrase (IN) inhibitors (ALLINIs) is observed during virion maturation, where ALLINI treatment interrupts IN-RNA interactions via drug-induced IN aggregation, leading to the formation of aberrant virions. To understand the structural changes that accompany drug-induced aggregation, we determined the soft matter properties of ALLINI-induced IN aggregates. Using small-angle neutron scattering, SEM, and rheology, we have discovered that the higher-order aggregates induced by ALLINIs have the characteristics of weak three-dimensional gels with a fractal-like character. Their formation is inhibited by the host factor LEDGF/p75, as well as ex vivo resistance substitutions. Mutagenesis and biophysical analyses reveal that homomeric carboxy-terminal domain interactions are required to achieve the branched-polymer nature of the ALLINI-induced aggregates. These studies provide key insight into the mechanisms of ALLINI action and resistance in the context of the crowded virion environment where ALLINIs exert their effect.
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Affiliation(s)
- Kushol Gupta
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, 809C Stellar-Chance Building, 422 Curie Boulevard, Philadelphia, PA 19105-6059, USA
| | - Audrey Allen
- Department of Microbiology, University of Pennsylvania School of Medicine, 426 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104-6076, USA
| | - Carolina Giraldo
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, 809C Stellar-Chance Building, 422 Curie Boulevard, Philadelphia, PA 19105-6059, USA
| | - Grant Eilers
- Department of Microbiology, University of Pennsylvania School of Medicine, 426 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104-6076, USA
| | - Robert Sharp
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, 809C Stellar-Chance Building, 422 Curie Boulevard, Philadelphia, PA 19105-6059, USA
| | - Young Hwang
- Department of Microbiology, University of Pennsylvania School of Medicine, 426 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104-6076, USA
| | - Hemma Murali
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, 809C Stellar-Chance Building, 422 Curie Boulevard, Philadelphia, PA 19105-6059, USA
| | - Katrina Cruz
- Department of Physiology, and Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104-6383, USA
| | - Paul Janmey
- Department of Physiology, and Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104-6383, USA
| | - Frederic Bushman
- Department of Microbiology, University of Pennsylvania School of Medicine, 426 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104-6076, USA.
| | - Gregory D Van Duyne
- Department of Biochemistry & Biophysics, Perelman School of Medicine, University of Pennsylvania, 809C Stellar-Chance Building, 422 Curie Boulevard, Philadelphia, PA 19105-6059, USA.
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21
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Optimized binding of substituted quinoline ALLINIs within the HIV-1 integrase oligomer. J Biol Chem 2021; 296:100363. [PMID: 33539919 PMCID: PMC7949159 DOI: 10.1016/j.jbc.2021.100363] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
During the integration step, human immunodeficiency virus type 1 integrase (IN) interacts with viral DNA and the cellular cofactor LEDGF/p75 to effectively integrate the reverse transcript into the host chromatin. Allosteric human immunodeficiency virus type 1 integrase inhibitors (ALLINIs) are a new class of antiviral agents that bind at the dimer interface of the IN catalytic core domain and occupy the binding site of LEDGF/p75. While originally designed to block IN-LEDGF/p75 interactions during viral integration, several of these compounds have been shown to also severely impact viral maturation through an IN multimerization mechanism. In this study, we tested the hypothesis that these dual properties of ALLINIs could be decoupled toward late stage viral replication effects by generating additional contact points between the bound ALLINI and a third subunit of IN. By sequential derivatization at position 7 of a quinoline-based ALLINI scaffold, we show that IN multimerization properties are enhanced by optimizing hydrophobic interactions between the compound and the C-terminal domain of the third IN subunit. These features not only improve the overall antiviral potencies of these compounds but also significantly shift the ALLINIs selectivity toward the viral maturation stage. Thus, we demonstrate that to fully maximize the potency of ALLINIs, the interactions between the inhibitor and all three IN subunits need to be simultaneously optimized.
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22
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Vanangamudi M, Nair PC, Engels SEM, Palaniappan S, Namasivayam V. Structural Insights to Human Immunodeficiency Virus (HIV-1) Targets and Their Inhibition. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1322:63-95. [PMID: 34258737 DOI: 10.1007/978-981-16-0267-2_3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Human immunodeficiency virus (HIV) is a deadly virus that attacks the body's immune system, subsequently leading to AIDS (acquired immunodeficiency syndrome) and ultimately death. Currently, there is no vaccine or effective cure for this infection; however, antiretrovirals that act at various phases of the virus life cycle have been useful to control the viral load in patients. One of the major problems with antiretroviral therapies involves drug resistance. The three-dimensional structure from crystallography studies are instrumental in understanding the structural basis of drug binding to various targets. This chapter provides key insights into different targets and drugs used in the treatment from a structural perspective. Specifically, an insight into the binding characteristics of drugs at the active and allosteric sites of different targets and the importance of targeting allosteric sites for design of new-generation antiretrovirals to overcome complex and resistant forms of the virus has been reviewed.
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Affiliation(s)
- Murugesan Vanangamudi
- Department of Pharmaceutical Chemistry, Amity Institute of Pharmacy, Amity University Gwalior, Gwalior, Madhya Pradesh, India
| | - Pramod C Nair
- Department of Clinical Pharmacology, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
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23
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Sun Q, Ramaswamy VSK, Levy R, Deng N. Computational design of small molecular modulators of protein-protein interactions with a novel thermodynamic cycle: Allosteric inhibitors of HIV-1 integrase. Protein Sci 2020; 30:438-447. [PMID: 33244804 DOI: 10.1002/pro.4004] [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: 10/27/2020] [Revised: 11/20/2020] [Accepted: 11/23/2020] [Indexed: 01/19/2023]
Abstract
Targeting protein-protein interactions for therapeutic development involves designing small molecules to either disrupt or enhance a known PPI. For this purpose, it is necessary to compute reliably the effect of chemical modifications of small molecules on the protein-protein association free energy. Here we present results obtained using a novel thermodynamic free energy cycle, for the rational design of allosteric inhibitors of HIV-1 integrase (ALLINI) that act specifically in the early stage of the infection cycle. The new compounds can serve as molecular probes to dissect the multifunctional mechanisms of ALLINIs to inform the discovery of new allosteric inhibitors. The free energy protocol developed here can be more broadly applied to study quantitatively the effects of small molecules on modulating the strengths of protein-protein interactions.
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Affiliation(s)
- Qinfang Sun
- Center for Biophysics and Computational Biology and Department of Chemistry, Temple University, Philadelphia, Pennsylvania, USA
| | - Vijayan S K Ramaswamy
- Institute for Applied Cancer Science, MD Anderson Cancer Center, Houston, Texas, USA
| | - Ronald Levy
- Center for Biophysics and Computational Biology and Department of Chemistry, Temple University, Philadelphia, Pennsylvania, USA
| | - Nanjie Deng
- Department of Chemistry and Physical Sciences, Pace University, New York, New York, USA
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24
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Kleinpeter A, Freed EO. How to package the RNA of HIV-1. eLife 2020; 9:63585. [PMID: 33200986 PMCID: PMC7671680 DOI: 10.7554/elife.63585] [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: 11/11/2020] [Accepted: 11/11/2020] [Indexed: 11/13/2022] Open
Abstract
Interactions between viral RNA and the integrase enzyme are required for HIV-1 particles to become infectious, a process that can be disrupted through multiple mechanisms.
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Affiliation(s)
- Alex Kleinpeter
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, United States
| | - Eric O Freed
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, United States
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25
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Structure-based amelioration of PXR transactivation in a novel series of macrocyclic allosteric inhibitors of HIV-1 integrase. Bioorg Med Chem Lett 2020; 30:127531. [DOI: 10.1016/j.bmcl.2020.127531] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/27/2020] [Accepted: 08/28/2020] [Indexed: 02/06/2023]
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26
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Phongsavanh X, Al-Qatabi N, Shaban MS, Khoder-Agha F, El Asri M, Comisso M, Guérois R, Mirande M. How HIV-1 Integrase Associates with Human Mitochondrial Lysyl-tRNA Synthetase. Viruses 2020; 12:v12101202. [PMID: 33096929 PMCID: PMC7589778 DOI: 10.3390/v12101202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/14/2020] [Accepted: 10/20/2020] [Indexed: 01/13/2023] Open
Abstract
Replication of human immunodeficiency virus type 1 (HIV-1) requires the packaging of tRNALys,3 from the host cell into the new viral particles. The GagPol viral polyprotein precursor associates with mitochondrial lysyl-tRNA synthetase (mLysRS) in a complex with tRNALys, an essential step to initiate reverse transcription in the virions. The C-terminal integrase moiety of GagPol is essential for its association with mLysRS. We show that integrases from HIV-1 and HIV-2 bind mLysRS with the same efficiency. In this work, we have undertaken to probe the three-dimensional (3D) architecture of the complex of integrase with mLysRS. We first established that the C-terminal domain (CTD) of integrase is the major interacting domain with mLysRS. Using the pBpa-photo crosslinking approach, inter-protein cross-links were observed involving amino acid residues located at the surface of the catalytic domain of mLysRS and of the CTD of integrase. In parallel, using molecular docking simulation, a single structural model of complex was found to outscore other alternative conformations. Consistent with crosslinking experiments, this structural model was further probed experimentally. Five compensatory mutations in the two partners were successfully designed which supports the validity of the model. The complex highlights that binding of integrase could stabilize the tRNALys:mLysRS interaction.
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27
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Bester SM, Wei G, Zhao H, Adu-Ampratwum D, Iqbal N, Courouble VV, Francis AC, Annamalai AS, Singh PK, Shkriabai N, Van Blerkom P, Morrison J, Poeschla EM, Engelman AN, Melikyan GB, Griffin PR, Fuchs JR, Asturias FJ, Kvaratskhelia M. Structural and mechanistic bases for a potent HIV-1 capsid inhibitor. Science 2020; 370:360-364. [PMID: 33060363 PMCID: PMC7831379 DOI: 10.1126/science.abb4808] [Citation(s) in RCA: 109] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 08/25/2020] [Indexed: 12/11/2022]
Abstract
The potent HIV-1 capsid inhibitor GS-6207 is an investigational principal component of long-acting antiretroviral therapy. We found that GS-6207 inhibits HIV-1 by stabilizing and thereby preventing functional disassembly of the capsid shell in infected cells. X-ray crystallography, cryo-electron microscopy, and hydrogen-deuterium exchange experiments revealed that GS-6207 tightly binds two adjoining capsid subunits and promotes distal intra- and inter-hexamer interactions that stabilize the curved capsid lattice. In addition, GS-6207 interferes with capsid binding to the cellular HIV-1 cofactors Nup153 and CPSF6 that mediate viral nuclear import and direct integration into gene-rich regions of chromatin. These findings elucidate structural insights into the multimodal, potent antiviral activity of GS-6207 and provide a means for rationally developing second-generation therapies.
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Affiliation(s)
- Stephanie M Bester
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Guochao Wei
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Haiyan Zhao
- Department of Biochemistry and Molecular Genetics, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Daniel Adu-Ampratwum
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA
| | - Naseer Iqbal
- Department of Biochemistry and Molecular Genetics, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Valentine V Courouble
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Ashwanth C Francis
- Department of Pediatrics, Infectious Diseases, Emory University, Atlanta, GA 30322, USA
| | - Arun S Annamalai
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Parmit K 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
| | - Nikoloz Shkriabai
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Peter Van Blerkom
- Department of Biochemistry and Molecular Genetics, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - James Morrison
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Eric M Poeschla
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, 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
| | - Gregory B Melikyan
- Department of Pediatrics, Infectious Diseases, Emory University, Atlanta, GA 30322, USA
| | - Patrick R Griffin
- Department of Molecular Medicine, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - James R Fuchs
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, USA
| | - Francisco J Asturias
- Department of Biochemistry and Molecular Genetics, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA.
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, Anschutz Medical Campus, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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28
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Elliott JL, Eschbach JE, Koneru PC, Li W, Puray-Chavez M, Townsend D, Lawson DQ, Engelman AN, Kvaratskhelia M, Kutluay SB. Integrase-RNA interactions underscore the critical role of integrase in HIV-1 virion morphogenesis. eLife 2020; 9:54311. [PMID: 32960169 PMCID: PMC7671690 DOI: 10.7554/elife.54311] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 09/22/2020] [Indexed: 01/29/2023] Open
Abstract
A large number of human immunodeficiency virus 1 (HIV-1) integrase (IN) alterations, referred to as class II substitutions, exhibit pleiotropic effects during virus replication. However, the underlying mechanism for the class II phenotype is not known. Here we demonstrate that all tested class II IN substitutions compromised IN-RNA binding in virions by one of the three distinct mechanisms: (i) markedly reducing IN levels thus precluding the formation of IN complexes with viral RNA; (ii) adversely affecting functional IN multimerization and consequently impairing IN binding to viral RNA; and (iii) directly compromising IN-RNA interactions without substantially affecting IN levels or functional IN multimerization. Inhibition of IN-RNA interactions resulted in the mislocalization of viral ribonucleoprotein complexes outside the capsid lattice, which led to premature degradation of the viral genome and IN in target cells. Collectively, our studies uncover causal mechanisms for the class II phenotype and highlight an essential role of IN-RNA interactions for accurate virion maturation.
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Affiliation(s)
- Jennifer L Elliott
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Jenna E Eschbach
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Pratibha C Koneru
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, United States
| | - Wen Li
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, United States.,Department of Medicine, Harvard Medical School, Boston, United States
| | - Maritza Puray-Chavez
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Dana Townsend
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Dana Q Lawson
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, United States.,Department of Medicine, Harvard Medical School, Boston, United States
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, United States
| | - Sebla B Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
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29
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Elliott JL, Kutluay SB. Going beyond Integration: The Emerging Role of HIV-1 Integrase in Virion Morphogenesis. Viruses 2020; 12:E1005. [PMID: 32916894 PMCID: PMC7551943 DOI: 10.3390/v12091005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/03/2020] [Accepted: 09/07/2020] [Indexed: 12/22/2022] Open
Abstract
The HIV-1 integrase enzyme (IN) plays a critical role in the viral life cycle by integrating the reverse-transcribed viral DNA into the host chromosome. This function of IN has been well studied, and the knowledge gained has informed the design of small molecule inhibitors that now form key components of antiretroviral therapy regimens. Recent discoveries unveiled that IN has an under-studied yet equally vital second function in human immunodeficiency virus type 1 (HIV-1) replication. This involves IN binding to the viral RNA genome in virions, which is necessary for proper virion maturation and morphogenesis. Inhibition of IN binding to the viral RNA genome results in mislocalization of the viral genome inside the virus particle, and its premature exposure and degradation in target cells. The roles of IN in integration and virion morphogenesis share a number of common elements, including interaction with viral nucleic acids and assembly of higher-order IN multimers. Herein we describe these two functions of IN within the context of the HIV-1 life cycle, how IN binding to the viral genome is coordinated by the major structural protein, Gag, and discuss the value of targeting the second role of IN in virion morphogenesis.
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Affiliation(s)
| | - Sebla B. Kutluay
- Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, MO 63110, USA;
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30
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Influence of the amino-terminal sequence on the structure and function of HIV integrase. Retrovirology 2020; 17:28. [PMID: 32867805 PMCID: PMC7457537 DOI: 10.1186/s12977-020-00537-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Accepted: 08/21/2020] [Indexed: 12/12/2022] Open
Abstract
Background Antiretroviral therapy (ART) can mitigate the morbidity and mortality caused by the human immunodeficiency virus (HIV). Successful development of ART can be accelerated by accurate structural and biochemical data on targets and their responses to inhibitors. One important ART target, HIV integrase (IN), has historically been studied in vitro in a modified form adapted to bacterial overexpression, with a methionine or a longer fusion protein sequence at the N-terminus. In contrast, IN present in viral particles is produced by proteolytic cleavage of the Pol polyprotein, which leaves a phenylalanine at the N-terminus (IN 1F). Inspection of available structures suggested that added residues on the N-terminus might disrupt proper protein folding and formation of multimeric complexes. Results We purified HIV-1 IN 1F1–212 and solved its structure at 2.4 Å resolution, which showed extension of an N-terminal helix compared to the published structure of IN1–212. Full-length IN 1F showed increased in vitro catalytic activity in assays of coupled joining of the two viral DNA ends compared to two IN variants containing additional N-terminal residues. IN 1F was also altered in its sensitivity to inhibitors, showing decreased sensitivity to the strand-transfer inhibitor raltegravir and increased sensitivity to allosteric integrase inhibitors. In solution, IN 1F exists as monomers and dimers, in contrast to other IN preparations which exist as higher-order oligomers. Conclusions The structural, biochemical, and biophysical characterization of IN 1F reveals the conformation of the native HIV-1 IN N-terminus and accompanying unique biochemical and biophysical properties. IN 1F thus represents an improved reagent for use in integration reactions in vitro and the development of antiretroviral agents.
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31
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Tse C, Wickstrom L, Kvaratskhelia M, Gallicchio E, Levy R, Deng N. Exploring the Free-Energy Landscape and Thermodynamics of Protein-Protein Association. Biophys J 2020; 119:1226-1238. [PMID: 32877664 DOI: 10.1016/j.bpj.2020.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/04/2020] [Accepted: 08/06/2020] [Indexed: 01/30/2023] Open
Abstract
We report the free-energy landscape and thermodynamics of the protein-protein association responsible for the drug-induced multimerization of HIV-1 integrase (IN). Allosteric HIV-1 integrase inhibitors promote aberrant IN multimerization by bridging IN-IN intermolecular interactions. However, the thermodynamic driving forces and kinetics of the multimerization remain largely unknown. Here, we explore the early steps in the IN multimerization by using umbrella sampling and unbiased molecular dynamics simulations in explicit solvent. In direct simulations, the two initially separated dimers spontaneously associate to form near-native complexes that resemble the crystal structure of the aberrant tetramer. Most strikingly, the effective interaction of the protein-protein association is very short-ranged: the two dimers associate rapidly within tens of nanoseconds when their binding surfaces are separated by d ≤ 4.3 Å (less than two water diameters). Beyond this distance, the oligomerization kinetics appears to be diffusion controlled with a much longer association time. The free-energy profile also captured the crucial role of allosteric IN inhibitors in promoting multimerization and explained why several C-terminal domain mutations are remarkably resistant to the drug-induced multimerization. The results also show that at small separation, the protein-protein binding process contains two consecutive phases with distinct thermodynamic signatures. First, interprotein water molecules are expelled to the bulk, resulting in a small increase in entropy, as the solvent entropy gain from the water release is nearly cancelled by the loss of side-chain entropies as the two proteins approach each other. At shorter distances, the two dry binding surfaces adapt to each other to optimize their interaction energy at the expense of further protein configurational entropy loss. Although the binding interfaces feature clusters of hydrophobic residues, overall, the protein-protein association in this system is driven by enthalpy and opposed by entropy.
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Affiliation(s)
- Celine Tse
- Department of Chemistry and Physical Sciences, Pace University, New York, New York
| | - Lauren Wickstrom
- Borough of Manhattan Community College, the City University of New York, Department of Science, New York, New York
| | - Mamuka Kvaratskhelia
- Division of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado
| | - Emilio Gallicchio
- Department of Chemistry, Brooklyn College, the City University of New York, Brooklyn, New York; PhD Program in Biochemistry and PhD Program in Chemistry, The Graduate Center of the City University of New York, New York, New York
| | - Ronald Levy
- Center for Biophysics and Computational Biology and Department of Chemistry, Temple University, Philadelphia, Pennsylvania
| | - Nanjie Deng
- Department of Chemistry and Physical Sciences, Pace University, New York, New York.
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32
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Shinde PB, Bhowmick S, Alfantoukh E, Patil PC, Wabaidur SM, Chikhale RV, Islam MA. De novo design based identification of potential HIV-1 integrase inhibitors: A pharmacoinformatics study. Comput Biol Chem 2020; 88:107319. [PMID: 32801062 DOI: 10.1016/j.compbiolchem.2020.107319] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/10/2020] [Accepted: 06/22/2020] [Indexed: 12/30/2022]
Abstract
In the present study, pharmacoinformatics paradigms include receptor-based de novo design, virtual screening through molecular docking and molecular dynamics (MD) simulation are implemented to identify novel and promising HIV-1 integrase inhibitors. The de novodrug/ligand/molecule design is a powerful and effective approach to design a large number of novel and structurally diverse compounds with the required pharmacological profiles. A crystal structure of HIV-1 integrase bound with standard inhibitor BI-224436 is used and a set of 80,000 compounds through the de novo approach in LigBuilder is designed. Initially, a number of criteria including molecular docking, in-silico toxicity and pharmacokinetics profile assessments are implied to reduce the chemical space. Finally, four de novo designed molecules are proposed as potential HIV-1 integrase inhibitors based on comparative analyses. Notably, strong binding interactions have been identified between a few newly identified catalytic amino acid residues and proposed HIV-1 integrase inhibitors. For evaluation of the dynamic stability of the protein-ligand complexes, a number of parameters are explored from the 100 ns MD simulation study. The MD simulation study suggested that proposed molecules efficiently retained their molecular interaction and structural integrity inside the HIV-1 integrase. The binding free energy is calculated through the Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) approach for all complexes and it also explains their thermodynamic stability. Hence, proposed molecules through de novo design might be critical to inhibiting the HIV-1 integrase.
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Affiliation(s)
- Pooja Balasaheb Shinde
- Department of Bioinformatics, Rajiv Gandhi Institute of IT and Biotechnology, Bharati Vidyapeeth Deemed University, Pune-Satara Road, Pune, India
| | - Shovonlal Bhowmick
- Department of Chemical Technology, University of Calcutta, 92, A.P.C. Road, Kolkata, 700009, India
| | - Etidal Alfantoukh
- Health Sciences Research Center, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Pritee Chunarkar Patil
- Department of Bioinformatics, Rajiv Gandhi Institute of IT and Biotechnology, Bharati Vidyapeeth Deemed University, Pune-Satara Road, Pune, India
| | - Saikh Mohammad Wabaidur
- Department of Chemistry P.O. Box 2455, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Rupesh V Chikhale
- School of Pharmacy, University of East Anglia, Norwich, United Kingdom
| | - Md Ataul Islam
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom; School of Health Sciences, University of Kwazulu-Natal, Westville Campus, Durban, South Africa; Department of Chemical Pathology, Faculty of Health Sciences, University of Pretoria and National Health Laboratory Service Tshwane Academic Division, Pretoria, South Africa.
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33
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Cruz J, Wickstrom L, Yang D, Gallicchio E, Deng N. Combining Alchemical Transformation with a Physical Pathway to Accelerate Absolute Binding Free Energy Calculations of Charged Ligands to Enclosed Binding Sites. J Chem Theory Comput 2020; 16:2803-2813. [PMID: 32101691 DOI: 10.1021/acs.jctc.9b01119] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
We present a new approach to more accurately and efficiently compute the absolute binding free energy for receptor-ligand complexes. Currently, the double decoupling method (DDM) and the potential of mean force method (PMF) are widely used to compute the absolute binding free energy of biomolecular complexes. DDM relies on alchemically decoupling the ligand from its environments, which can be computationally challenging for large ligands and charged ligands because of the large magnitude of the decoupling free energies involved. In contrast, the PMF method uses a physical pathway to directly transfer the ligand from solution to the receptor binding pocket and thus avoids some of the aforementioned problems in DDM. However, the PMF method has its own drawbacks: because of its reliance on a ligand binding/unbinding pathway that is free of steric obstructions from the receptor atoms, the method has difficulty treating ligands with buried atoms. To overcome the limitation in the standard PMF approach and enable buried ligands to be treated, here we develop a new method called AlchemPMF in which steric obstructions along the physical pathway for binding are alchemically removed. We have tested the new approach on two important drug targets involving charged ligands. One is HIV-1 integrase bound to an allosteric inhibitor; the other is the human telomeric DNA G-quadruplex in complex with a natural product protoberberine buried in the binding pocket. For both systems, the new approach leads to more reliable estimates of absolute binding free energies with smaller error bars and closer agreements with experiments compared with those obtained from the existing methods, demonstrating the effectiveness of the new method in overcoming the hysteresis often encountered in PMF binding free energy calculations of such systems. The new approach could also be used to improve the sampling of water equilibration and resolvation of the binding pocket as the ligand is extracted.
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Affiliation(s)
- Jeffrey Cruz
- Department of Chemistry and Physical Sciences, Pace University, New York, New York 10038, United States
| | - Lauren Wickstrom
- Department of Science, Borough of Manhattan Community College, The City University of New York, New York, New York 10007, United States
| | - Danzhou Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, Indiana 47907, United States
| | - Emilio Gallicchio
- Department of Chemistry, Brooklyn College, The City University of New York, Brooklyn, New York 11210, United States.,Ph.D. Program in Biochemistry, Graduate Center, City University of New York, New York, New York 10016, United States.,Ph.D. Program in Chemistry, Graduate Center, City University of New York, New York, New York 10016, United States
| | - Nanjie Deng
- Department of Chemistry and Physical Sciences, Pace University, New York, New York 10038, United States
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34
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Anderson-Daniels J, Singh PK, Sowd GA, Li W, Engelman AN, Aiken C. Dominant Negative MA-CA Fusion Protein Is Incorporated into HIV-1 Cores and Inhibits Nuclear Entry of Viral Preintegration Complexes. J Virol 2019; 93:e01118-19. [PMID: 31413124 PMCID: PMC6803256 DOI: 10.1128/jvi.01118-19] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [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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Affiliation(s)
- Jordan Anderson-Daniels
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Parmit K Singh
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Gregory A Sowd
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Wen Li
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts, USA
- Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Christopher Aiken
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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35
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Engelman AN. Multifaceted HIV integrase functionalities and therapeutic strategies for their inhibition. J Biol Chem 2019; 294:15137-15157. [PMID: 31467082 DOI: 10.1074/jbc.rev119.006901] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Antiretroviral inhibitors that are used to manage HIV infection/AIDS predominantly target three enzymes required for virus replication: reverse transcriptase, protease, and integrase. Although integrase inhibitors were the last among this group to be approved for treating people living with HIV, they have since risen to the forefront of treatment options. Integrase strand transfer inhibitors (INSTIs) are now recommended components of frontline and drug-switch antiretroviral therapy formulations. Integrase catalyzes two successive magnesium-dependent polynucleotidyl transferase reactions, 3' processing and strand transfer, and INSTIs tightly bind the divalent metal ions and viral DNA end after 3' processing, displacing from the integrase active site the DNA 3'-hydroxyl group that is required for strand transfer activity. Although second-generation INSTIs present higher barriers to the development of viral drug resistance than first-generation compounds, the mechanisms underlying these superior barrier profiles are incompletely understood. A separate class of HIV-1 integrase inhibitors, the allosteric integrase inhibitors (ALLINIs), engage integrase distal from the enzyme active site, namely at the binding site for the cellular cofactor lens epithelium-derived growth factor (LEDGF)/p75 that helps to guide integration into host genes. ALLINIs inhibit HIV-1 replication by inducing integrase hypermultimerization, which precludes integrase binding to genomic RNA and perturbs the morphogenesis of new viral particles. Although not yet approved for human use, ALLINIs provide important probes that can be used to investigate the link between HIV-1 integrase and viral particle morphogenesis. Herein, I review the mechanisms of retroviral integration as well as the promises and challenges of using integrase inhibitors for HIV/AIDS management.
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Affiliation(s)
- Alan N Engelman
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Boston, Massachusetts 02215 Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115
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