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Zhu Y, Kleinpeter AB, Rey JS, Shen J, Shen Y, Xu J, Hardenbrook N, Chen L, Lucic A, Perilla JR, Freed EO, Zhang P. Structural basis for HIV-1 capsid adaption to rescue IP6-packaging deficiency. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2025.02.09.637297. [PMID: 39975075 PMCID: PMC11839029 DOI: 10.1101/2025.02.09.637297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 02/21/2025]
Abstract
Inositol hexakisphosphate (IP6) promotes HIV-1 assembly via its interaction with the immature Gag lattice, effectively enriching IP6 within virions. During particle maturation, the HIV-1 protease cleaves the Gag polyproteins comprising the immature Gag lattice, releasing IP6 from its original binding site and liberating the capsid (CA) domain of Gag. IP6 then promotes the assembly of mature CA protein into the capsid shell of the viral core, which is required for infection of new target cells. Recently, we reported HIV-1 Gag mutants that assemble virions independently of IP6. However, these mutants are non-infectious and unable to assemble stable capsids. Here, we identified a mutation in the C-terminus of CA - G225R - that restores capsid formation and infectivity to these IP6-packaging-deficient mutants. Furthermore, we show that G225R facilitates the in vitro assembly of purified CA into capsid-like particles (CLPs) at IP6 concentrations well below those required for WT CLP assembly. Using single-particle cryoEM, we solved structures of CA hexamer and hexameric lattice of mature CLPs harbouring the G225R mutation assembled in low-IP6 conditions. The high-resolution (2.7 Å) cryoEM structure combined with molecular dynamics simulations of the G225R capsid revealed that the otherwise flexible and disordered C-terminus of CA becomes structured, extending to the pseudo two-fold hexamer-hexamer interface, thereby stabilizing the mature capsid. This work uncovers a structural mechanism by which HIV-1 adapts to a deficiency in IP6 packaging. Furthermore, the ability of G225R to promote mature capsid assembly in low-IP6 conditions provides a valuable tool for capsid-related studies and may indicate a heretofore unknown role for the unstructured C-terminus in HIV-1 capsid assembly.
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Affiliation(s)
- Yanan Zhu
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
- Institute for Advanced Study in Physics, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Alex B Kleinpeter
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Juan S. Rey
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Juan Shen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Yao Shen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Jialu Xu
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Nathan Hardenbrook
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Long Chen
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Anka Lucic
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Juan R. Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford OX3 7BN, UK
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2
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Obr M, Percipalle M, Chernikova D, Yang H, Thader A, Pinke G, Porley D, Mansky LM, Dick RA, Schur FKM. Distinct stabilization of the human T cell leukemia virus type 1 immature Gag lattice. Nat Struct Mol Biol 2025; 32:268-276. [PMID: 39242978 PMCID: PMC11832423 DOI: 10.1038/s41594-024-01390-8] [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: 07/24/2023] [Accepted: 08/14/2024] [Indexed: 09/09/2024]
Abstract
Human T cell leukemia virus type 1 (HTLV-1) immature particles differ in morphology from other retroviruses, suggesting a distinct way of assembly. Here we report the results of cryo-electron tomography studies of HTLV-1 virus-like particles assembled in vitro, as well as derived from cells. This work shows that HTLV-1 uses a distinct mechanism of Gag-Gag interactions to form the immature viral lattice. Analysis of high-resolution structural information from immature capsid (CA) tubular arrays reveals that the primary stabilizing component in HTLV-1 is the N-terminal domain of CA. Mutagenesis analysis supports this observation. This distinguishes HTLV-1 from other retroviruses, in which the stabilization is provided primarily by the C-terminal domain of CA. These results provide structural details of the quaternary arrangement of Gag for an immature deltaretrovirus and this helps explain why HTLV-1 particles are morphologically distinct.
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Affiliation(s)
- Martin Obr
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
- Material and Structural Analysis Division, Thermo Fisher Scientific, Achtseweg Noord, Eindhoven, Netherlands
| | - Mathias Percipalle
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Darya Chernikova
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Huixin Yang
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
| | - Andreas Thader
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Gergely Pinke
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Dario Porley
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Louis M Mansky
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
| | - Robert A Dick
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
- Department of Pediatrics, Laboratory of Biochemical Pharmacology, Center for ViroScience and Cure, Emory University School of Medicine, Atlanta, GA, USA
| | - Florian K M Schur
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria.
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3
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González SA, Affranchino JL. The life cycle of feline immunodeficiency virus. Virology 2025; 601:110304. [PMID: 39561619 DOI: 10.1016/j.virol.2024.110304] [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] [Received: 10/09/2024] [Revised: 11/10/2024] [Accepted: 11/13/2024] [Indexed: 11/21/2024]
Abstract
Feline immunodeficiency virus (FIV) is a retrovirus of worldwide distribution that can cause an acquired immunodeficiency disease in domestic cats. FIV and the primate lentiviruses, human and simian immunodeficiency viruses (HIV and SIV, respectively) share structural and biological features but also exhibit important differences, which reflect both their evolutionary relationship and divergence. Given that FIV is not only an important cat pathogen but also a useful model for certain aspects of HIV-1 infections in humans, the study of FIV biology is highly relevant. In this review we provide an updated description of the molecular mechanisms involved in each stage of the FIV life cycle.
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Affiliation(s)
- Silvia A González
- Laboratorio de Virología, Facultad de Ciencias Exactas y Naturales, Universidad de Belgrano (UB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
| | - José L Affranchino
- Centro de Virología Humana y Animal (CEVHAN), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Abierta Interamericana (UAI), Buenos Aires, Argentina
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4
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McGraw A, Hillmer G, Medehincu SM, Hikichi Y, Gagliardi S, Narayan K, Tibebe H, Marquez D, Mei Bose L, Keating A, Izumi C, Peese K, Joshi S, Krystal M, DeCicco-Skinner KL, Freed EO, Sardo L, Izumi T. Exploring HIV-1 Maturation: A New Frontier in Antiviral Development. Viruses 2024; 16:1423. [PMID: 39339899 PMCID: PMC11437483 DOI: 10.3390/v16091423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2024] [Revised: 09/01/2024] [Accepted: 09/03/2024] [Indexed: 09/30/2024] Open
Abstract
HIV-1 virion maturation is an essential step in the viral replication cycle to produce infectious virus particles. Gag and Gag-Pol polyproteins are assembled at the plasma membrane of the virus-producer cells and bud from it to the extracellular compartment. The newly released progeny virions are initially immature and noninfectious. However, once the Gag polyprotein is cleaved by the viral protease in progeny virions, the mature capsid proteins assemble to form the fullerene core. This core, harboring two copies of viral genomic RNA, transforms the virion morphology into infectious virus particles. This morphological transformation is referred to as maturation. Virion maturation influences the distribution of the Env glycoprotein on the virion surface and induces conformational changes necessary for the subsequent interaction with the CD4 receptor. Several host factors, including proteins like cyclophilin A, metabolites such as IP6, and lipid rafts containing sphingomyelins, have been demonstrated to have an influence on virion maturation. This review article delves into the processes of virus maturation and Env glycoprotein recruitment, with an emphasis on the role of host cell factors and environmental conditions. Additionally, we discuss microscopic technologies for assessing virion maturation and the development of current antivirals specifically targeting this critical step in viral replication, offering long-acting therapeutic options.
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Affiliation(s)
- Aidan McGraw
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Grace Hillmer
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Stefania M. Medehincu
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Yuta Hikichi
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MS 21702, USA; (Y.H.); (E.O.F.)
| | - Sophia Gagliardi
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Kedhar Narayan
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Hasset Tibebe
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Dacia Marquez
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Lilia Mei Bose
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Adleigh Keating
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Coco Izumi
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Kevin Peese
- ViiV Healthcare, 36 E. Industrial Road, Branford, CT 06405, USA; (K.P.) (S.J.); (M.K.)
| | - Samit Joshi
- ViiV Healthcare, 36 E. Industrial Road, Branford, CT 06405, USA; (K.P.) (S.J.); (M.K.)
| | - Mark Krystal
- ViiV Healthcare, 36 E. Industrial Road, Branford, CT 06405, USA; (K.P.) (S.J.); (M.K.)
| | - Kathleen L. DeCicco-Skinner
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
| | - Eric O. Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MS 21702, USA; (Y.H.); (E.O.F.)
| | - Luca Sardo
- ViiV Healthcare, 36 E. Industrial Road, Branford, CT 06405, USA; (K.P.) (S.J.); (M.K.)
| | - Taisuke Izumi
- Department Biology, College of Arts and Sciences, American University, Washington, DC 20016, USA; (A.M.); (G.H.); (S.M.M.); (S.G.); (K.N.); (H.T.); (D.M.); (L.M.B.); (A.K.); (C.I.); (K.L.D.-S.)
- District of Columbia Center for AIDS Research, Washington, DC 20052, USA
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5
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K C Y, Pal S, Nitz TJ, Wild C, Gaur R. Construction of a HIV-1 subtype C 3D model using homology modeling and in-silico docking, molecular dynamics simulation, and MM-GBSA calculation of second-generation HIV-1 maturation inhibitor(s). J Biomol Struct Dyn 2024; 42:7150-7159. [PMID: 37489057 DOI: 10.1080/07391102.2023.2238079] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 07/13/2023] [Indexed: 07/26/2023]
Abstract
Maturation inhibitors (MIs) efficiently block HIV-1 maturation by inhibiting the cleavage of the capsid protein and spacer peptide 1 (CA-SP1) leading to the production of immature and non-infectious virus particles. We have previously reported that second-generation MIs were more potent than bevirimat (BVM) against HIV-1 subtype C. In-silico studies on interaction of with BVM and their analogs have been limited to HIV-1 subtype B(5I4T) due to lack of an available 3D structure for HIV-1 subtype C virus. In our current study, we have developed a 3D model of HIV-1C Gag CA-SP1 region using protein homology modeling with HIV-1 subtype B(514T) as a template. The HIV-1 C homology model generated was extensively validated using several online tools and served as a template to perform molecular docking studies with eight well-characterized MIs. The docked complex of HIV-1C and all nine MIs was subjected to molecular dynamics simulation for 100 ns using AMBER and binding free energy calculations were done using MM-GBSA. Based on our data, CV8611 exhibited highest binding energy of -6.5 Kcal/mol among all BVM analogs. CV8611 formed strong interactions with Gly222 and Met235 of HIV-1C Gag CA-SP1 during MD simulation and remained intact. The root mean square deviation and root mean square fluctuation values of the complex were stable during the simulations. Our study is the first to report construction and validation of 3D model for the HIV-1C Gag CA-SP1, which could serve as a crucial tool in the structure-aided design of novel and broadly acting maturation inhibitors.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Yuvraj K C
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, India
| | - Sapna Pal
- Bioinformatics centre, National Institute of Immunology, New Delhi, India
| | - T J Nitz
- DFH Pharma, Gaithersburg, MD, USA
| | | | - Ritu Gaur
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, India
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6
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Banerjee P, Voth GA. Conformational transitions of the HIV-1 Gag polyprotein upon multimerization and gRNA binding. Biophys J 2024; 123:42-56. [PMID: 37978800 PMCID: PMC10808027 DOI: 10.1016/j.bpj.2023.11.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 10/25/2023] [Accepted: 11/16/2023] [Indexed: 11/19/2023] Open
Abstract
During the HIV-1 assembly process, the Gag polyprotein multimerizes at the producer cell plasma membrane, resulting in the formation of spherical immature virus particles. Gag-genomic RNA (gRNA) interactions play a crucial role in the multimerization process, which is yet to be fully understood. We performed large-scale all-atom molecular dynamics simulations of membrane-bound full-length Gag dimer, hexamer, and 18-mer. The inter-domain dynamic correlation of Gag, quantified by the heterogeneous elastic network model applied to the simulated trajectories, is observed to be altered by implicit gRNA binding, as well as the multimerization state of the Gag. The lateral dynamics of our simulated membrane-bound Gag proteins, with and without gRNA binding, agree with prior experimental data and help to validate our simulation models and methods. The gRNA binding is observed to affect mainly the SP1 domain of the 18-mer and the matrix-capsid linker domain of the hexamer. In the absence of gRNA binding, the independent dynamical motion of the nucleocapsid domain results in a collapsed state of the dimeric Gag. Unlike stable SP1 helices in the six-helix bundle, without IP6 binding, the SP1 domain undergoes a spontaneous helix-to-coil transition in the dimeric Gag. Together, our findings reveal conformational switches of Gag at different stages of the multimerization process and predict that the gRNA binding reinforces an efficient binding surface of Gag for multimerization, and also regulates the dynamic organization of the local membrane region itself.
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Affiliation(s)
- Puja Banerjee
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois.
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7
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Banerjee P, Voth GA. Conformational transitions of the HIV-1 Gag polyprotein upon multimerization and gRNA binding. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.16.553549. [PMID: 37645781 PMCID: PMC10462060 DOI: 10.1101/2023.08.16.553549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
During the HIV-1 assembly process, the Gag polyprotein multimerizes at the producer cell plasma membrane, resulting in the formation of spherical immature virus particles. Gag-gRNA interactions play a crucial role in the multimerization process, which is yet to be fully understood. We have performed large-scale all-atom molecular dynamics simulations of membrane-bound full-length Gag dimer, hexamer, and 18-mer. The inter-domain dynamic correlation of Gag, quantified by the heterogeneous elastic network model (hENM) applied to the simulated trajectories, is observed to be altered by implicit gRNA binding, as well as the multimerization state of the Gag. The lateral dynamics of our simulated membrane-bound Gag proteins, with and without gRNA binding, agree with prior experimental data and help to validate our simulation models and methods. The gRNA binding is observed to impact mainly the SP1 domain of the 18-mer and the MA-CA linker domain of the hexamer. In the absence of gRNA binding, the independent dynamical motion of the NC domain results in a collapsed state of the dimeric Gag. Unlike stable SP1 helices in the six-helix bundle, without IP6 binding, the SP1 domain undergoes a spontaneous helix-to-coil transition in the dimeric Gag. Together, our findings reveal conformational switches of Gag at different stages of the multimerization process and predict that the gRNA binding reinforces an efficient binding surface of Gag for multimerization, as well as regulates the dynamic organization of the local membrane region itself. Significance Gag(Pr 55 Gag ) polyprotein orchestrates many essential events in HIV-1 assembly, including packaging of the genomic RNA (gRNA) in the immature virion. Although various experimental techniques, such as cryo-ET, X-ray, and NMR, have revealed structural properties of individual domains in the immature Gag clusters, structural and biophysical characterization of a full-length Gag molecule remains a challenge for existing experimental techniques. Using atomistic molecular dynamics simulations of the different model systems of Gag polyprotein, we present here a detailed structural characterization of Gag molecules in different multimerization states and interrogate the synergy between Gag-Gag, Gag-membrane, and Gag-gRNA interactions during the viral assembly process.
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8
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Meanwell NA. Sub-stoichiometric Modulation of Viral Targets-Potent Antiviral Agents That Exploit Target Vulnerability. ACS Med Chem Lett 2023; 14:1021-1030. [PMID: 37583823 PMCID: PMC10424314 DOI: 10.1021/acsmedchemlett.3c00279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 06/30/2023] [Indexed: 08/17/2023] Open
Abstract
The modulation of oligomeric viral targets at sub-stoichiometric ratios of drug to target has been advocated for its efficacy and potency, but there are only a limited number of documented examples. In this Viewpoint, we summarize the invention of the HIV-1 maturation inhibitor fipravirimat and discuss the emerging details around the mode of action of this class of drug that reflects inhibition of a protein composed of 1,300-1,600 monomers that interact in a cooperative fashion. Similarly, the HCV NS5A inhibitor daclatasvir has been shown to act in a highly sub-stoichiometric fashion, inhibiting viral replication at concentrations that are ∼23,500 lower than that of the protein target.
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9
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Qian Y, Evans D, Mishra B, Fu Y, Liu ZH, Guo S, Johnson ME. Temporal control by cofactors prevents kinetic trapping in retroviral Gag lattice assembly. Biophys J 2023; 122:3173-3190. [PMID: 37393432 PMCID: PMC10432227 DOI: 10.1016/j.bpj.2023.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/03/2023] Open
Abstract
For retroviruses like HIV to proliferate, they must form virions shaped by the self-assembly of Gag polyproteins into a rigid lattice. This immature Gag lattice has been structurally characterized and reconstituted in vitro, revealing the sensitivity of lattice assembly to multiple cofactors. Due to this sensitivity, the energetic criterion for forming stable lattices is unknown, as are their corresponding rates. Here, we use a reaction-diffusion model designed from the cryo-ET structure of the immature Gag lattice to map a phase diagram of assembly outcomes controlled by experimentally constrained rates and free energies, over experimentally relevant timescales. We find that productive assembly of complete lattices in bulk solution is extraordinarily difficult due to the large size of this ∼3700 monomer complex. Multiple Gag lattices nucleate before growth can complete, resulting in loss of free monomers and frequent kinetic trapping. We therefore derive a time-dependent protocol to titrate or "activate" the Gag monomers slowly within the solution volume, mimicking the biological roles of cofactors. This general strategy works remarkably well, yielding productive growth of self-assembled lattices for multiple interaction strengths and binding rates. By comparing to the in vitro assembly kinetics, we can estimate bounds on rates of Gag binding to Gag and the cellular cofactor IP6. Our results show that Gag binding to IP6 can provide the additional time delay necessary to support smooth growth of the immature lattice with relatively fast assembly kinetics, mostly avoiding kinetic traps. Our work provides a foundation for predicting and disrupting formation of the immature Gag lattice via targeting specific protein-protein binding interactions.
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Affiliation(s)
- Yian Qian
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Daniel Evans
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Bhavya Mishra
- Department of Physics, and Center for Cellular and Biomolecular Machines, University of California, Merced, California
| | - Yiben Fu
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Zixiu Hugh Liu
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Sikao Guo
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Margaret E Johnson
- TC Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland.
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10
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Obr M, Percipalle M, Chernikova D, Yang H, Thader A, Pinke G, Porley D, Mansky LM, Dick RA, Schur FKM. Unconventional stabilization of the human T-cell leukemia virus type 1 immature Gag lattice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.24.548988. [PMID: 37546793 PMCID: PMC10402013 DOI: 10.1101/2023.07.24.548988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Human T-cell leukemia virus type 1 (HTLV-1) has an atypical immature particle morphology compared to other retroviruses. This indicates that these particles are formed in a way that is unique. Here we report the results of cryo-electron tomography (cryo-ET) studies of HTLV-1 virus-like particles (VLPs) assembled in vitro, as well as derived from cells. This work shows that HTLV-1 employs an unconventional mechanism of Gag-Gag interactions to form the immature viral lattice. Analysis of high-resolution structural information from immature CA tubular arrays reveals that the primary stabilizing component in HTLV-1 is CA-NTD. Mutagenesis and biophysical analysis support this observation. This distinguishes HTLV-1 from other retroviruses, in which the stabilization is provided primarily by the CA-CTD. These results are the first to provide structural details of the quaternary arrangement of Gag for an immature deltaretrovirus, and this helps explain why HTLV-1 particles are morphologically distinct.
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Affiliation(s)
- Martin Obr
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Mathias Percipalle
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Darya Chernikova
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Huixin Yang
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
| | - Andreas Thader
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Gergely Pinke
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Dario Porley
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
| | - Louis M Mansky
- Institute for Molecular Virology, University of Minnesota, Minneapolis, MN, USA
| | - Robert A Dick
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA
| | - Florian KM Schur
- Institute of Science and Technology Austria (ISTA), Klosterneuburg, Austria
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11
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Kleinpeter AB, Zhu Y, Mallery DL, Ablan SD, Chen L, Hardenbrook N, Saiardi A, James LC, Zhang P, Freed EO. The Effect of Inositol Hexakisphosphate on HIV-1 Particle Production and Infectivity can be Modulated by Mutations that Affect the Stability of the Immature Gag Lattice. J Mol Biol 2023; 435:168037. [PMID: 37330292 PMCID: PMC10544863 DOI: 10.1016/j.jmb.2023.168037] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 06/19/2023]
Abstract
The assembly of an HIV-1 particle begins with the construction of a spherical lattice composed of hexamer subunits of the Gag polyprotein. The cellular metabolite inositol hexakisphosphate (IP6) binds and stabilizes the immature Gag lattice via an interaction with the six-helix bundle (6HB), a crucial structural feature of Gag hexamers that modulates both virus assembly and infectivity. The 6HB must be stable enough to promote immature Gag lattice formation, but also flexible enough to be accessible to the viral protease, which cleaves the 6HB during particle maturation. 6HB cleavage liberates the capsid (CA) domain of Gag from the adjacent spacer peptide 1 (SP1) and IP6 from its binding site. This pool of IP6 molecules then promotes the assembly of CA into the mature conical capsid that is required for infection. Depletion of IP6 in virus-producer cells results in severe defects in assembly and infectivity of wild-type (WT) virions. Here we show that in an SP1 double mutant (M4L/T8I) with a hyperstable 6HB, IP6 can block virion infectivity by preventing CA-SP1 processing. Thus, depletion of IP6 in virus-producer cells markedly increases M4L/T8I CA-SP1 processing and infectivity. We also show that the introduction of the M4L/T8I mutations partially rescues the assembly and infectivity defects induced by IP6 depletion on WT virions, likely by increasing the affinity of the immature lattice for limiting IP6. These findings reinforce the importance of the 6HB in virus assembly, maturation, and infection and highlight the ability of IP6 to modulate 6HB stability.
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Affiliation(s)
- Alex B Kleinpeter
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA. https://twitter.com/AlexKleinpeter
| | - Yanan Zhu
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Donna L Mallery
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Sherimay D Ablan
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Long Chen
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Nathan Hardenbrook
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Adolfo Saiardi
- Laboratory for Molecular Cell Biology, University College London, London, UK. https://twitter.com/SaiardiLab
| | - Leo C James
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK. https://twitter.com/JamesLab9
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK; Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford OX3 7BN, UK
| | - Eric O Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA.
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12
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Tao K, Rhee SY, Tzou PL, Osman ZA, Pond SLK, Holmes SP, Shafer RW. HIV-1 Group M Capsid Amino Acid Variability: Implications for Sequence Quality Control of Genotypic Resistance Testing. Viruses 2023; 15:992. [PMID: 37112972 PMCID: PMC10143361 DOI: 10.3390/v15040992] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/13/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
BACKGROUND With the approval of the HIV-1 capsid inhibitor, lenacapavir, capsid sequencing will be required for managing lenacapavir-experienced individuals with detectable viremia. Successful sequence interpretation will require examining new capsid sequences in the context of previously published sequence data. METHODS We analyzed published HIV-1 group M capsid sequences from 21,012 capsid-inhibitor naïve individuals to characterize amino acid variability at each position and influence of subtype and cytotoxic T lymphocyte (CTL) selection pressure. We determined the distributions of usual mutations, defined as amino acid differences from the group M consensus, with a prevalence ≥ 0.1%. Co-evolving mutations were identified using a phylogenetically-informed Bayesian graphical model method. RESULTS 162 (70.1%) positions had no usual mutations (45.9%) or only conservative usual mutations with a positive BLOSUM62 score (24.2%). Variability correlated independently with subtype-specific amino acid occurrence (Spearman rho = 0.83; p < 1 × 10-9) and the number of times positions were reported to contain an HLA-associated polymorphism, an indicator of CTL pressure (rho = 0.43; p = 0.0002). CONCLUSIONS Knowing the distribution of usual capsid mutations is essential for sequence quality control. Comparing capsid sequences from lenacapavir-treated and lenacapavir-naïve individuals will enable the identification of additional mutations potentially associated with lenacapavir therapy.
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Affiliation(s)
- Kaiming Tao
- Division of Infectious Diseases, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Soo-Yon Rhee
- Division of Infectious Diseases, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Philip L. Tzou
- Division of Infectious Diseases, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Zachary A. Osman
- Division of Infectious Diseases, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | | | - Susan P. Holmes
- Department of Statistics, Stanford University, Stanford, CA 94305, USA
| | - Robert W. Shafer
- Division of Infectious Diseases, Department of Medicine, Stanford University, Stanford, CA 94305, USA
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13
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Sarkar S, Zadrozny KK, Zadorozhnyi R, Russell RW, Quinn CM, Kleinpeter A, Ablan S, Meshkin H, Perilla JR, Freed EO, Ganser-Pornillos BK, Pornillos O, Gronenborn AM, Polenova T. Structural basis of HIV-1 maturation inhibitor binding and activity. Nat Commun 2023; 14:1237. [PMID: 36871077 PMCID: PMC9985623 DOI: 10.1038/s41467-023-36569-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 02/03/2023] [Indexed: 03/06/2023] Open
Abstract
HIV-1 maturation inhibitors (MIs), Bevirimat (BVM) and its analogs interfere with the catalytic cleavage of spacer peptide 1 (SP1) from the capsid protein C-terminal domain (CACTD), by binding to and stabilizing the CACTD-SP1 region. MIs are under development as alternative drugs to augment current antiretroviral therapies. Although promising, their mechanism of action and associated virus resistance pathways remain poorly understood at the molecular, biochemical, and structural levels. We report atomic-resolution magic-angle-spinning NMR structures of microcrystalline assemblies of CACTD-SP1 complexed with BVM and/or the assembly cofactor inositol hexakisphosphate (IP6). Our results reveal a mechanism by which BVM disrupts maturation, tightening the 6-helix bundle pore and quenching the motions of SP1 and the simultaneously bound IP6. In addition, BVM-resistant SP1-A1V and SP1-V7A variants exhibit distinct conformational and binding characteristics. Taken together, our study provides a structural explanation for BVM resistance as well as guidance for the design of new MIs.
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Affiliation(s)
- Sucharita Sarkar
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Kaneil K Zadrozny
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Roman Zadorozhnyi
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Ryan W Russell
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Caitlin M Quinn
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Alex Kleinpeter
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702-1201, USA
| | - Sherimay Ablan
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702-1201, USA
| | - Hamed Meshkin
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Juan R Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA
| | - Eric O Freed
- HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, 21702-1201, USA
| | - Barbie K Ganser-Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA.
| | - Owen Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA.
| | - Angela M Gronenborn
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
| | - Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, 15261, USA.
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14
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Lei X, Gonçalves-Carneiro D, Zang TM, Bieniasz PD. Initiation of HIV-1 Gag lattice assembly is required for recognition of the viral genome packaging signal. eLife 2023; 12:e83548. [PMID: 36688533 PMCID: PMC9908077 DOI: 10.7554/elife.83548] [Citation(s) in RCA: 4] [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: 09/18/2022] [Accepted: 01/20/2023] [Indexed: 01/24/2023] Open
Abstract
The encapsidation of HIV-1 gRNA into virions is enabled by the binding of the nucleocapsid (NC) domain of the HIV-1 Gag polyprotein to the structured viral RNA packaging signal (Ψ) at the 5' end of the viral genome. However, the subcellular location and oligomeric status of Gag during the initial Gag-Ψ encounter remain uncertain. Domains other than NC, such as capsid (CA), may therefore indirectly affect RNA recognition. To investigate the contribution of Gag domains to Ψ recognition in a cellular environment, we performed protein-protein crosslinking and protein-RNA crosslinking immunoprecipitation coupled with sequencing (CLIP-seq) experiments. We demonstrate that NC alone does not bind specifically to Ψ in living cells, whereas full-length Gag and a CANC subdomain bind to Ψ with high specificity. Perturbation of the Ψ RNA structure or NC zinc fingers affected CANC:Ψ binding specificity. Notably, CANC variants with substitutions that disrupt CA:CA dimer, trimer, or hexamer interfaces in the immature Gag lattice also affected RNA binding, and mutants that were unable to assemble a nascent Gag lattice were unable to specifically bind to Ψ. Artificially multimerized NC domains did not specifically bind Ψ. CA variants with substitutions in inositol phosphate coordinating residues that prevent CA hexamerization were also deficient in Ψ binding and second-site revertant mutants that restored CA assembly also restored specific binding to Ψ. Overall, these data indicate that the correct assembly of a nascent immature CA lattice is required for the specific interaction between Gag and Ψ in cells.
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Affiliation(s)
- Xiao Lei
- Laboratory of Retrovirology, Rockefeller UniversityNew YorkUnited States
| | | | - Trinity M Zang
- Laboratory of Retrovirology, Rockefeller UniversityNew YorkUnited States
- Howard Hughes Medical Institute, The Rockefeller UniversityNew York, New YorkUnited States
| | - Paul D Bieniasz
- Laboratory of Retrovirology, Rockefeller UniversityNew YorkUnited States
- Howard Hughes Medical Institute, The Rockefeller UniversityNew York, New YorkUnited States
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15
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Anti-HIV Potential of Beesioside I Derivatives as Maturation Inhibitors: Synthesis, 3D-QSAR, Molecular Docking and Molecular Dynamics Simulations. Int J Mol Sci 2023; 24:ijms24021430. [PMID: 36674943 PMCID: PMC9867151 DOI: 10.3390/ijms24021430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/04/2023] [Accepted: 01/09/2023] [Indexed: 01/13/2023] Open
Abstract
HIV-1 maturation is the final step in the retroviral lifecycle that is regulated by the proteolytic cleavage of the Gag precursor protein. As a first-in-class HIV-1 maturation inhibitor (MI), bevirimat blocks virion maturation by disrupting capsid-spacer peptide 1 (CA-SP1) cleavage, which acts as the target of MIs. Previous alterations of beesioside I (1) produced (20S,24S)-15ꞵ,16ꞵ-diacetoxy-18,24; 20,24-diepoxy-9,19-cyclolanostane-3ꞵ,25-diol 3-O-3′,3′-dimethylsuccinate (3, DSC), showing similar anti-HIV potency compared to bevirimat. To ascertain the binding modes of this derivative, further modification of compound 1 was conducted. Three-dimensional quantitative structure−activity relationship (3D-QSAR) analysis combined with docking simulations and molecular dynamics (MD) were conducted. Five new derivatives were synthesized, among which compound 3b showed significant activity against HIV-1NL4-3 with an EC50 value of 0.28 µM. The developed 3D-QSAR model resulted in great predictive ability with training set (r2 = 0.99, q2 = 0.55). Molecular docking studies were complementary to the 3D-QSAR analysis, showing that DSC was differently bound to CA-SP1 with higher affinity than that of bevirimat. MD studies revealed that the complex of the ligand and the protein was stable, with root mean square deviation (RMSD) values <2.5 Å. The above results provided valuable insights into the potential of DSC as a prototype to develop new antiviral agents.
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16
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Smith RA, Raugi DN, Nixon RS, Song J, Seydi M, Gottlieb GS, on behalf of the University of Washington-Senegal HIV-2 Study Group. Intrinsic resistance of HIV-2 and SIV to the maturation inhibitor GSK2838232. PLoS One 2023; 18:e0280568. [PMID: 36652466 PMCID: PMC9847912 DOI: 10.1371/journal.pone.0280568] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 01/02/2023] [Indexed: 01/19/2023] Open
Abstract
GSK2838232 (GSK232) is a novel maturation inhibitor that blocks the proteolytic cleavage of HIV-1 Gag at the junction of capsid and spacer peptide 1 (CA/SP1), rendering newly-formed virions non-infectious. To our knowledge, GSK232 has not been tested against HIV-2, and there are limited data regarding the susceptibility of HIV-2 to other HIV-1 maturation inhibitors. To assess the potential utility of GSK232 as an option for HIV-2 treatment, we determined the activity of the compound against a panel of HIV-1, HIV-2, and SIV isolates in culture. GSK232 was highly active against HIV-1 isolates from group M subtypes A, B, C, D, F, and group O, with IC50 values ranging from 0.25-0.92 nM in spreading (multi-cycle) assays and 1.5-2.8 nM in a single cycle of infection. In contrast, HIV-2 isolates from groups A, B, and CRF01_AB, and SIV isolates SIVmac239, SIVmac251, and SIVagm.sab-2, were highly resistant to GSK232. To determine the role of CA/SP1 in the observed phenotypes, we constructed a mutant of HIV-2ROD9 in which the sequence of CA/SP1 was modified to match the corresponding sequence found in HIV-1. The resulting variant was fully susceptible to GSK232 in the single-cycle assay (IC50 = 1.8 nM). Collectively, our data indicate that the HIV-2 and SIV isolates tested in our study are intrinsically resistant to GSK232, and that the determinants of resistance map to CA/SP1. The molecular mechanism(s) responsible for the differential susceptibility of HIV-1 and HIV-2/SIV to GSK232 require further investigation.
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Affiliation(s)
- Robert A. Smith
- Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- * E-mail:
| | - Dana N. Raugi
- Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Robert S. Nixon
- Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Jennifer Song
- Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
| | - Moussa Seydi
- Service des Maladies Infectieuses et Tropicales, CHNU de Fann, Dakar, Senegal
| | - Geoffrey S. Gottlieb
- Center for Emerging and Reemerging Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
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17
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Hartz RA, Xu L, Sit SY, Chen J, Venables BL, Lin Z, Zhang S, Li Z, Parker D, Simmons TS, Jenkins S, Hanumegowda UM, Dicker I, Krystal M, Meanwell NA, Regueiro-Ren A. Synthesis, Structure-Activity Relationships, and In Vivo Evaluation of Novel C-17 Amine Derivatives Based on GSK3640254 as HIV-1 Maturation Inhibitors with Broad Spectrum Activity. J Med Chem 2022; 65:15935-15966. [PMID: 36441509 DOI: 10.1021/acs.jmedchem.2c01618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An investigation of the structure-activity relationships of a series of HIV-1 maturation inhibitors (MIs) based on GSK3640254 (4) was conducted by incorporating novel C-17 amine substituents to reduce the overall basicity of the resultant analogues. We found that replacement of the distal amine on the C-17 sidechain present in 4 with a tertiary alcohol in combination with either a heterocyclic ring system or a cyclohexyl ring substituted with polar groups provided potent wild-type HIV-1 MIs that also retained excellent potency against a T332S/V362I/prR41G variant, a laboratory strain that served as a surrogate to assess HIV-1 polymorphic virus coverage. Compound 26 exhibited broad-spectrum HIV-1 activity against an expanded panel of clinically relevant Gag polymorphic viruses and had the most desirable overall profile in this series of compounds. In pharmacokinetic studies, 26 had low clearance and exhibited 24 and 31% oral bioavailability in rats and dogs, respectively.
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Affiliation(s)
- Richard A Hartz
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Li Xu
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Sing-Yuen Sit
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Jie Chen
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Brian L Venables
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Zeyu Lin
- Department of Virology, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Sharon Zhang
- Department of Virology, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Zhufang Li
- Department of Virology, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Dawn Parker
- Department of Metabolism and Pharmacokinetics, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Tara S Simmons
- Department of Metabolism and Pharmacokinetics, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Susan Jenkins
- Department of Metabolism and Pharmacokinetics, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Umesh M Hanumegowda
- Department of Metabolism and Pharmacokinetics, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Ira Dicker
- Department of Virology, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Mark Krystal
- Department of Virology, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Nicholas A Meanwell
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Alicia Regueiro-Ren
- Department of Small Molecule Drug Discovery, Bristol Myers Squibb, Research and Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
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18
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Regueiro-Ren A, Sit SY, Chen Y, Chen J, Swidorski JJ, Liu Z, Venables BL, Sin N, Hartz RA, Protack T, Lin Z, Zhang S, Li Z, Wu DR, Li P, Kempson J, Hou X, Gupta A, Rampulla R, Mathur A, Park H, Sarjeant A, Benitex Y, Rahematpura S, Parker D, Phillips T, Haskell R, Jenkins S, Santone KS, Cockett M, Hanumegowda U, Dicker I, Meanwell NA, Krystal M. The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV-1 Maturation. J Med Chem 2022; 65:11927-11948. [PMID: 36044257 DOI: 10.1021/acs.jmedchem.2c00879] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity toward the second-generation MI GSK3532795 (BMS-955176). The key structural difference between GSK3640254 and its predecessor is the replacement of the para-substituted benzoic acid moiety attached at the C-3 position of the triterpenoid core with a cyclohex-3-ene-1-carboxylic acid substituted with a CH2F moiety at the carbon atom α- to the pharmacophoric carboxylic acid. This structural element provided a new vector with which to explore structure-activity relationships (SARs) and led to compounds with improved polymorphic coverage while preserving pharmacokinetic (PK) properties. The approach to the design of GSK3640254, the development of a synthetic route and its preclinical profile are discussed. GSK3640254 is currently in phase IIb clinical trials after demonstrating a dose-related reduction in HIV-1 viral load over 7-10 days of dosing to HIV-1-infected subjects.
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Affiliation(s)
- Alicia Regueiro-Ren
- Small Molecule Drug Discovery, Bristol Myers Squibb Research and Early Development, Princeton, New Jersey08543, United States
| | - Sing-Yuen Sit
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Yan Chen
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Jie Chen
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Jacob J Swidorski
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Zheng Liu
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Brian L Venables
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Ny Sin
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Richard A Hartz
- Department of Discovery Chemistry, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Tricia Protack
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Zeyu Lin
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Sharon Zhang
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Zhufang Li
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Dauh-Rurng Wu
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - Peng Li
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - James Kempson
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - Xiaoping Hou
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - Anuradha Gupta
- Department of Discovery Synthesis; Bristol Myers Squibb Research and Early Development, Bangalore 560099, India
| | - Richard Rampulla
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - Arvind Mathur
- Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, PO Box 4000, Princeton, New Jersey08543, United States
| | - Hyunsoo Park
- Bristol Myers Squibb Chemical and Synthetic Development, New Brunswick, New Jersey08901, United States
| | - Amy Sarjeant
- Bristol Myers Squibb Chemical and Synthetic Development, New Brunswick, New Jersey08901, United States
| | - Yulia Benitex
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Sandhya Rahematpura
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Dawn Parker
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Thomas Phillips
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Roy Haskell
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Susan Jenkins
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Kenneth S Santone
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Mark Cockett
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Umesh Hanumegowda
- Department of Pharmaceutical Candidate Optimization, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Ira Dicker
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
| | - Nicholas A Meanwell
- Small Molecule Drug Discovery, Bristol Myers Squibb Research and Early Development, Princeton, New Jersey08543, United States
| | - Mark Krystal
- Department of Virology, Bristol Myers Squibb Research and Early Development, 5 Research Parkway, Wallingford, Connecticut06492, United States
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19
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Pak A, Gupta M, Yeager M, Voth GA. Inositol Hexakisphosphate (IP6) Accelerates Immature HIV-1 Gag Protein Assembly toward Kinetically Trapped Morphologies. J Am Chem Soc 2022; 144:10417-10428. [PMID: 35666943 PMCID: PMC9204763 DOI: 10.1021/jacs.2c02568] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
During the late stages of the HIV-1 lifecycle, immature virions are produced by the concerted activity of Gag polyproteins, primarily mediated by the capsid (CA) and spacer peptide 1 (SP1) domains, which assemble into a spherical lattice, package viral genomic RNA, and deform the plasma membrane. Recently, inositol hexakisphosphate (IP6) has been identified as an essential assembly cofactor that efficiently produces both immature virions in vivo and immature virus-like particles in vitro. To date, however, several distinct mechanistic roles for IP6 have been proposed on the basis of independent functional, structural, and kinetic studies. In this work, we investigate the molecular influence of IP6 on the structural outcomes and dynamics of CA/SP1 assembly using coarse-grained (CG) molecular dynamics (MD) simulations and free energy calculations. Here, we derive a bottom-up, low-resolution, and implicit-solvent CG model of CA/SP1 and IP6, and simulate their assembly under conditions that emulate both in vitro and in vivo systems. Our analysis identifies IP6 as an assembly accelerant that promotes curvature generation and fissure-like defects throughout the lattice. Our findings suggest that IP6 induces kinetically trapped immature morphologies, which may be physiologically important for later stages of viral morphogenesis and potentially useful for virus-like particle technologies.
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Affiliation(s)
- Alexander
J. Pak
- Department
of Chemistry, Chicago Center for Theoretical Chemistry, Institute
for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Manish Gupta
- Department
of Chemistry, Chicago Center for Theoretical Chemistry, Institute
for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Mark Yeager
- Department
of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States,Center
for Membrane Biology, University of Virginia
School of Medicine, Charlottesville, Virginia 22908, United States, United States,Cardiovascular
Research Center, University of Virginia
School of Medicine, Charlottesville, Virginia 22908, United States,Department
of Medicine, Division of Cardiovascular Medicine, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States
| | - Gregory A. Voth
- Department
of Chemistry, Chicago Center for Theoretical Chemistry, Institute
for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States,E-mail:
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20
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Sumner C, Ono A. Relationship between HIV-1 Gag Multimerization and Membrane Binding. Viruses 2022; 14:v14030622. [PMID: 35337029 PMCID: PMC8949992 DOI: 10.3390/v14030622] [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: 01/19/2022] [Revised: 03/06/2022] [Accepted: 03/09/2022] [Indexed: 12/11/2022] Open
Abstract
HIV-1 viral particle assembly occurs specifically at the plasma membrane and is driven primarily by the viral polyprotein Gag. Selective association of Gag with the plasma membrane is a key step in the viral assembly pathway, which is traditionally attributed to the MA domain. MA regulates specific plasma membrane binding through two primary mechanisms including: (1) specific interaction of the MA highly basic region (HBR) with the plasma membrane phospholipid phosphatidylinositol (4,5) bisphosphate [PI(4,5)P2], and (2) tRNA binding to the MA HBR, which prevents Gag association with non-PI(4,5)P2 containing membranes. Gag multimerization, driven by both CA–CA inter-protein interactions and NC-RNA binding, also plays an essential role in viral particle assembly, mediating the establishment and growth of the immature Gag lattice on the plasma membrane. In addition to these functions, the multimerization of HIV-1 Gag has also been demonstrated to enhance its membrane binding activity through the MA domain. This review provides an overview of the mechanisms regulating Gag membrane binding through the MA domain and multimerization through the CA and NC domains, and examines how these two functions are intertwined, allowing for multimerization mediated enhancement of Gag membrane binding.
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21
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Lerner G, Weaver N, Anokhin B, Spearman P. Advances in HIV-1 Assembly. Viruses 2022; 14:v14030478. [PMID: 35336885 PMCID: PMC8952333 DOI: 10.3390/v14030478] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 12/10/2022] Open
Abstract
The assembly of HIV-1 particles is a concerted and dynamic process that takes place on the plasma membrane of infected cells. An abundance of recent discoveries has advanced our understanding of the complex sequence of events leading to HIV-1 particle assembly, budding, and release. Structural studies have illuminated key features of assembly and maturation, including the dramatic structural transition that occurs between the immature Gag lattice and the formation of the mature viral capsid core. The critical role of inositol hexakisphosphate (IP6) in the assembly of both the immature and mature Gag lattice has been elucidated. The structural basis for selective packaging of genomic RNA into virions has been revealed. This review will provide an overview of the HIV-1 assembly process, with a focus on recent advances in the field, and will point out areas where questions remain that can benefit from future investigation.
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22
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Zurowska K, Alam A, Ganser-Pornillos BK, Pornillos O. Structural evidence that MOAP1 and PEG10 are derived from retrovirus/retrotransposon Gag proteins. Proteins 2022; 90:309-313. [PMID: 34357660 PMCID: PMC8671222 DOI: 10.1002/prot.26204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 07/06/2021] [Accepted: 07/28/2021] [Indexed: 01/03/2023]
Abstract
The Gag proteins of retroviruses play an essential role in virus particle assembly by forming a protein shell or capsid and thus generating the virion compartment. A variety of human proteins have now been identified with structural similarity to one or more of the major Gag domains. These human proteins are thought to have been evolved or "domesticated" from ancient integrations due to retroviral infections or retrotransposons. Here, we report that X-ray crystal structures of stably folded domains of MOAP1 (modulator of apoptosis 1) and PEG10 (paternally expressed gene 10) are highly similar to the C-terminal capsid (CA) domains of cognate Gag proteins. The structures confirm classification of MOAP1 and PEG10 as domesticated Gags, and suggest that these proteins may have preserved some of the key interactions that facilitated assembly of their ancestral Gags into capsids.
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Affiliation(s)
- Katarzyna Zurowska
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Ayaan Alam
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Barbie K Ganser-Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
| | - Owen Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia, USA
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23
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Krebs AS, Mendonça LM, Zhang P. Structural Analysis of Retrovirus Assembly and Maturation. Viruses 2021; 14:54. [PMID: 35062258 PMCID: PMC8778513 DOI: 10.3390/v14010054] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 12/30/2022] Open
Abstract
Retroviruses have a very complex and tightly controlled life cycle which has been studied intensely for decades. After a virus enters the cell, it reverse-transcribes its genome, which is then integrated into the host genome, and subsequently all structural and regulatory proteins are transcribed and translated. The proteins, along with the viral genome, assemble into a new virion, which buds off the host cell and matures into a newly infectious virion. If any one of these steps are faulty, the virus cannot produce infectious viral progeny. Recent advances in structural and molecular techniques have made it possible to better understand this class of viruses, including details about how they regulate and coordinate the different steps of the virus life cycle. In this review we summarize the molecular analysis of the assembly and maturation steps of the life cycle by providing an overview on structural and biochemical studies to understand these processes. We also outline the differences between various retrovirus families with regards to these processes.
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Affiliation(s)
- Anna-Sophia Krebs
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.-S.K.); (L.M.M.)
| | - Luiza M. Mendonça
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.-S.K.); (L.M.M.)
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (A.-S.K.); (L.M.M.)
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford OX3 7BN, UK
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24
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McFadden WM, Snyder AA, Kirby KA, Tedbury PR, Raj M, Wang Z, Sarafianos SG. Rotten to the core: antivirals targeting the HIV-1 capsid core. Retrovirology 2021; 18:41. [PMID: 34937567 PMCID: PMC8693499 DOI: 10.1186/s12977-021-00583-z] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 11/09/2021] [Indexed: 12/20/2022] Open
Abstract
The capsid core of HIV-1 is a large macromolecular assembly that surrounds the viral genome and is an essential component of the infectious virus. In addition to its multiple roles throughout the viral life cycle, the capsid interacts with multiple host factors. Owing to its indispensable nature, the HIV-1 capsid has been the target of numerous antiretrovirals, though most capsid-targeting molecules have not had clinical success until recently. Lenacapavir, a long-acting drug that targets the HIV-1 capsid, is currently undergoing phase 2/3 clinical trials, making it the most successful capsid inhibitor to-date. In this review, we detail the role of the HIV-1 capsid protein in the virus life cycle, categorize antiviral compounds based on their targeting of five sites within the HIV-1 capsid, and discuss their molecular interactions and mechanisms of action. The diverse range of inhibition mechanisms provides insight into possible new strategies for designing novel HIV-1 drugs and furthers our understanding of HIV-1 biology. ![]()
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Affiliation(s)
- William M McFadden
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Alexa A Snyder
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Karen A Kirby
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Philip R Tedbury
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Monika Raj
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA.
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25
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Plasma Membrane Anchoring and Gag:Gag Multimerization on Viral RNA Are Critical Properties of HIV-1 Gag Required To Mediate Efficient Genome Packaging. mBio 2021; 12:e0325421. [PMID: 34872357 PMCID: PMC8649766 DOI: 10.1128/mbio.03254-21] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) Gag selects and packages the HIV RNA genome during virus assembly. However, HIV-1 RNA constitutes only a small fraction of the cellular RNA. Although Gag exhibits a slight preference to viral RNA, most of the cytoplasmic Gag proteins are associated with cellular RNAs. Thus, it is not understood how HIV-1 achieves highly efficient genome packaging. We hypothesize that besides RNA binding, other properties of Gag are important for genome packaging. Many Gag mutants have assembly defects that preclude analysis of their effects on genome packaging. To bypass this challenge, we established complementation systems that separate the particle-assembling and RNA-binding functions of Gag: we used a set of Gag proteins to drive particle assembly and an RNA-binding Gag to package HIV-1 RNA. We have developed two types of RNA-binding Gag in which packaging is mediated by the authentic nucleocapsid (NC) domain or by a nonviral RNA-binding domain. We found that in both cases, mutations that affect the multimerization or plasma membrane anchoring properties of Gag reduce or abolish RNA packaging. These mutant Gag can coassemble into particles but cannot package the RNA genome efficiently. Our findings indicate that HIV-1 RNA packaging occurs at the plasma membrane and RNA-binding Gag needs to multimerize on RNA to encapsidate the viral genome.
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26
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Zhang X, Sun L, Meuser ME, Zalloum WA, Xu S, Huang T, Cherukupalli S, Jiang X, Ding X, Tao Y, Kang D, De Clercq E, Pannecouque C, Dick A, Cocklin S, Liu X, Zhan P. Design, synthesis, and mechanism study of dimerized phenylalanine derivatives as novel HIV-1 capsid inhibitors. Eur J Med Chem 2021; 226:113848. [PMID: 34592608 DOI: 10.1016/j.ejmech.2021.113848] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/02/2021] [Accepted: 09/09/2021] [Indexed: 12/16/2022]
Abstract
HIV-1 capsid (CA) plays indispensable and multiple roles in the life cycle of HIV-1, become an attractive target in antiviral therapy. Herein, we report the design, synthesis, and mechanism study of a novel series of dimerized phenylalanine derivatives as HIV-1 capsid inhibitors using 2-piperazineone or 2,5-piperazinedione as a linker. The structure-activity relationship (SAR) indicated that dimerized phenylalanines were more potent than monomers of the same chemotype. Further, the inclusion of fluorine substituted phenylalanine and methoxyl substituted aniline was found to be beneficial for antiviral activity. From the synthesized series, Q-c4 was found to be the most potent compound with an EC50 value of 0.57 μM, comparable to PF74. Interestingly, Q-c4 demonstrated a slightly higher affinity to the CA monomer than the CA hexamer, commensurate with its more significant effect in the late-stage of the HIV-1 lifecycle. Competitive SPR experiments with peptides from CPSF6 and NUP153 revealed that Q-c4 binds to the interprotomer pocket of hexameric CA as designed. Single-round infection assays showed that Q-c4 interferes with the HIV-1 life cycle in a dual-stage manner, affecting both pre-and post-integration. Stability assays in human plasma and human liver microsomes indicated that although Q-c4 has improved stability over PF74, this kind of inhibitor still requires further optimization. And the results of the online molinspiration software predicted that Q-c4 has desirable physicochemical properties but some properties still have some violation from the Lipinski rule of five. Overall, the dimerized phenylalanines are promising novel platforms for developing future HIV-1 CA inhibitors with considerable potential for optimization.
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Affiliation(s)
- Xujie Zhang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Lin Sun
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Megan E Meuser
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA
| | - Waleed A Zalloum
- Department of Pharmacy, Faculty of Health Science, American University of Madaba, P.O Box 2882, Amman, 11821, Jordan
| | - Shujing Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Tianguang Huang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Srinivasulu Cherukupalli
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Xiangyi Jiang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Xiao Ding
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Yucen Tao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Dongwei Kang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Erik De Clercq
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U. Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium
| | - Christophe Pannecouque
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U. Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium.
| | - Alexej Dick
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA.
| | - Simon Cocklin
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, 19102, USA.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology, Ministry of Education, School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
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27
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Zadorozhnyi R, Sarkar S, Quinn CM, Zadrozny KK, Ganser-Pornillos BK, Pornillos O, Gronenborn AM, Polenova T. Determination of Histidine Protonation States in Proteins by Fast Magic Angle Spinning NMR. Front Mol Biosci 2021; 8:767040. [PMID: 34957215 PMCID: PMC8703106 DOI: 10.3389/fmolb.2021.767040] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/15/2021] [Indexed: 12/29/2022] Open
Abstract
Histidine residues play important structural and functional roles in proteins, such as serving as metal-binding ligands, mediating enzyme catalysis, and modulating proton channel activity. Many of these activities are modulated by the ionization state of the imidazole ring. Here we present a fast MAS NMR approach for the determination of protonation and tautomeric states of His at frequencies of 40-62 kHz. The experiments combine 1H detection with selective magnetization inversion techniques and transferred echo double resonance (TEDOR)-based filters, in 2D heteronuclear correlation experiments. We illustrate this approach using microcrystalline assemblies of HIV-1 CACTD-SP1 protein.
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Affiliation(s)
- Roman Zadorozhnyi
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, United States
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Sucharita Sarkar
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, United States
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Caitlin M. Quinn
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, United States
| | - Kaneil K. Zadrozny
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Barbie K. Ganser-Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Owen Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Angela M. Gronenborn
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, United States
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
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28
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Ni T, Zhu Y, Yang Z, Xu C, Chaban Y, Nesterova T, Ning J, Böcking T, Parker MW, Monnie C, Ahn J, Perilla JR, Zhang P. Structure of native HIV-1 cores and their interactions with IP6 and CypA. SCIENCE ADVANCES 2021; 7:eabj5715. [PMID: 34797722 PMCID: PMC8604400 DOI: 10.1126/sciadv.abj5715] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 10/01/2021] [Indexed: 05/24/2023]
Abstract
The viral capsid plays essential roles in HIV replication and is a major platform engaging host factors. To overcome challenges in study native capsid structure, we used the perfringolysin O to perforate the membrane of HIV-1 particles, thus allowing host proteins and small molecules to access the native capsid while improving cryo–electron microscopy image quality. Using cryo–electron tomography and subtomogram averaging, we determined the structures of native capsomers in the presence and absence of inositol hexakisphosphate (IP6) and cyclophilin A and constructed an all-atom model of a complete HIV-1 capsid. Our structures reveal two IP6 binding sites and modes of cyclophilin A interactions. Free energy calculations substantiate the two binding sites at R18 and K25 and further show a prohibitive energy barrier for IP6 to pass through the pentamer. Our results demonstrate that perfringolysin O perforation is a valuable tool for structural analyses of enveloped virus capsids and interactions with host cell factors.
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Affiliation(s)
- Tao Ni
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Yanan Zhu
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Zhengyi Yang
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Chaoyi Xu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Yuriy Chaban
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
| | - Tanya Nesterova
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Jiying Ning
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Till Böcking
- EMBL Australia Node in Single Molecule Science and ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, UNSW, Sydney, Australia
| | - Michael W. Parker
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
- St. Vincent’s Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Christina Monnie
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jinwoo Ahn
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Juan R. Perilla
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, USA
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
- Chinese Academy of Medical Sciences Oxford Institute, University of Oxford, Oxford OX3 7BN, UK
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29
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Pak AJ, Purdy MD, Yeager M, Voth GA. Preservation of HIV-1 Gag Helical Bundle Symmetry by Bevirimat Is Central to Maturation Inhibition. J Am Chem Soc 2021; 143:19137-19148. [PMID: 34739240 DOI: 10.1021/jacs.1c08922] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The assembly and maturation of human immunodeficiency virus type 1 (HIV-1) require proteolytic cleavage of the Gag polyprotein. The rate-limiting step resides at the junction between the capsid protein CA and spacer peptide 1, which assembles as a six-helix bundle (6HB). Bevirimat (BVM), the first-in-class maturation inhibitor drug, targets the 6HB and impedes proteolytic cleavage, yet the molecular mechanisms of its activity, and relatedly, the escape mechanisms of mutant viruses, remain unclear. Here, we employed extensive molecular dynamics (MD) simulations and free energy calculations to quantitatively investigate molecular structure-activity relationships, comparing wild-type and mutant viruses in the presence and absence of BVM and inositol hexakisphosphate (IP6), an assembly cofactor. Our analysis shows that the efficacy of BVM is directly correlated with preservation of 6-fold symmetry in the 6HB, which exists as an ensemble of structural states. We identified two primary escape mechanisms, and both lead to loss of symmetry, thereby facilitating helix uncoiling to aid access of protease. Our findings also highlight specific interactions that can be targeted for improved inhibitor activity and support the use of MD simulations for future inhibitor design.
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Affiliation(s)
- Alexander J Pak
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Michael D Purdy
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States
| | - Mark Yeager
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States.,Center for Membrane Biology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States.,Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States.,Department of Medicine, Division of Cardiovascular Medicine, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
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30
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Stephan Oroszlan and the Proteolytic Processing of Retroviral Proteins: Following A Pro. Viruses 2021; 13:v13112218. [PMID: 34835024 PMCID: PMC8621278 DOI: 10.3390/v13112218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 12/26/2022] Open
Abstract
Steve Oroszlan determined the sequences at the ends of virion proteins for a number of different retroviruses. This work led to the insight that the amino-terminal amino acid of the mature viral CA protein is always proline. In this remembrance, we review Steve’s work that led to this insight and show how that insight was a necessary precursor to the work we have done in the subsequent years exploring the cleavage rate determinants of viral protease processing sites and the multiple roles the amino-terminal proline of CA plays after protease cleavage liberates it from its position in a protease processing site.
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31
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Saito A, Yamashita M. HIV-1 capsid variability: viral exploitation and evasion of capsid-binding molecules. Retrovirology 2021; 18:32. [PMID: 34702294 PMCID: PMC8549334 DOI: 10.1186/s12977-021-00577-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 10/13/2021] [Indexed: 11/17/2022] Open
Abstract
The HIV-1 capsid, a conical shell encasing viral nucleoprotein complexes, is involved in multiple post-entry processes during viral replication. Many host factors can directly bind to the HIV-1 capsid protein (CA) and either promote or prevent HIV-1 infection. The viral capsid is currently being explored as a novel target for therapeutic interventions. In the past few decades, significant progress has been made in our understanding of the capsid–host interactions and mechanisms of action of capsid-targeting antivirals. At the same time, a large number of different viral capsids, which derive from many HIV-1 mutants, naturally occurring variants, or diverse lentiviruses, have been characterized for their interactions with capsid-binding molecules in great detail utilizing various experimental techniques. This review provides an overview of how sequence variation in CA influences phenotypic properties of HIV-1. We will focus on sequence differences that alter capsid–host interactions and give a brief account of drug resistant mutations in CA and their mutational effects on viral phenotypes. Increased knowledge of the sequence-function relationship of CA helps us deepen our understanding of the adaptive potential of the viral capsid.
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Affiliation(s)
- Akatsuki Saito
- Department of Veterinary Medicine, Faculty of Agriculture, University of Miyazaki, Miyazaki, Miyazaki, Japan.,Center for Animal Disease Control, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Masahiro Yamashita
- Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, USA.
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32
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Xu S, Sun L, Dick A, Zalloum WA, Huang T, Meuser ME, Zhang X, Tao Y, Cherukupalli S, Ding D, Ding X, Gao S, Jiang X, Kang D, De Clercq E, Pannecouque C, Cocklin S, Liu X, Zhan P. Design, synthesis, and mechanistic investigations of phenylalanine derivatives containing a benzothiazole moiety as HIV-1 capsid inhibitors with improved metabolic stability. Eur J Med Chem 2021; 227:113903. [PMID: 34653770 DOI: 10.1016/j.ejmech.2021.113903] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/03/2021] [Accepted: 10/03/2021] [Indexed: 12/17/2022]
Abstract
Further clinical development of PF74, a lead compound targeting HIV-1 capsid, is impeded by low antiviral activity and inferior metabolic stability. By modifying the benzene (region I) and indole of PF74, we identified two potent compounds (7m and 7u) with significantly improved metabolic stability. Compared to PF74, 7u displayed greater metabolic stability in human liver microsomes (HLMs) with half-life (t1/2) 109-fold that of PF74. Moreover, mechanism of action (MOA) studies demonstrated that 7m and 7u effectively mirrored the MOA of compounds that interact within the PF74 interprotomer pocket, showing direct and robust interactions with recombinant CA, and 7u displaying antiviral effects in both the early and late stages of HIV-1 replication. Furthermore, MD simulation corroborated that 7u was bound to the PF74 binding site, and the results of the online molinspiration software predicted that 7m and 7u had desirable physicochemical properties. Unexpectedly, this series of compounds exhibited better antiviral activity than PF74 against HIV-2, represented by compound 7m whose anti-HIV-2 activity was almost 5 times increased potency over PF74. Therefore, we have rationally redesigned the PF74 chemotype to inhibitors with novel structures and enhanced metabolic stability in this study. We hope that these new compounds can serve as a blueprint for developing a new generation of HIV treatment regimens.
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Affiliation(s)
- Shujing Xu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Lin Sun
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Alexej Dick
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, PA, 19102, USA
| | - Waleed A Zalloum
- Department of Pharmacy, Faculty of Health Science, American University of Madaba, P.O Box 2882, Amman, 11821, Jordan
| | - Tianguang Huang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Megan E Meuser
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, PA, 19102, USA
| | - Xujie Zhang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Yucen Tao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Srinivasulu Cherukupalli
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Dang Ding
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Xiao Ding
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Shenghua Gao
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Xiangyi Jiang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Dongwei Kang
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China
| | - Erik De Clercq
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U. Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium
| | - Christophe Pannecouque
- Rega Institute for Medical Research, Laboratory of Virology and Chemotherapy, K.U. Leuven, Herestraat 49 Postbus 1043 (09.A097), B-3000, Leuven, Belgium.
| | - Simon Cocklin
- Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, Philadelphia, PA, PA, 19102, USA.
| | - Xinyong Liu
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
| | - Peng Zhan
- Department of Medicinal Chemistry, Key Laboratory of Chemical Biology (Ministry of Education), School of Pharmaceutical Sciences, Shandong University, 44 West Culture Road, 250012, Jinan, Shandong, PR China.
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33
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Chen X, Coric P, Bouaziz S. 1H, 13C and 15N backbone resonance assignment of HIV-1 Gag (276-432) encompassing the C-terminal domain of the capsid protein, the spacer peptide 1 and the nucleocapsid protein. BIOMOLECULAR NMR ASSIGNMENTS 2021; 15:267-271. [PMID: 33754285 DOI: 10.1007/s12104-021-10016-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
During the maturation of the HIV-1 particle, the Gag polyprotein is cleaved by the viral protease into several proteins: matrix (MA), capsid (CA), spacer peptide 1 (SP1), nucleocapsid (NC), spacer peptide 2 (SP2) and p6. After cleavage, these proteins rearrange to form infectious viral particles. The final cleavage by the protease occurs between CA and SP1 and is the limiting step for the maturation of the particle. The CA-SP1 junction is the target of HIV-1 maturation inhibitors. CA is responsible for the formation of the viral capsid which protects the viral RNA inside. The SP1 domain is essential for viral assembly and infectivity, it is flexible and in helix-coil equilibrium. The presence of NC allows the SP1 domain to be less dynamic. The perturbation of the natural coil-helix equilibrium to helix interferes with protease cleavage and leads to non-completion of viral maturation. In this work, two mutations, W316A and M317A, that abolish the oligomerization of CA were introduced into the protein. The HIV-1 CACTDW316A, M317A-SP1-NC which contains the C-terminal monomeric mutant of CA, SP1 and NC was produced to study the mechanism of action of HIV-1 maturation inhibitors. Here we report the backbone assignment of the protein CACTDW316A, M317A-SP1-NC. These results will be useful to study the interaction between HIV-1 Gag and HIV-1 maturation inhibitors.
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Affiliation(s)
- Xiaowei Chen
- CiTCoM, CNRS, UMR 8038, Université de Paris, Paris, France
| | - Pascale Coric
- CiTCoM, CNRS, UMR 8038, Université de Paris, Paris, France
| | - Serge Bouaziz
- CiTCoM, CNRS, UMR 8038, Université de Paris, Paris, France.
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34
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Saha I, Preece B, Peterson A, Durden H, MacArthur B, Lowe J, Belnap D, Vershinin M, Saffarian S. Gag-Gag Interactions Are Insufficient to Fully Stabilize and Order the Immature HIV Gag Lattice. Viruses 2021; 13:1946. [PMID: 34696376 PMCID: PMC8540168 DOI: 10.3390/v13101946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 11/16/2022] Open
Abstract
Immature HIV virions harbor a lattice of Gag molecules with significant ordering in CA-NTD, CA-CTD and SP1 regions. This ordering plays a major role during HIV maturation. To test the condition in which the Gag lattice forms in vivo, we assembled virus like particles (VLPs) by expressing only HIV Gag in mammalian cells. Here we show that these VLPs incorporate a similar number of Gag molecules compared to immature HIV virions. However, within these VLPs, Gag molecules diffuse with a pseudo-diffusion rate of 10 nm2/s, this pseudo-diffusion is abrogated in the presence of melittin and is sensitive to mutations within the SP1 region. Using cryotomography, we show that unlike immature HIV virions, in the Gag lattice of VLPs the CA-CTD and SP1 regions are significantly less ordered. Our observations suggest that within immature HIV virions, other viral factors in addition to Gag, contribute to ordering in the CA-CTD and SP1 regions.
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Affiliation(s)
- Ipsita Saha
- Laboratory of Cell and Developmental Signaling, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA;
| | - Benjamin Preece
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Abby Peterson
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Haley Durden
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Brian MacArthur
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Jake Lowe
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA; (J.L.); (D.B.)
| | - David Belnap
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA; (J.L.); (D.B.)
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA
| | - Michael Vershinin
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA; (J.L.); (D.B.)
| | - Saveez Saffarian
- Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, USA; (B.P.); (A.P.); (H.D.); (B.M.); (M.V.)
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA; (J.L.); (D.B.)
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35
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Das M, Chen N, LiWang A, Wang LP. Identification and characterization of metamorphic proteins: Current and future perspectives. Biopolymers 2021; 112:e23473. [PMID: 34528703 DOI: 10.1002/bip.23473] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 11/06/2022]
Abstract
Proteins that can reversibly alternate between distinctly different folds under native conditions are described as being metamorphic. The "metamorphome" is the collection of all metamorphic proteins in the proteome, but it remains unknown the extent to which the proteome is populated by this class of proteins. We propose that uncovering the metamorphome will require a synergy of computational screening of protein sequences to identify potential metamorphic behavior and validation through experimental techniques. This perspective discusses computational and experimental approaches that are currently used to predict and characterize metamorphic proteins as well as the need for developing improved methodologies. Since metamorphic proteins act as molecular switches, understanding their properties and behavior could lead to novel applications of these proteins as sensors in biological or environmental contexts.
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Affiliation(s)
- Madhurima Das
- School of Natural Sciences, University of California, Merced, California, USA
| | - Nanhao Chen
- Department of Chemistry, University of California, Davis, California, USA
| | - Andy LiWang
- School of Natural Sciences, University of California, Merced, California, USA.,Department of Chemistry and Biochemistry, University of California, Merced, California, USA.,Center for Cellular and Biomolecular Machines, University of California, Merced, California, USA.,Health Sciences Research Institute, University of California, Merced, California, USA.,Center for Circadian Biology, University of California, San Diego, California, USA
| | - Lee-Ping Wang
- Department of Chemistry, University of California, Davis, California, USA
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36
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Obr M, Schur FKM, Dick RA. A Structural Perspective of the Role of IP6 in Immature and Mature Retroviral Assembly. Viruses 2021; 13:1853. [PMID: 34578434 PMCID: PMC8473085 DOI: 10.3390/v13091853] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 11/17/2022] Open
Abstract
The small cellular molecule inositol hexakisphosphate (IP6) has been known for ~20 years to promote the in vitro assembly of HIV-1 into immature virus-like particles. However, the molecular details underlying this effect have been determined only recently, with the identification of the IP6 binding site in the immature Gag lattice. IP6 also promotes formation of the mature capsid protein (CA) lattice via a second IP6 binding site, and enhances core stability, creating a favorable environment for reverse transcription. IP6 also enhances assembly of other retroviruses, from both the Lentivirus and the Alpharetrovirus genera. These findings suggest that IP6 may have a conserved function throughout the family Retroviridae. Here, we discuss the different steps in the viral life cycle that are influenced by IP6, and describe in detail how IP6 interacts with the immature and mature lattices of different retroviruses.
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Affiliation(s)
- Martin Obr
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria;
| | - Florian K. M. Schur
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria;
| | - Robert A. Dick
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
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37
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Welker L, Paillart JC, Bernacchi S. Importance of Viral Late Domains in Budding and Release of Enveloped RNA Viruses. Viruses 2021; 13:1559. [PMID: 34452424 PMCID: PMC8402826 DOI: 10.3390/v13081559] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/09/2023] Open
Abstract
Late assembly (L) domains are conserved sequences that are necessary for the late steps of viral replication, acting like cellular adaptors to engage the ESCRT membrane fission machinery that promote virion release. These short sequences, whose mutation or deletion produce the accumulation of immature virions at the plasma membrane, were firstly identified within retroviral Gag precursors, and in a further step, also in structural proteins of many other enveloped RNA viruses including arenaviruses, filoviruses, rhabdoviruses, reoviruses, and paramyxoviruses. Three classes of L domains have been identified thus far (PT/SAP, YPXnL/LXXLF, and PPxY), even if it has recently been suggested that other motifs could act as L domains. Here, we summarize the current state of knowledge of the different types of L domains and their cellular partners in the budding events of RNA viruses, with a particular focus on retroviruses.
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Affiliation(s)
| | | | - Serena Bernacchi
- Architecture et Réactivité de l’ARN, UPR 9002, IBMC, CNRS, Université de Strasbourg, F-67000 Strasbourg, France; (L.W.); (J.-C.P.)
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38
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Structural determinants of virion assembly and release in the C-terminus of the M-PMV capsid protein. J Virol 2021; 95:e0061521. [PMID: 34287037 DOI: 10.1128/jvi.00615-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The transition from an immature to a fully infectious mature retrovirus particle is associated with molecular switches that trigger dramatic conformational changes in the structure of the Gag proteins. A dominant maturation switch that stabilizes the immature capsid lattice is located downstream of the capsid (CA) protein in many retroviral Gags. The HIV-1 Gag contains a stretch of five amino acid residues termed the 'clasp motif', important for the organization of the hexameric subunits that provide stability to the overall immature HIV-1 shell. Sequence alignment of the CA C-terminal domains (CTDs) of the HIV-1 and Mason-Pfizer Monkey Virus (M-PMV) highlighted a spacer-like domain in M-PMV that may provide comparable function. The importance of the sequences spanning the CA-NC cleavage has been demonstrated by mutagenesis, but the specific requirements for the clasp motif in several steps of M-PMV particle assembly and maturation have not been determined in detail. In the present study we report an examination of the role of the clasp motif in the M-PMV life cycle. We generated a series of M-PMV Gag mutants and assayed for assembly of the recombinant protein in vitro, and for the assembly, maturation, release, genomic RNA packaging, and infectivity of the mutant virus in vivo. The mutants revealed major defects in virion assembly and release in 293T and HeLa cells, and even larger defects in infectivity. Our data identifies the clasp motif as a fundamental contributor to CA-CTD interactions necessary for efficient viral infection. Importance The C-terminal domain of the capsid protein of many retroviruses has been shown to be critical for virion assembly and maturation, but the functions of this region of M-PMV are uncertain. We show that a short 'clasp' motif in the capsid domain of the M-PMV Gag protein plays a key role in M-PMV virion assembly, genome packaging, and infectivity.
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39
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AlBurtamani N, Paul A, Fassati A. The Role of Capsid in the Early Steps of HIV-1 Infection: New Insights into the Core of the Matter. Viruses 2021; 13:v13061161. [PMID: 34204384 PMCID: PMC8234406 DOI: 10.3390/v13061161] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/10/2021] [Accepted: 06/14/2021] [Indexed: 01/27/2023] Open
Abstract
In recent years, major advances in research and experimental approaches have significantly increased our knowledge on the role of the HIV-1 capsid in the virus life cycle, from reverse transcription to integration and gene expression. This makes the capsid protein a good pharmacological target to inhibit HIV-1 replication. This review covers our current understanding of the role of the viral capsid in the HIV-1 life cycle and its interaction with different host factors that enable reverse transcription, trafficking towards the nucleus, nuclear import and integration into host chromosomes. It also describes different promising small molecules, some of them in clinical trials, as potential targets for HIV-1 therapy.
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40
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Immature HIV-1 assembles from Gag dimers leaving partial hexamers at lattice edges as potential substrates for proteolytic maturation. Proc Natl Acad Sci U S A 2021; 118:2020054118. [PMID: 33397805 PMCID: PMC7826355 DOI: 10.1073/pnas.2020054118] [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] [Indexed: 02/07/2023] Open
Abstract
HIV-1 particle assembly is driven by the viral Gag protein, which oligomerizes into a hexameric array on the inner surface of the viral envelope, forming a truncated spherical lattice containing large and small gaps. Gag is then cut by the viral protease, disassembles, and rearranges to form the mature, infectious virus. Here, we present structures and molecular dynamics simulations of the edges of the immature Gag lattice. Our analysis shows that Gag dimers are the basic assembly unit of the HIV-1 particle, lattice edges are partial hexamers, and partial hexamers are prone to structural changes allowing protease to cut Gag. These findings provide insights into assembly of the immature virus, its structure, and how it disassembles during maturation. The CA (capsid) domain of immature HIV-1 Gag and the adjacent spacer peptide 1 (SP1) play a key role in viral assembly by forming a lattice of CA hexamers, which adapts to viral envelope curvature by incorporating small lattice defects and a large gap at the site of budding. This lattice is stabilized by intrahexameric and interhexameric CA-CA interactions, which are important in regulating viral assembly and maturation. We applied subtomogram averaging and classification to determine the oligomerization state of CA at lattice edges and found that CA forms partial hexamers. These structures reveal the network of interactions formed by CA-SP1 at the lattice edge. We also performed atomistic molecular dynamics simulations of CA-CA interactions stabilizing the immature lattice and partial CA-SP1 helical bundles. Free energy calculations reveal increased propensity for helix-to-coil transitions in partial hexamers compared to complete six-helix bundles. Taken together, these results suggest that the CA dimer is the basic unit of lattice assembly, partial hexamers exist at lattice edges, these are in a helix-coil dynamic equilibrium, and partial helical bundles are more likely to unfold, representing potential sites for HIV-1 maturation initiation.
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41
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Perilla JR, Hadden-Perilla JA, Gronenborn AM, Polenova T. Integrative structural biology of HIV-1 capsid protein assemblies: combining experiment and computation. Curr Opin Virol 2021; 48:57-64. [PMID: 33901736 DOI: 10.1016/j.coviro.2021.03.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/11/2021] [Accepted: 03/20/2021] [Indexed: 12/31/2022]
Abstract
HIV-1 is the causative agent of acquired immunodeficiency syndrome (AIDS), a global pandemic that has claimed 32.7 million lives since 1981. Despite decades of research, there is no cure for the disease, with 38 million people currently infected with HIV. Attractive therapeutic targets for drug development are mature HIV-1 capsids, immature Gag polyprotein assemblies, and Gag maturation intermediates, although their complex architectures, pleomorphism, and dynamics render these assemblies challenging for structural biology. The recent development of integrative approaches, combining experimental and computational methods has enabled atomic-level characterization of structures and dynamics of capsid and Gag assemblies, and revealed their interactions with small-molecule inhibitors and host factors. These structures provide important insights that will guide the development of capsid and maturation inhibitors.
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Affiliation(s)
- Juan R Perilla
- University of Delaware, Department of Chemistry and Biochemistry, Newark, DE, United States; Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jodi A Hadden-Perilla
- University of Delaware, Department of Chemistry and Biochemistry, Newark, DE, United States
| | - Angela M Gronenborn
- Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States; Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, United States.
| | - Tatyana Polenova
- University of Delaware, Department of Chemistry and Biochemistry, Newark, DE, United States; Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
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42
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Deng Y, Hammond JA, Pauszek R, Ozog S, Chai I, Rabuck-Gibbons J, Lamichhane R, Henderson SC, Millar DP, Torbett BE, Williamson JR. Discrimination between Functional and Non-functional Cellular Gag Complexes involved in HIV-1 Assembly. J Mol Biol 2021; 433:166842. [PMID: 33539875 DOI: 10.1016/j.jmb.2021.166842] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 02/06/2023]
Abstract
HIV-1 Gag and Gag-Pol are responsible for viral assembly and maturation and represent a major paradigm for enveloped virus assembly. Numerous intracellular Gag-containing complexes (GCCs) have been identified in cellular lysates using sucrose gradient ultracentrifugation. While these complexes are universally present in Gag-expressing cells, their roles in virus assembly are not well understood. Here we demonstrate that most GCC species are predominantly comprised of monomeric or dimeric Gag molecules bound to ribosomal complexes, and as such, are not on-pathway intermediates in HIV assembly. Rather, these GCCs represent a population of Gag that is not yet functionally committed for incorporation into a viable virion precursor. We hypothesize that these complexes act as a reservoir of monomeric Gag that can incorporate into assembling viruses, and serve to mitigate non-specific intracellular Gag oligomerization. We have identified a subset of large GCC complexes, comprising more than 20 Gag molecules, that may be equivalent to membrane-associated puncta previously shown to be bona fide assembling-virus intermediates. This work provides a clear rationale for the existence of diverse GCCs, and serves as the foundation for characterizing on-pathway intermediates early in virus assembly.
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Affiliation(s)
- Yisong Deng
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - John A Hammond
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Raymond Pauszek
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Stosh Ozog
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Ilean Chai
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Jessica Rabuck-Gibbons
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Rajan Lamichhane
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Scott C Henderson
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - David P Millar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - Bruce E Torbett
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, United States
| | - James R Williamson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, United States; Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037, United States; The Skaggs Institute of Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, United States.
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43
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Mendonça L, Sun D, Ning J, Liu J, Kotecha A, Olek M, Frosio T, Fu X, Himes BA, Kleinpeter AB, Freed EO, Zhou J, Aiken C, Zhang P. CryoET structures of immature HIV Gag reveal six-helix bundle. Commun Biol 2021; 4:481. [PMID: 33863979 PMCID: PMC8052356 DOI: 10.1038/s42003-021-01999-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 03/18/2021] [Indexed: 11/09/2022] Open
Abstract
Gag is the HIV structural precursor protein which is cleaved by viral protease to produce mature infectious viruses. Gag is a polyprotein composed of MA (matrix), CA (capsid), SP1, NC (nucleocapsid), SP2 and p6 domains. SP1, together with the last eight residues of CA, have been hypothesized to form a six-helix bundle responsible for the higher-order multimerization of Gag necessary for HIV particle assembly. However, the structure of the complete six-helix bundle has been elusive. Here, we determined the structures of both Gag in vitro assemblies and Gag viral-like particles (VLPs) to 4.2 Å and 4.5 Å resolutions using cryo-electron tomography and subtomogram averaging by emClarity. A single amino acid mutation (T8I) in SP1 stabilizes the six-helix bundle, allowing to discern the entire CA-SP1 helix connecting to the NC domain. These structures provide a blueprint for future development of small molecule inhibitors that can lock SP1 in a stable helical conformation, interfere with virus maturation, and thus block HIV-1 infection.
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Affiliation(s)
- Luiza Mendonça
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Dapeng Sun
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jiying Ning
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Jiwei Liu
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Abhay Kotecha
- Thermo Fisher Scientific, Eindhoven, The Netherlands
| | - Mateusz Olek
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
- Department of Chemistry, University of York, York, UK
| | - Thomas Frosio
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK
| | - Xiaofeng Fu
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Benjamin A Himes
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Alex B Kleinpeter
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Eric O Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Jing Zhou
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Christopher Aiken
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Peijun Zhang
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK.
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Electron Bio-Imaging Centre, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, UK.
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Ghimire D, Kc Y, Timilsina U, Goel K, Nitz TJ, Wild CT, Gaur R. A single G10T polymorphism in HIV-1 subtype C Gag-SP1 regulates sensitivity to maturation inhibitors. Retrovirology 2021; 18:9. [PMID: 33836787 PMCID: PMC8033686 DOI: 10.1186/s12977-021-00553-5] [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: 12/18/2020] [Accepted: 03/23/2021] [Indexed: 08/30/2023] Open
Abstract
BACKGROUND Maturation inhibitors (MIs) potently block HIV-1 maturation by inhibiting the cleavage of the capsid protein and spacer peptide 1 (CA-SP1). Bevirimat (BVM), a highly efficacious first-in-class MI against HIV-1 subtype B isolates, elicited sub-optimal efficacy in clinical trials due to polymorphisms in the CA-SP1 region of the Gag protein (SP1:V7A). HIV-1 subtype C inherently contains this polymorphism thus conferring BVM resistance, however it displayed sensitivity to second generation BVM analogs. RESULTS In this study, we have assessed the efficacy of three novel second-generation MIs (BVM analogs: CV-8611, CV-8612, CV-8613) against HIV-1 subtype B and C isolates. The BVM analogs were potent inhibitors of both HIV-1 subtype B (NL4-3) and subtype C (K3016) viruses. Serial passaging of the subtype C, K3016 virus strain in the presence of BVM analogs led to identification of two mutant viruses-Gag SP1:A1V and CA:I201V. While the SP1:A1V mutant was resistant to the MIs, the CA:I120V mutant displayed partial resistance and a MI-dependent phenotype. Further analysis of the activity of the BVM analogs against two additional HIV-1 subtype C strains, IndieC1 and ZM247 revealed that they had reduced sensitivity as compared to K3016. Sequence analysis of the three viruses identified two polymorphisms at SP1 residues 9 and 10 (K3016: N9, G10; IndieC1/ZM247: S9, T10). The N9S and S9N mutants had no change in MI-sensitivity. On the other hand, replacing glycine at residue 10 with threonine in K3016 reduced its MI sensitivity whereas introducing glycine at SP1 10 in place of threonine in IndieC1 and ZM247 significantly enhanced their MI sensitivity. Thus, the specific glycine residue 10 of SP1 in the HIV-1 subtype C viruses determined sensitivity towards BVM analogs. CONCLUSIONS We have identified an association of a specific glycine at position 10 of Gag-SP1 with an MI susceptible phenotype of HIV-1 subtype C viruses. Our findings have highlighted that HIV-1 subtype C viruses, which were inherently resistant to BVM, may also be similarly predisposed to exhibit a significant degree of resistance to second-generation BVM analogs. Our work has strongly suggested that genetic differences between HIV-1 subtypes may produce variable MI sensitivity that needs to be considered in the development of novel, potent, broadly-active MIs.
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Affiliation(s)
- Dibya Ghimire
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110021, India
| | - Yuvraj Kc
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110021, India
| | - Uddhav Timilsina
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110021, India.,Department of Microbiology and Immunology, University at Buffalo, Buffalo, NY, 14203, USA
| | - Kriti Goel
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110021, India
| | - T J Nitz
- DFH Pharma, Gaithersburg, MD, 20886, USA
| | | | - Ritu Gaur
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110021, India.
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Toccafondi E, Lener D, Negroni M. HIV-1 Capsid Core: A Bullet to the Heart of the Target Cell. Front Microbiol 2021; 12:652486. [PMID: 33868211 PMCID: PMC8046902 DOI: 10.3389/fmicb.2021.652486] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 03/15/2021] [Indexed: 12/21/2022] Open
Abstract
The first step of the intracellular phase of retroviral infection is the release of the viral capsid core in the cytoplasm. This structure contains the viral genetic material that will be reverse transcribed and integrated into the genome of infected cells. Up to recent times, the role of the capsid core was considered essentially to protect this genetic material during the earlier phases of this process. However, increasing evidence demonstrates that the permanence inside the cell of the capsid as an intact, or almost intact, structure is longer than thought. This suggests its involvement in more aspects of the infectious cycle than previously foreseen, particularly in the steps of viral genomic material translocation into the nucleus and in the phases preceding integration. During the trip across the infected cell, many host factors are brought to interact with the capsid, some possessing antiviral properties, others, serving as viral cofactors. All these interactions rely on the properties of the unique component of the capsid core, the capsid protein CA. Likely, the drawback of ensuring these multiple functions is the extreme genetic fragility that has been shown to characterize this protein. Here, we recapitulate the busy agenda of an HIV-1 capsid in the infectious process, in particular in the light of the most recent findings.
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Affiliation(s)
| | - Daniela Lener
- CNRS, Architecture et Réactivité de l’ARN, UPR 9002, Université de Strasbourg, Strasbourg, France
| | - Matteo Negroni
- CNRS, Architecture et Réactivité de l’ARN, UPR 9002, Université de Strasbourg, Strasbourg, France
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46
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Mallery DL, Kleinpeter AB, Renner N, Faysal KMR, Novikova M, Kiss L, Wilson MSC, Ahsan B, Ke Z, Briggs JAG, Saiardi A, Böcking T, Freed EO, James LC. A stable immature lattice packages IP 6 for HIV capsid maturation. SCIENCE ADVANCES 2021; 7:7/11/eabe4716. [PMID: 33692109 PMCID: PMC7946374 DOI: 10.1126/sciadv.abe4716] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 01/21/2021] [Indexed: 05/05/2023]
Abstract
HIV virion assembly begins with the construction of an immature lattice consisting of Gag hexamers. Upon virion release, protease-mediated Gag cleavage leads to a maturation event in which the immature lattice disassembles and the mature capsid assembles. The cellular metabolite inositiol hexakisphosphate (IP6) and maturation inhibitors (MIs) both bind and stabilize immature Gag hexamers, but whereas IP6 promotes virus maturation, MIs inhibit it. Here we show that HIV is evolutionarily constrained to maintain an immature lattice stability that ensures IP6 packaging without preventing maturation. Replication-deficient mutant viruses with reduced IP6 recruitment display increased infectivity upon treatment with the MI PF46396 (PF96) or the acquisition of second-site compensatory mutations. Both PF96 and second-site mutations stabilise the immature lattice and restore IP6 incorporation, suggesting that immature lattice stability and IP6 binding are interdependent. This IP6 dependence suggests that modifying MIs to compete with IP6 for Gag hexamer binding could substantially improve MI antiviral potency.
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Affiliation(s)
- Donna L Mallery
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Alex B Kleinpeter
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Nadine Renner
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - K M Rifat Faysal
- EMBL Australia Node in Single Molecule Science and ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, UNSW Sydney, Sydney, New South Wales, Australia
| | - Mariia Novikova
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA
| | - Leo Kiss
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Miranda S C Wilson
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Bilal Ahsan
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Zunlong Ke
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - John A G Briggs
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Adolfo Saiardi
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Till Böcking
- EMBL Australia Node in Single Molecule Science and ARC Centre of Excellence in Advanced Molecular Imaging, School of Medical Sciences, UNSW Sydney, Sydney, New South Wales, Australia
| | - Eric O Freed
- Virus-Cell Interaction Section, HIV Dynamics and Replication Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702-1201, USA.
| | - Leo C James
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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47
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Abstract
Enveloped viruses exit producer cells and acquire their external lipid envelopes by budding through limiting cellular membranes. Most viruses encode multifunctional structural proteins that coordinate the processes of virion assembly, membrane envelopment, budding, and maturation. In many cases, the cellular ESCRT pathway is recruited to facilitate the membrane fission step of budding, but alternative strategies are also employed. Recently, many viruses previously considered to be non-enveloped have been shown to exit cells non-lytically within vesicles, adding further complexity to the intricacies of virus budding and egress.
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48
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Chen X, Coric P, Larue V, Turcaud S, Wang X, Nonin-Lecomte S, Bouaziz S. The HIV-1 maturation inhibitor, EP39, interferes with the dynamic helix-coil equilibrium of the CA-SP1 junction of Gag. Eur J Med Chem 2020; 204:112634. [PMID: 32717487 DOI: 10.1016/j.ejmech.2020.112634] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 11/30/2022]
Abstract
During the maturation of HIV-1 particle, the Gag polyprotein is cleaved into several proteins by the HIV-1 protease. These proteins rearrange to form infectious virus particles. In this study, the solution structure and dynamics of a monomeric mutated domain encompassing the C-terminal of capsid, the spacer peptide SP1 and the nucleocapsid from Gag was characterized by Nuclear Magnetic Resonance in the presence of maturation inhibitor EP39, a more hydro-soluble derivative of BVM. We show that the binding of EP39 decreases the dynamics of CA-SP1 junction, especially the QVT motif in SP1, and perturbs the natural coil-helix equilibrium on both sides of the SP1 domain by stabilizing the transient alpha helical structure. Our results provide new insight into the structure and dynamics of the SP1 domain and how HIV-1 maturation inhibitors interfere with this domain. They offer additional clues for the development of new second generation inhibitors targeting HIV-1 maturation.
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Affiliation(s)
- Xiaowei Chen
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France
| | - Pascale Coric
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France
| | - Valery Larue
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France
| | - Serge Turcaud
- LCBPT, CNRS, UMR 8601, Université de Paris, Paris, 45 Rue des Saints Pères, 75270, France
| | - Xiao Wang
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France
| | - Sylvie Nonin-Lecomte
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France
| | - Serge Bouaziz
- CiTCoM, CNRS, UMR 8038, Université de Paris, 4 Avenue de L'Observatoire, Paris, 75270, France.
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49
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Boyd PS, Brown JB, Brown JD, Catazaro J, Chaudry I, Ding P, Dong X, Marchant J, O’Hern CT, Singh K, Swanson C, Summers MF, Yasin S. NMR Studies of Retroviral Genome Packaging. Viruses 2020; 12:v12101115. [PMID: 33008123 PMCID: PMC7599994 DOI: 10.3390/v12101115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/18/2020] [Accepted: 09/26/2020] [Indexed: 12/03/2022] Open
Abstract
Nearly all retroviruses selectively package two copies of their unspliced RNA genomes from a cellular milieu that contains a substantial excess of non-viral and spliced viral RNAs. Over the past four decades, combinations of genetic experiments, phylogenetic analyses, nucleotide accessibility mapping, in silico RNA structure predictions, and biophysical experiments were employed to understand how retroviral genomes are selected for packaging. Genetic studies provided early clues regarding the protein and RNA elements required for packaging, and nucleotide accessibility mapping experiments provided insights into the secondary structures of functionally important elements in the genome. Three-dimensional structural determinants of packaging were primarily derived by nuclear magnetic resonance (NMR) spectroscopy. A key advantage of NMR, relative to other methods for determining biomolecular structure (such as X-ray crystallography), is that it is well suited for studies of conformationally dynamic and heterogeneous systems—a hallmark of the retrovirus packaging machinery. Here, we review advances in understanding of the structures, dynamics, and interactions of the proteins and RNA elements involved in retroviral genome selection and packaging that are facilitated by NMR.
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50
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In Vitro Quantification of the Effects of IP6 and Other Small Polyanions on Immature HIV-1 Particle Assembly and Core Stability. J Virol 2020; 94:JVI.00991-20. [PMID: 32727872 DOI: 10.1128/jvi.00991-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 07/22/2020] [Indexed: 11/20/2022] Open
Abstract
Proper assembly and disassembly of both immature and mature HIV-1 hexameric lattices are critical for successful viral replication. These processes are facilitated by several host-cell factors, one of which is myo-inositol hexaphosphate (IP6). IP6 participates in the proper assembly of Gag into immature hexameric lattices and is incorporated into HIV-1 particles. Following maturation, IP6 is also likely to participate in stabilizing capsid protein-mediated mature hexameric lattices. Although a structural-functional analysis of the importance of IP6 in the HIV-1 life cycle has been reported, the effect of IP6 has not yet been quantified. Using two in vitro methods, we quantified the effect of IP6 on the assembly of immature-like HIV-1 particles, as well as its stabilizing effect during disassembly of mature-like particles connected with uncoating. We analyzed a broad range of molar ratios of protein hexamers to IP6 molecules during assembly and disassembly. The specificity of the IP6-facilitated effect on HIV-1 particle assembly and stability was verified by K290A, K359A, and R18A mutants. In addition to IP6, we also tested other polyanions as potential assembly cofactors or stabilizers of viral particles.IMPORTANCE Various host cell factors facilitate critical steps in the HIV-1 replication cycle. One of these factors is myo-inositol hexaphosphate (IP6), which contributes to assembly of HIV-1 immature particles and helps maintain the well-balanced metastability of the core in the mature infectious virus. Using a combination of two in vitro methods to monitor assembly of immature HIV-1 particles and disassembly of the mature core-like structure, we quantified the contribution of IP6 and other small polyanion molecules to these essential steps in the viral life cycle. Our data showed that IP6 contributes substantially to increasing the assembly of HIV-1 immature particles. Additionally, our analysis confirmed the important role of two HIV-1 capsid lysine residues involved in interactions with IP6. We found that myo-inositol hexasulphate also stabilized the HIV-1 mature particles in a concentration-dependent manner, indicating that targeting this group of small molecules may have therapeutic potential.
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