Cone-shaped HIV-1 capsids are transported through intact nuclear pores

Cell, Journal Year: 2021, Volume and Issue: 184(4), P. 1032 - 1046.e18

Published: Feb. 1, 2021

Human immunodeficiency virus (HIV-1) remains a major health threat. Viral capsid uncoating and nuclear import of the viral genome are critical for productive infection. The size HIV-1 is generally believed to exceed diameter pore complex (NPC), indicating that has occur prior import. Here, we combined correlative light electron microscopy with subtomogram averaging capture structural status reverse transcription-competent complexes in infected T cells. We demonstrated NPC cellulo sufficient apparently intact, cone-shaped capsids. Subsequent import, detected disrupted empty fragments, replication occurs by breaking open, not disassembly into individual subunits. Our data directly visualize key step enhance our mechanistic understanding life cycle.

Language: Английский

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HIV-1 cores retain their integrity until minutes before uncoating in the nucleus

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(10)

Published: March 1, 2021

Significance Here, we used a fluorescent protein that is free in solution and trapped nuclear HIV-1 capsids to demonstrate the retain integrity prevent mixing of macromolecules within viral core cellular environment until just before integration. We also found capsid maintained minutes disassembly nucleus, revealing uncoating proceeds rapidly after loss. These valuable insights into early stage replication indicate intact are imported through pores, reverse transcription mostly completed capsids, preintegration complex-host interactions facilitating integration target site selection must occur short time frame between

Language: Английский

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HIV-1 uncoating by release of viral cDNA from capsid-like structures in the nucleus of infected cells

eLife, Journal Year: 2021, Volume and Issue: 10

Published: April 27, 2021

HIV-1 replication commences inside the cone-shaped viral capsid, but timing, localization, and mechanism of uncoating are under debate. We adapted a strategy to visualize individual reverse-transcribed cDNA molecules their association with cellular proteins using fluorescence correlative-light-and-electron-microscopy (CLEM). specifically detected nuclei, not in cytoplasm. Nuclear initially co-localized fluorescent integrase fusion (IN-FP) CA (capsid) protein, cDNA-punctae separated from IN-FP/CA over time. This phenotype was conserved primary target cells, nuclear complexes exhibiting strong CA-signals all cell types. CLEM revealed capsid-like structures apparently broken capsid-remnants at position IN-FP signals elongated chromatin-like punctae lacking IN-FP. Our data argue for by physical disruption rather than cooperative disassembly CA-lattice, followed separation pre-integration complex.

Language: Английский

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Liquid Biomolecular Condensates and Viral Lifecycles: Review and Perspectives

Viruses, Journal Year: 2021, Volume and Issue: 13(3), P. 366 - 366

Published: Feb. 25, 2021

Viruses are highly dependent on the host they infect. Their dependence triggers processes of virus-host co-adaptation, enabling viruses to explore resources whilst escaping immunity. Scientists have tackled viral-host interplay at differing levels complexity-in individual hosts, organs, tissues and cells-and seminal studies advanced our understanding about viral lifecycles, intra- or inter-species transmission, means control infections. Recently, it emerged as important address physical properties materials in biological systems; membrane-bound organelles only one many ways separate molecules from cellular milieu. By achieving a type compartmentalization lacking membranes known biomolecular condensates, systems developed alternative mechanisms controlling reactions. The identification that condensates display liquid led proposal liquid-liquid phase separation (LLPS) drives their formation. concept LLPS is paradigm shift structure organization. There an unprecedented momentum revisit long-standing questions virology novel antiviral strategies. In first part this review, we focus state-of-the-art condensates. second part, capture what RNA virus-phase biology discuss future perspectives emerging field virology.

Language: Английский

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The structural basis for HIV-1 Vif antagonism of human APOBEC3G

Nature, Journal Year: 2023, Volume and Issue: 615(7953), P. 728 - 733

Published: Feb. 8, 2023

Abstract The APOBEC3 (A3) proteins are host antiviral cellular that hypermutate the viral genome of diverse families. In retroviruses, this process requires A3 packaging into particles 1–4 . lentiviruses encode a protein, Vif, antagonizes family members by targeting them for degradation. Diversification allows escape from Vif whereas adaptations in enable cross-species transmission primate lentiviruses. How ‘molecular arms race’ plays out at structural level is unknown. Here, we report cryogenic electron microscopy structure human APOBEC3G (A3G) bound to HIV-1 and hijacked promote ubiquitin-mediated proteolysis. A small surface explains molecular race, including event led birth HIV-1. Unexpectedly, find RNA glue Vif–A3G interaction, enabling repress A3G ubiquitin-dependent -independent mechanisms. Our results suggest model which intercepting it its most dangerous form virus—when on pathway packaging—to prevent restriction. By engaging essential surfaces required restriction, exploits vulnerability A3G, suggesting general mechanism binding helps position key residues necessary antagonism gene.

Language: Английский

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HIV-1 capsid shape, orientation, and entropic elasticity regulate translocation into the nuclear pore complex

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(4)

Published: Jan. 19, 2024

Nuclear import and uncoating of the viral capsid are critical steps in HIV-1 life cycle that serve to transport release genomic material into nucleus. Viral core involves translocating at nuclear pore complex (NPC). Notably, central channel NPC appears often accommodate allow passage intact capsid, though mechanistic details process remain be fully understood. Here, we investigate molecular interactions operate concert between regulate translocation through channel. To this end, develop a “bottom-up” coarse-grained (CG) model human from recently released cryo-electron tomography structure then construct composite membrane-embedded CG models. We find successful cytoplasmic side is contingent on compatibility morphology dimension proper orientation approach side. The dynamics driven by maximizing contacts phenylalanine-glycine nucleoporins capsid. For docked capsids, structural analysis reveals correlated striated patterns lattice disorder likely related intrinsic elasticity. Uncondensed inside augments overall Our results suggest “elasticity” can also aid adapt stress structurally during translocation.

Language: Английский

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Passage of the HIV capsid cracks the nuclear pore

Cell, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Language: Английский

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HIV-1 Maturation: Lessons Learned from Inhibitors

Viruses, Journal Year: 2020, Volume and Issue: 12(9), P. 940 - 940

Published: Aug. 26, 2020

Since the emergence of HIV and AIDS in early 1980s, development safe effective therapies has accompanied a massive increase our understanding fundamental processes that drive biology. As basic research informed novel therapies, inhibitors have been used as probes for investigating mechanisms HIV-1 replication, transmission, pathogenesis. This positive feedback cycle led to highly combination antiretroviral therapy (cART), which helped stall progression AIDS, prolong lives, reduce transmission virus. However, combat growing rates virologic failure toxicity associated with long-term therapy, it is important diversify repertoire treatments by identifying compounds block additional steps not targeted current drugs. Most available therapeutics disrupt events replication cycle, exception protease (PR) inhibitors, act at virus maturation step. consists series biochemical changes facilitate conversion an immature, noninfectious particle mature infectious virion. These include proteolytic processing Gag polyprotein viral (PR), structural rearrangement capsid (CA) protein, assembly individual CA monomers into hexamers pentamers ultimately form capsid. Here, we review therapeutic potential (MIs), experimental class anti-HIV-1 action distinct from those PR inhibitors. We emphasize key insights biology structure study MIs provided. will focus on three groups maturation: (1) CA-spacer peptide 1 (SP1) cleavage intermediate, original term MI was applied; (2) CA-binding condensation; (3) allosteric integrase (ALLINIs) packaging RNA genome condensing during maturation. Although these classes structures action, they share ability formation condensed conical capsid, thereby blocking infectivity.

Language: Английский

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Clustering and reverse transcription of HIV‐1 genomes in nuclear niches of macrophages

The EMBO Journal, Journal Year: 2020, Volume and Issue: 40(1)

Published: Dec. 3, 2020

In order to replicate, human immunodeficiency virus (HIV-1) reverse-transcribes its RNA genome into DNA, which subsequently integrates host cell chromosomes. These two key events of the viral life cycle are commonly viewed as separate not only in time, but also cellular space, since reverse transcription (RT) is thought be completed cytoplasm before nuclear import and integration. However, spatiotemporal organization early replication macrophages, natural non-dividing target cells that constitute reservoirs HIV-1 an obstacle curing AIDS, remains unclear. Here, we demonstrate infected macrophages display large foci DNA (vDNA) RNA, multiple genomes cluster together. clusters form absence chromosomal integration, sequester paraspeckle protein CPSF6, localize speckles. Surprisingly, these consist mostly genomic, incoming both where pharmacologically suppressed untreated cells. We following temporary inhibition, can resume nucleus lead vDNA accumulation clusters. further show result transcription-competent DNA. findings change our understanding may have implications for addressing persistence.

Language: Английский

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Nuclear Capsid Uncoating and Reverse Transcription of HIV-1

Annual Review of Virology, Journal Year: 2022, Volume and Issue: 9(1), P. 261 - 284

Published: June 15, 2022

After cell entry, human immunodeficiency virus type 1 (HIV-1) replication involves reverse transcription of the RNA genome, nuclear import subviral complex without envelope breakdown, and integration viral complementary DNA into host genome. Here, we discuss recent evidence indicating that completion genome uncoating occur in nucleus rather than cytoplasm, as previously thought, suggest a testable model for uncoating. Multiple studies indicated cone-shaped capsid, which encases proteins, not only serves reaction container shield from innate immune sensors but also may constitute elusive HIV-1 factor. Rupture capsid be triggered by transcription, yet-unknown factors, or physical damage, it appears to close temporal spatial association with process.

Language: Английский

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