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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Capsid–host interactions for HIV-1 ingress

Microbiology and Molecular Biology Reviews, Journal Year: 2023, Volume and Issue: 87(4)

Published: Sept. 26, 2023

The HIV-1 capsid, composed of approximately 1,200 copies the capsid protein, encases genomic RNA alongside viral nucleocapsid, reverse transcriptase, and integrase proteins. After cell entry, interacts with a myriad host factors to traverse cytoplasm, pass through nuclear pore complex (NPC), then traffic chromosomal sites for DNA integration. Integration may very well require dissolution but where when this uncoating event occurs remains hotly debated. Based on size constraints, long-prevailing view was that preceded transport, recent research has indicated remain largely intact during import, perhaps some structural remodeling required NPC traversal. Completion transcription in nucleus further aid uncoating. One canonical type factor, typified by CPSF6, leverages Phe-Gly (FG) motif bind capsid. Recent shown these peptides reside amid prion-like domains (PrLDs), which are stretches protein sequence devoid charged residues. Intermolecular PrLD interactions along exterior shell impart avid factor binding productive infection. Herein we overview capsid-host implicated ingress discuss important questions moving forward. Highlighting clinical relevance, long-acting ultrapotent inhibitor lenacapavir, engages same pocket as FG factors, recently approved treat people living HIV.

Language: Английский

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Elasticity of the HIV-1 core facilitates nuclear entry and infection

PLoS Pathogens, Journal Year: 2024, Volume and Issue: 20(9), P. e1012537 - e1012537

Published: Sept. 11, 2024

HIV-1 infection requires passage of the viral core through nuclear pore cell, a process that depends on functions capsid. Recent studies have shown cores enter nucleus prior to capsid disassembly. Interactions with complex are necessary but not sufficient for entry, and mechanism by which traverses comparably sized is unknown. Here we show highly elastic this property linked entry infectivity. Using atomic force microscopy-based approaches, found purified wild type rapidly returned their normal conical morphology following severe compression. Results from independently performed molecular dynamic simulations mature also revealed its property. Analysis four mutants exhibit impaired mutant brittle. Adaptation two viruses in cell culture resulted additional substitutions restored elasticity rescued infectivity entry. We capsid-targeting compound PF74 antiviral drug Lenacepavir reduce block at concentrations preserve interactions between envelope. Our results indicate fundamental enables thereby facilitating infection. These provide new insights into role mechanisms inhibitors.

Language: Английский

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Lenacapavir disrupts HIV-1 core integrity while stabilizing the capsid lattice

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(14)

Published: April 1, 2025

Lenacapavir (GS-6207; LEN) is a potent HIV-1 capsid inhibitor approved for treating multidrug-resistant infection. LEN binds to hydrophobic pocket between neighboring (CA) proteins in hexamers and stabilizes the lattice, but its effect on capsids not fully understood. Here, we labeled with green fluorescent protein fused CA (GFP-CA) or fluid-phase GFP content marker (cmGFP) assess LEN’s impact capsids. cores GFP-CA, cmGFP, could be immunostained an anti-GFP antibody were less sensitive capsid-binding host restriction factor MX2, demonstrating that GFP-CA incorporated into lattice stability, whereas cmGFP indicator of core integrity. treatment isolated resulted dose-dependent loss signal while preserving signal, indicating disrupts integrity lattice. In contrast, PF-3450074 (PF74) induced Electron microscopy LEN- PF74-treated viral revealed frequent breakage at narrow end other morphological changes. Our results suggest does prevent nuclear envelope docking inhibits import without PF74 blocks by inhibiting cores, highlighting their different mechanisms inhibition.

Language: Английский

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Spatiotemporal binding of cyclophilin A and CPSF6 to capsid regulates HIV-1 nuclear entry and integration

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: April 9, 2024

Abstract Human immunodeficiency virus type 1 (HIV-1) capsid, which is the target of antiviral lenacapavir, protects viral genome and binds multiple host proteins to influence intracellular trafficking, nuclear import, integration. Previously, we showed that capsid binding cleavage polyadenylation specificity factor 6 (CPSF6) in cytoplasm competitively inhibited by cyclophilin A (CypA) regulates infection. Here determined a mutant with increased CypA affinity had significantly reduced entry mislocalized However, disruption restored entry, integration, infection CPSF6-dependent manner. Furthermore, relocalization expression from cell nucleus failed restore HIV-1 Our results clarify sequential CPSF6 required for optimal integration targeting, informing antiretroviral therapies contain lenacapavir.

Language: Английский

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Global mapping of theChlamydia trachomatisconventional secreted effector – host interactome reveals CebN interacts with nucleoporins and Rae1 to impede STAT1 nuclear translocation

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: April 26, 2024

ABSTRACT Chlamydia trachomatis ( C.t .), the leading cause of bacterial sexually transmitted infections, employs a type III secretion system (T3SS) to translocate two classes effectors, inclusion membrane proteins and conventional T3SS (cT3SS) into host cell counter defense mechanisms. Here we employed three assays directly evaluate during infection, validating for 23 cT3SS effectors. As bioinformatic analyses have been largely unrevealing, conducted affinity purification-mass spectrometry identify targets gain insights functions these identifying high confidence interacting partners 21 We demonstrate that CebN localizes nuclear envelope in infected bystander cells where it interacts with multiple nucleoporins Rae1, blocking STAT1 import following IFN-γ stimulation. By building effector-host interactome, identified novel pathways are targeted infection begun address how C.t. effectors combat autonomous immunity.

Language: Английский

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HIV capsids: orchestrators of innate immune evasion, pathogenesis and pandemicity

Journal of General Virology, Journal Year: 2025, Volume and Issue: 106(1)

Published: Jan. 13, 2025

Human immunodeficiency virus (HIV) is an exemplar virus, still the most studied and best understood a model for mechanisms of viral replication, immune evasion pathogenesis. In this review, we consider earliest stages HIV infection from transport virion contents through cytoplasm to integration genome into host chromatin. We present holistic virus-host interaction during pivotal stage infection. Central process capsid. The last 10 years have seen transformation in way understand capsid structure function. review key discoveries our latest thoughts on as dynamic regulator innate chromatin targeting. also accessory proteins Vpr Vpx because they are incorporated particles where collaborate with capsids manipulate defensive cellular responses argue that effective regulation uncoating immunity define pandemic potential pathogenesis, how comparison different lineages can reveal what makes lentiviruses special.

Language: Английский

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The nuclear localization signal of CPSF6 governs post-nuclear import steps of HIV-1 infection

PLoS Pathogens, Journal Year: 2025, Volume and Issue: 21(1), P. e1012354 - e1012354

Published: Jan. 17, 2025

The early stages of HIV-1 infection include the trafficking viral core into nucleus infected cells. However, much remains to be understood about how accomplishes nuclear import and consequences pathways utilized on events. host factor cleavage polyadenylation specificity 6 (CPSF6) assists localization post-entry integration targeting. Here, we used a CPSF6 truncation mutant lacking functional signal (NLS), CPSF6-358, appended heterologous NLSs rescue localization. We show that some, but not all, drive CPSF6-358 nucleus. Interestingly, found some localized CPSF6-NLS chimeras supported inefficient infection. still enters in these cell lines fails traffic speckle-associated domains (SPADs). Additionally, efficiently integrate lines. Collectively, our results demonstrate NLS facilitates steps subsequent additionally identify ability canonical sequences influence cargo following import.

Language: Английский

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Structural insights into HIV-2 CA lattice formation and FG-pocket binding revealed by single-particle cryo-EM

Cell Reports, Journal Year: 2025, Volume and Issue: 44(2), P. 115245 - 115245

Published: Jan. 25, 2025

Language: Английский

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CPSF6 Promotes HIV-1 Preintegration Complex Function

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 29, 2025

ABSTRACT Cleavage and polyadenylation specificity factor 6 (CPSF6) is part of the cellular cleavage I mammalian (CFIm) complex that regulates mRNA processing polyadenylation. CPSF6 also functions as a HIV-1 capsid (CA) binding host promotes viral DNA integration targeting into gene dense regions genome. However, effects on activity preintegration (PIC) - machinery carries out to establish infection unknown. To study CPSF6’s role in PIC function, we extracted PICs from cells depleted or expressing mutant cannot bind CA. These exhibited significantly lower when compared control PICs. Addition recombinant restored cells, suggesting direct function. solidify effect inoculated CPSF6-depleted CPSF6-mutant with particles measured A significant reduction these was detected this defect not consequence reduced reverse transcription nuclear entry. Additionally, viruses deficient CA-CPSF6 showed no cells. Finally, sequencing analysis revealed redirected Collectively, results suggest CPSF6-CA interaction function both vitro infected IMPORTANCE dependent virus factors. molecular details virus-host interactions are fully understood. For instance, provides interfaces for several one such capsid-binding factor, whose regulate Initial work identified truncated cytosolic form restricted HIV by blocking it now established full-length primarily Here report complexes (PICs). We observed disruption target directed away gene-dense regions. findings demonstrate critical targeting.

Language: Английский

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