Dissecting translation elongation dynamics through ultra-long tracking of single ribosomes

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Апрель 8, 2024

Abstract mRNA translation by ribosomes is a highly dynamic and heterogeneous process. However, current approaches cannot readily resolve individual during translation, limiting our understanding of dynamics. Here, we develop an imaging approach based on Stopless-ORF circular RNAs (socRNAs) to monitor translating for hours. Using the socRNA technology obtained accurate measurements ribosome pausing various problematic RNA sequences or induced ribosome-targeting drugs. In addition, identified novel factor involved in elongation, revealed that translocation rates vary, indicative intracellular ribosomal heterogeneity. Finally, socRNAs allow very sensitive elongation fidelity, revealing widespread frameshifting translation. summary, single-ribosome provides detailed view kinetics powerful new tool study phase.

Язык: Английский

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Interferon-Stimulated Genes that Target Retrovirus Translation

Viruses, Год журнала: 2024, Номер 16(6), С. 933 - 933

Опубликована: Июнь 8, 2024

The innate immune system, particularly the interferon (IFN) constitutes initial line of defense against viral infections. IFN signaling induces expression interferon-stimulated genes (ISGs), and their products frequently restrict infection. Retroviruses like human immunodeficiency viruses T-lymphotropic cause severe diseases are targeted by ISG-encoded proteins. Here, we discuss ISGs that inhibit translation retroviral mRNAs thereby retrovirus propagation. Schlafen proteins degrade cellular tRNAs rRNAs needed for translation. Zinc Finger Antiviral Protein RNA-activated protein kinase initiation factors, Shiftless suppresses recoding essential enzymes. We outline common mechanisms underlie antiviral activity multifunctional potential antiretroviral therapeutic approaches based on mode action these ISGs.

Язык: Английский

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Role of human herpesvirus homologs of infected cell protein 27 (ICP27) in the biogenesis, processing, and maturation of mRNAs

mBio, Год журнала: 2025, Номер unknown

Опубликована: Март 4, 2025

ABSTRACT Herpesviruses are enveloped viruses with large double-stranded DNA genomes that highly prevalent in the human population and elicit numerous types of clinical manifestations, from mild to severe. These classified into three subfamilies: alpha -, beta gammaherpesvirinae , all capable establishing life-long persistent infections host. As strict intracellular parasites, these have evolved molecular determinants support modulate viral host gene transcription processes during infection translation messenger RNAs (mRNAs) synthesize proteins participate cellular pathways promoting their replication cycles virion formation. Notably, some functional RNA-binding domains consisting arginine-glycine-glycine (RGG) amino acid (aa) sequences that, when methylated, regulate nucleic acid-binding capacities can influence export mRNAs lacking introns nucleus cytoplasm. Additional motifs mediate interactions regulatory related RNA splicing, either or repressing mRNA processing. herpesviruses (HHVs) encode share homology infected cell protein 27 (ICP27) herpes simplex virus type 1 (HSV-1), which significantly impact biogenesis processing infection. Here, we review discuss roles ICP27 corresponding homologs encoded different herpesviruses, focusing on similarities differences structure function. A more profound knowledge role key factors required for effective herpesvirus could aid design identification novel antivirals treat diseases produced by viruses.

Язык: Английский

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The differential effect of SARS-CoV-2 NSP1 on mRNA translation and stability reveals new insights linking ribosome recruitment, codon usage, and virus evolution

Nucleic Acids Research, Год журнала: 2025, Номер 53(6)

Опубликована: Март 20, 2025

Abstract The nonstructural protein 1 (NSP1) of SARS-CoV-2 blocks the messenger RNA (mRNA) entry channel 40S ribosomal subunit, causing inhibition translation initiation and subsequent degradation host mRNAs. However, target mRNA specificity how viral mRNAs escape NSP1-mediated have not been clarified to date. Here we found that NSP1 acts as a translational switch capable blocking or enhancing depending on preinitiation complex, 43S-PIC, is recruited mRNA, whereas mostly depends codon usage bias. Thus, fast-translating with optimal for human cells preferentially recruit 43S-PIC by threading showed dramatic sensitivity NSP1. Translation escapes proper combination suboptimal slotting-prone 5′ UTR. prevalence nonoptimal codons in other coronavirus genomes favored distinctive effect plays stability.

Язык: Английский

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Dengue virus 3’ untranslated region regulates RNA genome translation

Research Square (Research Square), Год журнала: 2025, Номер unknown

Опубликована: Май 7, 2025

Viral antigenic burden drives the inflammation-driven pathophysiology of dengue in humans. Nonetheless, control virus (DENV) antigen expression for pathogenicity humans remain uncertain. Herein, we examined a clinical DENV-3 isolate (Sleman/78), along with its partially and fully attenuated derivatives through 30- (Δ30) as well 31-nucleotide deletions (Δ30/31), respectively, 3’ untranslated region (3′UTR) RNA genome; phenotypes these were demonstrated trials. We found, using infectious clone technology, protein pulldown approaches, that wild-type 3’UTR bound host translation proteins, including non-canonical eukaryotic initiation factor-3D (EIF3D) to support viral expression. Both Δ30/31 mutation EIF3D silencing hence replication Sleman/78. As DENV genome is cyclized 5’ interactions, our findings role 3′UTR regulating infection pathogenesis

Язык: Английский

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SARS-CoV-2 nsp1 mediates broad inhibition of translation in mammals

Cell Reports, Год журнала: 2025, Номер 44(5), С. 115696 - 115696

Опубликована: Май 1, 2025

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) non-structural protein 1 (nsp1) promotes innate immune evasion by inhibiting host translation in human cells. However, the role of nsp1 other species remains elusive, especially bats-natural reservoirs sarbecoviruses with a markedly different system than humans. We reveal that potently inhibits Rhinolophus lepidus bat cells, which belong to same genus as known sarbecovirus reservoir hosts. determined cryoelectron microscopy structure bound R. 40S ribosomal subunit, showing it blocks mRNA entry channel targeting highly conserved site among mammals. Accordingly, we found blocked mammalian cells from several species, underscoring its broadly inhibitory activity and numerous SARS-CoV-2 Our findings illuminate arms race between coronaviruses immunity, providing foundation for understanding determinants viral maintenance hosts spillover.

Язык: Английский

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Nonsense-mediated decay controls a negative feedback loop in innate immune sensing

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2025, Номер unknown

Опубликована: Май 14, 2025

Nonsense-mediated decay (NMD) is an mRNA pathway which degrades potential harmful transcripts that contain premature termination codons. However, NMD's importance also extends to the control of isoform abundance under physiological conditions. During viral infection, NMD inhibited through numerous mechanisms; however, has been shown have both antiviral as well proviral activities, raising further questions into role and during infection. These observations led us investigate involvement in dsRNA sensing a mechanism might explain these discrepancies. Using EIF4A2 exon 10B inclusion example AS-NMD accumulating we show inhibits NMD. This effect correlated with translational blockade driven primarily by RNaseL activation, PKR absence activation. Surprisingly, promotes induction IFN-β interferon-stimulated genes, this upstream IRF3 translocation nucleus. suggesting directly controls sensing. Therefore, inhibition upon provides negative feedback loop contributes shaping innate immune pathways.

Язык: Английский

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Distinct non-canonical translation initiation modes arise for specific host and viral mRNAs during poxvirus-induced shutoff

Nature Microbiology, Год журнала: 2025, Номер unknown

Опубликована: Май 28, 2025

Язык: Английский

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SARS-CoV-2 Nsp1 regulates translation start site fidelity to promote infection

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Июль 7, 2023

A better mechanistic understanding of virus-host interactions can help reveal vulnerabilities and identify opportunities for therapeutic interventions. Of particular interest are essential that enable production viral proteins, as those could target an early step in the virus lifecycle. Here, we use subcellular proteomics, ribosome profiling analyses reporter assays to detect changes polysome composition protein synthesis during SARS-CoV-2 (CoV2) infection. We specific translation factors molecular chaperones whose inhibition impairs infectious particle without major toxicity host. find CoV2 non-structural Nsp1 selectively enhances through functional with initiation factor EIF1A. When EIF1A is depleted, more ribosomes initiate from upstream CUG start codon, inhibiting genes reducing titers. Together, our work describes multiple dependencies on host biosynthetic networks identifies druggable targets potential antiviral development.

Язык: Английский

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Turnip mosaic virus NIb weakens the function of eukaryotic translation initiation factor 6 facilitating viral infection in Nicotiana benthamiana

Molecular Plant Pathology, Год журнала: 2024, Номер 25(2)

Опубликована: Фев. 1, 2024

Viruses rely completely on host translational machinery to produce the proteins encoded by their genes. Controlling translation initiation is important for gaining advantage in conflicts between and virus. The eukaryotic factor 4E (eIF4E) has been reported be hijacked potyviruses virus multiplication. role of regulation defence anti-defence plants viruses not well understood. We report that transcript level eIF6 was markedly increased turnip mosaic (TuMV)-infected Nicotiana benthamiana. TuMV infection impaired overexpression N. benthamiana (NbeIF6) either transiently expressed leaves or stably transgenic plants. Polysome profile assays showed NbeIF6 caused accumulation 40S 60S ribosomal subunits, reduction polysomes, also compromised UTR-mediated translation, indicating a upregulated during infection. However, polysome TuMV-infected identical overexpressing NbeIF6. Further analysis NIb protein, RNA-dependent RNA polymerase, interacted with interfered its effect suggesting might have counterdefence role. results propose possible regulatory mechanism at plant-virus interaction.

Язык: Английский

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