Proteolytic activation of SARS‐CoV‐2 spike protein

Microbiology and Immunology, Journal Year: 2021, Volume and Issue: 66(1), P. 15 - 23

Published: Sept. 25, 2021

Spike (S) protein cleavage is a crucial step in coronavirus infection. In this review, process discussed, with particular focus on the novel coronavirus, severe acute respiratory syndrome 2 (SARS-CoV-2). Compared influenza virus and paramyxovirus membrane fusion proteins, activation mechanism of S much more complex. The has two sites (S1/S2 S2'), motif for furin protease at S1/S2 site that results from unique four-amino acid insertion one distinguishing features SARS-CoV-2. viral particle incorporates protein, which already undergone by furin, then undergoes further S2' site, mediated type II transmembrane serine (TMPRSS2), after binding to receptor angiotensin-converting enzyme (ACE2) facilitate plasma membrane. addition, SARS-CoV-2 can enter cell endocytosis be proteolytically activated cathepsin L, although not major mode variants enhanced infectivity have been emerging throughout ongoing pandemic, there close relationship between changes cleavability. All four concern carry D614G mutation, indirectly enhances cleavability furin. P681R mutation delta variant directly increases cleavability, enhancing virulence. Changes significantly impact infectivity, tissue tropism, Understanding these mechanisms critical counteracting pandemic.

Language: Английский

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Chemical-guided SHAPE sequencing (cgSHAPE-seq) informs the binding site of RNA-degrading chimeras targeting SARS-CoV-2 5’ untranslated region

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 8, 2025

One of the hallmarks RNA viruses is highly structured untranslated regions (UTRs) which are often essential for viral replication, transcription, or translation. In this report, we discovered a series coumarin derivatives that bind to four-way helix called SL5 in 5' UTR SARS-CoV-2 genome. To locate binding site, developed sequencing-based method namely cgSHAPE-seq, an acylating probe was directed crosslink with 2'-OH group ribose at site create read-through mutations during reverse transcription. cgSHAPE-seq unambiguously determined bulged G as primary validated through mutagenesis and vitro experiments. The were further used warhead designing RNA-degrading chimeras reduce expression levels. optimized chimera C64 inhibited live virus replication lung epithelial carcinoma cells. Highly serve potential drug targets. Here authors identified class small molecules Using they pinpointed inhibit replication.

Language: Английский

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QTQTN motif upstream of the furin-cleavage site plays a key role in SARS-CoV-2 infection and pathogenesis

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(32)

Published: July 26, 2022

The furin cleavage site (FCS), an unusual feature in the SARS-CoV-2 spike protein, has been spotlighted as a factor key to facilitating infection and pathogenesis by increasing processing. Similarly, QTQTN motif directly upstream of FCS is also for group 2B coronaviruses (CoVs). deletion consistently observed vitro cultured virus stocks some clinical isolates. To determine whether critical replication pathogenesis, we generated mutant deleting (ΔQTQTN). Here, report that attenuates viral respiratory cells disease vivo. results shortened, more rigid peptide loop contains less accessible host proteases, such TMPRSS2. Thus, reduced efficiency processing infection. Importantly, residues are glycosylated, disruption its glycosylation TMPRSS2-dependent manner. Together, our reveal three aspects S1/S2 site—the FCS, length, glycosylation—are required efficient pathogenesis.

Language: Английский

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Identification and differential usage of a host metalloproteinase entry pathway by SARS-CoV-2 Delta and Omicron

iScience, Journal Year: 2022, Volume and Issue: 25(11), P. 105316 - 105316

Published: Oct. 10, 2022

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) spike glycoprotein (S) binds to angiotensin-converting enzyme 2 (ACE2) mediate membrane fusion via two distinct pathways: 1) a surface, serine protease-dependent or 2) an endosomal, cysteine pathway. In this study, we found that SARS-CoV-2 S has wider protease usage and can also be activated by TMPRSS13 matrix metalloproteinases (MMPs). We MMP-2 MMP-9 played roles in cell-cell TMPRSS2- cathepsin-independent viral entry cells expressing high MMP levels. MMP-dependent required cleavage at the S1/S2 junction producer cells, differential processing of variants concern dictated its usage; efficiently processed Delta preferred metalloproteinase-dependent when available, less Omicron was unable us for entry. As MMP-2/9 are released during inflammation, they may play S-mediated cytopathic effects, tropism, disease outcome.

Language: Английский

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Preclinical immunogenicity and efficacy of a candidate COVID-19 vaccine based on a vesicular stomatitis virus-SARS-CoV-2 chimera

EBioMedicine, Journal Year: 2022, Volume and Issue: 82, P. 104203 - 104203

Published: July 30, 2022

To investigate a vaccine technology with potential to protect against coronavirus disease 2019 (COVID-19) and reduce transmission of severe acute respiratory syndrome 2 (SARS-CoV-2) single dose, we developed SARS-CoV-2 candidate using the live vesicular stomatitis virus (VSV) chimeric approach previously used develop licensed Ebola vaccine.We generated replication-competent VSV-SARS-CoV-2 by replacing VSV glycoprotein (G) gene coding sequence for Spike (S). Immunogenicity lead (VSV∆G-SARS-CoV-2) was evaluated in cotton rats golden Syrian hamsters, protection from infection also assessed hamsters.VSV∆G-SARS-CoV-2 delivered intramuscular (IM) injection immunogenic hamsters protected weight loss following challenge. When mucosal vaccination evaluated, did not respond vaccine, whereas administration VSV∆G-SARS-CoV-2 found be more than IM induced immunity that significantly reduced challenge loads both lung nasal tissues.VSV∆G-SARS-CoV-2 or methods effectively infection. Hamsters vaccinated application controlled replication tissue.The study funded Merck Sharp & Dohme, Corp., subsidiary Co., Inc., Rahway, NJ, USA, The International AIDS Vaccine Initiative, Inc. (IAVI), New York, USA. Parts this research supported Biomedical Advanced Research Development Authority (BARDA) Defense Threat Reduction Agency (DTRA) US Department Defense.

Language: Английский

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Pulmonary surfactant and COVID-19: A new synthesis

QRB Discovery, Journal Year: 2022, Volume and Issue: 3

Published: Jan. 1, 2022

COVID-19 pathogenesis poses paradoxes difficult to explain with traditional physiology. For instance, since type II pneumocytes are considered the primary cellular target of SARS-CoV-2; as these produce pulmonary surfactant (PS), possibility that insufficient PS plays a role in has been raised. However, opposite predicted high alveolar surface tension is found many early patients: paradoxically normal lung volumes and compliance occur, profound hypoxemia. That 'COVID anomaly' was quickly rationalised by invoking vascular mechanisms-mainly because surprisingly preserved hypoxemic cases. quick rejection damage only occurred actual mechanism gas exchange long presumed be non-problematic, due diffusion through surface. On contrary, we provide physical chemical evidence occurs an process expansion contraction three-dimensional structures its associated proteins. This view explains anomalous observations from level cryo-TEM whole individuals. It encompasses results premature infants deepest diving seals. Once understood, COVID anomaly dissolves straightforwardly explained covert viral 3D structure PS, direct treatment implications. As natural experiment, SARS-CoV-2 virus itself helped us simplify clarify not nature dyspnea relationship compliance, but also fine detail including such features water channels which had heretofore entirely unexpected.For time, physical, colloid chemistry have intersected physiology cell biology much might hoped. The reasons starting become clear. discipline suffered serious unrecognised omissions rendered it ineffective. These foundational defects included omission specific ion molecular forces hydration effects. lacked predictive theory self-assembly lipids Worse, omitted any for dissolved gases, O2, N2, CO2, their existence stable nanobubbles above physiological salt concentration. Recent developments gone some way explaining foam-like function. delivers O2/N2 nanobubbles, efflux H2O at Knowledge allows explanation corona entry, differences infectivity different variants. CO2 resulting metabolism passing frit provided glycocalyx venous tissue, forms previously unexplained foam endothelial layer. turn out lethal viruses, providing plausible origin 'Long COVID'. Circulating 0.17 M drive various enzyme-like activities reactions. Awareness microstructure Pulmonary Surfactant (O2/N2) integral respiratory circulatory provides new insights other pathogen activity.

Language: Английский

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Chemical-guided SHAPE sequencing (cgSHAPE-seq) informs the binding site of RNA-degrading chimeras targeting SARS-CoV-2 5’ untranslated region

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: April 4, 2023

One of the hallmarks RNA viruses is highly structured untranslated regions (UTRs) in their genomes. These conserved structures are often essential for viral replication, transcription, or translation. In this report, we discovered and optimized a new type coumarin derivatives, such as C30 C34 , which bind to four-way helix called SL5 5’ UTR SARS-CoV-2 genome. To locate binding site, developed novel sequencing-based method namely cgSHAPE-seq, acylating chemical probe was directed crosslink with 2’-OH groups ribose at ligand site. This crosslinked could then create read-through mutations during reverse transcription (i.e., primer extension) single-nucleotide resolution uncover acylation locations. cgSHAPE-seq unambiguously determined that bulged G primary site UTR, validated through mutagenesis vitro experiments. further used warhead RNA-degrading chimeras reduce expression levels. We demonstrated replacing moiety cgSHAPE ribonuclease L recruiter (RLR) moieties yielded degraders active RNase degradation assay expressing cells. explored another RLR conjugation on E ring C30/C34 improved activities The chimera C64 inhibited live virus replication lung epithelial carcinoma

Language: Английский

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Repurposing Niclosamide as a Novel Anti-SARS-CoV-2 Drug by Restricting Entry Protein CD147

Biomedicines, Journal Year: 2023, Volume and Issue: 11(7), P. 2019 - 2019

Published: July 18, 2023

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the global disease 2019 (COVID-19) pandemic, and search for effective treatments been limited. Furthermore, rapid mutations SARS-CoV-2 have posed challenges existing vaccines neutralizing antibodies, as they struggle keep up with increased viral transmissibility immune evasion. However, there is hope in targeting CD147-spike protein, which serves an alternative point entry into host cells. This protein emerged a promising therapeutic target development drugs against COVID-19. Here, we demonstrate that RNA-binding Human-antigen R (HuR) plays crucial role post-transcriptional regulation CD147 by directly binding its 3'-untranslated region (UTR). We observed decrease levels across multiple cell lines upon HuR depletion. identified niclosamide can reduce lowering cytoplasmic translocation reducing glycosylation. Moreover, our investigation revealed infection induces upregulation ACE2-expressing A549 cells, be effectively neutralized dose-dependent manner. Overall, study unveils novel regulatory mechanism regulating through suggests option

Language: Английский

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Cell type dependent stability and virulence of a recombinant SARS-CoV-2, and engineering of a propagation deficient RNA replicon to analyze virus RNA synthesis

Frontiers in Cellular and Infection Microbiology, Journal Year: 2023, Volume and Issue: 13

Published: Oct. 24, 2023

Engineering of reverse genetics systems for newly emerged viruses allows viral genome manipulation, being an essential tool the study virus life cycle, virus-host interactions and pathogenesis, as well development effective antiviral strategies. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emergent human that has caused disease (COVID-19) pandemic. The engineering a full-length infectious cDNA clone fluorescent replicon SARS-CoV-2 Wuhan-Hu-1, using bacterial artificial chromosome, reported. Viral growth genetic stability in eleven cell lines were analyzed, showing both VeroE6 cells overexpressing transmembrane serin protease (TMPRSS2) lung derived resulted optimization system to preserve stability. recombinant point mutant expressing D614G spike protein variant virulent mouse model. RNA was propagation-defective, allowing its use BSL-2 conditions analyze synthesis. developed constitute useful studying molecular biology virus, genetically defined vaccines establish compounds screening.

Language: Английский

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Transcriptomic approaches in COVID-19: From infection to vaccines

Elsevier eBooks, Journal Year: 2023, Volume and Issue: unknown, P. 125 - 144

Published: Jan. 1, 2023

Language: Английский

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