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J Virol ; 96(5): e0208621, 2022 03 09.
Article in English | MEDLINE | ID: covidwho-1736026


Coronavirus infections induce the expression of multiple proinflammatory cytokines and chemokines. We have previously shown that in cells infected with gammacoronavirus infectious bronchitis virus (IBV), interleukin 6 (IL-6), and IL-8 were drastically upregulated, and the MAP kinase p38 and the integrated stress response pathways were implicated in this process. In this study, we report that coronavirus infection activates a negative regulatory loop that restricts the upregulation of a number of proinflammatory genes. As revealed by the initial transcriptomic and subsequent validation analyses, the anti-inflammatory adenine-uridine (AU)-rich element (ARE)-binding protein, zinc finger protein 36 (ZFP36), and its related family members were upregulated in cells infected with IBV and three other coronaviruses, alphacoronaviruses porcine epidemic diarrhea virus (PEDV), human coronavirus 229E (HCoV-229E), and betacoronavirus HCoV-OC43, respectively. Characterization of the functional roles of ZFP36 during IBV infection demonstrated that ZFP36 promoted the degradation of transcripts coding for IL-6, IL-8, dual-specificity phosphatase 1 (DUSP1), prostaglandin-endoperoxide synthase 2 (PTGS2) and TNF-α-induced protein 3 (TNFAIP3), through binding to AREs in these transcripts. Consistently, knockdown and inhibition of JNK and p38 kinase activities reduced the expression of ZFP36, as well as the expression of IL-6 and IL-8. On the contrary, overexpression of mitogen-activated protein kinase kinase 3 (MKK3) and MAPKAP kinase-2 (MK2), the upstream and downstream kinases of p38, respectively, increased the expression of ZFP36 and decreased the expression of IL-8. Taken together, this study reveals an important regulatory role of the MKK3-p38-MK2-ZFP36 axis in coronavirus infection-induced proinflammatory response. IMPORTANCE Excessive and uncontrolled induction and release of proinflammatory cytokines and chemokines, the so-called cytokine release syndrome (CRS), would cause life-threatening complications and multiple organ failure in severe coronavirus infections, including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and COVID-19. This study reveals that coronavirus infection also induces the expression of ZFP36, an anti-inflammatory ARE-binding protein, promoting the degradation of ARE-containing transcripts coding for IL-6 and IL-8 as well as a number of other proteins related to inflammatory response. Furthermore, the p38 MAP kinase, its upstream kinase MKK3 and downstream kinase MK2 were shown to play a regulatory role in upregulation of ZFP36 during coronavirus infection cycles. This MKK3-p38-MK2-ZFP36 axis would constitute a potential therapeutic target for severe coronavirus infections.

Coronavirus Infections/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Tristetraprolin/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , Adenine/metabolism , Animals , Cell Line , Chlorocebus aethiops , Coronavirus Infections/genetics , Gene Expression Regulation , Humans , Infectious bronchitis virus/metabolism , Infectious bronchitis virus/pathogenicity , Interleukin-6/genetics , Interleukin-8/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Phosphorylation , Protein Serine-Threonine Kinases/metabolism , Transcriptional Activation , Up-Regulation , Uridine/metabolism , Vero Cells
J Am Chem Soc ; 143(48): 20095-20108, 2021 12 08.
Article in English | MEDLINE | ID: covidwho-1531986


Chemical modifications of native proteins can affect their stability, activity, interactions, localization, and more. However, there are few nongenetic methods for the installation of chemical modifications at a specific protein site in cells. Here we report a covalent ligand directed release (CoLDR) site-specific labeling strategy, which enables the installation of a variety of functional tags on a target protein while releasing the directing ligand. Using this approach, we were able to label various proteins such as BTK, K-RasG12C, and SARS-CoV-2 PLpro with different tags. For BTK we have shown selective labeling in cells of both alkyne and fluorophores tags. Protein labeling by traditional affinity methods often inhibits protein activity since the directing ligand permanently occupies the target binding pocket. We have shown that using CoLDR chemistry, modification of BTK by these probes in cells preserves its activity. We demonstrated several applications for this approach including determining the half-life of BTK in its native environment with minimal perturbation, as well as quantification of BTK degradation by a noncovalent proteolysis targeting chimera (PROTAC) by in-gel fluorescence. Using an environment-sensitive "turn-on" fluorescent probe, we were able to monitor ligand binding to the active site of BTK. Finally, we have demonstrated efficient CoLDR-based BTK PROTACs (DC50 < 100 nM), which installed a CRBN binder onto BTK. This approach joins very few available labeling strategies that maintain the target protein activity and thus makes an important addition to the toolbox of chemical biology.

Agammaglobulinaemia Tyrosine Kinase/chemistry , Fluorescent Dyes/chemistry , Ligands , Proto-Oncogene Proteins p21(ras)/antagonists & inhibitors , Adenine/analogs & derivatives , Adenine/chemistry , Adenine/metabolism , Agammaglobulinaemia Tyrosine Kinase/metabolism , Catalytic Domain , Coronavirus Papain-Like Proteases/chemistry , Coronavirus Papain-Like Proteases/metabolism , Half-Life , Humans , Piperidines/chemistry , Piperidines/metabolism , Proteolysis , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Pyrimidines/chemistry , Pyrimidines/metabolism , SARS-CoV-2/enzymology
Sci Rep ; 11(1): 19998, 2021 10 07.
Article in English | MEDLINE | ID: covidwho-1462031


Understanding the effects of metabolism on the rational design of novel and more effective drugs is still a considerable challenge. To the best of our knowledge, there are no entirely computational strategies that make it possible to predict these effects. From this perspective, the development of such methodologies could contribute to significantly reduce the side effects of medicines, leading to the emergence of more effective and safer drugs. Thereby, in this study, our strategy is based on simulating the electron ionization mass spectrometry (EI-MS) fragmentation of the drug molecules and combined with molecular docking and ADMET models in two different situations. In the first model, the drug is docked without considering the possible metabolic effects. In the second model, each of the intermediates from the EI-MS results is docked, and metabolism occurs before the drug accesses the biological target. As a proof of concept, in this work, we investigate the main antiviral drugs used in clinical research to treat COVID-19. As a result, our strategy made it possible to assess the biological activity and toxicity of all potential by-products. We believed that our findings provide new chemical insights that can benefit the rational development of novel drugs in the future.

Antiviral Agents/metabolism , COVID-19 Drug Treatment , Drug Discovery , SARS-CoV-2/drug effects , Adenine/adverse effects , Adenine/analogs & derivatives , Adenine/metabolism , Adenine/pharmacology , Adenosine/adverse effects , Adenosine/analogs & derivatives , Adenosine/metabolism , Adenosine/pharmacology , Adenosine Monophosphate/adverse effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/metabolism , Adenosine Monophosphate/pharmacology , Alanine/adverse effects , Alanine/analogs & derivatives , Alanine/metabolism , Alanine/pharmacology , Amides/adverse effects , Amides/metabolism , Amides/pharmacology , Antiviral Agents/adverse effects , Antiviral Agents/pharmacology , COVID-19/metabolism , Chloroquine/adverse effects , Chloroquine/analogs & derivatives , Chloroquine/metabolism , Chloroquine/pharmacology , Drug Design , Humans , Metabolic Networks and Pathways , Molecular Docking Simulation , Nitro Compounds/adverse effects , Nitro Compounds/metabolism , Nitro Compounds/pharmacology , Pyrazines/adverse effects , Pyrazines/metabolism , Pyrazines/pharmacology , Pyrrolidines/adverse effects , Pyrrolidines/metabolism , Pyrrolidines/pharmacology , Ribavirin/adverse effects , Ribavirin/metabolism , Ribavirin/pharmacology , SARS-CoV-2/metabolism , Thiazoles/adverse effects , Thiazoles/metabolism , Thiazoles/pharmacology
Int J Mol Sci ; 22(13)2021 Jun 30.
Article in English | MEDLINE | ID: covidwho-1288906


Coronavirus disease (COVID)-19 is the leading global health threat to date caused by a severe acute respiratory syndrome coronavirus (SARS-CoV-2). Recent clinical trials reported that the use of Bruton's tyrosine kinase (BTK) inhibitors to treat COVID-19 patients could reduce dyspnea and hypoxia, thromboinflammation, hypercoagulability and improve oxygenation. However, the mechanism of action remains unclear. Thus, this study employs structure-based virtual screening (SBVS) to repurpose BTK inhibitors acalabrutinib, dasatinib, evobrutinib, fostamatinib, ibrutinib, inositol 1,3,4,5-tetrakisphosphate, spebrutinib, XL418 and zanubrutinib against SARS-CoV-2. Molecular docking is conducted with BTK inhibitors against structural and nonstructural proteins of SARS-CoV-2 and host targets (ACE2, TMPRSS2 and BTK). Molecular mechanics-generalized Born surface area (MM/GBSA) calculations and molecular dynamics (MD) simulations are then carried out on the selected complexes with high binding energy. Ibrutinib and zanubrutinib are found to be the most potent of the drugs screened based on the results of computational studies. Results further show that ibrutinib and zanubrutinib could exploit different mechanisms at the viral entry and replication stage and could be repurposed as potential inhibitors of SARS-CoV-2 pathogenesis.

Adenine/analogs & derivatives , Drug Repositioning , Molecular Dynamics Simulation , Piperidines/chemistry , Protein Kinase Inhibitors/chemistry , Pyrazoles/chemistry , Pyrimidines/chemistry , Adenine/chemistry , Adenine/metabolism , Adenine/therapeutic use , Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Agammaglobulinaemia Tyrosine Kinase/metabolism , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/metabolism , Binding Sites , COVID-19/pathology , COVID-19/virology , Humans , Molecular Docking Simulation , Piperidines/metabolism , Piperidines/therapeutic use , Protein Kinase Inhibitors/metabolism , Protein Kinase Inhibitors/therapeutic use , Pyrazoles/metabolism , Pyrazoles/therapeutic use , Pyrimidines/metabolism , Pyrimidines/therapeutic use , SARS-CoV-2/isolation & purification , SARS-CoV-2/metabolism , Serine Endopeptidases/chemistry , Serine Endopeptidases/metabolism , Thermodynamics , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Nonstructural Proteins/metabolism , COVID-19 Drug Treatment
Elife ; 92020 11 23.
Article in English | MEDLINE | ID: covidwho-940328


Bruton's tyrosine kinase (BTK) is targeted in the treatment of B-cell disorders including leukemias and lymphomas. Currently approved BTK inhibitors, including Ibrutinib, a first-in-class covalent inhibitor of BTK, bind directly to the kinase active site. While effective at blocking the catalytic activity of BTK, consequences of drug binding on the global conformation of full-length BTK are unknown. Here, we uncover a range of conformational effects in full-length BTK induced by a panel of active site inhibitors, including large-scale shifts in the conformational equilibria of the regulatory domains. Additionally, we find that a remote Ibrutinib resistance mutation, T316A in the BTK SH2 domain, drives spurious BTK activity by destabilizing the compact autoinhibitory conformation of full-length BTK, shifting the conformational ensemble away from the autoinhibited form. Future development of BTK inhibitors will need to consider long-range allosteric consequences of inhibitor binding, including the emerging application of these BTK inhibitors in treating COVID-19.

Treatments for blood cancers, such as leukemia and lymphoma, rely heavily on chemotherapy, using drugs that target a vulnerable aspect of the cancer cells. B-cells, a type of white blood cell that produces antibodies, require a protein called Bruton's tyrosine kinase, or BTK for short, to survive. The drug ibrutinib (Imbruvica) is used to treat B-cell cancers by blocking BTK. The BTK protein consists of several regions. One of them, known as the kinase domain, is responsible for its activity as an enzyme (which allows it to modify other proteins by adding a 'tag' known as a phosphate group). The other regions of BTK, known as regulatory modules, control this activity. In BTK's inactive form, the regulatory modules attach to the kinase domain, blocking the regulatory modules from interacting with other proteins. When BTK is activated, it changes its conformation so the regulatory regions detach and become available for interactions with other proteins, at the same time exposing the active kinase domain. Ibrutinib and other BTK drugs in development bind to the kinase domain to block its activity. However, it is not known how this binding affects the regulatory modules. Previous efforts to study how drugs bind to BTK have used a version of the protein that only had the kinase domain, instead of the full-length protein. Now, Joseph et al. have studied full-length BTK and how it binds to five different drugs. The results reveal that ibrutinib and another drug called dasatinib both indirectly disrupt the normal position of the regulatory domains pushing BTK toward a conformation that resembles the activated state. By contrast, the three other compounds studied do not affect the inactive structure. Joseph et al. also examined a mutation in BTK that confers resistance against ibrutinib. This mutation increases the activity of BTK by disrupting the inactive structure, leading to B cells surviving better. Understanding how drug resistance mechanisms can work will lead to better drug treatment strategies for cancer. BTK is also a target in other diseases such as allergies or asthma and even COVID-19. If interactions between partner proteins and the regulatory domain are important in these diseases, then they may be better treated with drugs that maintain the regulatory modules in their inactive state. This research will help to design drugs that are better able to control BTK activity.

Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Catalytic Domain , Protein Conformation/drug effects , Protein Kinase Inhibitors/pharmacology , Adenine/analogs & derivatives , Adenine/chemistry , Adenine/metabolism , Adenine/pharmacology , Agammaglobulinaemia Tyrosine Kinase/chemistry , Agammaglobulinaemia Tyrosine Kinase/genetics , COVID-19/metabolism , COVID-19/prevention & control , COVID-19/virology , Dasatinib/chemistry , Dasatinib/metabolism , Dasatinib/pharmacology , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/prevention & control , Models, Molecular , Molecular Structure , Mutation , Piperidines/chemistry , Piperidines/metabolism , Piperidines/pharmacology , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , SARS-CoV-2/physiology , src Homology Domains/genetics
J Phys Chem Lett ; 11(11): 4430-4435, 2020 Jun 04.
Article in English | MEDLINE | ID: covidwho-233085


The pandemic outbreak of a new coronavirus (CoV), SARS-CoV-2, has captured the world's attention, demonstrating that CoVs represent a continuous global threat. As this is a highly contagious virus, it is imperative to understand RNA-dependent-RNA-polymerase (RdRp), the key component in virus replication. Although the SARS-CoV-2 genome shares 80% sequence identity with severe acute respiratory syndrome SARS-CoV, their RdRps and nucleotidyl-transferases (NiRAN) share 98.1% and 93.2% identity, respectively. Sequence alignment of six coronaviruses demonstrated higher identity among their RdRps (60.9%-98.1%) and lower identity among their Spike proteins (27%-77%). Thus, a 3D structural model of RdRp, NiRAN, non-structural protein 7 (nsp7), and nsp8 of SARS-CoV-2 was generated by modeling starting from the SARS counterpart structures. Furthermore, we demonstrate the binding poses of three viral RdRp inhibitors (Galidesivir, Favipiravir, and Penciclovir), which were recently reported to have clinical significance for SARS-CoV-2. The network of interactions established by these drug molecules affirms their efficacy to inhibit viral RNA replication and provides an insight into their structure-based rational optimization for SARS-CoV-2 inhibition.

Betacoronavirus/enzymology , Nucleotidyltransferases/chemistry , RNA-Dependent RNA Polymerase/chemistry , Adenine/analogs & derivatives , Adenine/chemistry , Adenine/metabolism , Adenosine/analogs & derivatives , Amides/chemistry , Amides/metabolism , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Betacoronavirus/isolation & purification , Binding Sites , COVID-19 , Coronavirus Infections/epidemiology , Coronavirus Infections/pathology , Coronavirus Infections/virology , Humans , Molecular Docking Simulation , Nucleotidyltransferases/metabolism , Pandemics , Pneumonia, Viral/epidemiology , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Protein Structure, Tertiary , Pyrazines/chemistry , Pyrazines/metabolism , Pyrrolidines/chemistry , Pyrrolidines/metabolism , RNA-Dependent RNA Polymerase/metabolism , SARS-CoV-2