Mutations in the human tau gene leading to aberrant splicing have been identified in FTDP-17, an autosomal dominant hereditary neurodegenerative disorder. Molecular mechanisms by which such mutations cause tau aberrant splicing were not understood. We characterized two mutations in exon 10 of the tau gene, N279K and Del280K. Our results revealed an exonic splicing enhancer element located in exon 10. The activity of this AG-rich splicing enhancer was altered by N279K and Del280K mutations. This exonic enhancer element interacts with human Tra2β protein. The interaction between Tra2β and the exonic splicing enhancer correlates with the activity of this enhancer element in stimulating splicing. Biochemical studies including in vitro splicing and RNA interference experiments in transfected cells support a role for Tra2β protein in regulating alternative splicing of human tau gene. Our results implicate the human tau gene as a target gene for the alternative splicing regulator Tra2β, suggesting that Tra2β may play a role in aberrant tau exon 10 alternative splicing and in the pathogenesis of tauopathies.

Thiolutin, an inhibitor of the BRISC deubiquitinating enzyme complex, specifically and potently inhibits NLRP3 inflammasome activation.

The precise cellular mechanisms underlying heightened proinflammatory cytokine production during coronavirus infection remain incompletely understood. Here we identify the envelope (E) protein in severe coronaviruses (SARS-CoV-2, SARS, or MERS) as a potent inducer of interleukin-1 release, intensifying lung inflammation through the activation of TMED10-mediated unconventional protein secretion (UcPS). In contrast, the E protein of mild coronaviruses (229E, HKU1, or OC43) demonstrates a less pronounced effect. The E protein of severe coronaviruses contains an SS/DS motif, which is not present in milder strains and facilitates interaction with TMED10. This interaction enhances TMED10-oligomerization, facilitating UcPS cargo translocation into the ER-Golgi intermediate compartment (ERGIC)—a pivotal step in interleukin-1 UcPS. Progesterone analogues were identified as compounds inhibiting E-enhanced release of proinflammatory factors and lung inflammation in a Mouse Hepatitis Virus (MHV) infection model. These findings elucidate a molecular mechanism driving coronavirus-induced hyperinflammation, proposing the E-TMED10 interaction as a potential therapeutic target to counteract the adverse effects of coronavirus-induced inflammation.

SARS-CoV-2 is highly homologous to SARS-CoV. To date, the main protease (Mpro) of SARS-CoV-2 is regarded as an important drug target for the treatment of Coronavirus Disease 2019 (COVID-19). Some experiments confirmed that several HIV protease inhibitors present the inhibitory effects on the replication of SARS-CoV-2 by inhibiting Mpro. However, the mechanism of action has still not been studied very clearly. In this work, the interaction mechanism of four HIV protease inhibitors Darunavir (DRV), Lopinavir (LPV), Nelfinavir (NFV), and Ritonavire (RTV) targeting SARS-CoV-2 Mpro was explored by applying docking, molecular dynamics (MD) simulations, and MM–GBSA methods using the broad-spectrum antiviral drug Ribavirin (RBV) as the negative and nonspecific control. Our results revealed that LPV, RTV, and NFV have higher binding affinities with Mpro, and they all interact with catalytic residues His41 and the other two key amino acids Met49 and Met165. Pharmacophore model analysis further revealed that the aromatic ring, hydrogen bond donor, and hydrophobic group are the essential infrastructure of Mpro inhibitors. Overall, this study applied computational simulation methods to study the interaction mechanism of HIV-1 protease inhibitors with SARS-CoV-2 Mpro, and the findings provide useful insights for the development of novel anti-SARS-CoV-2 agents for the treatment of COVID-19.