Zika virus (ZIKV) infection remains a worldwide concern, and currently no effective treatments or vaccines are available. Novel therapeutics are an avenue of interest that could probe viral RNA-human protein communication to stop viral replication. One specific RNA structure, G-quadruplexes (G4s), possess various roles in viruses and all domains of life, including transcription and translation regulation and genome stability, and serves as nucleation points for RNA liquid-liquid phase separation. Previous G4 studies on ZIKV using a quadruplex forming G-rich sequences Mapper located a potential G-quadruplex sequence in the 3′ terminal region (TR) and was validated structurally using a 25-mer oligo. It is currently unknown if this structure is conserved and maintained in a large ZIKV RNA transcript and its specific roles in viral replication. Using bioinformatic analysis and biochemical assays, we demonstrate that the ZIKV 3′ TR G4 is conserved across all ZIKV isolates and maintains its structure in a 3′ TR full-length transcript. We further established the G4 formation using pyridostatin and the BG4 G4-recognizing antibody binding assays. Our study also demonstrates that the human DEAD-box helicases, DDX3X_132-607 and DDX17_135-555, bind to the 3′ TR and that DDX17_135-555 unfolds the G4 present in the 3′ TR. These findings provide a path forward in potential therapeutic targeting of DDX3X or DDX17’s binding to the 3′ TR G4 region for novel treatments against ZIKV.

Bats are recognized as natural reservoirs for an array of diverse viruses, particularly coronaviruses, which have been linked to major human diseases like SARS-CoV and MERS-CoV. These viruses are believed to have originated in bats, highlighting their role in virus ecology and evolution. Our study focuses on the molecular characterization of bat-derived coronaviruses (CoVs) in Canada. Tissue samples from 500 bat specimens collected in Canada were analyzed using pan-coronavirus RT-PCR assays to detect the presence of CoVs from four genera: Alpha-CoVs, Beta-CoV, Gamma-CoV, and Delta-CoV. Phylogenetic analysis was performed targeting the RNA-dependent RNA polymerase (RdRP) gene. Our results showed an overall 1.4% CoV positivity rate in our bat sample size. Phylogenetic analysis based on the ~600 bp sequences led to the identification of an unclassified subgenus of Alpha-CoV, provisionally named Eptacovirus. The findings contribute to a better understanding of the diversity and evolution of CoVs found in the bat species of Canada. The current study underscores the significance of bats in the epidemiology of CoVs and enhances the knowledge of their genetic diversity and potential impact on global public health.

Human zyxin is a key component of the focal adhesion complex, playing a role in mediating cell–cell adhesion and cytoskeletal dynamics. Moreover, zyxin shuttles between the cytoplasm and the nucleus, where it contributes to regulating gene expression. Although identified over 30 years ago, zyxin’s nuclear functions, particularly in relation to cancer, remain largely unexplored. In this study, we profiled zyxin binding to chromosomal DNA using metastatic prostate carcinoma PC3M cells as a model. Our ChIP-Seq results revealed that zyxin binds to chromosomal DNA, with mitochondrial pseudogenes as the primary targets. Furthermore, we demonstrated that the LIM domains of zyxin are sufficient for DNA binding and that zyxin knockdown leads to transcriptional changes in mitochondrial pseudogenes. Additionally, zyxin knockdown impacted several other genes associated with mitochondrial integrity and apoptosis, resulting in disturbances in MTCO2P2 RNA localization, mitochondrial membrane potential, increased reactive oxygen species, alterations in the cell cycle, and progression towards apoptosis. Overall, our work shows that zyxin directly interacts with nuclear DNA and regulates the transcription of mitochondrial pseudogenes, emphasizing its role in modulating mitochondrial function.

Here, using small angle X-ray scattering (SAXS) data profile as reference, we attempted to visualize conformational ensemble accessible prefibrillar monomeric state of α-synuclein in solution. In agreement with previous reports, our analysis also confirmed that α-synuclein molecules adopted disordered shape profile under non-associating conditions. Chain-ensemble modeling protocol with dummy residues provided two weighted averaged clusters of semi-extended shapes. Further, Ensemble Optimization Method (EOM) computed mole fractions of semi-extended “twisted” conformations which might co-exist in solution. Since these were only C ^α traces of the models, ALPHAFOLD2 server was used to search for all-atom models. Comparison with experimental data showed all predicted models disagreed equally, as individuals. Finally, we employed molecular dynamics simulations and normal mode analysis-based search coupled with SAXS data to seek better agreeing models. Overall, our analysis concludes that a shifting equilibrium of curved models with low α-helical content best-represents non-associating monomeric α-synuclein.