Similar Datasets
Project description:Genomic DNA folds into complex configurations that produce particular local and globalstructures thought to profoundly impact genome function. To understand the dynamic nature ofthis relationship, we investigated the extent of host chromatin structural and functional changesin response to a viral agent. We performed comprehensive assessments of host architecture (Hi-C), accessibility (ATAC-seq), and gene expression (RNA-seq) in a paired manner in response toattenuated vaccinia (smallpox) virus. Over time, infection significantly increased long-rangeintra-chromosomal interactions and decreased chromatin accessibility. Fine-scale accessibilitychanges were independent of broad-scale chromatin compartment exchange, which increased (upto 12% of the genome) over time, underscoring potential independent mechanisms for global andlocal chromatin reorganization. The majority of differentially expressed genes, including thosedownregulated in immune responses, had concurrent alterations in local accessibility and loopdomain restructuring. Increased B compartmentalization, intra-chromosomal interactions, anddecreased inter-chromosomal interactions and chromatin accessibility together indicate thatinfection converts the host genome into a more condensed state with nearly equal bidirectionaldifferential gene expression. These changes in host chromatin features may have implications fordeveloping efficacious anti-viral countermeasures. Overall, our empirical data provides evidenceof orchestrated concurrent alterations in chromatin architecture, accessibility, and geneexpression in response to infection, further reinforcing the notion of coordinated structurefunctiondynamics of the genome.
2024-05-07 | GSE248048 | GEO
Project description:Genomic DNA folds into complex configurations that produce particular local and globalstructures thought to profoundly impact genome function. To understand the dynamic nature ofthis relationship, we investigated the extent of host chromatin structural and functional changesin response to a viral agent. We performed comprehensive assessments of host architecture (Hi-C), accessibility (ATAC-seq), and gene expression (RNA-seq) in a paired manner in response toattenuated vaccinia (smallpox) virus. Over time, infection significantly increased long-rangeintra-chromosomal interactions and decreased chromatin accessibility. Fine-scale accessibilitychanges were independent of broad-scale chromatin compartment exchange, which increased (upto 12% of the genome) over time, underscoring potential independent mechanisms for global andlocal chromatin reorganization. The majority of differentially expressed genes, including thosedownregulated in immune responses, had concurrent alterations in local accessibility and loopdomain restructuring. Increased B compartmentalization, intra-chromosomal interactions, anddecreased inter-chromosomal interactions and chromatin accessibility together indicate thatinfection converts the host genome into a more condensed state with nearly equal bidirectionaldifferential gene expression. These changes in host chromatin features may have implications fordeveloping efficacious anti-viral countermeasures. Overall, our empirical data provides evidenceof orchestrated concurrent alterations in chromatin architecture, accessibility, and geneexpression in response to infection, further reinforcing the notion of coordinated structurefunctiondynamics of the genome.
2024-05-11 | GSE248050 | GEO
Project description:Genomic DNA folds into complex configurations that produce particular local and globalstructures thought to profoundly impact genome function. To understand the dynamic nature ofthis relationship, we investigated the extent of host chromatin structural and functional changesin response to a viral agent. We performed comprehensive assessments of host architecture (Hi-C), accessibility (ATAC-seq), and gene expression (RNA-seq) in a paired manner in response toattenuated vaccinia (smallpox) virus. Over time, infection significantly increased long-rangeintra-chromosomal interactions and decreased chromatin accessibility. Fine-scale accessibilitychanges were independent of broad-scale chromatin compartment exchange, which increased (upto 12% of the genome) over time, underscoring potential independent mechanisms for global andlocal chromatin reorganization. The majority of differentially expressed genes, including thosedownregulated in immune responses, had concurrent alterations in local accessibility and loopdomain restructuring. Increased B compartmentalization, intra-chromosomal interactions, anddecreased inter-chromosomal interactions and chromatin accessibility together indicate thatinfection converts the host genome into a more condensed state with nearly equal bidirectionaldifferential gene expression. These changes in host chromatin features may have implications fordeveloping efficacious anti-viral countermeasures. Overall, our empirical data provides evidenceof orchestrated concurrent alterations in chromatin architecture, accessibility, and geneexpression in response to infection, further reinforcing the notion of coordinated structurefunctiondynamics of the genome.
2024-05-11 | GSE248049 | GEO
Project description:Influenza A viruses (IAVs) use diverse mechanisms to interfere with cellular gene expression. Although many RNA-seq studies have documented IAV-induced changes in host mRNA abundance, few were designed to allow an accurate quantification of changes in host mRNA splicing. Here, we show that IAV infection of human lung cells induces widespread alterations of cellular splicing, with an overall increase in exon inclusion and decrease in intron retention. Over half of the mRNAs that show differential splicing undergo no significant changes in abundance or in their 3' end termination site, suggesting that IAVs can specifically manipulate cellular splicing. Among a randomly selected subset of 21 IAV-sensitive alternative splicing events, most are specific to IAV infection as they are not observed upon infection with VSV, induction of interferon expression or induction of an osmotic stress. Finally, the analysis of splicing changes in RED-depleted cells reveals a limited but significant overlap with the splicing changes in IAV-infected cells. This observation suggests that hijacking of RED by IAVs to promote splicing of the abundant viral NS1 mRNAs could partially divert RED from its target mRNAs. All our RNA-seq datasets and analyses are made accessible for browsing through a user-friendly Shiny interface (http://virhostnet.prabi.fr:3838/shinyapps/flu-splicing or https://github.com/cbenoitp/flu-splicing).
| S-EPMC7680258 | biostudies-literature
Project description:Influenza A viruses (IAV) use diverse mechanisms to interfere with cellular gene expression and thus limit the antiviral responses and/or promote viral replication. Although many RNAseq studies have documented IAV-induced changes in host mRNA abundance, few were designed to allow an accurate quantification of changes in host mRNA splicing. Here we show that IAV infection of human lung cells induces widespread alterations of cellular splicing, with an overall increase in exon inclusion and decrease in intron retention. Over half of the mRNAs that show differential splicing undergo no significant changes in abundance or in their 3’ end termination site, suggesting that IAV can directly manipulate cellular splicing independently of other transcriptional changes. Cross-analysis of the alternative splicing profiles of IAV-infected and RED-depleted cells demonstrates a partial phenocopying of the RED-knock down phenotype in infected cells, suggesting that hijacking of the RED factor by IAVs to promote splicing of their own mRNAs could account for a minor subset of splicing changes in infected cells. All our results can be expored through a Shiny user friendly interface (http://virhostnet.prabi.fr:3838/shinyapps/flu-splicing).
2020-08-31 | GSE154596 | GEO
Project description:Influenza virus infection induces widespread alterations of host cell splicing
| PRJNA646750 | ENA
Project description:DNA viruses can hijack and manipulate the host chromatin state to facilitate their infection. Multiple lines of evidences reveal that DNA virus infection results in the host chromatin relocation, yet there is little known about the effects of viral infection on the architecture of host chromatin. Here, a combination of epigenomic, transcriptomic and biochemical assays were conducted to investigate the temporal dynamics of chromatin accessibility in response to Bombyx mori nucleopolyhedrovirus (BmNPV) infection. The high-quality ATAC-seq data indicated that progressive chromatin remodeling took place following BmNPV infection. Viral infection resulted in a more open chromatin architecture, along with the marginalization of host genome and nucleosome disassembly. Moreover, our results revealed that chromatin accessibility in uninfected cells was regulated by euchromatic modifications, whereas the viral-induced highly accessible chromatin regions were originally associated with facultative heterochromatic modification. Overall, our findings illustrate for the first time the organization and accessibility of host chromatin in BmNPV-infected cells, which lay the foundation for future studies on epigenomic regulation mediated by DNA viruses.
| S-EPMC7326278 | biostudies-literature
Project description:Lytic infection with herpes simplex virus type 1 (HSV-1) induces profound modification of the cell nucleus including formation of a viral replication compartment and chromatin marginalization into the nuclear periphery. We used three-dimensional soft X-ray tomography, combined with cryogenic fluorescence, confocal and electron microscopy, to analyse the transformation of peripheral chromatin during HSV-1 infection. Our data showed an increased presence of low-density gaps in the marginalized chromatin at late infection. Advanced data analysis indicated the formation of virus-nucleocapsid-sized (or wider) channels extending through the compacted chromatin of the host. Importantly, confocal and electron microscopy analysis showed that these gaps frequently contained viral nucleocapsids. These results demonstrated that HSV-1 infection induces the formation of channels penetrating the compacted layer of cellular chromatin and allowing for the passage of progeny viruses to the nuclear envelope, their site of nuclear egress.
| S-EPMC5378911 | biostudies-literature
Project description:Interferons (IFNs) establish dynamic host defense mechanisms by inducing various IFN-stimulated genes that encodes many antiviral innate immune effectors. IFN-inducible transmembrane (IFITM) proteins have been identified as intrinsic antiviral effectors, which block the entry of a broad spectrum of enveloped RNA viruses by interrupting virus-endosomal fusion. However, antiviral activity of IFITM proteins against mammalian DNA virus has not been demonstrated till date. Here, we sought to investigate the antiviral activities and mechanisms of interferon-inducible transmembrane protein 3 (IFITM3) protein against poxvirus infection. Analysis of expression kinetics of cell endogenous IFITM3 protein indicated that vaccinia virus (VACV) infection suppressed its translation, which was independent of IRF3 phosphorylation triggered by VACV. Although silencing of endogenous IFITM proteins did not affect their baseline antiviral effects in the cell, it has reduced the IFN-α-mediated inhibition of VACV infection, and also modulated VACV-induced cell death. Moreover, we discovered that overexpression of IFITM3 significantly restricted VACV infection, replication and proliferation mainly by interfering with virus entry processes prior to the virus nucleocapsid entry into the cytoplasm. Interestingly, IFITM3 overexpression showed an impact on virus binding. Furthermore, IFITM3 interfered with the cytosolic entry of virus through low pH-dependent fashion. Taken together, our findings provide the first evidence of exogenously expressed IFITM3 protein restricting infection of an enveloped DNA virus, thus expanding their antiviral spectrum. This study further explores the complex mechanism and provides novel insights into the interaction between virus infection and host defense.
| S-EPMC5820317 | biostudies-literature
Project description:During migration, cells often squeeze through small constrictions, requiring extensive deformation. We hypothesized that nuclear deformation associated with such confined migration could alter chromatin organization and function. By studying cells migrating through microfluidic devices that mimic interstitial spaces in vivo, we found that confined migration results in increased H3K9me3 and H3K27me3 heterochromatin marks that persist for days. This "confined migration-induced heterochromatin" (CMiH) was distinct from heterochromatin formation during migration initiation. Confined migration decreased chromatin accessibility at intergenic regions near centromeres and telomeres, suggesting heterochromatin spreading from existing sites. Consistent with the overall decrease in accessibility, global transcription was decreased during confined migration. Intriguingly, we also identified increased accessibility at promoter regions of genes linked to chromatin silencing, tumor invasion, and DNA damage response. Inhibiting CMiH reduced migration speed, suggesting that CMiH promotes confined migration. Together, our findings indicate that confined migration induces chromatin changes that regulate cell migration and other functions.
| S-EPMC9474860 | biostudies-literature