High dose IFN- activates GAF to enhance expression of ISGF3 target genes in epithelial cells
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE161475 | GEO | 2021/03/05
REPOSITORIES: GEO
Similar Datasets
Project description:High dose IFN-훽 activates GAF to enhance expression of ISGF3 target genes in epithelial cells
| PRJNA678362 | ENA
Project description:Interferon β (IFN-β) signaling activates the transcription factor complex ISGF3 to induce gene expression programs critical for antiviral defense and host immune responses. It has also been observed that IFN-β activates a second transcription factor complex, γ-activated factor (GAF), but the significance of this coordinated activation is unclear. We report that in murine lung epithelial cells (MLE12) high doses of IFN-β indeed activate both ISGF3 and GAF, which bind to distinct genomic locations defined by their respective DNA sequence motifs. In contrast, low doses of IFN-β preferentially activate ISGF3 but not GAF. Surprisingly, in MLE12 cells GAF binding does not induce nearby gene expression even when strongly bound to the promoter. Yet expression of interferon stimulated genes is enhanced when GAF and ISGF3 are both active compared to ISGF3 alone. We propose that GAF may function as a dose-sensitive amplifier of ISG expression to enhance antiviral immunity and establish pro-inflammatory states.
| S-EPMC8062733 | biostudies-literature
Project description:Although the core type I and type II IFN signaling pathways are distinct, their expression profiles show considerable overlap and are difficult to discern. Using a genome-wide RNAseq-ChIPseq integrative approach, our results identify a novel class of IFN-I and IFN-II responsive genes that use ISRE and GAS composite sites to recruit STAT1 and STAT2-containing ISGF3 and GAF-like complexes and IRF1 for optimal expression. Moreover, they support the existence of an analogous transcriptional regulatory mechanism of IFNα and IFNγ inducible genes, in which STAT1 and STAT2-containing ISGF3 and GAF-like complexes and IRF1 are recruited to individual or combined ISRE and GAS composite sites in an IFN- and time-dependent manner. In addition, we present proof for the involvement of an ISRE and GAS composite-dependent regulatory system in IFN-activated positive feedback regulation of the STAT1, STAT2, IRF9 and IRF1 genes and long-term response to IFNs, which depends on phosphorylation and expression of ISGF3, IRF1 and GAF-like components. These findings provide further insight in the existence of a novel intracellular amplifier circuit that offer an explanation for the existing molecular and functional overlap between IFN-I and IFN-II activated ISG expression.
2023-05-04 | GSE221804 | GEO
Project description:Although the core type I and type II IFN signaling pathways are distinct, their expression profiles show considerable overlap and are difficult to discern. Using a genome-wide RNAseq-ChIPseq integrative approach, our results identify a novel class of IFN-I and IFN-II responsive genes that use ISRE and GAS composite sites to recruit STAT1 and STAT2-containing ISGF3 and GAF-like complexes and IRF1 for optimal expression. Moreover, they support the existence of an analogous transcriptional regulatory mechanism of IFNα and IFNγ inducible genes, in which STAT1 and STAT2-containing ISGF3 and GAF-like complexes and IRF1 are recruited to individual or combined ISRE and GAS composite sites in an IFN- and time-dependent manner. In addition, we present proof for the involvement of an ISRE and GAS composite-dependent regulatory system in IFN-activated positive feedback regulation of the STAT1, STAT2, IRF9 and IRF1 genes and long-term response to IFNs, which depends on phosphorylation and expression of ISGF3, IRF1 and GAF-like components. These findings provide further insight in the existence of a novel intracellular amplifier circuit that offer an explanation for the existing molecular and functional overlap between IFN-I and IFN-II activated ISG expression.
2023-05-04 | GSE222667 | GEO
Project description:Exposure of macrophages to cytokines and pathogen-associated molecular patterns (PAMPs) can alter their subsequent stimulus responses, in part by epigenetic reprogramming. Our previous studies identified dynamic control of NFκB as a specificity mechanism for inducing hundreds of de novo enhancers in murine macrophages. A second set of hundreds of de novo enhancers are associated with the ISRE DNA binding element of the family of interferon regulatory factors (IRFs). In this project, we have dissected the roles of three endotoxin-responsive IRFs in macrophage de novo enhancer formation. While IRF3 was previously hypothesized to be a chromatin remodeling transcription factor, we found that its genetic requirement for enhancer formation (H3K4me1) is indirect, mediated by its role in type I IFN expression which activates the IRF9-containing ISGF3 transcription factor. However, our analysis shows that ISGF3 is unable to trigger enhancer formation on its own – it must cooperate with IRF1. Timecourse analysis of chromatin accessibility by ATAC-seq reveals that IRF1 plays a major role in the early steps of nucleosome eviction, while its partner ISGF3 then reinforces eviction and H3K4me1 deposition on neighboring nucleosomes. Further studies revealed that IRF1 can also cooperate with the type II IFN-induced GAF transcription factor, generating an additional set of IRF1-GAF-specific enhancers. Finally, global gene expression analysis by RNA-seq reveals that these IRF1-dependent enhancers are associated with potentiated expression of nearby genes in response to secondary immune threat exposure. Together our results reveal unexpected combinatorial coordination of IRF transcription factors in epigenomic reprograming to provide innate immune memory in a manner that is restricted to direct pathogen exposure or type II IFN-associated T-cell immunity, but not secondary innate immune stimulation via type I IFN.
2024-02-14 | GSE241819 | GEO
Project description:Exposure of macrophages to cytokines and pathogen-associated molecular patterns (PAMPs) can alter their subsequent stimulus responses, in part by epigenetic reprogramming. Our previous studies identified dynamic control of NFκB as a specificity mechanism for inducing hundreds of de novo enhancers in murine macrophages. A second set of hundreds of de novo enhancers are associated with the ISRE DNA binding element of the family of interferon regulatory factors (IRFs). In this project, we have dissected the roles of three endotoxin-responsive IRFs in macrophage de novo enhancer formation. While IRF3 was previously hypothesized to be a chromatin remodeling transcription factor, we found that its genetic requirement for enhancer formation (H3K4me1) is indirect, mediated by its role in type I IFN expression which activates the IRF9-containing ISGF3 transcription factor. However, our analysis shows that ISGF3 is unable to trigger enhancer formation on its own – it must cooperate with IRF1. Timecourse analysis of chromatin accessibility by ATAC-seq reveals that IRF1 plays a major role in the early steps of nucleosome eviction, while its partner ISGF3 then reinforces eviction and H3K4me1 deposition on neighboring nucleosomes. Further studies revealed that IRF1 can also cooperate with the type II IFN-induced GAF transcription factor, generating an additional set of IRF1-GAF-specific enhancers. Finally, global gene expression analysis by RNA-seq reveals that these IRF1-dependent enhancers are associated with potentiated expression of nearby genes in response to secondary immune threat exposure. Together our results reveal unexpected combinatorial coordination of IRF transcription factors in epigenomic reprograming to provide innate immune memory in a manner that is restricted to direct pathogen exposure or type II IFN-associated T-cell immunity, but not secondary innate immune stimulation via type I IFN.
2024-02-14 | GSE241818 | GEO
Project description:Exposure of macrophages to cytokines and pathogen-associated molecular patterns (PAMPs) can alter their subsequent stimulus responses, in part by epigenetic reprogramming. Our previous studies identified dynamic control of NFκB as a specificity mechanism for inducing hundreds of de novo enhancers in murine macrophages. A second set of hundreds of de novo enhancers are associated with the ISRE DNA binding element of the family of interferon regulatory factors (IRFs). In this project, we have dissected the roles of three endotoxin-responsive IRFs in macrophage de novo enhancer formation. While IRF3 was previously hypothesized to be a chromatin remodeling transcription factor, we found that its genetic requirement for enhancer formation (H3K4me1) is indirect, mediated by its role in type I IFN expression which activates the IRF9-containing ISGF3 transcription factor. However, our analysis shows that ISGF3 is unable to trigger enhancer formation on its own – it must cooperate with IRF1. Timecourse analysis of chromatin accessibility by ATAC-seq reveals that IRF1 plays a major role in the early steps of nucleosome eviction, while its partner ISGF3 then reinforces eviction and H3K4me1 deposition on neighboring nucleosomes. Further studies revealed that IRF1 can also cooperate with the type II IFN-induced GAF transcription factor, generating an additional set of IRF1-GAF-specific enhancers. Finally, global gene expression analysis by RNA-seq reveals that these IRF1-dependent enhancers are associated with potentiated expression of nearby genes in response to secondary immune threat exposure. Together our results reveal unexpected combinatorial coordination of IRF transcription factors in epigenomic reprograming to provide innate immune memory in a manner that is restricted to direct pathogen exposure or type II IFN-associated T-cell immunity, but not secondary innate immune stimulation via type I IFN.
2024-02-14 | GSE241817 | GEO
Project description:Virus infection induces the production of type I and type II interferons (IFN-I and IFN-II), cytokines that mediate the antiviral response. IFN-I (IFN-a and -b) induces the assembly of ISGF3 (interferon-stimulated gene factor 3), a multimeric transcriptional activation complex comprised of STAT1, STAT2 and IRF9. IFN-II (IFN-g) induces the homodimerization of STAT1 to form the GAF (gamma-activated factor) complex. ISGF3 and GAF bind specifically to distinct regulatory DNA sequences located upstream of IFN-I and II inducible genes, respectively, and activate the expression of distinct set of antiviral genes. The balance between the type I and type II IFN pathways plays a critical role in orchestrating the innate and adaptive immune systems. Here, we show that the phosphorylation of STAT1 by IKKε (IkB-related kinase epsilon) inhibits STAT1 homodimerization, and thus GAF formation, but does not disrupt ISGF3 formation. Therefore, virus and/or IFN-I activation of IKKε suppresses GAF-dependent transcription and promotes ISGF3-dependent transcription. In the absence of IKKε, GAF-dependent transcription is enhanced at the expense of ISGF3-mediated transcription, rendering cells less resistant to infection. We conclude that IKKε plays a critical role in regulating the balance between the IFN-I and IFN-II signaling pathways. ChIP-seq libraries were constructed with an antibody targeting STAT1 from bone marrow macrophages treated with interferon
2011-12-01 | E-GEOD-33913 | biostudies-arrayexpress
Project description:The Drosophila pioneer factor GAF is known to be essential for RNA Pol II promoter-proximal pausing and the removal of nucleosomes from a set of target promoters with GAGAG motifs. We and others have speculated that GAF recruits the ISWI family ATP-dependent chromatin remodeling complex NURF, on the basis that NURF and GAF are both required to remodel nucleosomes on an hsp70 promoter in vitro and that GAF interacts physically with NURF. However, GAF was also recently shown to interact with PBAP, a SWI/SNF family remodeler. To test which of these remodeling complexes GAF works with, we depleted GAF, NURF301, BAP170, and NURF301+BAP170 in Drosophila S2 cells using RNAi. We used a combination of PRO-seq, ATAC-seq, 3'RNA-seq, and CUT&RUN to demonstrate that while GAF and PBAP synergistically open chromatin at target promtoers which allows Pol II recruitment and pausing to proceed, GAF and NURF also synergistically position the +1 nucleosome to ensure efficient pause release and transition to productive elongation.
2020-09-01 | GSE157235 | GEO
Project description:Virus infection induces the production of type I and type II interferons (IFN-I and IFN-II), cytokines that mediate the antiviral response. IFN-I (IFN-a and -b) induces the assembly of ISGF3 (interferon-stimulated gene factor 3), a multimeric transcriptional activation complex comprised of STAT1, STAT2 and IRF9. IFN-II (IFN-g) induces the homodimerization of STAT1 to form the GAF (gamma-activated factor) complex. ISGF3 and GAF bind specifically to distinct regulatory DNA sequences located upstream of IFN-I and II inducible genes, respectively, and activate the expression of distinct set of antiviral genes. The balance between the type I and type II IFN pathways plays a critical role in orchestrating the innate and adaptive immune systems. Here, we show that the phosphorylation of STAT1 by IKKε (IkB-related kinase epsilon) inhibits STAT1 homodimerization, and thus GAF formation, but does not disrupt ISGF3 formation. Therefore, virus and/or IFN-I activation of IKKε suppresses GAF-dependent transcription and promotes ISGF3-dependent transcription. In the absence of IKKε, GAF-dependent transcription is enhanced at the expense of ISGF3-mediated transcription, rendering cells less resistant to infection. We conclude that IKKε plays a critical role in regulating the balance between the IFN-I and IFN-II signaling pathways.
2011-12-01 | GSE33913 | GEO