Mus musculus
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ABSTRACT:
PROVIDER: PRJNA311545 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Protracted NP95 binding to hemimethylated DNA disrupts SETDB1-mediated proviral silencing
| PRJNA311541 | ENA
Project description:Protracted NP95 binding to hemimethylated DNA disrupts SETDB1-mediated proviral silencing [RRBS-seq]
| PRJNA311543 | ENA
Project description:Protracted NP95 binding to hemimethylated DNA disrupts SETDB1-mediated proviral silencing [ChIP-seq]
| PRJNA311544 | ENA
Project description:Genetic ablation of the maintenance methyltransferase Dnmt1 induces widespread demethylation and transcriptional activation of CpG-rich IAP (intracisternal A particle) proviruses. Here, we report that this phenomenon is not simply a consequence of loss of DNA methylation. By exploiting conditional deletions of Dnmt1 and Np95, each of which is essential for maintenance methylation, we find that while IAPs are indeed de-repressed in Dnmt1-ablated embryos and embryonic stem cells (ESCs), these proviruses remain silenced in Np95-ablated cells, despite similar kinetics of passive demethylation. Paradoxically, transient IAP activation in Dnmt1-ablated ESCs requires the presence of NP95. We subsequently show that in the absence of NP95, the H3K9 methyltransferase SETDB1 maintains IAP silencing; while in the absence of DNMT1, prolonged binding of NP95 to hemimethylated DNA perturbs SETDB1-dependent H3K9me3 deposition. Taken together, these observations reveal that following acute loss of Dnmt1, H3K9 methylation-dependent IAP silencing is disrupted by aberrant NP95 binding to hemimethylated DNA. RNA-seq for Np95, Dnmt1 and Setdb1 wt, single conditional KO (cKO) and double cKO ES cells; RRBS-seq for Dnmt1 and Np95 single and double cKO ESCs; Myc-tagged NP95, DNMT1 ChIP-seq; and wt and Np95wt and cKO H3K9me3 ChIP-seq.
2016-04-06 | E-GEOD-77778 | biostudies-arrayexpress
Project description:The repression of transposable elements in eukaryotes often involves their transcriptional silencing via targeted chromatin modifications. In animal gonads, nuclear Argonaute proteins of the PIWI-clade complexed with small guide RNAs (piRNAs) serve as sequence specificity determinants in this process. How binding of nuclear PIWI-piRNA complexes to nascent transcripts orchestrates heterochromatin formation and transcriptional silencing is unknown. Here, we characterize CG9754/Silencio as an essential piRNA pathway factor that is required for Piwi-mediated transcriptional silencing in Drosophila. Ectopic targeting of Silencio to RNA or DNA is sufficient to elicit silencing independent of Piwi and known piRNA pathway factors. Instead, Silencio requires the H3K9 methyl-transferase Eggless/SetDB1 for its silencing ability. In agreement with this, SetDB1 but not Su(var)3-9 is required for Piwi-mediated transcriptional silencing genome-wide. Due to its interaction with the target-engaged Piwi-piRNA complex we suggest that Silencio acts as linker between the sequence specificity factor Piwi and the cellular heterochromatin machinery.
2015-11-19 | GSE74097 | GEO
Project description:Transcription of endogenous retroviruses (ERVs) is inhibited by de novo DNA methylation during gametogenesis, a process initiated after birth in oocytes and at ~E15.5 in prospermatogonia. Earlier in germline development however, the genome, including most retrotransposons, is progressively demethylated, with young ERVK and ERV1 elements retaining intermediate methylation levels. As DNA methylation reaches a low point in E13.5 primordial germ cells (PGCs) of both sexes, we determined whether retrotransposons are marked by H3K9me3 and H3K27me3 using a recently developed low input ChIP-seq method. Although these repressive histone modifications are predominantly found on distinct genomic regions in E13.5 PGCs, they concurrently mark partially methylated LTRs and LINE1 elements. Germline-specific conditional knock-out (KO) of the H3K9 methyltransferase SETDB1 yields a decrease of both histone marks and DNA methylation at H3K9me3 enriched retrotransposon families. Strikingly, Setdb1-KO E13.5 PGCs show concomitant de-repression of many marked ERVs, including IAP, ETn and ERVK10C elements and ERV-proximal genes, a subset in a sex-dependent manner. Furthermore, Setdb1 deficiency is associated with a reduced number of male PGCs and postnatal hypogonadism in both sexes. Taken together, these observations reveal that SETDB1 is an essential guardian against proviral expression prior to the onset of de novo DNA methylation in the germline. H3K9me3, H3K27me3 and expression profiles in Setdb1 WT, Het and KO male and female E13.5 PGCs.
2014-09-01 | E-GEOD-60377 | biostudies-arrayexpress
Project description:Only a small percentage of human transcription factors (e.g. those associated with a specific differentiation program) are expressed in a given cell type. Thus, cell fate is mainly determined by cell type-specific silencing of transcription factors that drive different cellular lineages. Several histone modifications have been associated with gene silencing, including H3K27me3 and H3K9me3. We have previously shown that the two largest classes of mammalian transcription factors are marked by distinct histone modifications; homeobox genes are marked by H3K27me3 and zinc finger genes are marked by H3K9me3. Several histone methyltransferases (e.g. G9a and SETDB1) may be involved in mediating the H3K9me3 silencing mark. We have used ChIP-chip (GSE24480) and ChIP-seq to demonstrate that SETDB1, but not G9a, is associated with regions of the genome enriched for H3K9me3. A current model is that SETDB1 is recruited to specific genomic locations via interaction with the corepressor TRIM28 (KAP1), which is in turn recruited to the genome via interaction with zinc finger transcription factors that contain a Kruppel-associated box (KRAB) domain. However, specific KRAB-ZNFs that recruit TRIM28 (KAP1) and SETDB1 to the genome have not been identified. We now show that ZNF274 (a KRAB-ZNF that contains 5 C2H2 zinc finger domains), can interact with KAP1 in vitro and, using ChIP-seq, we show that ZNF274 binding sites co-localize with SETDB1, KAP1, and H3K9me3 at the 3’ ends of zinc finger genes. Knockdown of ZNF274 with siRNAs reduced the levels of KAP1 and SETDB1 recruitment to the binding sites. These studies provide the first identification of a KRAB domain-containing ZNFs that is involved in recruitment of the KAP1 and SETDB1 to the human genome. For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf 7 total ChIP-seq datasets; 4 ZNF274 datasets done in duplicate from 4 different cell lines; 1 KAP1 duplicate dataset done in duplicate from K562 cells; 1 SetDB1 duplicate dataset from K562 cells; 1 H3K9me3 duplicate dataset from K562 cells
2010-11-15 | E-GEOD-24632 | biostudies-arrayexpress
Project description:Only a small percentage of human transcription factors (e.g. those associated with a specific differentiation program) are expressed in a given cell type. Thus, cell fate is mainly determined by cell type-specific silencing of transcription factors that drive different cellular lineages. Several histone modifications have been associated with gene silencing, including H3K27me3 and H3K9me3. We have previously shown that the two largest classes of mammalian transcription factors are marked by distinct histone modifications; homeobox genes are marked by H3K27me3 and zinc finger genes are marked by H3K9me3. Several histone methyltransferases (e.g. G9a and SETDB1) may be involved in mediating the H3K9me3 silencing mark. We have used ChIP-chip and ChIP-seq (GSE24632) to demonstrate that SETDB1, but not G9a, is associated with regions of the genome enriched for H3K9me3. A current model is that SETDB1 is recruited to specific genomic locations via interaction with the corepressor TRIM28 (KAP1), which is in turn recruited to the genome via interaction with zinc finger transcription factors that contain a Kruppel-associated box (KRAB) domain. However, specific KRAB-ZNFs that recruit TRIM28 (KAP1) and SETDB1 to the genome have not been identified. We now show that ZNF274 (a KRAB-ZNF that contains 5 C2H2 zinc finger domains), can interact with KAP1 in vitro and, using ChIP-seq, we show that ZNF274 binding sites co-localize with SETDB1, KAP1, and H3K9me3 at the 3â ends of zinc finger genes. Knockdown of ZNF274 with siRNAs reduced the levels of KAP1 and SETDB1 recruitment to the binding sites. These studies provide the first identification of a KRAB domain-containing ZNFs that is involved in recruitment of the KAP1 and SETDB1 to the human genome. This study includes the 4 ChIP-chip arrays only.
2010-11-01 | E-GEOD-24480 | biostudies-arrayexpress
Project description:Purpose: The aim of this study is (1) to identify the chromatin occupancy of the epigenetic regulator Setdb1 in mouse embryonic fibroblasts (MEF); (2) to profile key epigenetic marks H3K9me2, H3K9me3 and H3K27me3; utilizing wildtype cells with nonsilencing shRNA mediated knockdown and Setdb1 geneTrap heterozygous cells with Setdb1 shRNA mediated knockdown. Methods: Chromatin immunoprecipitation for Setdb1, H3K9me2, H3K9me3 and H3K27me3 was performed essentially as in (Nelson et al. 2006). Briefly, nuclei were isolated from formaldehyde crosslinked MEFs and chromatin was fragmented by sonication. Chromatin immunoprecipitation was performed with corresponding antibodies for Setdb1, H3K9me2, H3K9me3 and H3K27me3. DNA was extracted from the immunoprecipitated fraction following reverse-crosslinking. Isolated DNA was used to generate sequencing libraries with Illumina's TruSeq DNA Sample Preparation Kit according to manufacturer's instruction. Libraries were pooled and sequenced on the Illumina HiSeq 2000 platform for 100 bp single-end reads. Image analysis was performed in real time by the HiSeq Control Software (HCS) v1.4.8 and Real Time Analysis (RTA) v1.12.4.2, running on the instrument computer. Real-time base calling on the HiSeq instrument computer was performed with the RTA software. Illumina CASAVA1.8 pipeline was used to generate the sequence data. Chromatin occupancy of the epigenetic regulator Setdb1, H3K9me2, H3K9me3 and H3K27me3 in mouse embryonic fibroblasts (MEFs) with wildtype MEFs and nonsilencing shRNA mediated knockdown or Setdb1 geneTrap heterozygous MEFs with Setdb1 shRNA mediated knockdown was determined by Setdb1, H3K9me2, H3K9me3 and H3K27me3 ChIP-seq, respectively.
2016-05-18 | E-GEOD-66522 | biostudies-arrayexpress
Project description:Silencing of endogenous retroviruses (ERVs) is largely mediated by repressive chromatin modifications, such as H3K9me3 and DNA methylation. Their impact on ERV silencing differs in various cell types and, no systematic analyses on the interdependence between H3K9me3 and DNA methylation have been performed in differentiated cells. Here we show that deletion of the H3K9me3 HMTase Setdb1 in mouse embryonic endoderm results in ERV de-repression in only a subset of endoderm cells. We found that de-repression is restricted to visceral endoderm descendants and does not occur in definitive endoderm cells. Deletion of Setdb1 in visceral endoderm progenitors resulted in loss of H3K9me3 and reduced DNA methylation of IAPEz, consistent with up-regulation of this ERV family. In definitive endoderm cells, loss of Setdb1 did not affect H3K9me3 nor DNA methylation, suggesting Setdb1-independent pathways for maintaining these modifications. Importantly, Dnmt1 ko resulted in ERV de-repression in both visceral and definitive endoderm cells, while H3K9me3 was unaltered. Thus, our data suggest a dominant role of DNA methylation over H3K9me3 in ERV silencing in endoderm cells. Our findings suggest, that H3K9me3 is not sufficient for ERV silencing, but rather critical for maintaining high DNA methylation.
2022-08-01 | GSE169464 | GEO