RIF1 and KAP1 differentially regulate the choice of inactive versus active X chromosomes
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA695506 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:We have investigated the effect acute deletion of Rif1 has on the transcriptome in mESC and during early stage differentiation.
2021-11-04 | GSE165704 | GEO
Project description: Not available
| S-SCDT-EMBOJ-2020-105862 | biostudies-other
Project description:RIF1 acts downstream of 53BP1 to coordinate DNA double strand break repair pathway choice between non-homologous end joining (NHEJ) and homologous recombination (HR). Here we identified ASF1 as an endogenous RIF1-associated protein. We showed that ASF1 forms complex with RIF1 and regulates RIF1-dependent functions in DNA damage response.
2022-06-09 | PXD027727 | Pride
Project description:Rif1 is involved in telomere homeostasis, DNA replication timing, and DNA double-strand break (DSB) repair pathway choice from yeast to human. The molecular mechanisms that enable Rif1 to fulfill its diverse roles remain to be determined. Here, we demonstrate that Rif1 is S-acylated within its conserved N-terminal domain at cysteine residues C466 and C473 by the DHHC family palmitoyl acyltransferase Pfa4. Rif1 S-acylation facilitates the accumulation of Rif1 at DSBs, the attenuation of DNA end-resection, and DSB repair by non-homologous end-joining (NHEJ). These findings identify S-acylation as a posttranslational modification regulating DNA repair. S-acylated Rif1 mounts a localized DNA-damage response proximal to the inner nuclear membrane, revealing a mechanism of compartmentalized DSB repair pathway choice by sequestration of a fatty acylated repair factor at the inner nuclear membrane.
2019-04-15 | PXD012137 | Pride
Project description:X chromosome inactivation (XCI) is a dosage compensation mechanism that silences the majority of genes on one X chromosome in each female cell. In order to characterize epigenetic changes that accompany this process, we measured DNA methylation levels in both 45,X Turner syndrome patients, who carry a single active X chromosome (Xa) and normal 46,XX females, who carry one Xa and one inactive X (Xi). Methylated DNA was immunoprecipitated and hybridized to tiling oligonucleotide arrays, generating epigenetic profiles of active and inactive X chromosomes. We observed that XCI is accompanied by changes in DNA methylation specifically at CpG islands. While the majority of CpG islands show increased methylation levels on the Xi, XCI results in reduced methylation at ~20% of CpG islands. Both intra- and inter-genic CpG islands are epigenetically modified, with the biggest increase in methylation occuring at the promoters of genes silenced by XCI. In contrast, genes escaping XCI have low levels of promoter methylation, while genes that undergo polymorphic silencing show intermediate increases in methylation proportionate to their frequency of inactivation. Thus promoter methylation and susceptibility to XCI are correlated. We observed a global correlation between CpG island methylation and the evolutionary age of different X chromosome strata, and that genes escaping XCI show increased methylation within gene bodies. We utilized our epigenetic map to predict both novel genes escaping XCI, and to identify sequence features that may contribute to the XCI process. Finally, as our study included Turner syndrome patients with single X chromosomes of both maternal and paternal origin we searched for parent-of-origin specific methylation differences, but found no evidence to support imprinting on the human X chromosome. Our study provides the first epigenetic profile of active and inactive X chromosomes, giving novel insights into the phenomenon of dosage compensation. Methylated DNA was enriched by immunoprecipitation using antibodies against 5-methylcytosine. meDIP and input DNA was labeled with cy5 and cy3 respectively and hybridized to Nimblegen arrays comprising 2.1 million 50-85mers covering human chromosomes 20, 21, 22, X and Y at a mean density of ~1 probe per 100bp. Resulting log2 fluorescence ratios correspond to methylation levels. Seven patients with Turner syndrome (45,X karyotype), and three normal females (46,XX karyotype) were analyzed. Of the Turner syndrome cases, four had a maternally-derived X, and three had a paternally-derived X chromosome.
2010-07-20 | E-GEOD-22551 | biostudies-arrayexpress
Project description:One of the long-standing questions in eukaryotic DNA replication is the mechanisms that determine where and when a particular segment of the genome is replicated. Cdc7/Hsk1 is a conserved kinase required for initiation of DNA replication, and may affect the site selection and timing of origin firing. We identified rif1∆, a null mutant of rif1+, a conserved telomere binding factor, as an efficient bypass mutant of fission yeast hsk1. Extensive deregulation of dormant origins over a wide range of the chromosomes occurs in rif1∆ in the presence or absence of HU. At the same time, many early-firing, efficient origins are suppressed or delayed in firing timing in rif1∆. Rif1 binds not only to telomeres but also to many specific locations on the arm segments that only partially overlap with the pre-Replicative Complex assembly sites, although Rif1 tends to bind in the vicinity of the late/ dormant origins activated in rif1∆. The binding to the arm segments occurs through M to G1 phase in a manner independent of Taz1 and appears to be essential for the replication timing program during normal cell cycle. Our data demonstrate that Rif1 is a critical determinant of origin activation program on the fission yeast chromosomes. BrdU incorporation profiles at early S-phase in Wild vs rif1∆. Cdc45 binding profiles at early S-phase in Wild vs rif1∆. Rif1 binidng sites aroud G1/S boudary and at M-phase. Mcm4 binding sites in wild, hsk1-89 temperature mutant and rif1∆.
2011-12-13 | GSE34369 | GEO
Project description:X chromosome inactivation (XCI) is a dosage compensation mechanism that silences the majority of genes on one X chromosome in each female cell. In order to characterize epigenetic changes that accompany this process, we measured DNA methylation levels in both 45,X Turner syndrome patients, who carry a single active X chromosome (Xa) and normal 46,XX females, who carry one Xa and one inactive X (Xi). Methylated DNA was immunoprecipitated and hybridized to tiling oligonucleotide arrays, generating epigenetic profiles of active and inactive X chromosomes. We observed that XCI is accompanied by changes in DNA methylation specifically at CpG islands. While the majority of CpG islands show increased methylation levels on the Xi, XCI results in reduced methylation at ~20% of CpG islands. Both intra- and inter-genic CpG islands are epigenetically modified, with the biggest increase in methylation occuring at the promoters of genes silenced by XCI. In contrast, genes escaping XCI have low levels of promoter methylation, while genes that undergo polymorphic silencing show intermediate increases in methylation proportionate to their frequency of inactivation. Thus promoter methylation and susceptibility to XCI are correlated. We observed a global correlation between CpG island methylation and the evolutionary age of different X chromosome strata, and that genes escaping XCI show increased methylation within gene bodies. We utilized our epigenetic map to predict both novel genes escaping XCI, and to identify sequence features that may contribute to the XCI process. Finally, as our study included Turner syndrome patients with single X chromosomes of both maternal and paternal origin we searched for parent-of-origin specific methylation differences, but found no evidence to support imprinting on the human X chromosome. Our study provides the first epigenetic profile of active and inactive X chromosomes, giving novel insights into the phenomenon of dosage compensation.
2010-07-20 | GSE22551 | GEO
Project description:Rif1 regulates replication timing and repair of double-stranded DNA breaks. Using Chromatin-immunoprecipitation-Sequencing method, we have identified 35 high-affinity Rif1 binding sites in fission yeast chromosomes. Binding sites, preferentially located to the vicinity of dormant origins, tended to contain at least two copies of a conserved motif, CNWWGTGGGGG, and base substitution within these motifs resulted in complete loss of Rif1 binding and activation of late-firing or dormant origins located as far as 50 kb away. We show that Rif1 binding sites adopt G-quadruplex-like structures in vitro in a manner dependent on the conserved sequence as well as on other G-tracts, and that the purified Rif1 preferentially binds to this structure. These results suggest that Rif1 recognizes and binds to G-quadruplex-like structures at selected intergenic regions to generate local chromatin structures that may exert a long-range suppressive effects on origin firing. ChIP-Seq profiles of Rif1 and DNA replicaiton (BrdU-incorporation) vs Input in wildt type, rap1∆, taz1∆, Rif1BS mutants and rif1∆
2015-09-10 | E-GEOD-65293 | biostudies-arrayexpress
Project description:Rif1 regulates replication timing and repair of double-stranded DNA breaks. Using Chromatin-immunoprecipitation-Sequencing method, we have identified 35 high-affinity Rif1 binding sites in fission yeast chromosomes. Binding sites, preferentially located to the vicinity of dormant origins, tended to contain at least two copies of a conserved motif, CNWWGTGGGGG, and base substitution within these motifs resulted in complete loss of Rif1 binding and activation of late-firing or dormant origins located as far as 50 kb away. We show that Rif1 binding sites adopt G-quadruplex-like structures in vitro in a manner dependent on the conserved sequence as well as on other G-tracts, and that the purified Rif1 preferentially binds to this structure. These results suggest that Rif1 recognizes and binds to G-quadruplex-like structures at selected intergenic regions to generate local chromatin structures that may exert a long-range suppressive effects on origin firing.
2015-09-10 | GSE65293 | GEO
Project description:The ATP dependent chromatin remodeler SMARCAD1 and the co-repressor KAP1 (Trim28/Tif1 beta) interact directly. We wanted to understand the interplay between these two proteins in the context of chromatin; in particular at repetitive sequences. Therefore, we carried out an investigation in E14 ES cells of the genome wide binding behaviour of KAP1 and FLAG-tagged SMARCAD1; both wild-type SMARCAD1 and a catalytically inactive mutant. The E14 cells analysed were either wild-type or depleted for endogenous SMARCAD1 protein. FLAG and KAP1 ChIP was performed on double-cross linked chromatin and sequenced on an Illumina HiSeq1500 with matched input controls. A FLAG antibody precipitation was carried out on cells not expressing FLAG tagged protein as an additional control.
2019-02-17 | E-MTAB-7011 | biostudies-arrayexpress