Set1/COMPASS repels heterochromatin invasion at euchromatic sites by disrupting Suv39/Clr4 activity and nucleosome stability
Ontology highlight
ABSTRACT:
ORGANISM(S): Schizosaccharomyces pombe
PROVIDER: GSE140067 | GEO | 2020/08/24
REPOSITORIES: GEO
Similar Datasets
Project description:Protection of euchromatin from invasion by gene-repressive heterochromatin is critical for cellular health and viability. In addition to constitutive loci such as pericentromeres and subtelomeres, heterochromatin can be found interspersed in gene-rich euchromatin, where it regulates gene expression pertinent to cell fate. While heterochromatin and euchromatin are globally poised for mutual antagonism, the mechanisms underlying precise spatial encoding of heterochromatin containment within euchromatic sites remain opaque. We investigated ectopic heterochromatin invasion by manipulating the fission yeast mating type locus boundary using a single-cell spreading reporter system. We found that heterochromatin repulsion is locally encoded by Set1/COMPASS on certain actively transcribed genes and that this protective role is most prominent at heterochromatin islands, small domains interspersed in euchromatin that regulate cell fate specifiers. Sensitivity to invasion by heterochromatin, surprisingly, is not dependent on Set1 altering overall gene expression levels. Rather, the gene-protective effect is strictly dependent on Set1's catalytic activity. H3K4 methylation, the Set1 product, antagonizes spreading in two ways: directly inhibiting catalysis by Suv39/Clr4 and locally disrupting nucleosome stability. Taken together, these results describe a mechanism for spatial encoding of euchromatic signals that repel heterochromatin invasion.
| S-EPMC6938669 | biostudies-literature
Project description:Set1/COMPASS repels heterochromatin invasion at euchromatic sites by disrupting Suv39/Clr4 activity and nucleosome stability
| PRJNA588170 | ENA
Project description:The stimulation of trimethylation of histone H3 lysine 4 (H3K4) by H2B monoubiquitination (H2Bub) has been widely studied with multiple mechanisms proposed for this form of histone crosstalk. Cps35/Swd2 within COMPASS is considered to bridge these processes. However, a truncated form of Set1 (762-Set1) is reported to function in H3K4 trimethylation without interacting with Cps35/Swd2, and such crosstalk is attributed to the n-SET domain of Set1 and its interaction with the Cps40/Spp1 subunit of COMPASS. Here, we use biochemical, structural, in vivo, and ChIP-seq approaches to demonstrate that Cps40/Spp1 and the n-SET domain of Set1 are required for the stability of Set1 and not the crosstalk. Furthermore, the apparent wild-type levels of H3K4 trimethylation (H3K4me3) in the 762-Set1 strain is due to rogue methylase activity of this mutant resulting in the mislocalization of H3K4me3 from the promoter-proximal regions to gene bodies and intergenic regions. We have also performed detailed screens and identified yeast strains lacking H2Bub, but containing intact H2Bub enzymes, that have normal levels of H3K4me3, suggesting that ubiquitination may not directly stimulate COMPASS, but rather works in a context of the PAF and Rad6/Bre1 complexes. Our study demonstrates that the ubiquitination machinery and Cps35/Swd2 function to focus COMPASS’ H3K4me3 activity at promoter-proximal regions in a context dependent manner. ChIP-Seq for H3K4ME3 in S. cerevisie wild-type strains and strains expressing a truncated form of Set1: aa762-1080 Set1. H3K4ME3 ChIP-Seq was also compared for wild-type, leo1 knockout, and chd1 knockout strains
2014-01-09 | E-GEOD-53241 | biostudies-arrayexpress
Project description:The stimulation of trimethylation of histone H3 lysine 4 (H3K4) by H2B monoubiquitination (H2Bub) has been widely studied with multiple mechanisms proposed for this form of histone crosstalk. Cps35/Swd2 within COMPASS is considered to bridge these processes. However, a truncated form of Set1 (762-Set1) is reported to function in H3K4 trimethylation without interacting with Cps35/Swd2, and such crosstalk is attributed to the n-SET domain of Set1 and its interaction with the Cps40/Spp1 subunit of COMPASS. Here, we use biochemical, structural, in vivo, and ChIP-seq approaches to demonstrate that Cps40/Spp1 and the n-SET domain of Set1 are required for the stability of Set1 and not the crosstalk. Furthermore, the apparent wild-type levels of H3K4 trimethylation (H3K4me3) in the 762-Set1 strain is due to rogue methylase activity of this mutant resulting in the mislocalization of H3K4me3 from the promoter-proximal regions to gene bodies and intergenic regions. We have also performed detailed screens and identified yeast strains lacking H2Bub, but containing intact H2Bub enzymes, that have normal levels of H3K4me3, suggesting that ubiquitination may not directly stimulate COMPASS, but rather works in a context of the PAF and Rad6/Bre1 complexes. Our study demonstrates that the ubiquitination machinery and Cps35/Swd2 function to focus COMPASS’ H3K4me3 activity at promoter-proximal regions in a context dependent manner.
2014-01-09 | GSE53241 | GEO
Project description:Changes in histone post-translational modifications are associated with aging through poorly defined mechanisms. Histone 3 lysine 4 (H3K4) methylation at promoters is deposited by SET1 family methyltransferases acting within conserved multiprotein complexes known as COMPASS. Using co-immunopurification coupled to mass spectrometry-based proteomics, we characterized complex members and binding partners in various genetic contexts, using WDR-5 or CFP-1 proteins as baits.
2021-12-08 | PXD029904 | Pride
Project description:Methylation of histone H3 lysine 4 (H3K4) by the Set1/COMPASS complex is coupled with active transcription, and this modification is important for regulating gene expression. Set1/COMPASS associates with the RNA polymerase II (RNApII) C-terminal domain (CTD) to establish proper levels and distribution of H3K4 methylations.To ask how the Set1-RNApII CTD binding affects the occupancy and overall level of H3K4 methylations, ChIP-Seq was pefromed in cells transformed with full length or N-terminal truncated Set1. Our results indicate that Set1-RNApII CTD interaction is necessary for maintaining H3K4 methylations throughout the genes.
2019-10-02 | GSE138281 | GEO
Project description:TET proteins convert 5-methylcytosine to 5-hydroxymethylcytosine, an emerging dynamic epigenetic state of DNA that can influence transcription. Evidence has linked TET1 function to epigenetic repression complexes, yet mechanistic information, especially for the TET2 and TET3 proteins, remains limited. Here, we show a direct interaction of TET2 and TET3 with O-GlcNAc transferase (OGT). OGT does not appear to influence hmC activity, rather TET2 and TET3 promote OGT activity. TET2/3-OGT co-localize on chromatin at active promoters enriched for H3K4me3 and reduction of either TET2/3 or OGT activity results in a direct decrease in H3K4me3 and concomitant decreased transcription. Further, we show that Host Cell Factor 1 (HCF1), a component of the H3K4 methyltransferase SET1/COMPASS complex, is a specific GlcNAcylation target of TET2/3-OGT, and modification of HCF1 is important for the integrity of SET1/COMPASS. Additionally, we find both TET proteins and OGT activity promote binding of the SET1/COMPASS H3K4 methyltransferase, SETD1A, to chromatin. Finally, studies in Tet2 knockout mouse bone marrow tissue extend and support the data as decreases are observed of global GlcNAcylation and also of H3K4me3, notably at several key regulators of haematopoiesis. Together, our results unveil a step-wise model, involving TET-OGT interactions, promotion of GlcNAcylation, and influence on H3K4me3 via SET1/COMPASS, highlighting a novel means by which TETs may induce transcriptional activation. ChIP-Seq experiments were performed on Illumina HiScanSQ sequencer in wild-type HEK293T cells for H3K4me3 histone marks, O-GlcNAc and HCF1, for HT-TET2, HT-TET3 and HT-OGT in HEK293T cells overexpressing those three fusion proteins and in TET2 Kd HEK293T cells for H3K4me3 histone marks. ChIP-Seqs were also performed in mouse bone marrow tissues for H3K4me3 histone marks, O-GlcNAc, endogenous Tet2 and in Tet2 Ko bone marrow tissues for H3K4me3 histone marks.
2013-02-07 | E-GEOD-36620 | biostudies-arrayexpress
Project description:Eukaryotic chromatin is organized into either silenced heterochromatin or relaxed euchromatin regions, which controls the accessibility of transcriptional machinery and thus regulates gene expression. In fission yeast, Schizosaccharomyces pombe, Set1 is the sole H3K4 methyltransferase and is mainly enriched at the promoters of actively transcribed genes. In contrast, Clr4 methyltransferase initiates H3K9 methylation, which has long been regarded as a hallmark of heterochromatic silencing. Lsd1 and Lsd2 are two highly conserved H3K4 and H3K9 demethylases. As these histone-modifying enzymes perform critical roles in maintaining histone methylation patterns and, consequently, gene expression profiles, cross-regulations among these enzymes are parts of the complex regulatory networks. Thus, elucidating the mechanisms that govern their signaling and mutual regulations remains crucial. Here, we demonstrated that C-terminal truncation mutants, lsd1-∆HMG and lsd2-∆C, do not compromise the integrity of the Lsd1/2 complex but impair their chromatin-binding capacity at the promoter region of target genomic loci. We identified the protein-protein interactions between Lsd1/2 and Raf2 or Swd2, which are the subunits of the Clr4 complex (CLRC) and Set1-associated complexes (COMPASS), respectively. We showed that Clr4 and Set1 modulate the protein levels of Lsd1 and Lsd2 in opposite ways through the ubiquitin-proteasome-dependent pathway. During heat stress, the protein levels of Lsd1 and Lsd2 are upregulated in a Set1-dependent manner. The increase in protein levels is crucial for differential gene expression under stressed conditions. Together, our results support a cross-regulatory model by which Set1 and Clr4 methyltransferases control the protein levels of Lsd1/2 demethylases to shape the dynamic chromatin landscape.
2023-11-16 | GSE246596 | GEO
Project description:Eukaryotic chromatin is organized into either silenced heterochromatin or relaxed euchromatin regions, which controls the accessibility of transcriptional machinery and thus regulates gene expression. In fission yeast, Schizosaccharomyces pombe, Set1 is the sole H3K4 methyltransferase and is mainly enriched at the promoters of actively transcribed genes. In contrast, Clr4 methyltransferase initiates H3K9 methylation, which has long been regarded as a hallmark of heterochromatic silencing. Lsd1 and Lsd2 are two highly conserved H3K4 and H3K9 demethylases. As these histone-modifying enzymes perform critical roles in maintaining histone methylation patterns and, consequently, gene expression profiles, cross-regulations among these enzymes are parts of the complex regulatory networks. Thus, elucidating the mechanisms that govern their signaling and mutual regulations remains crucial. Here, we demonstrated that C-terminal truncation mutants, lsd1-∆HMG and lsd2-∆C, do not compromise the integrity of the Lsd1/2 complex but impair their chromatin-binding capacity at the promoter region of target genomic loci. We identified the protein-protein interactions between Lsd1/2 and Raf2 or Swd2, which are the subunits of the Clr4 complex (CLRC) and Set1-associated complexes (COMPASS), respectively. We showed that Clr4 and Set1 modulate the protein levels of Lsd1 and Lsd2 in opposite ways through the ubiquitin-proteasome-dependent pathway. During heat stress, the protein levels of Lsd1 and Lsd2 are upregulated in a Set1-dependent manner. The increase in protein levels is crucial for differential gene expression under stressed conditions. Together, our results support a cross-regulatory model by which Set1 and Clr4 methyltransferases control the protein levels of Lsd1/2 demethylases to shape the dynamic chromatin landscape.
2023-11-16 | GSE246595 | GEO
Project description:TET proteins convert 5-methylcytosine to 5-hydroxymethylcytosine, an emerging dynamic epigenetic state of DNA that can influence transcription. Evidence has linked TET1 function to epigenetic repression complexes, yet mechanistic information, especially for the TET2 and TET3 proteins, remains limited. Here, we show a direct interaction of TET2 and TET3 with O-GlcNAc transferase (OGT). OGT does not appear to influence hmC activity, rather TET2 and TET3 promote OGT activity. TET2/3-OGT co-localize on chromatin at active promoters enriched for H3K4me3 and reduction of either TET2/3 or OGT activity results in a direct decrease in H3K4me3 and concomitant decreased transcription. Further, we show that Host Cell Factor 1 (HCF1), a component of the H3K4 methyltransferase SET1/COMPASS complex, is a specific GlcNAcylation target of TET2/3-OGT, and modification of HCF1 is important for the integrity of SET1/COMPASS. Additionally, we find both TET proteins and OGT activity promote binding of the SET1/COMPASS H3K4 methyltransferase, SETD1A, to chromatin. Finally, studies in Tet2 knockout mouse bone marrow tissue extend and support the data as decreases are observed of global GlcNAcylation and also of H3K4me3, notably at several key regulators of haematopoiesis. Together, our results unveil a step-wise model, involving TET-OGT interactions, promotion of GlcNAcylation, and influence on H3K4me3 via SET1/COMPASS, highlighting a novel means by which TETs may induce transcriptional activation.
2013-02-07 | GSE36620 | GEO