LEM-2 ChIP-seq to study chromatin anchoring
Ontology highlight
ABSTRACT:
ORGANISM(S): Caenorhabditis elegans
PROVIDER: GSE74133 | GEO | 2015/12/11
SECONDARY ACCESSION(S): PRJNA299148
REPOSITORIES: GEO
Similar Datasets
Project description:Chromatin Immunoprecipitation against the nuclear envelope protein LEM-2 to detect association to the nuclear periphery. LEM-2 ChIP was performed on early embryo fixed extracts for wild-type and two mutants that have altered position of a perinuclear chromatin reporter. LEM-2 ChIP on early embryo chromatin extracts of three different genotypes: wild-type, met-2 set-25_delta_delta and cec-4_delta, in two independent biological replicas
2015-12-11 | E-GEOD-74133 | biostudies-arrayexpress
Project description:RNA-seq for monitoring expression levels in mutants that do not anchor chromatin at the nuclear periphery. RNA-seq of depleted rRNA samples of early embryo extracts for three different genotypes: wild-type, cec-4_delta and met-2 set-25_delta_delta, in two independent biological replicas
2015-12-11 | E-GEOD-74067 | biostudies-arrayexpress
Project description:In eukaryotic cells, local chromatin structure and chromatin organization in the nucleus both influence transcriptional regulation. At the local level, the Fun30 chromatin remodeler Fft3 is essential for maintaining proper chromatin structure at centromeres and subtelomeres in fission yeast. Using genome-wide mapping and live cell imaging, we show that this role is linked to controlling nuclear organization of its targets. In fft3M-NM-^T cells, subtelomeres lose their association with the LEM domain protein Man1 at the nuclear periphery and move to the interior of the nucleus. Furthermore, genes in these domains are upregulated and active chromatin marks increase. Fft3 is also enriched at retrotransposon-derived long terminal repeat (LTR) elements at the borders of subtelomeres and at tRNA genes. In cells lacking Fft3, these sites lose their peripheral positioning and show reduced nucleosome occupancy. We propose that Fft3 has a global role in mediating association between specific chromatin domains and components of the nuclear envelope by maintaining chromatin structure required for anchoring DNA insulators to nuclear pores. For MNase samples, duplicate mutant mononucleosome fractions were compared with duplicate WT mononucleosomes.
2015-03-02 | E-GEOD-58012 | biostudies-arrayexpress
Project description:In eukaryotic cells, local chromatin structure and chromatin organization in the nucleus both influence transcriptional regulation. At the local level, the Fun30 chromatin remodeler Fft3 is essential for maintaining proper chromatin structure at centromeres and subtelomeres in fission yeast. Using genome-wide mapping and live cell imaging, we show that this role is linked to controlling nuclear organization of its targets. In fft3Δ cells, subtelomeres lose their association with the LEM domain protein Man1 at the nuclear periphery and move to the interior of the nucleus. Furthermore, genes in these domains are upregulated and active chromatin marks increase. Fft3 is also enriched at retrotransposon-derived long terminal repeat (LTR) elements at the borders of subtelomeres and at tRNA genes. In cells lacking Fft3, these sites lose their peripheral positioning and show reduced nucleosome occupancy. We propose that Fft3 has a global role in mediating association between specific chromatin domains and components of the nuclear envelope by maintaining chromatin structure required for anchoring DNA insulators to nuclear pores.
2015-03-02 | GSE47464 | GEO
Project description:In eukaryotic cells, local chromatin structure and chromatin organization in the nucleus both influence transcriptional regulation. At the local level, the Fun30 chromatin remodeler Fft3 is essential for maintaining proper chromatin structure at centromeres and subtelomeres in fission yeast. Using genome-wide mapping and live cell imaging, we show that this role is linked to controlling nuclear organization of its targets. In fft3Δ cells, subtelomeres lose their association with the LEM domain protein Man1 at the nuclear periphery and move to the interior of the nucleus. Furthermore, genes in these domains are upregulated and active chromatin marks increase. Fft3 is also enriched at retrotransposon-derived long terminal repeat (LTR) elements at the borders of subtelomeres and at tRNA genes. In cells lacking Fft3, these sites lose their peripheral positioning and show reduced nucleosome occupancy. We propose that Fft3 has a global role in mediating association between specific chromatin domains and components of the nuclear envelope by maintaining chromatin structure required for anchoring DNA insulators to nuclear pores.
2015-03-02 | GSE58012 | GEO
Project description:Laminopathies are caused by mutations in components of the nuclear envelope (NE). While most NE components are widely expressed, laminopathies affect only a subset of tissues. However, the understanding of the molecular mechanisms that explain this phenomenon is still elusive. Here we have performed a genome wide DamID analysis in adult C. elegans nematodes comparing the DNA association profile of two components of the NE, Lamin/LMN-1 and Emerin/EMR-1. Although both proteins were associated to silent DNA, EMR-1 showed a predominant role in the anchoring of muscle and neuronal promoters to the nuclear periphery. Deletion of either EMR-1 or LEM-2, another integral NE protein, caused local changes in nuclear architecture with both increased and decreased LMN-1 association. Comparison of Dam::LMN-1 and Dam::EMR-1 DNA assotiation in wild type strains and Dam::LMN-1 DNA association in wild type, lem-2(tm1582) and emr-1(gk119) mutant backgrounds.
2013-12-02 | E-GEOD-44188 | biostudies-arrayexpress
Project description:RNA-seq for monitoring expression levels in mutants that do not anchor chromatin at the nuclear periphery.
2015-12-11 | GSE74067 | GEO
Project description:In eukaryotic cells, local chromatin structure and chromatin organization in the nucleus both influence transcriptional regulation. At the local level, the Fun30 chromatin remodeler Fft3 is essential for maintaining proper chromatin structure at centromeres and subtelomeres in fission yeast. Using genome-wide mapping and live cell imaging, we show that this role is linked to controlling nuclear organization of its targets. In fft3M-NM-^T cells, subtelomeres lose their association with the LEM domain protein Man1 at the nuclear periphery and move to the interior of the nucleus. Furthermore, genes in these domains are upregulated and active chromatin marks increase. Fft3 is also enriched at retrotransposon-derived long terminal repeat (LTR) elements at the borders of subtelomeres and at tRNA genes. In cells lacking Fft3, these sites lose their peripheral positioning and show reduced nucleosome occupancy. We propose that Fft3 has a global role in mediating association between specific chromatin domains and components of the nuclear envelope by maintaining chromatin structure required for anchoring DNA insulators to nuclear pores. For DamID samples, we recorded methylation levels for Dam fusion proteins and compared them to Dam-only control samples. For ChIP samples, we compared immuno-precipitated DNA to mock or input controls.
2015-03-02 | E-GEOD-47464 | biostudies-arrayexpress
Project description:Genomic regions preferentially associate with regions of similar transcriptional activity, partitioning genomes into active and inactive compartments within the nucleus. Here we explored mechanisms controlling genome compartment organization in C. elegans and investigated roles for compartments in regulating gene expression. The distal arms of C. elegans chromosomes, which are enriched for heterochromatic histone modifications including H3K9me, interact with each other both in cis and in trans, while interacting less frequently with central regions of chromosomes, leading to genome compartmentalization. Arms are anchored to the nuclear periphery via the nuclear envelope protein CEC-4, which binds to H3K9me. By performing genome-wide chromosome conformation capture experiments (Hi-C), we showed that eliminating H3K9me1/me2/me3 through mutations in the methyltransferase genes met-2 and set-25 significantly impaired formation of genome compartments. cec-4 mutations also impaired compartmentalization, but to a lesser extent. We found that H3K9me promotes compartmentalization through two distinct mechanisms: perinuclear anchoring of chromosome arms via CEC-4 to promote their cis association, and an anchoring-independent mechanism that compacts individual chromosome arms. In both met-2 set-25 and cec-4 mutants, no dramatic changes in gene expression were found for genes that switched compartments or for genes that remained in their original compartment, suggesting that compartment strength does not dictate gene expression levels. Furthermore, H3K9me, but not perinuclear anchoring, also contributes to formation of another prominent feature of chromosome organization, megabase-scale topologically associating domains on X that are established by the dosage-compensation condensin complex. Our results demonstrate that H3K9me plays crucial roles in regulating genome organization at multiple levels.
2020-04-21 | GSE144251 | GEO
Project description:Genomic regions preferentially associate with regions of similar transcriptional activity, partitioning genomes into active and inactive compartments within the nucleus. Here we explored mechanisms controlling genome compartment organization in C. elegans and investigated roles for compartments in regulating gene expression. The distal arms of C. elegans chromosomes, which are enriched for heterochromatic histone modifications including H3K9me, interact with each other both in cis and in trans, while interacting less frequently with central regions of chromosomes, leading to genome compartmentalization. Arms are anchored to the nuclear periphery via the nuclear envelope protein CEC-4, which binds to H3K9me. By performing genome-wide chromosome conformation capture experiments (Hi-C), we showed that eliminating H3K9me1/me2/me3 through mutations in the methyltransferase genes met-2 and set-25 significantly impaired formation of genome compartments. cec-4 mutations also impaired compartmentalization, but to a lesser extent. We found that H3K9me promotes compartmentalization through two distinct mechanisms: perinuclear anchoring of chromosome arms via CEC-4 to promote their cis association, and an anchoring-independent mechanism that compacts individual chromosome arms. In both met-2 set-25 and cec-4 mutants, no dramatic changes in gene expression were found for genes that switched compartments or for genes that remained in their original compartment, suggesting that compartment strength does not dictate gene expression levels. Furthermore, H3K9me, but not perinuclear anchoring, also contributes to formation of another prominent feature of chromosome organization, megabase-scale topologically associating domains on X that are established by the dosage-compensation condensin complex. Our results demonstrate that H3K9me plays crucial roles in regulating genome organization at multiple levels.
2020-04-21 | GSE144252 | GEO