Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA275668 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Rag1 and Rag2 gene expression in CD4+CD8+ double positive (DP) thymocytes depends on the activity of a distant anti-silencer element (ASE) that counteracts the activity of an intergenic silencer. However, the mechanistic basis for ASE activity is unknown. Here we show that the ASE physically interacts with the distant Rag1 and Rag2 gene promoters in DP thymocytes, bringing the two promoters together to form an active chromatin hub. Moreover, we show that the ASE functions as a classical enhancer that can potently activate these promoters in the absence of the silencer or other locus elements. In thymocytes lacking the chromatin organizer SATB1, we identified a partial defect in Tcra gene rearrangement that was associated with reduced expression of Rag1 and Rag2 at the DP stage. SATB1 binds to the ASE and Rag promoters, facilitating inclusion of Rag2 in the chromatin hub and the loading of RNA polymerase II to both the Rag1 and Rag2 promoters. Our results provide a novel framework for understanding ASE function and demonstrate a novel role for SATB1 as a regulator of Rag locus organization and gene expression in DP thymocytes. Sequencing of Satb1-ChIP and input control from 6 wk old thymus
2015-02-25 | E-GEOD-66248 | biostudies-arrayexpress
Project description:Rag1 and Rag2 gene expression in CD4+CD8+ double positive (DP) thymocytes depends on the activity of a distant anti-silencer element (ASE) that counteracts the activity of an intergenic silencer. However, the mechanistic basis for ASE activity is unknown. Here we show that the ASE physically interacts with the distant Rag1 and Rag2 gene promoters in DP thymocytes, bringing the two promoters together to form an active chromatin hub. Moreover, we show that the ASE functions as a classical enhancer that can potently activate these promoters in the absence of the silencer or other locus elements. In thymocytes lacking the chromatin organizer SATB1, we identified a partial defect in Tcra gene rearrangement that was associated with reduced expression of Rag1 and Rag2 at the DP stage. SATB1 binds to the ASE and Rag promoters, facilitating inclusion of Rag2 in the chromatin hub and the loading of RNA polymerase II to both the Rag1 and Rag2 promoters. Our results provide a novel framework for understanding ASE function and demonstrate a novel role for SATB1 as a regulator of Rag locus organization and gene expression in DP thymocytes.
2015-02-25 | GSE66248 | GEO
Project description:Mammalian genomes are organized by multi-layered chromatin folding. How three-dimensional genome organization contributes to cell-type specific transcription remains unclear. We uncover genomic elements termed base-unpairing regions (BURs), distributed genome-wide, as the sole and direct targets of cell-type specific SATB1 protein in vivo. The SATB1 direct-binding profile was generated by analyzing stringently-purified genomic DNA crosslinked to its directly-bound proteins only (ureaChIP-seq). Furthermore, a SATB1-bound BUR interacts extensively and frequently over the entire 5.7 megabase gene-rich region within many regulatory regions, including those near SATB1-dependent Rag1/Rag2 genes. SATB1 depletion leads to major loss of these interactions with greatly reduced Rag1/Rag2 expression. Most BURs reside within lamina associated domains (LADs), among which SATB1 binds to cell-type specific groups of BURs. Genome organization mediated by CTCF and SATB1 are distinct as these proteins do not co-bind chromatin in vivo and their direct binding sites are mutually exclusive genome-wide. These results revealed a previously undetected chromatin organization mediated by SATB1 direct binding to selected BURs genome-wide and suggest that chromatin interactions from some of these BURs provide a regulatory network underlying cell-type specific gene expression.
2021-12-28 | GSE191146 | GEO
Project description:The RAG1/RAG2 endonuclease initiates V(D)J recombination at antigen receptor loci but also binds to thousands of places outside of these loci. RAG2 localizes directly to lysine 4 trimethylated histone 3 (H3K4me3) through a PHD finger. The relative contribution of RAG2-dependent and RAG1-intrinsic mechanisms in determining RAG1 binding patterns is not known. Through analysis of deep RAG1 ChIP-seq data, we provide a quantitative description of the forces underlying genome-wide targeting of RAG1. Surprisingly, sequence-specific DNA binding contributes minimally to RAG1 targeting outside of antigen receptor loci. Instead, RAG1 binding is driven by two distinct modes of interaction with chromatin: the first is driven by H3K4me3, promoter-focused, and dependent on the RAG2 PHD, and the second is defined by H3K27Ac, enhancer-focused, and dependent on "non-core" portions of RAG1. Based on this and additional chromatin and genomic features, we formulated a predictive model of RAG1 targeting to the genome. RAG1 binding sites predicted by our model correlate well with observed patterns of RAG1-mediated breaks in human pro-B acute lymphoblastic leukemia. Overall, this study provides an integrative model for RAG1 genome-wide binding and off-target activity, and reveals a novel role for the RAG1 non-core region in RAG1 targeting. ChIP-seq profiles of RAG1 from mouse thymocytes, and H3K27Ac from human REH cell line
2016-07-06 | E-GEOD-84052 | biostudies-arrayexpress
Project description:The RAG1/RAG2 endonuclease initiates V(D)J recombination at antigen receptor loci but also binds to thousands of places outside of these loci. RAG2 localizes directly to lysine 4 trimethylated histone 3 (H3K4me3) through a PHD finger. The relative contribution of RAG2-dependent and RAG1-intrinsic mechanisms in determining RAG1 binding patterns is not known. Through analysis of deep RAG1 ChIP-seq data, we provide a quantitative description of the forces underlying genome-wide targeting of RAG1. Surprisingly, sequence-specific DNA binding contributes minimally to RAG1 targeting outside of antigen receptor loci. Instead, RAG1 binding is driven by two distinct modes of interaction with chromatin: the first is driven by H3K4me3, promoter-focused, and dependent on the RAG2 PHD, and the second is defined by H3K27Ac, enhancer-focused, and dependent on "non-core" portions of RAG1. Based on this and additional chromatin and genomic features, we formulated a predictive model of RAG1 targeting to the genome. RAG1 binding sites predicted by our model correlate well with observed patterns of RAG1-mediated breaks in human pro-B acute lymphoblastic leukemia. Overall, this study provides an integrative model for RAG1 genome-wide binding and off-target activity, and reveals a novel role for the RAG1 non-core region in RAG1 targeting.
2016-07-06 | GSE84052 | GEO
Project description:The RAG1 endonuclease, together with its cofactor RAG2, is essential for V(D)J recombination but is a potent threat to genome stability. The sources of RAG1 mistargeting and the mechanisms that have evolved to suppress it are poorly understood. Here, we report the surprising finding that RAG1 binds to thousands of sites in the genome of developing lymphocytes, primarily at active promoters and enhancers. The genome has responded by reducing the abundance of "cryptic" recombination signals near sites of RAG1 binding. This depletion operates specifically on the RSS heptamer, with nonamers enriched at RAG1 binding sites. Reversing this RAG-driven depletion of cleavage sites by insertion of strong recombination signals creates an ectopic hub of RAG-mediated V(D)J recombination and chromosomal translocations. Our findings delineate rules governing RAG binding in the genome, identify areas at risk of RAG-mediated damage, and highlight the evolutionary struggle to accommodate programmed DNA damage in developing lymphocytes. RAG1,RAG2 and H3K4me3 ChIP-seq profiles of human thymocytes, mouse thymocytes and preB cells, and Abelson pre-B cell line treated with STI-571
2015-08-06 | E-GEOD-69475 | biostudies-arrayexpress
Project description:The RAG1 endonuclease, together with its cofactor RAG2, is essential for V(D)J recombination but is a potent threat to genome stability. The sources of RAG1 mistargeting and the mechanisms that have evolved to suppress it are poorly understood. Here, we report the surprising finding that RAG1 binds to thousands of sites in the genome of developing lymphocytes, primarily at active promoters and enhancers. The genome has responded by reducing the abundance of "cryptic" recombination signals near sites of RAG1 binding. This depletion operates specifically on the RSS heptamer, with nonamers enriched at RAG1 binding sites. Reversing this RAG-driven depletion of cleavage sites by insertion of strong recombination signals creates an ectopic hub of RAG-mediated V(D)J recombination and chromosomal translocations. Our findings delineate rules governing RAG binding in the genome, identify areas at risk of RAG-mediated damage, and highlight the evolutionary struggle to accommodate programmed DNA damage in developing lymphocytes. MNase-seq profiles of mouse thymocytes
2015-08-06 | E-GEOD-69474 | biostudies-arrayexpress
Project description:The RAG1 endonuclease, together with its cofactor RAG2, is essential for V(D)J recombination but is a potent threat to genome stability. The sources of RAG1 mistargeting and the mechanisms that have evolved to suppress it are poorly understood. Here, we report the surprising finding that RAG1 binds to thousands of sites in the genome of developing lymphocytes, primarily at active promoters and enhancers. The genome has responded by reducing the abundance of "cryptic" recombination signals near sites of RAG1 binding. This depletion operates specifically on the RSS heptamer, with nonamers enriched at RAG1 binding sites. Reversing this RAG-driven depletion of cleavage sites by insertion of strong recombination signals creates an ectopic hub of RAG-mediated V(D)J recombination and chromosomal translocations. Our findings delineate rules governing RAG binding in the genome, identify areas at risk of RAG-mediated damage, and highlight the evolutionary struggle to accommodate programmed DNA damage in developing lymphocytes. RNA-seq profiles of mouse thymocytes
2015-08-06 | E-GEOD-69473 | biostudies-arrayexpress
Project description:The critical initial step in V(D)J recombination, binding of RAG1 and RAG2 to recombination signal sequences flanking antigen receptor V, D, and J gene segments, has not previously been characterized in vivo. Here we demonstrate that RAG protein binding occurs in a highly focal manner to a small region of active chromatin encompassing Igκ and Tcrα J gene segments and Igh and Tcrβ J and J-proximal D gene segments. Formation of these small RAG-bound regions, which we refer to as recombination centers, occurs in a developmental stage- and lineage-specific manner. Each RAG protein is independently capable of specific binding within recombination centers. While RAG1 binding is restricted to regions containing recombination signal sequences, RAG2 binds extremely broadly in a pattern that mirrors that of trimethylated lysine 4 of histone 3. We propose that recombination centers coordinate V(D)J recombination by providing discrete sites within which gene segments are captured for recombination. RAG2 binding was analyzed in wild type, RAG2-/-β, and D708A-RAG1-/-β thymocytes. Histone modification H3K4me3 was analyzed in D708A-RAG1-/-β and wild type thymocytes.
2010-04-19 | E-GEOD-21207 | biostudies-arrayexpress
Project description:Special AT-rich binding protein 1 (SATB1) is a global chromatin organizer and a transcription factor induced by interleukin-4 (IL-4) during the early T helper 2 (Th2) cell differentiation. In this study, we investigated the role of SATB1 in T helper cell differentiation by performing ChIP-on-chip analysis of human cord blood CD4+ T cells cultured in Th1 and Th2 conditions. These results were combined with gene expression profiling results from human differentiating Th cells in which expression of SATB1 was downregulated by RNA interference (RNAi).Our results indicate that SATB1 regulates and is bound to sixty genes in primary human CD4+ T cells, including several IL-12 and/or IL-4 regulated factors, suggesting a role in the development or function of Th subtypes. Cross-linked chromatin obtained from human CD4+ T cells isolated from cord blood cultured in Th1 and Th2 conditions for 24 h was immunoprecipitated with anti-SATB1 antibody.
2010-05-16 | E-GEOD-17380 | biostudies-arrayexpress