Browse
Submit Data
Databases
API
Help

Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

58 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

RAG Represents a Widespread Threat to the Lymphocyte Genome - (Mnase-seq)

ABSTRACT: 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

ORGANISM(S): Mus musculus

SUBMITTER: Yaakov Maman

PROVIDER: E-GEOD-69474 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Json Xml

Similar Datasets

RAG Represents a Widespread Threat to the Lymphocyte Genome - (ChIP-seq)

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

The In Vivo Pattern of Binding of RAG1 and RAG2 to Antigen Receptor Loci

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 IgÎº and TcrÎ± J gene segments and Igh and TcrÎ² 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-/-Î², and D708A-RAG1-/-Î² thymocytes. Histone modification H3K4me3 was analyzed in D708A-RAG1-/-Î² and wild type thymocytes.

2010-04-19 | E-GEOD-21207 | biostudies-arrayexpress

RAG Represents a Widespread Threat to the Lymphocyte Genome - (RNA-seq)

2015-08-06 | E-GEOD-69473 | biostudies-arrayexpress

RAG Represents a Widespread Threat to the Lymphocyte Genome - (ChIP-seq)

2015-08-06 | GSE69475 | GEO

RAG Represents a Widespread Threat to the Lymphocyte Genome - (Mnase-seq)

2015-08-06 | GSE69474 | GEO

RAG Represents a Widespread Threat to the Lymphocyte Genome - (RNA-seq)

2015-08-06 | GSE69473 | GEO

RAG1 targeting in the genome is dominated by chromatin interactions mediated by the non-core regions of RAG1 and RAG2

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

The In Vivo Pattern of Binding of RAG1 and RAG2 to Antigen Receptor Loci

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.

2010-04-20 | GSE21207 | GEO

Genome-wide nucleosome positioning during embryonic stem cell development [MNase-Seq]

Project description:We determined genome-wide nucleosome occupancy in mouse embryonic stem cells and their neural progenitor and embryonic fibroblast counterparts to assess features associated with nucleosome positioning during lineage commitment. Cell type and protein specific binding preferences of transcription factors to sites with either low (e.g. Myc, Klf4, Zfx) or high (e.g. Nanog, Oct4 and Sox2) nucleosome occupancy as well as complex patterns for CTCF were identified. Nucleosome depleted regions around transcription start and termination sites were broad and more pronounced for active genes, with distinct patterns for promoters classified according to their CpG-content or histone methylation marks. Throughout the genome nucleosome occupancy was dependent on the presence of certain histone methylation or acetylation modifications. In addition, the average nucleosome-repeat length increased during differentiation by 5-7 base pairs, with local variations for specific genomic regions. Our results reveal regulatory mechanisms of cell differentiation acting through nucleosome repositioning. We have determined genome-wide nucleosome position maps in mouse embryonic stem cells (ESCs), neural progenitor cells (NPCs) derived from these ESCs by retinoic acid induced differentiation as well as mouse embryonic fibroblasts (MEFs) from the corresponding mouse strain

2012-10-21 | E-GEOD-40910 | biostudies-arrayexpress

RAG Represents a Widespread Threat to the Lymphocyte Genome

Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series

2015-08-04 | E-GEOD-69478 | biostudies-arrayexpress