Mus musculus
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA179147 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Mutations in mouse and human Nfe2, Fli1 and Runx1 cause thrombocytopenia. We applied genome- wide chromatin dynamics and ChIP-seq to determine these transcription factors’ (TFs) activities in terminal megakaryocyte (MK) maturation. Enhancers with H3K4me2-marked nucleosome pairs were most enriched for NF-E2, FLI and RUNX sequence motifs, suggesting that this TF triad controls much of the late MK program. ChIP-seq revealed NF-E2 occupancy near previously implicated target genes, whose expression is compromised in Nfe2-null cells, and many other genes that become active late in MK differentiation. FLI and RUNX were also the motifs most enriched near NF-E2 binding sites and ChIP-seq implicated FLI1 and RUNX1 in activation of late MK, including NF-E2-dependent, genes. Histones showed limited activation in regions of single TF binding, while enhancers that bind NF-E2 and either RUNX1, FLI1 or both TFs gave the highest signals for TF occupancy and H3K4me2; these enhancers associated best with genes activated late in MK maturation. Thus, three essential TFs co- occupy late-acting cis-elements and show evidence for additive activity at genes responsible for platelet assembly and release. These findings provide a rich dataset of TF and chromatin dynamics in primary MK and explain why individual TF losses cause thrombopocytopenia.
2016-07-11 | GSE42108 | GEO
Project description:Hematopoiesis is a well-established model system to study molecular mechanisms of lineage-specific differentiation. Key transcription factors (TFs), such as PU.1, NF-E2 and GATA1 are implicated in crucial aspects of distinct hematopoietic lineages. How TFs collaborate with histone modificatons and how they affect the chromatin status remains to be elucidated. Chromatin-Immunoprecipitation followed by next-generation sequencing (ChIP-seq) has been proven to be an excellent tool to study chromatin modifications genome-wide. In this study, ChIP-seq was used to investigate the H3K4me2 landscape at enhancers during hematopoietic differentiation, starting from the hematopoietic stem cell (HSC) up to the fully differentiated erythrocyte, megakaryocyte or granulocyte. Although cell morphology and gene expression profiles differ extensively in committed erythrocytes, megakaryocytes and granulocytes, the genomic landscape of H3K4me2 is surprisingly alike across the three cell types. Granulocytes, in particular, seem to display an ‘erythocyte-like’ chromatin pattern. Similar results were observed for another chromatin mark, H3K27ac. Unexpectedly, the common progenitors of erythrocytes and granulocytes do not display a similar chromatin pattern, excluding the idea that the H3K4me2 mark is placed early on during differentiation. These results also suggest that the chromatin state is probably not the determining factor for lineage differentiation, but that rather lineage specific TF binding is important. In agreement with this, mature megakaryocytes loose the H3K4me2 mark surrounding erythrocyte-specific genes. This might be explained because megakaryocytes and erythrocytes both express the lineage specific TFs GATA1 and NF-E2. Altogether, we show that committed granulocytes and erythrocytes display similar H3K4me2 and H3K27ac patterns, and that those marks alone cannot predict which genes will be expressed eventually. Genomic ChIP-Seq on key transcription factors and histone modification marks in hematopoiesis
2014-07-28 | E-GEOD-42110 | biostudies-arrayexpress
Project description:Hematopoiesis is a well-established model system to study molecular mechanisms of lineage-specific differentiation. Key transcription factors (TFs), such as PU.1, NF-E2 and GATA1 are implicated in crucial aspects of distinct hematopoietic lineages. How TFs collaborate with histone modificatons and how they affect the chromatin status remains to be elucidated. Chromatin-Immunoprecipitation followed by next-generation sequencing (ChIP-seq) has been proven to be an excellent tool to study chromatin modifications genome-wide. In this study, ChIP-seq was used to investigate the H3K4me2 landscape at enhancers during hematopoietic differentiation, starting from the hematopoietic stem cell (HSC) up to the fully differentiated erythrocyte, megakaryocyte or granulocyte. Although cell morphology and gene expression profiles differ extensively in committed erythrocytes, megakaryocytes and granulocytes, the genomic landscape of H3K4me2 is surprisingly alike across the three cell types. Granulocytes, in particular, seem to display an ‘erythocyte-like’ chromatin pattern. Similar results were observed for another chromatin mark, H3K27ac. Unexpectedly, the common progenitors of erythrocytes and granulocytes do not display a similar chromatin pattern, excluding the idea that the H3K4me2 mark is placed early on during differentiation. These results also suggest that the chromatin state is probably not the determining factor for lineage differentiation, but that rather lineage specific TF binding is important. In agreement with this, mature megakaryocytes loose the H3K4me2 mark surrounding erythrocyte-specific genes. This might be explained because megakaryocytes and erythrocytes both express the lineage specific TFs GATA1 and NF-E2. Altogether, we show that committed granulocytes and erythrocytes display similar H3K4me2 and H3K27ac patterns, and that those marks alone cannot predict which genes will be expressed eventually.
2014-07-28 | GSE42110 | GEO
Project description:RUNX1 transcription factor (TF) is a key regulator of megakaryocytic development and when mutated is associated with familial platelet disorder and predisposition to acute myeloid leukemia (FPD-AML). We used mice lacking Runx1 specifically in megakaryocytes (MKs) to characterize the Runx1-mediated transcriptional program during advanced stages of MK differentiation. Gene expression and chromatin-immunoprecipitation-sequencing (ChIP-seq) of Runx1 and p300 identified functional Runx1-bound MK enhancers. Runx1/p300 co-bound regions showed significant enrichment in genes important for MK and platelet homeostasis. Runx1-bound regions were highly enriched in RUNX and ETS motifs and to a lesser extent in GATA motif. The data provides the first example of genome-wide Runx1/p300 occupancy in maturating FL-MK, unravels the Runx1-regulated program controlling MK maturation in vivo and identifies its bona fide regulated genes. It advances our understanding of the molecular events that upon mutations in RUNX1 lead to the predisposition to familial platelet disorders and FPD-AML. Gene expression profiles of mature megakaryocytes taken from fetal livers of megakaryocyte-specific Runx1 knockout mice, using Runx1F/F/Pf4-Cre mice versus control (WT) mice.
2013-03-22 | E-GEOD-45373 | biostudies-arrayexpress
Project description:We have mapped the binding sites for the five key regulators GATA1, GATA2, RUNX1, FLI1 and TAL1/SCL in primary human megakaryocytes. Statistical analysis identified subsets of enriched as well as depleted combinatorial binding patterns. In particular simultaneous binding by all 5 factors was highly enriched and occurred in the vicinity of many genes known to be involved in blood and megakaryocyte development. Knock down in zebrafish of 8 of these genes with no previously known role in hematopoiesis, revealed all to be essential for thrombocyte and/or erythroid development. Combinatorial analysis of multi-factor ChIP-Seq datasets coupled with a high-throughput in vivo screen therefore offers a powerful strategy to identify novel essential regulators of complex mammalian differentiation processes. 5 transcription factors and rabbit-IgG in megakaryocytes.
2011-06-01 | E-GEOD-24674 | biostudies-arrayexpress
Project description:The Stem Cell Leukemia (Scl or Tal1) protein forms part of a multimeric transcription factor complex required for normal megakaryopoiesis. However, unlike other members of this complex such as Gata1, Fli1 and Runx1, mutations of Scl have not been observed as a cause of inherited thrombocytopenia. We postulated that functional redundancy with its closely related family member, Lymphoblastic Leukemia 1 (Lyl1) might explain this observation. To determine if Lyl1 can substitute for Scl in megakaryopoiesis, we examined the platelet phenotype of mice lacking one or both factors in megakaryocytes. Conditional Scl knockout mice crossed with transgenic mice expressing Cre recombinase under the control of the mouse platelet factor 4 (Pf4) promoter generated megakaryocytes with markedly reduced but not absent Scl. These Pf4SclcKO mice had mild thrombocytopenia and subtle defects in platelet aggregation. However, Pf4SclcKO mice generated on a Lyl1-null background (double knockout, DKO mice) had severe macrothrombocytopenia, abnormal megakaryocyte morphology, defective pro-platelet formation and markedly impaired platelet aggregation. DKO megakaryocytes, but not single knockouts, had reduced expression of Gata1, Fli1, Nfe2 and many other genes that cause inherited thrombocytopenia. These gene expression changes were significantly associated with shared Scl and Lyl1 E-box binding sites that were also enriched for Gata1, Ets and Runx1 motifs. Thus, Scl and Lyl1 share functional roles in platelet production and function by regulating expression of partner proteins including Gata1 and Fli1. We propose that this functional redundancy provides one explanation for the absence of Scl and Lyl1 mutations as a cause of inherited thrombocytopenia.
2020-12-21 | GSE125025 | GEO
Project description:Genome-wide localization of NF-E2 p45 in mouse primary megakaryocytes.
| PRJNA179441 | ENA
Project description:Inherited thrombocytopenia results in low platelet counts and increased bleeding. Subsets of these patients have monoallelic germline mutations in ETV6 or RUNX1 and a heightened risk of developing hematologic malignancies. Utilizing CRISPR/Cas9, we compared the in vitro phenotype of hematopoietic progenitor cells and megakaryocytes derived from induced pluripotent stem cell (iPSC) lines harboring mutations in either ETV6 or RUNX1. Both mutant lines display phenotypes consistent with a platelet-bleeding disorder. Surprisingly, these cellular phenotypes were largely distinct. The ETV6-mutant iPSCs yield more hematopoietic progenitor cells and megakaryocytes, but the megakaryocytes are immature and less responsive to agonist stimulation. On the contrary, RUNX1-mutant iPSCs yield fewer hematopoietic progenitor cells and megakaryocytes, but the megakaryocytes are more responsive to agonist stimulation. However, both mutant iPSC lines display defects in proplatelet formation. Our work highlights that while patients harboring germline ETV6 or RUNX1 mutations have similar clinical phenotypes, the molecular mechanisms may be distinct.
2021-03-06 | GSE168326 | GEO
Project description:Combinatorial actions of relatively few transcription factors control hematopoietic differentiation. To investigate this process in erythro-megakaryopoiesis, we correlated the genome-wide chromatin occupancy signatures of four master hematopoietic transcription factors (GATA1, GATA2, SCL/TAL1 and FLI1) and three diagnostic histone modification marks with the gene expression changes that occur during development of primary megakaryocytes (MEG) and erythroblasts (ERY) from murine fetal liver hematopoietic stem/progenitor cells. We identified a robust, genome-wide mechanism of MEG-specific lineage priming by a previously described stem/progenitor cell-expressed transcription factor heptad (GATA2, LYL1, SCL/TAL1, FLI1, ERG, RUNX1, LMO2) binding to MEG-specific cis-regulatory modules in multipotential hematopoietic progenitors. This is followed by genome-wide GATA factor switching that mediates further induction of MEG-specific genes following lineage commitment. Interaction between GATA and ETS factors appears to be a key determinant of these processes. In contrast, ERY-specific lineage priming occurs is biased toward GATA2-independent mechanisms. In addition to its role in MEG lineage priming, GATA2 plays an extensive role in late megakaryopoiesis as a transcriptional repressor at loci defined by a specific DNA signature. Our findings reveal important new insights into how ERY and MEG lineages arise from a common bipotential precursor via overlapping and divergent functions of shared hematopoietic transcription factors. Gene expression changes during the development of primary megakaryocytes (MEG) and erythroblasts (ERY) from murine fetal liver hematopoietic stem/progenitor cells
2013-08-09 | E-GEOD-49664 | biostudies-arrayexpress
Project description:Genome-wide analysis of GATA1, GATA2, RUNX1, FLI1 and SCL binding in primary human megakaryocytes
| PRJNA132361 | ENA