Similar Datasets
Project description:Germline heterozygous mutations in GATA2 are associated with a syndrome characterized by cytopenias, atypical infections, and increased risk of hematologic malignancies. Due to embryonic lethality of Gata2-/- mice, the role of germline loss of GATA2 has not been studied in adult hematopoiesis. Here, we generated a zebrafish mutant of gata2b, which in adulthood recapitulated the myelomonocytopenia and B cell lymphopenia of GATA2 syndrome. Using single cell epigenetic and transcriptomic analyses, we showed that loss of gata2b alters chromosome accessibility and results in gene expression changes in both early myeloid and lymphoid progenitors. We found differentiation block with skewing away from the monocytic program in myeloid progenitors in gata2bko zebrafish. In lymphoid progenitors, gata2b loss led to increased lymphoid priming but with incomplete B cell lymphopoiesis. These results place GATA2 in critical junctions of lineage specification in adult hematopoiesis.
2021-02-25 | GSE151230 | GEO
Project description:Germline heterozygous mutations in GATA2 are associated with a syndrome characterized by cytopenias, atypical infections, and increased risk of hematologic malignancies. Due to embryonic lethality of Gata2-/- mice, the role of germline loss of GATA2 has not been studied in adult hematopoiesis. Here, we generated a zebrafish mutant of gata2b, which in adulthood recapitulated the myelomonocytopenia and B cell lymphopenia of GATA2 syndrome. Using single cell epigenetic and transcriptomic analyses, we showed that loss of gata2b alters chromosome accessibility and results in gene expression changes in both early myeloid and lymphoid progenitors. We found differentiation block with skewing away from the monocytic program in myeloid progenitors in gata2bko zebrafish. In lymphoid progenitors, gata2b loss led to increased lymphoid priming but with incomplete B cell lymphopoiesis. These results place GATA2 in critical junctions of lineage specification in adult hematopoiesis.
2021-02-25 | GSE151231 | GEO
Project description:Gata2 loss alters epigenetic priming and gene expression profiles in early myeloid and lymphoid progenitors leading to cytopenias
| PRJNA635158 | ENA
Project description:Gata2 loss alters epigenetic priming and gene expression profiles in early myeloid and lymphoid progenitors leading to cytopenias [ATAC-seq]
| PRJNA635160 | ENA
Project description:Gata2 loss alters epigenetic priming and gene expression profiles in early myeloid and lymphoid progenitors leading to cytopenias [RNA-seq]
| PRJNA635161 | ENA
Project description:Germline heterozygous mutations in GATA2 are associated with a syndrome characterized by cytopenias, atypical infections, and increased risk of hematologic malignancies. Here, we generated a zebrafish mutant of gata2b that recapitulated the myelomonocytopenia and B-cell lymphopenia of GATA2 deficiency syndrome. Using single-cell assay for transposase accessible chromatin with sequencing of marrow cells, we showed that loss of gata2b led to contrasting alterations in chromosome accessibility in early myeloid and lymphoid progenitors, associated with defects in gene expression. Within the myeloid lineage in gata2b mutant zebrafish, we identified an attenuated myeloid differentiation with reduced transcriptional priming and skewing away from the monocytic program. In contrast, in early lymphoid progenitors, gata2b loss led to accumulation of B-lymphoid transcription factor accessibility coupled with increased expression of the B-cell lineage-specification program. However, gata2b mutant zebrafish had incomplete B-cell lymphopoiesis with loss of lineage-specific transcription factor accessibility in differentiating B cells, in the context of aberrantly reduced oxidative metabolic pathways. Our results establish that transcriptional events in early progenitors driven by Gata2 are required to complete normal differentiation.
| S-EPMC8221101 | biostudies-literature
Project description:Loss-of-function mutations of cyclic-AMP response element binding protein, binding protein (CREBBP) are prevalent in lymphoid malignancies. However, the tumour suppressor functions of CREBBP remain unclear. We demonstrate that loss of Crebbp in murine haematopoietic stem and progenitor cells (HSPCs) leads to increased development of B-cell lymphomas. This is preceded by accumulation of hyperproliferative lymphoid progenitors with a defective DNA damage response (DDR) due to a failure to acetylate p53. We identify a premalignant lymphoma stem cell population with decreased H3K27ac, which undergoes transcriptional and genetic evolution due to the altered DDR, resulting in lymphomagenesis. Importantly, when Crebbp is lost later in lymphopoiesis, cellular abnormalities are lost and tumour generation is attenuated. We also document that CREBBP mutations may occur in HSPCs from patients with CREBBP-mutated lymphoma. These data suggest that earlier loss of Crebbp is advantageous for lymphoid transformation and inform the cellular origins and subsequent evolution of lymphoid malignancies.
| S-EPMC5633079 | biostudies-literature
Project description:The mechanism of lineage commitment from hematopoietic stem cells (HSCs) is not well understood. Although commitment to either the lymphoid or the myeloid lineage is popularly viewed as the first step of lineage restriction from HSCs, this model of hematopoietic differentiation has recently been challenged. The previous identification of multipotent progenitors (MPPs) that can produce lymphocytes and granulocyte/macrophages (GMs) but lacks erythroid differentiation ability suggests the existence of an alternative HSC differentiation program. Contribution to different hematopoietic lineages by these MPPs under physiological conditions, however, has not been carefully examined. In this study, we performed a refined characterization of MPPs by subfractionating three distinct subsets based on Flt3 and vascular cell adhesion molecule 1 expression. These MPP subsets differ in their ability to give rise to erythroid and GM lineage cells but are equally potent in lymphoid lineage differentiation in vivo. The developmental hierarchy of these MPP subsets demonstrates the sequential loss of erythroid and then GM differentiation potential during early hematopoiesis. Our results suggest that the first step of lineage commitment from HSCs is not simply a selection between the lymphoid and the myeloid lineage.
| S-EPMC2118384 | biostudies-other
Project description:Early innate lymphoid progenitors (EILPs) have recently been identified in mouse adult bone marrow as a multipotential progenitor population specified toward innate lymphoid cell (ILC) lineages, but their relationship with other described ILC progenitors is still unclear. In this study, we examine the progenitor-successor relationships between EILPs, all-lymphoid progenitors (ALPs), and ILC precursors (ILCps). Functional, bioinformatic, phenotypical, and genetic approaches collectively establish EILPs as an intermediate progenitor between ALPs and ILCps. Our work additionally provides new candidate regulators of ILC development and clearly defines the stage of requirement of transcription factors key for early ILC development.
| S-EPMC5748853 | biostudies-literature
Project description:The capacity of the hematopoietic system to promptly respond to peripheral demands relies on adequate pools of progenitors able to transiently proliferate and differentiate in a regulated manner. However, little is known about factors that may restrain progenitor maturation to maintain their reservoirs. Conditional knockout mice for the Pbx1 proto-oncogene have a significant reduction in lineage-restricted progenitors in addition to a profound defect in hematopoietic stem cell (HSC) self-renewal. Through analysis of purified progenitor proliferation, differentiation capacity and transcriptional profiling, we demonstrate that Pbx1 regulates the lineage-specific output of multipotent and oligopotent progenitors. In the absence of Pbx1 multipotent progenitor (MPP) and common myeloid progenitor (CMP) pools are reduced due to aberrantly rapid myeloid maturation. This is associated with premature expression of myeloid differentiation genes and decreased maintenance of proto-oncogene transcriptional pathways, including reduced expression of Meis1, a Pbx1 dimerization partner, and its subordinate transcriptional program. Conversely, Pbx1 maintains the lymphoid differentiation potential of lymphoid-primed MPPs (LMPPs) and common lymphoid progenitors (CLPs), whose reduction in the absence of Pbx1 is associated with a defect in lymphoid priming that is also present in CMPs, which persistently express lymphoid and HSC genes underlying a previously unappreciated lineage promiscuity that is maintained by Pbx1. These results demonstrate a role for Pbx1 in restraining myeloid maturation while maintaining lymphoid potential to appropriately regulate progenitor reservoirs.
| S-EPMC3711206 | biostudies-literature