Project description:This SuperSeries is composed of the following subset Series: GSE25079: Epistasis analysis of Runx1 and Gata1 over HoxA3 in hemogenic endothelium GSE25080: Genes regulated by HoxA3 in endothelial and hematopoietic progenitors Refer to individual Series
Project description:Human embryonic stem cells (hESCs) are a powerful tool for modeling regenerative therapy. To search for the genes that promote hematopoietic development from human pluripotent stem cell, we overexpressed a list of hematopoietic regulator genes in human pluripotent stem cell-derived CD34+CD43- endothelial cells (ECs) enriched in hemogenic endothelium. Among genes tested, only SOX17, a gene encoding a transcription factor of the SOX family, promoted cell growth and supported expansion of CD34+CD43+CD45-/low cells expressing a hemogenic endothelial maker VE-cadherin. SOX17 was highly expressed in CD34+CD43- ECs but at a low level in CD34+CD43+CD45- pre-hematopoietic progenitor cells (pre-HPCs) and CD34+CD43+CD45+ HPCs. SOX17-overexpressing cells formed sphere-like colonies and generated few hematopoietic progenies. However, they retained hemogenic potential and gave rise to hematopoietic progenies upon inactivation of SOX17. Global gene expression analyses revealed that the CD34+CD43+CD45-/low cells expanded upon overexpression of SOX17 are hemogenic endothelium-like cells developmentally placed between ECs and pre-HPCs. Of interest, SOX17 also reprogrammed both pre-HPCs and HPCs into hemogenic endothelium-like cells. Genome-wide mapping of SOX17 revealed that SOX17 directly activates transcription of key regulator genes for vasculogenesis, hematopoiesis, and erythrocyte differentiation. Depletion of SOX17 in CD34+CD43- ECs severely compromised their hemogenic activity. These findings suggest that SOX17 plays a critical role in priming hemogenic potential in ECs, thereby regulates hematopoietic development from hESCs. This SuperSeries is composed of the SubSeries listed below.
Project description:Human embryonic stem cells (hESCs) are a powerful tool for modeling regenerative therapy. To search for the genes that promote hematopoietic development from human pluripotent stem cell, we overexpressed a list of hematopoietic regulator genes in human pluripotent stem cell-derived CD34+CD43- endothelial cells (ECs) enriched in hemogenic endothelium. Among genes tested, only SOX17, a gene encoding a transcription factor of the SOX family, promoted cell growth and supported expansion of CD34+CD43+CD45-/low cells expressing a hemogenic endothelial maker VE-cadherin. SOX17 was highly expressed in CD34+CD43- ECs but at a low level in CD34+CD43+CD45- pre-hematopoietic progenitor cells (pre-HPCs) and CD34+CD43+CD45+ HPCs. SOX17-overexpressing cells formed sphere-like colonies and generated few hematopoietic progenies. However, they retained hemogenic potential and gave rise to hematopoietic progenies upon inactivation of SOX17. Global gene expression analyses revealed that the CD34+CD43+CD45-/low cells expanded upon overexpression of SOX17 are hemogenic endothelium-like cells developmentally placed between ECs and pre-HPCs. Of interest, SOX17 also reprogrammed both pre-HPCs and HPCs into hemogenic endothelium-like cells. Genome-wide mapping of SOX17 revealed that SOX17 directly activates transcription of key regulator genes for vasculogenesis, hematopoiesis, and erythrocyte differentiation. Depletion of SOX17 in CD34+CD43- ECs severely compromised their hemogenic activity. These findings suggest that SOX17 plays a critical role in priming hemogenic potential in ECs, thereby regulates hematopoietic development from hESCs. This SuperSeries is composed of the SubSeries listed below. ChIP on chip analysis was carried out using the Mouse Promoter ChIP-on-chip Microarray Set (G4490A, Agilent, Palo Alto, Calif., USA). MEFs were subjected to ChIP assay using a Ring1B antibody. Purified immunoprecipitated and input DNA was subjected to T7 RNA polymerase-based amplification. Labeling, hybridization and washing were carried out according to the Agilent mammalian ChIP-on-chip protocol (ver.9.0). Scanned images were quantified with Agilent Feature Extraction software under standard conditions. Human ES cells were differentiated for 6 days in EBs, then CD34+CD43-CD45- endothelial cells were isolated, plated onto OP9 cells, and transduced with the 4OH-tamoxifen (4OHT)-inducible 3M-CM-^WFLAG-tagged Sox17-ERT retrovirus. The cells were seeded on OP9 stromal cells and cultured in the presence of 4OH-tamoxifen. At day 27 of the co-culture with OP9 cells, CD34+CD43+CD45low hemogenic endothelium-like cells overexpressing Sox17-ERT were collected by CD34 magnetic-activated cell sorting (MACS) and subjected to a ChIP-chip analysis. ChIP on chip analysis was carried out using the Mouse Promoter ChIP-on-chip Microarray Set (G4490A, Agilent, Palo Alto, Calif., USA). MEFs were subjected to ChIP assay using a Ring1B antibody. Purified immunoprecipitated and input DNA was subjected to T7 RNA polymerase-based amplification. Labeling, hybridization and washing were carried out according to the Agilent mammalian ChIP-on-chip protocol (ver.9.0). Scanned images were quantified with Agilent Feature Extraction software under standard conditions. Human ES cells were differentiated for 6 days in EBs, then CD34+CD43-CD45- endothelial cells were isolated, plated onto OP9 cells, and transduced with the 4OH-tamoxifen (4OHT)-inducible 3M-CM-^WFLAG-tagged Sox17-ERT retrovirus. The cells were seeded on OP9 stromal cells and cultured in the presence of 4OH-tamoxifen. At day 27 of the co-culture with OP9 cells, CD34+CD43+CD45low hemogenic endothelium-like cells overexpressing Sox17-ERT were collected by CD34 magnetic-activated cell sorting (MACS) and subjected to a ChIP-chip analysis.
Project description:Hemogenic endothelium (HE) is the source of HSCs in the developing embryo. In this study we have identified the hemogenic endothelial progenitors and their precursors originating from differentiated H1 cells on OP9 stromal cells. RNA-seq of hemogenic endothelial progenitors and their precursors originating from differentiated H1 cells on OP9 stromal cells.
Project description:Cell fate decisions during hematopoiesis are governed by lineage-specific transcription factors, such as RUNX1, SCL/TAL1, FLI1 and C/EBP family members. In order to gain insight about how these transcription factors regulate the activation of hematopoietic genes during embryonic development, we measured the genome-wide dynamics of transcription factor assembly on their target genes during the RUNX1-dependent transition from hemogenic endothelium to hematopoietic progenitors. Using a RUNX1-/- embryonic stem cell differentiation model expressing an inducible RUNX1 gene, we show that in the absence of RUNX1, SCL/TAL1, FLI1 and C/EBPM-NM-2 prime hematopoietic genes and that this early priming is required for correct temporal expression of the myeloid master regulator PU.1 and its downstream targets. After induction, RUNX1 binds to numerous new sites, initiating a local increase of histone acetylation and rapid global alterations in the binding patterns of SCL/TAL1 and FLI1. The acquisition of hematopoietic fate controlled by RUNX1 therefore does not represent the establishment of a new regulatory layer on top of a pre-existing hemogenic endothelium program but instead entails global reorganization of lineage-specific transcription factor assemblies. ChIPseq data from transcription factors Runx1, Fli-1, Scl/Tal1 and C/EBPM-NM-2, histone modification H3K9Ac as well as RNA Pol II obtained from differentiating murine hematopoietic cells
Project description:It has now been well established that hematopoietic stem and progenitor cells originate from a specialised subset of endothelium termed hemogenic endothelium (HE) via an endothelial-to-hematopoietic transition. However, the molecular mechanisms determining which endothelial progenitors possess or not this hemogenic potential is currently unknown. In this study, we investigated the changes in hemogenic potential in endothelial progenitors at the early stages of embryonic development. We use a microarray approach to profile the genes regulated between E7.5 and E8.5 embryonic day in the ETV2+FLK1+CD41- compartment. Cells were sorted based on ETV2::GFP+/FLK1+/CD41- immunophenotype from ETV2::GFP embryos at E7.5 and E8.5 developmental stage in triplicates
Project description:Overexpression of transcription factor Sox17 in human ES cells-derived endothelial cells enhances expansion of hemogenic endothelium-like cells.
Project description:The differentiation of human embryonic stem cells to hematopoietic lineages initiates with the specification of hemogenic endothelium, a transient specialized endothelial precursor of all blood cells.Unfortunately, absence of hemogenic endothelium-specific markers as well as lack of consensus in the timing of hemogenic potential analysis and methodologies used to study the hematopoietic potential of this precursor prevents reaching clear and definite conclusions. Here, we demonstrate that the hemogenic potential of the endothelium precursor population sharply decline over the course of the differentiation process. Poly(A) RNA-sequencing on CD31+CD144+ population at day 6, day 8 and day 10 of EB diffferentiation with or without the addition of cytokines. Comparasion with hematopoietic committed population CD31+CD144- from day 10 of EB differentiation.
Project description:The transcription factor RUNX1 is required in the embryo for formation of the adult hematopoietic system. Here we describe the seminal findings that led to the discovery of RUNX1 and of its critical role in blood cell formation in the embryo from hemogenic endothelium. We also present RNA-Seq data demonstrating that hemogenic endothelial cells in different anatomic sites, which produce hematopoietic progenitors with dissimilar differentiation potentials, are molecularly distinct. Hemogenic endothelial cells and non-hemogenic endothelial cells in the yolk sac are more closely related to each other than either are to hemogenic or non-hemogenic endothelial cells in the major arteries. Thus, a major driver of the different lineage potentials of the committed erythro-myeloid progenitors that emerge in the yolk sac, versus hematopoietic stem cells that originate in the major arteries, is likely to be the distinct molecular properties of the hemogenic endothelial cells from which they are derived. We use bioinformatics analyses to predict signaling pathways active in arterial hemogenic endothelium, several of which are functionally validated pathways including Notch, Wnt, and Hedgehog. We also use a novel bioinformatics approach to assemble transcriptional regulatory networks and predict transcription factors that may be specifically involved in hematopoietic cell formation from arterial hemogenic endothelium, which is the origin of the adult hematopoietic system.