This SuperSeries is composed of the SubSeries listed below.
Identification of biologically relevant enhancers in human erythroid cells.
Specimen part
View SamplesIdentification of cell-type specific enhancers is important for understanding the regulation of programs controlling cellular development and differentiation. Enhancers are typically marked by the co-transcriptional activator protein p300 or by groups of cell-expressed transcription factors. We hypothesized that a unique set of enhancers regulates gene expression in human erythroid cells, a highly specialized cell type evolved to provide adequate amounts of oxygen throughout the body. Using chromatin immunoprecipitation followed by massively parallel sequencing, genome-wide maps of candidate enhancers were constructed for p300 and four transcription factors, GATA1, NF-E2, KLF1, and SCL, using primary human erythroid cells. These data were combined with gene expression analyses and candidate enhancers identified. Consistent with their predicted function as candidate enhancers, there was statistically significant enrichment of p300 and combinations of co-localizing erythroid transcription factors within 1-50 kb of the TSS of genes highly expressed in erythroid cells. Candidate enhancers were also enriched near genes with known erythroid cell function or erythroid cell phenotypes. Candidate enhancers exhibited only moderate conservation with mouse and minimal conservation with nonplacental vertebrates. Candidate enhancers were mapped to a data set of erythroid-associated, biologically relevant, SNPs from the GWAS catalog of the NHGRI. Fourteen candidate enhancers, representing 10 genetic loci, mapped to sites associated with biologically relevant erythroid traits. Fragments from these loci directed statistically significant expression in reporter gene assays. Identification of enhancers in human erythroid cells will allow a better understanding of erythroid cell development, differentiation, structure, and function, and provide insights into inherited and acquired hematologic disease.
Identification of biologically relevant enhancers in human erythroid cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Function of GATA factors in the adult mouse liver.
Specimen part, Treatment
View SamplesG1E cells are a Gata-1 erythroid-committed cell line derived from targeted disruption of Gata-1 in embryonic stem cells. The ER4 subclone contains an inducible form of Gata-1 (Gata-1-ER, Gata-1 fused to the estradiol receptor ligand binding domain). We performed transcriptome analysis using this cell line. Estradiol was added to culture medium triggering synchronous and homogenous differentiation. At various time points, RNA was sampled and analyzed using the Affymetrix MG-U74Av2 platform. Three biological replicas (A,B, and C) were performed. The thirty hour time course corresponds to development from the late BFU-E stage through the orthochromatic erythroblast stage.
Global regulation of erythroid gene expression by transcription factor GATA-1.
No sample metadata fields
View SamplesAnalysis of changes in gene expression following hepatocyte specific deletion of GATA4 and GATA6 in adult mice. Results showed that the subset of differentially expressed genes had liver specific ontologies.
Function of GATA factors in the adult mouse liver.
Specimen part
View SamplesAnalysis of changes in gene expression following hepatocyte specific deletion of GATA4 in adult mice. Results showed that the subset of differentially expressed genes had liver specific ontologies.
Function of GATA factors in the adult mouse liver.
Specimen part, Treatment
View SamplesCombinatorial 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, TAL1, and FLI1) and three diagnostic histone modification marks with the gene expression changes that occur during development of primary cultured megakaryocytes (MEG) and primary 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, TAL1, FLI1, ERG, RUNX1, LMO2) binding to MEG-associated cis-regulatory modules (CRMs) in multipotential 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 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 progenitor via overlapping and divergent functions of shared hematopoietic transcription factors.
Divergent functions of hematopoietic transcription factors in lineage priming and differentiation during erythro-megakaryopoiesis.
Specimen part
View SamplesCombinatorial 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.
Divergent functions of hematopoietic transcription factors in lineage priming and differentiation during erythro-megakaryopoiesis.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Functions of BET proteins in erythroid gene expression.
Specimen part, Treatment
View SamplesRole of bromodomain and extra-terminal motif (BET) proteins in GATA1-null erythrolbasts (G1E) and in differentiation induced by activation of conditional GATA1 tested by addition of BET inhibitor JQ1 (250nM)
Functions of BET proteins in erythroid gene expression.
No sample metadata fields
View Samples