Gata-1 Knock Down - Wild Type Megakaryocyte Gene Expression
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE2527 | GEO | 2005/05/06
SECONDARY ACCESSION(S): PRJNA92071
REPOSITORIES: GEO
Similar Datasets
Project description:Hematopoietic progenitor cells were isolated from 13.5 day mouse fetal livers by lineage depletion and expanded for three days. Fetal livers were isolated from both wild type and Gata-1 knock embryos. Gata-1 knock embryos contain a deletion of the Gata-1 promoter sequence that results in undetectable levels of Gata-1 protein specifically in the megakaryocyte lineage. Following progenitor outgrowth megakaryocytes were enriched in a differentiation media for three days and isolated on a discontinuous BSA gradient. The resulting megakaryocytes were >90% pure as determined by acetylcholinesterase staining. These cells were lysed in Trizol and the resulting RNA was used for hybridization.
2007-09-04 | E-GEOD-2527 | biostudies-arrayexpress
Project description:Background: Children with Down syndrome (DS) are predisposed to acute megakaryoblastic leukemia (AMKL, or AML M7) and a related myeloid disorder, referred to as transient myeloproliferative disorder (TMD), or transient leukemia (TL). Recently, acquired mutations in the erythroid/megakaryocytic lineage-specific transcription factor GATA-1 have been identified in megakaryoblasts from virtually all DS patients with AMKL (DS-AMKL), as well as in nearly all DS neonates with TMD. These mutations prevent synthesis of full-length GATA-1, but lead to synthesis of a truncated GATA-1 protein (GATA-1s) that lacks the N-terminal transactivation domain. To determine the in vivo requirement of GATA-1 N-terminal domain in hematopoiesis and to model DS megakaryocytic leukemia initiated by GATA-1 mutation, we generated a GATA-1 knockin allele with a truncation at this domain (GATA-1deltaN). ES cells bearing this mutant allele generated a unique type of large Thrombopoietin (Tpo)-dependent megakaryocytes-containing colonies, when differentiated in vitro. Fetal livers from mice carrying this mutant allele contained elevated numbers of CD41+ cells throughout embryonic development, especially during mid-gestation. In in vitro hematopoietic colony assays, mutant cells from yolk sacs and mid-gestation fetal livers gave rise to a large number of macroscopic hyperproliferative megakaryocytic colonies (CFU-MKs). Consistent with that, when mutant fetal liver progenitors were cultured in liquid medium in the presence of Tpo, the derived megakaryocytes displayed marked hyperproliferation and grew for longer period of time than WTs. Specific aims: To understand the molecular basis for the megakaryocytic hyperproliferation phenotype of the GATA-1deltaN mutants, we plan to profile gene expression patterns of fetal liver-derived primary megakaryocytes and megakaryocytic progenitors from the GATA-1deltaN mutants and compare them with WTs, as well as GATA-1deltaNeodeltaHS mutants (GATA-1– megakaryocytes). Experimental design: E12.5 fetal livers were harvested from either GATA-1 WT and mutant embryos. Single cell suspensions were made from these livers and the cells were cultured in liquid medium in the presence of Tpo for 3 days. On day 3, primary megakaryocytes were enriched by a BSA gradient, and further enriched by anti-CD41 antibody and magnetic microbeads. Megakaryocytic progenitors were collected by FACS sorting for small cells in the same culture that express low level of CD41. Total RNAs were then prepared from these two populations and submitted for microarray profiling. Conclusions: When examining genes that are normally upregulated upon megakaryocyte differentiation (many of this class are megakaryocyte-specific genes), we found in GATA-1deltaN megakaryocytes, the majority of these genes are upregulated, although not to the full extent as seen in WTs. In contrast, this class of genes is largely not upregulated in GATA-1deltaNeodeltaHS megakaryocytes, which are blocked at an immature stage of differentiation. Genes that are downregulated during megakaryocyte differentiation include those that are normally repressed by GATA-1. Among genes that are not properly downregulated in GATA-1deltaN megakaryocytes, five transcription factors (Myc, Myb, GATA-2, PU.1, Ikaros) are of particular interest. Inadequate GATA-1s-mediated repression of transcription factors required for proliferation of hematopoietic progenitors (Myc, Myb and GATA-2) and for specifying lineage choices other than megakaryocyte/erythrocyte (PU.1 and Ikaros) may contribute to hyperproliferation of GATA-1deltaN megakaryocytes. Keywords = GATA-1 Keywords = megakaryocyte Keywords = mouse model Keywords: other
2005-05-14 | GSE2433 | GEO
Project description:Background: Children with Down syndrome (DS) are predisposed to acute megakaryoblastic leukemia (AMKL, or AML M7) and a related myeloid disorder, referred to as transient myeloproliferative disorder (TMD), or transient leukemia (TL). Recently, acquired mutations in the erythroid/megakaryocytic lineage-specific transcription factor GATA-1 have been identified in megakaryoblasts from virtually all DS patients with AMKL (DS-AMKL), as well as in nearly all DS neonates with TMD. These mutations prevent synthesis of full-length GATA-1, but lead to synthesis of a truncated GATA-1 protein (GATA-1s) that lacks the N-terminal transactivation domain. To determine the in vivo requirement of GATA-1 N-terminal domain in hematopoiesis and to model DS megakaryocytic leukemia initiated by GATA-1 mutation, we generated a GATA-1 knockin allele with a truncation at this domain (GATA-1deltaN). ES cells bearing this mutant allele generated a unique type of large Thrombopoietin (Tpo)-dependent megakaryocytes-containing colonies, when differentiated in vitro. Fetal livers from mice carrying this mutant allele contained elevated numbers of CD41+ cells throughout embryonic development, especially during mid-gestation. In in vitro hematopoietic colony assays, mutant cells from yolk sacs and mid-gestation fetal livers gave rise to a large number of macroscopic hyperproliferative megakaryocytic colonies (CFU-MKs). Consistent with that, when mutant fetal liver progenitors were cultured in liquid medium in the presence of Tpo, the derived megakaryocytes displayed marked hyperproliferation and grew for longer period of time than WTs. Specific aims: To understand the molecular basis for the megakaryocytic hyperproliferation phenotype of the GATA-1deltaN mutants, we plan to profile gene expression patterns of fetal liver-derived primary megakaryocytes and megakaryocytic progenitors from the GATA-1deltaN mutants and compare them with WTs, as well as GATA-1deltaNeodeltaHS mutants (GATA-1megakaryocytes). Experimental design: E12.5 fetal livers were harvested from either GATA-1 WT and mutant embryos. Single cell suspensions were made from these livers and the cells were cultured in liquid medium in the presence of Tpo for 3 days. On day 3, primary megakaryocytes were enriched by a BSA gradient, and further enriched by anti-CD41 antibody and magnetic microbeads. Megakaryocytic progenitors were collected by FACS sorting for small cells in the same culture that express low level of CD41. Total RNAs were then prepared from these two populations and submitted for microarray profiling. Conclusions: When examining genes that are normally upregulated upon megakaryocyte differentiation (many of this class are megakaryocyte-specific genes), we found in GATA-1deltaN megakaryocytes, the majority of these genes are upregulated, although not to the full extent as seen in WTs. In contrast, this class of genes is largely not upregulated in GATA-1deltaNeodeltaHS megakaryocytes, which are blocked at an immature stage of differentiation. Genes that are downregulated during megakaryocyte differentiation include those that are normally repressed by GATA-1. Among genes that are not properly downregulated in GATA-1deltaN megakaryocytes, five transcription factors (Myc, Myb, GATA-2, PU.1, Ikaros) are of particular interest. Inadequate GATA-1s-mediated repression of transcription factors required for proliferation of hematopoietic progenitors (Myc, Myb and GATA-2) and for specifying lineage choices other than megakaryocyte/erythrocyte (PU.1 and Ikaros) may contribute to hyperproliferation of GATA-1deltaN megakaryocytes.
2007-08-31 | E-GEOD-2433 | biostudies-arrayexpress
Project description:Whole fetal livers were collected from mouse fetuses at embryonic day 14.5 (E14.5), and single-cell suspensions were prepared by successive passage through 18-, 21 and 23-gauge needles. Fetal liver cells were maintained in Dulbecco modified Eagle medium (DMEM; Invitrogen) supplemented with 10% fetal bovine serum (FBS; Invitrogen), 100 U/ml penicillin, 100M-BM-5g/ml streptomycin, and 50ng/ml recombinant human thrombopoietin (TPO; Peprotech). After 5 days of culture, megakaryocytes were purified using a discontinuous bovine serum albumin gradient (BSA, SigmaM-bM-^@M-^SAldrich; 3%, 1.5%, and 0%). Total RNA was isolated with TriM-bM-^@M-^SReagent (MRC) following manufacturerM-bM-^@M-^Ys instructions, and its quality was assessed with NDM-bM-^@M-^S1000 Nanodrop (Peqlab) and on a 1.5% agarose gel. Gene expression was measured in primary megakaryocytes cultured from miR-142-/- fetal livers and wild type fetal livers at E14.5. Two independent experiments were performed.
2014-06-11 | E-GEOD-52141 | biostudies-arrayexpress
Project description:Whole fetal livers were collected from mouse fetuses at embryonic day 14.5 (E14.5), and single-cell suspensions were prepared by successive passage through 18-, 21 and 23-gauge needles. Fetal liver cells were maintained in Dulbecco modified Eagle medium (DMEM; Invitrogen) supplemented with 10% fetal bovine serum (FBS; Invitrogen), 100 U/ml penicillin, 100µg/ml streptomycin, and 50ng/ml recombinant human thrombopoietin (TPO; Peprotech). After 5 days of culture, megakaryocytes were purified using a discontinuous bovine serum albumin gradient (BSA, Sigma–Aldrich; 3%, 1.5%, and 0%). Total RNA was isolated with Tri–Reagent (MRC) following manufacturer’s instructions, and its quality was assessed with ND–1000 Nanodrop (Peqlab) and on a 1.5% agarose gel.
2014-06-11 | GSE52141 | GEO
Project description:DS children have a 500-fold increased risk for developing acute megakaryoblastic leukemia (AMKL). Around 10% of DS newborns have a transient myeloproliferative disorder (TMD) that resolves spontaneously. Somatic mutations acquired during fetal hematopoiesis in the GATA1 transcription factor are detected in megakaryoblasts from all the DS TMDs or AMKLs. GATA1 is an X chromosome transcription factor essential for the development of multiple hematopoietic lineages. Loss of GATA1 results in embryonic lethality due to severe anemia. The GATA1 mutations result in the expression of a shorter isoform, GATA1s. Replacement of GATA1 with GATA1s causes transient proliferation of immature fetal megakaryocytic progenitors. The Hsa21 ETS transcription factor, ERG, is expressed in megakaryocytes and erythrocytes and is involved in several types of cancer. Mutation in GATA1 gene leading to expression of the short isoform (GATA1s) that occurs on the background of trisomy 21 is regarded as one of the driving forces for megakaryocytic expansion observed in DS fetal livers. ERG, which is located on chromosome 21, is considered one of the leading candidates to cooperate with GATA1 mutation in the generation of DS AMKL. To study the in vivo cooperation between ERG and GATA1 isoforms, we crossed the ERG transgenic mice with the GATA1s Knock-in mice (GATA null background). We found that males expressing both ERG and the short isoform of GATA1(GATA1s) died in uterus between embryonic days E121/2 and E141/2.We studied erythropoiesis and megakaryopoiesis in fetal livers from the different genotypes generated from our cross. We used expression array to study the specific interaction of ERG with the different GATA1 isoforms in fetal livers from E121/2 and E141/2 and identify ERG, GATA1 and GATA1s target genes by comparing sets of genes that are activated or repressed in the presence of ERG and the two isoforms of GATA1.
2013-12-31 | E-GEOD-46481 | biostudies-arrayexpress
Project description:Whole livers were collected from mouse fetuses at embryonic day 13.5 (E13.5), and single-cell suspensions were prepared by successive passage through 25-gauge needles. Fetal liver cells were maintained in RPMI1640 (Wako, Osaka, Japan) supplemented with 20% charcoal-stripped fetal bovine serum (FBS), 100 U/ml penicillin, 100µg/ml streptomycin, and 50ng/ml recombinant human thrombopoietin (TPO) (generously provided by Kyowa Hakko Kirin Co. Ltd.). Megakaryocytes were harvested for RNA purification from a day-3 culture. CD41+ cells were enriched using biotinylated anti-CD41 antibody (Serotec; clone MWReg30) and streptavidin-coupled Dynabeads (Dynal Biotech ASA) from a culture of E13.5 fetal liver cells of WT and p45–/– mice. Total RNA was purified from the sorted CD41+ cells. Gene expression was measured in primary megakaryocytes cultured from p45-/- fetal livers and wild type fetal livers at E13.5. Three independent experiments were performed.
2013-08-07 | E-GEOD-35645 | biostudies-arrayexpress
Project description:Rb null embryos exhibit defective fetal liver erythropoiesis. We used microarrays to compare Wt and Rb null fetal livers and to analyse gene expression differences which accompany and may underlie Rb null fetal liver degeneration, erythroid failure, and erythropoietic island dissolution. We used microarrays to compare Wt and Rb null fetal livers and analyse gene expression changes which accompany and may underlie fetal liver. Keywords: retinoblastoma, fetal liver, erythroblast, macrophage, cell death
2007-06-05 | GSE6787 | GEO
Project description:ChIP-seq assay was performed with anti-p45 antibody using in vitro cultured primary megakaryocytes to identify direct p45 target genes in megakaryocytes. This analysis revealed genes that regulate platelet function, which were not known previously to be p45-regulated. ChIP was performed using a day-3 primary culture of megakaryocytes from E13.5 fetal livers of wild-type mice with an anti-p45 antibody.
2013-11-01 | E-GEOD-42249 | biostudies-arrayexpress
Project description:DS children have a 500-fold increased risk for developing acute megakaryoblastic leukemia (AMKL). Around 10% of DS newborns have a transient myeloproliferative disorder (TMD) that resolves spontaneously. Somatic mutations acquired during fetal hematopoiesis in the GATA1 transcription factor are detected in megakaryoblasts from all the DS TMDs or AMKLs. GATA1 is an X chromosome transcription factor essential for the development of multiple hematopoietic lineages. Loss of GATA1 results in embryonic lethality due to severe anemia. The GATA1 mutations result in the expression of a shorter isoform, GATA1s. Replacement of GATA1 with GATA1s causes transient proliferation of immature fetal megakaryocytic progenitors. The Hsa21 ETS transcription factor, ERG, is expressed in megakaryocytes and erythrocytes and is involved in several types of cancer. Mutation in GATA1 gene leading to expression of the short isoform (GATA1s) that occurs on the background of trisomy 21 is regarded as one of the driving forces for megakaryocytic expansion observed in DS fetal livers. ERG, which is located on chromosome 21, is considered one of the leading candidates to cooperate with GATA1 mutation in the generation of DS AMKL. To study the in vivo cooperation between ERG and GATA1 isoforms, we crossed the ERG transgenic mice with the GATA1s Knock-in mice (GATA null background). We found that males expressing both ERG and the short isoform of GATA1(GATA1s) died in uterus between embryonic days E121/2 and E141/2.We studied erythropoiesis and megakaryopoiesis in fetal livers from the different genotypes generated from our cross.
2013-12-31 | GSE46481 | GEO