Project description:This SuperSeries is composed of the following subset Series: GSE16676: Rescue of murine Gata1s mutant M7 leukemic cells by full-length Gata1 GSE16677: Gene expression profiling of Down Syndrome (DS)-AMKL and non-DS AMKL samples GSE16679: Plag1 overexpression cooperates with Evi1 overexpression and Gata1s mutation in leading to M7 leukemia GSE16682: Murine M7 leukemia derived from retroviral insertional mutagenesis of Gata1s fetal progenitors GSE16684: Murine M7 leukemia derived from retroviral insertional mutagenesis of Gata1s fetal progenitors depends on IGF signaling Refer to individual Series
Project description:In this project, we studied a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the GATA1 transcription factor (called GATA1s mutation). The model was generated through retroviral insertional mutagenesis in Gata1s mutant fetal liver progenitors. In this study, we analyzed the dependency of these leukemic cells on the Gata1s mutant protein. Here we report Gata1s mutant leukemic cells were dependent on this mutant protein. Introduction of the full-length Gata1 protein to these cells led to their reduced proliferation and increased differentiation along the megakaryocytic lineage. We transduced leukemic cells with Gata1/estrogen receptor fusion cDNA (Gata1-ER) and generated stable cell lines. Addition of beta-estradiol to culture medium led to activation of the full-length Gata1 protein in synchronized leukemic cells. Gene expression profiles were collected at multiple time points.
Project description:In this project, we studied a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the GATA1 transcription factor (called GATA1s mutation). The model was generated through retroviral insertional mutagenesis in Gata1s mutant fetal liver progenitors. In this study, we analyzed the dependency of these leukemic cells on the Gata1s mutant protein. Here we report Gata1s mutant leukemic cells were dependent on this mutant protein. Introduction of the full-length Gata1 protein to these cells led to their reduced proliferation and increased differentiation along the megakaryocytic lineage.
Project description:The goal of this study is to derive a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the hematopoietic transcription factor, GATA1 (called GATA1s mutation). We achieved this through transduction of Gata1s mutant fetal progenitors by MSCV-based retrovirus expressing a GFP marker, followed by in vitro selection (for immortalized cell lines), and then in vivo selection (for transformed cell lines) through transplantation. Here we report one such cell line [T6(6)] that gives rise to megakaryocytic leukemia (M7 leukemia) upon transplantation. Since the leukemic cells were retrovirally tagged with a GFP reporter, we sorted GFP+ leukemic blasts and generated their expression profiles by microarray.
Project description:We used chromatin immunoprecipitation sequencing (ChIP-seq) to compare genome-wide binding profiles of GATA1fl and GATA1s in G1ME cells, which are immortalized, developmentally arrested megakaryocyte-erythroid progenitors (MEPs) derived from in vitro differentiation of murine Gata1- ES cells. Although the truncation in GATA1s leaves the DNA binding domain intact, GATA1s fails to broadly occupy erythroid specific regulatory regions. These observations point to lineage specific co-factor associations essential for normal chromatin occupancy and provide mechanistic insights into how GATA1s mutations cause human disease. We performed ChIP-seq on G1ME cells 42 hours after retroviral transfer of HA-tagged full-length GATA1 (GATA1fl) or GATA1s cDNAs (2 replicates each). At this time point, there was no apparent difference in the cell surface phenotypes between GATA1fl and GATA1s-expressing cells. For each ChIP-seq replicate we obtained a matching input sample (non-ChIP DNA) as a control.
Project description:The goal of this study is to derive a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the hematopoietic transcription factor, GATA1 (called GATA1s mutation). We achieved this through transduction of Gata1s mutant fetal progenitors by MSCV-based retrovirus expressing a GFP marker, followed by in vitro selection (for immortalized cell lines), and then in vivo selection (for transformed cell lines) through transplantation. Here we report one such cell line [T6(6)] that gives rise to megakaryocytic leukemia (M7 leukemia) upon transplantation.
Project description:The goal of this study is to derive a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the hematopoietic transcription factor, GATA1 (called GATA1s mutation). We achieved this through transduction of Gata1s mutant fetal progenitors by MSCV-based retrovirus expressing a GFP marker, followed by in vitro selection (for immortalized cell lines), and then in vivo selection (for transformed cell lines) through transplantation. Here we report one such cell line [T6(6)] that gives rise to megakaryocytic leukemia (M7 leukemia) upon transplantation. We show knockdown of IGF1R in these cells leads to their reduced proliferation.
Project description:This SuperSeries is composed of the SubSeries listed below. Germline GATA1 mutations resulting in the production of an amino-truncated protein termed GATA1s (for “short”) cause congenital hypoplastic anemia. Similar somatic mutations promote transient myeloproliferative disease and acute megakaryoblastic leukemia in trisomy 21 patients. Here we show that induced pluripotent stem cells (iPSCs) from patients with GATA1-truncating mutations exhibit impaired erythroid potential but enhanced megakaryopoiesis and myelopoiesis, faithfully recapitulating the major phenotypes of associated diseases. Similarly, GATA1s promotes megakaryopoiesis but not erythropoiesis in developmentally arrested Gata1- murine megakaryocyte-erythroid progenitors derived from murine embryonic stem cells (ESCs). Transcriptome studies demonstrate a selective deficiency in the ability of GATA1s to activate erythroid-expressed genes within populations of hematopoietic progenitors. Although its DNA binding domain is intact, chromatin immunoprecipitation studies show that GATA1s binding at specific erythroid regulatory regions is impaired, while binding at many non-erythroid sites, including megakaryocytic and myeloid target genes, is normal. These observations point to lineage specific GATA1 co-factor associations essential for normal chromatin occupancy and provide mechanistic insights into how GATA1s mutations cause human disease. More broadly, our studies underscore the value of ESCs and iPSCs to recapitulate and study disease phenotypes.
Project description:The goal of this study is to derive a mouse model of human Down Syndrome (DS) megakaryocytic leukemia involving mutations in the hematopoietic transcription factor, GATA1 (called GATA1s mutation). We achieved this through transduction of Gata1s mutant fetal progenitors by MSCV-based retrovirus expressing a GFP marker, followed by in vitro selection (for immortalized cell lines), and then in vivo selection (for transformed cell lines) through transplantation. Here we report one such cell line [T6(6)] that gives rise to megakaryocytic leukemia (M7 leukemia) upon transplantation. We show knockdown of IGF1R in these cells leads to their reduced proliferation. IGF1R was knocked down in these cells using a tet-regulatable shRNA-based lentiviral system. Cells infected with the empty vector or those infected with shRNA construct against IGF1R but in the absence of Doxycycline were used as controls. The latter cells in the presence of Doxycycline exhibited reduced IGF1R at the RNA level.
Project description:This SuperSeries is composed of the SubSeries listed below. Germline GATA1 mutations resulting in the production of an amino-truncated protein termed GATA1s (for M-bM-^@M-^\shortM-bM-^@M-^]) cause congenital hypoplastic anemia. Similar somatic mutations promote transient myeloproliferative disease and acute megakaryoblastic leukemia in trisomy 21 patients. Here we show that induced pluripotent stem cells (iPSCs) from patients with GATA1-truncating mutations exhibit impaired erythroid potential but enhanced megakaryopoiesis and myelopoiesis, faithfully recapitulating the major phenotypes of associated diseases. Similarly, GATA1s promotes megakaryopoiesis but not erythropoiesis in developmentally arrested Gata1- murine megakaryocyte-erythroid progenitors derived from murine embryonic stem cells (ESCs). Transcriptome studies demonstrate a selective deficiency in the ability of GATA1s to activate erythroid-expressed genes within populations of hematopoietic progenitors. Although its DNA binding domain is intact, chromatin immunoprecipitation studies show that GATA1s binding at specific erythroid regulatory regions is impaired, while binding at many non-erythroid sites, including megakaryocytic and myeloid target genes, is normal. These observations point to lineage specific GATA1 co-factor associations essential for normal chromatin occupancy and provide mechanistic insights into how GATA1s mutations cause human disease. More broadly, our studies underscore the value of ESCs and iPSCs to recapitulate and study disease phenotypes. Refer to individual Series