Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes.
Project description:Hematopoietic stem and progenitor cell (HSPC) formation and lineage differentiation involve gene expression programs orchestrated by transcription factors and epigenetic regulators. Knockdown of the chromatin remodeler chromodomain-helicase-DNA-binding protein 7 (CHD7) expanded phenotypic HSPCs, erythroid, and myeloid lineages in zebrafish and mouse embryos. CHD7 acts to suppress hematopoietic differentiation in a cell autonomous manner in the embryo and adult. CHD7 chromatin immunoprecipitation in human CD34+ and mouse HSPCs revealed enrichment of binding motifs for hematopoietic transcription factors including Runx1 and GATA factors, and decreased Runx1 occupancy correlated with loss of CHD7 occupancy. CHD7 physically interacts with Runx1 and suppresses Runx1-induced expansion of HSPCs during development, providing both physical and genetic evidence for the Runx1-CHD7 interaction. CHD7 modulates Runx1 activity to provide proper timing and function of HSPCs as they emerge during hematopoietic development or mature in adults, representing a distinct and evolutionarily conserved control mechanism to ensure accurate hematopoietic lineage differentiation. We profiled expression of CHD7 wild-type and deficient adult mice bone marrow long-term hematopoietic stem cells and found genes from several hematopoietic lineages are upregulated.
Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes. Mouse hematopoietic stem cells were purified from bone marrow cells using negative and positive selection with a Magnetic-Activated Cell Sorter (MACS). total RNA and mRNA were purified from the purified cells using Trizol reagent and magnetic oligo dT beads. Double strand cDNAs were synthesized using a cDNA synthesis kit and anchored oligo dT primers. After NlaIII digestion, 3’ cDNAs were isolated and amplified through 16-cycle PCR. SAGE tags were released from the 3’ cDNA after linker ligation. Ditags were formed, concatemerized and cloned into a pZERO vector. Sequencing reactions were performed with the ET sequencing terminator kit. Sequences were collected using a Megabase 1000 sequencer. SAGE tag sequences were extracted using SAGE 2000 software.
Project description:Hematopoietic stem and progenitor cell (HSPC) formation and lineage differentiation involve gene expression programs orchestrated by transcription factors and epigenetic regulators. Knockdown of the chromatin remodeler chromodomain-helicase-DNA-binding protein 7 (CHD7) expanded phenotypic HSPCs, erythroid, and myeloid lineages in zebrafish and mouse embryos. CHD7 acts to suppress hematopoietic differentiation in a cell autonomous manner in the embryo and adult. We performed gene expression analysis to determine the expression of chd7 in adult sorted HSPC populations. Loss of Chd7 in long term hematopoietic stem cells (LT-HSCs) results in upregulation of genes that function in hematopoietic system development and function. Genes representative of each blood lineage including erythroid, myeloid, and lymphoid were upregulated, suggesting that Chd7 deficiency results in LT-HSCs that are more primed for multilineage differentiation. Together with the physical and genetic interaction, the data support a model in which CHD7 interacts with and modulates Runx1 activity to provide proper timing and function of HSPCs as they emerge during hematopoietic development or mature in adults. This represents a distinct and evolutionarily conserved control mechanism to ensure accurate hematopoietic lineage differentiation. We used microarrays to detail the expression of Chd7 in adult sorted HSPC populations.
Project description:Hematopoietic stem and progenitor cell (HSPC) formation and lineage differentiation involve gene expression programs orchestrated by transcription factors and epigenetic regulators. Knockdown of the chromatin remodeler chromodomain-helicase-DNA-binding protein 7 (CHD7) expanded phenotypic HSPCs, erythroid, and myeloid lineages in zebrafish and mouse embryos. CHD7 acts to suppress hematopoietic differentiation in a cell autonomous manner in the embryo and adult. CHD7 chromatin immunoprecipitation in human CD34+ and mouse HSPCs revealed enrichment of binding motifs for hematopoietic transcription factors including Runx1 and GATA factors, and decreased Runx1 occupancy correlated with loss of CHD7 occupancy. CHD7 physically interacts with Runx1 and suppresses Runx1-induced expansion of HSPCs during development, providing both physical and genetic evidence for the Runx1-CHD7 interaction. CHD7 modulates Runx1 activity to provide proper timing and function of HSPCs as they emerge during hematopoietic development or mature in adults, representing a distinct and evolutionarily conserved control mechanism to ensure accurate hematopoietic lineage differentiation.
Project description:Hematopoietic stem and progenitor cell (HSPC) formation and lineage differentiation involve gene expression programs orchestrated by transcription factors and epigenetic regulators. Knockdown of the chromatin remodeler chromodomain-helicase-DNA-binding protein 7 (CHD7) expanded phenotypic HSPCs, erythroid, and myeloid lineages in zebrafish and mouse embryos. CHD7 acts to suppress hematopoietic differentiation in a cell autonomous manner in the embryo and adult. CHD7 chromatin immunoprecipitation in human CD34+ and mouse HSPCs revealed enrichment of binding motifs for hematopoietic transcription factors including Runx1 and GATA factors, and decreased Runx1 occupancy correlated with loss of CHD7 occupancy. CHD7 physically interacts with Runx1 and suppresses Runx1-induced expansion of HSPCs during development, providing both physical and genetic evidence for the Runx1-CHD7 interaction. CHD7 modulates Runx1 activity to provide proper timing and function of HSPCs as they emerge during hematopoietic development or mature in adults, representing a distinct and evolutionarily conserved control mechanism to ensure accurate hematopoietic lineage differentiation.