Project description:The formation of hematopoietic cells relies on the chromatin remodeling activities of ISWI ATPase SMARCA5 (SNF2H) and its complexes. The Smarca5 null and conditional alleles have been used to study its functions in embryonic and organ development in mice. These mouse model phenotypes vary from embryonic lethality of constitutive knockout to less severe phenotypes observed in tissue-specific Smarca5 deletions, e.g., in the hematopoietic system. Here we show that, in a gene dosage-dependent manner, the hypomorphic allele of SMARCA5 (S5tg) can rescue not only the developmental arrest in hematopoiesis in the hCD2iCre model but also the lethal phenotypes associated with constitutive Smarca5 deletion or Vav1iCre-driven conditional knockout in hematopoietic progenitor cells. Interestingly, the latter model also provided evidence for the role of SMARCA5 expression level in hematopoietic stem cells, as the Vav1iCre S5tg animals accumulate stem and progenitor cells. Furthermore, their hematopoietic stem cells exhibited impaired lymphoid lineage entry and differentiation. This observation contrasts with the myeloid lineage which is developing without significant disturbances. Our findings indicate that animals with low expression of SMARCA5 exhibit normal embryonic development with altered lymphoid entry within the hematopoietic stem cell compartment.
Project description:Epigenetic regulation exerts a crucial role in maintaining the balance between self-renewal and differentiation of hematopoietic stem cells (HSCs), thereby sustaining normal hematopoiesis. Although emerging evidence has demonstrated the contribution of RNA N4-acetylcytidine (ac4C) modification and its catalytic enzyme Nat10 to numerous biological processes, particularly tumorigenesis, the function of Nat10 in normal hematopoiesis remain unexplored. In this study, we characterize the function of Nat10 in hematopoietic stem and progenitor cells (HSPCs) using low input proteomics and reveal a key role of Nat10 in the maintenance of HSCs.
Project description:This is a mathematical model describing the hematopoietic lineages with leukemia lineages, as controlled by end-product negative feedback inhibition. Variables include hematopoietic stem cells, progenitor cells, terminally differentiated HSCs, leukemia stem cells, and terminally differentiated leukemia stem cells.
Project description:RNA expression analysis on purified human long-term and short-term hematopoietic stem cells (LT-HSC, ST-HSC), common myeloid and megakaryocyte-erythrocyte progenitor cells (CMP, MEP) using microarrays. FACS-purified hematopoietic stem and progenitor cell (HSPC) subsets were analyzed for changes in RNA expression using NimbleGen gene expression microarrays. Analysis of RNA expression of bone marrow-derived HSPC subsets of healthy human donors.
Project description:RNA expression analysis on purified human long-term and short-term hematopoietic stem cells (LT-HSC, ST-HSC), common myeloid and megakaryocyte-erythrocyte progenitor cells (CMP, MEP) using microarrays. FACS-purified hematopoietic stem and progenitor cell (HSPC) subsets were analyzed for changes in RNA expression using NimbleGen gene expression microarrays.
