Project description:Gata2, a zinc finger TF, is essential for the generation and survival of HSCs in the embryo and has been implicated in the pathogenesis of AML, yet the requirement for Gata2 in adult HSCs and LSCs remains unclear. Using a conditional mouse model where Gata2 was deleted specifically in hematopoietic cells, we show that knockout of Gata2 leads to a rapid and complete cell-autonomous loss of adult HSCs. We then performed RNA-seq in sorted HSCs (LSK CD48- CD150+) from control and Gata2+/fl;Vav-iCre+ 8-to-10-week old mice.
Project description:Gata2, a zinc finger TF, is essential for the generation and survival of HSCs in the embryo and has been implicated in the pathogenesis of AML, yet the requirement for Gata2 in adult HSCs and LSCs remains unclear. Using a conditional mouse model where Gata2 was deleted specifically in hematopoietic cells, we show that knockout of Gata2 leads to a rapid and complete cell-autonomous loss of adult HSCs. In Meis1a/Hoxa9 driven AML, deletion of Gata2 impedes maintenance and self-renewal of LSCs. We then performed RNA-seq from sorted control and Gata2 KO LSCs (CD45.2+ c-Kit+) after pIpC treatment in transplanted mice.
Project description:Background and Purpose: Constitutional GATA2 deficiency caused by heterozygous germline GATA2 mutation has a broad spectrum of clinical phenotypes including systemic infections, lymphedema, cytopenias, MDS and AML. A comprehensive profiling of transcriptome of hematopoiesis in GATA2 deficiency is currently lacking. Methods: We performed single-cell RNA sequencing of sorted bone marrow CD34+ hematopoietic stem and progenitor cells (HSPCs) from eight GATA2 deficiency patients, who had various well characterized GATA2 mutations and clinically manifest myelodysplasia. We characterized transcriptomes in lineages, computationally defined cells with chromosomal abnormalities, and described gene expression of these cells. Results: Mapping patients’ cells onto normal hematopoiesis, we observed preferred deficiency in lymphoid and myeloid progenitors, which also was evidenced in loss of heterogeneity in gene correlations. HSPCs in patients exhibited distinct gene expression pattern and gene coexpression pattern compared with its counterparts in healthy donors. Distinct lineages show different transcriptional profiles resulting from GATA2 mutations. HSCs in patients exhibited dysregulated genes in apoptosis, cell cycle and quiescence, and had increased expression of erythroid/megakaryocytic priming programs and decreased lymphoid priming programs. Thus, the prominent deficiency in myeloid/lymphoid lineages in GATA2 deficiency was partly due to expression of aberrant gene programs in HSCs prior to lineage commitment. We computationally defined cells with chromosomal abnormalities and described gene expression of these cells. DNA repair genes were downregulated in trisomy 8 cells, possibly rendering these cells vulnerable to second-hit somatic mutations and additional chromosomal abnormalities. Cells with complex cytogenetics had defects in multi-lineage differentiation and cell cycle. Conclusion: Germline GATA2 mutations modulate gene expression and change gene coexpression patterns. Distinct lineages show different transcriptional profiles resulting from GATA2 mutations. The prominent deficiency in myeloid/lymphoid lineages in GATA2 deficiency was partly due to expression of aberrant gene programs in HSCs prior to lineage commitment.
Project description:To clarify the role of Gata2 in the development of Cbfb-MYH11 induced leukemia, we generated conditional Cbfb-MYH11 knockin mice with Gata2 heterozygous knockout. Leukemic cells with Gata2 heterozygous knockout gained higher number of genetic mutations and showed more aggressive phenotype in both primary and transplanted recipient mice. We compared gene expression profilings between Gata2+/+ and Gata2+/f leukemic cells with Cbfb-MYH11.
Project description:The Gata2 transcription factor is a pivotal regulator of hematopoietic stem cell (HSC) development and maintenance. Gata2 functions in the embryo during endothelial cell to hematopoietic cell transition (EHT) to affect hematopoietic cluster, HPC and HSC formation. Although previous studies of cell populations phenotypically enriched in HPCs and HSCs show expression of Gata2, there has been no direct study of Gata2 expressing cells during normal hematopoiesis. In this study we generate a Gata2 Venus reporter mouse model with unperturbed Gata2 expression to examine the hematopoietic function and transcriptome of Gata2 expressing and nonexpressing cells. Gata2Venus- HPCs 1 replicate, Gata2Venus+ HPCs 1 replicate