Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine, Ruijin Hospital Affiliated to Shanghai Jiao Tong University (SJTU) School of Medicine, Shanghai, China.
Department of Rheumatology, Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Cell Death Dis. 2021 Jun 2;12(6):568. doi: 10.1038/s41419-021-03826-1.
GATA2, a key transcription factor in hematopoiesis, is frequently mutated in hematopoietic malignancies. How the GATA2 mutants contribute to hematopoiesis and malignant transformation remains largely unexplored. Here, we report that Gata2-L359V mutation impeded hematopoietic differentiation in murine embryonic and adult hematopoiesis and blocked murine chronic myeloid leukemia (CML) cell differentiation. We established a Gata2-L359V knockin mouse model in which the homozygous Gata2-L359V mutation caused major defects in primitive erythropoiesis with an accumulation of erythroid precursors and severe anemia, leading to embryonic lethality around E11.5. During adult life, the Gata2-L359V heterozygous mice exhibited a notable decrease in bone marrow (BM) recovery under stress induction with cytotoxic drug 5-fluorouracil. Using RNA sequencing, it was revealed that homozygous Gata2-L359V suppressed genes related to embryonic hematopoiesis in yolk sac, while heterozygous Gata2-L359V dysregulated genes related to cell cycle and proliferation in BM LinSca1c-kit cells. Furthermore, through chromatin immunoprecipitation sequencing and transactivation experiments, we found that this mutation enhanced the DNA-binding capacity and transcriptional activities of Gata2, which was likely associated with the altered expression of some essential genes during embryonic and adult hematopoiesis. In mice model harboring BCR/ABL, single-cell RNA-sequencing demonstrated that Gata2-L359V induced additional gene expression profile abnormalities and partially affected cell differentiation at the early stage of myelomonocytic lineage, evidenced by the increase of granulocyte-monocyte progenitors and monocytosis. Taken together, our study unveiled that Gata2-L359V mutation induces defective hematopoietic development and blocks the differentiation of CML cells.
GATA2 是造血过程中的关键转录因子,在造血恶性肿瘤中经常发生突变。GATA2 突变体如何促进造血和恶性转化在很大程度上仍未得到探索。在这里,我们报告 Gata2-L359V 突变阻碍了小鼠胚胎和成体造血中的造血分化,并阻断了小鼠慢性髓性白血病(CML)细胞的分化。我们建立了 Gata2-L359V 敲入小鼠模型,其中纯合 Gata2-L359V 突变导致原始红细胞生成中的主要缺陷,伴有红细胞前体的积累和严重贫血,导致胚胎在 E11.5 左右致死。在成年期,Gata2-L359V 杂合小鼠在使用细胞毒性药物 5-氟尿嘧啶进行应激诱导时,骨髓(BM)恢复明显减少。通过 RNA 测序,发现纯合 Gata2-L359V 抑制了卵黄囊中与胚胎造血相关的基因,而杂合 Gata2-L359V 则使 BM LinSca1c-kit 细胞中与细胞周期和增殖相关的基因失调。此外,通过染色质免疫沉淀测序和转录激活实验,我们发现这种突变增强了 Gata2 的 DNA 结合能力和转录活性,这可能与胚胎和成体造血过程中某些必需基因的改变表达有关。在携带 BCR/ABL 的小鼠模型中,单细胞 RNA 测序表明 Gata2-L359V 诱导了额外的基因表达谱异常,并在髓系早期阶段部分影响细胞分化,表现为粒细胞-单核细胞祖细胞和单核细胞增多。总之,我们的研究揭示了 Gata2-L359V 突变诱导造血发育缺陷并阻断 CML 细胞的分化。