SHP2 tyrosine phosphatase stimulates CEBPA gene expression to mediate cytokine-dependent granulopoiesis.
SHP2 tyrosine phosphatase stimulates CEBPA gene expression to mediate cytokine-dependent granulopoiesis.
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DOI：
10.1182/blood-2011-01-331157
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发表时间：
2011-08
期刊：
影响因子：
20.3
通讯作者：
Li Zhang;A. Friedman
中科院分区：
文献类型：
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作者：
Li Zhang;A. Friedman
G-CSF信号有助于粒细胞谱系特化。我们以前发现，G-CSF诱导SHP 2酪氨酸磷酸化和SHP 1/SHP 2的化学抑制减少CFU-G和阻止G-CSF但不是M-CSF激活ERK。我们现在发现，在32 Dcl 3粒细胞系中，SHP 2 shRNA敲低降低了ERK激活，减少了CEBPA蛋白和RNA表达以及启动子组蛋白乙酰化，并抑制了粒细胞生成。外源性shRNA抗性的SHP 2挽救了SHP 2敲低的这些效应，外源性C/EBPα挽救了粒细胞标记物，外源性RUNX 1挽救了C/EBPα。ERK 1和ERK 2敲低的32 Dcl 3细胞系保持正常的C/EBPα水平，并在G-CSF中正常分化，尽管也具有降低的增殖。SHP 2敲除可降低在TPO、Flt 3配体和SCF中培养的谱系阴性小鼠骨髓细胞中的CEBPA水平，而不影响细胞扩增速率。在转移至IL-3、IL-6和SCF以诱导骨髓生成时，通过SHP 2敲低，粒细胞RNA的水平降低，单核细胞特异性RNA增加，并且在甲基纤维素中形成的CFU-G和在液体培养物中发育的粒细胞的百分比降低。总之，SHP 2是诱导C/EBPα表达和粒细胞生成所必需的，以响应G-CSF或其他细胞因子，而不依赖于SHP 2介导的ERK激活。
G-CSF signals contribute to granulocyte lineage specification. We previously found that G-CSF induces SHP2 tyrosine phosphorylation and that chemical inhibition of SHP1/SHP2 reduces CFU-G and prevents G-CSF but not M-CSF activation of ERK. We now find that SHP2 shRNA knockdown in the 32Dcl3 granulocytic line reduces ERK activation, diminishes CEBPA protein and RNA expression and promoter histone acetylation, and inhibits granulopoiesis. Exogenous, shRNA-resistant SHP2 rescues these effects of SHP2 knockdown, exogenous C/EBPα rescues granulocytic markers, and exogenous RUNX1 rescues C/EBPα. 32Dcl3 lines with knockdown of ERK1 and ERK2 retain normal levels of C/EBPα and differentiate normally in G-CSF despite also having reduced proliferation. SHP2 knockdown reduces CEBPA levels in lineage-negative murine marrow cells cultured in TPO, Flt3 ligand, and SCF, without affecting the rate of cell expansion. On transfer to IL-3, IL-6, and SCF to induce myelopoiesis, levels of granulocytic RNAs are reduced and monocyte-specific RNAs are increased by SHP2 knockdown, and there is a reduction in the percentage of CFU-G that form in methylcellulose and of granulocytes that develop in liquid culture. In summary, SHP2 is required for induction of C/EBPα expression and granulopoiesis in response to G-CSF or other cytokines independent of SHP2-mediated ERK activation.