Molecular mechanisms regulating the growth and differentiation of hematopoietic stem cells

调节造血干细胞生长和分化的分子机制

• 批准号: 12470200
• 负责人: KANAKURA Yuzuru
• 金额: $ 8.83万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12470200/
• 关键词: ras; proliferation; differentiation; signal transduction; STAT; transcription factor; megakaryocyte; AIM-1

(1) Stem cell factor (SCF) has crucial roles in proliferation, survival and differentiation of hematopoietic stem cells through binding to c-Kit receptor (KIT). We made a series of 22 KIT mutants, in which Tyr (Y) residue was substituted to Phe (F) in the cytoplasmic domain, and introduced into BAF3 cells. On stimulation with SCF, BAF3 expressing KIT^<WT>(WT) showed cell migration and Ca^<2+> mobilization. Among 22YF mutants, Y567F and Y719F showed significantly reduced cell migration and Ca^<2+> mobilization. Analysis on signaling cascades suggested that Y567-mediated Src family kinase (SFK) activation led to Ca^<2+> influx and migration, and that P38MAPkinase (P38MAPK) and Erk1/2 were also regulated by Y567/SFK and involved in cell migration. Also, Y719-mediated PI3K pathway was suggested to be involved in the migration. These results indicate that two major KIT signaling pathways lead to cell migration, one is Y567-SFK-p38MAPK-Erk and another is Y719-PI3 kinase.(2) Thrombopoietin (T … More PO) and its receptor c-mpl play crucial roles in growth and megakaryocytic differentiation of hematopoietic stem cells. We found that Ras activation was involved in thrombopoietin (TPO)-induced megakaryocytic differentiation. Furthermore, we demonstrated that GATA-1 activities was required for the Ras-mediated megakaryocytic differentiation, and that GATA-1 activities were regulated negatively by the direct interaction with other lineage-specific transcription factors, PU.1 and c-Myb.(3) AIM-1 belongs to an Aurora/Ipl1 serine threonine kinase family, and is supposed to play key roles in mitosis. In human hematopoietic cells, expression of AIM-1 was restrictedly observed at G2/M phase of cell cycle. In contrast, AIM-1 was continuously repressed during megakaryocytic polyploidization. Supplement of AIM-1 activities by the induced expression of wild-type AIM-1 canceled TPA-induced polyploidization of K562 cells, and the suppression of AIM-1 activities by dominant-negative AIM-1 led to polyploidization. These results suggested that down-regulation of AIM-1 at M phase may be involved in abortive mitosis and polyploid formation of megakaryocytes. Less

(1)干细胞因子（Stem cell factor，SCF）通过与c-Kit受体（c-Kit receptor，KIT）结合，在造血干细胞的增殖、存活和分化中发挥重要作用。我们制备了一系列22个KIT突变体，其中Tyr（Y）残基被胞质结构域中的Phe（F）取代，并将其导入BAF 3细胞。在SCF刺激下，表达KIT^<WT>（WT）的BAF 3细胞表现出细胞迁移和Ca^2+动员。在22个YF突变体中，Y 567 F和Y 719 F表现出显著降低的细胞迁移和Ca^2+动员。信号级联分析表明，Y 567/SFK激活Src家族激酶（SFK）导致Ca^2+内流和细胞迁移，P38 MAPK和Erk 1/2也受Y 567/SFK的调节，并参与细胞迁移。此外，Y 719介导的PI 3 K途径被认为参与了迁移。这些结果表明，两个主要的KIT信号通路导致细胞迁移，一个是Y 567-SFK-p38 MAPK-Erk，另一个是Y 719-PI 3激酶。(2)血小板生成素（T ...更多信息 PO）及其受体c-mpl在造血干细胞的生长和向巨核细胞分化中起重要作用。我们发现Ras活化参与血小板生成素（TPO）诱导的巨核细胞分化。此外，我们证明了加塔-1活性是Ras介导的巨核细胞分化所必需的，并且加塔-1活性通过与其他谱系特异性转录因子PU.1和c-Myb的直接相互作用而受到负调控。(3)AIM-1属于Aurora/Ipl 1丝氨酸苏氨酸激酶家族，被认为在有丝分裂中起关键作用。在人造血细胞中，观察到AIM-1的表达局限于细胞周期的G2/M期。相反，AIM-1在巨核细胞多倍化过程中被持续抑制。通过诱导野生型AIM-1的表达来补充AIM-1的活性，取消了TPA诱导的K562细胞的多倍化，并且通过显性负性AIM-1抑制AIM-1的活性导致多倍化。这些结果提示，M期AIM-1的下调可能参与了巨核细胞有丝分裂的失败和多倍体的形成。少

项目成果

Kawasaki, A., Matsumura, I., Miyagawa, J., Ezoe, S., Tanaka, H., Terada, Y., Tatsuka, M., Machii, T., Miyazaki, H., Furukawa, Y., and Kanakura, Y.: "Down-regulation of and AIM-1 kinase couples with megakaryocytic polyploidization of human hematopoietic ce

川崎，A.，松村，I.，宫川，​​J.，Ezoe，S.，田中，H.，寺田，Y.，龙香，M.，町井，T.，宫崎，H.，古川，Y.，

Nishimura, J-I., Philips, K.L., Ware, R.E., Hall, S., Wilson, L., Gentry, T.L., Howard, T.A.., Murakami, Y., Shibano, M., Machii, T., Gilboa, E., Kanakura, Y., Takeda, J., Kinoshita, T., Rosse, W.F., and Smith, C.A.: "Efficient retrovirus-mediated PIG-A g

Nishimura, J-I.、Philips, K.L.、Ware, R.E.、Hall, S.、Wilson, L.、Gentry, T.L.、Howard, T.A.、Murakami, Y.、Shibano, M.、Machii, T.、Gilboa, E

Ueda, S., et al.: "Critical roles of c-kit tyrosine residues 567 and 719 in stem cell factor-induced chemotaxis"Blood. (in press).

Ueda, S., et al.：“c-kit 酪氨酸残基 567 和 719 在干细胞因子诱导的趋化性中的关键作用”血液。

Sonoyama, J., et al.: "Functional cooperation among Ras, STAT5, and P13-K is required for full oncogenic activitics of BCR/ABL in K562 cells"J. Biol. Chem.. (in press).

Sonoyama, J. 等人：“K562 细胞中 BCR/ABL 的完全致癌活性需要 Ras、STAT5 和 P13-K 之间的功能合作”。

Matsumura, I., Hashimoto, K, Ikeda, H., Odajima, J., Tanaka, H., Kato, T, Miyazaki, H., and Kanakura, Y.: "Increased D-type cyclin expression together with decreased cdc2 activity confers megakaryocytic differentiation of a human thrombopoietin-dependent

Matsumura, I.、Hashimoto, K、Ikeda, H.、Odajima, J.、Tanaka, H.、Kato, T、Miyazaki, H. 和 Kanakura, Y.：“D 型细胞周期蛋白表达增加，同时 cdc2 减少