Molecular basis of asymmetric division and lineage commitment in hematopoietic stem cells

造血干细胞不对称分裂和谱系定型的分子基础

基本信息

批准号：
17209036
负责人：
NAKAUCHI Hiromitsu
金额：
$ 33.45万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17209036/
关键词：
hematopoietic stem cells asymmetric division DNA methylation self-renewal commitment DNAメチル化酵素 Dnmt3a Dnmt3b

项目摘要

Stem cells are defined as cells with multilineage differentiation and self-renewal potentials. These cells play a crucial role in the development, regeneration, and maintenance of tissues and organs. Since mouse hematopoietic stem cells (HSCs) could be highly purified, we analyzed their differentiation manner at the clonal level. Using mouse HSCs as an adult stem cell model, we attempted to clarify the molecular basis underlying self-renewal and lineage commitment in stem cells. Moreover, we sought a regulatory mechanism in common with other adult stem cells. We successfully established a sensitive single-cell reconstitution assay by using compromised bone marrow cells as rescue cells for lethally irradiated mice. Using this method, differentiation potentials in paired daughter cells should be clarified in more detail. We also successfully developed a single-cell immunostaining method to quantitatively detect intracellular molecules in HSCs. Using this method, we were able to show intracellular mobilization and phosphorylation of signal molecules. We tried to detect transcription factors, DNA transmethylases, polycomb group molecules that would be unevenly distributed between paired daughter cells. However, so far we have not found such molecules. On the other hand, we showed that either Dnmt3a or Dnmt3b is essential for self-renewal in HSCs. Interestingly, neither Dnmt3 nor Dnmt3b was shown to be necessary for multilineage differentiation in HSCs. We analyzed hepatic stem cells isolated from mouse fetal liver. Over-expression of a dominant negative form of Tcf-4 inhibited both self-renewal and differentiation/maturation in hepatic stem cells.

干细胞被定义为具有多节分化分化和自我更新电势的细胞。这些细胞在组织和器官的发育，再生和维持中起着至关重要的作用。由于可以高度纯化小鼠造血干细胞（HSC），因此我们在克隆水平上分析了它们的分化方式。使用小鼠HSC作为成年干细胞模型，我们试图阐明干细胞中的分子基础自我更新和谱系承诺。此外，我们寻求与其他成年干细胞共同的调节机制。我们通过使用受损的骨髓细胞作为致命的辐照小鼠的拯救细胞，成功地建立了一种灵敏的单细胞重建测定法。使用这种方法，应更详细地阐明配对子细胞中的分化电位。我们还成功开发了一种单细胞免疫染色方法，以定量检测HSC中的细胞内分子。使用这种方法，我们能够显示信号分子的细胞内动员和磷酸化。我们试图检测转录因子，DNA转甲基酶，多肉液组分子，这些分子将不均分布在成对的子细胞之间。但是，到目前为止，我们还没有找到这样的分子。另一方面，我们表明DNMT3A或DNMT3B对于HSC中的自我更新至关重要。有趣的是，DNMT3和DNMT3B均未证明对于HSC中的多琳分化是必需的。我们分析了从小鼠胎儿肝脏分离的肝干细胞。 TCF-4的主要负面形式的过表达抑制了肝干细胞中的自我更新和分化/成熟。

项目成果

期刊论文数量（72）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Cdkn1a deletion improves stem cell function and lifespan of mice with dysfunctional telomeres without accelerating cancer formation

DOI：
10.1038/ng1937
发表时间：
2007-01-01
期刊：
NATURE GENETICS
影响因子：
30.8
作者：
Choudhury, Aaheli Roy;Ju, Zhenyu;Rudolph, K. Lenhard
通讯作者：
Rudolph, K. Lenhard

Lnk negatively regulates self-renewal of hematopoietic stem cells by modifying thrombopoietin-mediated signal transduction

DOI：
10.1073/pnas.0606238104
发表时间：
2007-02-13
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
影响因子：
11.1
作者：
Seita, Jun;Ema, Hideo;Nakauchi, Hirornitsu
通讯作者：
Nakauchi, Hirornitsu

Endomucin, a CD34-like sialomucin, marks hematopoietic stem cells throughout development.