Fundamental molecular mechanisms of stem cell system

干细胞系统的基本分子机制

基本信息

批准号：
10470059
负责人：
NAKANO Toru
金额：
$ 8万
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：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10470059/
关键词：
hematopoietic stem cells embryogenesis cell differentiaition stem cell system primordial germ cell embryonic stem cell

项目摘要

In order to investigate the fundamental molecular mechanisms of stem cell systems, two kinds of stem cells were analyzed. One is totipotent mouse embryonic stem cells (ES cells) and the other is germ line stem cells, namely, primordial germ cells (PGC).Myb family genes are known to posess essential roles in cell differentiation. We utilized a conditinal dominant negative Myb (MERT), which represses the function of all members of Myb (c-, A- and B-Myb). ES cells express B-Myb almost exclusively among Myb family members. Thus, the activation of MERT brings about the suppression of B-Myb function. Unfortunately, the suppression of B-Myb function does not alter differentiation status of ES cells. In stead, cell cycle and cell adhesion are affected. The alteration of cell cycle is reasonable from previous reports and expression pattern of B-Myb. However, the alteration of cell adhesion is a new finding. Precise examination revealed that the change of surface expression of cadherin and integrin was initiated by the inhibition of B-Myb. Considering that the transcription level of these two adhesion molecules was not changed, it is probable that some post-transcriptional modification was caused by the inhibition of B-Myb. Together with the data of B-Myb knock our mice, B-Myb is essential for cell adhesion at the early embryogenesis.TNAP (tissue non-specific alkaline phosphatase)-EGFP knock in mouse was produced and used for isolating PGCs from mouse developing embryos. Gene expression in ES cells and PGCs was analyzed by SAGE analysis. About 10,000 expression tags were sequenced from both sources. A couple of the family genes were preferentially expressed in either ES cells or PGCs. And one novel gene expressed in ES cells and PGCs was cloned.

为了研究干细胞系统的基本分子机制，分析了两种干细胞。一种是小鼠胚胎干细胞（ES细胞），另一个是生殖系干细胞，即原始生殖细胞（PGC）。Myb家族基因在细胞分化中起着基本作用。我们利用了一个孔的主导MYB（MERT），该MYB（MERT）抑制了MYB所有成员（C-，A-和B-MYB）的功能。 ES细胞在MYB家庭成员中几乎完全表达B-MYB。因此，MERT的激活带来了B-MYB功能的抑制。不幸的是，B-MYB功能的抑制不会改变ES细胞的分化状态。在稳定的情况下，细胞周期和细胞粘附受到影响。从先前的报告和B-MYB的表达模式中，细胞周期的改变是合理的。但是，细胞粘附的改变是一个新发现。精确的检查表明，钙粘蛋白和整联蛋白的表面表达的变化是通过抑制B-MYB引发的。考虑到这两个粘附分子的转录水平没有改变，很可能是由B-MYB抑制引起的一些转录后修饰。与B-Myb敲击我们的小鼠的数据一起，B-Myb对于早期胚胎发生时细胞粘附至关重要。TNAP（组织非特异性碱性磷酸酶）-EGFP在小鼠中产生，并用于从发育胚胎中分离出PGC。。通过SAGE分析分析ES细胞和PGC中的基因表达。从两个来源测序了约10,000个表达式标签。在ES细胞或PGC中优先表达了几个家族基因。并克隆了在ES细胞和PGC中表达的一种新型基因。