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Live Cell Imaging of Chromosome Segregation During Mitosis
Published on: March 14, 2018
在干细胞分裂过程中,染色体特异的非随机姐妹染色体分离
Swathi Yadlapalli1, Yukiko M Yamashita
1Life Sciences Institute, Center for Stem Cell Biology, University of Michigan, Ann Arbor, Michigan 48109, USA. swathi@umich.edu
Nature
|May 7, 2013
概括
成人干细胞以不对称的方式分裂. 研究人员发现,在果中,X和Y染色体,但不是其他染色体,在这种分裂过程中非随机分离,这一过程需要特定的蛋白质,并可能由父母进行初始化.
科学领域:
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
- 细胞生物学 细胞生物学
背景情况:
- 成人干细胞表现出不对称的细胞分裂,用于自我更新和组织再生.
- 假设在不对称的分裂中存在非随机姐妹染色体分离的潜力,但缺乏直接证据和机制理解.
研究的目的:
- 研究非随机姐妹染色体分离在不对称地分裂的干细胞中的机制和目的.
- 为了确定参与非随机姐妹染色体分离的因素.
- 探索非随机分离在干细胞功能和分化中的影响.
主要方法:
- 开发一种高分辨率的CO-FISH (染色体导向光 in situ杂交) 技术.
- 在非对称分裂期间,对Drosophila的雄性生殖系干细胞中的姐妹染色体分离的分析.
- 基因操纵以评估中心体,SUN-KASH蛋白和Dnmt2在分离中的作用.
主要成果:
- 在Drosophila雄性生殖系干细胞中,证明了X和Y染色体姐妹染色体的非随机分离,但不是自体.
- 鉴定了中心体,SUN-KASH核包膜蛋白和Dnmt2作为非随机姐妹染色体分离的关键.
- 在生殖系干细胞过度增殖和脱差的条件下观察到随机分离.
结论:
- 提供了第一个在不对称干细胞分裂中非随机姐妹染色体分离的直接证据.
- 表明,允许非随机分离的信息是在父母游戏生成过程中建立的.
- 建议非随机分离可以确保将不同的染色体信息传递给子细胞.
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