通过DNA模板链序列识别姐妹染色体
Ester Falconer1, Elizabeth A Chavez, Alexander Henderson
1Terry Fox Laboratory, B.C. Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada.
Nature
|December 18, 2009
概括
曾经被认为是相同的姐妹染色体现在可以通过使用CO-FISH的DNA模板链来区分. 这揭示了一些结肠细胞的非随机分离,影响了细胞在发育过程中的命运.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 发展生物学 发展生物学
背景情况:
- 姐妹染色体通常被认为是相同的,并随机分离.
- 有证据表明,在更简单的生物体中,有功能差异和非随机分离.
- 这对多细胞发育中的细胞命运调节有影响.
研究的目的:
- 测试假设分化姐妹染色体和非随机分离调节多细胞生物中的细胞命运.
- 开发一种可靠地区分姐妹染色体的方法.
主要方法:
- 使用单向探针利用染色体定向光在位杂交 (CO-FISH).
- 在小鼠元相染色体中确定了父母DNA模板链 (沃森和克里克).
- 在各种类型的小鼠细胞中分析了线粒细胞分离模式.
主要成果:
- 在小鼠染色体中建立了重复性DNA (中粒和端粒重复) 的统一方向.
- 根据DNA模板链的方向,证明了姐妹染色体的差异标记.
- 在纤维细胞和胚胎干细胞中观察到随机的姐妹染色体分离.
- 在结肠密室上皮细胞的一个子集中发现了显著的非随机的姐妹染色体分离.
结论:
- DNA模板链序列可以可靠地区分姐妹染色体.
- 非随机的姐妹染色体分离发生在体内特定的细胞类型中,扩展到已知的干细胞之外.
- 这一发现支持了差异化姐妹染色体和非随机分离在发育过程中决定细胞命运的假设.
相关概念视频
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At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
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