多能因子Oct4与Ctcf相互作用,并控制X染色体对配和计数
Mary E Donohoe1, Susana S Silva, Stefan F Pinter
1Howard Hughes Medical Institute, USA.
Nature
|June 19, 2009
概括
一个关键的多能性因子Oct4通过调节同类染色体配对和计数来启动X染色体失活 (XCI). 这一发现揭示了Oct4
科学领域:
- 表观遗传学和基因调控
- 干细胞生物学 干细胞生物学
- 基因组学和染色体生物学
背景情况:
- 胚胎干细胞 (ES) 的多能性是由转录因子控制的.
- 在基因剂量差异化过程中,X染色体失活 (XCI) 会使一个雌性X染色体沉默.
- XCI涉及同源染色体配对,计数和随机选择,与细胞分化密切相关.
研究的目的:
- 阐明多能性因子和X染色体失活 (XCI) 之间的相互联系.
- 确定Oct4在调节XCI中的作用.
- 了解Oct4如何影响X染色体对配和计数.
主要方法:
- 研究了Oct4在X失活中心与调控性非编码RNA基因 (Tsix和Xite) 的结合.
- 检查了Oct4和XCI转化因子 (Ctcf和Yy1) 之间的蛋白质-蛋白质相互作用.
- 评估了Oct4枯竭对雌性细胞同源X染色体配对和XCI的影响.
主要成果:
- Oct4直接与XCI的关键监管者Tix和Xite结合.
- Oct4与Ctcf和Yy1形成复合体,这对XCI至关重要.
- Oct4 枯竭取消同源的 X 染色体配对,并导致双 X 染色体不活化.
结论:
- Oct4被确定为XCI层次结构顶部的主调节器.
- Oct4触发同源的X染色体配对和计数,对于适当的XCI至关重要.
- 这项研究赋予Oct4在X染色体重编程和表观遗传调节中的新功能.
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