发育调节的Xist促进器开关介导X失活的启动
C M Johnston1, T B Nesterova, E J Formstone
1MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London, United Kingdom.
Cell
|September 30, 1998
概括
鼠标的Xist基因是Xist基因.
科学领域:
- 表观遗传学和基因调控
- 哺乳动物发展 哺乳动物发展
- 没有编码的RNAs.
背景情况:
- 在雌性哺乳动物中,X染色体失活 (XCI) 会使一个X染色体沉默.
- 在启动XCI时,Xist基因起着至关重要的作用.
- 调节XistRNA水平对于适当的XCI至关重要.
- 以前对Xist监管的理解集中在一个单一的促销商上.
研究的目的:
- 研究替代促进剂在调节XistRNA稳定性中的作用.
- 为了确定参与Xist基因转录的新型促销者.
- 了解X染色体无活化过程中XistRNA积累的机制.
主要方法:
- 使用转录基因技术分析XistRNA异型.
- 新型Xist基因促进体的识别和特征.
- 在经过X失活的细胞中对促进体活性进行实验性操纵.
- RNA稳定性测试用于区分稳定和不稳定的Xist转录.
主要成果:
- 替代促进剂的使用产生了不同的稳定和不稳定的Xist RNA异型.
- 一个新的上游推动者产生不稳定的Xist转录.
- 以前已知的促销者和一个新的下游促销者产生稳定的XistRNA.
- 促进体之间的发育调节的切换控制XistRNA稳定和积累.
结论:
- 替代促进剂的使用是XCI期间调节XistRNA稳定的关键机制.
- 一个促进器开关确保在不活跃的X染色体上积累稳定的XistRNA.
- 这种调节机制在哺乳动物发育过程中提供了对基因沉默的精确控制.
相关概念视频
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