在小鼠发育过程中Xist的表达表明它在启动X染色体不活化过程中发挥了作用
1Section of Comparative Biology, Medical Research Council Clinical Research Centre, Harrow, England.
Cell
|January 29, 1993
概括
小鼠Xist基因启动X染色体的非激活,先于过程本身. 它在早期发育中的印记表达表明Xist会导致父系X的无活化,Xce基因基因调节这种效应.
科学领域:
- 遗传学 遗传学是一种遗传学.
- 发展生物学 发展生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- Xist基因位于X无活化中心 (Xic),并从无活性的X染色体表达出来.
- 基因Xist是控制X染色体失活 (XCI) 的候选基因.
研究的目的:
- 研究小鼠发育过程中Xist基因表达和X染色体失活之间的时间关系.
- 要确定Xist表达是否是XCI的原因或后果.
主要方法:
- 分析Xist基因表达时间在小鼠Morulae和胚胎囊.
- 对Xist等位基因特异性表达和印记模式的研究.
- 检查Xce (X控制元素) 基因对Xist表达和XCI的影响.
主要成果:
- 基因组表达在X染色体不活化之前开始,这表明它起到了起因作用.
- 早期的Xist表达被印记,有利于父方的等位基因,这可能导致父方X在 trofhectoderm 中不活化.
- 强大的Xce等位基因可以减轻印记Xist表达在 trofhectoderm的影响.
- 在胃化之前,Xist印记会消失,这与随机X无活化相吻合.
结论:
- 晶在启动X染色体不活化方面发挥着直接作用.
- 印制的Xist表达可能是早期发育中非随机的父性X失活的原因.
- 通过影响印制的Xist表达,Xce基因基因调节XCI的过程.
相关概念视频
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