相关实验视频
Updated: Jun 28, 2026

11:15
Pooled shRNA Screen for Reactivation of MeCP2 on the Inactive X Chromosome
Published on: March 2, 2018
聚组蛋白是小鼠X染色体短重复RNA所准的
Jing Zhao1, Bryan K Sun, Jennifer A Erwin
1Howard Hughes Medical Institute, Boston, MA 02115, USA.
概括
雌性哺乳动物通过X染色体失活 (XCI) 沉默一个X染色体. 一个新的ncRNA,RepA,在XistRNA中招募PRC2,一个关键复合体,启动XCI和基因沉默.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 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:
- 哺乳动物雌性通过使一个X染色体不活化来使X染色体剂量均等.
- X染色体失活 (XCI) 的启动依赖于Xist非编码RNA (ncRNA) 在cis中积累.
- 由于未确定的相互作用因素,Xist介导的基因沉默的确切机制尚不清楚.
研究的目的:
- 为了阐明Xist诱导的基因沉默的机制.
- 为了确定在X染色体失活期间与Xist相互作用的因素.
- 研究ncRNAs在招募沉默复合体中的作用.
主要方法:
- 在XistRNA中发现和描述一个1.6千基的ncRNA (RepA).
- 识别了多镇压复合体2 (PRC2) 作为RepA的直接目标.
- 评估RepA枯竭和PRC2缺乏对Xist表达和基因素修饰的影响.
主要成果:
- RepA被确定为Xist中的ncRNA,与PRC2.2直接相互作用.
- Ezh2被确定为PRC2的子单元,它与RepARNA结合.
- 发现Antisense Tsix RNA可以抑制RepA-PRC2相互作用.
- RepA耗尽取消了全长的Xist诱导和H3K27三甲基化.
- 由于PRC2的缺陷,Xist上调受损,这证实了其对XCI启动的需求.
结论:
- RepARNA作为一个关键的辅助因子,招募PRC2启动X染色体不活化.
- RepA-PRC2相互作用对于XCI的发病和传播至关重要.
- 这项研究揭示了一个新的机制,即ncRNAs招募Polycomb复合体以准表观遗传沉默的位置.
更多相关视频
08:27A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome
Published on: May 22, 2019
15:54Combined DNA-RNA Fluorescent In situ Hybridization (FISH) to Study X Chromosome Inactivation in Differentiated Female Mouse Embryonic Stem Cells
Published on: June 14, 2014
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