在活跃的X染色体上基因体特异甲基化
1Center for Human Genetic Research and Department of Medicine, Massachusetts General Hospital, Harvard Medical School, 185 Cambridge Street, Boston, MA 02114, USA. hellman@chgr.mgh.harvard.edu
Science (New York, N.Y.)
|February 27, 2007
概括
活跃的X染色体 (Xa) 在基因体中显示出显著更多的DNA甲基化,而非活跃的X染色体 (Xi). 这种差异性甲基化模式表明一种双重程序影响了基因表达潜力.
科学领域:
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 不同的DNA甲基化对于表观遗传基因调节至关重要.
- 已知非活跃X染色体 (Xi) 上的促进体CpG岛屿的等位基因特异性甲基化.
- 活跃的X (Xa) 和非活跃的X (Xi) 染色体上的整体甲基化模式在很大程度上仍未被描述.
研究的目的:
- 为了研究人类活跃和非活跃X染色体的全球甲基化模式.
- 为了确定X染色体中异位基因特异甲基化的分布和特征.
主要方法:
- 在人类X染色体上的1000多个信息位点进行了异位基因特异性分析.
- 在活性X (Xa) 和非活性X (Xi) 染色体之间比较甲基化模式.
主要成果:
- 活跃的X染色体 (Xa) 与非活跃的X染色体 (Xi) 相比,表现出两倍以上的等位基因特异性甲基化.
- 这种甲基化主要位于基因体内,影响许多相邻的CpG.
- 在X无活化之前,这些基因体甲基化部位被双基甲基化.
结论:
- 一个双方甲基化-脱甲基化程序建立了XA特异性低甲基化在促进体和基因体内的高甲基化.
- 这些发现表明,全球DNA甲基化模式与X染色体上的基因表达潜力之间存在联系.
相关概念视频
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01:37Epigenetic Regulation
Epigenetic changes alter the physical structure of the DNA without changing the genetic sequence and often regulate whether genes are turned on or off. This regulation ensures that each cell produces only proteins necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
X-chromosome...
X-chromosome...
01:46Epigenetic Regulation
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02:38Heterochromatin
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01:01Euchromatin
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