哺乳动物基因组的拓领域通过对染色质相互作用的分析来确定
Jesse R Dixon1, Siddarth Selvaraj, Feng Yue
1Ludwig Institute for Cancer Research, 9500 Gilman Drive, La Jolla, California 92093, USA.
Nature
|April 13, 2012
概括
研究人员发现了大型,稳定的.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 基因组的空间组织对其功能至关重要,但更高阶的基因组结构仍然不太了解.
- 现有的模型对染色质结构和基因组功能之间的关系提供了有限的机械洞察力.
- 基因组技术的进步,如Hi-C,使得更高阶染色体相互作用的全基因组分析成为可能.
研究的目的:
- 以高分辨率研究人类和小鼠胚胎干细胞和分化细胞中的3D基因组组织.
- 识别和描述基因组组织的新型结构特征.
- 探索这些结构特征的功能和进化影响.
主要方法:
- 利用Hi-C技术,以史无前例的分辨率绘制全基因组的染色质相互作用.
- 在人类和小鼠胚胎干细胞和终端分化的细胞类型中分析了三维基因组组织.
- 与基因组元素和功能约束相关联的识别结构特征.
主要成果:
- 确定了大型,大数据库大小的"拓领域",作为基因组组织的基本特征.
- 证明了拓学域限制了异性染色素的传播.
- 发现拓领域在细胞类型之间是稳定的,在物种之间是保存的.
- 在拓域边界观察到CTCF,家政基因,tRNA和SINE的丰富.
结论:
- 拓领域代表了哺乳动物基因组的固有结构性质.
- 这些域在调节异色素蛋白的传播和基因组功能方面发挥着作用.
- CTCF,家政基因,tRNA和SINEs可能参与建立拓域架构.
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