染色EMT:可视化3D染色体结构和化细胞
Horng D Ou1, Sébastien Phan2, Thomas J Deerinck2
1Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
概括
这项研究使用ChromEM断层扫描揭示了染色质的三维结构,
科学领域:
- 分子生物学
- 细胞生物学
- 生物物理
背景情况:
- 基于体外和电子显微镜 (EM) 研究的染色体结构层次模型提出了DNA核体聚合物的层次折叠成更大的纤维和线粒染色体.
- 在原始状态 (in situ) 中可视化色素是具有挑战性的,限制了对其三维 (3D) 组织的理解.
研究的目的:
- 在现场可视化染色体聚合物,大基域和线性染色体的超结构和3D组织.
- 挑战和完善现有的染色体折叠和紧缩模型.
主要方法:
- 开发一种新的光染料,可染色DNA并增强EM的对比度.
- 应用ChromEM断层扫描 (ChromEMT) 进行细胞内的高分辨率3D成像.
主要成果:
- 染色体存在于一个无序的,直径为5至24纳米的曲线链.
- 这一链中包含了不同3D度分布,
- 染色质链表现出不同的粒子排列和结构紧缩的曲模式.
结论:
- 已建立的染色体折叠等级模型很可能是一种过度简单化.
- 通过无序链包装机制实现染色质紧缩,适应不同的细胞状态.
- 提供了前所未有的洞察力.
相关概念视频
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Euchromatin is the less dense region of the chromatin and stains lighter. Euchromatin contains histone H3 extensively...
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In combination with specialized DNA binding protein called Histones, the DNA double helix forms a compact DNA: protein complex called chromatin. The chromatin itself is further compacted into higher-order...
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