在活细胞中,MINFLUX 剖析核细胞和压缩色素结构
Hong Xie1,2, Yi Hu1,2, Ruixi Cheng1,2
1School of Artificial Intelligence Science and Technology, University of Shanghai for Science and Technology, Shanghai 2000093, China.
National science review
|February 9, 2026
概括
用先进的显微镜在活细胞中可视化了对基因组紧缩至关重要的染色质纤维. 这些大约30纳米宽的结构存在于富含AT的DNA区域中,并揭示了核超结构.
科学领域:
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
- 生物物理学的生物物理.
背景情况:
- 染色体结构是基因组组织和基因调节的关键.
- 实验室模型表明,11纳米核聚合物形成30纳米纤维,但现场证据缺乏.
- 现有的细胞研究报告了无序的链条或类似液体的域,质疑凝结纤维的存在.
研究的目的:
- 研究活细胞中原生染色素纤维的现场存在和结构.
- 以高分辨率和低光毒性可视化色素超结构.
主要方法:
- 开发一种闪的光染料,用于AT丰富的DNA可视化.
- 三维 (3D) MINFLUX定位显微镜用于高速,低光毒性成像的应用.
- 观测染色体纤维组合,基因素同定位和核细胞折叠.
主要成果:
- 原生色素纤维的可视化 (大约. 30nm) 在活细胞核中,与基因素同定位.
- 纤维的宽度可变,主要位于核内部.
- 大多数观察到的纤维在Trichostatin A治疗后被拆解,这表明有动态调节.
- 3D MINFLUX揭示了个体核细胞的超结构,其中5-10个探针包裹着一个11纳米圆柱体.
结论:
- 原生染色素纤维 (大约. 30nm) 确实存在于活细胞中,特别是在富含AT的基因组区域.
- MINFLUX纳米镜对原生染色质超结构和折叠提供了前所未有的洞察力.
- 这项研究解决了有关染色体纤维存在的争论,并为研究基因组紧缩提供了新的工具.
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