High resolution analysis of interphase chromosome domains.
High resolution analysis of interphase chromosome domains.
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DOI：
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发表时间：
2000-07
影响因子：
4
通讯作者：
A. Visser;F. Jaunin;S. Fakan;J. Aten
中科院分区：
文献类型：
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作者：
A. Visser;F. Jaunin;S. Fakan;J. Aten
在探索间期染色体组织的功能方面之前，需要以高分辨率明确定义染色体区域。为了通过电子显微镜 (EM) 观察染色体，中国仓鼠成纤维细胞的 DNA 在体内用胸苷类似物 BrdU 进行标记。然后在几个细胞周期中分离标记的染色体以获得仅包含2至3条标记染色体的细胞核。随后对 BrdU 进行免疫细胞化学检测，从而可以通过电镜对保存完好的细胞核中的染色体区域和染色体亚结构域进行分析。我们的结果首次提供了间期细胞核中染色体的高分辨率可视化。我们表明，染色体结构域要么通过染色质间空间彼此分开，要么紧密接触，其 DNA 没有或很少混合。这表明，虽然染色体形成离散的区域，但相邻染色体的染色质可能在有限的区域内接触，从而暗示染色体-染色体相互作用。染色体被组织为凝聚的染色质，分散的染色质延伸到基本上没有 DNA 的染色质间空间。已知染色质间空间参与各种核功能，形成穿过和围绕染色体区域的互连通道。讨论了该组织的功能含义。
Chromosome territories need to be well defined at high resolution before functional aspects of chromosome organization in interphase can be explored. To visualize chromosomes by electron microscopy (EM), the DNA of Chinese hamster fibroblasts was labeled in vivo with thymidine analogue BrdU. Labeled chromosomes were then segregated during several cell cycles to obtain nuclei containing only 2 to 3 labeled chromosomes. Subsequent immunocytochemical detection of BrdU allowed analysis by EM of chromosome territories and subchromosomal domains in well preserved nuclei. Our results provide the first high resolution visualization of chromosomes in interphase nuclei. We show that chromosome domains are either separated from one another by interchromatin space or are in close contact with no or little intermingling of their DNA. This demonstrates that, while chromosomes form discrete territories, chromatin of adjacent chromosomes may be in contact in limited regions, thus implying chromosome-chromosome interactions. Chromosomes are organized as condensed chromatin with dispersed chromatin extending into the interchromatin space that is largely devoid of DNA. The interchromatin space, which is known to be involved in various nuclear functions, forms interconnecting channels running through and around chromosome territories. Functional implications of this organization are discussed.