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arXiv 0705.1656q-bio.GN
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染色质折叠与人类基因组功能

Chromatin Folding in Relation to Human Genome Function

Julio Mateos-Langerak, Osdilly Giromus, Wim de Leeuw, Manfred Bohn, Pernette J. Verschure, Gregor Kreth, Dieter W. Heermann, Roel van Driel, Sandra Goetze

摘要:

三维染色质结构与基因组功能密切相关,特别是转录。然而,染色质纤维在间期核中的折叠路径是未知的。在这里,我们系统地测量了3D物理距离成对标记的基因组位置之间的基因密集,高度转录的域和基因穷人的不太活跃的地区在染色体1和11的G1细胞核的人原代成纤维细胞,使用荧光原位杂交。我们的研究结果和其他人发表的那些基于聚合物物理学的解释表明,染色质纤维的折叠可以被描述为球状状态(GS)的聚合物,通过聚合物内的吸引力相互作用来抵消自我回避力。GS聚合物模型能够描述染色质折叠以及高表达的结构域和低表达的结构域,表明它们在Kuhn长度和染色质压实方面不同。每种类型的基因组结构域构成相对紧凑的球状折叠状态的集合,导致在其他方面相同的细胞之间的相当大的细胞间变异。我们提出的证据不同的聚合物折叠制度的染色质纤维的长度尺度上的几个兆碱基对和完整的染色体臂(几十Mb)。我们的研究结果提出了一个新的观点,染色质纤维的折叠在间期和开放的可能性,以探索染色质纤维内的相互作用的性质。

英文摘要:

Three-dimensional (3D) chromatin structure is closely related to genome function, in particular transcription. However, the folding path of the chromatin fiber in the interphase nucleus is unknown. Here, we systematically measured the 3D physical distance between pairwise labeled genomic positions in gene-dense, highly transcribed domains and gene-poor less active areas on chromosomes 1 and 11 in G1 nuclei of human primary fibroblasts, using fluorescence in situ hybridization. Interpretation of our results and those published by others, based on polymer physics, shows that the folding of the chromatin fiber can be described as a polymer in a globular state (GS), maintained by intra-polymer attractive interactions that counteract self-avoidance forces. The GS polymer model is able to describe chromatin folding in as well the highly expressed domains as the lowly expressed ones, indicating that they differ in Kuhn length and chromatin compaction. Each type of genomic domain constitutes an ensemble of relatively compact globular folding states, resulting in a considerable cellto- cell variation between otherwise identical cells. We present evidence for different polymer folding regimes of the chromatin fiber on the length scale of a few mega base pairs and on that of complete chromosome arms (several tens of Mb). Our results present a novel view on the folding of the chromatin fiber in interphase and open the possibility to explore the nature of the intra-chromatin fiber interactions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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