Establishment of a promoter-based chromatin architecture on recently replicated DNA can accommodate variable inter-nucleosome spacing
Establishment of a promoter-based chromatin architecture on recently replicated DNA can accommodate variable inter-nucleosome spacing
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DOI：
10.1093/nar/gkw331
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发表时间：
2016-09-06
影响因子：
14.9
通讯作者：
Owen-Hughes, Tom
中科院分区：
文献类型：
--
作者：
Fennessy, Ross T.;Owen-Hughes, Tom
核小体是真核生物染色质的基本亚基，根据转录起始点进行组织。这种组织的持久性面临的一个主要挑战是DNA复制过程中核小体的解体。在这里，我们使用互补的方法来定位最近复制的DNA上的核小体的位置。我们发现，在DNA复制后的几分钟内，核小体与启动子基本上重排。因此，在新复制的染色体被分割成子细胞之前，核小体的格局在很大程度上得到了重建，并可以作为重建基因表达计划的平台。当组蛋白的供应因伴侣蛋白CAF1的突变而中断时，一个基于启动子的结构被产生，但伴随着核小体间距的增加。这表明负责分隔核小体的染色质重塑酶能够组织具有一系列不同连接DNA长度的核小体。
Nucleosomes, the fundamental subunits of eukaryotic chromatin, are organized with respect to transcriptional start sites. A major challenge to the persistence of this organization is the disassembly of nucleosomes during DNA replication. Here, we use complimentary approaches to map the locations of nucleosomes on recently replicated DNA. We find that nucleosomes are substantially realigned with promoters during the minutes following DNA replication. As a result, the nucleosomal landscape is largely re-established before newly replicated chromosomes are partitioned into daughter cells and can serve as a platform for the re-establishment of gene expression programmes. When the supply of histones is disrupted through mutation of the chaperone Caf1, a promoter-based architecture is generated, but with increased inter-nucleosomal spacing. This indicates that the chromatin remodelling enzymes responsible for spacing nucleosomes are capable of organizing nucleosomes with a range of different linker DNA lengths.