Nucleosome architecture throughout the cell cycle.
Nucleosome architecture throughout the cell cycle.
复制标题
DOI：
10.1038/srep19729
复制
发表时间：
2016-01-28
影响因子：
4.6
通讯作者：
Orozco M
中科院分区：
文献类型：
--
作者：
Deniz Ö;Flores O;Aldea M;Soler-López M;Orozco M
核小体通过介导蛋白质进入DNA，为转录和DNA复制提供额外的调节机制。在细胞周期中，染色质经历了几次构象变化，然而这些变化对细胞过程的功能意义在很大程度上是未知的。在这里，我们提出了第一个全面的全基因组研究核小体可塑性在单碱基对分辨率沿着细胞周期在酿酒酵母。我们确定了核小体的组织，特别关注两个调控区域：转录起始位点（TSS）和复制起点（ORI）。在细胞周期中，TSS周围的核小体以循环方式显示重排。与间隙（G1和G2）期相反，核小体在S和M期具有更模糊的组织。此外，核小体重排的编排与细胞周期期间基因表达的变化相关，表明核小体与细胞周期之间存在密切联系依赖性基因功能。另一方面，核小体在细胞周期中沿着ORI周围更具动态性，尽管在早期发射起点中具有更严格的调节，这意味着核小体在复制起点上的功能作用。我们的研究提供了一个动态的图片核小体组织在整个细胞周期，并强调了随后的影响转录和复制活动。
Nucleosomes provide additional regulatory mechanisms to transcription and DNA replication by mediating the access of proteins to DNA. During the cell cycle chromatin undergoes several conformational changes, however the functional significance of these changes to cellular processes are largely unexplored. Here, we present the first comprehensive genome-wide study of nucleosome plasticity at single base-pair resolution along the cell cycle in Saccharomyces cerevisiae. We determined nucleosome organization with a specific focus on two regulatory regions: transcription start sites (TSSs) and replication origins (ORIs). During the cell cycle, nucleosomes around TSSs display rearrangements in a cyclic manner. In contrast to gap (G1 and G2) phases, nucleosomes have a fuzzier organization during S and M phases, Moreover, the choreography of nucleosome rearrangements correlate with changes in gene expression during the cell cycle, indicating a strong association between nucleosomes and cell cycle-dependent gene functionality. On the other hand, nucleosomes are more dynamic around ORIs along the cell cycle, albeit with tighter regulation in early firing origins, implying the functional role of nucleosomes on replication origins. Our study provides a dynamic picture of nucleosome organization throughout the cell cycle and highlights the subsequent impact on transcription and replication activity.