Chromatin Constrains the Initiation and Elongation of DNA Replication.
Chromatin Constrains the Initiation and Elongation of DNA Replication.
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染色质约束DNA复制的启动和伸长。
DOI：
10.1016/j.molcel.2016.10.035
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发表时间：
2017-01-05
期刊：
影响因子：
16
通讯作者：
Remus D
中科院分区：
文献类型：
--
作者：
Devbhandari S;Jiang J;Kumar C;Whitehouse I;Remus D
真核细胞的染色体DNA在一系列复杂的细胞周期调控事件中被忠实地复制，这些事件还没有完全被理解。在这里，我们报道了用发芽酵母中纯化的蛋白质在溶液中重组DNA无复制。该系统概括了受调控的双向起始激活；由三个复制的DNA聚合酶POLα、POLδ和POLε合成领先和滞后链；以及冈崎片段的规范成熟成连续的子链。我们揭示了染色质在DNA复制过程中的双重调节作用：促进来源依赖和通过限制POLδ进程来确定冈崎片段长度。该系统为真核细胞染色体复制的详细机制分析提供了一个功能平台。Devbhandari等人。报道了用纯化的蛋白质重组真核DNA复制。该系统概括了双向起始点激发和调控的领先和滞后链合成，揭示了染色质在限制Okazaki片段长度和起始点选择方面的关键作用。
Eukaryotic chromosomal DNA is faithfully replicated in a complex series of cell-cycle-regulated events that are incompletely understood. Here we report the reconstitution of DNA replication free in solution with purified proteins from the budding yeast Saccharomyces cerevisiae. The system recapitulates regulated bidirectional origin activation; synthesis of leading and lagging strands by the three replicative DNA polymerases Pol α, Pol δ, and Pol ε; and canonical maturation of Okazaki fragments into continuous daughter strands. We uncover a dual regulatory role for chromatin during DNA replication: promoting origin dependence and determining Okazaki fragment length by restricting Pol δ progression. This system thus provides a functional platform for the detailed mechanistic analysis of eukaryotic chromosome replication. Devbhandari et al. report the reconstitution of eukaryotic DNA replication with purified proteins. The system recapitulates bidirectional origin firing and regulated leading and lagging strand synthesis, uncovering critical roles for chromatin in constraining Okazaki fragment length and origin site selection.