The Initial Response of a Eukaryotic Replisome to DNA Damage.
The Initial Response of a Eukaryotic Replisome to DNA Damage.
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DOI：
10.1016/j.molcel.2018.04.022
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发表时间：
2018-06-21
期刊：
影响因子：
16
通讯作者：
Yeeles JTP
中科院分区：
文献类型：
--
作者：
Taylor MRG;Yeeles JTP
复制体必须克服DNA损伤以确保完整的染色体复制。在这里，我们描述了最早的事件，在这个过程中，通过重组真核复制体之间的碰撞，与纯化的蛋白质组装，和DNA损伤。滞后链损伤被毫不延迟地绕过，留下子链间隙，其大小大致为冈崎片段。相反，前导链聚合酶停滞显著影响复制叉进展。我们揭示了核心复制体本身可以通过重新引发合成来绕过前导链损伤。令人惊讶的是，这种重新启动活动是罕见的，主要是由于低效的前导链重新引发，而不是单链DNA暴露或引物延伸。我们发现了几个意想不到的机制之间的领先和滞后链引发，我们建议控制复制体的DNA损伤的初始反应的区别。值得注意的是，前导链的重新启动是特别刺激RPA耗竭，这可能发生在复制应激的条件下。我们的研究结果有影响的途径选择停滞叉和启动在DNA复制起点。真核复制体和DNA损伤之间碰撞的重建前导链损伤特异性地引起叉停滞和解偶联真核复制体可以重新启动DNA损伤下游的前导链前导链和滞后链引发之间存在多种机制差异为了研究复制期间DNA聚合酶停滞后的最早事件，Taylor和Yeeles重建了用纯化蛋白质组装的酵母复制体与模板DNA损伤之间的碰撞。令人惊讶的是，重新启动的前导链的合成超出损坏是低效的，但促进RPA耗尽，而滞后链引发发生后，损坏强劲。
The replisome must overcome DNA damage to ensure complete chromosome replication. Here, we describe the earliest events in this process by reconstituting collisions between a eukaryotic replisome, assembled with purified proteins, and DNA damage. Lagging-strand lesions are bypassed without delay, leaving daughter-strand gaps roughly the size of an Okazaki fragment. In contrast, leading-strand polymerase stalling significantly impacts replication fork progression. We reveal that the core replisome itself can bypass leading-strand damage by re-priming synthesis beyond it. Surprisingly, this restart activity is rare, mainly due to inefficient leading-strand re-priming, rather than single-stranded DNA exposure or primer extension. We find several unanticipated mechanistic distinctions between leading- and lagging-strand priming that we propose control the replisome’s initial response to DNA damage. Notably, leading-strand restart was specifically stimulated by RPA depletion, which can occur under conditions of replication stress. Our results have implications for pathway choice at stalled forks and priming at DNA replication origins. Reconstitution of collisions between a eukaryotic replisome and DNA damage Leading-strand damage specifically causes fork stalling and uncoupling The eukaryotic replisome can re-initiate leading-strands downstream of DNA damage Multiple mechanistic differences exist between leading- and lagging-strand priming To study the earliest events following DNA polymerase stalling during replication, Taylor and Yeeles reconstituted collisions between a yeast replisome assembled with purified proteins and template DNA damage. Surprisingly, re-priming of leading-strand synthesis beyond damage is inefficient but is promoted by RPA depletion, whereas lagging-strand priming occurs robustly after damage.
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影响因子：
16
作者：
Bianchi, Julie;Rudd, Sean G.;Jozwiakowski, Stanislaw K.;Bailey, Laura J.;Soura, Violetta;Taylor, Elaine;Stevanovic, Irena;Green, Andrew J.;Stracker, Travis H.;Lindsay, Howard D.;Doherty, Aidan J.
通讯作者：
Doherty, Aidan J.
影响因子：
16.8
作者：
Sun J;Shi Y;Georgescu RE;Yuan Z;Chait BT;Li H;O'Donnell ME
通讯作者：
O'Donnell ME
影响因子：
16.6
作者：
Garbacz MA;Lujan SA;Burkholder AB;Cox PB;Wu Q;Zhou ZX;Haber JE;Kunkel TA
通讯作者：
Kunkel TA
影响因子：
4.8
作者：
McInerney, P;O'Donnell, M
通讯作者：
O'Donnell, M
影响因子：
5.6
作者：
RUPP, WD;HOWARDFL.P
通讯作者：
HOWARDFL.P