DNA stretching by bacterial initiators promotes replication origin opening.
DNA stretching by bacterial initiators promotes replication origin opening.
复制标题
通过细菌启动器拉伸的DNA促进了复制起源。
DOI：
10.1038/nature10455
复制
发表时间：
2011-10-02
期刊：
影响因子：
64.8
通讯作者：
Berger, James M.
中科院分区：
文献类型：
--
作者：
Duderstadt, Karl E.;Chuang, Kevin;Berger, James M.
许多复制起始物形成高阶寡聚体，其加工宿主起点以促进复制体形成。除了专用的双链体DNA结合结构域之外，细胞引发剂还具有AAA+（与各种细胞活性相关的ATP酶）元件，其驱动从蛋白质组装到起源识别的功能。在细菌中，引发剂DnaA的AAA+结构域已被认为结合在起始解链期间形成的单链DNA。在这里，我们显示晶体学和解决方案，ATP依赖的组装DnaA成螺旋低聚物创建一个连续的表面，允许连续的AAA+域绑定和扩展单链DNA片段。结合的机制出乎意料地类似于RecA（同源重组因子）的结合机制，但其不同之处在于DnaA促进阻止互补链配对的核酸构象。这些发现，结合链置换试验，表明DnaA熔化复制起点的直接ATP依赖性拉伸机制。比较研究揭示了DnaA用于接合DNA底物和其他核酸依赖性AAA+系统的方法之间的显着共性。
Many replication initiators form higher-order oligomers that process host origins to promote replisome formation. In addition to dedicated duplex DNA-binding domains, cellular initiators possess AAA+ (ATPases Associated with various cellular Activities) elements that drive functions ranging from protein assembly to origin recognition. In bacteria, the AAA+ domain of the initiator DnaA has been suggested to bind single-stranded DNA formed during origin melting. Here we show crystallographically and in solution that the ATP-dependent assembly of DnaA into a spiral oligomer creates a continuous surface that allows successive AAA+ domains to bind and extend single-stranded DNA segments. The mechanism of binding is unexpectedly similar to that of RecA, a homologous recombination factor, but it differs in that DnaA promotes a nucleic acid conformation that prevents pairing of a complementary strand. These findings, combined with strand-displacement assays, indicate that DnaA melts replication origins by a direct ATP-dependent stretching mechanism. Comparative studies reveal remarkable commonalities between the approach used by DnaA to engage DNA substrates and other, nucleic acid-dependent AAA+ systems.
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影响因子：
16.8
作者：
Conway, AB;Lynch, TW;Rice, PA
通讯作者：
Rice, PA
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
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通讯作者：
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影响因子：
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作者：
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通讯作者：
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影响因子：
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作者：
Crisona, Nancy J.;Cozzarelli, Nicholas R.
通讯作者：
Cozzarelli, Nicholas R.
影响因子：
56.9
作者：
Dueber, Erin L. Cunningham;Corn, Jacob E.;Berger, James M.
通讯作者：
Berger, James M.