Molecular determinants of origin discrimination by Orc1 initiators in archaea.
Molecular determinants of origin discrimination by Orc1 initiators in archaea.
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DOI：
10.1093/nar/gkq1308
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发表时间：
2011-05
影响因子：
14.9
通讯作者：
Berger JM
中科院分区：
文献类型：
--
作者：
Dueber EC;Costa A;Corn JE;Bell SD;Berger JM
与细菌不同，许多真核生物从缺乏明显序列保守性的基因组位点启动 DNA 复制。这些基因座由起源识别复合物 (ORC) 识别和结合，随后被一系列事件激活，其中包括招募附加因子 Cdc6。古细菌通常拥有一种或多种 Orc1/Cdc6 同源物，属于与各种细胞活动相关的 ATP 酶起始分支 (AAA+) 超家族；然而，这些蛋白质识别复制起点内的特定序列。原子分辨率研究表明，古细菌 Orc1 蛋白通过 N 端 AAA+ 结构域和 C 端翼状螺旋结构域 (WHD) 接触双链 DNA，但使用的碱基特异性接触非常少。为了研究这些关联的生化效应，我们突变了来自古细菌硫磺叶菌的 Orc1-1 和 Orc1-3 旁系同源物的 DNA 相互作用元件，并测试了它们对起源结合和变形的影响。我们发现 AAA+ 结构域在控制 DNA 结合的序列选择性方面具有意想不到的作用，尽管该区域不存在碱基特异性接触。我们的结果表明，WHD 和 ATPase 区域都会影响 Orc1/Cdc6 的起源识别，并表明不仅 DNA 序列，而且局部 DNA 结构都有助于定义古菌起始子结合位点。
Unlike bacteria, many eukaryotes initiate DNA replication from genomic sites that lack apparent sequence conservation. These loci are identified and bound by the origin recognition complex (ORC), and subsequently activated by a cascade of events that includes recruitment of an additional factor, Cdc6. Archaeal organisms generally possess one or more Orc1/Cdc6 homologs, belonging to the Initiator clade of ATPases associated with various cellular activities (AAA+) superfamily; however, these proteins recognize specific sequences within replication origins. Atomic resolution studies have shown that archaeal Orc1 proteins contact double-stranded DNA through an N-terminal AAA+ domain and a C-terminal winged-helix domain (WHD), but use remarkably few base-specific contacts. To investigate the biochemical effects of these associations, we mutated the DNA-interacting elements of the Orc1-1 and Orc1-3 paralogs from the archaeon Sulfolobus solfataricus, and tested their effect on origin binding and deformation. We find that the AAA+ domain has an unpredicted role in controlling the sequence selectivity of DNA binding, despite an absence of base-specific contacts to this region. Our results show that both the WHD and ATPase region influence origin recognition by Orc1/Cdc6, and suggest that not only DNA sequence, but also local DNA structure help define archaeal initiator binding sites.
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影响因子：
10.5
作者：
Eaton, Matthew L.;Galani, Kyriaki;MacAlpine, David M.
通讯作者：
MacAlpine, David M.
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.
影响因子：
4.6
作者：
King, JY;Ferrara, R;Ashley, EA
通讯作者：
Ashley, EA
影响因子：
11.4
作者：
Remus, D;Beall, EL;Botchan, MR
通讯作者：
Botchan, MR
DOI：
10.1073/pnas.0400340101
发表时间：
2004-03-02
影响因子：
11.1
作者：
McGarry, KC;Ryan, VT;Leonard, AC
通讯作者：
Leonard, AC