Cis-acting site on bipolar migration of the replication origin on the E.coil chromosome

大肠杆菌染色体上复制起点双极迁移的顺式作用位点

• 批准号: 14380331
• 负责人: NIKI Hironori
• 金额: $ 9.22万
• 依托单位: National Institute of Genetics
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14380331/
• 关键词: bacteria; migration; nucleoids; partitioning; segregation; 分配機構; セントロメア

During replication of the Escherichia coil chromosome, the replicated Ori domains migrate towards opposite cell poles, suggesting that a cis-acting site for bipolar migration is located in this region. To identify this cis-acting site, a series of mutants was constructed by splitting subchromosomes from the original chromosome. One mutant, containing a 720 kb subchromosome, was found to be defective in the bipolar positioning of oriC. The creation of deletion mutants allowed the identification of migS, a 25 bp sequence, as the cis-acting site for the bipolar positioning of oriC. When migS was located at the replication terminus, the chromosomal segment showed bipolar positioning. migS was able to rescue bipolar migration of plasmid DNA containing, a mutation in the SopABC partitioning system. Interestingly, multiple copies of the migS sequence on a plasmid in trans inhibited the bipolar positioning of oriC. Taken together, these findings indicate that migS plays a crucial role in the bipolar positioning of oriC. In addition, real-time analysis of the dynamic morphological changes of nucleoids in wild-type and migS mutants suggests that bipolar positioning of the replicated oriC contributes to nucleoid organization.

在复制大肠凝胶染色体时，复制的ORI结构域向相对的细胞杆迁移，这表明该区域中的双极迁移的顺式作用位点位于该区域。为了识别这个顺式作用位点，通过从原始染色体中拆分亚染色体来构建一系列突变体。发现一种含有720 kb亚染色体的突变体在oric的双极定位中有缺陷。缺失突变体的创建允许鉴定MIG，即25 bp序列，作为Oric双极定位的顺式作用位点。当MIG位于复制末端时，染色体段显示双极定位。 MIGS能够挽救含有质粒DNA的双极迁移，该质粒DNA是SOPABC分区系统中的突变。有趣的是，在反式的质粒上，MIGS序列的多个副本抑制了Oric的双极定位。综上所述，这些发现表明MIGS在Oric的双极定位中起着至关重要的作用。此外，对野生型和MIGS突变体中核苷的动态形态变化的实时分析表明，复制的OIC的双极定位有助于核苷组织。

项目成果

Yamaichi, Y., Niki, H.: "migS, a cis-acting site that affects bipolar positioning of oriC on the Escherichia coli chromosome"EMBO J. 23. 221-233 (2004)

Yamaichi, Y., Niki, H.：“migS，影响大肠杆菌染色体上 oriC 双极定位的顺式作用位点”EMBO J. 23. 221-233 (2004)

Yoshiharu Yamaichi, Hironori Niki: "migS, a cis acting site that affects bipolar migration of oriC on the Escherichia coli chromosome"The EMBO Journal. 23. 221-233 (2004)

Yoshiharu Yamaichi、Hironori Niki：“migS，一个影响大肠杆菌染色体上 oriC 双极迁移的顺式作用位点”EMBO 杂志。

Yamaichi, Y., Niki, Y.: "migS, a cis acting site that affects bipolar migratio of oriC on the Escherichia coli chromosome"The EMBO Journal.. 23. 221-233 (2004)

Yamaichi, Y., Niki, Y.：“migS，影响大肠杆菌染色体上 oriC 双极迁移的顺式作用位点”The EMBO Journal.. 23. 221-233 (2004)