二本鎖ＤＮＡ切断により誘導される複製プログラム変動のメカニズム

双链DNA断裂诱导复制程序变异的机制

• 批准号: 14F03511
• 负责人: 正井 久雄
• 金额: $ 1.54万
• 依托单位: Tokyo Metropolitan Institute of Medical Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2014
• 资助国家: 日本
• 起止时间: 2014-04-25 至 2017-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14F03511/
• 关键词: Rif1; yKu70; Double-strand DNA break; DNA replication; Replication origin; Late and dormant origin; Telomere; Budding yeast; Double-strand break; Dormant origins

Various types of DNA damage can induce activation of dormant replication origins. Previous studies showed that a single and irrepairable double-strand break (DSB) in the proximity of a dormant replication origin is able to promote origin firing, likely to rescue replication of the broken chromosome fragment (Doksani et al., Cell 2009). In this study, We aim at elucidating the mechanisms leading to dormant origin firing following DSB formation.Here we showed that DNA damage checkpoints do not counteract DSB-induced dormant origin firing but the dormant origin firing activities are counteracted by histone acetylation state. We also identified telomere-related proteins, Rif1 and Ku complex, as potential regulators of dormant origins even in the absence of DSB. We found that Rif1 and yKu70 bind preferentially at regions between dormant origins and DSB site but not at the other side of the DSB site. The binding profiles of Rif1 and yKu70 at those regions are not affected by DSB formation. Besides, we found that absence of yKu70 prevents Rif1 from binding at regions between dormant origins and DSB site. Our results indicate an important role of Rif1 and yKu70 in controlling dormant origin activity near to DSB site.

各种类型的DNA损伤可以诱导休眠复制起源的激活。先前的研究表明，在休眠复制起源附近，单个和不可拨的双链断裂（DSB）能够促进起源射击，这可能会挽救破裂的染色体片段的复制（Doksani等人，Cell 2009）。在这项研究中，我们旨在阐明导致DSB形成后休眠起源的机制。在这里，我们表明DNA损伤检查点不会抵消DSB诱导的休眠起源射击，但休眠起源发射活动被组蛋白乙酰化状态抵消。我们还确定了与端粒相关的蛋白RIF1和KU复合物，即使在没有DSB的情况下，也是休眠起源的潜在调节剂。我们发现RIF1和YKU70优先在休眠起源和DSB位点之间的区域结合，而在DSB位点的另一侧则没有结合。这些区域RIF1和YKU70的结合曲线不受DSB形成的影响。此外，我们发现不存在YKU70可防止RIF1在休眠起源和DSB位点之间的区域结合。我们的结果表明，RIF1和YKU70在控制DSB站点附近的休眠起源活动中的重要作用。

项目成果

“DNA replication: From Old Principles to New Discovery” in “Advances in Experimental Medicine and Biology”

《实验医学与生物学进展》中的“DNA复制：从旧原理到新发现”

• 发表时间: 2017
• 作者: Kenji Moriyama;Mong Sing Lai;and Hisao Masai
• 通讯作者: and Hisao Masai

Mrc1/Claspinの分子内相互作用による活性制御および新規機能

Mrc1/Claspin通过分子内相互作用的活性控制和新功能

• 发表时间: 2014
• 作者: 3.Ushijima H;Nishimura S;Thongprachum A;Shimizu-Onda Y;Tran DN;Pham NT;Takanashi S;Dey SK;Okitsu S;Yamazaki W;Mizuguchi M;Hayakawa S.;Hisao Masai;G. Greaves;正井 久雄
• 通讯作者: 正井 久雄

Regulation of DNA replication program in fission yeast and human cells

裂殖酵母和人类细胞中 DNA 复制程序的调控

• 发表时间: 2014
• 作者: 3.Ushijima H;Nishimura S;Thongprachum A;Shimizu-Onda Y;Tran DN;Pham NT;Takanashi S;Dey SK;Okitsu S;Yamazaki W;Mizuguchi M;Hayakawa S.;Hisao Masai
• 通讯作者: Hisao Masai

公益財団法人東京都医学総合研究所ゲノム動態プロジェクト

东京都医学科学研究所基因组动力学项目

ATM in prevention of genomic instability.

• DOI: 10.4161/cc.28216
• 发表时间: 2014
• 期刊: Cell cycle (Georgetown, Tex.)
• 作者: Masai H