Study of the G1-phase specific novel repair pathway for X-ray-induced DNA damage

X射线诱导的DNA损伤G1期特异性新型修复途径的研究

• 批准号: 18510050
• 负责人: IWABUCHI Kuniyoshi
• 金额: $ 2.61万
• 依托单位: Kanazawa Medical University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18510050/
• 关键词: Molecular biology; nuculeus; DNA double-strand break; Ionizing radiation; repair; Nonhomologous end joining; 53BP1; DNA損傷

Ionizing radiation (IR) induces a variety of DNA lesions. The most significant lesion is a DNA double-strand break (DSB), which is repaired by homologous recombination or nonhomologous end joining (NHEJ) pathway. Since we previously demonstrated that IR-responsive protein 53BP1 specifically enhances activity of DNA ligase IV, a DNA ligase required for NHEJ, we investigated responses of 53BP1-deficient chicken DT40 cells to IR. 53BP1-deficient cells showed increased sensitivity to X-rays during G1 phase. Although intra-S and G2/M checkpoints were intact, a frequency of isochromatid-type chromosomal aberrations was elevated after irradiation in 53BP1-deficient cells. Furthermore, disappearance of X-ray-induced γ-H2AX foci, a marker of DNA DSBs, was prolonged in 53BP1-deficient cells. Thus, the elevated X-ray sensitivity in G1 phase cells was attributable to repair defect for IR-induced DNA-damage. Epistasis analysis revealed that 53BP1 plays a role in a pathway distinct from the Ku-dependent and Artemis-dependent NHEJ pathways, but requires DNA ligase IV. Strikingly, disruption of the 53BP1 gene together with inhibition of phosphatidylinositol 3-kinase family by wortmannin completely abolished colony formation by cells irradiated during G1 phase. These results demonstrate that the 53BP1-dependent repair pathway is important for survival of cells irradiated with IR during the G1 phase of the cell cycle.

电离辐射 (IR) 会诱发多种 DNA 损伤，其中最重要的损伤是 DNA 双链断裂 (DSB)，该损伤可通过同源重组或非同源末端连接 (NHEJ) 途径进行修复。蛋白质 53BP1 特异性增强 DNA 连接酶 IV（NHEJ 所需的 DNA 连接酶）的活性，我们研究了 53BP1 缺陷鸡 DT40 细胞对 DNA 连接酶 IV 的反应。 IR。53BP1 缺陷细胞在 G1 期表现出对 X 射线的敏感性增加，尽管 S 内和 G2/M 检查点完整，但 53BP1 缺陷细胞中等染色单体型染色体畸变的频率升高。此外，消失。 X 射线诱导的 γ-H2AX 焦点（DNA DSB 的标记）在 53BP1 缺陷细胞中延长。 G1 期细胞中 X 射线敏感性的升高归因于 IR 诱导的 DNA 损伤的修复缺陷，上位性分析表明 53BP1 在不同于 Ku 依赖性和 Artemis 依赖性 NHEJ 途径的途径中发挥作用，但需要 DNA。引人注目的是，53BP1 基因的破坏以及渥曼青霉素对磷脂酰肌醇 3-激酶家族的抑制完全消除了细胞的集落形成。这些结果表明，53BP1 依赖性修复途径对于细胞周期 G1 期接受 IR 照射的细胞的存活很重要。

项目成果

BRCT domain protein PTIP disruptants of chicken DT40 cells are viable, butdefective in proliferation and highly sensitive to ionizing radiation.

鸡DT40细胞的BRCT结构域蛋白PTIP破坏体是可行的，但增殖有缺陷并且对电离辐射高度敏感。

• 发表时间: 2007
• 作者: Nakamura;K.;Sakamoto;S.;Iijima;K.;Mochizuki;D.;Teshigawara;K. Kobavashi;J.;Matsuura;S.;Tauchi;H.;Komatsu;K;Kobayashi J;Kobayashi J;Matsumoto M;Matsumoto M;Matsumoto M;Iwabuchi K;Iwabuchi K;Iwabuchi K;岩淵 邦芳;Iwabuchi K;岩淵 邦芳;Iwabuchi K;Iwabuchi K;Iwabuchi K;Morohoshi F;Utsumi H;Morohoshi F;Utsumi H;Morohoshi F
• 通讯作者: Morohoshi F

53BP1-dependent repair pathway for X-ray induced DNA damage.

X 射线诱导的 DNA 损伤的 53BP1 依赖性修复途径。

• 发表时间: 2007
• 作者: Nakamura;K.;Sakamoto;S.;Iijima;K.;Mochizuki;D.;Teshigawara;K. Kobavashi;J.;Matsuura;S.;Tauchi;H.;Komatsu;K;Kobayashi J;Kobayashi J;Matsumoto M;Matsumoto M;Matsumoto M;Iwabuchi K;Iwabuchi K;Iwabuchi K;岩淵 邦芳;Iwabuchi K;岩淵 邦芳;Iwabuchi K
• 通讯作者: Iwabuchi K

Suppression of DNA-damage dependent total premature separation by 53BP1

53BP1 抑制 DNA 损伤依赖性完全过早分离

• 发表时间: 2006
• 作者: Nakamura;K.;Sakamoto;S.;Iijima;K.;Mochizuki;D.;Teshigawara;K. Kobavashi;J.;Matsuura;S.;Tauchi;H.;Komatsu;K;Kobayashi J;Kobayashi J;Matsumoto M;Matsumoto M;Matsumoto M;Iwabuchi K;Iwabuchi K;Iwabuchi K;岩淵 邦芳;Iwabuchi K;岩淵 邦芳;Iwabuchi K;Iwabuchi K;Iwabuchi K;Morohoshi F;Utsumi H;Morohoshi F;Utsumi H;Morohoshi F;Iwabuchi K;Iwabuchi K;岩淵 邦芳;Iwabuchi K
• 通讯作者: Iwabuchi K

Use of a cell sorter for fractionation of G1 phase DT40 cells

使用细胞分选仪分离 G1 期 DT40 细胞

• 发表时间: 2007
• 作者: Nakamura;K.;Sakamoto;S.;Iijima;K.;Mochizuki;D.;Teshigawara;K. Kobavashi;J.;Matsuura;S.;Tauchi;H.;Komatsu;K;Kobayashi J;Kobayashi J;Matsumoto M;Matsumoto M;Matsumoto M;Iwabuchi K;Iwabuchi K;Iwabuchi K;岩淵 邦芳;Iwabuchi K;岩淵 邦芳;Iwabuchi K;Iwabuchi K
• 通讯作者: Iwabuchi K

Current topics in DNA double-strand break repair

• DOI: 10.1269/jrr.07130
• 发表时间: 2008-03-01
• 期刊: JOURNAL OF RADIATION RESEARCH
• 影响因子: 2
• 作者: Kobayashi, Junya;Iwabuchi, Kuniyoshi;Tauchi, Hiroshi
• 通讯作者: Tauchi, Hiroshi