p53 dependent S checkpoint in early mouse embryos and radiation induction of genomic instability

早期小鼠胚胎中p53依赖性S检查点和基因组不稳定性的辐射诱导

基本信息

批准号：
14208067
负责人：
NIWA Ohtsura
金额：
$ 13.73万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14208067/
关键词：
p53 dependent S checkpoint suppression of replication fork progression transactivation independent DNA binding domain ATM dependency sperm irradiated zygotes pink eyed unstable allele reversion mutation ゲノム防御機構マウス初期胚遅延アポトーシス遅延細胞周期

项目摘要

Elevated levels of mutations were found at the maternally derived alleles of the Ms6hm minisatellite locus and the pink-eyed unstable locus in F1 mice born to male mice irradiated at the spermatozoa stage. These mutations demonstrated the operation of untargeted and delayed recombinational mutations due to genomic instability which was induced during early mouse development by radiation DNA damage introduced by the irradiated sperm. In order to elucidate the molecular mechanism of genomic instability, we have undertaken studies of damage response in sperm irradiated mouse embryos.A p53 responsible reporter plasmid microinjected into zygotes was transcriptionally activated when they zygotes were fertilized with irradiated sperm. This pronuclear cross-talk was found to suppress DNA synthesis of female pronucleus as well as of male pronucleus in sperm irradiated zygotes. This suppression of DNA synthesis was not observed in p53-/-zygotes which was restored when the sperm irradiated p53-/-zygotes were microinjected with p53 protein, suggesting a novel pathway of S checkpoints. Microinjection of mutant p53 proteins into sperm irradiated p53-/-zygotes demonstrated that this p53 dependent S checkpoint required DNA binding domain of p53,but the transactivation domain.The p53 dependent S checkpoint was analyzed in primary mouse and found operate at doses below 2 Gy. In addition, analyses of DNA fiber elongation by double labeling the cells with Id U and Cld U showedthatthe p53 dependent S checkpoint suppressed DNA synthesis by slowing down of replication fork progression. This slowing down of replication was associated with a higher rate of recombination between sister chromatids which can explain the untargeted recombination of minisatellite. Delayed recombination observed at the pink-eyed unstable allele requires yet another mechanism of damage memory for which much more to be studied yet.

在MS6HM Minisatellite基因座的母体衍生的等位基因和粉红色眼睛的不稳定基因座的F1小鼠中，在精子阶段辐照的雄性小鼠出生的F1小鼠中发现了突变水平升高。这些突变表明，由于基因组不稳定性引起的非靶向和延迟重组突变的运行，这在小鼠早期发育过程中通过辐射的精子引入的辐射DNA损伤引起。为了阐明基因组不稳定性的分子机制，我们对精子受辐照的小鼠胚胎的损伤反应进行了研究。Ap53负责任的报告基因质粒显微注射到Zygotes中时，当它们用辐照精子施肥时，被转录激活。发现这种前核串扰可抑制精子辐照的合子中雌性原核以及雄性原核的DNA合成。在p53 - / - 合子中未观察到这种DNA合成的抑制作用，当精子辐照的p53 - / - zygotes与p53蛋白微注射时，该合子恢复了，这表明S检查点的新途径。将突变体p53蛋白的显微注射到精子辐照的p53 - / - zygotes中表明，该p53依赖性S检查点需要p53的DNA结合结构域，但是p53依赖性S检查点在主小鼠中分析并在剂量下进行分析，并在低于剂量的剂量下进行操作。此外，通过双重标记具有ID U和CLD U的细胞来显示p53依赖的S检查点通过双重标记DNA纤维伸长的分析，从而抑制了DNA合成，从而减慢了复制叉进程的减慢。这种复制的放缓与姐妹染色单体之间的重组率更高有关，这可以解释微型卫星的未固定重组。在粉红色的不稳定等位基因上观察到的延迟重组需要另一种损害记忆的机制，还需要研究更多。

项目成果

期刊论文数量（17）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Predisposition to mouse thymic lymphomas in response to ionizing radiation depends on variant alleles encoding metal-responsive transcription factor-1 (Mtf-1).

电离辐射对小鼠胸腺淋巴瘤的易感性取决于编码金属反应转录因子 1 (Mtf-1) 的变异等位基因。

DOI：
发表时间：
2005
期刊：
Oncogene 24
影响因子：
0
作者：
Hashimoto;T.;Yamaoka;K.;Sakai;Y.;A.OOTSUYAMA;Y.Tamura
通讯作者：
Y.Tamura

Generation of multipotent stem cells from postnatal mouse testis.

从出生后小鼠睾丸中产生多能干细胞。

DOI：
发表时间：
2004
期刊：
Cell 119
影响因子：
0
作者：
Kanatsu-Shinohara M.;Inoue K.;Lee J.;Yoshimoto M.;Ogonuki N.;Miki H.;Baba T.;Kazuki Y.;Toyokuni S.;Oshimura M.;Heike T.;Nakahata T.;Ishino F.;Ogura A.;Shinohara T
通讯作者：
Shinohara T

RERF : the monument and the crisis

RERF：纪念碑与危机

DOI：
发表时间：
2004
期刊：
Radiat.Res. 162
影响因子：
0
作者：
Toyoshima M et al.;Kubota T et al.;Umesako S et al.;Tamura Y et al.;Kanatsu-Shinohara M et al.;Niwa O
通讯作者：
Niwa O

丹羽太貫: "Induced genomic instability in irradiated germ cells and in the offspring ; reconciling discrepancies among the human and animal studies."Oncogene. 22. 7078-7086 (2003)

Taiki Niwa：“在受辐射的生殖细胞和后代中诱导基因组不稳定；协调人类和动物研究之间的差异。”Oncogene。22. 7078-7086 (2003)