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TIRR通过掩盖其氨酸甲基氨酸结合功能来调节53BP1
Pascal Drané1, Marie-Eve Brault1, Gaofeng Cui2
1Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115, USA.
Nature
|February 28, 2017
概括
图多互动修复调节器 (TIRR) 掩盖了DNA修复蛋白53BP1
科学领域:
- DNA 修复机制
- 表观遗传学
- 细胞信号传输
背景情况:
- 在DNA双链断裂修复和癌症治疗中,P53结合蛋白1 (53BP1) 是至关重要的.
- 53BP1的功能依赖于其对H4K20me2的Tudor域结合.
- 了解53BP1的调节是针对癌症治疗的关键.
研究的目的:
- 在DNA修复中确定53BP1功能的新调节剂.
- 阐明TIRR影响53BP1活动的机制.
- 研究TIRR在DNA损伤反应途径中的作用.
主要方法:
- 蛋白相互作用研究以描述TIRR和53BP1的结合.
- 在DNA损伤时进行细胞测试以评估53BP1的定位和功能.
- 基因操纵 (过度表达和耗尽) 来研究TIRR对DNA修复的影响.
主要成果:
- 图多互动修复调节器 (TIRR) 直接结合53BP1的图多域,掩盖H4K20me2的结合.
- 53BP1和RIF1的ATM介导化会在DNA受损时破坏53BP1-TIRR复合体.
- 过度表达TIRR抑制了53BP1的双链断裂,而TIRR的耗尽则破坏了53BP1的稳定.
结论:
- 通过掩盖其基因组结合部位,TIRR作为53BP1的新兴抑制剂.
- 在DNA修复过程中通过ATM信号动态调节53BP1-TIRR相互作用.
- TIRR代表了调节癌症DNA修复的新治疗标.
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