DNA-PK控制了阿波罗进入领先端端粒的访问权
Ceylan Sonmez1, Beatrice Toia1, Patrik Eickhoff2
1Department of Biomedical and Clinical Sciences, Linköping University, Linköping 58 183, Sweden.
Nucleic acids research
|February 26, 2024
概括
DNA-PK通过与核酶阿波罗结合来调节前端端粒切除. 这种相互作用依赖于DNA-PKcs激酶活性和酸化,将阿波罗定位在DNA末端,防止端粒融合.
科学领域:
- 分子生物学分子生物学
- DNA 修复机制的修复机制
- 端粒生物学 端粒生物学
背景情况:
- Ku70/80和DNA-PKcs (DNA-PK) 复合体对于通过正规非同源端连接 (c-NHEJ) 进行DNA双链断裂修复至关重要.
- DNA-PK还在防止新复制的前端端粒的融合方面发挥了矛盾的作用.
研究的目的:
- 阐明DNA-PK在调节Apollo/DCLRE1B/SNM1B,即负责切除前端端粒的核酶中的作用.
- 为了研究DNA-PK对阿波罗的端粒功能控制的分子机制.
主要方法:
- 生物化学测试以评估DNA-PK与阿波罗的相互作用.
- 用AlphaFold-Multimer进行阿波罗-DNA-PKcs复合物的结构预测.
- 对DNA-PKcs激酶活性和酸化位点的分析 (ABCDE/Thr2609集群).
主要成果:
- 阿波罗的端粒功能需要DNA-PKcs激酶活性和直接与DNA-PK结合.
- 结构预测表明,阿波罗的核酶域和DNA-PKcs之间存在广泛的相互作用.
- DNA-PK的端粒功能依赖于ABCDE/Thr2609酸化集群,类似于阿尔特米斯调节.
结论:
- DNA-PK通过与阿波罗结合,并通过酸化促进其在DNA末端的定位来调节前端端粒切除.
- 这种机制类似于,但与DNA-PK在V(D) J重组过程中对Artemis的调节不同.
- 这些发现揭示了DNA-PK在维持端粒完整性方面的新角色.
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