This review focuses on DNA–dependent protein kinase (DNA–PK), which is the key regulator of canonical non–homologous end–joining (NHEJ), the predominant mechanism of DNA double–strand break (DSB) repair in mammals. DNA–PK consists of the DNA–binding Ku70/80 heterodimer and the catalytic subunit DNA–PKcs. They assemble at DNA ends, forming the active DNA–PK complex, which initiates NHEJ–mediated DSB repair. Paradoxically, both Ku and DNA–PKcs are associated with telomeres, and they play crucial roles in protecting the telomere against fusions. Herein, we discuss possible mechanisms and contributions of Ku and DNA–PKcs in telomere regulation.

中文翻译：

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DNA依赖性蛋白激酶在端粒的维护和保护中。

这篇综述集中在依赖DNA的蛋白激酶（DNA-PK），这是规范的非同源末端连接（NHEJ）的关键调节剂，NHEJ是哺乳动物DNA双链断裂（DSB）修复的主要机制。DNA-PK由结合DNA的Ku70 / 80异二聚体和催化亚基DNA-PKcs组成。它们在DNA末端组装，形成活性DNA-PK复合物，从而启动NHEJ介导的DSB修复。矛盾的是，Ku和DNA-PKcs都与端粒有关，它们在保护端粒免于融合中起着至关重要的作用。在本文中，我们讨论了Ku和DNA-PKcs在端粒调控中的可能机制和贡献。