Ku蛋白是一种DNA双链断裂修复结合蛋白,可以与多种DNA末端相结合。Ku蛋白由于其对DNA末端的识别保护作用和对整个非同源末端连接修复复合体的成核作用而成为NHEJ有效性的主要决定因素,决定着细胞的损伤修复能力。此外在包括端粒区的维持、抗凋亡、肿瘤抑制以及基因转录的调控等方面都发挥着重要作用。抑制肿瘤细胞中Ku蛋白的表达,可以有效减少其放疗后DNA双链断裂的修复,从而达到提高其放射敏感性的目的。 Ku protein is a DNA double-strand break repair binding protein that binds to multiple DNA ends. Ku protein is the major determinant of NHEJ availability due to its recognition and protection of the DNA termini and nucleation of the entire non-homologous end joining repair complex, which determines the ability of the cell to repair damage. In addition, including the maintenance of telomere region, anti-apoptosis, tumor suppression and regulation of gene transcription plays an important role. Inhibition of the expression of Ku protein in tumor cells can effectively reduce the DNA double-strand breaks after radiotherapy, so as to improve its radiosensitivity.