Human checkpoint kinase ataxia telangiectasia-mutated (ATM) plays a key role in initiation of the DNA damage response following DNA double-strand breaks. ATM inhibition is a promising approach in cancer therapy, but, so far, detailed insights into the binding modes of known ATM inhibitors have been hampered due to the lack of high-resolution ATM structures. Using cryo-EM, we have determined the structure of human ATM to an overall resolution sufficient to build a near-complete atomic model and identify two hitherto unknown zinc-binding motifs. We determined the structure of the kinase domain bound to ATPγS and to the ATM inhibitors KU-55933 and M4076 at 2.8 Å, 2.8 Å and 3.0 Å resolution, respectively. The mode of action and selectivity of the ATM inhibitors can be explained by structural comparison and provide a framework for structure-based drug design.

人类检查点激酶共济失调毛细血管扩张症突变 (ATM) 在 DNA 双链断裂后启动 DNA 损伤反应中起着关键作用。ATM 抑制是一种很有前途的癌症治疗方法，但到目前为止，由于缺乏高分辨率的 ATM 结构，对已知 ATM 抑制剂结合模式的详细了解受到阻碍。使用低温 EM，我们已经确定了人类 ATM 的结构，其整体分辨率足以构建一个近乎完整的原子模型，并识别出两个迄今为止未知的锌结合基序。我们分别以 2.8 Å、2.8 Å 和 3.0 Å 分辨率确定了与 ATPγS 和 ATM 抑制剂 KU-55933 和 M4076 结合的激酶结构域的结构。