Structure and inhibitor specificity of the PCTAIRE-family kinase CDK16.
Structure and inhibitor specificity of the PCTAIRE-family kinase CDK16.
复制标题
DOI：
10.1042/bcj20160941
复制
发表时间：
2017-02-20
期刊：
影响因子：
--
通讯作者：
Bullock AN
中科院分区：
文献类型：
--
作者：
Dixon-Clarke SE;Shehata SN;Krojer T;Sharpe TD;von Delft F;Sakamoto K;Bullock AN
CDK 16（也称为PCTAIRE 1或PCTK 1）是细胞周期蛋白依赖性激酶（CDK）家族的非典型成员，已成为神经突生长，囊泡运输和癌细胞增殖的关键调节因子。CDK 16通过磷酸化依赖性14-3-3相互作用与细胞周期蛋白Y结合而被激活，并且与常规CDK相比具有独特的共有底物磷酸化基序。为了阐明这种非典型CDK的结构和底物结合特性，我们针对不同的抑制剂文库筛选了CDK 16激酶结构域，并确定了鉴定命中的共结构。我们发现CDK 16的ATP结合口袋可以容纳I型和II型激酶抑制剂。通过无细胞和基于细胞的测定揭示的最有效的CDK 16抑制剂是多靶向癌症药物dabrafenib和rebastinib。通过分别与抑制剂靛玉红E804和rebastinib的单独复合物中CDK 16的第一晶体结构证实了无活性DFG-外结合构象。结构显示了相当大的构象可塑性，这表明在没有细胞周期蛋白伴侣的情况下，分离的CDK 16激酶结构域相对不稳定。这里确定的不寻常的结构特征和化学支架为开发更具选择性的CDK 16抑制剂提供了希望，并为更好地研究CDK 16及其相关CDK家族成员在各种生理和病理环境中的作用提供了机会。
CDK16 (also known as PCTAIRE1 or PCTK1) is an atypical member of the cyclin-dependent kinase (CDK) family that has emerged as a key regulator of neurite outgrowth, vesicle trafficking and cancer cell proliferation. CDK16 is activated through binding to cyclin Y via a phosphorylation-dependent 14-3-3 interaction and has a unique consensus substrate phosphorylation motif compared with conventional CDKs. To elucidate the structure and inhibitor-binding properties of this atypical CDK, we screened the CDK16 kinase domain against different inhibitor libraries and determined the co-structures of identified hits. We discovered that the ATP-binding pocket of CDK16 can accommodate both type I and type II kinase inhibitors. The most potent CDK16 inhibitors revealed by cell-free and cell-based assays were the multitargeted cancer drugs dabrafenib and rebastinib. An inactive DFG-out binding conformation was confirmed by the first crystal structures of CDK16 in separate complexes with the inhibitors indirubin E804 and rebastinib, respectively. The structures revealed considerable conformational plasticity, suggesting that the isolated CDK16 kinase domain was relatively unstable in the absence of a cyclin partner. The unusual structural features and chemical scaffolds identified here hold promise for the development of more selective CDK16 inhibitors and provide opportunity to better characterise the role of CDK16 and its related CDK family members in various physiological and pathological contexts.